Integrated analysis reveals ceRNA network of cardiac remodeling by SGLT2 inhibitor in middle-aged hypertensive rats.

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) represent an innovative class of antidiabetic agents that have demonstrated promise in mitigating cardiac remodeling. However, the transcriptional regulatory mechanisms underpinning their impact on blood pressure and the reversal of hypertension-induced cardiac remodeling remain largely unexplored. Given this context, our study concentrated on comparing the cardiac expression profiles of lncRNAs and mRNAs between Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHR). To validate our results, we performed blood pressure measurements, tissue staining, and qRT-PCR. The treatment led to a significant reduction in systolic blood pressure and improved cardiac remodeling by reducing myocardial fibrosis and regulating the inflammatory response. Our examination disclosed that ventricular tissue mRNA, regulated by hypertension, was primarily concentrated in the complement and coagulation cascades and cytokine-cytokine receptor interactions. Compared with SHR, the SGLT2i treatment group was associated with myocardial contraction. Investigation into the lncRNA-mRNA regulatory network and competing endogenous RNA (ceRNA) network suggested that the potential roles of these differentially expressed (DE) lncRNAs and mRNAs were tied to processes such as collagen fibril organization, inflammatory response, and extracellular matrix (ECM) modifications. We found that the expression of Col3a1, C1qa, and lncRNA NONRATT007139.2 were altered in the SHR group and that SGLT2i treatment reversed these changes. Our results suggest that dapagliflozin effectively reverses hypertension-induced myocardial remodeling through a lncRNA-mRNA transcriptional regulatory network, with immune cell-mediated ECM deposition as a potential regulatory target. This underlines the potentiality of SGLT2i and genes related to immunity as promising targets for the treatment of hypertension.

Association of domain-specific physical activity with albuminuria among prediabetes and diabetes: a large cross-sectional study.

BACKGROUND: Albuminuria, the presence of excess of protein in urine, is a well-known risk factor for early kidney damage among diabetic/prediabetic patients. There is a complex interaction between physical activity (PA) and albuminuria. However, the relationship of specific-domain PA and albuminuria remained obscure. METHODS: Albuminuria was defined as urinary albumin/creatinine ratio (ACR) > 30 mg/g. PA was self-reported by participants and classified into transportation-related PA (TPA), occupation-related PA (OPA), and leisure-time PA (LTPA). Weighted logistic regression was conducted to compute the odds ratios (ORs) and 95% confidence intervals (CIs). Restricted cubic spline (RCS) was used to evaluate the dose-response of PA domains with the risk of albuminuria. RESULTS: A total of 6739 diabetic/prediabetic patients (mean age: 56.52 ± 0.29 years) were enrolled in our study, including 3181 (47.20%) females and 3558 (52.80%) males. Of them, 1578 (23.42%) were identified with albuminuria, and 5161(76.58%) were without albuminuria. Diabetic/prediabetic patients who adhered the PA guidelines for total PA had a 22% decreased risk of albuminuria (OR = 0.78, 95%CI 0.64-0.95), and those met the PA guidelines for LTPA had a 28% decreased of albuminuria (OR = 0.72, 95%CI 0.57-0.92). However, OPA and TPA were both not associated with decreased risk of albuminuria. RCS showed linear relationship between the risk of albuminuria with LTPA. CONCLUSIONS: Meeting the PA guideline for LTPA, but not OPA and TPA, was inversely related to the risk of albuminuria among diabetic/prediabetic patients. Additionally, achieving more than 300 min/week of LTPA conferred the positive effects in reducing albuminuria among diabetic/prediabetic patients.

Association of MASLD with the risk of extrahepatic cancers: A systematic review and meta-analysis of 18 cohort studies.

