AIM To investigate the effect of semaglutide on pyroptosis of AC16 human cardiomyocytes after hypoxia-reoxygenation (H/R) injury through both classical and non-classical pathways.

METHODS AC16 cells in logarithmic growth phase were randomized into three groups: control group, H/R model group, and H/R + semaglutide group. Except for the control group, cells in the other two groups underwent 8 hours of hypoxia followed by 12 hours of reoxygenation. Cell viability was assessed using CCK-8 kits, IL-18 levels were measured by ELISA kits, cell damage was evaluated using LDH kits, and the protein expressions of Caspase-1, Caspase-4, GSDMD and NLRP3 were analyzed by Western blot. The positive expression of GSDMD in each group of cells was observed through immunofluorescence staining. The cell membrane structure impairment of AC16 cells was observed by transmission electron microscopy.

RESULTS Compared with the control group, the levels of IL-1β, IL-18 and LDH in the H/R group were significantly increased (P<0.01), the expressions of pyroptosis-related proteins including Caspase-1, Caspase-4, GSDMD and NLRP3 were obviously increased (all P<0.01), and the fluorescence intensity of GSDMD was significantly increased (P<0.01). Compared with the H/R group, the levels of IL-1β, IL-18 and LDH in the H/R + semaglutide group were significantly decreased (all P<0.01), the expressions of Caspase-1, Caspase-4, GSDMD, and NLRP3 were significantly decreased (all P<0.01), and the fluorescence intensity of GSDMD was significantly decreased (P<0.01).

CONCLUSIONS Semaglutide inhibits both the classical and non-classical pathways of pyroptosis by suppressing Caspase-1 and Caspase-4, thus preventing cardiomyocyte pyroptosis, reducing the release of inflammatory factors, alleviating myocardial inflammatory injury, and protecting the cardiomyocytes.