Oxytocin Protects Against Isoproterenol-Induced Cardiac Hypertrophy by Inhibiting PI3K/AKT Pathway via a lncRNA GAS5/miR-375-3p/KLF4-Dependent Mechanism

Oxytocin attenuates cardiac hypertrophy by improving cardiac glucose metabolism and regulating OXTR/JAK2/STAT3 axis

BACKGROUND

The progress of cardiac hypertrophy is modulated by JAK2/STAT3 signaling pathway. Cardiac glucose metabolism derangement exacerbates the progression of cardiac hypertrophy. Oxytocin (OT) has emerged as a significant hormone involved in cardiovascular homeostasis, especially in protecting against cardiac hypertrophy. The present study aims to explore whether the anti-hypertrophy effect of oxytocin is related to the JAK2/STAT3 signaling pathway and cardiac glucose metablism.

METHODS

Cardiac hypertrophy model was induced by angiotensin II (Ang II) in H9c2 cells and in mice with or without oxytocin treatment. Changes in cardiac histopathology were evaluated by hematoxylin and eosin (H&E), Masson staining, and wheat germ agglutinin (WGA) staining. The hypertrophy-related genes and JAK2/STAT3 pathway signaling molecules were analyzed by qRT-PCR and western blotting. The levels of glucose, pyruvic acid, lactic acid, and lactate dehydrogenase activity in H9c2 cells using the corresponding assay kits.

RESULTS

The results showed that OT inhibited hypertrophic and fibrotic changes. Furthermore, OT increased intracellular levels of glucose and pyruvic acid, and decreased lactate dehydrogenase activity and lactic acid levels. Mechanistically, Ang II decreased oxytocin receptors (OXTR) expression and facilitated JAK2 and STAT3 phosphorylation. OT treatment increased OXTR expression and blocked JAK2 and STAT3 phosphorylation The OXTR-specific siRNA-mediated depleted expression could abrogate OT-induced anti-hypertrophic effects in H9c2 cells following angiotensin II insult. However, the JAK2/STAT3 inhibitor AG490 rescued the protective effects of OT against cardiac hypertrophy under OXTR downregulation.

CONCLUSION

OT exerts its protective effects against cardiac hypertrophy by improving cardiac glucose metabolism and regulating OXTR/JAK2/STAT3 axis.

Role of oxytocin in bone

Oxytocin (OT) is a posterior pituitary hormone that, in addition to its role in regulating childbirth and lactation, also exerts direct regulatory effects on the skeleton through peripheral OT and oxytocin receptor (OTR). Bone marrow mesenchymal stem cells (BMSCs), osteoblasts (OB), osteoclasts (OC), chondrocytes, and adipocytes all express OT and OTR. OT upregulates RUNX2, BMP2, ALP, and OCN, thereby enhancing the activity of BMSCs and promoting their differentiation towards OB rather than adipocytes. OT also directly regulates OPG/RANKL to inhibit adipocyte generation, increase the expression of SOX9 and COMP, and enhance chondrocyte differentiation. OB can secrete OT, exerting influence on the surrounding environment through autocrine and paracrine mechanisms. OT directly increases OC formation through the NκB/MAP kinase signaling pathway, inhibits osteoclast proliferation by triggering cytoplasmic Ca2+ release and nitric oxide synthesis, and has a dual regulatory effect on OCs. Under the stimulation of estrogen, OB synthesizes OT, amplifying the biological effects of estrogen and OT. Mediated by estrogen, the OT/OTR forms a feedforward loop with OB. Apart from estrogen, OT also interacts with arginine vasopressin (AVP), prostaglandins (PGE2), leptin, and adiponectin to regulate bone metabolism. This review summarizes recent research on the regulation of bone metabolism by OT and OTR, aiming to provide insights into their clinical applications and further research.

Liraglutide ameliorates TAC-induced cardiac hypertrophy and heart failure by upregulating expression level of ANP expression

Recent studies have underscored the cardioprotective properties of liraglutide. This research explores its impact on cardiac hypertrophy and heart failure following transverse aortic constriction (TAC). We found that liraglutide administration markedly ameliorated cardiac hypertrophy, fibrosis, and function. These benefits correlated with increased ANP expression and reduced activity in the calcineurin A/NFATc3 signaling pathway. Moreover, liraglutide mitigated ER stress and cardiomyocyte apoptosis, and enhanced autophagy. Notably, the positive effects of liraglutide diminished when co-administered with A71915, an ANP inhibitor, suggesting that ANP upregulation is critical to its cardioprotective mechanism.

Potential molecular and cellular mechanisms of the effects of cuproptosis-related genes in the cardiomyocytes of patients with diabetic heart failure: a bioinformatics analysis

Background

Diabetes mellitus is an independent risk factor for heart failure, and diabetes-induced heart failure severely affects patients' health and quality of life. Cuproptosis is a newly defined type of programmed cell death that is thought to be involved in the pathogenesis and progression of cardiovascular disease, but the molecular mechanisms involved are not well understood. Therefore, we aimed to identify biomarkers associated with cuproptosis in diabetes mellitus-associated heart failure and the potential pathological mechanisms in cardiomyocytes.

Materials

Cuproptosis-associated genes were identified from the previous publication. The GSE26887 dataset was downloaded from the GEO database.

Methods

The consistency clustering was performed according to the cuproptosis gene expression. Differentially expressed genes were identified using the limma package, key genes were identified using the weighted gene co-expression network analysis(WGCNA) method, and these were subjected to immune infiltration analysis, enrichment analysis, and prediction of the key associated transcription factors. Consistency clustering identified three cuproptosis clusters. The differentially expressed genes for each were identified using limma and the most critical MEantiquewhite4 module was obtained using WGCNA. We then evaluated the intersection of the MEantiquewhite4 output with the three clusters, and obtained the key genes.