BACKGROUND: Numerous recent studies have explored the association between metabolic dysfunction-associated steatotic liver disease (MASLD) and the risk of various extrahepatic cancers. However, the conclusions were inconclusive. The aim of this study was to clarify this relationship by conducting a robust meta-analysis. METHODS: Systematic searches were conducted on PubMed, Embase and Web of Science databases to identify relevant cohort studies published prior to February 2024. Hazard ratios (HRs) and their corresponding 95% confidence intervals (95% CIs) were combined using a random-effects model in this meta-analysis. RESULTS: Eighteen cohort studies (approximately 16.7 million participants) were finally included in this meta-analysis. MASLD was linked to a higher risk of extrahepatic cancers, such as gastric (n = 10, HR = 1.47, 95% CI: 1.07-2.01), colorectal (n = 13, HR = 1.33, 95% CI: 1.16-1.53), pancreatic (n = 8, HR = 1.41, 95% CI: 1.11-1.79), biliary tract (n = 5, HR = 1.27, 95% CI: 1.18-1.37), thyroid (n = 6, HR = 1.46, 95% CI: 1.02-2.09), urinary system (n = 10, HR = 1.45, 95% CI: 1.25-1.69), breast (n = 11, HR = 1.17, 95% CI: 1.08-1.26) and female genital organ cancers (n = 10, HR = 1.36, 95% CI: 1.11-1.66). However, there was no statistically significant association between MASLD and the risk of head and neck (n = 6, HR = 1.03, 95% CI: 99-1.07), oesophageal (n = 9, HR = 1.26, 95% CI: 0.86-1.86), lung (n = 9, HR = 1.01, 95% CI: 0.92-1.10), prostate (n = 9, HR = 1.06, 95% CI: 0.94-1.19) or small intestine cancer (n = 2, HR = 1.75, 95% CI: 1.00-3.06). CONCLUSIONS: This latest large-scale meta-analysis indicated that MASLD was associated with an increased risk of various extrahepatic cancers, such as gastric, colorectal, pancreatic, biliary duct, thyroid, urinary system, breast, skin and female genital cancers. Further research is needed to investigate the mechanisms underlying these associations.

Vonoprazan-amoxicillin dual therapy versus bismuth-containing quadruple therapy for Helicobacter pylori eradication: A systematic review and meta-analysis.

BACKGROUND AND OBJECTIVE: Recently, vonoprazan-amoxicillin (VA) dual therapy has been reported as a promising approach for Helicobacter pylori (H. pylori) eradication. However, the effects of VA therapy versus bismuth-containing quadruple therapy (BQT) on H. pylori eradication remains unclear. The objective of this meta-analysis was to compare the effects of VA dual therapy with BQT for H. pylori eradication. METHODS: A comprehensive search of the literature was conducted from the beginning to September 2023, utilizing PubMed, Embase, the Cochrane Library and Web of Science database. A random-effects model was used to perform a meta-analysis to determine the pooled relative risk (RR) with 95% confidence intervals (CIs). Moreover, trial sequential analysis (TSA) was conducted to evaluate the conclusiveness of the H. pylori eradication rate. RESULTS: Six randomized controlled trials (RCTs) with 1233 patients were included. The VA therapy has similar eradication rate (ITT analysis: 87% vs. 85.7%, RR = 1.01, 95% CI: 0.93-1.09, p = 0.84; PP analysis: 92.5% vs. 93.2%, RR = 1.00, 95% CI: 0.94-1.06, p = 0.97) and compliance (RR = 1.01, 95% CI: 0.99-1.03, p = 0.32) compared to BQT. The VA therapy group had a significantly lower incidence of total adverse events than the BQT group (16.3% vs. 40.0%, RR = 0.45, 95% CI: 0.37-0.55, p < 0.00001). The TSA result showed that the effect was conclusive. CONCLUSIONS: Current evidence indicated that VA therapy is just as successful as BQT in eliminating H. pylori, yet it has fewer adverse events and similar compliance.

Non-alcoholic fatty liver disease and gestational diabetes mellitus: a bidirectional two-sample mendelian randomization study.

