Chlorogenic acid protects against myocardial ischemia-reperfusion injury in mice by inhibiting Lnc Neat1/NLRP3 inflammasome-mediated pyroptosis.

Increasing evidences demonstrate that chlorogenic acid (CGA), a polyphenol with multiple effects such as anti-inflammatory and anti-oxidation, protects against myocardial ischemia-reperfusion injury (MIRI) in vitro and in vivo. But its detailed cardiac protection mechanism is still unclear. The MIRI mice model was established by ligating the left anterior descending branch (LAD) of the left coronary artery in C57BL/6 mice. Sixty C57BL/6 mice were randomly divided into four groups. CGA group and CGA + I/R group (each group n = 15) were gavaged with 30 mg/kg/day CGA for 4 weeks. Sham group and I/R group mice (each group n = 15) were administered equal volumes of saline. In vitro MIRI model was constructed by hypoxia and reoxygenation of HL-1 cardiomyocytes. The results showed that CGA pretreatment reduced myocardial infarction size and cTnT contents in serum, simultaneously reduced the levels of Lnc Neat1 expression and attenuated NLRP3 inflammasome-mediated pyroptosis in myocardial tissue. Consistent with in vivo results, the pretreatment of 0.2 µM and 2 µM CGA for 12 h in HL-1 cardiomyocytes depressed hypoxia/reoxygenation-induced Lnc Neat1 expression, NLRP3 inflammasome activation and pyroptosis. Lnc Neat1 shRNA transfection mediated by lentivirus in HL-1 cardiomyocytes significantly reduced activation of NLRP3 inflammasome and pyroptosis. Our findings suggest that CGA protects against MIRI by depressing Lnc Neat1 expression and NLRP3 inflammasome-mediated pyrotosis. Inhibiting the levels of Lnc Neat1 expression may be a therapeutic strategy for MIRI.

Prodigiosin inhibits cholangiocarcinoma cell proliferation and induces apoptosis via suppressing SNAREs-dependent autophagy.

BACKGROUND: Prodigiosin (PG), a natural red pigment produced by numerous bacterial species, has been a eye-catching research point in recent years for its anticancer activity. However, the role of PG in the cancer biology of cholangiocarcinoma (CCA) remains vague. METHODS: The proliferation of CCA cells was detected by Cell Counting Kit-8(CCK-8), Colony formation assay and 5-ethynyl-2'-deoxyuridine (EdU) assay. Cell apoptosis was evaluated by flow cytometry assay and western blot assay. The effects of PG or SNAREs on cell autophagy were measured by autophagy flux assay and western blot assay. Xenograft mouse models were used to assess the role of PG in CCA cells in vivo. RESULTS: PG could inhibit the proliferation and viability of CCA cells in a concentration- and time-dependent manner via suppressing the late stage of autophagy. Mechanistically, PG inhibits the fusion of autophagosomes and lysosomes by blocking STX17 and SNAP29, components of soluble N-ethyl-maleimide-sensitive factor attachment protein receptors (SNAREs)complex. When STX17 and SNAP29 were overexpressed, the inhibitory effect of PG on CCA cells autophagy was relieved. In addition, PG showed obvious inhibitory effects on cancer cell viability but no toxic effects on organs in xenotransplantation models. CONCLUSION: Taken together, our results demonstrated that PG inhibits CCA cell proliferation via suppressing SNAREs-dependent autophagy, implying that PG could be a potential chemotherapy drug for advanced CCA.

MicroRNA-138-5p regulates pancreatic cancer cell growth through targeting FOXC1.

PURPOSE: The prognosis of pancreatic cancer ranks among the worst of all cancer types, which is primarily due to the fact that during the past decades little progress has been made in its diagnosis and treatment. Here, we set out to investigate the role of microRNA 138 (miR-138-5p) in the regulation of pancreatic cancer cell growth and to assess its role as putative therapeutic target. METHODS: qRT-PCR was used to examine the expression of miR-138-5p in 8 pancreatic cancer cell lines and 18 primary human pancreatic cancer samples. A lentivirual vector containing miR-138-5p mimics (lv-miR-138-5p) was used to exogenously over-express miR-138-5p in the pancreatic cancer cells lines Capan-2 and PANC-1. The effect of this over-expression on cell proliferation was examined using an in vitro propidium iodide fluorescence assay. Capan-2 cells exogenously over-expressing miR-138-5p were transplanted into nude mice to examine its in vivo effect on tumor growth. A predicted target of miR-138-5p (FOXC1) was first validated using a luciferase assay and, subsequently, down-regulated by siRNA to assess its effect on pancreatic cancer cell growth. RESULTS: We found that miR-138-5p was markedly down-regulated in both pancreatic cancer cell lines and primary human pancreatic cancer samples, compared to a human pancreas ductal epithelial (HPDE) cell line and normal pancreatic tissues, respectively (P < 0.05). In addition, we found that in the pancreatic cancer cells lines Capan-2 and PANC-1 lentiviral transfection of miR-138-5p mimicked up-regulation of the endogenous expression of miR-138-5p and, concomitantly, inhibited cancer cell proliferation (P < 0.05). The exogenous over-expression of miR-138-5p also led to a significant inhibition of tumor formation in vivo. Using a luciferase assay, we found that miR-138-5p directly targets FOXC1. In conformity with this notion, we found that FOXC1 was down-regulated upon miR-138-5p over-expression in pancreatic cancer cells. Finally, we found that silencing of FOXC1 by siRNA had an inhibitory effect on pancreatic cancer cell growth. CONCLUSIONS: Our data indicate that miR-138-5p may play an important role in regulating pancreatic cancer cell growth, possibly through targeting FOXC1. Over-expression of miR-138-5p may serve as a novel approach for the treatment of patients with pancreatic cancer.