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Objective During the coronavirus disease 2019 (COVID-19) pandemic, exploring insulin resistance and β-cell activity is important for understanding COVID-19-associated new-onset diabetes. This study aimed to assess insulin sensitivity and fasting insulin secretion in COVID-19 patients without diabetes on admission and at 3 and 6 months after discharge. Methods This 6-month prospective study assessed data from the records of 64 patients without diabetes diagnosed with COVID-19 at Wenzhou Central Hospital, China. Each patient was followed up for 3 and 6 months after discharge. Repeated measures analysis of variance was used to investigate differences in multiple measurements of the same variable at different times. Linear regression analysis was performed to analyze the contributor for changes in triglyceride-glucose (TyG) index. Results Fasting C-peptide levels in patients at baseline were lower than the normal range (1.1-4.4 μg/L). Compared with baseline, patients had significantly elevated fasting C-peptide levels (0.35±0.24 vs. 2.36±0.98 vs. 2.52±1.11 μg/L, P˂0.001), HOMA-CP (0.42, IQR 0.36–0.62 vs. 2.54, IQR 1.95-3.42 vs. 2.90, IQR 2.02-4.23, P˂0.001) and TyG indexes (8.57±0.47 vs. 8.73±0.60 vs. 8.82±0.62, P=0.006), and decreased fasting glucose levels (5.84±1.21 vs. 4.95±0.76 vs. 5.40±0.68 mmol/L, P=0.003) during the 3 and 6-month follow-up. Male gender [β (95%CI): -0.312 (-0.590, -0.034)], age [0.012 (0.001, 0.023)], interferon-alfa treatment during hospitalization [0.540 (0.029, 1.051)], and changes in TC [0.217 (0.069, 0.366)] and HDL [-0.477 (-0.881, -0.074)] levels were significantly associated with changes in the TyG index. Conclusions Our study provided the first evidence that COVID-19 may increase the risk of insulin resistance in patients without diabetes.

We explored the protective effect of spironolactone on cardiac function in the patients undergoing coronary artery bypass grafting (CABG) by determining serum hypoxia-inducible factor-1α (HIF-1α) before and after CABG. We used the propensity score matching method retrospectively to select 174 patients undergoing CABG in our hospital from March 2018 to December 2019. Of the 174 patients, 87 patients taking spironolactone for more than 3 months before CABG were used as a test group and other 87 patients who were not taking spironolactone as a control group. In all patients, serum HIF-1α and troponin I levels were determined before as well as 24 hours and 7 days after CABG, serum N-terminal probrain natriuretic peptide (NT-proBNP) level was determined before as well as 12, 24, and 36 hours after CABG, and electrocardiographic monitoring was performed within 36 hours after CABG. The results indicated that there were no significant differences in the HIF-1α level between the test group and the control group before and 7 days after CABG, but the HIF-1α level was significantly lower in the test group than that in the control group 24 hours after CABG (P < 0.01). The 2 groups were not significantly different in the troponin I level at any time point. There was no significant difference in the serum NT-proBNP level between the test group and the control group before CABG, but NT-proBNP (BNP) levels were all significantly lower in the test group than those in the control group at postoperative 12, 24, and 36 hour time points (all P

To investigate the clinical experience and application value of endoscopic resection of lesions in and around the third ventricle using a transcortical expanded transforaminal transvenous transchoroidal approach with an endoport.Clinical data and follow-up results of seven patients who underwent the removal of lesions in the third ventricle and its adjacent area with an endoport-guided endoscopic system from January 2018 to December 2020 in the Department of Neurosurgery, Zhongshan Hospital Affiliated to Fudan University, were analyzed retrospectively. Two other patients from the Affiliated Pediatric Hospital of Fudan University and the Affiliated Hospital of Guizhou Medical University, respectively, were included in the analysis.A total of nine cases of third ventricle tumors were included in the study, including six women and three men, with an average age of 37.8 years (4-84 years old) and a follow-up time of 6-44 months. These nine tumor cases included two pilocytic astrocytomas, one diffuse midline glioma (H3 K27-altered), two craniopharyngiomas, two choroid plexus (CP) papillomas, one germinoma, and one pineal parenchymal tumor of intermediate differentiation. Total resection was completed in eight cases, with one near-total resection. There were no complications related to the surgical approach, such as epilepsy, aphasia, or hemiplegia.The endoscope transcortical expanded transforaminal transvenous transchoroidal approach using an endoport can safely and effectively remove third ventricle lesions. This approach can reach a wide area, from the anterior to the posterior third ventricle.

