718 results on '"M. Yen"'
Search Results
2. Reply to: 'Hyperhomocysteinemia predicts liver-related clinical outcomes in the general population'
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Madhulika Tripathi, Brijesh Kumar Singh, and Paul M. Yen
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Hepatology - Published
- 2023
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3. Review of Modern Insulin Pumps and the Perioperative Management of the Type 1 Diabetic Patient for Ambulatory Dental Surgery
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Andrew S. Young and Philip M Yen
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Blood Glucose ,Insulin pump ,medicine.medical_specialty ,medicine.medical_treatment ,Sedation ,Ambulatory Care Facilities ,Insulin Infusion Systems ,medicine ,Humans ,Hypoglycemic Agents ,Insulin ,Intensive care medicine ,Glycemic ,Type 1 diabetes ,Perioperative management ,business.industry ,medicine.disease ,Diabetes Mellitus, Type 1 ,Anesthesiology and Pain Medicine ,Continuing Education in Memory of Norman Trieger, Dmd, Md ,Ambulatory Surgical Procedures ,Dental surgery ,Ambulatory ,medicine.symptom ,business - Abstract
The use of continuous insulin pump systems for effective management of glycemic control in the patient with type 1 diabetes mellitus (T1DM) is steadily increasing. Although the types of devices and their respective manufacturers vary, insulin pumps all utilize similar underlying concepts based on the delivery of exogenous insulin to patients with T1DM in manners that more closely approximate the normal biologic function and performance of the pancreas. As insulin pumps becomes more commonplace and their use more widespread, the sedation or anesthesia provider must ensure familiarity with the basic knowledge of pump function and the various perioperative management considerations. This review provides a concise overview of the pathophysiology of T1DM, introduces foundational aspects of common insulin pump systems, and discusses several general recommendations regarding the perioperative management of insulin pumps during dental surgeries.
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- 2021
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4. Metabolomics to assess thyroid hormone status?
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Heleen I Jansen, Eveline Bruinstroop, Paul M Yen, Laboratory for Endocrinology, Endocrinology, and Amsterdam Gastroenterology Endocrinology Metabolism
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Endocrinology ,Endocrinology, Diabetes and Metabolism ,levothyroxine ,Biochemistry (medical) ,Clinical Biochemistry ,hypothyroidism ,metabolomics ,personalized treatment ,Biochemistry - Published
- 2022
5. Outcomes 12 Months After Temperature-Controlled Radiofrequency Device Treatment of the Nasal Valve for Patients With Nasal Airway Obstruction
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Joseph K. Han, Stacey L. Silvers, Jon N. Rosenthal, Chad M. McDuffie, and David M. Yen
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Male ,Treatment Outcome ,Otorhinolaryngology ,Quality of Life ,Temperature ,Humans ,Surgery ,Female ,Prospective Studies ,Middle Aged ,Nasal Obstruction - Abstract
ImportanceNasal valve collapse is a primary cause of nasal airway obstruction (NAO). Patients with NAO and nasal valve collapse experience a variety of symptoms that lower their quality of life, such as nasal congestion, headache, sleep disturbance, daytime sleepiness, and snoring.ObjectiveTo determine if active treatment of the nasal valve with a temperature-controlled radiofrequency (TCRF) device, previously demonstrated superior to a sham procedure at 3 months, was safe and associated with sustained improvements in symptoms of NAO through 12 months.Design, Setting, and ParticipantsIn a prospective, multicenter, single-blinded, randomized clinical trial, patients in 16 centers in the US with index procedures between August and December 2020 were assigned to TCRF device treatment of the nasal valve or a sham control procedure (no RF energy). Patients had a baseline Nasal Obstruction Symptom Evaluation (NOSE) Scale score of 55 or greater with nasal valve collapse as the primary or substantial contributor to NAO. After primary end point evaluation at 3 months, eligible patients in the sham control arm crossed over to active treatment. Data analysis was performed between April and May 2022.InterventionsPatients were treated bilaterally with the TCRF device at 4 or fewer nonoverlapping areas on the nasal mucosa at the junction of the upper and lower lateral cartilage on the lateral nasal wall.Main Outcomes and MeasuresThe primary end point measure was responder rate, defined as 20% or greater reduction in NOSE Scale score or 1 or greater reduction in NOSE Scale clinical severity category.ResultsA total of 108 patients received active treatment (77 as index active treatment, 31 after crossover). The mean (SD) age of patients was 48.5 (12.3) years; 66 (61.1%) were women. The combined group of patients receiving active treatment had a mean baseline NOSE Scale score of 76.3 (95% CI, 73.6-79.1). At 12 months (n = 88), the responder rate was 89.8% (95% CI, 81.7%-94.5%). The NOSE Scale score improved from baseline (mean change, −44.9 [95% CI, −52.1 to −37.7]). No device/procedure-related serious adverse events were reported.Conclusions and RelevanceIn this follow-up of a cohort from a randomized clinical trial, the minimally invasive TCRF device, previously demonstrated to be superior to a sham procedure, was safe and associated with improvement in symptoms of NAO through 12 months postprocedure.Trial RegistrationClinicalTrials.gov Identifier: NCT04549545
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- 2022
6. Cryosurgical Ablation for Treatment of Rhinitis: Two‐Year Results of a Prospective Multicenter Study
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Ellen M O'Malley, Kent Lam, Joseph K. Han, Randall A. Ow, and David M Yen
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Adult ,Male ,medicine.medical_specialty ,medicine.medical_treatment ,Cryotherapy ,Cryosurgery ,Allergic rhinitis ,03 medical and health sciences ,0302 clinical medicine ,Nonallergic rhinitis ,Quality of life ,Allergy, Rhinology, and Immunology ,Internal medicine ,Surveys and Questionnaires ,Original Reports ,medicine ,Clinical endpoint ,Humans ,Prospective Studies ,030223 otorhinolaryngology ,Adverse effect ,Aged ,Rhinitis ,business.industry ,Minimal clinically important difference ,Incidence (epidemiology) ,nonallergic rhinitis ,Cryoablation ,Middle Aged ,medicine.disease ,posterior nasal nerve cryoablation ,Nasal Mucosa ,Treatment Outcome ,030228 respiratory system ,Otorhinolaryngology ,chronic rhinitis ,Chronic Disease ,Quality of Life ,Female ,Safety ,business ,cryotherapy ,Follow-Up Studies - Abstract
OBJECTIVES/HYPOTHESIS To assess the long-term (12-24 months) safety and effectiveness of cryoablation of the posterior nasal nerve as treatment for chronic rhinitis. STUDY DESIGN A multicenter, prospective, single-arm clinical study. METHODS The study was conducted from February 2017 to April 2020. Study endpoints included change from baseline in the reflective Total Nasal Symptom Score (rTNSS), Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ), physician assessment of improvement using the Clinical Global Impression-Improvement (CGI-I), and the incidence of treatment-related adverse events. RESULTS Ninety-one participants completed the study through the initial 12-month study period. Sixty-two participants consented to the long-term follow-up with 57 completing the 24-month follow-up. Significant improvements in the total rTNSS were reflected in a median change from baseline of -3.0 or -4.0 at all timepoints (P
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- 2021
7. CD10 marks non-canonical PPARγ-independent adipocyte maturation and browning potential of adipose-derived stem cells
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Paul M. Yen, K. N. Bhanu Prakash, Shigeki Sugii, Wee Kiat Ong, Winifred W. Yau, Weiping Han, Smarajit Chakraborty, Zhihong Zhou, and Sue-Anne Toh
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Lipolytic pathways ,medicine.medical_treatment ,Cell ,Retinoic acid ,Medicine (miscellaneous) ,Adipose tissue ,Biomarker, adipogenesis ,Biology ,Biochemistry, Genetics and Molecular Biology (miscellaneous) ,lcsh:Biochemistry ,chemistry.chemical_compound ,Quality, adipose-derived mesenchymal stem cells ,immune system diseases ,Adipocyte ,hemic and lymphatic diseases ,Adipocytes ,medicine ,Drug screening, nuclear receptor superfamily ,Humans ,Lipid droplets accumulation ,lcsh:QD415-436 ,Prospective Studies ,Cells, Cultured ,Gene knockdown ,lcsh:R5-920 ,Adipogenesis ,Research ,Stem Cells ,Cell Differentiation ,Cell Biology ,Stem-cell therapy ,Cell biology ,PPAR gamma ,Seahorse analysis, oxidative metabolism ,medicine.anatomical_structure ,chemistry ,Neprilysin, NEP, MME ,Molecular Medicine ,Adipocytes, non-canonical activation ,Neprilysin ,Stem cell ,lcsh:Medicine (General) ,Adipocytes, beige - Abstract
Background Effective stem cell therapy is dependent on the stem cell quality that is determined by their differentiation potential, impairment of which leads to poor engraftment and survival into the target cells. However, limitations in our understanding and the lack of reliable markers that can predict their maturation efficacies have hindered the development of stem cells as an effective therapeutic strategy. Our previous study identified CD10, a pro-adipogenic, depot-specific prospective cell surface marker of human adipose-derived stem cells (ASCs). Here, we aim to determine if CD10 can be used as a prospective marker to predict mature adipocyte quality and play a direct role in adipocyte maturation. Methods We first generated 14 primary human subject-derived ASCs and stable immortalized CD10 knockdown and overexpression lines for 4 subjects by the lentiviral transduction system. To evaluate the role of CD10 in adipogenesis, the adipogenic potential of the human subject samples were scored against their respective CD10 transcript levels. Assessment of UCP1 expression levels was performed to correlate CD10 levels to the browning potential of mature ASCs. Quantitative polymerase chain reaction (qPCR) and Western blot analysis were performed to determine CD10-dependent regulation of various targets. Seahorse analysis of oxidative metabolism and lipolysis assay were studied. Lastly, as a proof-of-concept study, we used CD10 as a prospective marker for screening nuclear receptor ligands library. Results We identified intrinsic CD10 levels as a positive determinant of adipocyte maturation as well as browning potential of ASCs. Interestingly, CD10 regulates ASC’s adipogenic maturation non-canonically by modulating endogenous lipolysis without affecting the classical peroxisome proliferator-activated receptor gamma (PPARγ)-dependent adipogenic pathways. Furthermore, our CD10-mediated screening analysis identified dexamethasone and retinoic acid as stimulator and inhibitor of adipogenesis, respectively, indicating CD10 as a useful biomarker for pro-adipogenic drug screening. Conclusion Overall, we establish CD10 as a functionally relevant ASC biomarker, which may be a prerequisite to identify high-quality cell populations for improving metabolic diseases.
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- 2021
8. Autophagic protein ULK1 regulates FOXM1 signalling in human hepatoma cells
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Rohit A. Sinha, Sangam Rajak, Paul M. Yen, Archana Tewari, Sana Raza, Shivmurat Yadav, and Sujoy Ghosh
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0301 basic medicine ,Carcinoma, Hepatocellular ,Biophysics ,Biology ,Biochemistry ,Transcriptome ,03 medical and health sciences ,0302 clinical medicine ,Autophagy ,Autophagy-Related Protein-1 Homolog ,Humans ,Gene Silencing ,Molecular Biology ,Cell Proliferation ,Kinase ,Forkhead Box Protein M1 ,Liver Neoplasms ,Intracellular Signaling Peptides and Proteins ,Hep G2 Cells ,Cell Biology ,Cell cycle ,ULK1 ,digestive system diseases ,030104 developmental biology ,Signalling ,030220 oncology & carcinogenesis ,Hepg2 cells ,FOXM1 ,Cancer research ,Signal Transduction - Abstract
Hepatocellular cancer (HCC) is one of the leading causes of mortality worldwide. Unfortunately, a limited choice of anti-cancer drugs is available for treatment, owing to their minimal efficacy and development of acquired resistance. Autophagy, a cellular survival pathway, often exhibits a pleiotropic role in HCC progression. Studies show increased autophagy in established HCC, promoting the survival of HCC cells in the tumour microenvironment. Therefore, novel anti-autophagy drugs hold promise for preventing HCC progression. Here, using a non-biased transcriptomics analysis in HepG2 cells we demonstrate the existence of an autophagy-FOXM1 nexus regulating growth in HepG2 cells. Additionally, we show that suppression of autophagy by an Unc-51 Like Autophagy Activating Kinase 1(ULK1) inhibitor not only attenuates the expression of FOXM1 and its transcriptional targets, but also has a synergistic effect on the inhibition of HepG2 growth when combined with FOXM1 inhibitors. Thus, the autophagic protein, ULK1, is a promising candidate for preventing HCC progression. Collectively, our results provide new insight into the role of autophagy in HCC growth and are a proof-of concept for combinatorial therapy using ULK1 and FOXM1 inhibitors.
