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Abstract Background Prostatic acid phosphatase (PAP) and ecto-5'-nucleotidase (NT5E, CD73) produce extracellular adenosine from the nucleotide AMP in spinal nociceptive (pain-sensing) circuits; however, it is currently unknown if these are the main ectonucleotidases that generate adenosine or how rapidly they generate adenosine. Results We found that AMP hydrolysis, when measured histochemically, was nearly abolished in dorsal root ganglia (DRG) neurons and lamina II of spinal cord from Pap/Nt5e double knockout (dKO) mice. Likewise, the antinociceptive effects of AMP, when combined with nucleoside transport inhibitors (dipyridamole or 5-iodotubericidin), were reduced by 80-100% in dKO mice. In addition, we used fast scan cyclic voltammetry (FSCV) to measure adenosine production at subsecond resolution within lamina II. Adenosine was maximally produced within seconds from AMP in wild-type (WT) mice but production was reduced >50% in dKO mice, indicating PAP and NT5E rapidly generate adenosine in lamina II. Unexpectedly, we also detected spontaneous low frequency adenosine transients in lamina II with FSCV. Adenosine transients were of short duration (60%) in frequency in Pap-/-, Nt5e-/- and dKO mice, suggesting these ectonucleotidases rapidly hydrolyze endogenously released nucleotides to adenosine. Field potential recordings in lamina II and behavioral studies indicate that adenosine made by these enzymes acts through the adenosine A1 receptor to inhibit excitatory neurotransmission and nociception. Conclusions Collectively, our experiments indicate that PAP and NT5E are the main ectonucleotidases that generate adenosine in nociceptive circuits and indicate these enzymes transform pulsatile or sustained nucleotide release into an inhibitory adenosinergic signal.

Abstract Background Ecto-5'-nucleotidase (NT5E, also known as CD73) hydrolyzes extracellular adenosine 5'-monophosphate (AMP) to adenosine in nociceptive circuits. Since adenosine has antinociceptive effects in rodents and humans, we hypothesized that NT5E, an enzyme that generates adenosine, might also have antinociceptive effects in vivo. Results To test this hypothesis, we purified a soluble version of mouse NT5E (mNT5E) using the baculovirus expression system. Recombinant mNT5E hydrolyzed AMP in biochemical assays and was inhibited by α,β-methylene-adenosine 5'-diphosphate (α,β-me-ADP; IC50 = 0.43 μM), a selective inhibitor of NT5E. mNT5E exhibited a dose-dependent thermal antinociceptive effect that lasted for two days when injected intrathecally in wild-type mice. In addition, mNT5E had thermal antihyperalgesic and mechanical antiallodynic effects that lasted for two days in the complete Freund's adjuvant (CFA) model of inflammatory pain and the spared nerve injury (SNI) model of neuropathic pain. In contrast, mNT5E had no antinociceptive effects when injected intrathecally into adenosine A1 receptor (A1R, Adora1) knockout mice. Conclusion Our data indicate that the long lasting antinociceptive effects of mNT5E are due to hydrolysis of AMP followed by activation of A1R. Moreover, our data suggest recombinant NT5E could be used to treat chronic pain and to study many other physiological processes that are regulated by NT5E.

The article focuses on research on how small ribonucleic acid (sRNA) regulators contribute to bacterial physiology and stress responses. It provides an analysis of the RNA chaperone Hfq binding and the pairing of the regulatory small RNAs with messenger RNAs. It states that pairing of the sRNA to its target mRNA can result in positive or negative effects on gene translation. It identifies the small RNAs found in Escherichia coli by sequence comparison to closely related enterobacteria.