Adipocytes take up long chain FAs through diffusion and protein-mediated transport, whereas FA efflux is considered to occur by diffusion. To identify potential membrane proteins that are involved in regulating FA flux in adipocytes, the expression levels of 55 membrane transporters without known function were screened in subcutaneous adipose samples from obese patients before and after bariatric surgery using branched DNA methodology. Among the 33 solute carrier (SLC) transporter family members screened, the expression of 14 members showed significant changes before and after bariatric surgery. One of them, Slc43a3, increased about 2.5-fold after bariatric surgery. Further investigation demonstrated that Slc43a3 is highly expressed in murine adipose tissue and induced during adipocyte differentiation in primary preadipocytes and in OP9 cells. Knockdown of Slc43a3 with siRNA in differentiated OP9 adipocytes reduced both basal and forskolin-stimulated FA efflux, while also increasing FA uptake and lipid droplet accumulation. In contrast, overexpression of Slc43a3 decreased FA uptake in differentiated OP9 cells and resulted in decreased lipid droplet accumulation. Therefore, Slc43a3 seems to regulate FA flux in adipocytes, functioning as a positive regulator of FA efflux and as a negative regulator of FA uptake.

At present, blast furnace ironmaking is still the main process for producing molten iron, and sinters are the main raw material for blast furnace ironmaking. A sinter with good metallurgical performance can not only ensure smooth operation of the blast furnace but also reduce the blast furnace fuel ratio and increase the molten iron production. Structure is the most important factor affecting the metallurgical properties of the sinter. Thus, the research progress of sinter pore and mineral phase structures was reviewed and the mechanism by which they influence sinter properties was expounded. Multiscale characterization methods for the sinter and their advantages and disadvantages were introduced, and the future research direction of sinter was discussed.

There is an inverse relationship between the differentiation of mesenchymal stem cells (MSCs) along either an adipocyte or osteoblast lineage, with lineage differentiation known to be mediated by transcription factors PPARγ and Runx2, respectively. Endogenous ligands for PPARγ are generated during the hydrolysis of triacylglycerols to fatty acids through the actions of lipases such as hormone sensitive lipase (HSL). To examine whether reduced production of endogenous PPARγ ligands would influence bone regeneration, we examined the effects of HSL knockout on fracture repair in mice using a tibial mono-cortical defect as a model. We found an improved rate of fracture repair in HSL-ko mice documented by serial μCT and bone histomorphometry compared to wild-type (WT) mice. Similarly, accelerated rates of bone regeneration were observed with a calvarial model where implantation of bone grafts from HSL-ko mice accelerated bone regeneration at the injury site. Further analysis revealed improved MSC differentiation down osteoblast and chondrocyte lineage with inhibition of HSL. MSC recruitment to the injury site was greater in HSL-ko mice than WT. Finally, we used single cell RNAseq to understand the osteoimmunological differences between WT and HSL-ko mice and found changes in the pre-osteoclast population. Our study shows HSL-ko mice as an interesting model to study improvements to bone injury repair. Furthermore, our study highlights the potential importance of pre-osteoclasts and osteoclasts in bone repair.

ACSL4 is a member of the ACSL family that catalyzes the conversion of long-chain fatty acids to acyl-coenzyme As, which are essential for fatty-acid incorporation and utilization in diverse metabolic pathways, including cholesteryl ester synthesis. Steroidogenic tissues such as the adrenal gland are particularly enriched in cholesteryl esters of long-chain polyunsaturated fatty acids, which constitute an important pool supplying cholesterol for steroid synthesis. The current studies addressed whether ACSL4 is required for normal steroidogenesis. CYP11A1 promoter‒mediated Cre was used to generate steroid tissue‒specific ACSL4 knockout (KO) mice. Results demonstrated that ACSL4 plays an important role in adrenal cholesteryl ester formation, as well as in determining the fatty acyl composition of adrenal cholesteryl esters, with ACSL4 deficiency leading to reductions in cholesteryl ester storage and alterations in cholesteryl ester composition. Statistically significant reductions in corticosterone and testosterone production, but not progesterone production, were observed in vivo, and these deficits were accentuated in ex vivo and in vitro studies of isolated steroid tissues and cells from ACSL4-deficient mice. However, these effects on steroid production appear to be due to reductions in cholesteryl ester stores rather than disturbances in signaling pathways. We conclude that ACSL4 is dispensable for normal steroidogenesis.

