NMMHC IIA Inhibition Ameliorates Cerebral Ischemic/Reperfusion-Induced Neuronal Apoptosis Through Caspase-3/ROCK1/MLC Pathway.

PURPOSE: Our previous studies have indicated that non-muscle myosin heavy chain IIA (NMMHC IIA) is involved in H2O2-induced neuronal apoptosis, which is associated with the positive feedback loop of caspase-3/ROCK1/MLC pathway. However, the neuroprotective effect of NMMHC IIA inhibition with an adeno-associated virus (AAV) vector after transient middle cerebral artery occlusion (MCAO) and its role in caspases-3/ROCK1/MLC pathway remain blurred. METHODS: Green fluorescent protein (GFP) and a small hairpin RNA targeting Myh9 (encoding NMMHC IIA) were cloned and packaged into the AAV9 vector. AAV-shMyh9 or control vector were injected into C57BL/6J mice four weeks prior to 60 min MCAO. Twenty-four hours after reperfusion, functional and histological analyses of the mice were performed. RESULTS: In this study, AAV-shMyh9 was used to down-regulate NMMHC IIA expression in mice. We found that down-regulation of NMMHC IIA could improve neurological scores and histological injury in ischemic mice. Ischemic attack also activated neuronal apoptosis, and this effect was partially attenuated when NMMHC IIA was inhibited by AAV-shMyh9. In addition, AAV-shMyh9 significantly reduced cerebral ischemic/reperfusion (I/R)-induced NMMHC IIA-actin interaction, caspase-3 cleavage, Rho-associated kinase1 (ROCK1) activation and myosin light-chains (MLC) phosphorylation. CONCLUSION: Consequently, we showed that AAV-shMyh9 inhibits I/R-induced neuronal apoptosis linked with caspase-3/ROCK1/MLC/NMMHC IIA-actin cascade, which has also been confirmed to be a positive feedback loop. These findings put some insights into the neuroprotective effect of AAV-shMyh9 associated with the regulation of NMMHC IIA-related pathway under ischemic attack and provide a therapeutic strategy for ischemic stroke.

Plasma microRNA: A novel non-invasive biomarker for HBV-associated liver fibrosis staging.

The aim of the present study was to evaluate the potential use of 7 plasma miRNAs for liver fibrosis staging in patients with chronic hepatitis B virus (HBV) infection. Relative levels of miRNAs were measured using quantitative polymerase chain reaction and used to develop a diagnostic panel. A receiver operating characteristic (ROC) curve was drawn to evaluate the performance of individual miRNAs and the whole panel. It was identified that hsa-miR-122 exhibited significantly different expression levels between F4 and F3, F2, F1, and F0 fibrosis stages (P<0.05), and between F2 and F1 stages (P=0.045); hsa-miR-146a-5p, hsa-miR-29c-3p and hsa-miR-223 exhibited significantly different expression levels between F4 and F0 stages. ROC analysis revealed that hsa-miR-122-5p, hsa-miR-223 and hsa-miR-29c-3p identified patients with ≥F2 fibrosis with area under the curve (AUC) =0.745, 0.631 and 0.670, respectively. hsa-miR-122-5p identified patients with ≥F3 disease (AUC=0.783). hsa-miR-122-5p, hsa-miR-223 and hsa-miR-29c-3p identified patients with cirrhosis with AUC=0.776, 0.617 and 0.619, respectively. The miRNA panel exhibited a higher accuracy compared with individual miRNAs in discriminating between ≥F2, ≥F3 and F4 fibrosis stages with AUC=0.904, 0.889 and 0.835, respectively. hsa-miR-122-5p, hsa-miR-146a, hsa-miR-29c and hsa-miR-223 were positively correlated with fibrosis stage. hsa-miR-122-5p and hsa-miR-381-3p were negatively correlated with alanine aminotransferase, aspartate transaminase and HBV viral DNA load. These 7 miRNAs may serve as potential biomarkers of liver fibrosis in patients with HBV-associated fibrosis. The miRNA panel may serve as a novel non-invasive method for liver fibrosis staging.