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- 2020
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9. Profiling retrospective thyroid function data in complete thyroidectomy patients to investigate the HPT axis set point (PREDICT-IT)
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Paul M. Yen, E Li, Johannes W. Dietrich, and M K-S Leow
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endocrine system ,education.field_of_study ,endocrine system diseases ,medicine.diagnostic_test ,business.industry ,Endocrinology, Diabetes and Metabolism ,Thyroid disease ,Population ,030209 endocrinology & metabolism ,medicine.disease ,Thyroid function tests ,Hypothalamic–pituitary–thyroid axis ,Set point ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,030220 oncology & carcinogenesis ,Medicine ,Complete thyroidectomy ,Euthyroid ,Thyroid function ,business ,education ,Nuclear medicine ,hormones, hormone substitutes, and hormone antagonists - Abstract
The homeostatic euthyroid set point of the hypothalamus–pituitary–thyroid axis of any given individual is unique and oscillates narrowly within substantially broader normal population ranges of circulating free thyroxine (FT4) and thyroid-stimulating hormone (TSH), otherwise termed ‘thyroid function test (TFT)’. We developed a mathematical algorithm codenamed Thyroid-SPOT that effectively reconstructs the personalized set point in open-loop situations and evaluated its performance in a retrospective patient sample. We computed the set points of 101 patients who underwent total thyroidectomy for non-functioning thyroid disease using Thyroid-SPOT on each patient’s own serial post-thyroidectomy TFT. Every predicted set point was compared against its respective healthy pre-operative euthyroid TFT per individual and their separation (i.e. predicted–observed TFT) quantified. Bland–Altman analysis to measure the agreement between each pair of an individual’s predicted and actual set points revealed a mean difference in FT4 and TSH of + 3.03 pmol/L (95% CI 2.64, 3.43) and − 0.03 mIU/L (95% CI − 0.25, 0.19), respectively. These differences are small compared to the width of the reference intervals. Thyroid-SPOT can predict the euthyroid set point remarkably well, especially for TSH with a 10–16-fold spread in magnitude between population normal limits. Every individual’s equilibrium euthyroid set point is unique. Thyroid-SPOT serves as an accurate, precise and reliable targeting system for optimal personalized restoration of euthyroidism. This algorithm can guide clinicians in L-thyroxine dose titrations to resolve persistent dysthyroid symptoms among challenging cases harbouring “normal TFT” within the laboratory ranges but differing significantly from their actual euthyroid set points.
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- 2020
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10. Decreased autophagy and fuel switching occur in a senescent hepatic cell model system
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Paul M. Yen, Jin Zhou, Brijesh K. Singh, Reddemma Sandireddy, Keziah Tikno, and Madhulika Tripathi
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Male ,Senescence ,Aging ,Cell signaling ,senescence ,Glutamine ,liver ,medicine.disease_cause ,Cell Line ,Hepatitis ,Mice ,Insulin resistance ,Autophagy ,medicine ,Animals ,Glycolysis ,Cellular Senescence ,Chemistry ,TOR Serine-Threonine Kinases ,Cell Biology ,Lipid Metabolism ,medicine.disease ,Cell biology ,Mice, Inbred C57BL ,Oxidative Stress ,Phenotype ,Gene Expression Regulation ,AML12 cells ,Hepatocytes ,Hepatic stellate cell ,Energy Metabolism ,metabolism ,Oxidative stress ,Research Paper - Abstract
Although aging in the liver contributes to the development of chronic liver diseases such as NAFLD and insulin resistance, little is known about the molecular and metabolic details of aging in hepatic cells. To examine these issues, we used sequential oxidative stress with hydrogen peroxide to induce premature senescence in AML12 hepatic cells. The senescent cells exhibited molecular and metabolic signatures, increased SA-βGal and γH2A.X staining, and elevated senescence and pro-inflammatory gene expression that resembled livers from aged mice. Metabolic phenotyping showed fuel switching towards glycolysis and mitochondrial glutamine oxidation as well as impaired energy production. The senescent AML12 cells also had increased mTOR signaling and decreased autophagy which likely contributed to the fuel switching from β-oxidation that occurred in normal AML12 cells. Additionally, senescence-associated secretory phenotype (SASP) proteins from conditioned media of senescent cells sensitized normal AML12 cells to palmitate-induced toxicity, a known pathological effect of hepatic aging. In summary, we have generated senescent AML12 cells which displayed the molecular hallmarks of aging and also exhibited the aberrant metabolic phenotype, mitochondrial function, and cell signaling that occur in the aged liver.
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- 2020
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11. In‐Office Tympanostomy Tube Placement in Children Using Iontophoresis and Automated Tube Delivery
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D. Macy Vidrine, John E. McClay, Erik H. Waldman, Amy Ingram, Amy Brenski, David M. Yen, Lawrence R. Lustig, Robert C. Sprecher, Christopher R. Thompson, Charles A. Syms, Eli Grunstein, Frederick K. Kozak, Neil K. Chadha, Ritvik P. Mehta, Denise A. Sherman, Andrew R. Gould, Laura J. England, Scott R. Schoem, Michael T. Murray, Robert Puchalski, David M. Brown, Dan Harfe, Susannah Hills, Randall A. Ow, John Ansley, Christopher York, John Gavin, Audrey P. Calzada, Jonathan R. Moss, and Jacob W. Zeiders
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Lidocaine ,medicine.medical_treatment ,Sedation ,office surgery ,Myringotomy ,03 medical and health sciences ,0302 clinical medicine ,tympanostomy tube ,030225 pediatrics ,Original Reports ,medicine ,Local anesthesia ,Tympanostomy tube ,030223 otorhinolaryngology ,business.industry ,Iontophoresis ,Publication of this supplement is made possible by Tusker Medical ,pediatric ,Otorhinolaryngology ,Tolerability ,Anesthesia ,myringotomy ,Cohort ,medicine.symptom ,business ,local anesthesia ,Cohort study ,medicine.drug - Abstract
OBJECTIVES/HYPOTHESIS Evaluate technical success, tolerability, and safety of lidocaine iontophoresis and tympanostomy tube placement for children in an office setting. STUDY DESIGN Prospective individual cohort study. METHODS This prospective multicenter study evaluated in-office tube placement in children ages 6 months through 12 years of age. Anesthesia was achieved via lidocaine/epinephrine iontophoresis. Tube placement was conducted using an integrated and automated myringotomy and tube delivery system. Anxiolytics, sedation, and papoose board were not used. Technical success and safety were evaluated. Patients 5 to 12 years old self-reported tube placement pain using the Faces Pain Scale-Revised (FPS-R) instrument, which ranges from 0 (no pain) to 10 (very much pain). RESULTS Children were enrolled into three cohorts with 68, 47, and 222 children in the Operating Room (OR) Lead-In, Office Lead-In, and Pivotal cohorts, respectively. In the Pivotal cohort, there were 120 and 102 children in the
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- 2020
12. Estrogen-related receptor alpha and Rplp1-dependent translation coordinately regulate starvation response and decrease NASH progression
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Pierce K. H. Chow, Vincent Giguère, Jin Zhou, Keziah Tikno, Brijesh K. Singh, Sunghee Park, Donald P. McDonnell, Madhulika Tripathi, Kabilesh Arul, Boon-Huat Bay, Paul M. Yen, Yajun Wu, Karine Gauthier, and Reddemma Sandireddy
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Starvation ,Estrogen-related receptor alpha ,Lipotoxicity ,Autophagy ,medicine ,Hepatic stellate cell ,Translation (biology) ,medicine.symptom ,Biology ,Steatohepatitis ,medicine.disease ,Starvation response ,Cell biology - Abstract
Although general translation declines during fasting, maintaining the translation of a subset or proteins is necessary for metabolic homeostasis and cell viability. Using unbiased proteome analysis of hepatic cells during starvation, we identified a novel pathway in which Esrra-mediated transcription of Rplp1-dependent translation of lysosomal proteins declined during early starvation and recovered after prolonged starvation to restore autophagy-lysosome function. Interestingly, hepatic Esrra-Rplp1-dependent translation rate of lysosomal proteins also was impaired in patients and mice with non-alcoholic steatohepatitis (NASH), and translational response to starvation was dysregulated in mice with NASH. Remarkably, activation of Esrra pharmacologically, genetically, or by alternate day fasting restored protein translation, increased expression of lysosomal proteins, induced autophagy, and reduced lipotoxicity, inflammation, and fibrosis in cell culture andin vivomodels of NASH. Thus, hepatic Esrra is essential for ribosome-dependent translation of lysosomal proteins during starvation, and prevention of lipotoxicity and progression in NASH.Lay summaryFasting for weight loss improves non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH); however, the mechanism is not well understood. Our study shows that a nuclear protein, estrogen related receptor alpha (Esrra), increases ribosome-mediated translation of autophagy and lysosome proteins during chronic starvation to maintain essential metabolic pathways for cell survival. Surprisingly, this translational pathway is impaired during NASH with reduced lysosome-autophagy activity accompanied by increased inflammation and fibrosis gene expression in the liver. Pharmacologic, genetic and dietary activation of Esrra decreases lipid-mediated toxicity in liver cells as well as inflammation and fibrosis in livers from mice with NASH. These findings suggest that the Esrra-ribosome-lysosome pathway is important for liver response to fasting and NASH and thus may be a good therapeutic target for the treatment of NASH.
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- 2021
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13. The roles of autophagy and thyroid hormone in the pathogenesis and treatment of NAFLD
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Jin Zhou, Rohit A. Sinha, and Paul M. Yen
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business.industry ,Autophagy ,Fatty liver ,nutritional and metabolic diseases ,Bioinformatics ,medicine.disease ,thyroid hormone ,digestive system ,Article ,digestive system diseases ,Liver disorder ,mitophagy ,lipid oxidation ,Mitochondrial biogenesis ,Lipid oxidation ,NAFLD ,Mitophagy ,medicine ,Steatosis ,Steatohepatitis ,business - Abstract
Non-alcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disorder worldwide. It comprises simple steatosis and non-alcoholic steatohepatitis (NASH), which can further progress to cirrhosis and hepatocellular carcinoma. The pathogenesis of NAFLD involves genetic, environmental, and endocrine factors, and several molecular mechanisms have been identified. In this review, we discuss the recent findings on the role of autophagy, in particular lipophagy and mitophagy, in hepatic lipid oxidation. We discuss the pre-clinical and clinical evidence suggesting that impairment of autophagy exacerbates NAFLD progression and restoration of autophagy exerts beneficial effects on NAFLD. We discuss how thyroid hormone (TH) simultaneously regulates lipophagy, mitophagy, and mitochondrial biogenesis to increase β-oxidation of fatty acids and reduce steatosis in the liver. Lastly, we discuss the recent clinical progress in using TH or thyromimetics in treating NAFLD/NASH.
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- 2021
14. Early induction of hepatic deiodinase type 1 inhibits hepatosteatosis during NAFLD progression
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Jin Zhou, Anita Boelen, Paul M. Yen, Eveline Bruinstroop, Brijesh K. Singh, Madhulika Tripathi, Winifred W. Yau, Endocrinology, AGEM - Amsterdam Gastroenterology Endocrinology Metabolism, and Endocrinology Laboratory
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0301 basic medicine ,Male ,medicine.medical_specialty ,Cirrhosis ,Steatosis ,Deiodinase ,030209 endocrinology & metabolism ,Mice, Transgenic ,Brief Communication ,Iodide Peroxidase ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Thyroid Hormone Treatment ,Non-alcoholic Fatty Liver Disease ,Internal medicine ,NAFLD ,Nonalcoholic fatty liver disease ,medicine ,Animals ,Molecular Biology ,Cells, Cultured ,Mice, Knockout ,Thyroid ,biology ,business.industry ,Fatty liver ,NASH ,Cell Biology ,medicine.disease ,RC31-1245 ,digestive system diseases ,Mice, Inbred C57BL ,030104 developmental biology ,Endocrinology ,medicine.anatomical_structure ,Liver ,biology.protein ,Hepatic stellate cell ,Hepatocytes ,Steatohepatitis ,business ,Hormone - Abstract
Objective Nonalcoholic fatty liver disease (NAFLD) comprises a spectrum ranging from hepatosteatosis to progressive nonalcoholic steatohepatitis that can lead to cirrhosis. Humans with low levels of prohormone thyroxine (T4) have a higher incidence of NAFLD, and thyroid hormone treatment is very promising in all patients with NAFLD. Deiodinase type 1 (Dio1) is a hepatic enzyme that converts T4 to the bioactive T3 and therefore regulates thyroid hormone availability within hepatocytes. We investigated the role of this intrahepatic regulation during the progression of NAFLD. Methods We investigated hepatic thyroid hormone metabolism in two NAFLD models: wild-type mice fed a Western diet with fructose and Leprdb mice fed a methionine- and choline-deficient diet. AAV8-mediated liver-specific Dio1 knockdown was employed to investigate the role of Dio1 during the progression of NAFLD. Intrahepatic thyroid hormone levels, deiodinase activity, and metabolic parameters were measured. Results Dio1 expression and activity were increased in the early stages of NAFLD and were associated with an increased T3/T4 ratio. Prevention of this increase by AAV8-mediated liver-specific Dio1 knockdown increased hepatic triglycerides and cholesterol and decreased the pACC/ACC ratio and acylcarnitine levels, suggesting there was lower β-oxidation. Dio1 siRNA KD in hepatic cells treated with fatty acids showed increased lipid accumulation and decreased oxidative phosphorylation. Conclusion Hepatic Dio1 gene expression was modulated by dietary conditions, was increased during hepatosteatosis and early NASH, and regulated hepatic triglyceride content. These early adaptations likely represent compensatory mechanisms that reduce hepatosteatosis and prevent NASH progression., Graphical abstract Image 1, Highlights • Low thyroid hormone action is implicated in the pathogenesis of NAFLD. • Intracellular thyroid hormone concentrations are regulated by deiodinases. • Increased deiodinase 1 was found in early NAFLD increasing T3/T4 ratio. • AAV8 mediated liver specific knockdown of deiodinase 1 increases steatosis.