Apart from its role in inflammation and immunity, chemerin is also involved in white adipocyte biology. To study the role of chemerin in adipocyte metabolism, we examined the function of chemerin in brown adipose tissue. Brown and white adipocyte precursors were differentiated into adipocytes in the presence of Chemerin siRNA. Chemerin-deficient (Chem(−/−)) mice were compared to wild-type mice when fed a high-fat diet. Chemerin is expressed during brown adipocyte differentiation and knock down of chemerin mRNA results in decreased brown adipocyte differentiation with reduced fatty acid uptake in brown adipocytes. Chem(−/−) mice are leaner than wild-type mice but gain more weight when challenged with high-fat diet feeding, resulting in a larger increase in fat deposition. Chem(−/−) mice develop insulin resistance when on a high-fat diet or due to age. Brown adipose depots in Chem(−/−) mice weigh more than in wild-type mice, but with decreased mitochondrial content and function. Compared to wild-type mice, male Chem(−/−) mice have decreased oxygen consumption, CO(2) production, energy expenditure, and a lower respiratory exchange ratio. Additionally, body temperature of Chem(−/−) mice is lower than that of wild-type mice. These results revealed that chemerin is expressed during brown adipocyte differentiation and has a pivotal role in energy metabolism through brown adipose tissue thermogenesis.

Weifeng Xu,* Haiwang Guan,* Da Gao, Zicheng Wang, Yanna Ba, Hao Yang, Wenjun Shen, Jiangfang Lian, Jianqing Zhou Department of Cardiology, Ningbo Medical Center Lihuili Hospital, Ningbo 315040, People’s Republic of China*These authors contributed equally to this workCorrespondence: Jiangfang Lian; Jianqing ZhouDepartment of Cardiology, Ningbo Medical Center Lihuili Hospital, Ningbo, People’s Republic of ChinaTel +86 13566305960; +86 13780084909Email hjmpin@163.com; 741710363@qq.comIntroduction: Lipoprotein(a) (Lp(a)) is associated with the severity of coronary lesions evaluated using Syntax score in patients with stable coronary artery disease (CAD). However, the effect of low-density lipoprotein cholesterol (LDL-C) levels on the association of Lp(a) levels with Syntax score remains unclear.Methods: A total of 646 patients with stable CAD were enrolled in the present study. Lp(a) levels were measured with an AU5800 Chemistry Analyzer. Syntax scores were calculated by two advanced interventional cardiologists. SPSS 22.0 was used for statistical analyses.Results: The concentration of Lp(a) ranged from 1 to 192 mg/dL. Pearson’s correlation analysis showed a positive correlation between Syntax score and the level of Lp(a) (r = 0.108, p = 0.006). The LDL-C ≥ 100 mg/dL group presented with a higher Lp(a) level, 16 (9– 29) vs 13 (7– 24). Pearson’s correlation analysis identified a correlation between Lp(a) level and Syntax score (r = 0.249, p < 0.001) only in the LDL-C ≥ 100 mg/dL group. Multivariate logistic regression analysis revealed the positive predictive value of an Lp(a) level > 30 mg/dL for a Syntax score ≥ 23 only in the LDL-C ≥ 100 mg/dL group, adjusted odds ratio 2.895, p = 0.010. A receiver operating characteristic curve analysis confirmed the predictive value of Lp(a) levels for a Syntax score ≥ 23 in the LDL-C ≥ 100 mg/dL group with a cutoff value for Lp(a) > 30 mg/dL.Discussion: The association between Lp(a) level and Syntax score was only maintained in the LDL-C ≥ 100 mg/dL group. An Lp(a) level > 30 mg/dL was an independent predictor of a Syntax score ≥ 23 only in the LDL-C ≥ 100 mg/dL group. The effect of LDL-C levels on the association of Lp(a) levels with Syntax score requires further investigations.Keywords: lipoprotein(a), low-density lipoprotein cholesterol, stable coronary artery disease, syntax score

