Enhancer of zeste homolog 2(EZH2)is a histone methyltransferase It mediates trimethylation of lysine 27 on histone H3,thereby facilitating the epigenetic silencing of downstream genes.In conjunc-tion with SUZ12,EED,and other components,it constitutes the polycomb repressive complex 2(PRC2)complex.While EZH2 is intricately involved in cellular proliferation and cardiac development,the chan-ges in its expression during cardiac terminal differentiation remain elusive.In this study,we employed differential gene expression analysis of embryonic and adult myocardial cells using the GEO database,and found that EZH2 is highly expressed in embryonic myocardium,but is present at very low levels in adult myocardium(P＜0.0001).Conversely,the expression changes of PRC2 members SUZ12 and EED are not as pronounced.Online analysis through the Tabula Muris database indicates that under physiological conditions,various cell subpopulations in the adult mouse heart exhibit negligible expression of EZH2.Immunohistochemical staining of mouse cardiac tissues shows that EZH2 is highly expressed in embryonic and neonatal myocardium but declines progressively from the first day after birth(P＜0.0001),becoming almost undetectable by the third day.Western blotting further confirms the rapid disappearance of EZH2 expression post-birth(P＜0.05),with EZH1 compensating for the downregulation of EZH2 to maintain H3K27me3 modification levels.Additionally,using the P19 teratocarcinoma stem cell model for cardio-myocyte differentiation,it is observed that EZH2 is significantly upregulated during the transition from cardiac progenitor cells to spontaneously beating cardiomyocytes,correlating with the expression of the cardiomyocyte transcription factor Gata4(P＜0.01).Targeted degradation of EZH2 using the small mole-cule drug MS1943 significantly inhibits the proliferation of induced cardiomyocytes,as evidenced by 5-e-thynyl-2'-deoxyuridine(EdU)incorporation assays(P＜0.01),and RT-qPCR reveals a marked in-crease in the expression of the proliferation inhibitor CDKN1A(P＜0.01).In summary,the high expres-sion of EZH2 in embryonic myocardial cells is associated with enhanced cell proliferation.The rapid loss of EZH2 expression postnatally correlates with the loss of proliferative capacity in cardiomyocytes,mark-ing it as a key indicator of cardiac terminal differentiation.

AKT,also known as Protein Kinase B(PKB),plays a critical role in cell proliferation and metabolism.There are three isoforms of AKT:AKT1,AKT2,and AKT3.The effects of these isoforms on the pluripotency and differentiation of mouse embryonic stem cells(mESCs)remain unclear.This study aims to explore the impact of three AKT isoform-specific knockouts on the self-renewal and differen-tiation of mouse embryonic stem cells.Using CRISPR/Cas9 gene-editing technology,AKT isoform-spe-cific knockout cell lines were established.The phenotypic and molecular changes were analyzed through Western blotting,flow cytometry,qRT-PCR,CCK-8 assays,Alkaline Phosphatase(AP)staining,and RNA-seq.The construction of AKT isoform-specific knockout cell lines was successful.The loss of AKT1 and AKT2 inhibited the proliferation of mESCs.The knockout of any single AKT isoform did not affect the expression of pluripotency genes at both mRNA or protein levels.However,during embryoid body forma-tion,the deletion of any of the three AKT isoforms affected the mRNA expression levels of genes in all three germ layers.Transcriptome analysis showed that compared to wild-type mESCs,995,547,and 429 differentially expressed genes(|log2FC|≧1,P＜0.05)were identified inAKT1,AKT2,and AKT3 isoform-specific knockout cells,respectively.There was some overlap in the differentially expressed genes regulated by these three isoforms.In conclusion,the independent knockout of AKT isoforms does not af-fect the maintenance of pluripotency in mouse embryonic stem cells,but they are crucial for differentia-tion.The three AKT isoforms can collectively regulate gene expression while retaining their own regulato-ry specificity.This study provides a foundation for understanding the unique and overlapping roles of AKT isoforms in stem cell biology,highlighting their importance in maintaining stem cell function and differen-tiation.