Familial hypercholesterolemia is an inherited disorder that remains underdiagnosed. Conventional genetic testing methods such as next-generation sequencing (NGS) or target PCR are based on the amplification process. Due to the efficiency limits of polymerase and ligase enzymes, these methods usually target short regions and do not detect large mutations straightforwardly. This study combined the long-read nanopore sequencing and CRISPR-Cas9 system to sequence the target DNA molecules without amplification. We originally designed and optimized the CRISPR-RNA panel to target the low-density lipoprotein receptor gene (LDLR) and proprotein convertase subtilisin/kexin type 9 gene (PCSK9) from human genomic DNA followed by nanopore sequencing. The average coverages for LDLR and PCSK9 were 106× and 420×, versus 1.2× for the background genome. Among them, continuous reads were 52x and 307x, respectively, and spanned the entire length of LDLR and PCSK9. We identified pathogenic mutations in both coding and splicing donor regions in LDLR. We also detected an 11,029 bp large deletion in another case. Furthermore, using continuous long reads generated from the benchmark experiment, we demonstrated how a false-positive 670 bp deletion caused by PCR amplification errors was easily eliminated., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Xu et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Aims: As heart failure (HF) progresses, ATP levels in myocardial cells decrease, and myocardial contractility also decreases. Inotropic drugs improve myocardial contractility but increase ATP consumption, leading to poor prognosis. Kyoto University Substance 121 (KUS121) is known to selectively inhibit the ATPase activity of valosin-containing protein, maintain cellular ATP levels, and manifest cytoprotective effects in several pathological conditions. The aim of this study is to determine the therapeutic effect of KUS121 on HF models., Methods and Results: Cultured cell, mouse, and canine models of HF were used to examine the therapeutic effects of KUS121. The mechanism of action of KUS121 was also examined. Administration of KUS121 to a transverse aortic constriction (TAC)-induced mouse model of HF rapidly improved the left ventricular ejection fraction and improved the creatine phosphate/ATP ratio. In a canine model of high frequency-paced HF, administration of KUS121 also improved left ventricular contractility and decreased left ventricular end-diastolic pressure without increasing the heart rate. Long-term administration of KUS121 to a TAC-induced mouse model of HF suppressed cardiac hypertrophy and fibrosis. In H9C2 cells, KUS121 reduced ER stress. Finally, in experiments using primary cultured cardiomyocytes, KUS121 improved contractility and diastolic capacity without changing peak Ca 2+ levels or contraction time. These effects were not accompanied by an increase in cyclic adenosine monophosphate or phosphorylation of phospholamban and ryanodine receptors., Conclusions: KUS121 ameliorated HF by a mechanism totally different from that of conventional catecholamines. We propose that KUS121 is a promising new option for the treatment of HF., Competing Interests: Declaration of Competing Interest In relation to this manuscript, Kyoto University has applied for a patent (Tokugan 2021–211106), and S.T., C.O., T.H., S.W., A.K., and K.O. are named as inventors on the patent. The other authors declare no competing interests., (Copyright © 2023 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Nonalcoholic steatohepatitis (NASH) can lead to cirrhosis and hepatocellular carcinoma in their advanced stages; however, there are currently no approved therapies. Here, we show that microRNA (miR)-33b in hepatocytes is critical for the development of NASH. miR-33b is located in the intron of sterol regulatory element-binding transcription factor 1 and is abundantly expressed in humans, but absent in rodents. miR-33b knock-in (KI) mice, which have a miR-33b sequence in the same intron of sterol regulatory element-binding transcription factor 1 as humans and express miR-33b similar to humans, exhibit NASH under high-fat diet feeding. This condition is ameliorated by hepatocyte-specific miR-33b deficiency but unaffected by macrophage-specific miR-33b deficiency. Anti-miR-33b oligonucleotide improves the phenotype of NASH in miR-33b KI mice fed a Gubra Amylin NASH diet, which induces miR-33b and worsens NASH more than a high-fat diet. Anti-miR-33b treatment reduces hepatic free cholesterol and triglyceride accumulation through up-regulation of the lipid metabolism-related target genes. Furthermore, it decreases the expression of fibrosis marker genes in cultured hepatic stellate cells. Thus, inhibition of miR-33b using nucleic acid medicine is a promising treatment for NASH., (© 2023 Miyagawa et al.)

Abdominal aortic aneurysm (AAA) is a lethal disease, but no beneficial therapeutic agents have been established to date. Previously, we found that AAA formation is suppressed in microRNA (miR)-33-deficient mice compared with wild-type mice. Mice have only one miR-33, but humans have two miR-33 s, miR-33a and miR-33b. The data so far strongly support that inhibiting miR-33a or miR-33b will be a new strategy to treat AAA. We produced two specific anti-microRNA oligonucleotides (AMOs) that may inhibit miR-33a and miR-33b, respectively. In vitro studies showed that the AMO against miR-33b was more effective; therefore, we examined the in vivo effects of this AMO in a calcium chloride (CaCl 2 )-induced AAA model in humanized miR-33b knock-in mice. In this model, AAA was clearly improved by application of anti-miR-33b. To further elucidate the mechanism, we evaluated AAA 1 week after CaCl 2 administration to examine the effect of anti-miR-33b. Histological examination revealed that the number of MMP-9-positive macrophages and the level of MCP-1 in the aorta of mice treated with anti-miR-33b was significantly reduced, and the serum lipid profile was improved compared with mice treated with control oligonucleotides. These results support that inhibition of miR-33b is effective in the treatment for AAA., (© 2022. The Author(s).)

Background: The mechanisms leading to atrial fibrosis in patients with atrial fibrillation (AF), especially in relation to inflammation, remain unclear., Methods and Results: Forty biomarkers were measured in peripheral blood samples collected prior to catheter ablation, and the association with left atrial (LVZ) was evaluated in 16 consecutive patients. The median %LVZ was 17%. In Pearson's correlation analysis, interleukin(IL)-17A and interferon(IFN)-γ showed the most significant positive and negative correlations with %LVZ (R = 0.35 and 0.43, P < 0.001). Furthermore, the IL-17A/IFN-γ ratio was significantly associated with %LVZ (R = 0.65, P = 0.007), as was the macrophage inflammatory protein (MIP)-1δ/IFN-γ ratio (R = 0.73, P = 0.001). The area under the receiver operator characteristics curves of the IL-17A/IFN-γ and MIP-1δ/IFN-γ ratios for detecting severe LVZ (%LVZ ≥ 10% as a reference standard) were 0.88 and 0.90, respectively. The IL-17A/IFN-γ ratio was significantly higher in patients with severe LVZ than those without (1.41 versus 0.97, P = 0.01). Furthermore, the sensitivity, specificity, and accuracy for detecting severe LVZ were 60%, 100%, and 75.0%, respectively, at a cut-off value of 1.3., Conclusions: Among inflammatory biomarkers, the serum IL-17A/IFN-γ ratio was associated with severe left atrial LVZ in patients with AF. However, further studies are needed to clarify the role of inflammatory biomarkers in the development and progression of atrial fibrosis in patients with AF., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 The Authors.)