To determine the effects of nordihydroguaiaretic acid (NDGA) on metabolic and molecular changes in response to feeding a typical American fast food or Western diet, mice were fed an American lifestyle-induced obesity syndrome (ALIOS) diet and subjected to metabolic analysis. Male C57BL/6J mice were randomly assigned to the ALIOS diet, the ALIOS diet supplemented with NDGA (NDGA+ALIOS), or a control diet and were maintained on the specific diet for 8 weeks. Mice fed the ALIOS diet showed increased body, liver, and epididymal fat pad weight as well as increased plasma alanine transaminase (ALT) and aspartate aminotransferase (AST) levels (a measure of liver injury) and liver triglyceride content. Coadministration of NDGA normalized body and epididymal fat pad weight, ALT and AST levels, and liver triglycerides. NDGA treatment also improved insulin sensitivity but not glucose intolerance in mice fed the ALIOS diet. In mice fed the NDGA+ALIOS diet, NDGA supplementation induced peroxisome proliferator–activated receptor α (PPARα; the master regulator of fatty acid oxidation) and mRNA levels of carnitine palmitoyltransferases Cpt1c and Cpt2, key genes involved in fatty acid oxidation, compared with the ALIOS diet. NDGA significantly reduced liver endoplasmic reticulum (ER) stress response C/EBP homologous protein, compared with chow or the ALIOS diet, and also ameliorated ALIOS diet–induced elevation of apoptosis signaling protein, caspase 3. Likewise, NDGA downregulated the ALIOS diet–induced mRNA levels of Pparg, fatty acid synthase Fasn, and diacylglycerol acyltransferase Dgat2. NDGA treatment of ALIOS-fed mice upregulated the hepatic expression of antioxidant enzymes, glutathione peroxidase 4, and peroxiredoxin 3 proteins. In conclusion, we provide evidence that NDGA improves metabolic dysregulation by simultaneously modulating the PPARα transcription factor and key genes involved in fatty acid oxidation, key antioxidant and lipogenic enzymes, and apoptosis and ER stress signaling pathways.

Breast cancer is a high-risk heterogeneous disease with myriad subtypes and complicated biological features. The Cancer Genome Atlas (TCGA) breast cancer database provides researchers with the large-scale genome and clinical data via web portals and FTP services. Researchers are able to gain new insights into their related fields, and evaluate experimental discoveries with TCGA. However, it is difficult for researchers who have little experience with database and bioinformatics to access and operate on because of TCGA’s complex data format and diverse files. For ease of use, we build the breast cancer (B-CAN) platform, which enables data customization, data visualization, and private data center. The B-CAN platform runs on Apache server and interacts with the backstage of MySQL database by PHP. Users can customize data based on their needs by combining tables from original TCGA database and selecting variables from each table. The private data center is applicable for private data and two types of customized data. A key feature of the B-CAN is that it provides single table display and multiple table display. Customized data with one barcode corresponding to many records and processed customized data are allowed in Multiple Tables Display. The B-CAN is an intuitive and high-efficient data-sharing platform.

Scavenger receptor class B type 1 (SR-B1), an HDL receptor plays a crucial role in cholesterol metabolism in the liver, steroidogenic tissues, and vascular cells including macrophages. SR-B1 is subject to regulation at the transcription, posttranscription and posttranslational levels. We previously provided evidence that PDZ domain containing NHERF1 and NHERF2 regulate SR-B1 protein levels post-transcriptionally, although the underlying mechanism(s) by which NHERF1 and NHERF2 regulate SR-B1 protein levels is not well understood. In this study, we demonstrate that SR-B1 is degraded intracellularly via ubiquitin-proteasome pathway and that SR-B1 can be ubiquitinated at K500 and K508 residues. Overexpression of NHERF1 or NHERF2 enhanced SR-B1 ubiquitination and degradation. NHERF1 and NHERF2 promote SR-B1 ubiquitination at sites K508 and K500, respectively. These results suggest that NHERF1 and NHERF2 down-regulated SR-B1 at least in part via the ubiquitin/proteasome pathway.