PURPOSE: Previous observational studies have revealed a potential link between non-alcoholic fatty liver disease (NAFLD) and gestational diabetes mellitus (GDM), but their causal relationship remains unclear. Thus, this study aimed to examine whether a causal link exists between genetically determined NAFLD and GDM. METHODS: Utilizing publicly accessible genome-wide association studies (GWAS), a two-sample bidirectional Mendelian randomization (MR) analysis was conducted. The GWASs data pertaining to NAFLD and GDM were obtained from the UK Biobank Consortium and FinnGen database in primary analysis, respectively. The random-effects inverse variance weighted (IVW) method was utilized as primary analysis method. Several sensitivity analyses were utilized to verify the robustness of the results. Additionally, we also analyzed the causal effect of potential shared influencing factors on these two conditions. RESULTS: The result of the IVW method showed that there was no significant causal relationship between genetically determined NAFLD and GDM (OR = 0.98, 95% CI: 0.90-1.07, P = 0.691). Similarly, our reverse MR analysis failed to detect a significant causal effect of GDM on NAFLD (OR = 1.14, 95% CI: 0.97-1.36, P = 0.118). Sensitivity analyses further confirmed the robustness of the results. Moreover, we found that genetically determined body mass index, waist-to-hip ratio, triglycerides, and television viewing time may be positively correlated with NAFLD and GDM, while high-density lipoprotein cholesterol and apolipoprotein A-I may both be negatively correlated with NAFLD and GDM. CONCLUSIONS: The current bidirectional MR study failed to provide sufficient genetic evidence for the causal relationship between NAFLD and GDM.

miR-194-3p regulates epithelial-mesenchymal transition in embryonic epicardial cells via p120/ß-catenin signaling.

The epicardium is integral to cardiac development and facilitates endogenous heart regeneration and repair. While miR-194-3p is associated with cellular migration and invasion, its impact on epicardial cells remains uncharted. In this work we use gain-of-function and loss-of-function methodologies to investigate the function of miR-194-3p in cardiac development. We culture embryonic epicardial cells in vitro and subject them to transforming growth factor ß (TGF-ß) treatment to induce epithelial-mesenchymal transition (EMT) and monitor miR-194-3p expression. In addition, the effects of miR-194-3p mimics and inhibitors on epicardial cell development and changes in EMT are investigated. To validate the binding targets of miR-194-3p and its ability to recover the target gene-phenotype, we produce a mutant vector p120-catenin-3'UTR-MUT. In epicardial cells, TGF-ß-induced EMT results in a notable overexpression of miR-194-3p. The administration of miR-194-3p mimics promotes EMT, which is correlated with elevated levels of mesenchymal markers. Conversely, miR-194-3p inhibitor attenuates EMT. Further investigations reveal a negative correlation between miR-194-3p and p120-catenin, which influences ß-catenin level in the cell adhesion pathway. The suppression of EMT caused by the miR-194-3p inhibitor is balanced by silencing of p120-catenin. In conclusion, miR-194-3p directly targets p120-catenin and modulates its expression, which in turn alters ß-catenin expression, critically influencing the EMT process in the embryonic epicardial cells via the cell adhesion mechanism.

Development, validation, and evaluation of a risk assessment tool for personalized screening of gastric cancer in Chinese populations.

BACKGROUND: Effective risk prediction models are lacking for personalized endoscopic screening of gastric cancer (GC). We aimed to develop, validate, and evaluate a questionnaire-based GC risk assessment tool for risk prediction and stratification in the Chinese population. METHODS: In this three-stage multicenter study, we first selected eligible variables by Cox regression models and constructed a GC risk score (GCRS) based on regression coefficients in 416,343 subjects (aged 40-75 years) from the China Kadoorie Biobank (CKB, development cohort). In the same age range, we validated the GCRS effectiveness in 13,982 subjects from another independent Changzhou cohort (validation cohort) as well as in 5348 subjects from an endoscopy screening program in Yangzhou. Finally, we categorized participants into low (bottom 20%), intermediate (20-80%), and high risk (top 20%) groups by the GCRS distribution in the development cohort. RESULTS: The GCRS using 11 questionnaire-based variables demonstrated a Harrell's C-index of 0.754 (95% CI, 0.745-0.762) and 0.736 (95% CI, 0.710-0.761) in the two cohorts, respectively. In the validation cohort, the 10-year risk was 0.34%, 1.05%, and 4.32% for individuals with a low (≤ 13.6), intermediate (13.7~30.6), and high (≥ 30.7) GCRS, respectively. In the endoscopic screening program, the detection rate of GC varied from 0.00% in low-GCRS individuals, 0.27% with intermediate GCRS, to 2.59% with high GCRS. A proportion of 81.6% of all GC cases was identified from the high-GCRS group, which represented 28.9% of all the screened participants. CONCLUSIONS: The GCRS can be an effective risk assessment tool for tailored endoscopic screening of GC in China. Risk Evaluation for Stomach Cancer by Yourself (RESCUE), an online tool was developed to aid the use of GCRS.