Angiotensin-converting enzyme inhibitors (ACEi) delay progression of the inherited renal disease Alport syndrome. However, the effect of ACEis weakens gradually due to an "aldosterone escape". Here, we investigate if an aldosterone antagonist can counteract loss of ACEi-efficacy. COL4A3-/- mice were treated with ramipril (ACEi), starting at 4.5 weeks of age, and spironolactone was added at 7 weeks of age. Lifespan until renal failure, as well as kidney function parameters, were investigated. Dual therapy decreased proteinuria levels compared to ACEi monotherapy. Matrix accumulation, as well as tubulointerstitial and glomerular scar-tissue formation, were significantly reduced compared to untreated mice and ACEi-monotherapy at 75 and 100 days. Lifespan in dual treated mice was extended compared to untreated mice. However, lifespan was not superior to ACEi monotherapy-despite improved urea-nitrogen levels in the dual therapy group. In conclusion, adding the aldosterone-antagonist spironolactone to ACEi therapy further improved kidney function and reduced proteinuria and fibrosis. However, survival was not improved further, possibly due to premature death from side effects of dual therapy such as hyperkalemia. Thus, dual therapy could offer an effective therapy option for Alport syndrome patients with progressive proteinuria. However, the risks of adverse events require close monitoring.

Adaptive thermogenesis is essential for survival, and therefore is tightly regulated by a central neural circuit. Here, we show that microRNA (miR)-33 in the brain is indispensable for adaptive thermogenesis. Cold stress increases miR-33 levels in the hypothalamus and miR-33 -/- mice are unable to maintain body temperature in cold environments due to reduced sympathetic nerve activity and impaired brown adipose tissue (BAT) thermogenesis. Analysis of miR-33 f/f dopamine-β-hydroxylase (DBH)-Cre mice indicates the importance of miR-33 in Dbh-positive cells. Mechanistically, miR-33 deficiency upregulates gamma-aminobutyric acid (GABA) A receptor subunit genes such as Gabrb2 and Gabra4. Knock-down of these genes in Dbh-positive neurons rescues the impaired cold-induced thermogenesis in miR-33 f/f DBH-Cre mice. Conversely, increased gene dosage of miR-33 in mice enhances thermogenesis. Thus, miR-33 in the brain contributes to maintenance of BAT thermogenesis and whole-body metabolism via enhanced sympathetic nerve tone through suppressing GABAergic inhibitory neurotransmission. This miR-33-mediated neural mechanism may serve as a physiological adaptive defense mechanism for several stresses including cold stress.

Recent high-throughput approaches have revealed a vast number of transcripts with unknown functions. Many of these transcripts are long noncoding RNAs (lncRNAs), and intergenic region-derived lncRNAs are classified as long intergenic noncoding RNAs (lincRNAs). Although Myosin heavy chain 6 (Myh6) encoding primary contractile protein is down-regulated in stressed hearts, the underlying mechanisms are not fully clarified especially in terms of lincRNAs. Here, we screen upregulated lincRNAs in pressure overloaded hearts and identify a muscle-abundant lincRNA termed Lionheart. Compared with controls, deletion of the Lionheart in mice leads to decreased systolic function and a reduction in MYH6 protein levels following pressure overload. We reveal decreased MYH6 results from an interaction between Lionheart and Purine-rich element-binding protein A after pressure overload. Furthermore, human LIONHEART levels in left ventricular biopsy specimens positively correlate with cardiac systolic function. Our results demonstrate Lionheart plays a pivotal role in cardiac remodeling via regulation of MYH6.

Objective: This study aims to investigate the time-dependent prognostic utility of two fibrosis markers representing organ fibrogenesis (N-terminal propeptide of procollagen III (PIIINP) and type IV collagen 7S (P4NP 7S)) in patients with acute heart failure (HF)., Methods: 390 patients with acute HF were dichotomised based on the median value of fibrosis markers at discharge. The primary outcome measure was a composite of cardiac death and HF hospitalisation., Results: P4NP 7S significantly declined during hospitalisation, whereas PIIINP did not. The cumulative 90-day and 365-day incidence of the primary outcome measure was 16.6% vs 16.0% (p=0.42) and 33.3% vs 28.4% (p=0.34) in the patients with high versus low PIIINP; 19.9% vs 13.0% (p=0.04) and 32.3% vs 29.0% (p=0.34) in the patients with high and low P4NP 7S, respectively. After adjusting for confounders, high P4NP 7S correlated with significant excess risk relative to low P4NP 7S for both 90-day and 365-day primary outcome measure (adjusted HR, 1.50; 95% CI, 1.02 to 2.21; p=0.04 and adjusted HR, 1.89; 95% CI, 1.11 to 3.26; p=0.02, respectively), which was driven by significant association of high P4NP 7S with higher incidence of HF hospitalisation. Furthermore, P4NP 7S exhibited an additive value to conventional prognostic factors for predicting 90-day outcome (p=0.038 for net reclassification improvement; p=0.0068 for integrated discrimination improvement). High PIIINP did not correlate with significant excess risk for both 90-day and 365-day outcome., Conclusions: This study suggests a possible role of P4NP 7S in the risk stratification of patients with acute HF., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY. Published by BMJ.)