Overweight children and adolescents are at high risk for adult and late life obesity. This report investigates some underlying mechanisms contributing to obesity during early life in an animal model. We generated a strain of transgenic mice, cU2, overexpressing human microRNA 34c, a microRNA functionally implicated in adipogenesis. Male and female cU2 mice exhibit significant weight gain, accompanied by marked increase in abdominal fat mass and metabolic abnormalities, including reduction of both glucose clearance rate and insulin sensitivity, as early as two months of age. Adipogenesis derailment at this early age is suggested by decreased expression of adiponectin, the fat mass and obesity-associated gene, and the adiponectin receptor R1, coupled with a reduction of the brown fat biomarker PAT2 and the adipogenesis inhibitor SIRT1. Notably, adiponectin is an important adipokine and an essential regulator of glucose and fatty acid homeostasis. cU2 mice may provide a crucial animal model for investigating the role of miR-34c in early onset insulin resistance and visceral fat mass increase, contributing to accelerated body weight gain and metabolic disorders. Intervention in this dysregulation may open a new preventive strategy to control early-life weight gain and abnormal insulin resistance, and thus prevalent adult and late life obesity.

SR-B1 belongs to the class B scavenger receptor, or CD36 super family. SR-B1 and CD36 share an affinity for a wide array of ligands. Although they exhibit similar ligand binding specificity, SR-B1 and CD36 have some very specific lipid transport functions. Whereas SR-B1 primarily facilitates the selective delivery of cholesteryl esters (CEs) and cholesterol from HDL particles to the liver and non-placental steroidogenic tissues, as well as participating in cholesterol efflux from cells, CD36 primarily mediates the uptake of long-chain fatty acids in high fatty acid-requiring organs such as the heart, skeletal muscle and adipose tissue. However, CD36 also mediates cholesterol efflux and facilitates selective lipoprotein-CE delivery, although less efficiently than SR-B1. Interestingly, the ability or efficiency of SR-B1 to mediate fatty acid uptake has not been reported. In this paper, using overexpression and siRNA-mediated knockdown of SR-B1, we show that SR-B1 possesses the ability to facilitate fatty acid uptake. Moreover, this function is not blocked by BLT-1, a specific chemical inhibitor of HDL-CE uptake activity of SR-B1, nor by sulfo-N-succinimidyl oleate, which inhibits fatty acid uptake by CD36. Attenuated fatty acid uptake was also observed in primary adipocytes isolated from SR-B1 knockout mice. In conclusion, facilitation of fatty acid uptake is an additional function that is mediated by SR-B1.

Problem Unexplained infertility (UI) represents about 25%-40% of all infertility and is a formidable obstacle for successful pregnancy for child-bearing aged women. However, up to now, there is no reliable method to predict this condition with high accuracy, thereby hindering early management of this condition. Method of study Our prospective study consists of 84 child-bearing aged women that were clinically diagnosed UI. Forty-four matched healthy fertility (HF) women were served as controls. We examined the profiles of 25 hormones and cytokines that were likely related to pathogeneses and molecular pathways involved in UI with the technique of protein array. The samples were randomly stratified 7:3 into a training set and a testing set. We used the SMOTEboost model with 10 serum proteins in a clinical verification study to identify UI cases. Results The predictor had an area under the receiver operating characteristic curve (AUC) of 0.788 with 24 serum protein features. The predictive performance in terms of AUC of the model with the top 10 important serum proteins in the clinical verification study to classify UI cases was 0.809. Three most significantly differentially expressed proteins (DEPs) were prolactin, monocyte chemotactic protein-1 (MCP-1), and leptin. Conclusion Examination of serum-based protein profile changes could help to identify child-bearing aged women at risk of UI. This would enable early detection and facilitate development of clinical strategies to treat UI and guide their planned parenthood. It may also give clues to pathogeneses of the condition of test subjects.

