GLP-1 Receptor Agonist Exenatide Protects Against Doxorubicin-Induced Cardiotoxicity Through the SIRT1 Pathway: An Electrocardiographic, 99mTc-PYP Scintigraphic, and Biochemical Study

Background and Objectives: This study was designed to evaluate the potential cardioprotective effect of Exenatide against doxorubicin (DOX)-induced myocardial injury in rats by assessing scintigraphic alterations together with oxidative stress and inflammation. Materials and Methods: This study included 28 adult male Wistar albino rats that were randomized to 4 groups (n = 7): control, Exenatide alone, DOX (receiving DOX (18 mg/kg, i.p) on days 5–7; Exenatide + DOX (treated with Exenatide together with the DOX). On day 8, ECG, 99mTc-PYP scintigraphy, and biochemical parameters were evaluated. Results: DOX caused ECG abnormalities—bradycardia, significant QT prolongation, and elevated ST-segment amplitude—along with increased myocardial PYP uptake. Exenatide + DOX group significantly improved ECG changes. Biochemically, DOX markedly increased cardiac injury biomarkers (cTnT, CK, CK-MB), hepatic and renal injury markers (ALT, AST, LDH, BUN, creatinine), SIRT-1 level, inflammatory marker (NF-κB, TNF-α, IL-6, NO) and oxidative stress indicators (MDA, TOS), while decreasing antioxidant defenses (GSH, TAS, Nrf2). Exenatide co-treatment significantly attenuated all DOX-induced changes. Conclusions: Exenatide markedly attenuates DOX-induced cardiotoxicity by improving electrical conduction, reducing myocardial radiotracer uptake, and restoring oxidative–inflammatory balance through partial recovery of the SIRT-1/Nrf2/NF-κB pathway.