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- 2021
15. Thyroid Hormone Receptor α Regulates Autophagy, Mitochondrial Biogenesis, and Fatty Acid Use in Skeletal Muscle
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Xuguang Zhu, Rohit A. Sinha, Jia Pei Ho, Paul M. Yen, Cho Rong Han, Karine Gauthier, Sheue-yann Cheng, Andrea Lim, Jin Zhou, Institut de Génomique Fonctionnelle de Lyon (IGFL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), and École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL)
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Male ,0301 basic medicine ,muscle ,Endocrinology, Diabetes and Metabolism ,[SDV]Life Sciences [q-bio] ,Cathepsin D ,Bioinformatics ,Cathepsin B ,MESH: Hypothyroidism ,Mice ,0302 clinical medicine ,Endocrinology ,TRα1 mutation ,lipid metabolism ,MESH: Animals ,Receptor ,Research Articles ,MESH: Lipid Metabolism ,MESH: Muscle, Skeletal ,Chemistry ,MESH: Energy Metabolism ,Mitochondrial Turnover ,MESH: Mitochondrial Turnover ,Cell biology ,medicine.anatomical_structure ,Thyroid Hormone Receptors alpha ,medicine.medical_specialty ,autophagy ,MESH: Mutation ,Skeletal muscle weakness ,MEDLINE ,MESH: Thyroid Hormone Receptors alpha ,030209 endocrinology & metabolism ,03 medical and health sciences ,Hypothyroidism ,mitochondrial function ,Internal medicine ,medicine ,Animals ,Humans ,MESH: Autophagy ,Muscle, Skeletal ,MESH: Mice ,Thyroid hormone receptor ,business.industry ,Autophagy ,Skeletal muscle ,TFAM ,MESH: Male ,030104 developmental biology ,Mitochondrial biogenesis ,Mutation ,Energy Metabolism ,business - Abstract
Skeletal muscle (SM) weakness occurs in hypothyroidism and resistance to thyroid hormone α (RTHα) syndrome. However, the cell signaling and molecular mechanism(s) underlying muscle weakness under these conditions is not well understood. We thus examined the role of thyroid hormone receptor α (TRα), the predominant TR isoform in SM, on autophagy, mitochondrial biogenesis, and metabolism to demonstrate the molecular mechanism(s) underlying muscle weakness in these two conditions. Two genetic mouse models were used in this study: TRα1PV/+ mice, which express the mutant Thra1PV gene ubiquitously, and SM-TRα1L400R/+ mice, which express TRα1L400R in a muscle-specific manner. Gastrocnemius muscle from TRα1PV/+, SM-TRα1L400R/+, and their control mice was harvested for analyses. We demonstrated that loss of TRα1 signaling in gastrocnemius muscle from both the genetic mouse models led to decreased autophagy as evidenced by accumulation of p62 and decreased expression of lysosomal markers (lysosomal-associated membrane protein [LAMP]-1 and LAMP-2) and lysosomal proteases (cathepsin B and cathepsin D). The expression of peroxisome proliferator-activated receptor γ coactivator 1α (PGC1α), mitochondrial transcription factor A (TFAM), and estrogen-related receptor α (ERRα), key factors contributing to mitochondrial biogenesis as well as mitochondrial proteins, were decreased, suggesting that there was reduced mitochondrial biogenesis due to the expression of mutant TRα1. Transcriptomic and metabolomic analyses of SM suggested that lipid catabolism was impaired and was associated with decreased acylcarnitines and tricarboxylic acid cycle intermediates in the SM from the mouse line expressing SM-specific mutant TRα1. Our results provide new insight into TRα1-mediated cell signaling, molecular, and metabolic changes that occur in SM when TR action is impaired.
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- 2021
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16. Links between autophagy and disorders of glycogen metabolism – Perspectives on pathogenesis and possible treatments
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Benjamin L. Farah, Dwight D. Koeberl, and Paul M. Yen
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0301 basic medicine ,Endocrinology, Diabetes and Metabolism ,Glycogenolysis ,Glycogen Storage Disease Type I ,030105 genetics & heredity ,Biology ,Mitochondrion ,Biochemistry ,Article ,Pathogenesis ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Endocrinology ,Autophagy ,Genetics ,Animals ,Humans ,Muscle, Skeletal ,Molecular Biology ,chemistry.chemical_classification ,Glycogen ,Glycogen Storage Disease Type II ,Glycogen metabolism ,Glycogen Storage Disease ,Cell biology ,Enzyme ,chemistry ,030217 neurology & neurosurgery ,Intracellular ,Function (biology) - Abstract
The glycogen storage diseases are a group of inherited metabolic disorders that are characterized by specific enzymatic defects involving the synthesis or degradation of glycogen. Each disorder presents with a set of symptoms that are due to the underlying enzyme deficiency and the particular tissues that are affected. Autophagy is a process by which cells degrade and recycle unneeded or damaged intracellular components such as lipids, glycogens, and damaged mitochondria. Recent studies showed that several of the glycogen storage disorders have abnormal autophagy which can disturb normal cellular metabolism and/or mitochondrial function. Here, we provide a clinical overview of the glycogen storage disorders, a brief description of autophagy, and the known links between specific glycogen storage disorders and autophagy.
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- 2020
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17. Nonalcoholic Fatty Liver Disease and Hypercholesterolemia: Roles of Thyroid Hormones, Metabolites, and Agonists
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Paul M. Yen, Brijesh K. Singh, Eveline Bruinstroop, and Rohit A. Sinha
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Thyroid Hormones ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,Hypercholesterolemia ,030209 endocrinology & metabolism ,Article ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Endocrinology ,Non-alcoholic Fatty Liver Disease ,Internal medicine ,Nonalcoholic fatty liver disease ,medicine ,Animals ,Humans ,Receptors, Thyroid Hormone ,Triiodothyronine ,Triglyceride ,business.industry ,Cholesterol ,Lipid metabolism ,Lipid Metabolism ,medicine.disease ,Hypothalamic–pituitary–thyroid axis ,Liver ,chemistry ,030220 oncology & carcinogenesis ,business ,Hormone ,Lipoprotein - Abstract
BACKGROUND: Thyroid hormones (THs) exert a strong influence on mammalian lipid metabolism at the systemic and hepatic levels by virtue of their roles in regulating circulating lipoprotein, triglyceride (TAG), and cholesterol levels, as well as hepatic TAG storage and metabolism. These effects are mediated by intricate sensing and feedback systems that function at the physiological, metabolic, molecular, and transcriptional levels in the liver. Dysfunction in the pathways involved in lipid metabolism disrupts hepatic lipid homeostasis and contributes to the pathogenesis of metabolic diseases, such as nonalcoholic fatty liver disease (NAFLD) and hypercholesterolemia. There has been strong interest in understanding and employing THs, TH metabolites, and TH mimetics as lipid-modifying drugs. SUMMARY: THs regulate many processes involved in hepatic TAG and cholesterol metabolism to decrease serum cholesterol and intrahepatic lipid content. TH receptor β analogs designed to have less side effects than the natural hormone are currently being tested in phase II clinical studies for NAFLD and hypercholesterolemia. The TH metabolites, 3,5-diiodo-l-thyronine (T2) and T1AM (3-iodothyronamine), have different beneficial effects on lipid metabolism compared with triiodothyronine (T3), although their clinical application is still under investigation. Also, prodrugs and glucagon/T3 conjugates have been developed that direct TH to the liver. CONCLUSIONS: TH-based therapies show clinical promise for the treatment of NAFLD and hypercholesterolemia. Strategies for limiting side effects of TH are being developed and may enable TH metabolites and analogs to have specific effects in the liver for treatments of these conditions. These liver-specific effects and potential suppression of the hypothalamic/pituitary/thyroid axis raise the issue of monitoring liver-specific markers of TH action to assess clinical efficacy and dosing of these compounds.
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- 2019
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18. Titin truncations lead to impaired cardiomyocyte autophagy and mitochondrial function in vivo
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Rohit A. Sinha, Andrea Lim, Benjamin Ng, Jin Zhou, Sebastian Schafer, Paul M. Yen, Yajun Wu, Lorna R. Fiedler, Nicole S. J. Ko, Ester Khin, Boon-Huat Bay, Stuart A. Cook, Sonia Chothani, and Norliza E Sahib
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Male ,mTORC1 ,connectin ,Mitochondrion ,mtor serine-threonine kinases ,ventricular remodeling ,Mitochondria, Heart ,Cathepsin B ,Sequestosome-1 Protein ,Myocytes, Cardiac ,Cells, Cultured ,Genetics (clinical) ,Heart metabolism ,Sequence Deletion ,chemistry.chemical_classification ,education.field_of_study ,TOR Serine-Threonine Kinases ,cathepsin b ,catabolism ,General Medicine ,proteolytic enzymes ,mechanistic target of rapamycin complex 1 ,Cell biology ,endopeptidases ,mitochondria ,mitochondrial proteins ,Microtubule-Associated Proteins ,Cardiomyopathy, Dilated ,autophagy ,cardiac myocytes ,Population ,heart ,Biology ,Genetics ,medicine ,Animals ,Ventricular remodeling ,education ,Molecular Biology ,acetylation ,Reactive oxygen species ,rapamycin ,Autophagy ,Ubiquitination ,NAD ,medicine.disease ,rats ,chemistry ,nicotinamide adenine dinucleotide (nad) ,cardiac function ,Reactive Oxygen Species ,autophagosomes ,metabolism - Abstract
Titin-truncating variants (TTNtv) are the most common genetic cause of dilated cardiomyopathy. TTNtv occur in ~1% of the general population and causes subclinical cardiac remodeling in asymptomatic carriers. In rat models with either proximal or distal TTNtv, we previously showed altered cardiac metabolism at baseline and impaired cardiac function in response to stress. However, the molecular mechanism(s) underlying these effects remains unknown. In the current study, we used rat models of TTNtv to investigate the effect of TTNtv on autophagy and mitochondrial function, which are essential for maintaining cellular metabolic homeostasis and cardiac function. In both the proximal and distal TTNtv rat models, we found increased levels of LC3B-II and p62 proteins, indicative of diminished autophagic degradation. The accumulation of autophagosomes and p62 protein in cardiomyocytes was also demonstrated by electron microscopy and immunochemistry, respectively. Impaired autophagy in the TTNtv heart was associated with increased phosphorylation of mTOR and decreased protein levels of the lysosomal protease, cathepsin B. In addition, TTNtv hearts showed mitochondrial dysfunction, as evidenced by decreased oxygen consumption rate in cardiomyocytes, increased levels of reactive oxygen species and mitochondrial protein ubiquitination. We also observed increased acetylation of mitochondrial proteins associated with decreased NAD+/NADH ratio in the TTNtv hearts. mTORC1 inhibitor, rapamycin, was able to rescue the impaired autophagy in TTNtv hearts. In summary, TTNtv leads to impaired autophagy and mitochondrial function in the heart. These changes not only provide molecular mechanisms that underlie TTNtv-associated ventricular remodeling but also offer potential targets for its intervention.
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- 2019
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19. P06.06.B standardization of therapy and manufacturing using tumor-associated antigen-stimulated autologous dendritic cells co-cultured with cytokine-induced killer cells in cancer immunotherapy
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C M Yen, Y Y Fu, and M Y Yang
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Cancer Research ,Oncology ,Neurology (clinical) - Abstract
Background The application of DC-CIK in the field of cancer immunotherapy has been shown to be an effective treatment. However, the cost of DC-CIK treatment is prohibitive for many patients, and the lack of standard manufacturing processes and treatment strategies are the main limitations. Material and Methods Our experiments used tumor lysate instead of tumor cell line as tumor-associated antigen source with DCs co-culture. We provide the most efficient method for obtaining autologous DC-CIK cells from peripheral blood. Flow cytometry was used to evaluate DCs activation, CBA assay was used to quantify cytokines secreted by CIK cells, and the antitumor activity of DC-CIK was evaluated in vitro by K562 cell line. Results We demonstrate that the manufacturing process of employing frozen Peripheral Blood Mononuclear Cells (PBMCs) can balance patient’s comfort and economic benefits. DC-CIK can effectively upgrade the immunological specificity of CIK cells to tumors in the presence of tumor-associated antigen. In vitro experiments showed that when the number of DC: CIK cells was co-cultured in 1:20 ratio on the 14th day, the amount of cytokine secreted by CIK cells was the largest, and the anti-tumor immune effect was the most potent. When the number of CIK: K562 cells was in 25:1 ratio, the cytotoxic activity of CIK on K562 cells was the highest. Conclusion We developed an efficient activated fashion of DC:CIK, established the optimal ratio of DC-CIK immunologic activity and the best cytotoxic model of CIK to K562 cells.