In this work, a sensitive electrochemical aptasensor was designed for lipopolysaccharide (LPS) detection based on Ce-based metal-organic frameworks (Ce-MOFs) and Zn(2+) dependent DNAzyme-assisted recycling as dual signal amplifiers. Herein, Ce-MOFs were decorated with gold nanoparticles (AuNPs) to obtain AuNPs/Ce-MOFs, and the resultant AuNPs/Ce-MOFs not only acted as nanocarriers to capture -SH terminated hairpin probes 2 (HP2) for acquiring HP2/AuNPs/Ce-MOFs signal probes, but also as catalysts to catalyze the oxidation of ascorbic acid (AA). In the presence of target LPS, report DNA was released from the prepared duplex DNA and then hybridized with hairpin probes 1 (HP1, which were immobilized on the electrode). With the help of Zn(2+), report DNA could act as Zn(2+) dependent DNAzyme to cleave HP1 circularly. Then a large amount of capture probes were produced on the electrode to combine with HP2/AuNPs/Ce-MOFs signal probes. When the detection solution contained electrochemical substrate of AA, AuNPs/Ce-MOFs could oxide AA to obtain enhanced signal. Under the optimized conditions, this proposed aptasensor for LPS exhibited a low detection limit of 3.3 fg/mL with a wide linear range from 10fg/mL to 100ng/mL.

This study investigated the effects of SOD2 (MnSOD)-deficiency-induced excessive oxidative stress on ovarian steroidogenesis in vivo and isolated and cultured granulosa cells using WT and Sod2+/- mice. Basal and 48 h eCG-stimulated plasma progesterone levels were decreased ~50% in female Sod2+/- mice, whereas plasma progesterone levels were decreased ~70% in Sod2+/- mice after sequential stimulation with eCG followed by hCG. Sod2+/- deficiency caused about 50% reduction in SOD2 activity in granulosa cells. SOD2-deficiency also caused a marked reduction in progestins and estradiol in isolated granulosa cells. qRT-PCR measurements indicated that the mRNA expression levels of StAR protein and steroidogenic enzymes are decreased in the ovaries of Sod2+/- mice. Further studies showed a defect in the movement of mobilized cytosolic cholesterol to mitochondria. The ovarian membrane from Sod2+/- mice showed higher susceptibility to lipid peroxidation. These data indicates that SOD2-deficiency induced oxidative stress inhibits ovarian granulosa cell steroidogenesis primarily by interfering with cholesterol transport to mitochondria and attenuating the expression of Star protein gene and key steroidogenic enzyme genes.

The scavenger receptor class B type 1 (SR-B1), a high-density lipoprotein (HDL) receptor, is a membrane glycoprotein that mediates selective uptake of HDL-cholesterol and cholesterol ester (CE) into cells. SR-B1 is subject to posttranslational regulation; however, the underlying mechanisms still remain obscure. Here, we identified a novel SR-B1-interacting protein, GIPC1 (GAIP-interacting protein, C terminus 1) that interacts with SR-B1 and stabilizes SR-B1 by negative regulation of its proteasomal and lysosomal degradation pathways. The physiological interaction between SR-B1 and GIPC1 was supported by co-immunoprecipitation of wild-type and mutant GIPC1 constructs in SR-B1 ± GIPC1 overexpressing cells, in native liver cells, and in mouse liver tissues. Overexpression of GIPC1 increased endogenous SR-B1 protein levels, subsequently increasing selective HDL-cholesterol/CE uptake and cellular triglyceride (TG) and total cholesterol (TC) levels, whereas silencing of GIPC1 in the mouse liver was associated with blunted hepatic SR-B1 levels, elevated plasma TG and TC, and attenuated hepatic TG and TC content. A positive correlation was identified between GIPC1 and SR-B1 expression, and both expressions of GIPC1 and SR-B1 from human liver samples were inversely correlated with body mass index (BMI) from human subjects. We therefore conclude that GIPC1 plays a key role in the stability and function of SR-B1 and can also effectively regulate hepatic lipid and cholesterol metabolism. These findings expand our knowledge of the regulatory roles of GIPC1 and suggest that GIPC1 exerts a major effect on cell surface receptors such as SR-B1 and its associated hepatic lipid and cholesterol metabolic processes.

According to the review of the frequent mooring broken cable accidents around the world, this paper analyzes the current situation of port ship mooring operation, and analyzes the innovative research, development and application of mooring technology at home and abroad. In this paper, on the basis of the motion compensation principle of active anti-rolling, and relying on the parallel platform, an intelligent mooring system which can act as both cable and fender function is developed. The system can autonomously adapt to the ship’s six-degree-of-freedom movement, monitor the ship’s load data, and realize the active control of the ship through follow-up and damping, so as to achieve the purpose of autonomously controlling the ship-shore mooring process intellectualization.