Analysis of genetic diversity and genetic structure of Qinchuan cattle conservation population using whole-genome resequencing.

In the conservation of livestock and poultry resources, population genetic diversity and genetic structure of the conservation population are important factors affecting the effectiveness of conservation. In this study, whole-genome resequencing technology was used to detect genomic variation in 100 Qinchuan cattle (30 bulls and 70 cows). By analyzing population genetic diversity, runs of homozygosity (ROH) distribution features, kinship relationships, and family structure, the conservation effectiveness of Qinchuan cattle was comprehensively evaluated. The results showed that a total of 20,968,017 high-quality SNPs were detected in 100 Qinchuan cattle, the average minimum allele frequency was 0.191±0.124, the average polymorphic information content was 0.279±0.131, and the average observed heterozygosity was 0.275±0.131, the average expected heterozygosity is 0.279±0.131, indicating that the genetic diversity of the Qinchuan cattle conservation population is relatively rich. The average identity by state (IBS) distance of the Qinchuan conservation population was 0.243±0.020, with a value of 0.242±0.021 for the bulls. The results of the kinship G-matrix were consistent with the results of the IBS distance matrix, both showing that some individuals in the conservation population had close kinship. A total of 8258 genomic ROH were detected in 100 Qinchuan cattle, with a total length of 9.64 GB. The average length of ROH fragments was 1.167±1.203 Mb, 69.35% of the ROH were short ROH with a length of 0.5~1 Mb, and the average total length of ROH per individual was 96.40 Mb. The average inbreeding coefficient based on ROH was 0.039±0.039, with a value of 0.044±0.035 for the bulls, indicating that some bulls had a certain degree of inbreeding accumulation. The results of the phylogenetic tree combined with kinship analysis showed that the individuals in the Qinchuan cattle conservation population could be divided into eight families, including seven families with bulls and one family without bulls. This study demonstrated that the genetic diversity of the Qinchuan conservation population is relatively rich, with no significant inbreeding accumulation, but there is a risk of inbreeding among some individuals. Therefore, it is necessary to strengthen selection and mating to ensure the sustainable development of Qinchuan cattle resources.

Agrin Yes-associated Protein Promotes the Proliferation of Epicardial Cells.

ABSTRACT: Embryonic epicardial cells make an important contribution to cardiac development. However, their proliferation mechanism is still unclear. Epicardial cells from E12.5 fetal hearts were used in our study. Agrin was used to treat these cells. The expression of Aurora B, Ki67, and pH3 was measured by quantitative reverse transcription-polymerase chain reaction and immunofluorescence. The proportion of cells in G1/S/G2 phase was determined by flow cytometry. The results showed that agrin significantly increased the expression of ki67, pH3, and Aurora B in epicardial cells. Flow cytometry results showed that agrin significantly increased the proportion of epicardial cells in S phase. However, blocking yes-associated protein significantly downregulated the levels of ki67, pH3, and Aurora B and the proportion of epicardial cells in S phase. Thus, our results suggest that agrin may promote the proliferation of epicardial cells by regulating the yes-associated protein activity. This may be useful in exploring heart development mechanisms and preventing congenital heart disease.

Investigation of the underlying genes and mechanism of familial hypercholesterolemia through bioinformatics analysis.

