OBJECTIVES: Over 25% of the global population is affected by metabolic dysfunction-associated fatty liver disease (MAFLD), yet its pathogenesis remains unclear. Endoplasmic reticulum stress (ERS) may be involved in the onset and progression of MAFLD. Adenosine 5'-monophosphate-activated protein kinase α2 (AMPKα2), a key regulator of hepatic energy metabolism, may influence MAFLD development via ERS modulation. This study aims to investigate the role of AMPKα2 in a high-fat diet-induced MAFLD mouse model and its regulatory effect on the inositol-requiring enzyme 1 alpha (IRE1α)-c-Jun N-terminal kinase (JNK) signaling pathway. METHODS: Liver-specific AMPKα2 knockout mice on a C57BL/6 background were generated and subjected to MAFLD induction. Mice were divided into four groups: wild-type control (WT+Chow, basic diet for 12 weeks), wild-type high-fat diet (WT+HFD, high-fat diet for 12 weeks), AMPKα2 knockout control (AMPKα2 KO+Chow), and AMPKα2 knockout high-fat diet (AMPKα2 KO+HFD). Blood glucose, lipid levels, and liver function were assessed post-treatment. Liver histology was analyzed using Oil Red O, hematoxylin-eosin, Masson, and Sirius Red staining. Western blotting was used to evaluate the expression of AMPKα2, ERS markers, autophagy, apoptosis, and ferroptosis-related proteins. RESULTS: Compared with the WT+Chow group, the WT+HFD group showed significantly elevated blood glucose, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) levels (all P<0.01); histological analyses revealed hepatic steatosis, vacuolization, and fibrosis, with a significantly increased non-alcoholic steatohepatitis activity score (NAS) (P<0.001). Phosphorylated IRE1α and the autophagy marker microtubule-associated protein light chain (LC) 3II/LC3I were markedly upregulated, while apoptotic proteins (Cleaved-Caspase 3, BAX, Bcl-2) and ferroptosis markers (SLC7A11, GPX4) showed no significant change (P>0.05). In the AMPKα2 KO+HFD group, blood glucose, ALT, and AST levels were significantly reduced compared to the WT+HFD group. Histological improvements were observed with reduced vacuolization and lipid accumulation. Expression of p-IRE1α, JNK, and LC3II/LC3I was significantly decreased (P<0.05). CONCLUSIONS Hepatic AMPKα2 knockout alleviates high-fat induced MAFLD, potentially by inhibiting the IRE1α-JNK pathway and reducing autophagy.
Animals ; AMP-Activated Protein Kinases/physiology* ; Protein Serine-Threonine Kinases/metabolism* ; Mice, Knockout ; Diet, High-Fat/adverse effects* ; Mice, Inbred C57BL ; Mice ; Endoplasmic Reticulum Stress ; Endoribonucleases/metabolism* ; Male ; Liver/pathology* ; Non-alcoholic Fatty Liver Disease/metabolism* ; MAP Kinase Signaling System/physiology* ; Fatty Liver/metabolism* ; Signal Transduction

