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Background MicroRNAs (miRNAs) are a novel class of powerful, endogenous regulators of gene expression. This study was designed to ascertain if miR-30a is involved in the cardioprotective actions of salvianolic acid B (Sal B) against myocardial ischemia–reperfusion (I–R) injury through suppression of autophagy. Methods Murine myocardial cells that had undergone primary culture were induced by I–R and incubated with Sal B (25, 50, 100 μM) in the presence of a miR-30a mimic or miR-30a inhibitor. Expression of miR-30a, beclin-1, LC3-II and p-Akt protein, cell viability, and lactic acid dehydrogenase (LDH) release were assessed. Results miR-30a expression was down-regulated remarkably in I–R cells, and this suppression could be reversed by Sal B in a dose-dependent manner. Sal B repressed autophagy in I–R myocardial cells. Sal B improved cell viability and reduced the rate of LDH leakage, which suggested that autophagy suppression was beneficial for cell survival. Knockdown of miR-30a with a miR-30a inhibitor could reverse the anti-autophagy effect of Sal B against I–R injury. Furthermore, we confirmed that Sal B has a protective role in miR-30a-mediated autophagy through the PI3K/Akt signaling pathway, which was abrogated by the PI3K inhibitor LY294002. Conclusions These data suggest that miR-30a is involved in Sal B-mediated cardioprotection against I–R injury through the PI3K/Akt signaling pathway. Electronic supplementary material The online version of this article (doi:10.1186/s12906-016-1275-x) contains supplementary material, which is available to authorized users.

Background Autophagy can result in cellular adaptation, as well as cell survival or cell death. We investigated how ginsenoside Rg1(G-Rg1) regulates the relationship between autophagy and apoptosis induced by continuous starvation. Methods H9c2 cells under continuous starvation were treated with or without ginsenoside Rg1, and autophagy and apoptosis related proteins were assessed over a continuous time course by Western blot. Dynamic fluorescence intensity of green fluorescent protein (GFP)-LC3 was used to assess autophagosome formation by live cell imaging. Cyan fluorescent protein (CFP) -Beclin1(BECN1) and yellow fluorescent protein (YFP) -Bcl-2 were co-transfected into cells to observe ginsenoside Rg1 regulation of BECN1/Bcl-2 interaction using Fluorescence Resonance Energy Transfer (FRET). Immunoprecipitation was also used to assess BECN1/Bcl-2 interaction over a continuous time course. Results In H9c2 cells, starvation induced both apoptosis and autophagy. Cell apoptosis was significantly attenuated in ginsenoside Rg1-treated conditions, while autophagy was promoted. Ginsenoside Rg1 weakened the interaction between Beclin1 and Bcl-2, inhibiting apoptosis while promoting autophagy. Our results suggest that autophagy is beneficial to starved cardiac cells over a period of time. Furthermore, we describe the effect of ginsenoside Rg1 on the relationship between autophagy and apoptosis during starvation. Conclusions Our findings provide valuable evidence for employing ginsenoside Rg1 as a specific promoter of autophagy and inhibitor of apoptosis. Electronic supplementary material The online version of this article (doi:10.1186/s12906-016-1112-2) contains supplementary material, which is available to authorized users.

Background TRPV6 is over-expressed and promotes the proliferation and invasion in many cancers. The association between the expression of TRPV6 and clinical outcome in esophageal squamous cell carcinoma (ESCC) has not been studied yet. We aim to elucidate the role of TRPV6 in predicting prognosis of patients with ESCC. Methods In the retrospective study, mRNA level of TRPV6 was examined in patients (N = 174) from Sun Yat-sen University Cancer Center (mRNA cohort) and protein level of TRPV6 was examined in patients (N = 218) from Linzhou Cancer Hospital (protein cohort). Statistical analysis was performed to test the clinical and prognostic significance of TRPV6. Results TRPV6 was down-regulated in ESCC tissues and cell lines. Patients with downregulation of TRPV6 trended to have a higher rate of advanced pT stage in both mRNA cohort (P = 0.089) and protein cohort (P = 0.073), though not statistically significant. No significant association was observed between TRPV6 expression and disease-specific survival (DSS) in both two cohorts. However, stratified survival analysis based on the gender showed that in mRNA cohort, downregulation of TRPV6 was associated with an unfavorable 3-year DSS in patients with male (47.3 % vs 63.6 %, P = 0.027) and with favorable 3-year DSS in patients with female (66.7 % vs 43.0 %, P = 0.031). The result was confirmed in protein cohort. Male patients with downregulation of TRPV6 had a poor 3-year DSS (20.0 % vs 57.1 %,P

Background The correlation of S-phase kinase–associated protein 2 (Skp2) with metastasis and prognosis in esophageal squamous cell carcinoma (ESCC) is controversial. The purpose of this study was to explore whether there was a correlation between the expression of Skp2 evaluated by immunohistochemistry and the clinical outcome of patients with operable ESCC, and to further determine the possible mechanism of the impact of Skp2 on survival. Methods Tissue microarrays that included 157 surgically resected ESCC specimens was successfully generated for immunohistochemical evaluation. The clinical/prognostic significance of Skp2 expression was analyzed. Kaplan-Meier analysis was used to compare the postoperative survival between groups. The prognostic impact of clinicopathologic variables and Skp2 expression was evaluated using a Cox proportional hazards model. A cell proliferation assay and a colony formation assay were performed in ESCC cell lines to determine the function of Skp2 on the progression of ESCC in vitro. Results Skp2 expression correlated closely with the T category (p = 0.035) and the pathological tumor-node-metastasis (TNM) stage (p = 0.027). High expression of Skp2 was associated with poor overall survival in resectable ESCC (p = 0.01). The multivariate Cox regression analysis demonstrated that pathological T category, pathological N category, cell differentiation, and negative Skp2 expression were independent factors for better overall survival. In vitro assays of ESCC cell lines demonstrated that Skp2 promoted the proliferative and colony-forming capacity of ESCCs. Conclusions Negative Skp2 expression in primary resected ESCC is an independent factor for better survival. Skp2 may play a pro-proliferative role in ESCC cells.