Results

There were four key genes: HSDL2, BCO2, CORIN, and SNORA80E. HSDL2, BCO2, and CORIN were negatively associated with multiple immune factors, while SNORA80E was positively associated, and T-cells accounted for a major proportion of this relationship with the immune system. Four enriched pathways were found to be associated: arachidonic acid metabolism, peroxisomes, fatty acid metabolism, and dorsoventral axis formation, which may be regulated by the transcription factor MECOM, through a change in protein structure.

Conclusion

HSDL2, BCO2, CORIN, and SNORA80E may regulate cardiomyocyte cuproptosis in patients with diabetes mellitus-associated heart failure through effects on the immune system. The product of the cuproptosis-associated gene LOXL2 is probably involved in myocardial fibrosis in patients with diabetes, which leads to the development of cardiac insufficiency.

Krüpple-like factors in cardiomyopathy: emerging player and therapeutic opportunities

Cardiomyopathy, a heterogeneous pathological condition characterized by changes in cardiac structure or function, represents a significant risk factor for the prevalence and mortality of cardiovascular disease (CVD). Research conducted over the years has led to the modification of definition and classification of cardiomyopathy. Herein, we reviewed seven of the most common types of cardiomyopathies, including Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC), diabetic cardiomyopathy, Dilated Cardiomyopathy (DCM), desmin-associated cardiomyopathy, Hypertrophic Cardiomyopathy (HCM), Ischemic Cardiomyopathy (ICM), and obesity cardiomyopathy, focusing on their definitions, epidemiology, and influencing factors. Cardiomyopathies manifest in various ways ranging from microscopic alterations in cardiomyocytes, to tissue hypoperfusion, cardiac failure, and arrhythmias caused by electrical conduction abnormalities. As pleiotropic Transcription Factors (TFs), the Krüppel-Like Factors (KLFs), a family of zinc finger proteins, are involved in regulating the setting and development of cardiomyopathies, and play critical roles in associated biological processes, including Oxidative Stress (OS), inflammatory reactions, myocardial hypertrophy and fibrosis, and cellular autophagy and apoptosis, particularly in diabetic cardiomyopathy. However, research into KLFs in cardiomyopathy is still in its early stages, and the pathophysiologic mechanisms of some KLF members in various types of cardiomyopathies remain unclear. This article reviews the roles and recent research advances in KLFs, specifically those targeting and regulating several cardiomyopathy-associated processes.

Ovarian Tumor Domain-Containing 7B Attenuates Pathological Cardiac Hypertrophy by Inhibiting Ubiquitination and Degradation of Krüppel-Like Factor 4

BACKGROUND

Cardiac hypertrophy (CH) is a well-established risk factor for many cardiovascular diseases and a primary cause of mortality and morbidity among older adults. Currently, no pharmacological interventions have been specifically tailored to treat CH. OTUD7B (ovarian tumor domain-containing 7B) is a member of the ovarian tumor-related protease (OTU) family that regulates many important cell signaling pathways. However, the role of OTUD7B in the development of CH is unclear. Therefore, we investigated the role of OTUD7B in CH.

METHODS AND RESULTS

OTUD7B knockout mice were used to assay the role of OTUD7B in CH after transverse aortic coarctation surgery. We further assayed the specific functions of OTUD7B in isolated neonatal rat cardiomyocytes. We found that OTUD7B expression decreased in hypertrophic mice hearts and phenylephrine-stimulated neonatal rat cardiomyocytes. Furthermore, OTUD7B deficiency exacerbated transverse aortic coarctation surgery-induced myocardial hypertrophy, abnormal cardiac function, and fibrosis. In cardiac myocytes, OTUD7B knockdown promoted phenylephrine stimulation-induced myocardial hypertrophy, whereas OTUD7B overexpression had the opposite effect. An immunoprecipitation-mass spectrometry analysis showed that OTUD7B directly binds to KLF4 (Krüppel-like factor 4). Additional molecular experiments showed that OTUD7B impedes KLF4 degradation by inhibiting lysine residue at 48 site-linked ubiquitination and suppressing myocardial hypertrophy by activating the serine/threonine kinase pathway.

CONCLUSIONS

These results demonstrate that the OTUD7B-KLF4 axis is a novel molecular target for CH treatment.

Evaluating the Role of lncRNAs in the Incidence of Cardiovascular Diseases in Androgenetic Alopecia Patients

Hair loss occurs in patients with Androgenetic Alopecia (AGA). The pattern of hair loss is different between men and women. The main cause of hair loss is increased cell apoptosis and decreased regeneration, proliferation and differentiation processes in hair follicles. Long Non-Coding RNAs (lncRNAs) are one of the most important molecules that regulate the processes of apoptosis, regeneration, proliferation and differentiation in hair follicles. Since studies have shown that lncRNAs can be effective in the development of cardiotoxicity and induction of cardiovascular disease (CVD); so effective lncRNAs in the regulation of regeneration, proliferation, differentiation and apoptosis of hair follicles can be involved in the development of CVD in AGA patients with. Therefore, this study investigated the lncRNAs involved in increasing apoptosis and reducing the processes of regeneration, proliferation and differentiation of hair follicles. The aim of the current study was to evaluate the role of lncRNAs as a risk factor in the incidence of CVD in AGA patients; it will help to design treatment strategies by targeting signaling pathways without any cardiotoxicity complications.