Fig. 6: Exosomal miR-182-5p from MSCs inhibits inflammation and pyroptosis of H/R-exposed myocardial cells via inhibition of GSDMD.

H/R-exposed myocardial cells were co-cultured with MSC-derived exosomes or not. GSDMD expression was silenced in H/R-exposed myocardial cells while miR-182-5p expression was altered in MSC-derived exosomes using mimics or inhibitors before co-culture. A miR-182-5p expression and GSDMD mRNA level in H/R-exposed myocardial cells detected by RT-qPCR, normalized to U6 and GAPDH, respectively; B Western blot analysis of GSDMD protein and GSDMD N in H/R-exposed myocardial cells, normalized to GAPDH; C The levels of IL-1β and IL-18 in the supernatant of H/R-exposed myocardial cells determined by ELISA; D The viability of H/R-exposed myocardial cells assessed by Calcein-AM/PI double staining; E The survival rate of H/R-exposed myocardial cells measured by trypan blue staining; F LDH release in H/R-exposed myocardial cells detected by LDH kit; G ROS production in H/R-exposed myocardial cells examined by DCFH-DA; H Western blot analysis of ASC, pro-caspase-1, and caspase-1 proteins as well as the cleaved caspase-1/pro-caspase-1 ratio in H/R-exposed myocardial cells, normalized to GAPDH. Measurement data were expressed as mean ± standard deviation. The comparison among multiple groups was conducted with one-way ANOVA, followed by Tukey’s post hoc test. Each cell experiment was repeated three times independently. *P < 0.05 vs. H/R-exposed myocardial cells without transfection, #P < 0.05 vs. H/R-exposed myocardial cells transfected with sh-NC and co-cultured with exosomes, &P < 0.05 vs. H/R-exposed myocardial cells co-cultured with exo-mimic-NC, @P < 0.05 vs. H/R-exposed myocardial cells co-cultured with exo-inhibitor-NC, ^P < 0.05 vs. H/R-exposed myocardial cells transfected with sh-GSDMD.