BACKGROUND:Our previous work has demonstrated that bone marrow mesenchymal stem cels (BMSCs) transplantation can improve the heart function of rats with myocardial infarction. However, the overal efficacy is not satisfactory. OBJECTIVE: To adopt pioglitazone as a peroxisome proliferator-activated receptor gamma (PPAR-γ) agonist combined with BMSCs transplantation therapy, thereby further improving cardiac function of rats with myocardial infarction as wel as investigating the relevant mechanisms. METHODS:Twenty Sprague-Dawley rats with myocardial infarction were induced by the left anterior descending coronary artery ligation. The animals were randomized into two groups: BMSCs and BMSCs+pioglitazone. Two weeks later, al the animals received the injection of BMSCs labeled with PKH26 in PBS into the local infarct zone, and then pioglitazone (3 mg/kg/d) was given by the oral gavage for 2 weeks in the BMSCs+pioglitazone group after the cel transplantation. After 2 weeks of cel transplantation, cardiac functions were evaluated by echocardiography. The expressions of PPAR-γ, Connexin 43 and molecules in TGF-β1/SMAD signaling pathway were examined in different areas of the left ventricle from each harvested heart using immunofluorescent staining, western blot assay and qRT-PCR. RESULTS AND CONCLUSION:There were no differences in the baseline parameters of cardiac function between the two groups. At 2 weeks after cel transplantation, the left ventricular internal diameter at end-diastole, left ventricular internal diameter at end-systole and left ventricular ejection fraction were significantly improved in the BMSCs+ pioglitazone group; the expressions of PPAR-γ and Connexin 43 were distinctly increased in different zones of the left ventricle; the levels of TGF-β1, SMAD2 and SMAD3 were obviously attenuated in the infarct zone and border zone. The above-mentioned findings suggest that pioglitazone, a PPAR-γ agonist, can enhance BMSCs potential in improvingthe heart function after myocardial infarction, and PPAR-γ may elevate the expression of Connexin 43via the blockade of the TGF-β1/SMAD signaling pathway in the procedure.

Increased intestinal barrier permeability, leaky gut, has been reported in patients with autism. However, its contribution to the development of autism has not been determined. We selected dextran sulfate sodium (DSS) to disrupt and metformin to repair the intestinal barrier in BTBR T⁺tf/J autistic mice to test this hypothesis. DSS treatment resulted in a decreased affinity for social proximity; however, autistic behaviors in mice were improved after the administration of metformin. We found an increased affinity for social proximity/social memory and decreased repetitive and anxiety-related behaviors. The concentration of lipopolysaccharides in blood decreased after the administration of metformin. The expression levels of the key molecules in the toll-like receptor 4 (TLR4)-myeloid differentiation factor 88 (MyD88)-nuclear factor kappa B (NF-κB) pathway and their downstream inflammatory cytokines in the cerebral cortex were both repressed. Thus, "leaky gut" could be a trigger for the development of autism via activation of the lipopolysaccharide-mediated TLR4-MyD88-NF-κB pathway.
Mice ; Animals ; NF-kappa B ; Myeloid Differentiation Factor 88/metabolism* ; Lipopolysaccharides/pharmacology* ; Toll-Like Receptor 4/metabolism* ; Autistic Disorder/metabolism* ; Signal Transduction/physiology*