miR-135a Mediates Mitochondrial Oxidative Respiratory Function through SIRT1 to Regulate Atrial Fibrosis.

INTRODUCTION: This study aimed to explore the function of miR-135a in the progress of atrial fibrosis and the mechanism of miR-135a/SIRT1 (sirtuin 1) in human cardiac fibroblasts and mouse cardiac fibroblasts (MCFs) mediating the regulation of atrial fibrosis by mitochondrial oxidative respiration function. METHODS: Using Ang II (angiotensin II) to induce fibrosis in HCFs (human corneal fibroblasts) and MCF (Michigan Cancer Foundation, MCF) cells in vitro, the miRNA-seq results of previous studies were validated. Proliferative and invasive ability of HCFs and MCFs was detected by Cell Counting Kit-8 assay (CCK-8) and scratch experiment after overexpressing miR-135a in HCFs and MCF cells. Protein and mRNA expression was tested using Western blot and qPCR. The target of miR-135a was verified as SIRT1 by a luciferase reporter assay and the activities of the mitochondrial respiratory enzyme complexes I, II, III, and IV were determined colorimetrically. The activities of malondialdehyde, reactive oxygen species, and superoxide dismutase in cells were detected with enzyme-linked immunosorbent assay (ELISA). RESULTS: miR-135a expression was elevated in HCFs and MCFs cells in the Ang II group than control group. Overexpression of miR-135a could promote the proliferation, migration, oxidative stress, as well as fibrosis of cardiac fibroblasts and suppresses mitochondrial activity. In addition, we found SIRT1 was a target gene of miR-135a. What is more, the findings showed miR-135a promoted fibrosis in HCFs and MCFs cells acting through regulation of SIRT1. CONCLUSIONS: miR-135a mediates mitochondrial oxidative respiratory function through SIRT1 to regulate atrial fibrosis.

Tests and analyses on physical and mechanical properties of fresh black fungus in picking season.

This study determined the physical and mechanical characteristics of fresh black fungus during the harvesting season to provide basic data for the development of mechanical equipment for black fungus harvesting and processing. We have conducted a comprehensive test of black fungus cultivars "Heishan". The mono-factor separation force experiments of black fungus and black fungus virgulate medium were conducted. It was noted that the tension angle was an important factor affecting the separation force, which was mainly distributed between 1.06 and 3.65 N. Besides, the average value of Poisson's ratio of black fungus was measured to be 0.445 in the tensile test of black fungus leaves using image recognition and analysis techniques, with a test error within 2.5%; and the average value of tensile elastic modulus and shear elastic modulus of black fungus leaves was 0.947 MPa and 0.327 MPa, respectively; we also found that the average tensile strength at the root of black fungus was not significantly different from that at the leaf, which was around 0.436 MPa. In addition, it was obtained that the height and thickness dimensions of black fungus in the picking season conformed to a normal distribution, and concentrated around 34.39mm and 0.92mm respectively.