Doxorubicin Incorporation into Gold Nanoparticles: An In Vivo Study of Its Effects on Cardiac Tissue in Rats

Gold nanoparticles (Au-NPs) have been explored as potential vectors for enhancing the antitumor efficacy of doxorubicin (DOX) while minimizing its cardiotoxic effects. However, the impacts of DOX Au-NPs on cardiac function and oxidative stress remain inadequately understood. This study aimed to explore the effects of DOX Au-NPs in comparison to free DOX, focusing on oxidative stress markers, inflammation, ultrastructural changes, and cardiac function. Male rats were divided into the following four groups: control, citrate Au-NPs, DOX, and DOX Au-NPs. Cardiac function was assessed using echocardiography, and oxidative stress was evaluated through Nrf2, malondialdehyde (MDA) and superoxide dismutase (SOD) levels, and the GSH/GSSG ratio. The ultrastructure of cardiac tissue was assessed by transmission electron microscopy (TEM). Rats treated with DOX Au-NPs exhibited significant cardiac dysfunction, as indicated by a reduction in fractional shortening and ejection fraction. Oxidative stress markers, including elevated MDA levels and a reduced GSH/GSSG ratio, were significantly worse in the DOX Au-NP group. SOD levels decreased, indicating compromised antioxidant defenses. Citrate Au-NPs also caused some alterations in cardiac function and ultrastructure but without other molecular alterations. DOX Au-NPs failed to mitigate cardiotoxicity, instead exacerbating oxidative stress and cardiac dysfunction. DOX Au-NPs possess cardiotoxic effects, necessitating further investigation into alternative nanoparticle formulations or therapeutic combinations to ensure both efficacy and safety in cancer treatment.