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- 2022
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20. Increased Hepatic Fat Content in Patients with Resistance to Thyroid Hormone Beta
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João Anselmo, Paul M. Yen, Eveline Bruinstroop, Samuel Refetoff, Carolina Chaves, Endocrinology, and Amsterdam Gastroenterology Endocrinology Metabolism
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Adult ,Male ,Thyroid Hormone Resistance Syndrome ,medicine.medical_specialty ,Adolescent ,Endocrinology, Diabetes and Metabolism ,Thyroid Economy: Regulation, Cell Biology, and Thyroid Hormone Metabolism and Action ,Thyroid hormone receptor beta ,Young Adult ,Endocrinology ,Insulin resistance ,Internal medicine ,Nonalcoholic fatty liver disease ,medicine ,Humans ,thyroid hormones ,business.industry ,hepatic steatosis ,Thyroid ,Correction ,Thyroid Hormone Receptors beta ,Middle Aged ,medicine.disease ,transient elastography ,resistance to thyroid hormone beta ,Fatty Liver ,medicine.anatomical_structure ,Adipose Tissue ,Liver ,Mutation ,Homeostatic model assessment ,Female ,Steatosis ,Insulin Resistance ,Transient elastography ,business ,Hormone - Abstract
Background: Thyroid hormone (TH) has important functions in controlling hepatic lipid metabolism. Individuals with resistance to thyroid hormone beta (RTHβ) who harbor mutations in the THRB gene experience loss-of-function of thyroid hormone receptor beta (TRβ), which is the predominant TR isoform expressed in the liver. We hypothesized that individuals with RTHβ may have increased hepatic steatosis. Methods: Controlled attenuation parameter (CAP) was assessed in individuals harboring the R243Q mutation of the THRB gene (n = 21) and in their wild-type (WT) first-degree relatives (n = 22) using the ultrasound-based transient elastography (TE) device (FibroScan). All participants belonged to the same family, lived on the same small island, and were therefore exposed to similar environmental conditions. CAP measurements and blood samples were obtained after an overnight fast. The observers were blinded to the status of the patients. Results: The hepatic fat content was increased in RTHβ individuals compared with their WT relatives (CAP values of 263 ± 21 and 218.7 ± 43 dB/m, respectively, p = 0.007). The CAP values correlated with age and body mass index (BMI) (age: r = 0.55, p = 0.011; BMI: r = 0.51, p = 0.022) in the WT first-degree relatives but not in RTHβ individuals, suggesting that the defect in TRβ signaling was predominant over the effects of age and obesity. Circulating free fatty acid levels were significantly higher in RTHβ individuals (0.29 ± 0.033 vs. 0.17 ± 0.025 mmol/L, p = 0.02). There was no evidence of insulin resistance evaluated by the homeostatic model assessment of insulin resistance in both groups studied. Conclusions: Our findings provide evidence that impairments in intrahepatic TRβ signaling due to mutations of the THRB gene can lead to hepatic steatosis, which emphasizes the influence of TH in the liver metabolism of lipids and provides a rationale for the development TRβ-selective thyromimetics. Consequently, new molecules with a very high TRβ affinity and hepatic selectivity have been developed for the treatment of lipid-associated hepatic disorders, particularly nonalcoholic fatty liver disease.
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- 2021
21. Temperature-controlled radiofrequency device treatment of the nasal valve for nasal airway obstruction: A randomized controlled trial
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Chad M. McDuffie, David M Yen, Stacey L. Silvers, Joseph K. Han, and Jon N Rosenthal
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business.industry ,Temperature ,Nasal congestion ,Nose ,Confidence interval ,law.invention ,Nasal valve ,medicine.anatomical_structure ,Treatment Outcome ,Otorhinolaryngology ,Randomized controlled trial ,law ,Anesthesia ,medicine ,Clinical endpoint ,Immunology and Allergy ,Humans ,Nasal Airway Obstruction ,Prospective Studies ,medicine.symptom ,Nasal Obstruction ,business ,Adverse effect - Abstract
BACKGROUND Nasal valve collapse is one of several causes of nasal obstruction. The safety and efficacy of a temperature-controlled radiofrequency (RF) device for the treatment of the nasal valve for nasal airway obstruction (NAO) has been established in single-arm studies. The objective of this trial was to compare active device treatment against a sham procedure (control). METHODS In a prospective, multicenter, single-blinded, randomized controlled trial (RCT), patients were assigned to bilateral temperature-controlled RF treatment of the nasal valve (n = 77) or a sham procedure (n = 41), in which no RF energy was transferred to the device/treatment area. The device was applied to the mucosa over the lower lateral cartilage on the lateral nasal wall. The primary endpoint was responder rate at 3 months, defined as a ≥20% reduction in Nasal Obstruction Symptom Evaluation (NOSE)-scale score or ≥1 reduction in clinical severity category. RESULTS At baseline, patients had a mean NOSE-scale score of 76.7 (95% confidence interval [CI], 73.8 to 79.5) and 78.8 (95% CI, 74.2 to 83.3) (p = 0.424) in the active treatment and sham-control arms, respectively. At 3 months, the responder rate was significantly higher in the active treatment arm (88.3% [95% CI, 79.2%-93.7%] vs 42.5% [95% CI, 28.5%-57.8%]; p
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- 2021
22. Redefining IL11 as a regeneration-limiting hepatotoxin and therapeutic target in acetaminophen-induced liver injury
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Sonia Chothani, Leroy S. Pakkiri, Robert George Edward Holgate, Stuart A. Cook, Anissa A. Widjaja, Leanne E. Felkin, Joyce Sze Yuin Goh, Jin Zhou, Jessie Tan, Shamini Guna Shekeran, Brijesh K. Singh, James W. Dear, Chester L. Drum, Paul M. Yen, Mao Wang, Arron Hearn, Sivakumar Viswanathan, Eleonora Adami, Jinrui Dong, Benjamin K Ng, Sze Yun Lim, Sebastian Schafer, and W. Lim
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0301 basic medicine ,MAPK/ERK pathway ,Pharmacology ,03 medical and health sciences ,Mice ,0302 clinical medicine ,medicine ,Animals ,Interleukin-11 Receptor alpha Subunit ,Autocrine signalling ,Acetaminophen ,Liver injury ,NADPH oxidase ,biology ,Kinase ,Chemistry ,digestive, oral, and skin physiology ,Hepatotoxin ,NOX4 ,General Medicine ,medicine.disease ,Interleukin-11 ,Mice, Inbred C57BL ,030104 developmental biology ,medicine.anatomical_structure ,Liver ,Hepatocyte ,Chemical and Drug Induced Liver Injury, Chronic ,biology.protein ,Hepatocytes ,030211 gastroenterology & hepatology ,Chemical and Drug Induced Liver Injury - Abstract
Acetaminophen (N-acetyl-p-aminophenol; APAP) toxicity is a common cause of liver damage. In the mouse model of APAP-induced liver injury (AILI), interleukin 11 (IL11) is highly up-regulated and administration of recombinant human IL11 (rhIL11) has been shown to be protective. Here, we demonstrate that the beneficial effect of rhIL11 in the mouse model of AILI is due to its inhibition of endogenous mouse IL11 activity. Our results show that species-matched IL11 behaves like a hepatotoxin. IL11 secreted from APAP-damaged human and mouse hepatocytes triggered an autocrine loop of NADPH oxidase 4 (NOX4)–dependent cell death, which occurred downstream of APAP-initiated mitochondrial dysfunction. Hepatocyte-specific deletion of Il11 receptor subunit alpha chain 1 (Il11ra1) in adult mice protected against AILI despite normal APAP metabolism and glutathione (GSH) depletion. Mice with germline deletion of Il11 were also protected from AILI, and deletion of Il1ra1 or Il11 was associated with reduced c-Jun N-terminal kinase (JNK) and extracellular signal–regulated kinase (ERK) activation and quickly restored GSH concentrations. Administration of a neutralizing IL11RA antibody reduced AILI in mice across genetic backgrounds and promoted survival when administered up to 10 hours after APAP. Inhibition of IL11 signaling was associated with the up-regulation of markers of liver regenerations: cyclins and proliferating cell nuclear antigen (PCNA) as well as with phosphorylation of retinoblastoma protein (RB) 24 hours after AILI. Our data suggest that species-matched IL11 is a hepatotoxin and that IL11 signaling might be an effective therapeutic target for APAP-induced liver damage.
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- 2021
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23. Cryotherapy for treatment of chronic rhinitis: 3-month outcomes of a randomized, sham-controlled trial
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Rodney J. Schlosser, Joseph L. Russell, Anthony Del Signore, Ellen M O'Malley, Joshua B. Greene, and David M Yen
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Adult ,medicine.medical_treatment ,Cryotherapy ,Nasal congestion ,law.invention ,Randomized controlled trial ,law ,medicine ,Clinical endpoint ,Immunology and Allergy ,Humans ,Local anesthesia ,Prospective Studies ,Adverse effect ,Nose ,Rhinitis ,rhinorrhea ,business.industry ,medicine.anatomical_structure ,Treatment Outcome ,Otorhinolaryngology ,Anesthesia ,Quality of Life ,medicine.symptom ,business - Abstract
BACKGROUND The purpose of this study was to test whether cryotherapy is superior to a sham procedure for reducing symptoms of chronic rhinitis. METHODS This study was a prospective, multicenter, 1:1 randomized, sham-controlled, patient-blinded trial. The predetermined sample size was 61 participants per arm. Adults with moderate/severe symptoms of chronic rhinitis who were candidates for cryotherapy under local anesthesia were enrolled. Participants were required to have minimum reflective Total Nasal Symptom Scores (rTNSSs) of 4 for total, 2 for rhinorrhea, and 1 for nasal congestion. Follow-up visits occurred at 30 and 90 days postprocedure. Patient-reported outcome measures included the rTNSS, standardized Rhinoconjunctivitis Quality of Life Questionnaire [RQLQ(S)], and Nasal Obstruction Symptom Evaluation (NOSE) questionnaires. Adverse events were also recorded. The primary endpoint was the comparison between the treatment and sham arms for the percentage of responders at 90 days. Responders were defined as participants with a 30% or greater reduction in rTNSS relative to baseline. RESULTS Twelve US investigational centers enrolled 133 participants. The primary endpoint analysis included 127 participants (64 active, 63 sham) with 90-day results. The treatment arm was superior at the 90-day follow-up with 73.4% (47 of 64) responders compared with 36.5% (23 of 63) in the sham arm (p < 0.001). There were greater improvements in the rTNSS, RQLQ(S), and NOSE scores for the active arm over the sham arm at the 90-day follow-up (p < 0.001). One serious procedure-related adverse event of anxiety/panic attack was reported. CONCLUSION Cryotherapy is superior to a sham procedure for improving chronic rhinitis symptoms and patient quality of life.
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- 2021
24. Can Tissue Expansion Reconstruction in the Trunk of Children Increase the Risk of Scoliosis?
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Cynthia Verchere, Christopher W. Reilly, Marija Bucevska, and Paul M. Yen
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Tissue expander ,medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,Scoliosis ,Original Articles ,medicine.disease ,Trunk ,Surgery ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,Pediatric surgery ,medicine ,business ,030217 neurology & neurosurgery ,Tissue expansion - Abstract
We hypothesize that treatment of significant truncal lesions with truncal tissue expanders and subsequent flap surgery in pediatric patients may increase the risk of scoliosis. This study aims to investigate any relationship between tissue expansion (TE) and scoliosis and to compare the prevalence of scoliosis in our tissue expander population to the general population.Health records of patients who underwent truncal TE at BC Children's Hospital between 1997 and 2017 were retrospectively reviewed and analyzed. The cross-sectional component of the study consisted of radiological imaging to establish the presence or absence of scoliosis.We identified 28 patients who underwent truncal TE over the study period. Ten had a scoliosis X-ray on their chart or as a part of the study. Three (10.7%) patients were identified as having developed scoliosis after TE.We recommend that pediatric TE patients be made aware of the potential complication of scoliosis and be followed closely in the years during and after their treatment, in order to allow for preventative measures, early diagnosis and early management (if required).Les chercheurs postulent que le traitement d’importantes lésions du tronc par des expandeurs tissulaires suivi d’une opération par lambeau chez les patients pédiatriques peut accroître le risque de scoliose. La présente étude vise à explorer la relation entre l’expansion tissulaire (ET) et la scoliose et à comparer la prévalence de scoliose entre la population ayant subi une expansion tissulaire et la population générale.Les chercheurs ont procédé à l’analyse prospective du dossier de santé des patients qui ont subi une ET du tronc auLes chercheurs ont recensé 28 patients qui ont subi une ET du tronc pendant la période de l’étude. Dix avaient une radiographie de scoliose au dossier ou en cours d’étude. Trois (10,7 %) avaient eu une scoliose après l’ET.Les chercheurs recommandent d’informer les patients pédiatriques qui subissent une ET du tronc qu’ils courent un risque de complication de scoliose et de les suivre de près dans les années où se déroulent le traitement et qui le suivent, afin de favoriser des mesures préventives, des diagnostics précoces et une prise en charge rapide, s’il y a lieu.