Obesity is associated with an increased risk of developing insulin resistance (IR) and type 2 diabetes (T2D). A diverse group of factors including miRNA has been implicated in the pathogenesis of these two metabolic conditions, although underlying molecular mechanisms involved are not well defined. Here, we provide evidence that hepatic miR-125a levels are diminished in both genetic as well as dietary mouse models of obesity. Overexpression of miR-125a enhanced insulin signaling and attenuated cellular lipid accumulation in HepG2 cells and Hepa1-6 cells. Likewise, treatment of mice with ago-miR-125a increased insulin sensitivity, similar to overexpression of miR-125a, whereas treatment of mice with antago-miR-125a blunted the insulin sensitivity. Furthermore, overexpression of miR-125a in mice previously fed a high-fat diet (HFD), significantly improved insulin sensitivity, and attenuated obesity-linked hepatic steatosis and hepatocyte lipid accumulation. In addition, we show that ELOVL fatty acid elongase 6 (Elovl6) is a direct target of miR-125a, and participates in miR-125a mediated regulation of insulin sensitivity and lipid metabolism. These data led us to conclude that dysregulated miR-125a expression augments the development of obesity-induced IR and that miR-125a might serve as a therapeutic target for the development of new drug(s) in the clinical management of metabolic diseases.

In recent years, the prevalence of obesity, metabolic syndrome and type 2 diabetes is increasing dramatically. They share pathophysiological mechanisms and often lead to cardiovascular diseases. The ZDSD rat was suggested as a new animal model to study diabetes and the metabolic syndrome. In the current study, we have further characterized metabolic and hepatic gene expression changes in ZDSD rats. Immuno-histochemical staining of insulin and glucagon on pancreas sections of ZDSD and control SD rats revealed that ZDSD rats have severe damage to their islet structures as early as 15 weeks of age. Animals were followed till they were 26 weeks old, where they exhibited obesity, hypertension, hyperglycemia, dyslipidemia, insulin resistance and diabetes. We found that gene expressions involved in glucose metabolism, lipid metabolism and amino acid metabolism were changed significantly in ZDSD rats. Elevated levels of ER stress markers correlated with the dysregulation of hepatic lipid metabolism in ZDSD rats. Key proteins participating in unfolded protein response pathways were also upregulated and likely contribute to the pathogenesis of dyslipidemia and insulin resistance. Based on its intact leptin system, its insulin deficiency, as well as its timeline of disease development without diet manipulation, this insulin resistant, dyslipidemic, hypertensive, and diabetic rat represents an additional, unique polygenic animal model that could be very useful to study human diabetes.

Background and purpose Previous studies have shown that Creosote bush-derived nordihydroguaiaretic acid (NDGA) exerts beneficial actions on the key components of metabolic syndrome including dyslipidaemia, insulin resistance and hypertension in several relevant rodent models. Here, we synthesized and screened a total of 6 anti-hyperlipidaemic analogues of NDGA and tested their efficacy against hepatic lipid metabolism in a high-fructose diet (HFrD) fed dyslipidaemic rat model. Experimental approach HFrD fed Sprague-Dawley rats treated with NDGA or one of the six analogues were used. Serum samples were analysed for blood metabolites, whereas liver samples were quantified for changes in various mRNA levels by real-time RT-PCR. Key results Oral gavage of HFrD-fed rats for 4 days with NDGA analogues 1 and 2 (100 mg·kg-1 ·day-1 ) suppressed the hepatic triglyceride content, whereas the NDGA analogues 2, 3 and 4, like NDGA, decreased the plasma triglyceride levels by 70-75%. qRT-PCR measurements demonstrated that among NDGA analogues 1, 2, 4 and 5, analogue 4 was the most effective at inhibiting the mRNA levels of some key enzymes and transcription factors involved in lipogenesis. All four analogues almost equally inhibited the key genes involved in triglyceride synthesis and fatty acid elongation. Unlike NDGA, none of the analogues affected the genes of hepatic fatty acid oxidation or transport. Conclusions and implications Our data suggest that NDGA analogues 1, 2, 4 and 5, particularly analogue 4, exert their anti-hyperlipidaemic actions by negatively targeting genes of key enzymes and transcription factors involved in lipogenesis, triglyceride synthesis and fatty acid elongation. These analogues have therapeutic potential.