OBJECTIVES: Our previous study has verified that high level of SET and MYND domain-containing protein 2 (SMYD2) plays an important role in acquiring aggressive ability for liver cancer cells in hepatocellular carcinoma. MiR-200b as a tumor suppressor gene involves in a variety of cancers. This study aims to investigate the correlation between miR-200b and SMYD2 in hepatocellular carcinoma and the underlying mechanism. METHODS: Firstly, the levels of SMYD2 and miR-200b in hepatocellular carcinoma tissues and matched adjacent non-tumor liver tissues were tested with real-time reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting. Secondly, we evaluated the interaction between miR-200b and SMYD2 using dual-luciferase reporter assay. Thirdly, we elucidated the effect of miR-200b on SMYD2 and its downstream targets p53/CyclinE1. Finally, we silenced SMYD2 in hepatocellular carcinoma cell lines to investigate its effect on tumor proliferation and cell cycle progression, and further confirmed the correlation among SMYD2 and p53/CyclinE1. RESULTS: Compared with the matched adjacent non-tumor liver tissues, miR-200b was obviously decreased, and SMYD2 was significantly increased in hepatocellular carcinoma (both P<0.05). Spearman's rank correlation revealed that miR-200b expression was negatively correlated with SMYD2 (P<0.01). Computer algorithm and dual-luciferase reporter assay revealed that miR-200b directly targeted and suppressed SMYD2 in HEK 293T cells. The down-regulated miR-200b expression promoted hepatoma cell proliferation (P<0.05) and increased SMYD2 expression(P<0.01), while the up-regulated expression of miR-200b had an opposite effect. The knockdown of SMYD2 suppressed the proliferation of MHCC-97L cells (P<0.01), down-regulated CyclinE1, and up-regulated p53 expression (both P<0.05). CONCLUSIONS MiR-200b is involved in hepatocellular carcinoma progression via targeting SMYD2 and regulating SMYD2/p53/CyclinE1 signaling pathway and may be used as a potential target for hepatocellular carcinoma treatment.
Humans ; Carcinoma, Hepatocellular/pathology* ; Tumor Suppressor Protein p53/metabolism* ; MicroRNAs/metabolism* ; Cell Line, Tumor ; Signal Transduction ; Liver Neoplasms/pathology* ; Cell Proliferation/genetics* ; Histone-Lysine N-Methyltransferase/metabolism*

The importance of structural variants(SVs)for human phenotypes and diseases is now recognized.Although a variety of SV detection platforms and strategies that vary in sensitivity and specificity have been developed,few benchmarking procedures are available to confidently assess their performances in biological and clinical research.To facilitate the validation and application of these SV detection approaches,we established an Asian reference material by characterizing the genome of an Epstein-Barr virus(EBV)-immortalized B lymphocyte line along with identified benchmark regions and high-confidence SV calls.We established a high-confidence SV callset with 8938 SVs by integrating four alignment-based SV callers,including 109x Pacific Biosciences(PacBio)continuous long reads(CLRs),22 x PacBio circular consensus sequencing(CCS)reads,104x Oxford Nanopore Technologies(ONT)long reads,and 114×Bionano optical mapping plat-form,and one de novo assembly-based SV caller using CCS reads.A total of 544 randomly selected SVs were validated by PCR amplification and Sanger sequencing,demonstrating the robustness of our SV calls.Combining trio-binning-based haplotype assemblies,we established an SV benchmark for identifying false negatives and false positives by constructing the continuous high-confidence regions(CHCRs),which covered 1.46 gigabase pairs(Gb)and 6882 SVs supported by at least one diploid haplotype assembly.Establishing high-confidence SV calls for a benchmark sample that has been characterized by multiple technologies provides a valuable resource for investigating SVs in human biology,disease,and clinical research.

Objective:To examine the association between parental characteristics and risk of autism spectrum disorder (ASD) in children.Methods:In this case-control study, the cases were defined as children who were diagnosed with ASD and were recruited from June 2018 to February 2019 in Shanghai Mental Center ( n=104). The controls were defined as children who did not have ASD and were recruited in the two community health centers in Jing-an District of Shanghai during the same period ( n=149). All children recruited in this study were 2-6 years old. A multivariate logistic regression model was used to examine the association between parental characteristics and the risk of ASD in offspring, and further to estimate the interaction coefficient. Results:According to multivariate regression analysis, the association between maternal age, previous pregnancy complication and the risk of ASD in children appeared to be not statistically significant. After adjusted, advanced paternal age (≥35 years old)( OR=3.65, 95% CI=1.19-11.15, P=0.023), parental disease before or during pregnancy ( OR=3.34, 95% CI=1.41-7.94, P=0.006) and gender of child (male) ( OR=5.84, 95% CI=2.98-11.44, P<0.001) were associated with increased risk of ASD. The results also showed that the boys whose father was 35 years old or more had a higher risk of ASD than the boys whose fahter was less 35 years old and the girls whose father was 35 years old or more ( P=0.005, P=0.006). Conclusion:Advanced paternal age was associated with increased risk of ASD in offspring and this effect may be more pronounced in boys.

