miR‑320a in serum exosomes promotes myocardial fibroblast proliferation via regulating the PIK3CA/Akt/mTOR signaling pathway in HEH2 cells

MicroRNAs (miRNAs/miRs) serve an important role in the pathogenesis of chronic heart failure (CHF). A number reports have illustrated regulatory effect serum exosomal miRNA on myocardial fibrosis. The present study aimed to investigate expression miR‑320a exosomes, as well fibroblast proliferation. Serum exosome samples from 10 patients with CHF and 5 healthy volunteers were obtained characterized. mRNA protein levels measured via reverse transcription‑quantitative PCR western blotting, respectively. content soluble growth stimulation expressed gene 2 (sST2) was determined ELISA. HEH2 cell viability apoptosis detected by performing MTT assays flow cytometry, results demonstrated that sST2 significantly increased compared controls, correlated clinical indexes. exosomes isolated those controls. Phosphoinositide‑3‑kinase catalytic α polypeptide (PIK3CA) cells following transfection mimics NC‑mimic, whereas inhibitor displayed contrasting effects reduced fibroblasts NC‑inhibitor group. collagen I, III, α‑smooth muscle actin, phosphorylated (p)‑mTOR (ser 2448)/mTOR, p‑Akt 473)/Akt, (thr 308)/Akt PIK3CA mimic‑transfected NC‑mimics groups. By contrast, notably downregulated these proteins Collectively, promoted proliferation regulating PIK3CA/Akt/mTOR signaling pathway cells, suggesting may a potential biomarker for diagnosis CHF.