Background Micro RNA (miR)-33 targets cholesterol transporter ATP -binding cassette protein A1 and other antiatherogenic targets and contributes to atherogenic progression. Its inhibition or deletion is known to result in the amelioration of atherosclerosis in mice. However, mice lack the other member of the miR-33 family, miR-33b, which exists in humans and other large mammals. Thus, precise evaluation and comparison of the responsibilities of these 2 miRs during the progression of atherosclerosis has not been reported, although they are essential. Methods and Results In this study, we performed a comprehensive analysis of the difference between the function of miR-33a and miR-33b using genetically modified mice. We generated 4 strains with or without miR-33a and miR-33b. Comparison between mice with only miR-33a (wild-type mice) and mice with only miR-33b (miR-33a -/- /miR-33b +/+ ) revealed the dominant expression of miR-33b in the liver. To evaluate the whole body atherogenic potency of miR-33a and miR-33b, we developed apolipoprotein E-deficient/miR-33a +/+ /miR-33b -/- mice and apolipoprotein E-deficient/miR-33a -/- /miR-33b +/+ mice. With a high-fat and high-cholesterol diet, the apolipoprotein E-deficient/miR-33a -/- /miR-33b +/+ mice developed increased atherosclerotic plaque versus apolipoprotein E-deficient/miR-33a +/+ /miR-33b -/- mice, in line with the predominant expression of miR-33b in the liver and worsened serum cholesterol profile. By contrast, a bone marrow transplantation study showed no significant difference, which was consistent with the relevant expression levels of miR-33a and miR-33b in bone marrow cells. Conclusions The miR-33 family exhibits differences in distribution and regulation and particularly in the progression of atherosclerosis; miR-33b would be more potent than miR-33a.

Background: Copeptin, a surrogate marker of pro-arginine vasopressin, is expected to be a marker in cardiovascular diseases. Its utility for predicting long-term clinical outcomes in heart failure (HF), however, has not been adequately evaluated in daily clinical practice in Japan., Methods: To assess the relationship of serum copeptin at admission with long-term clinical outcomes, we evaluated serum copeptin at admission in consecutive 107 patients hospitalized for HF between April 2011 and July 2012. The primary outcome measure was defined as a composite of all-cause death and re-admission for HF (all-cause death/HF)., Results: In this study population, median serum copeptin at admission was 15.5 (6.7-32.0)pmol/L. As compared with the low-copeptin group (<18pmol/L, N=60), the high-copeptin group (≥18pmol/L, N=47) included more male patients and those with prior myocardial infarction, prior HF, low left ventricular ejection fraction, and chronic kidney disease. During median 4.5 (1.0-5.5) years of clinical follow-up, the cumulative incidence of all-cause death/HF was significantly higher in the high-copeptin than in the low-copeptin group (63.4% versus 33.0% at 1 year, and 85.2% versus 77.2% at 5 years, log-rank p=0.03). After adjusting for confounders, high-copeptin was still an independent predictor for all-cause death/HF [hazard ratio (95% confidence interval): 1.77 (1.04-3.01), p=0.03]., Conclusion: Copeptin was suggested as a useful marker for predicting long-term clinical outcomes in patients with HF., (Copyright © 2018 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.)

Aims: Collagen-derived peptides such as collagen I C-terminal telopeptide (CITP) and procollagen III N-terminal propeptide (PIIINP) have been conventionally used as markers of cardiac fibrosis. Collagen IV 7S domain (P4NP 7S) has been recently reported to be correlated with haemodynamics in patients with acute heart failure. We investigated whether these markers reflect cardiac remodelling and myocardial collagen expression., Methods and Results: In 80 patients with dilated cardiomyopathy, relationships of CITP, PIIINP, and P4NP 7S to clinical and echocardiographic variables were analysed. CITP and PIIINP were inversely correlated with estimated glomerular filtration rate (r = -0.41, P < 0.001 and r = -0.32, P = 0.004, respectively); P4NP 7S was positively correlated with B-type natriuretic peptide (r = 0.32, P = 0.003) and γ-glutamyltransferase (r = 0.38, P < 0.001). These correlations were significant even after adjustment by potential confounders, whereas all three collagen markers were not independently correlated with ejection fraction nor with left ventricular (LV) diastolic diameter. In 33 patients undergoing endomyocardial biopsy, myocardial collagen I and III mRNA expressions were correlated with LV end-diastolic volume index (r = 0.42, P = 0.02 and r = 0.54, P = 0.002, respectively), whereas myocardial collagen IV mRNA expression was not correlated with LV end-diastolic volume index nor with ejection fraction. Each collagen-derived peptide was not significantly correlated with the myocardial expression of their corresponding collagen mRNA., Conclusions: Our study shows that CITP, PIIINP, and P4NP 7S do not reflect myocardial collagen mRNA expression but presumably reflect extra-cardiac organ injury in heart failure., (© 2018 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of the European Society of Cardiology.)