BACKGROUND: Familial hypercholesterolemia (FH) is one of the commonest inherited metabolic disorders. Abnormally high level of low-density lipoprotein cholesterol (LDL-C) in blood leads to premature atherosclerosis onset and a high risk of cardiovascular disease (CVD). However, the specific mechanisms of the progression process are still unclear. Our study aimed to investigate the potential differently expressed genes (DEGs) and mechanism of FH using various bioinformatic tools. METHODS: GSE13985 and GSE6054 were downloaded from the Gene Expression Omnibus (GEO) database for bioinformatic analysis in this study. First, limma package of R was used to identify DEGs between blood samples of patients with FH and those from healthy individuals. Then, the functional annotation of DEGs was carried out by Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis and Gene Ontology (GO) analysis. Based on Search Tool for the Retrieval of Interacting Genes (STRING) tool, we constructed the Protein-Protein Interactions (PPIs) network among DEGs and mined the core genes as well. RESULTS: A total of 102 communal DEGs (49 up-regulated and 53 down-regulated) are identified in FH samples compared with control samples. The functional changes of DEGs are mainly associated with the focal adhere and glucagon signaling pathway. Ten genes (ITGAL, TLN1, POLR2A, CD69, GZMA, VASP, HNRNPUL1, SF1, SRRM2, ITGAV) were identified as core genes. Bioinformatic analysis showed that the core genes are mainly enriched in numerous processes related to cell adhesion, integrin-mediated signaling pathway and cell-matrix adhesion. In the transcription factor (TF) target regulating network, 219 nodes were detected, including 214 DEGs and 5 TFs (SP1, EGR3, CREB, SEF1, HOX13). In conclusion, the DEGs and hub genes identified in this study may help us understand the potential etiology of the occurrence and development of AS. CONCLUSION: Up-regulated ITGAL, TLN1, POLR2A, VASP, HNRNPUL1, SF1, SRRM2, and down-regulated CD69, GZMA and ITGAV performed important promotional effects for the formation of atherosclerotic plaques those suffering from FH. Moreover, SP1, EGR3, CREB, SEF1 and HOX13 were the potential transcription factors for DEGs and could serve as underlying targets for AS rupture prevention. These findings provide a theoretical basis for us to understand the potential etiology of the occurrence and development of AS in FH patients and we may be able to find potential diagnostic and therapeutic targets.

Autophagy is involved in the differentiation of epicardial progenitor cells into vascular smooth muscle cells in mice.

Most coronary smooth muscle cells(CoSMCs) are differentiated from epicardial progenitor cells(EPCs), but the specific mechanism is not fully investigated. Previous studies have shown that autophagy plays an important role for smooth muscle cells(SMCs) differentiation, yet whether autophagy is involved in the differentiation of EPCs into CoSMCs remains unclear. In the present study, We first isolated and cultured EPCs and continuously cultured them for 72 h. Then the autophagy induction and inhibition experiment was established by using the autophagy inducer Rapamycin(RAPA) and the inhibitor 3-Methyladenine(3-MA). And further animal experiments were conducted to observe the effects of autophagy on the development of coronary arteries. Our data showed that autophagy occurred in the differentiation of EPCs into SMCs. Over activation of autophagy may lead to early transient differentiation of EPCs, enhanced migration ability and weakened systolic function, but overall, CoSMC development is still inhibited. However, inhibition of autophagy may delay the differentiation of EPCs, thus reducing the number of coronary arteries. Together, all these processes indicate that autophagy may regulate the differentiation of EPCs into CoSMCs by affecting the time point of differentiation, and appropriate autophagy intensity is required during the development of CoSMCs.

Epicardial fat tissue in patients with diabetes mellitus: a systematic review and meta-analysis.

BACKGROUND: Epicardial fat tissue (EFT) is the visceral fat distributed along the coronary arteries between the pericardium and the myocardium. Increases in EFT are closely related to the occurrence of diabetes mellitus (DM) and cardiovascular disease. To further understand the link between EFT and DM, we conducted a meta-analysis of the relevant literature. METHODS: We systematically searched electronic databases for studies on EFT performed in DM patients and published up to 30 September 2018. We included data on EFT in a DM patient group and a non-DM control group. We then assessed the effect of DM on EFT by meta-analysis and trial sequential analysis (TSA). All statistical analyses were performed using Stata 12.0 and TSA software. RESULTS: A total of 13 studies (n = 1102 patients) were included in the final analysis. Compared with the control group, DM patients had significantly higher EFT (SMD: 1.23; 95% CI 0.98, 1.48; P = 0.000; TSA-adjusted 95% CI 0.91, 2.13; P < 0.0001). The TSA indicated that the available samples were sufficient and confirmed that firm evidence was reached. According to the regression analysis and subgroup analyses, DM typing, EFT ultrasound measurements, total cholesterol (TC) and triglyceride (TG) levels were confounding factors that significantly affected our results. CONCLUSIONS: Our meta-analysis suggests that the amount of EFT is significantly higher in DM patients than in non-DM patients.