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- 2021
25. Chronic cold exposure induces autophagy to promote fatty acid oxidation, mitochondrial turnover, and thermogenesis in brown adipose tissue
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Nivetha Kanakaram Thimmukonda, Paul M. Yen, Kiraely Adam Wong, Jin Zhou, Boon-Huat Bay, Yajun Wu, Winifred W. Yau, and Brijesh K. Singh
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0301 basic medicine ,animal structures ,Mitochondrial Turnover ,Science ,ATG5 ,Endocrine System Physiology ,02 engineering and technology ,Article ,Molecular Physiology ,03 medical and health sciences ,chemistry.chemical_compound ,Mitophagy ,Brown adipose tissue ,medicine ,Beta oxidation ,Multidisciplinary ,Fatty acid metabolism ,Chemistry ,Autophagy ,Cell Biology ,021001 nanoscience & nanotechnology ,Cell biology ,030104 developmental biology ,medicine.anatomical_structure ,0210 nano-technology ,Thermogenesis - Abstract
Summary Autophagy plays an important role in lipid breakdown, mitochondrial turnover, and mitochondrial function during brown adipose tissue (BAT) activation by thyroid hormone, but its role in BAT during adaptive thermogenesis remains controversial. Here, we examined BAT from mice exposed to 72 h of cold challenge as well as primary brown adipocytes treated with norepinephrine and found increased autophagy as well as increased β-oxidation, mitophagy, mitochondrial turnover, and mitochondrial activity. To further understand the role of autophagy of BAT in vivo, we generated BAT-specific Atg5 knockout (Atg5cKO) mice and exposed them to cold for 72 h. Interestingly, BAT-specific Atg5cKO mice were unable to maintain body temperature after chronic cold exposure and displayed deranged mitochondrial morphology and reactive oxygen species damage in their BAT. Our findings demonstrate the critical role of autophagy in adaptive thermogenesis, fatty acid metabolism, and mitochondrial function in BAT during chronic cold exposure., Graphical abstract, Highlights • Chronic cold stress stimulates β-oxidation in BAT to increase thermogenesis • Chronic cold stress stimulates mitophagy in BAT • Autophagy is critical for mitochondrial quality control to sustain thermogenesis, Endocrine System Physiology ; Molecular Physiology ; Cell Biology
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- 2021
26. MTORC1-dependent crinophagy regulates glucagon content in pancreatic α-cells
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Rohit A. Sinha, Paul M. Yen, and Sangam Rajak
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Secretory Vesicles ,Autophagy ,Enteroendocrine cell ,Cell Biology ,mTORC1 ,Mechanistic Target of Rapamycin Complex 1 ,Biology ,Peptide hormone ,Glucagon ,Autophagic Punctum ,Cell biology ,Secretion ,Lysosomes ,Receptor ,Molecular Biology ,Hormone - Abstract
Hormone synthesis and secretion is a highly regulated process governed by metabolic cues. Although peptide hormone action is largely governed by the rate of its synthesis and secretion by endocrine cells, and the levels of its receptors on the target cells, intracellular degradation of the hormone-containing secretory vesicles by lysosomes (crinophagy) adds an additional layer of regulation. In our recent study, we uncovered the regulatory mechanism governing the crinophagic turnover of GCG (glucagon), a glycoprotein hormone secreted by pancreatic α-cells. Our results showed that inhibition of MTORC1 induces crinophagy-mediated degradation of glucagon and decreases its secretion in response to hypoglycemia. Furthermore, we demonstrated that crinophagy-regulated glucagon turnover does not involve macroautophagy. These results suggest that modulation of crinophagy may serve as a novel therapeutic strategy to regulate hormone secretion in endocrine and metabolic pathologies.
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- 2021
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27. Gut microbiota and their metabolites in the progression of non-alcoholic fatty liver disease
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Madhulika Tripathi, Jin Zhou, Rohit A. Sinha, Brijesh K. Singh, and Paul M. Yen
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0301 basic medicine ,Cirrhosis ,gut microbiome ,Disease ,Gut flora ,Bioinformatics ,digestive system ,Article ,Liver disorder ,03 medical and health sciences ,0302 clinical medicine ,Medicine ,gut microbiota metabolites ,Hepatology ,biology ,business.industry ,Fatty liver ,nutritional and metabolic diseases ,medicine.disease ,biology.organism_classification ,digestive system diseases ,030104 developmental biology ,Oncology ,Hepatocellular carcinoma ,030211 gastroenterology & hepatology ,Steatosis ,Steatohepatitis ,business ,Non-alcoholic fatty liver disease - Abstract
Non-alcoholic fatty liver disease (NAFLD) is the most prevalent liver disorder worldwide. It comprises a spectrum of conditions that range from steatosis to non-alcoholic steatohepatitis, with progression to cirrhosis and hepatocellular carcinoma. Currently, there is no FDA-approved pharmacological treatment for NAFLD. The pathogenesis of NAFLD involves genetic and environmental/host factors, including those that cause changes in intestinal microbiota and their metabolites. In this review, we discuss recent findings on the relationship(s) of microbiota signature with severity of NAFLD and the role(s) microbial metabolites in NAFLD progression. We discuss how metabolites may affect NAFLD progression and their potential to serve as biomarkers for NAFLD diagnosis or therapeutic targets for disease management.
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- 2021
28. Hepatocyte-specific IL11 cis-signaling drives lipotoxicity and underlies the transition from NAFLD to NASH
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Sebastian Schafer, Stuart A. Cook, Madhulika Tripathi, Jin Zhou, Eleonora Adami, Jessie Tan, Shamini Guna Shekeran, Sonia Chothani, Nicole S. J. Ko, W. Lim, Anissa A. Widjaja, Brijesh K. Singh, Sivakumar Viswanathan, Jinrui Dong, Paul M. Yen, Mao Wang, Sze Yun Lim, Benjamin Ng, and Pei Min Lio
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0301 basic medicine ,Adult ,Molecular biology ,Science ,General Physics and Astronomy ,Models, Biological ,General Biochemistry, Genetics and Molecular Biology ,Article ,03 medical and health sciences ,Paracrine signalling ,0302 clinical medicine ,Fibrosis ,Non-alcoholic Fatty Liver Disease ,Paracrine Communication ,medicine ,Hepatic Stellate Cells ,Animals ,Humans ,Interleukin-11 Receptor alpha Subunit ,Autocrine signalling ,Cells, Cultured ,Mice, Knockout ,Multidisciplinary ,Hepatology ,Chemistry ,Interleukin-6 ,General Chemistry ,Feeding Behavior ,medicine.disease ,Interleukin-11 ,Lipids ,digestive system diseases ,Autocrine Communication ,Disease Models, Animal ,030104 developmental biology ,medicine.anatomical_structure ,Metabolism ,Phenotype ,Lipotoxicity ,Hepatocyte ,Hepatic stellate cell ,Cancer research ,Hepatocytes ,030211 gastroenterology & hepatology ,Steatosis ,Steatohepatitis ,Signal Transduction - Abstract
IL11 is important for fibrosis in non-alcoholic steatohepatitis (NASH) but its role beyond the stroma in liver disease is unclear. Here, we investigate the role of IL11 in hepatocyte lipotoxicity. Hepatocytes highly express IL11RA and secrete IL11 in response to lipid loading. Autocrine IL11 activity causes hepatocyte death through NOX4-derived ROS, activation of ERK, JNK and caspase-3, impaired mitochondrial function and reduced fatty acid oxidation. Paracrine IL11 activity stimulates hepatic stellate cells and causes fibrosis. In mouse models of NASH, hepatocyte-specific deletion of Il11ra1 protects against liver steatosis, fibrosis and inflammation while reducing serum glucose, cholesterol and triglyceride levels and limiting obesity. In mice deleted for Il11ra1, restoration of IL11 cis-signaling in hepatocytes reconstitutes steatosis and inflammation but not fibrosis. We found no evidence for the existence of IL6 or IL11 trans-signaling in hepatocytes or NASH. These data show that IL11 modulates hepatocyte metabolism and suggests a mechanism for NAFLD to NASH transition., IL11 contributes to the development of non-alcoholic steatohepatitis (NASH) through incompletely understood mechanisms. Here, the authors report that lipotoxicity-driven autocrine IL11 activity underlies hepatocyte metabolic dysfunction and death via a NOX4/ERK-mediated mechanism while paracrine IL11 activity stimulates hepatic stellate cells contributing to fibrosis and inflammation in the context of NASH.
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- 2021
29. MED1 mediator subunit is a key regulator of hepatic autophagy and lipid metabolism
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Rohit A. Sinha, Brijesh K. Singh, Jin Zhou, Jia Pei Ho, Paul M. Yen, Eveline Bruinstroop, Kenji Ohba, Andrea Lim, Endocrinology, and AGEM - Amsterdam Gastroenterology Endocrinology Metabolism
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0301 basic medicine ,Thyroid hormone receptor ,030102 biochemistry & molecular biology ,Autophagy ,starvation ,Mediator Complex Subunit 1 ,Lipid metabolism ,Cell Biology ,Biology ,med1 ,liver ,MED1 ,Cell biology ,03 medical and health sciences ,030104 developmental biology ,Mediator ,Lipid oxidation ,lipid oxidation ,TFEB ,Molecular Biology ,Research Paper - Abstract
Hepatic macroautophagy/autophagy and fatty acid metabolism are transcriptionally regulated by nuclear receptors (NRs); however, it is not known whether their transcriptional co-activators are involved in autophagy. We thus examined MED1 (mediator complex subunit 1), a key component of the Mediator Complex that directly interacts with NRs, on these processes. We found that MED1 knockdown (KD) in cultured hepatic cells decreased autophagy and mitochondrial activity that was accompanied by decreased transcription of genes involved in these processes. Lipophagy and fatty acid β-oxidation also were impaired. These effects also occurred after thyroid hormone stimulation, nutrient-replete or -deplete conditions, and in liver-specific Med1 KD (Med1 LKD) mice under fed and fasting conditions. Together, these findings showed that Med1 played a key role in hepatic autophagy, mitochondria function, and lipid metabolism under these conditions. Additionally, we identified downregulated hepatic genes in Med1 LKD mice, and subjected them to ChIP Enrichment Analysis. Our findings showed that the transcriptional activity of several NRs and transcription factors (TFs), including PPARA and FOXO1, likely were affected by Med1 LKD. Finally, Med1 expression and autophagy also were decreased in two mouse models of nonalcoholic fatty liver disease (NAFLD) suggesting that decreased Med1 may contribute to hepatosteatosis. In summary, MED1 plays an essential role in regulating hepatic autophagy and lipid oxidation during different hormonal and nutrient conditions. Thus, MED1 may serve as an integrator of multiple transcriptional pathways involved in these metabolic processes. Abbreviations: BAF: bafilomycin A(1); db/db mice; Lepr(db/db) mice; ECAR: extracellular acidification rate; KD: knockdown; MED1: mediator complex subunit 1; NAFLD: nonalcoholic fatty liver disease; OCR: oxygen consumption rate; PPARA/PPARα: peroxisomal proliferator activated receptor alpha; TF: transcription factor; TFEB: transcription factor EB; tf-LC3: tandem fluorescence RFP-GFP-LC3; TG: triglyceride; TH: Thyroid hormone; TR: thyroid hormone receptors; V-ATPase: vacuolar-type H(+)-ATPase; WDF: Western diet with 15% fructose in drinking water
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- 2021
30. The demonstration of Carbon Nano-Tubes (CNTs) as a promising high Aspect Ratio (>25) Through Silicon Vias (TSVs) material for the vertical connection in the high dense 3DICs
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C.-W. Hu, P.-Y. Lu, C. Lien, S.-Y. Chang, C.-M. Yen, Chun-Wei Yao, Min-Hung Lee, Ming-Han Liao, and Y.-J. Feng
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Materials science ,Silicon ,Wafer bonding ,Thermal resistance ,chemistry.chemical_element ,Integrated circuit ,Thermal expansion ,law.invention ,Thermal conductivity ,chemistry ,law ,Nano ,Wafer ,Composite material - Abstract
With the excellent material properties of Carbon Nano-tubes (CNTs) developed in this work (Coefficient of Thermal Expansion~-2 x 10-6 K-1, Resistivity~10-6 Ω-m, Young’s modulus~1000 GPa, and thermal conductivity ~800 Wm-1K-1), the real 3D integrated circuits (ICs) system with CNTs as the high aspect ratio (>25)/small diameters ( 5 H 5 ) 2 reactant, (2) Optimized wafer bonding process, (3) Non-mask laser engrave patterning, and (4) wafer transfer technology by a thermal release tape/ethylene viny acetate processes provide the useful solution for the applications of CNTs as a vertical connection material in the near coming high-density 3D device.
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- 2020
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31. Establishing a critical care network in Asia to improve care for critically ill patients in low- and middle-income countries
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R Inglis, Diptesh Aryal, Yoel Lubell, L M Yen, R Moonesinghe, Simon R. Harris, Arjen M. Dondorp, Louise Thwaites, Rashan Haniffa, Marcus J. Schultz, M Leaver, Khamsay Detleuxay, Ahsan Asma., Subhash Prasad Acharya, Gyan Kayastha, Muhammad Hayat, Chairat Permpikul, Nicholas P. J. Day, Arshad Taqi, T Kadhiravan, Lakshmi Ranganathan, L C Har, Mavuto Mukaka, D B Thuy, Syed Muhammad Muneeb Ali, Ishara Udayanga, Guy E. Thwaites, Swagata Tripathy, Madiha Hashmi, D P Khiem, D Priyadarshani, Vijayaraghavan Bkt., Nor Mbm., Abi Beane, R Champunot, R Sultana, Jorge I. F. Salluh, Sophie Yacoub, D Gandy, Christopher Pell, Intensive Care Medicine, Global Health, APH - Health Behaviors & Chronic Diseases, APH - Global Health, ACS - Diabetes & metabolism, ACS - Pulmonary hypertension & thrombosis, and ACS - Microcirculation
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Registry ,Critical Illness ,India ,Critical Care and Intensive Care Medicine ,Community Networks ,Nepal ,Development economics ,Humans ,Medicine ,Pakistan ,Cooperative Behavior ,Quality improvement ,Developing Countries ,Bangladesh ,Low- and middle-income countries ,business.industry ,Critically ill ,lcsh:Medical emergencies. Critical care. Intensive care. First aid ,Afghanistan ,Malaysia ,lcsh:RC86-88.9 ,Thailand ,Critical care ,Editorial ,Vietnam ,Laos ,Low and middle income countries ,business - Published
- 2020
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32. Loss of ULK1 Attenuates Cholesterogenic Gene Expression in Mammalian Hepatic Cells
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Sangam Rajak, Liliana F. Iannucci, Jin Zhou, B. Anjum, Nelson George, Brijesh K. Singh, Sujoy Ghosh, Paul M. Yen, and Rohit A. Sinha
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0301 basic medicine ,FOXO3A transcription factor ,cholesterogenesis ,Autophagy ,mevalonate pathway ,Cell Biology ,ULK1 ,SREBF2 ,Article ,Cell biology ,Transcriptome ,03 medical and health sciences ,Metabolic pathway ,030104 developmental biology ,0302 clinical medicine ,lcsh:Biology (General) ,030220 oncology & carcinogenesis ,Gene expression ,Hepatic stellate cell ,Gene silencing ,Mevalonate pathway ,lcsh:QH301-705.5 ,Developmental Biology - Abstract
The hepatic mevalonate (MVA) pathway, responsible for cholesterol biosynthesis, is a therapeutically important metabolic pathway in clinical medicine. Using an unbiased transcriptomics approach, we uncover a novel role of Unc-51 like autophagy activating kinase 1 (ULK1) in regulating the expression of the hepatic de novo cholesterol biosynthesis/MVA pathway genes. Genetic silencing of ULK1 in non-starved mouse (AML-12) and human (HepG2) hepatic cells as well as in mouse liver followed by transcriptome and pathway analysis revealed that the loss of ULK1 expression led to significant down-regulation of genes involved in the MVA/cholesterol biosynthesis pathway. At a mechanistic level, loss of ULK1 led to decreased expression of SREBF2/SREBP2 (sterol regulatory element binding factor 2) via its effects on AKT-FOXO3a signaling and repression of SREBF2 target genes in the MVA pathway. Our findings, therefore, discover ULK1 as a novel regulator of cholesterol biosynthesis and a possible druggable target for controlling cholesterol-associated pathologies.