Objective- Atherosclerosis is a common disease caused by a variety of metabolic and inflammatory disturbances. MicroRNA (miR)-33a within SREBF2 (sterol regulatory element-binding factor 2) is a potent target for treatment of atherosclerosis through regulating both aspects; however, the involvement of miR-33b within SREBF1 remains largely unknown. Although their host genes difference could lead to functional divergence of miR-33a/b, we cannot dissect the roles of miR-33a/b in vivo because of lack of miR-33b sequences in mice, unlike human. Approach and Results- Here, we analyzed the development of atherosclerosis using miR-33b knock-in humanized mice under apolipoprotein E-deficient background. MiR-33b is prominent both in human and mice on atheroprone condition. MiR-33b reduced serum high-density lipoprotein cholesterol levels and systemic reverse cholesterol transport. MiR-33b knock-in macrophages showed less cholesterol efflux capacity and higher inflammatory state via regulating lipid rafts. Thus, miR-33b promotes vulnerable atherosclerotic plaque formation. Furthermore, bone marrow transplantation experiments strengthen proatherogenic roles of macrophage miR-33b. Conclusions- Our data demonstrated critical roles of SREBF1-miR-33b axis on both lipid profiles and macrophage phenotype remodeling and indicate that miR-33b is a promising target for treating atherosclerosis.

Recent evidence suggests that the accumulation of macrophages as a result of obesity-induced adipose tissue hypoxia is crucial for the regulation of tissue fibrosis, but the molecular mechanisms underlying adipose tissue fibrosis are still unknown. In this study, we revealed that periostin (Postn) is produced at extraordinary levels by adipose tissue after feeding with a high-fat diet (HFD). Postn was secreted at least from macrophages in visceral adipose tissue during the development of obesity, possibly due to hypoxia. Postn -/- mice had lower levels of crown-like structure formation and fibrosis in adipose tissue and were protected from liver steatosis. These mice also showed amelioration in systemic insulin resistance compared with HFD-fed WT littermates. Mice deficient in Postn in their hematopoietic compartment also had lower levels of inflammation in adipose tissue, in parallel with a reduction in ectopic lipid accumulation compared with the controls. Our data indicated that the regulation of Postn in visceral fat could be beneficial for the maintenance of healthy adipose tissue in obesity.

Objective: Abdominal aortic aneurysm (AAA) is an increasingly prevalent and ultimately fatal disease with no effective pharmacological treatment. Because matrix degradation induced by vascular inflammation is the major pathophysiology of AAA, attenuation of this inflammation may improve its outcome. Previous studies suggested that miR-33 (microRNA-33) inhibition and genetic ablation of miR-33 increased serum high-density lipoprotein cholesterol and attenuated atherosclerosis., Approach and Results: MiR-33a-5p expression in central zone of human AAA was higher than marginal zone. MiR-33 deletion attenuated AAA formation in both mouse models of angiotensin II- and calcium chloride-induced AAA. Reduced macrophage accumulation and monocyte chemotactic protein-1 expression were observed in calcium chloride-induced AAA walls in miR-33 -/- mice. In vitro experiments revealed that peritoneal macrophages from miR-33 -/- mice showed reduced matrix metalloproteinase 9 expression levels via c-Jun N-terminal kinase inactivation. Primary aortic vascular smooth muscle cells from miR-33 -/- mice showed reduced monocyte chemotactic protein-1 expression by p38 mitogen-activated protein kinase attenuation. Both of the inactivation of c-Jun N-terminal kinase and p38 mitogen-activated protein kinase were possibly because of the increase of ATP-binding cassette transporter A1 that is a well-known target of miR-33. Moreover, high-density lipoprotein cholesterol derived from miR-33 -/- mice reduced expression of matrix metalloproteinase 9 in macrophages and monocyte chemotactic protein-1 in vascular smooth muscle cells. Bone marrow transplantation experiments indicated that miR-33-deficient bone marrow cells ameliorated AAA formation in wild-type recipients. MiR-33 deficiency in recipient mice was also shown to contribute the inhibition of AAA formation., Conclusions: These data strongly suggest that inhibition of miR-33 will be effective as a novel strategy for treating AAA., (© 2017 American Heart Association, Inc.)

Determination of mtDNA copy number in the cell is crucial to understand many cellular processes. Recently, the number of studies with the use of mitochondrial DNA (mtDNA) content as the determinant of mitochondrial abnormalities increased greatly and is still growing, therefore, optimization of technical conditions for this analysis is crucial. Despite using similar laboratory protocols, some results cannot be compared between research centers, thus causing discrepancies in the assessment of mtDNA content. The aim of this work was to test which conditions of biological sample collection and storage affect estimation of mtDNA level relative to the nuclear DNA (nDNA) in the blood samples and dermal fibroblasts. We found that the time and temperature of sample storage, as well as the type of the blood sample (whole blood or leukocytes) influence the estimate of mtDNA/nDNA ratio in the blood. In the case of dermal fibroblasts collected from healthy control and Huntington disease patients, our data indicate that the passage number of cells is essential to obtain reliable results.