Diabetic nephropathy(DN)is a serious complication of diabetes mellitus and a leading cause of end-stage renal diseases.In DN patients,key pathological mechanisms include proteinuria,glomerulo-sclerosis,and fibrosis,largely driven by poor glycemic control and oxidative stress caused by prolonged hyperglycemia.This stress damages renal podocytes and triggers inflammatory mesenchymal infiltration of renal tubular cells,exacerbating the progression of proteinuria and fibrosis.Human umbilical cord-de-rived mesenchymal stem cells(hUC-MSCs)offer promising potential for treating DN due to their strong anti-oxidative properties.In this study,we developed a DN mouse model and treated the mouse via tail vein injections of hUC-MSCs(1×106 cells/mouse).The results indicated that hUC-MSCs significantly lowered fasting blood glucose levels(22.5±3.0 vs 14.7±1.1,P＜0.01)and improved glucose toler-ance,as shown by intraperitoneal glucose tolerance test(IPGTT)results(P＜0.05).Additionally,the renal function improved in hUC-MSCs-treated mice,with marked reductions in oxidative stress markers,including blood urea nitrogen(BUN),urinary creatinine(Ucr),urinary protein(PRO),superoxide dismutase(SOD),and malondialdehyde(MDA)(P＜0.05).Histological analyses through hematoxy-lin-eosin(H&E),Periodic Acid-Schiff(PAS),and Sirius red staining demonstrated alleviation of glo-merular mesangial hyperplasia,glomerular hypertrophy,and tubular inflammation.Furthermore,hUC-MSCs treatment downregulated the expression of oxidative stress-related proteins,such as NADPH oxi-dase 4(NOX4)and thioredoxin-interacting protein(TXNIP),and reduced reactive oxygen species(ROS)production(P＜0.05).Meanwhile,human renal cortical proximal tubule epithelial cells(HK-2 cells)were selected for validation in vitro experiments using high glucose treatment followed by super-natants of hUC-MSCs(MSC-CM),and Western blotting showed that the expression of both NOX4 and TXNIP was inhibited(P＜0.05)and ROS expression was reduced.In conclusion,hUC-MSC treatment effectively lowered blood glucose levels and improved renal function in DN mice,likely through the sup-pression of NOX4 expression and TXNIP-mediated oxidative stress.

Objective:To reveal the relationship between fat mass and obesity associated (FTO) protein and the occurrence of diseases in patients with polycystic ovary syndrome (PCOS) combined with metabolic syndrome (MS).Methods:A retrospective case-control study was conducted, and general clinical data and laboratory test indicators of 50 PCOS patients (PCOS group) and 54 healthy individuals (control group) were collected from December 2023 to October 2024. The PCOS group was divided into the PCOS without MS subgroup (PCOS+nMS subgroup, n=25) and the PCOS with MS subgroup (PCOS+MS subgroup, n=25) based on whether MS was present or not. The expression level of serum FTO protein was detected by enzyme-linked immunosorbent assay method. The clinical data and metabolic characteristics of PCOS patients were analyzed, as well as the correlation between serum FTO protein level and the occurrence of PCOS with MS. Receiver operating characteristic (ROC) curves were drew to analyze the predictive ability of serum FTO protein level for PCOS combined MS, and the correlation between serum FTO protein level and metabolic status of PCOS patients was evaluated through logistic regression model. Results:The level of serum FTO protein in the PCOS group [57.42 (45.87, 68.53) μg/L], and PCOS+nMS subgroup [48.41 (37.84, 64.30) μg/L] was all significantly higher than that in the control [45.70 (36.41, 52.86) μg/L, P<0.001; adjusted P=0.016]. The expression level of serum FTO protein in PCOS+MS subgroup [60.31 (50.99, 72.28) μg/L] was significantly higher than that in PCOS+nMS subgroup (adjusted P=0.013) and the control (adjusted P<0.001). The serum FTO protein expression level in the PCOS group was significantly positively correlated with body mass index, waist circumference, systolic blood pressure,diastolic blood pressure, low density lipoprotein cholesterol, homeostasis model to assess insulin resistance index (all P<0.05). The expression level of serum FTO protein had a certain predictive value for PCOS, with an area under the curve (AUC) value of 0.725 (95% CI: 0.627-0.824) and a better predictive value for the occurrence of MS in PCOS, with an AUC value of 0.869 (95% CI: 0.762-0.976) as shown by the ROC curve. Multivariate logistic regression analysis indicated that in PCOS patients, the expression level of serum FTO protein had a significant positive effect on the coexistence of MS, ( OR=1.092,95% CI: 1.010-1.180, P=0.026). Conclusion:PCOS patients have higher serum FTO protein levels than healthy women, and PCOS patients with MS have higher serum FTO protein levels than those without MS. The serum FTO protein level has a good predictive value for the occurrence of PCOS and PCOS complicated with MS, and is an independent risk factor for the occurrence of MS in PCOS.