Objective:To examine the association between parental characteristics and risk of autism spectrum disorder (ASD) in children.Methods:In this case-control study, the cases were defined as children who were diagnosed with ASD and were recruited from June 2018 to February 2019 in Shanghai Mental Center ( n=104). The controls were defined as children who did not have ASD and were recruited in the two community health centers in Jing-an District of Shanghai during the same period ( n=149). All children recruited in this study were 2-6 years old. A multivariate logistic regression model was used to examine the association between parental characteristics and the risk of ASD in offspring, and further to estimate the interaction coefficient. Results:According to multivariate regression analysis, the association between maternal age, previous pregnancy complication and the risk of ASD in children appeared to be not statistically significant. After adjusted, advanced paternal age (≥35 years old)( OR=3.65, 95% CI=1.19-11.15, P=0.023), parental disease before or during pregnancy ( OR=3.34, 95% CI=1.41-7.94, P=0.006) and gender of child (male) ( OR=5.84, 95% CI=2.98-11.44, P<0.001) were associated with increased risk of ASD. The results also showed that the boys whose father was 35 years old or more had a higher risk of ASD than the boys whose fahter was less 35 years old and the girls whose father was 35 years old or more ( P=0.005, P=0.006). Conclusion:Advanced paternal age was associated with increased risk of ASD in offspring and this effect may be more pronounced in boys.

Edong Healthcare Group is cited as an example to summarize its practice of centralized purchasing of supplies in the recent two years.In addition to a success in its process and mechanism, the authors analyzed some challenges for the purpose of furthering the group-based reform of public hospitals.

[ ABSTRACT] AIM:To observe the effect of endogenous nitric oxide synthase ( NOS) inhibitor asymmetric dimeth-ylarginine ( ADMA ) and its signaling pathways on NO levels and skeletal muscle contractility in 4-week running rats. METHODS:The 4 weeks running rat model was established.The twitch tension, tetanic tension and the fatigue test of sole-us muscle induced by electrical stimulation ex vivo were detected.The ATP content, mitochondrial DNA levels and the mR-NA expression of peroxisome proliferator-activated receptor γcoactivator-1α(PGC-1α), nuclear respiratory factor (NRF) were measured to reflect the mitochondrial function and biosynthesis in the skeletal muscle.Serum ADMA concentration was detected by high performance liquid chromatography.The endogenous ADMA enzymes PRMT1 and 2 subtypes of ADMA me-tabolism enzyme DDAH, 3 subtypes of NOS protein expression in the skeletal muscle were determined by Western blot.NOS activity and nitric oxide ( NO) content were analyzed by colorimetric method.RESULTS: Compared with normal control group, the twitch tension, tetanic tension and the anti-fatigue capability of soleus muscle in running group were significantly enhanced, ATP content, mitochondrial DNA content and the mRNA expression of PGC-1αand NRF were significantly in-creased (P<0.01).In addition, the protein expression of constitute type NOS (cNOS) and NOS activity were significantly increased (P<0.01), but the increase in NO content was relatively smaller in soleus muscle in exercise group (P<0.05). Moreover, serum ADMA concentration in running group was increased, while the DDAH2 expression in skeletal muscle was decreased.CONCLUSION:Short-term endurance exercise enhances the twitch tension, tetanic tension and fatigue resist-
ance of soleus muscle.The mechanism may be that increased cNOS expression feedbacks to increase ADMA concentration, thus maintaining the increase in NO synthesis at a relatively low level, and resulting in promoting skeletal muscle mitochon-dria biosynthesis and mitochondrial function.