Cohesinopathies are human genetic disorders that include Cornelia de Lange syndrome (CdLS) and Roberts syndrome (RBS) and are characterized by defects in limb and craniofacial development as well as mental retardation. The developmental phenotypes of CdLS and other cohesinopathies suggest that mutations in the structure and regulation of the cohesin complex during embryogenesis interfere with gene regulation. In a previous project, we showed that RBS was associated with highly fragmented nucleoli and defects in both ribosome biogenesis and protein translation. l-leucine stimulation of the mTOR pathway partially rescued translation in human RBS cells and development in zebrafish models of RBS. In this study, we investigate protein translation in zebrafish models of CdLS. Our results show that phosphorylation of RPS6 as well as 4E-binding protein 1 (4EBP1) was reduced in nipbla/b, rad21 and smc3-morphant embryos, a pattern indicating reduced translation. Moreover, protein biosynthesis and rRNA production were decreased in the cohesin morphant embryo cells. l-leucine partly rescued protein synthesis and rRNA production in the cohesin morphants and partially restored phosphorylation of RPS6 and 4EBP1. Concomitantly, l-leucine treatment partially improved cohesinopathy embryo development including the formation of craniofacial cartilage. Interestingly, we observed that alpha-ketoisocaproate (α-KIC), which is a keto derivative of leucine, also partially rescued the development of rad21 and nipbla/b morphants by boosting mTOR-dependent translation. In summary, our results suggest that cohesinopathies are caused in part by defective protein synthesis, and stimulation of the mTOR pathway through l-leucine or its metabolite α-KIC can partially rescue development in zebrafish models for CdLS., (© The Author 2014. Published by Oxford University Press.)

Background: The mechanism of cardiac energy production against sustained pressure overload remains to be elucidated., Methods and Results: We generated cardiac-specific kinase-dead (kd) calcium/calmodulin-dependent protein kinase kinase-β (CaMKKβ) transgenic (α-MHC CaMKKβkd TG) mice using α-myosin heavy chain (α-MHC) promoter. Although CaMKKβ activity was significantly reduced, these mice had normal cardiac function and morphology at baseline. Here, we show that transverse aortic binding (TAC) in α-MHC CaMKKβkd TG mice led to accelerated death and left ventricular (LV) dilatation and dysfunction, which was accompanied by significant clinical signs of heart failure. CaMKKβ downstream signaling molecules, including adenosine monophosphate-activated protein kinase (AMPK), were also suppressed in α-MHC CaMKKβkd TG mice compared with wild-type (WT) mice. The expression levels of peroxisome proliferator-activated receptor-γ coactivator (PGC)-1α, which is a downstream target of both of CaMKKβ and calcium/calmodulin kinases, were also significantly reduced in α-MHC CaMKKβkd TG mice compared with WT mice after TAC. In accordance with these findings, mitochondrial morphogenesis was damaged and creatine phosphate/β-ATP ratios assessed by magnetic resonance spectroscopy were suppressed in α-MHC CaMKKβkd TG mice compared with WT mice after TAC., Conclusions: These data indicate that CaMKKβ exerts protective effects on cardiac adaptive energy pooling against pressure-overload possibly through phosphorylation of AMPK and by upregulation of PGC-1α. Thus, CaMKKβ may be a therapeutic target for the treatment of heart failure.

MicroRNAs (miRs) are small non-protein-coding RNAs that bind to specific mRNAs and inhibit translation or promote mRNA degradation. Recent reports, including ours, indicated that miR-33a located within the intron of sterol regulatory element-binding protein (SREBP) 2 controls cholesterol homeostasis and can be a possible therapeutic target for treating atherosclerosis. Primates, but not rodents, express miR-33b from an intron of SREBF1. Therefore, humanized mice, in which a miR-33b transgene is inserted within a Srebf1 intron, are required to address its function in vivo. We successfully established miR-33b knock-in (KI) mice and found that protein levels of known miR-33a target genes, such as ABCA1, ABCG1, and SREBP-1, were reduced compared with those in wild-type mice. As a consequence, macrophages from the miR-33b KI mice had a reduced cholesterol efflux capacity via apoA-I and HDL-C. Moreover, HDL-C levels were reduced by almost 35% even in miR-33b KI hetero mice compared with the control mice. These results indicate that miR-33b may account for lower HDL-C levels in humans than those in mice and that miR-33b is possibly utilized for a feedback mechanism to regulate its host gene SREBF1. Our mice will also aid in elucidating the roles of miR-33a/b in different genetic disease models.

