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Background/Aims: Studies have demonstrated that 2-dodecyl-6-methoxycyclohexa-2, 5-diene-1, 4-dione (DMDD), isolated from the roots of Averrhoa carambola L., has significant therapeutic potential for the treatment of diabetes. However, the protective effect of DMDD against pancreatic beta cell dysfunction has never been reported. We investigated whether DMDD protected against palmitic acid-induced dysfunction in pancreatic β-cell line Min6 cells by attenuating the inflammatory response and apoptosis and to shed light on its possible mechanism. Methods: Cell viability was assessed by CCK-8. Glucose-stimulated insulin secretion levels and inflammatory cytokines levels were examined by ELISA. Apoptosis was assessed by Annexin V-FITC/PI Flow cytometry assay, Hoechst 33342/PI double-staining assay, and Transmission electron microscopy assay. Relative quantitative real-time PCR and western blot were used to determine the expressions of genes and proteins. Results: Cell viability and glucose-stimulated insulin secretion levels were increased in DMDD-pretreated Min6 cells. DMDD inhibited inflammatory cytokines IL-6, TNF-α and MCP-1 generations in palmitic acid (PA)-induced Min6 cells. Moreover, DMDD protected against PA-induced Min6 cells apoptosis and the expression of Cleaved-Caspase-3, -8 and -9 were down-regulated and the Bcl-2/Bax ratio was increased in DMDD-pretreated Min6 cells. In addition, the expression of TLR4, MyD88 and NF-κB were down-regulated in DMDD-pretreated Min6 cells and TAK-242-pretreated group cells. Conclusions: DMDD protected Min6 cells against PA-induced dysfunction by attenuating the inflammatory response and apoptosis, and its mechanism of this protection was associated with inhibiting the TLR4-MyD88-NF-κB signaling pathway.

Aim: The primary objective of this study was to study the effects of 17-methoxyl-7-hydroxy-benzene-furanchalcone (MHBFC) on pressure overload-induced cardiac remodeling in rats, as well as the endothelial mechanisms based on PGI2. Methods: Six weeks following surgery, rats were divided randomly into the following groups: a sham group, a model group, an MHBFC 12 mg/kg/day group (MHBFC 12), an indomethacin 2 mg/kg/day group (Indo 2), and an Indo 2+ MHBFC 12 group. The MS 4000 organism signal system was used to record the rats' hemodynamic indices. Additionally, the heart weight was determined, and the cardiac remodeling index was calculated. HE and Masson's stains were utilized to perform histological analyses; the immunofluorescence was used to observe the microvessel density of myocardial tissue; the colorimetric method was used to determine the hydroxyproline content of cardiac tissue; the ELISA method was used to measure the plasma PGI2 content; and transmission electron microscopy was used to observe the ultrastructure of the myocardium. Results: A hyperdynamic circulation state, cardiac remodeling, decreased microvessel density and decreased plasma PGI2 content were each observed in the model group compared with the sham group, in which any changes in the above parameters were effectively reversed by MHBFC. Single-use Indo administration resulted in the progression of these pathophysiological changes; however, MHBFC prevented the worsening of these parameters. Conclusion: MHBFC significantly reverses pressure overload-induced cardiac remodeling, and its mechanism may partially contribute to the amelioration of endothelial cell function and the augmentation of PGI2 synthesis and secretion.

Aims: Effect and mechanism of Yulangsan flavonoid (YLSF) on rat myocardial ischemia/reperfusion injury (MI/RI) has been investigated. Methods: Sprague-Dawley (SD) rats were randomly divided into seven groups (sham group, model group and NS group: 2 mL of normal saline/kg body weight was administered; diltiazem group: 5 mg of diltiazem hydrochloride/kg body weight was administered; YLSFL, YLSFM and YLSFH groups: 20, 40 and 80 mg of YLSF/kg body weight was administered) and the MI/RI model was established. Myocardial infarct area, levels of myocardial enzymes and nitric oxide synthase (NOS) were measured. Caspase-3 and adenine nucleotide translocator-1 (ANT1) mRNA expression were evaluated by reverse transcription polymerase chain reaction (RT-PCR). Pathological structure and cardiocyte ultrastructure were also analysed. Results: Compared with the MI/RI group, pretreatment with YLSF or diltiazem hydrochloride decreased the infarct area, levels of inducible nitric oxide synthase (iNOS), caspase-3 as well as the leakage of myocardial enzyme and increased activities of total nitric oxide synthase (tNOS) as well as constitutive nitric oxide synthase (cNOS). Cellular edema and the infiltration of inflammatory cells were alleviated. Conclusions: The experiment showed that YLSF protected the heart against MI/RI, possibly by reducing lipid peroxidation damage, regulating NOS activity and modulating the apoptosis genes expression.