Astragaloside IV Inhibits NLRP3 Inflammasome-Mediated Pyroptosis via Activation of Nrf-2/HO-1 Signaling Pathway and Protects against Doxorubicin-Induced Cardiac Dysfunction.

BACKGROUND

Doxorubicin (DOX) is an effective broad-spectrum antitumor drug, but its clinical application is limited due to the side effects of cardiac damage. Astragaloside IV (AS-IV) is a significant active component of that exerts cardioprotective effects through various pathways. However, whether AS-IV exerts protective effects against DOX-induced myocardial injury by regulating the pyroptosis is still unknown and is investigated in this study.

METHODS

The myocardial injury model was constructed by intraperitoneal injection of DOX, and AS-IV was administered via oral gavage to explore its specific protective mechanism. Cardiac function and cardiac injury indicators, including lactate dehydrogenase (LDH), cardiac troponin I (cTnI), creatine kinase isoenzyme (CK-MB), and brain natriuretic peptide (BNP), and histopathology of the cardiomyocytes were assessed 4 weeks post DOX challenge. Serum levels of IL-1β, IL-18, superoxide dismutase (SOD), malondialdehyde (MDA) and glutathione (GSH) and the expression of pyroptosis and signaling proteins were also determined.

RESULTS

Cardiac dysfunction was observed after the DOX challenge, as evidenced by reduced ejection fraction, increased myocardial fibrosis, and increased BNP, LDH, cTnI, and CK-MB levels ( < 0.05, N = 3-10). AS-IV attenuated DOX-induced myocardial injury. The mitochondrial morphology and structure were also significantly damaged after DOX treatment, and these changes were restored after AS-IV treatment. DOX induced an increase in the serum levels of IL-1β, IL-18, SOD, MDA and GSH as well as an increase in the expression of pyroptosis-related proteins ( < 0.05, N = 3-6). Besides, AS-IV depressed myocardial inflammatory-related pyroptosis via activation of the expressions of nuclear factor E2-related factor 2 (Nrf-2) and heme oxygenase 1 (HO-1) ( < 0.05, N = 3).

CONCLUSIONS

Our results showed that AS-IV had a significant protective effect against DOX-induced myocardial injury, which may be associated with the activation of Nrf-2/HO-1 to inhibit pyroptosis.