Hypercholesterolemia is pathologically characterized by abnormal accumulation of low-density lipoprotein cholesterol,which is closely associated with metabolic dysfunction-associated fatty liver disease and increased cardiovascular risks.Hepatocytes maintain cholesterol homeostasis through LDL receptor-mediated uptake and esterification storage mechanisms.However,chronic cholesterol overload induces mitochondrial dysfunction,reactive oxygen species accumulation,and endoplasmic reticulum stress,leading to hepatocyte injury.Moreover,systemic hypercholesterolemia disrupts gut microbiota balance and impairs short-chain fatty acid and ketone metabolism,exacerbating metabolic disturbances and aggravating hepatic injury through enhanced metabolic stress.In this article,we review the advance of studies on hypercholesterolemia in recent years and summary its association with hepatic injury,which can provide theoretical support for further research.

Enhancer of zeste homolog 2(EZH2)is a histone methyltransferase It mediates trimethylation of lysine 27 on histone H3,thereby facilitating the epigenetic silencing of downstream genes.In conjunc-tion with SUZ12,EED,and other components,it constitutes the polycomb repressive complex 2(PRC2)complex.While EZH2 is intricately involved in cellular proliferation and cardiac development,the chan-ges in its expression during cardiac terminal differentiation remain elusive.In this study,we employed differential gene expression analysis of embryonic and adult myocardial cells using the GEO database,and found that EZH2 is highly expressed in embryonic myocardium,but is present at very low levels in adult myocardium(P＜0.0001).Conversely,the expression changes of PRC2 members SUZ12 and EED are not as pronounced.Online analysis through the Tabula Muris database indicates that under physiological conditions,various cell subpopulations in the adult mouse heart exhibit negligible expression of EZH2.Immunohistochemical staining of mouse cardiac tissues shows that EZH2 is highly expressed in embryonic and neonatal myocardium but declines progressively from the first day after birth(P＜0.0001),becoming almost undetectable by the third day.Western blotting further confirms the rapid disappearance of EZH2 expression post-birth(P＜0.05),with EZH1 compensating for the downregulation of EZH2 to maintain H3K27me3 modification levels.Additionally,using the P19 teratocarcinoma stem cell model for cardio-myocyte differentiation,it is observed that EZH2 is significantly upregulated during the transition from cardiac progenitor cells to spontaneously beating cardiomyocytes,correlating with the expression of the cardiomyocyte transcription factor Gata4(P＜0.01).Targeted degradation of EZH2 using the small mole-cule drug MS1943 significantly inhibits the proliferation of induced cardiomyocytes,as evidenced by 5-e-thynyl-2'-deoxyuridine(EdU)incorporation assays(P＜0.01),and RT-qPCR reveals a marked in-crease in the expression of the proliferation inhibitor CDKN1A(P＜0.01).In summary,the high expres-sion of EZH2 in embryonic myocardial cells is associated with enhanced cell proliferation.The rapid loss of EZH2 expression postnatally correlates with the loss of proliferative capacity in cardiomyocytes,mark-ing it as a key indicator of cardiac terminal differentiation.

AKT,also known as Protein Kinase B(PKB),plays a critical role in cell proliferation and metabolism.There are three isoforms of AKT:AKT1,AKT2,and AKT3.The effects of these isoforms on the pluripotency and differentiation of mouse embryonic stem cells(mESCs)remain unclear.This study aims to explore the impact of three AKT isoform-specific knockouts on the self-renewal and differen-tiation of mouse embryonic stem cells.Using CRISPR/Cas9 gene-editing technology,AKT isoform-spe-cific knockout cell lines were established.The phenotypic and molecular changes were analyzed through Western blotting,flow cytometry,qRT-PCR,CCK-8 assays,Alkaline Phosphatase(AP)staining,and RNA-seq.The construction of AKT isoform-specific knockout cell lines was successful.The loss of AKT1 and AKT2 inhibited the proliferation of mESCs.The knockout of any single AKT isoform did not affect the expression of pluripotency genes at both mRNA or protein levels.However,during embryoid body forma-tion,the deletion of any of the three AKT isoforms affected the mRNA expression levels of genes in all three germ layers.Transcriptome analysis showed that compared to wild-type mESCs,995,547,and 429 differentially expressed genes(|log2FC|≧1,P＜0.05)were identified inAKT1,AKT2,and AKT3 isoform-specific knockout cells,respectively.There was some overlap in the differentially expressed genes regulated by these three isoforms.In conclusion,the independent knockout of AKT isoforms does not af-fect the maintenance of pluripotency in mouse embryonic stem cells,but they are crucial for differentia-tion.The three AKT isoforms can collectively regulate gene expression while retaining their own regulato-ry specificity.This study provides a foundation for understanding the unique and overlapping roles of AKT isoforms in stem cell biology,highlighting their importance in maintaining stem cell function and differen-tiation.