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- 2020
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33. Multiple Site Cryoablation Treatment of the Posterior Nasal Nerve for Treatment of Chronic Rhinitis: An Observational Feasibility Study
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Ellen M O'Malley, David M Yen, David B. Conley, Tracy A Byerly, and Jacob Johnson
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lcsh:Immunologic diseases. Allergy ,medicine.medical_specialty ,Meatus ,medicine.medical_treatment ,Cryotherapy ,03 medical and health sciences ,0302 clinical medicine ,Nonallergic rhinitis ,medicine ,otorhinolaryngologic diseases ,Immunology and Allergy ,Multiple site ,030223 otorhinolaryngology ,allergic rhinitis ,business.industry ,nonallergic rhinitis ,Chronic rhinitis ,Cryoablation ,Nasal Nerve ,medicine.disease ,lcsh:Otorhinolaryngology ,Clinical Trial ,lcsh:RF1-547 ,Surgery ,Otorhinolaryngology ,030220 oncology & carcinogenesis ,posterior nasal nerve ,symptoms ,Observational study ,business ,lcsh:RC581-607 ,cryotherapy ,feasibility - Abstract
Background Cryoablation of the posterior nasal nerve at the middle meatus has been shown to successfully treat nasal obstruction and symptoms of chronic rhinitis. Cryoablation of both the middle and inferior meatus has not yet been studied. Objectives To evaluate the safety and feasibility of cryoablation of the posterior nasal nerve at both the middle and inferior meatus locations to treat chronic rhinitis. Methods Participants underwent bilateral cryoablation of the posterior nasal nerve at both the middle meatus and inferior meatus and were assessed through 3 months post treatment. The primary endpoint is the change from baseline to 3-month follow-up in the reflective Total Nasal Symptom Score (rTNSS). Other assessments include additional patient-reported outcomes, physician assessment, and independent review and scoring of imaging. Results Thirty participants were enrolled at 3 US centers. There was a significant improvement from baseline in the median rTNSS (–4.0, P Conclusion Cryoablation at both the middle meatus and inferior meatus appears to be a safe and feasible option for treatment of chronic rhinitis. In this feasibility study, there is significant improvement in symptoms post treatment. Adverse events are minor and transient.
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- 2020
34. In Response to Letter to the Editor Regarding In-Office Tympanostomy Tube Placement in Children Using Iontophoresis and Automated Tube Delivery
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Robert C. Sprecher, Amy Brenski, Robert Puchalski, Ritvik P. Mehta, Charles A. Syms, Scott R. Schoem, Andrew R. Gould, Jacob W. Zeiders, Susannah Hills, Eli Grunstein, David M. Brown, Erik H. Waldman, Christopher York, Dan Harfe, John Gavin, Audrey P. Calzada, Amy Ingram, Michael T. Murray, Frederick K. Kozak, Lawrence R. Lustig, Neil K. Chadha, D. Macy Vidrine, Christopher R. Thompson, Denise A. Sherman, John Ansley, David M. Yen, John E. McClay, Laura J. England, Randall A. Ow, and Jonathan R. Moss
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medicine.medical_specialty ,Letter to the editor ,Iontophoresis ,Middle ear ventilation ,business.industry ,medicine.medical_treatment ,Middle Ear Ventilation ,Surgery ,Otorhinolaryngology ,medicine ,Humans ,Tube (fluid conveyance) ,Tympanostomy tube ,business ,Child - Published
- 2020
35. The real demonstration of High-Quality Carbon Nano-Tubes (CNTs) as the electrical connection for the potential application in a vertical 3D integrated technology
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H. T. Hung, Y.-R. Li, C. R. Kao, C.-C. A. Chen, Min-Hung Lee, C.-M. Yen, Min-Sheng Liao, P.-Y. Lu, and W.-C. Pu
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010302 applied physics ,010407 polymers ,Materials science ,business.industry ,Integrated circuit ,Chemical vapor deposition ,01 natural sciences ,Thermal expansion ,Electrical connection ,0104 chemical sciences ,law.invention ,Thermal conductivity ,Residual stress ,law ,0103 physical sciences ,Nano ,Optoelectronics ,business ,Material properties - Abstract
High-quality and the large area Carbon Nano-Tube (CNTs) is grown by Chemical Vapor Deposition (CVD) method in different trench structures for the potential applications on the vertically three-dimension integrated circuits (3DICs). It’s unique material properties, including Resistivity (p), thermal conductivity (k), coefficient of thermal expansion (CTE), and Young’s modulus (E) make it viable for the potential applications in the monolithic 3D vertically integrated technologies. Besides the well-known lower p in CNTs for the easier electron carrier transport, the higher k-value in CNTs— which is ~4500 Wm-1K-1 and 10x higher than Cu— results in the better thermal dissipation (~I5°C reduction) for the reduction of self-heating effect in the high dense 3D devices. On the other hand, the near-zero/negative CTE of -2xlO-6 K-1 and ultra-high E-value of 1000 GPa in CNTs is also found to reduce the residual stress and furtherly enhance the acceptable device layout area (by 80% keep-out zone reduction) in the 3D vertically integrated devices significantly. The prototype and full process flow for the CNTs as the vertical connection material for the 3D integrated technologies is demonstrated successfully. In summary, the growth of high-quality CNTs in the trench structure with a good electrical and mechanical material properties, and the development of an advanced key- module process for the monolithic 3D vertically integrated technologies provide a useful solution for the future high- performance and high-dense 3D integrated devices.
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- 2020
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36. Thermogenesis in Adipose Tissue Activated by Thyroid Hormone
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Paul M. Yen and Winifred W. Yau
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0301 basic medicine ,Thyroid Hormones ,medicine.medical_specialty ,Sympathetic nervous system ,Adipose Tissue, White ,Adipose tissue ,030209 endocrinology & metabolism ,Review ,White adipose tissue ,Catalysis ,Inorganic Chemistry ,lcsh:Chemistry ,03 medical and health sciences ,0302 clinical medicine ,Adipose Tissue, Brown ,Internal medicine ,Brown adipose tissue ,medicine ,Animals ,Humans ,Uncoupling protein ,Physical and Theoretical Chemistry ,Molecular Biology ,lcsh:QH301-705.5 ,Spectroscopy ,browning ,Chemistry ,Organic Chemistry ,brown adipose tissue ,General Medicine ,thermogenesis ,Adipose Tissue, Beige ,Thermoregulation ,thyroid hormone ,Mitochondria ,Computer Science Applications ,Glucose ,030104 developmental biology ,Endocrinology ,medicine.anatomical_structure ,Adipose Tissue ,lcsh:Biology (General) ,lcsh:QD1-999 ,Shivering ,medicine.symptom ,Energy Metabolism ,Oxidation-Reduction ,Thermogenesis - Abstract
Thermogenesis is the production of heat that occurs in all warm-blooded animals. During cold exposure, there is obligatory thermogenesis derived from body metabolism as well as adaptive thermogenesis through shivering and non-shivering mechanisms. The latter mainly occurs in brown adipose tissue (BAT) and muscle; however, white adipose tissue (WAT) also can undergo browning via adrenergic stimulation to acquire thermogenic potential. Thyroid hormone (TH) also exerts profound effects on thermoregulation, as decreased body temperature and increased body temperature occur during hypothyroidism and hyperthyroidism, respectively. We have termed the TH-mediated thermogenesis under thermoneutral conditions “activated” thermogenesis. TH acts on the brown and/or white adipose tissues to induce uncoupled respiration through the induction of the uncoupling protein (Ucp1) to generate heat. TH acts centrally to activate the BAT and browning through the sympathetic nervous system. However, recent studies also show that TH acts peripherally on the BAT to directly stimulate Ucp1 expression and thermogenesis through an autophagy-dependent mechanism. Additionally, THs can exert Ucp1-independent effects on thermogenesis, most likely through activation of exothermic metabolic pathways. This review summarizes thermogenic effects of THs on adipose tissues.
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- 2020
37. Development of an in vitro senescent hepatic cell model for metabolic studies in aging
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Paul M. Yen, Brijesh K. Singh, Madhulika Tripathi, Keziah Tikno, Jin Zhou, and Reddima Sandireddy
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Glutamine ,Senescence ,medicine.anatomical_structure ,Cell culture ,Hepatocyte ,medicine ,Hepatic stellate cell ,Glycolysis ,Biology ,medicine.disease_cause ,In vitro ,Oxidative stress ,Cell biology - Abstract
Although aging in the liver contributes to the development of chronic liver diseases such as NAFLD and insulin resistance, little known about the molecular and metabolic details of aging in hepatic cells. To examine these issues, we used sequential oxidative stress with hydrogen peroxide to induce premature senescence in AML12 hepatic cells. The senescent cells exhibited molecular and metabolic signatures, increased SA-βGal and γH2A.X staining, and elevated senescence and pro-inflammatory gene expression that resembled livers from aged mice. Metabolic phenotyping showed fuel switching towards glycolysis and mitochondrial glutamine oxidation as well as impaired energy production. The senescent AML12 cells also had increased mTOR signaling and decreased autophagy which likely contributed to the fuel switching from β-oxidation that occurred in normal AML12 cells. Additionally, senescence activated secretory proteins from conditioned media of senescent cells sensitized normal AML12 cells to palmitate-induced toxicity, a known pathological effect of hepatic aging. In summary, we have generated senescent AML12 cells which displayed the molecular hallmarks of aging, and also exhibited the aberrant metabolic phenotype, mitochondrial function, and cell signaling that occur in the aged liver.
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- 2020
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38. Profiling retrospective thyroid function data in complete thyroidectomy patients to investigate the HPT axis set point (PREDICT-IT)
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E, Li, P M, Yen, J W, Dietrich, and M K-S, Leow
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Male ,Hypothalamo-Hypophyseal System ,Hormone Replacement Therapy ,Thyroid Gland ,Thyrotropin ,Middle Aged ,Thyroid Function Tests ,Thyroid Diseases ,Thyroxine ,Reference Values ,Thyroidectomy ,Humans ,Drug Dosage Calculations ,Female ,Postoperative Period ,Thyrotropin-Releasing Hormone ,Algorithms - Abstract
The homeostatic euthyroid set point of the hypothalamus-pituitary-thyroid axis of any given individual is unique and oscillates narrowly within substantially broader normal population ranges of circulating free thyroxine (FT4) and thyroid-stimulating hormone (TSH), otherwise termed 'thyroid function test (TFT)'. We developed a mathematical algorithm codenamed Thyroid-SPOT that effectively reconstructs the personalized set point in open-loop situations and evaluated its performance in a retrospective patient sample.We computed the set points of 101 patients who underwent total thyroidectomy for non-functioning thyroid disease using Thyroid-SPOT on each patient's own serial post-thyroidectomy TFT. Every predicted set point was compared against its respective healthy pre-operative euthyroid TFT per individual and their separation (i.e. predicted-observed TFT) quantified.Bland-Altman analysis to measure the agreement between each pair of an individual's predicted and actual set points revealed a mean difference in FT4 and TSH of + 3.03 pmol/L (95% CI 2.64, 3.43) and - 0.03 mIU/L (95% CI - 0.25, 0.19), respectively. These differences are small compared to the width of the reference intervals. Thyroid-SPOT can predict the euthyroid set point remarkably well, especially for TSH with a 10-16-fold spread in magnitude between population normal limits.Every individual's equilibrium euthyroid set point is unique. Thyroid-SPOT serves as an accurate, precise and reliable targeting system for optimal personalized restoration of euthyroidism. This algorithm can guide clinicians in L-thyroxine dose titrations to resolve persistent dysthyroid symptoms among challenging cases harbouring "normal TFT" within the laboratory ranges but differing significantly from their actual euthyroid set points.