Cholesterol is an important component of plasma membranes (PMs) and the precursor of all steroid hormones. In steroidogenic tissues, upon hormone stimulation, there is a rapid transfer of cholesterol to the mitochondria, which is the site of the initial step in steroidogenesis. In the current study, we examined PM cholesterol trafficking for steroidogenesis. In a mitochondrial reconstitution assay, adrenal PMs supported steroidogenesis in the absence of additional transport proteins. Depletion of cholesterol in PMs by 50% eliminated the membranes' ability to support steroidogenesis in vitro and reduced steroid production in intact Y1 adrenocortical cells. Syntaxin (STX)-5 and α-soluble N-ethylmaleimide-sensitive factor attachment protein (α-SNAP) are enriched in adrenal PMs, and adrenocorticotropic hormone treatment of rats recruited STX5 and α-SNAP to adrenal PMs and mitochondria. Immunodepletion of STX5 and α-SNAP from PMs decreased steroidogenesis supported by PMs in vitro. Protease digestion of PMs decreased, whereas recombinant STX5 or α-SNAP restored, the PMs' ability to support steroidogenesis. Knockdown of either STX5 or α-SNAP in Y1 cells decreased stimulated steroidogenesis. These results indicate that STX5 and α-SNAP facilitate cholesterol trafficking from PMs to mitochondria for adrenal steroid synthesis and underscore the importance of vesicular trafficking of PM cholesterol for steroidogenesis.-Deng, B., Shen, W.-J., Dong, D., Azhar, S., Kraemer, F. B. Plasma membrane cholesterol trafficking in steroidogenesis.

Previously, apoE-derived ABCA1 agonist peptides have been shown to possess anti-atherosclerotic and possibly antidiabetic properties. Here we assessed the in vitro and in vivo actions of a second generation of ABCA1 peptide agonists, CS6253 and T6991-2, on glucose homeostasis. The results show that these two peptides improve glucose tolerance in a prediabetic diet-induced obesity mouse model by enhancing insulin secretion. It was further demonstrated that T6991-2 also improved glucose tolerance in leptin-deficient (ob/ob) mice. CS6253 increased insulin secretion both under basal conditions and in response to high glucose stimulation in pancreatic INS-1 β-cells rendered leptin receptor deficient with specific siRNA. Additional in vitro cell studies suggest that the CS6253 agonist attenuates hepatic gluconeogenesis and glucose transport. It also potentiates insulin-stimulated glucose uptake and utilization. These observed anti-diabetic actions suggest additional benefits of the CS6253 and T6991-2 ABCA1 peptide agonists for cardiovascular disease beyond their direct anti-atherosclerosis properties previously described.

The Wnt pathway is a new target in bone therapeutic space. WNT proteins are potent stem cell activators and pro-osteogenic agents. Here, we gained insights into the molecular and cellular mechanisms responsible for liposome-reconstituted recombinant human WNT3A protein (L-WNT3A) efficacy to treat osteonecrotic defects. Skeletal injuries were coupled with cryoablation to create non-healing osteonecrotic defects in the diaphysis of the murine long bones. To replicate clinical therapy, osteonecrotic defects were treated with autologous bone graft, which were simulated by using bone graft material from syngeneic ACTB-eGFP-expressing mice. Control osteonecrotic defects received autografts alone; test sites received autografts treated ex vivo with L-WNT3A. In vivo µCT monitored healing over time and immunohistochemistry were used to track the fate of donor cells and assess their capacity to repair osteonecrotic defects according to age and WNT activation status. Collectively, analyses demonstrated that cells from the autograft directly contributed to repair of an osteonecrotic lesion, but this contribution diminished as the age of the donor increased. Pre-treating autografts from aged animals with L-WNT3A restored osteogenic capacity to autografts back to levels observed in autografts from young animals. A WNT therapeutic approach may therefore have utility in the treatment of osteonecrosis, especially in aged patients.