Background: Recently, we screened for cardiac genes induced by metabolic stress and identified neural cell adhesion molecule (NCAM) as a candidate. This study aimed to clarify the expression pattern of NCAM in human cardiomyopathy., Methods and Results: A total of 64 cardiac tissue samples of patients with dilated cardiomyopathy were dichotomized according to the immunohistochemically determined signal intensity of NCAM staining (NCAM-high and NCAM-low groups). Clinical and hemodynamic data of the patients were compared between the 2 groups. Fibrosis area, left ventricular end-diastolic volume index, and left ventricular diastolic pressure were greater in the NCAM-high group (22.8% versus 11.6%, P<0.05; 130.3±57.6 versus 104.8±31.7 mL/m(2), P<0.05; 14.3±8.0 versus 8.8±4.7 mm Hg, P<0.005; respectively). Incidence of cardiac death and admission for worsening heart failure was higher in the NCAM-high group during a follow-up of 6.3 years (log-rank P<0.05). Another 18 tissue samples were analyzed to determine the relationships between expression level of NCAM and major metabolic genes as well as hemodynamic parameters. The mRNA level of NCAM correlated with the serum (r=0.58; P=0.01) and mRNA levels (r=0.61; P=0.008) of brain-derived natriuretic peptides. It was also correlated with the mRNA levels of proliferator-activated receptor-γ coactivator-1 α (r=0.69; P=0.002) and the nuclear respiratory factor 1 (r=0.74; P<0.001)., Conclusions: Expression of NCAM was associated with worsening hemodynamic parameters and major metabolic genes. Together with our previous findings, these data support the involvement of NCAM in left ventricular remodeling, revealing new insights into the pathophysiology of heart failure.

MicroRNAs (miRs) are small non-protein-coding RNAs that bind to specific mRNAs and inhibit translation or promote mRNA degradation. Recent reports have indicated that miR-33, which is located within the intron of sterol regulatory element-binding protein (SREBP) 2, controls cholesterol homoeostasis and may be a potential therapeutic target for the treatment of atherosclerosis. Here we show that deletion of miR-33 results in marked worsening of high-fat diet-induced obesity and liver steatosis. Using miR-33(-/-)Srebf1(+/-) mice, we demonstrate that SREBP-1 is a target of miR-33 and that the mechanisms leading to obesity and liver steatosis in miR-33(-/-) mice involve enhanced expression of SREBP-1. These results elucidate a novel interaction between SREBP-1 and SREBP-2 mediated by miR-33 in vivo.

Tissue-specific patterns of gene expression play an important role in the distinctive features of each organ. Small CTD phosphatases (SCPs) 1-3 are recruited by repressor element 1 (RE-1)-silencing transcription factor/neuron-restrictive silencer factor (REST/NRSF) to neuronal genes that contain RE-1 elements, leading to neuronal gene silencing in non-neuronal cells. SCPs are highly expressed in the heart and contain microRNAs (miR)-26b, 26a-2, and 26a-1 with the same seed sequence in their introns. Therefore, we tried to investigate the roles of miR-26b and its host gene in neonatal rat cardiomyocytes. Overexpression of miR-26b suppressed the mRNA expression levels of ANF, βMHC, and ACTA1 and reduced the cell surface area in cardiomyocytes. We confirmed that miR-26b targets the 3' untranslated region (3'UTR) of GATA4 and canonical transient receptor potential channel (TRPC) 3. Conversely, silencing of the endogenous miR-26b family enhanced the expression levels of TRPC3 and GATA4. On the other hand, overexpression of SCP1 induced the mRNA expression of ANF and βMHC and increased the cell surface area in cardiomyocytes. Next, we compared the effect of overexpression of SCP1 with its introns and SCP1 cDNA to observe the net function of SCP1 expression on cardiac hypertrophy. When the expression levels of SCP1 were the same, the overexpression of SCP1 cDNA had a greater effect at inducing cardiac hypertrophy than SCP1 cDNA with its intron. In conclusion, SCP1 itself has the potential to induce cardiac hypertrophy; however, the effect is suppressed by intronic miR-26b in cardiomyocytes. miR-26b has an antagonistic effect on its host gene SCP1., (Copyright © 2012 Wiley Periodicals, Inc.)

Lectin-like oxidized low-density lipoprotein (LDL) receptor-1 (LOX-1) is a receptor for oxidized LDL, and is strongly expressed in endothelial cells at an early stage of atherosclerosis. LOX-1 expression in adipocytes is induced by PPARgamma (ligands and appears to be involved in adipocyte cholesterol metabolism. However, the role of adipose tissue LOX-1 in high-fat diet-induced obesity is unknown. We found that mRNA levels of adipose tissue LOX-1 were markedly increased in obese mice fed a high-fat diet (HFD) compared with those fed normal chow. The levels were closely correlated with those of a proinflammatory cytokine, monocyte chemoattractant protein-1 (MCP-1). Then, LOX-1 knockout (LOX-1-KO) and wild-type (WT) mice were fed HFD for 16weeks. HFD feeding increased the body and mesenteric fat weights similarly in WT and LOX-1-KO mice. HFD-induced expressions of proinflammatory cytokines such as MCP-1, MIP-1alpha, and IL-6 were significantly less in LOX-1-KO than WT mice. Thus, LOX-1 is required for the HFD-induced expression of proinflammatory cytokines in the adipose tissue of obese mice., (Copyright 2010 Elsevier Inc. All rights reserved.)