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- 2020
39. Autocrine IL11 cis-signaling in hepatocytes is an initiating nexus between lipotoxicity and non-alcoholic steatohepatitis
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Jinrui Dong, Brijesh K. Singh, Sze-Yun Lim, Benjamin Ng, Shamini Guna Shekeran, Jin Zhou, Nicole S. J. Ko, Sonia Chothani, Stuart A. Cook, Tan J, Sebastian Schafer, W. Lim, Pei Min Lio, Anissa A. Widjaja, Paul M. Yen, Eleonora Adami, Sivakumar Viswanathan, and Mao Wang
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medicine.medical_specialty ,Chemistry ,Fatty liver ,Inflammation ,medicine.disease ,medicine.anatomical_structure ,Endocrinology ,Lipotoxicity ,Fibrosis ,Hepatocyte ,Internal medicine ,medicine ,Steatosis ,Steatohepatitis ,medicine.symptom ,Autocrine signalling - Abstract
Background and aimsIL11 signaling is important in non-alcoholic steatohepatitis (NASH) but how it contributes to NASH pathologies beyond fibrosis is not known. Here we investigate the role of IL11 signaling in hepatocyte lipotoxicity.MethodsHepatocytes were stimulated with IL6, IL11, HyperIL6, or HyperIL11 alone or in the presence of soluble gp130 (sgp130) or soluble IL11RA (sIL11RA), or loaded with palmitate in the presence of IgG or anti-IL11RA (X209) antibodies or sgp130. Effects were assessed using colorimetric ALT, GSH, or ELISA assays, immunoblots, and flow cytometry. The relative contributions of IL11 cis-versus -trans signaling in vivo was assessed in two preclinical NASH models using a high fat methionine/choline deficient diet or a Western diet with liquid fructose in C57BL6/Ntac mice injected with AAV8-Alb-Cre, AAV8-Alb-sgp130, in mice with hepatocyte-specific deletion of Il11ra (CKO), and in mice with global deletion of Il11ra injected with AAV8-Alb-mIl11ra or AAV8-Alb-sIl11ra. Livers and serum were collected; serum samples were analyzed using biochemistry and liver tissues were analyzed by histology, qPCR, immunobloting, hydroxyproline, and GSH assays.ResultsWe show that lipid-laden hepatocytes secrete IL11, which acts via autocrine cis-signaling to cause lipoapoptosis. IL11 causes lipotoxic hepatocyte death through activation of non-canonical signaling pathways and increased NOX4-derived reactive oxygen species. In two preclinical models, hepatocyte-specific deletion of Il11ra1 protects mice from all aspects of NASH with beneficial effects on body weight. In accordance, restoration of IL11 cis-signaling in hepatocytes only in mice globally deleted for Il11ra1 reconstitutes steatosis and inflammation. Throughout, we found no evidence to support the existence of IL6 or IL11 trans-signaling in the liver.ConclusionWe conclude that autocrine IL11-mediated cell death underlies hepatocyte lipotoxicity and that liver fibrosis and inflammation occur subsequently. These data highlight a new disease mechanism for the transition from compensated fatty liver disease to NASH.
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- 2020
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40. Estrogen-Related Receptor Alpha: An Under-Appreciated Potential Target for the Treatment of Metabolic Diseases
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Paul M. Yen, Madhulika Tripathi, and Brijesh K. Singh
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0301 basic medicine ,Mitochondrial Turnover ,estrogen-related receptor alpha ,adaptive thermogenesis ,Review ,Biology ,mitochondrial turnover ,metabolic diseases ,Catalysis ,adipogenesis ,Inorganic Chemistry ,lcsh:Chemistry ,03 medical and health sciences ,Estrogen-related receptor alpha ,0302 clinical medicine ,Mitophagy ,Animals ,Humans ,Molecular Targeted Therapy ,Physical and Theoretical Chemistry ,Receptor ,Molecular Biology ,Gene ,lcsh:QH301-705.5 ,Spectroscopy ,Organic Chemistry ,Autophagy ,General Medicine ,Computer Science Applications ,030104 developmental biology ,mitophagy ,Nuclear receptor ,lcsh:Biology (General) ,lcsh:QD1-999 ,Receptors, Estrogen ,Adipogenesis ,030220 oncology & carcinogenesis ,Cancer research ,Energy Metabolism ,Oxidation-Reduction ,non-alcoholic fatty liver disease (NAFLD) - Abstract
The estrogen-related receptor alpha (ESRRA) is an orphan nuclear receptor (NR) that significantly influences cellular metabolism. ESRRA is predominantly expressed in metabolically-active tissues and regulates the transcription of metabolic genes, including those involved in mitochondrial turnover and autophagy. Although ESRRA activity is well-characterized in several types of cancer, recent reports suggest that it also has an important role in metabolic diseases. This minireview focuses on the regulation of cellular metabolism and function by ESRRA and its potential as a target for the treatment of metabolic disorders.
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- 2020
41. PD-linked CHCHD2 mutations impair CHCHD10 and MICOS complex leading to mitochondria dysfunction
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Paul M. Yen, Brijesh K. Singh, Eyleen L. K. Goh, Danlei Wang, Jin Zhou, Dongrui Ma, Jinyan Zhang, Yi Zhao, Eng-King Tan, Dongliang Ma, Hoang-Dai Tran, Alfred Xuyang Sun, and Wei Zhou
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Male ,0301 basic medicine ,Mitochondrial Diseases ,Human Embryonic Stem Cells ,Oxidative phosphorylation ,Mitochondrion ,Biology ,medicine.disease_cause ,Cell Line ,Mitochondrial Proteins ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Genetics ,medicine ,Animals ,Humans ,CRISPR ,Molecular Biology ,Genetic Association Studies ,Genetics (clinical) ,Gene knockdown ,Mutation ,MICOS complex ,Neurodegenerative Diseases ,Parkinson Disease ,General Medicine ,Elamipretide ,Neural stem cell ,Mitochondria ,Cell biology ,DNA-Binding Proteins ,Mice, Inbred C57BL ,030104 developmental biology ,Frontotemporal Dementia ,Mitochondrial Membranes ,General Article ,Oligopeptides ,030217 neurology & neurosurgery ,Transcription Factors - Abstract
Coiled-coil-helix-coiled-coil-helix domain containing protein 2 (CHCHD2) mutations were linked with autosomal dominant Parkinson’s disease (PD) and recently, Alzheimer’s disease/frontotemporal dementia. In the current study, we generated isogenic human embryonic stem cell (hESC) lines harboring PD-associated CHCHD2 mutation R145Q or Q126X via clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9) method, aiming to unravel pathophysiologic mechanism and seek potential intervention strategy against CHCHD2 mutant-caused defects. By engaging super-resolution microscopy, we identified a physical proximity and similar distribution pattern of CHCHD2 along mitochondria with mitochondrial contact site and cristae organizing system (MICOS), a large protein complex maintaining mitochondria cristae. Isogenic hESCs and differentiated neural progenitor cells (NPCs) harboring CHCHD2 R145Q or Q126X mutation showed impaired mitochondria function, reduced CHCHD2 and MICOS components and exhibited nearly hollow mitochondria with reduced cristae. Furthermore, PD-linked CHCHD2 mutations lost their interaction with coiled-coil-helix-coiled-coil-helix domain containing protein 10 (CHCHD10), while transient knockdown of either CHCHD2 or CHCHD10 reduced MICOS and mitochondria cristae. Importantly, a specific mitochondria-targeted peptide, Elamipretide/MTP-131, now tested in phase 3 clinical trials for mitochondrial diseases, was found to enhance CHCHD2 with MICOS and mitochondria oxidative phosphorylation enzymes in isogenic NPCs harboring heterozygous R145Q, suggesting that Elamipretide is able to attenuate CHCHD2 R145Q-induced mitochondria dysfunction. Taken together, our results suggested CHCHD2–CHCHD10 complex may be a novel therapeutic target for PD and related neurodegenerative disorders, and Elamipretide may benefit CHCHD2 mutation-linked PD.
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- 2018
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42. Bezafibrate induces autophagy and improves hepatic lipid metabolism in glycogen storage disease type Ia
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Dwight D. Koeberl, Tsubasa Kudo, Stuart A. Grant, Yajun Wu, Elizabeth D. Brooks, Bay Boon Huat, Paul M. Yen, Lauren R Waskowicz, Zollie A Yavarow, Sarah P. Young, Dustin J. Landau, Haoyue Zhang, Jin Zhou, and Andrea Lim
- Subjects
medicine.medical_specialty ,Glucose-6-Phosphate ,Glycogen Storage Disease Type I ,Biology ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,Dogs ,Internal medicine ,Autophagy ,Genetics ,medicine ,Animals ,Molecular Biology ,Beta oxidation ,Triglycerides ,Genetics (clinical) ,Mice, Knockout ,0303 health sciences ,Glycogen storage disease type I ,Bezafibrate ,Triglyceride ,Glycogen ,030305 genetics & heredity ,Fatty liver ,General Medicine ,Lipid Metabolism ,medicine.disease ,Disease Models, Animal ,Fatty acid synthase ,Glucose ,Endocrinology ,Liver ,chemistry ,Lipogenesis ,Glucose-6-Phosphatase ,biology.protein ,General Article ,medicine.drug - Abstract
Glucose-6-phosphatase α (G6Pase) deficiency, also known as von Gierke’s Disease or Glycogen storage disease type Ia (GSD Ia), is characterized by decreased ability of the liver to convert glucose-6-phosphate to glucose leading to glycogen accumulation and hepatosteatosis. Long-term complications of GSD Ia include hepatic adenomas and carcinomas, in association with the suppression of autophagy in the liver. The G6pc−/− mouse and canine models for GSD Ia were treated with the pan-peroxisomal proliferator-activated receptor agonist, bezafibrate, to determine the drug’s effect on liver metabolism and function. Hepatic glycogen and triglyceride concentrations were measured and western blotting was performed to investigate pathways affected by the treatment. Bezafibrate decreased liver triglyceride and glycogen concentrations and partially reversed the autophagy defect previously demonstrated in GSD Ia models. Changes in medium-chain acyl-CoA dehydrogenase expression and acylcarnintine flux suggested that fatty acid oxidation was increased and fatty acid synthase expression associated with lipogenesis was decreased in G6pc−/− mice treated with bezafibrate. In summary, bezafibrate induced autophagy in the liver while increasing fatty acid oxidation and decreasing lipogenesis in G6pc−/− mice. It represents a potential therapy for glycogen overload and hepatosteatosis associated with GSD Ia, with beneficial effects that have implications for non-alcoholic fatty liver disease.
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- 2018
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43. Thyroid hormone (T3) stimulates brown adipose tissue activation via mitochondrial biogenesis and MTOR-mediated mitophagy
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Lei Sun, Ronny Lesmana, Yajun Wu, Boon-Huat Bay, Winifred W. Yau, Brijesh K. Singh, Rohit A. Sinha, Jin Zhou, Shigeki Sugii, Paul M. Yen, and Kiraely Adam Wong
- Subjects
0301 basic medicine ,Triiodothyronine ,030102 biochemistry & molecular biology ,ATP synthase ,Autophagy ,food and beverages ,Cell Biology ,Mitochondrion ,Biology ,Cell biology ,03 medical and health sciences ,030104 developmental biology ,medicine.anatomical_structure ,Mitochondrial biogenesis ,Brown adipose tissue ,Mitophagy ,medicine ,biology.protein ,Molecular Biology ,Thermogenesis - Abstract
The thyroid hormone triiodothyronine (T3) activates thermogenesis by uncoupling electron transport from ATP synthesis in brown adipose tissue (BAT) mitochondria. Although T3 can induce thermogenesi...
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- 2018
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44. Low-Dose Levothyroxine Reduces Intrahepatic Lipid Content in Patients With Type 2 Diabetes Mellitus and NAFLD
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Suresh Anand Sadananthan, Kurumbian Chandran, Rohit A. Sinha, Navin Michael, Li Wei Cho, Eng Kiong Teo, Louise M Burrell, Peter W Angus, Christopher Leung, Chee Fang Sum, Eveline Bruinstroop, Su Chi Lim, Sheila K Patel, Heather M. Stapleton, Melvin Khee-Shing Leow, Yang Cao, S. Sendhil Velan, Paul M. Yen, Shui Boon Soh, Yong Mong Bee, Rinkoo Dalan, and Sue-Anne Toh
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Adult ,Male ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Levothyroxine ,030209 endocrinology & metabolism ,Biochemistry ,Gastroenterology ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,Insulin resistance ,Non-alcoholic Fatty Liver Disease ,Diabetes mellitus ,Internal medicine ,Nonalcoholic fatty liver disease ,medicine ,Humans ,Euthyroid ,medicine.diagnostic_test ,business.industry ,Biochemistry (medical) ,Middle Aged ,medicine.disease ,Lipids ,Thyroxine ,Treatment Outcome ,Diabetes Mellitus, Type 2 ,Liver ,030211 gastroenterology & hepatology ,Steatosis ,Thyroid function ,Lipid profile ,business ,medicine.drug - Abstract
Context Nonalcoholic fatty liver disease (NAFLD) is highly prevalent in patients with type 2 diabetes mellitus (T2DM) and associated with significant morbidity and mortality. Thyroid hormone (TH) increases β-oxidation of fatty acids and decreases intrahepatic lipid content (IHLC) in rodents with NAFLD. Objective We investigated the possibility of low intrahepatic TH concentration in NAFLD and studied the effect of TH treatment in humans. Design/setting This was a phase 2b single-arm study in six hospitals in Singapore. Intrahepatic thyroid hormone concentrations were measured in rats with induced NAFLD. Patients Euthyroid patients with T2DM and steatosis measured by ultrasonography. Intervention Levothyroxine was titrated to reach a thyroid-stimulating hormone level of 0.34 to 1.70 mIU/L before a 16-week maintenance phase. Main outcome measures The primary outcome measure was change in IHLC measured by proton magnetic resonance spectroscopy after treatment. Results Twenty male patients were included in the per-protocol analysis [mean ± SD: age, 47.8 ± 7.8 years; body mass index (BMI), 30.9 ± 4.4 kg/m2; baseline IHLC, 13% ± 4%]. After treatment, IHLC was decreased 12% (±SEM, 26%) relative to baseline (absolute change, -2%; 95% CI, -3 to 0; P = 0.046). Small decreases in BMI (P = 0.044), visceral adipose tissue volume (P = 0.047), and subcutaneous adipose tissue volume (P = 0.045) were observed. No significant changes in glucose regulation or lipid profile occurred. Conclusion This study demonstrated the efficacy and safety of low-dose TH therapy for NAFLD in men. TH or TH analogs may be beneficial for this condition.
