Extracellular vesicles from adipose-derived stem cell alleviate diabetic cardiomyopathy by regulating Chit1/NLRP3/Caspase-1-Mediated pyroptosis.

It is well-established that chronic hyperglycemia progressively destroys the heart structure, weakening function and leading to diabetic cardiomyopathy (DCM). Extracellular vesicles derived from adipose-derived stem cell (ADSC-EVs) have been reported to have anti-inflammatory and immune-modulating effects, but their role in DCM is still poorly understood. Therefore, this study investigated the impact of ADSC-EVs on DCM and potential mechanisms. ADSC-EVs were isolated from the conditioned media of ADSCs. DCM rat models were established using streptozotocin (STZ) in vivo, and high glucose (HG) stimulated H9c2 cardiomyocytes to establish in vitro model. Then mRNA sequencing identified Chit1 as a key gene. Both in vivo and in vitro experiments demonstrated that chitinase 1 (Chit1) and NLRP3/Caspase-1-mediated pyroptosis levels were significantly upregulated in myocardial tissue of rat diabetic cardiomyopathy and hyperglycemic cardiomyocytes, which was reversed by ADSC-EVs treatment. We next observed that in hyperglycemic cardiomyocytes, downregulating Chit1 also resulted in a decrease in NLRP3/Caspase-1-mediated pyroptosis proteins. To a certain extent, the inhibitory effect of ADSC-EVs on the NLRP3/Caspase-1 signaling pathway was reversed by Chit1 overexpression. Taken together, we identified a novel mechanism by which ADSC-EVs regulate NLRP3/Caspase-1-mediated pyroptosis through Chit1 to alleviate diabetic cardiomyopathy, offering an innovative strategy for DCM treatment.