[Sinomenine ameliorates bleomycin A5-induced pulmonary fibrosis by blocking the miR-21/ADAMTS-1 signaling pathway in rats].

Objective To explore the impact of sinomenine on bleomycin A5-induced pulmonary fibrosis (PF) in rats and the underlying mechanism. Methods MRC-5 cells were cultured and treated with sinomenine to determine its optimal concentration and time through the MTT assay. Subsequently, MRC-5 cells were incubated with 80 µmol/L sinomenine for 48 hours or transfected with miR-21 mimic/a disintegrin-like and metalloproteinase with thrombospondin type 1 motif (ADAMTS-1) siRNA prior to sinomenine treatment. The expression of miR-21, ADAMTS-1, collagen type 1 (Col1) and collagen type 3 (Col3) was detected by quantitative real-time PCR (qRT-PCR) and/or Western blot analysis. Thirty SD rats were randomly divided into control group, sinomenine group and sinomenine combined with miR-21 agomir group, with 10 animals in each group. Bleomycin A5 were intratracheally administered to establish the PF model. Then, rats in control group, sinomenine group and sinomenine +miR-21 agomir group were treated with 9 g/L sodium chloride solution, sinomenine and sinomenine+miR-21 agomir, respectively. On day 28, all rats were sacrificed. HE and Masson staining was performed in pulmonary tissue. The expression of ADAMTS-1, Col1 and Col3 in pulmonary tissue were detected by qRT-PCR and/or Western blot analysis. ELISA was used to measure serum procollagen type 1 carboxyterminal propeptide (P1CP) and procollagen type 3 aminoterminal propeptide (P3NP) levels. Results Administration of sinomenine decreased miR-21 levels, up-regulated ADAMTS-1 expression, and promoted Col1 and Col3 degradation in MRC-5 cells. Importantly, interfering with the miR-21/ADAMTS-1 signaling pathway partially reversed the promotive effect of sinomenine on Col1 and Col3 degradation. Treatment of SD rats with sinomenine reduced alveolitis and PF scores, decreased serum P1CP and P3NP levels, up-regulated pulmonary ADAMTS-1 expression, and down-regulated Col1 and Col3 expression. However, these effects were reversed by miR-21 agomir. Conclusion Sinomenine promotes Col1 and Col3 degradation and inhibits PF in rats by miR-21/ADAMTS-1 pathway.

Upregulation of miR­335 exerts protective effects against sepsis­induced myocardial injury.

Septicemia is associated with excessive inflammation, oxidative stress and apoptosis, causing myocardial injury that results in high mortality and disability rates worldwide. The abnormal expression of multiple microRNAs (miRNAs/miRs) is associated with more severe sepsis­induced myocardial injury (SIMI) and miR­335 has been shown to protect cardiomyocytes from oxidative stress. The present study aimed to investigate the role of miR­335 in SIMI. An SIMI model was established by cecal ligation and puncture (CLP) in mice. An miRNA­335 precursor (pre­miR­335) was transfected to accelerate miR­335 expression and an miR­335 inhibitor (anti­miR­335) was used to inhibit miR­335 expression. CLP or sham surgery was performed on pre­miR­335, anti­miR­335 and wild­type mice and miR­335 expression was determined by reverse transcription­quantitative PCR. Inflammatory factors (TNF­α, IL­6 and IL­10) and troponin (cTNI), brain natriuretic peptide (BNP), creatine kinase (CK), lactate dehydrogenase (LDH) and aspartate aminotransferase (AST) were assessed using commercial kits. Apoptosis was detected by flow cytometry and cardiac function was assessed using a Langendorff isolated cardiac perfusion system. miR­335 expression was upregulated and an elevation in inflammatory factors and cTNI, BNP, CK, LDH and AST was observed. Compared with the wild­type control group, pre­miR­335 mice treated with CLP exhibited significantly reduced left ventricular development pressure, maximum pressure increased reduction rates, as well as decreased levels of TNF­α, IL­6 and IL­10, myocardial injury and apoptosis; by contrast, these features were amplified in CLP­treated anti­miR­335 mice. In conclusion, the upregulation of miR­335 exerted ameliorative effects on myocardial injury following sepsis and may indicate a novel therapeutic intervention for SIMI.