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- 2018
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45. MTORC1 inhibition drives crinophagic degradation of glucagon
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Rohit A. Sinha, Yajun Wu, Sana Raza, Boon-Huat Bay, Archana Tewari, Sangam Rajak, Sherwin Xie, and Paul M. Yen
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Male ,Mice, Transgenic ,Enteroendocrine cell ,mTORC1 ,Mechanistic Target of Rapamycin Complex 1 ,Brief Communication ,Glucagon ,Mice ,Autophagy ,medicine ,Animals ,Secretion ,Rapamycin ,Internal medicine ,Molecular Biology ,Cells, Cultured ,MTORC1 ,Chemistry ,Secretory Vesicles ,Diabetes ,Glucagon secretion ,Cell Biology ,RC31-1245 ,Cell biology ,Mice, Inbred C57BL ,Crinophagy ,Mechanism of action ,medicine.symptom ,Lysosomes ,Intracellular - Abstract
Objective Crinophagy is a secretory granule-specific autophagic process that regulates hormone content and secretion in endocrine cells. However, despite being one of the earliest described autophagic processes, its mechanism of action and regulation in mammalian cells remains unclear. Methods and results Here, we examined mammalian crinophagy and its modulation that regulate hormone secretion in a glucagon-producing mouse pancreatic α-cell line, alpha TC1 clone 9 (αTC9), and in vivo. Western blot, electron microscopy, and immunofluorescence analyses were performed to study crinophagy and glucagon secretion in αTC9 cells and C57BL/6 mice, in response to the mammalian target of rapamycin complex 1 (MTORC1) inhibitor rapamycin. Amino acid depletion and pharmacological inhibition of MTORC1 increased the shuttling of glucagon-containing secretory granules into lysosomes for crinophagic degradation to reduce glucagon secretion through a macroautophagy-independent mechanism. Furthermore, MTORC1 inhibition reduced both intracellular and secreted glucagon in rapamycin-treated mice, in response to hypoglycaemia. Conclusion In summary, we have identified a novel crinophagic mechanism of intracellular glucagon turnover in pancreatic α-cells regulated by MTORC1 signalling., Graphical abstract Image 1, Highlights • Crinophagy regulates α-cell glucagon levels. • MTORC1 inhibition induces glucagon crinophagy. • Glucagon crinophagy is macroautophagy-independent.
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- 2021
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46. A phase 3 trial of mometasone furoate sinus implants for chronic sinusitis with recurrent nasal polyps
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Anna K. Gawlicka, Langford Fpj, Robert C. Kern, Ameet Singh, Boris Karanfilov, Iloreta Amc, Silvers Sl, James W. Stambaugh, Keith E. Matheny, Stolovitzky Jp, David M Yen, and Lee Jt
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medicine.medical_specialty ,business.industry ,Standard treatment ,Mometasone furoate ,medicine.disease ,Surgery ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,030228 respiratory system ,Otorhinolaryngology ,Ethmoid sinus ,otorhinolaryngologic diseases ,medicine ,Immunology and Allergy ,Nasal polyps ,Nasal administration ,Implant ,030223 otorhinolaryngology ,Adverse effect ,business ,Sinus (anatomy) ,medicine.drug - Abstract
Background Topical intranasal corticosteroid sprays (INCSs) are standard treatment for nasal polyps (NPs), but their efficacy is reduced by poor patient compliance and impaired access of drug to the sinus mucosa. A corticosteroid-eluting sinus implant was designed to address these limitations in patients with recurrent polyposis after sinus surgery by delivering 1350 μg of mometasone furoate (MF) directly to the ethmoid sinus mucosa over approximately 90 days. Methods A randomized, sham-controlled, double-blind trial was undertaken in 300 adults with refractory chronic rhinosinusitis with NPs (CRSwNP), who were candidates for repeat surgery. Eligible patients were randomized (2:1) and underwent in-office bilateral placement of 2 implants or a sham procedure. All patients used the MF INCS 200 μg once daily. Co-primary efficacy endpoints were the change from baseline in nasal obstruction/congestion score and bilateral polyp grade, as determined by an independent panel based on centralized, blinded videoendoscopy review. Results Patients treated with implants experienced significant reductions in both nasal obstruction/congestion score (p = 0.0074) and bilateral polyp grade (p = 0.0073) compared to controls. At day 90, implants were also associated with significant reductions in 4 of 5 prespecified secondary endpoints compared to control: proportion of patients still indicated for repeat sinus surgery (p = 0.0004), percent ethmoid sinus obstruction (p = 0.0007), nasal obstruction/congestion (p = 0.0248), and decreased sense of smell (p = 0.0470), but not facial pain/pressure (p = 0.9130). One patient experienced an implant-related serious adverse event (epistaxis). Conclusion Significant improvements over a range of subjective and objective endpoints, including a reduction in the need for sinus surgery by 61%, suggest that MF sinus implants may play an important role in management of recurrent NP.
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- 2018
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47. Impact of atrial fibrillation in patients with chronic kidney disease undergoing transcatheter aortic valve replacement: Insights of the Healthcare Cost and Utilization Project's National Inpatient Sample
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Tzyy Yun M. Yen, Alice Cheung, Javed Butler, Fabio V. Lima, Luis Gruberg, and Puja B. Parikh
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Male ,medicine.medical_specialty ,Time Factors ,Databases, Factual ,medicine.medical_treatment ,Clinical Decision-Making ,Heart Valve Diseases ,030204 cardiovascular system & hematology ,Kidney ,urologic and male genital diseases ,Logistic regression ,Risk Assessment ,End stage renal disease ,Transcatheter Aortic Valve Replacement ,03 medical and health sciences ,Postoperative Complications ,0302 clinical medicine ,Valve replacement ,Risk Factors ,Internal medicine ,Atrial Fibrillation ,medicine ,Humans ,030212 general & internal medicine ,Renal Insufficiency, Chronic ,Stage (cooking) ,Adverse effect ,Healthcare Cost and Utilization Project ,Aged ,Retrospective Studies ,Aged, 80 and over ,business.industry ,Patient Selection ,Atrial fibrillation ,General Medicine ,Length of Stay ,medicine.disease ,United States ,female genital diseases and pregnancy complications ,Treatment Outcome ,Aortic Valve ,Cardiology ,Female ,Cardiology and Cardiovascular Medicine ,business ,Kidney disease - Abstract
Background Limited data exists exploring the relationship between varying degrees of chronic kidney disease (CKD) and atrial fibrillation (AF) in patients undergoing transcatheter aortic valve replacement (TAVR). Methods Records were selected from the 2011 to 2012 Healthcare Cost and Utilization Project's National Inpatient Sample for TAVR patients with pre-existing AF and CKD. Demographics, clinical characteristics, and TAVR-related in-hospital adverse events were identified and compared between patients with and without AF and moderate CKD (CKD stage 3–4), and between patients with and without AF and severe CKD (CKD stage 5 or end stage renal disease [ESRD]). Evaluated outcomes included major adverse cardiac and cerebrovascular events (MACCE). Results We identified a total of 293 patients with moderate CKD (stage 3 and higher) that underwent TAVR at selected U.S. hospitals between 2011 and 2012. Among these patients, 112 had a diagnosis of AF and 181 did not have AF. MACCE rates were similar among CKD 3–4 patients with and without AF (10.3% and 9.0% respectively, p = 0.74). MACCE rates were similar among CKD 5/ESRD patients with and without AF (20.0% and 16.2% respectively, p = 0.74). However, MACCE rates were higher in patients with CKD 5/ESRD compared with CKD 3–4 patients. Multivariate logistic regression analysis did not show that AF was an independent predictor of in-hospital MACCE. Conclusions In a large retrospective analysis of CKD stage 3–4 or CKD 5/ESRD patients undergoing TAVR at selected U.S. hospitals, the presence of AF did not seem to be associated with increased adverse in-hospital events or length of stay.
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- 2018
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48. A fluorescent methylation-switchable probe for highly sensitive analysis of FTON6-methyladenosine demethylase activity in cells
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Paul M. Yen, Joanne J. A. Low, Andrea Lim, Esther C. Y. Woon, and Adeline Cheong
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0301 basic medicine ,Messenger RNA ,medicine.diagnostic_test ,Chemistry ,RNA ,General Chemistry ,Computational biology ,Methylation ,In vitro ,Flow cytometry ,03 medical and health sciences ,030104 developmental biology ,Demethylase activity ,medicine ,Epigenetics ,Oligomer restriction - Abstract
N 6-Methyladenosine (m6A) is one of the most abundant epigenetic modifications on mRNA. It is dynamically regulated by the m6A demethylases FTO and ALKBH5, which are currently attracting intense medical interest because of their strong association with several human diseases. Despite their clinical significance, the molecular mechanisms of m6A demethylases remain unclear, hence there is tremendous interest in developing analytical tools to facilitate their functional studies, with a longer term view of validating their therapeutic potentials. To date, no method exists which permits the analysis of m6A-demethylase activity in cells. To overcome this challenge, herein, we describe the first example of a fluorescent m6A-switchable oligonucleotide probe, which enables the direct detection of FTO demethylase activity both in vitro and in living cells. The m6A probe provides a simple, yet powerful visual tool for highly sensitive detection of demethylase activity. Through the use of m6A-probe, we were able to achieve real-time imaging and single-cell flow cytometry analyses of FTO activity in HepG2 cells. We also successfully applied the probe to monitor dynamic changes in FTO activity and m6A methylation levels during 3T3-L1 pre-adipocyte differentiation. The strategy outlined here is highly versatile and may, in principle, be adapted to the study of a range of RNA demethylases and, more widely, other RNA modifying enzymes. To the best of our knowledge, the present study represents not only the first assay for monitoring FTO activity in living cells, but also a new strategy for sensing m6A methylation dynamics.
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- 2018
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49. Role of thyroid hormone in hepatic gene regulation, chromatin remodeling, and autophagy
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Rohit A. Sinha, Paul M. Yen, Brijesh K. Singh, and Kenji Ohba
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Transcriptional Activation ,0301 basic medicine ,Gene isoform ,Thyroid Hormones ,Biology ,Biochemistry ,Chromatin remodeling ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,Autophagy ,Animals ,Humans ,Epigenetics ,Molecular Biology ,Transcription factor ,Regulation of gene expression ,Receptors, Thyroid Hormone ,Thyroid hormone receptor ,Chromatin Assembly and Disassembly ,Mitochondria ,030104 developmental biology ,Liver ,030220 oncology & carcinogenesis ,Cancer research ,Transcription Factors ,Hormone - Abstract
Thyroid hormone (TH) actions on development and metabolism have been studied ever since the discovery of thyroxine almost a century ago. Initial studies focused on the physiological and biochemical actions of TH. Later, the cloning of the thyroid hormone receptor (THR) isoforms and the development of techniques enabled the study of TH regulation of complex cellular processes (such as gene transcription). Recently we found that TH activates secondary transcription factors such as FOXO1, to amplify gene transcription; and also is a potent inducer of autophagy that was critical for fatty acid β-oxidation in the liver. This review summarizes the recent advancements in our understanding of TH regulation of gene expression of metabolic genes (via co-regulators/transcription factors and epigenetic control) and autophagy in the liver. Our deeper understanding of TH action recently has led to the development of tissue- and THR isoform-specific TH mimetics that may be useful for the treatment of metabolic disorders.
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- 2017
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50. Renal endoplasmic reticulum stress is coupled to impaired autophagy in a mouse model of GSD Ia
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Dustin J. Landau, Yajun Wu, Rohit A. Sinha, Benjamin L. Farah, Dwight D. Koeberl, Boon-Huat Bay, Alwin Hwai Liang Loh, and Paul M. Yen
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0301 basic medicine ,congenital, hereditary, and neonatal diseases and abnormalities ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,Down-Regulation ,Glucose-6-Phosphate ,Disease ,Glycogen Storage Disease Type I ,Biology ,Kidney ,Biochemistry ,Article ,Pathogenesis ,Mice ,03 medical and health sciences ,Endocrinology ,Internal medicine ,Autophagy ,Genetics ,medicine ,Animals ,Molecular Biology ,Sirolimus ,Endoplasmic reticulum ,Fatty liver ,Genetic disorder ,nutritional and metabolic diseases ,Endoplasmic Reticulum Stress ,medicine.disease ,Disease Models, Animal ,030104 developmental biology ,Renal pathology ,Glucose-6-Phosphatase ,Unfolded protein response ,Immunosuppressive Agents - Abstract
GSD Ia (von Gierke Disease, Glycogen Storage Disease Type Ia) is a devastating genetic disorder with long-term sequelae, such as non-alcoholic fatty liver disease and renal failure. Down-regulated autophagy is involved in the development of hepatic metabolic dysfunction in GSD Ia; however, the role of autophagy in the renal pathology is unknown. Here we show that autophagy is impaired and endoplasmic reticulum (ER) stress is increased in the kidneys of a mouse model of GSD Ia. Induction of autophagy by rapamycin also reduces this ER stress. Taken together, these results show an additional role for autophagy down-regulation in the pathogenesis of GSD Ia, and provide further justification for the use of autophagy modulators in GSD Ia.
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- 2017
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