We used retrovirus insertion-mediated random mutagenesis to generate tumor necrosis factor-alpha (TNF-alpha)-resistant lines from L929 cells. Using this approach, we discovered that caveolin-1 alpha is required for TNF-alpha-induced cell death in L929 cells. The need for caveolin-1 alpha in TNF-alpha-induced cell death was confirmed by the restoration of sensitivity to TNF-alpha after ectopic reconstitution of caveolin-1 alpha/beta expression. This caveolin-1 alpha-mutated line was also resistant to H(2)O(2) and staurosporine, but not to lonidamine. HepG2 cells are known to lack endogenous caveolins. HepG2 cells stably transfected with caveolin-1 alpha/beta were found to be much more sensitive to TNF-alpha than either parental cells transfected with caveolin-1 beta or parental cells transfected with an empty vector. In contrast to its extensively documented antiapoptotic effect, the elevated activity of Akt appears to be important in sensitizing caveolin-1-expressing cells to TNF-alpha, since pretreatment of cells with the phosphatidylinositide 3-kinase (PI3K) inhibitor LY-294002 or wortmannin completely blocked PI3K activation and markedly improved the survival of TNF-alpha-treated L929 cells. The survival rates of caveolin-1 alpha-normal and caveolin-1 alpha-deficient L929 cells were comparable after treatment with PI3K inhibitor and TNF-alpha. Similar results were obtained with HepG2 cells that stably expressed caveolin-1 alpha/beta or -beta and parental cells transfected with an empty vector. In summary, our results indicate that caveolin-1 alpha preferentially sensitizes L929 cells to TNF-alpha through the activation of a PI3K/Akt signaling pathway.

Endothelin-1 (ET-1) is a potent survival factor that protects cardiac myocytes from apoptosis. ET-1 induces cardiac gene transcription and protein expression of antiapoptotic B cell leukemia-2 (bcl-2) in a calcineurin-dependent manner. A cellular target of adenovirus early region 1A (E1A) oncoprotein, p300 also activates bcl-2 transcription in cardiac myocytes and is required for their survival. p300 acts as a calcineurin-regulated nuclear factors of activated T lymphocytes (NFATc), downstream targets of calcineurin. In addition, the bcl-2 promoter contains multiple NFAT consensus sequences. These findings prompted us to investigate the role of NFATc in ET-1-dependent and p300-dependent bcl-2 transcription in cardiac myocytes. In primary cardiac myocytes prepared from neonatal rats, mutation of 2 NFAT sites within the bcl-2 promoter completely abolished the ET-1- and p300-induced increases in the activity of this promoter. We show here that p300 markedly potentiates the binding of NFATc1 to the bcl-2 NFAT element by interacting with NFATc1 in an E1A-dependent manner. On the other hand, stimulation of cardiac myocytes with ET-1 causes nuclear translocation of NFATc1, which interacts with p300 and increases DNA binding. Expression of E1A did not change the cardiac nuclear localization of NFATc1 but blocked its interaction with p300, DNA binding, and bcl-2 promoter activation. These findings suggest that ET-1-dependent NFATc signaling associates with p300 in the transactivation of bcl-2 gene in cardiac myocytes.

Hemin was covalently connected to two 9-aminoacridines (9AA) through its two propionates, and the binding properties of this bis-dentate compound (hemin(9AA)2) to DNA were examined by visible absorption spectroscopy. The binding affinity of the hemin(9AA)2 was found to be higher than that of the hemin, and this should be attributed to the two linked acridine moieties. The binding constant (K) and the number of binding sites per nucleotide (n) were estimated by Scatchard plot analyses. Though the order of the K value of hemin(9AA)2 was similar to that of 9AA, the hemin(9AA)2 was analyzed to have a smaller n value, the order of which was of about 10(-4). The small n value may reflect the sequence specificity of the bis-dentate hemin(9AA)2 on binding to the DNA.

In order to achieve a higher degree of improvement in patients with postoperative hepatic failure, the effects of plasma adsorption (PA) using a serial connection of noncoated charcoal (N 350) and a new bilirubin adsorbent material, styrenedivinylbenzene (BR350), were investigated both experimentally and clinically. After in vitro perfusion of high bilirubin containing plasma through these columns for 3 hours, total bilirubin levels were drastically reduced to 21% of the preperfusion level in the serial connection of N 350 and BR 350, while it remained high at over 40% in the single use of each column. Total branched chain and aromatic amino acid levels were also drastically reduced in the serial connection of these columns to 50, 40, and 7%, respectively, while the total amino acid levels remained high at 87% in the single use of BR 350. The combination of these columns enhanced rather than interfered with one another. Patients who received this treatment achieved an initial reduction of plasma total bilirubin and aromatic amino acids of 57 +/- 6 and 84 +/- 7, respectively. Although the long-term prognosis for these patients was negative, improvement of clinical and laboratory findings were actually obtained by this treatment. This PA system could provide a possibility for an improved supportive therapy for hepatic failure, especially for patients with hepatic coma and hyperbilirubinemia.