Sphingosine 1-phosphate induces epicardial progenitor cell differentiation into smooth muscle-like cells.

Epicardial progenitor cells (EpiCs) which are derived from the proepicardium have the potential to differentiate into coronary vascular smooth muscle cells during development. Whether sphingosine 1-phosphate (S1P), a highly hydrophobic zwitterionic lysophospholipid in signal transduction, induces the differentiation of EpiCs is unknown. In the present study, we demonstrated that S1P significantly induced the expression of smooth muscle cell specific markers α-smooth muscle actin and myosin heavy chain 11 in the EpiCs. And the smooth muscle cells differentiated from the EpiCs stimulated by S1P were further evaluated by gel contraction assay. To further confirm the major subtype of sphingosine 1-phosphate receptors (S1PRs) involved in the differentiation of EpiCs, we used the agonists and antagonists of different S1PRs. The results showed that the S1P1/S1P3 antagonist VPC23019 and the S1P2 antagonist JTE013 significantly attenuated EpiCs differentiation, while the S1P1 agonist SEW2871 and antagonist W146 did not affect EpiCs differentiation. These results collectively suggested that S1P, principally through its receptor S1P3, increases EpiCs differentiation into VSMCs and thus indicated the importance of S1P signaling in the embryonic coronary vasculature, while S1P2 plays a secondary role.

Association Between the Deletion Allele of Ins/Del Polymorphism (Rs145204276) in the Promoter Region of GAS5 with the Risk of Atherosclerosis.

BACKGROUND/AIMS: LncRNA is a growth arrest-specific transcript 5 (GAS5) with tumor suppressor activities in some cancers, but its role in atherosclerosis is unclear. METHODS: Bioinformatics algorithm analysis was utilized to search the target of GAS5 and miR-21, followed by luciferase assay to confirm these targets. Real-time PCR and western-blot were utilized to verify the connection among GAS5, miR-21 and Programmed cell death 4 (PDCD4). MTT assay and flow cytometry analysis were performed to explore the mechanism of GAS5 in the regulation of atherosclerosis. RESULTS: GAS5 directly targets miR-21 and functions as a competing endogenous RNA to suppress miR-21 expression. We also observed that rs145204276 polymorphism, including INS/INS and DEL/DEL, on GAS5 promoter increased transcription activity of GAS5, but the presence of rs145204276 DEL/DEL allele significantly promoted the transcription of GAS5 promoter compared with rs145204276 INS/INS allele. PDCD4 was predicted as a direct target gene of miR-21 with a binding site on PDCD4 3'UTR. It was further confirmed by luciferase assay that miR-21 significantly reduced the luciferase activity of wild-type PDCD4 3'UTR but not that of mutant PDCD4 3'UTR. In addition, high glucose significantly inhibited the growth rate of EC genotyped as DEL/DEL or INS/ INS, and apparently promoted the apoptotic rate of either DEL/DEL or INS/INS genotype ECs. Furthermore, the effect of high glucose was stronger in the INS/INS group, while the expression of GAS5 was dramatically upregulated with the presence of GAS5 DEL/DEL, while GAS5 positively regulated PDCD4 expression via inhibiting miR-21 expression. GAS5 siRNA and miR-21 mimics significantly decreased GAS5 and PDCD4 expressions, and the inhibitory effects of GAS5 siRNA or miR-21 mimics on GAS5 and PDCD4 expressions in the INS/INS group was stronger. Moreover, GAS5 siRNA and miR-21 mimics remarkably triggered cells proliferation and suppressed cell apoptosis, and the inhibition effects of GAS5 siRNA or miR-21 mimics on either cell viability and apoptosis in the INS/INS group was stronger. In this study, we enrolled 1,306 subjects with or without atherosclerosis and found that the INS/DEL or DEL/DEL genotypes significantly decreased the risk of atherosclerosis compared with the ins/ins genotype (adjusted odds ratio: 0.74 and 0.40, respectively). CONCLUSION: In summary, rs145204276 was associated with the risk of atherosclerosis by affecting the proliferation and apoptosis of endothelial cells via regulating the GAS5/miR-21/PDCD4 signaling pathway.

Insulin-like growth factor 1 receptor signaling regulates embryonic epicardial cell proliferation through focal adhesion kinase pathway.