Hypercholesterolemia is pathologically characterized by abnormal accumulation of low-density lipoprotein cholesterol,which is closely associated with metabolic dysfunction-associated fatty liver disease and increased cardiovascular risks.Hepatocytes maintain cholesterol homeostasis through LDL receptor-mediated uptake and esterification storage mechanisms.However,chronic cholesterol overload induces mitochondrial dysfunction,reactive oxygen species accumulation,and endoplasmic reticulum stress,leading to hepatocyte injury.Moreover,systemic hypercholesterolemia disrupts gut microbiota balance and impairs short-chain fatty acid and ketone metabolism,exacerbating metabolic disturbances and aggravating hepatic injury through enhanced metabolic stress.In this article,we review the advance of studies on hypercholesterolemia in recent years and summary its association with hepatic injury,which can provide theoretical support for further research.

Nonalcoholic steatohepatitis （NASH） is a chronic metabolic disease characterized by hepatocyte fatty degeneration and ballooning degeneration， and it plays an important role in the progression of hepatic steatosis. Recent studies have shown that immune homeostasis imbalance between T helper 17 （Th17） and regulatory T （Treg） cells are closely associated with the pathological process of NASH. Transforming growth factor-β1 （TGF-β1） is a key cytokine for regulating the differentiation and proliferation of Th17/Treg cells， and TGF-β1 binds to its receptor and activates the Smad signaling pathway， thereby regulating the immune balance of Th17/Treg cells and the expression of inflammatory factors and participating in the repair of liver inflammation. This article systematically reviews the molecular mechanism of the TGF-β1/Smad signaling pathway in affecting NASH by regulating the immune balance of Th17/Treg cells， in order to provide a theoretical basis for the research on the pathogenesis of NASH and related treatment strategies.

Diabetic nephropathy(DN)is a serious complication of diabetes mellitus and a leading cause of end-stage renal diseases.In DN patients,key pathological mechanisms include proteinuria,glomerulo-sclerosis,and fibrosis,largely driven by poor glycemic control and oxidative stress caused by prolonged hyperglycemia.This stress damages renal podocytes and triggers inflammatory mesenchymal infiltration of renal tubular cells,exacerbating the progression of proteinuria and fibrosis.Human umbilical cord-de-rived mesenchymal stem cells(hUC-MSCs)offer promising potential for treating DN due to their strong anti-oxidative properties.In this study,we developed a DN mouse model and treated the mouse via tail vein injections of hUC-MSCs(1×106 cells/mouse).The results indicated that hUC-MSCs significantly lowered fasting blood glucose levels(22.5±3.0 vs 14.7±1.1,P＜0.01)and improved glucose toler-ance,as shown by intraperitoneal glucose tolerance test(IPGTT)results(P＜0.05).Additionally,the renal function improved in hUC-MSCs-treated mice,with marked reductions in oxidative stress markers,including blood urea nitrogen(BUN),urinary creatinine(Ucr),urinary protein(PRO),superoxide dismutase(SOD),and malondialdehyde(MDA)(P＜0.05).Histological analyses through hematoxy-lin-eosin(H&E),Periodic Acid-Schiff(PAS),and Sirius red staining demonstrated alleviation of glo-merular mesangial hyperplasia,glomerular hypertrophy,and tubular inflammation.Furthermore,hUC-MSCs treatment downregulated the expression of oxidative stress-related proteins,such as NADPH oxi-dase 4(NOX4)and thioredoxin-interacting protein(TXNIP),and reduced reactive oxygen species(ROS)production(P＜0.05).Meanwhile,human renal cortical proximal tubule epithelial cells(HK-2 cells)were selected for validation in vitro experiments using high glucose treatment followed by super-natants of hUC-MSCs(MSC-CM),and Western blotting showed that the expression of both NOX4 and TXNIP was inhibited(P＜0.05)and ROS expression was reduced.In conclusion,hUC-MSC treatment effectively lowered blood glucose levels and improved renal function in DN mice,likely through the sup-pression of NOX4 expression and TXNIP-mediated oxidative stress.