Aim This study was aimed to explore the influence and mechanism of the long-term exercise on skeletal muscle contraction and mitochondrial biosyn-thesis in different muscle fibers.Methods Soleus (SOL)and extensor digitorum longus (EDL)were i-solated from SD male rats with platform running train-ing for eight weeks.The changes of contractility under different electrical stimulation were observed, mito-chondrial biosynthesis,including ATP content,mito-chondrial DNA,the gene expression of PGC-1αand NRF were also detected.Results Long-term endur-ance exercise can improve twitch tension and titanic tension of SOL and EDL ,but only enhanced the fa-tigue resistance in SOL.ATP contents were significant-ly increased in the two types of muscles,but mtDNA content,PGC-1αexpression and NRF translation were only obviously enhanced in SOL,in accompanied with an increase in p-AMPK/AMPK protein ratio.Conclu-sion Long-term endurance exercise increased skeletal muscle contractility and improved the anti-fatigue abili-ty in SOL,which may be associated with increase in mitochondrial biosynthesis via activated AMPK-PGC-1αaxis.

AIM:To investigate the influence of calorie restriction ( CR) on contractility and mitochondrial bi-osynthesis in different types of rat skeletal muscles .METHODS:CR rat model was set up by feeding 60%normal food in-take of control rat every day for 8 weeks.Soleus (SOL) and extensor digitorum longus (EDL) were isolated under anesthe-sia.The twitch tension, titanic tension and fatigue resistance of SOL and EDL in response to electrical stimulation were measured to reflect the contractile function of the muscles .The copy number ratio of mitochondrial gene cytochrome C oxi-dase subunit I ( COX I) to nuclear gene β-actin was determined to evaluate the mitochondrial biosynthesis .ATP content was measured to mirror mitochondrial function .RESULTS:Compared with control group , CR for 8 weeks significantly in-creased twitch tension and titanic tension of both SOL and EDL , but only improved fatigue resistance in SOL .Markedly in-crease in ATP content in both skeletal muscles by CR intervention was observed , especially in SOL .Although CR activated AMP-activated protein kinase (AMPK) in both 2 muscles, up-regulation of mitochondrial biosynthesis and transcription of mitochondrial regulatory genes peroxisome proliferator-activated receptor γcoactivator 1α( PGC-1α) and nuclear respirato-ry factor ( NRF) was only observed in SOL .CONCLUSION:CR for 8 weeks enhanced the contractility of both rat SOL and EDL in response to electrical stimulation , especially in SOL composed of slow-twitch fibers.The mechanisms may be related to the activation of AMPK and the promotion of mitochondrial biosynthesis in SOL .

Diabetes mellitus is a common disease of serious harmful to human health,but its pathogenesis is not entirely clear.Mitochondria are the important organelles to generate energy in eukaryocytes,and play a pivotal role in the regulation of reactive oxygen species generation,intracellular calcium homeostasis,and apoptosis signal transduction.The possible causes of mitochondrial dysfunction include oxidative stress,Ca2+ disturbances,reduction of mitochondrial biosynthesis,opening of mitochondrial permeability transition pore,mitochondrial DNA mutations,and etc..Many studies demonstrate that mitochondrial dysfunction is associated with β-cell dysfunction of type 1 diabetes mellitus and insulin resistance of type 2 diabetes mellitus.Moreover,mitochondrial dysfunction plays important roles in the development of diabetic cardiomyopathy.This present article reviewed the current status of studies on the relationship of mitochondrial dysfunction and diabetes mellitus and diabetic cardiomyopathy.It is very important to understand and study mitochondrial dysfunction and its important roles in diabetes mellitus and diabetic cardiomyopathy in order to clarify the pathogenesis of diabetes mellitus and explore new approaches of prevention and treatment for diabetes mellitus.