Embryonic epicardial cells (EPCs) can facilitate cardiomyocyte growth through secreting several essential growth factors, and participate in cardiac development through auto-differentiating into many cardiac cell lineages. Proper proliferation of EPCs is the precondition of these functions, so it is quite necessary to explore the mechanisms involving in EPC proliferation. In this study, we aimed to explore whether insulin-like growth factor 1 receptor (IGF1R) signaling participated in regulating the proliferation of EPCs. Our results showed that the expressions of IGF1R and its ligands IGF1 and IGF2 can be clearly spotted on the epicardium layer from E11.5d to E17.5d. Inhibition of IGF1R signaling using picropodophyllin or NVP-AEW541 significantly decreased the proliferation activity and blocked the cell cycle progression of epicardial cells in vitro. On the contrary, activating IGF1R with recombinant IGF1 and IGF2 promoted epicardial cell proliferation and cell cycle. We also found that decreased expression and phosphorylation of FAK in IGF1R inhibitor-treated cells and use of FAK inhibitor Y15 could significantly inhibit the IGFs-induced EPC proliferation. In conclusion, our results suggest that IGF1R signaling plays an important role in regulating EPC proliferation, and this effect may be mediated by FAK pathway.

Long Noncoding RNA H19/miR-675 Axis Promotes Gastric Cancer via FADD/Caspase 8/Caspase 3 Signaling Pathway.

BACKGROUND: Long noncoding RNA (lncRNA) H19 is emerging as a vital regulatory molecule in the progression of different types of cancer and miR-675 is reported to be embedded in H19's first exon. However, their function and specific mechanisms of action have not been fully elucidated. The aim of this study was to identify a novel lncRNA-microRNA-mRNA functional network in gastric cancer. METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was used to assess the relative expression of H19 and miR-675 in normal (GES-1) and gastric cancer cell lines (SGC-7901, SGC-7901/DDP) as well as in tumor tissues. Gain and loss of function approaches were carried out to investigate the potential roles of H19/miR-675 in cell proliferation and apoptosis. Moreover, Fas associated via death domain (FADD) was validated to be the target of miR-675 via luciferase reporter assay. Western blotting was used to evaluate the protein expression of related signaling pathway. RESULTS: In our study H19 and miR-675 were increased in gastric cancer cell lines and tissues. Overexpression of H19 and miR-675 promoted cell proliferation and inhibited cell apoptosis, whereas knockdown of H19 and miR-675 inhibited these effects. By further examining the underlying mechanism, we showed that H19/miR-675 axis inhibited expression of FADD. FADD downregulation subsequently inhibited the caspase cleavage cascades including caspase 8 and caspase 3. CONCLUSION: Taken together, our results point to a novel regulatory pathway H19/miR-675/ FADD/caspase 8/caspase 3 in gastric cancer which may be potential target for cancer therapy.

Triiodothyronine promotes the proliferation of epicardial progenitor cells through the MAPK/ERK pathway.

Thyroid hormone has important functions in the development and physiological function of the heart. The aim of this study was to determine whether 3,5,3'-Triiodothyronine (T3) can promote the proliferation of epicardial progenitor cells (EPCs) and to investigate the potential underlying mechanism. Our results showed that T3 significantly promoted the proliferation of EPCs in a concentration- and time-dependent manner. The thyroid hormone nuclear receptor inhibitor bisphenol A (100 µmol/L) did not affect T3's ability to induce proliferation. Further studies showed that the mRNA expression levels of mitogen-activated protein kinase 1 (MAPK1), MAPK3, and Ki67 in EPCs in the T3 group (10 nmol/L) increased 2.9-, 3-, and 4.1-fold, respectively, compared with those in the control group (P < 0.05). In addition, the mRNA expression of the cell cycle protein cyclin D1 in the T3 group increased approximately 2-fold compared with the control group (P < 0.05), and there were more EPCs in the S phase of the cell cycle (20.6% vs. 12.0%, P < 0.05). The mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) signaling pathway inhibitor U0126 (10 µmol/L) significantly inhibited the ability of T3 to promote the proliferation of EPCs and to alter cell cycle progression. This study suggested that T3 significantly promotes the proliferation of EPCs, and this effect may be achieved through activation of the MAPK/ERK signaling pathway.

