Objective To investigate the role of nicorandil pretreatment on protecting myocardium after coronary microembolization (CME) and on the PDCD4/NF-κB/TNF-α signaling pathway in miniature pigs. Methods Fifteen Bama miniature pigs were randomly(random number) divided into the sham operation group (sham group), microembolization group (CME group) and CME plus nicorandil group, with 5 pigs in each group. The CME model was constructed by injecting polyethylene microspheres via microcatheter into the left anterior descending artery, and pigs in the sham group were injected with the same amount of saline. Pigs in the CME plus nicorandil group were injected intravenously with nicorandil (150 μg/kg) via ear vein 30 min before CME. Cardiac function indexes were measured using cardiac ultrasonography. The expression of PDCD4 and TNF-α mRNA in myocardium were detected by fluorescence quantitative PCR, and the protein expression of PDCD4 and TNF-α in myocardium were detected by Western blotting. NF-κB activation was evaluated by electrophoretic mobility shift assay. Results (1) Cardiac function was significantly lower and the level of serum cTnI was significantly higher in the CME group compared with the sham group. CME reduced myocardial systolic dysfunction and left ventricular dilatation. The CME plus nicorandil group showed improved CME-induced cardiac function and reduced serum cTnI level when compared with the CME Group (P < 0.05). (2) Compared with the CME group, the CME plus nicorandil group showed lower PDCD4 and TNF-α expression and NF-κB activity as well as improved cardiac function (P < 0.05). Conclusions The pretreatment of nicorandil effectively reduced the myocardial damage caused by CME, mainly through inhibiting the PDCD4/NF-κB/TNF-α pathway in cardiomyocytes.

Inflammatory bowel disease(IBD)is a chronic intestinal disorder characterized by an immune response to factors in the intestinal environment.Dysregulation of the gut microflora(GM)may lead to inflammation.Studies suggest that fecal microbiota transplantation,probiotics,prebiotics,and dietary treatments may reshape the GM and treat the disease.MicroRNAs(miRNAs)participate in physiological processes,including cell development,proliferation,and apoptosis.Additionally,miRNAs are important for inflammatory processes and play a role in regulating pro-and anti-inflammatory pathways.MiRNA profiles may serve as diagnostic and prognostic markers for IBD.The relationship between miRNAs and GM has not been fully elucidated,and recent studies have demonstrated their roles in regulating GM and inducing ecological dysbiosis.In turn,GM regulates miRNA expression and improves intestinal homeostasis.It is important to continue exploring this relationship.Therefore,the purpose of this review is to analyze the relationship between gut microbiota and miRNAs in IBD and identify possible precision-targeted therapies for IBD.