Age-dependent down-regulation of hyperpolarization-activated cyclic nucleotide-gated channel 4 causes deterioration of canine sinoatrial node function.

The activity of pacemaker cells in the sinoatrial node (SAN) is an indicator of normal sinus rhythm. Clinical studies have revealed that the dysfunction of the SAN progressively increases with aging. In this study, we determined the changes in hyperpolarization-activated cyclic nucleotide-gated channel 4 (HCN4) expression and the relationship between aging and canine SAN dysfunction. The results of cardiac electrophysiological determination revealed that the intrinsic heart rate decreased from 168 ± 11 beats min-1 in young canines to 120 ± 9 beats min-1 in adults and to 88 ± 9 beats min-1 in aged canines. The sinus node recovery time (SNRT) increased from 412 ± 32 ms in young canines to 620 ± 56 ms in adults and to 838 ± 120 ms in aged canines. Corrected SNRT (CSNRT) increased from 55 ± 12 ms in young canines to 117 ± 27 ms in adults and to 171 ± 37 ms in aged canines. These results indicated that SAN function deteriorated with aging in the canine heart. However, histological staining illustrated that fibrosis was not significantly increased with aging in canine SAN. Real-time polymerase chain reaction indicated that the expression of HCN4 mRNA was downregulated in the elderly canine SAN. Similarly, we also verified that HCN4 protein expression within the SAN declined with aging via immunofluorescence staining and western blot analysis. Taken together, our data show that electrical remodeling, related to the down-regulation of HCN4, is responsible for the gradually increased incidence of SAN dysfunction with aging. Our results provide further evidence for explaining the mechanisms of age-related deterioration in the SAN.

Biological characteristics of embryonic epicardial cells in vitro correlate with embryonic day.

The epicardial cell (EpiC) culture system plays an important role in investigating the specific mechanisms and signaling molecules that are involved in the development of EpiCs. From this early formation until adulthood, EpiCs undergo dynamic changes in the expression of embryonic genes that correlate with changes in the embryonic EpiC properties. The differences of embryonic EpiC properties may affect the related results of experiments in which EpiC culture system is used; however, these differences have not been explored. Therefore, in this study we examined the differences in the biological characteristics of EpiCs on different embryonic days in vitro EpiCs were isolated from embryonic ventricle explants on embryonic day (E) 11.5, E13.5, and E15.5. The differences in the migration, proliferation and differentiation were studied in EpiCs of different embryonic day by scratch assay, cell cycle analysis and platelet derived growth factor-bb (PDGF-BB) treatment. The results showed that EpiCs were successfully cultured from E11.5, E13.5, and E15.5 embryonic ventricle explants. The time windows of E11.5, E13.5, and E15.5 EpiC isolation out of the explants were different. The migration abilities of E11.5, E13.5, and E15.5 EpiCs decreased during embryonic development. Smooth muscle cell differentiation potential of early stage EpiCs was better than that of the later stage EpiCs. Although the proliferation ability of E11.5 EpiCs was significantly weaker than those of E13.5 and E15.5 EpiCs, the proliferation abilities of E13.5 and E15.5 EpiCs did not differ. These results suggest that the biological characteristics of EpiCs correlate with the timing of embryonic development, and different embryonic stage of ventricle should be properly chosen for culturing EpiCs depending on the purposes of the specific experiments.

Angiotensin â ¡ induces the differentiation of mouse epicardial progenitor cells into vascular smooth muscle-like cells.

Epicardial progenitor cells (EpiCs) have a crucial role in cardiac development and vasculature formation. Here we detected the expression of Angiotensin II (Ang II) receptors AT1 and AT2 on EpiCs and demonstrated that AngII could increase the expression of smooth muscle specific markers, including α-smooth muscle actin (α-SMA) and myosin heavy chain 11 (Myh11) in EpiCs. Moreover, the expression of α-SMA and Myh11 induced by Ang II was blocked by pretreatment of EpiCs with the AT1 receptor antagonist losartan, but not the AT2 receptor antagonist PD123319. We further showed that the AngII-induced cells showed significant contractile responses to carbachol. These results implied that AngII could effectively induce EpiCs to differentiate into vascular smooth muscle-like cells through the AT1 receptor.