Modulatory Effect of Nimbin on Isoproterenol Induced Mitochondrial and Lysosomal Enzymes Activities and Apoptosis Signaling in Rats

Nimbin, a bioactive triterpenoid compound isolated from the neem tree (Azadirachta indica), is known for its anti-inflammatory, antioxidant, antimicrobial, and hepatoprotective properties. The study aimed to explore the impact of nimbin on cardiac markers, mitochondrial and lysosomal enzyme activities, as well as apoptotic signaling in rats induced with isoproterenol. The subcutaneous injection of isoproterenol (ISO) at a dosage of 85 mg/kg body weight over the last two consecutive days led to notable increased in the activities/levels of the cardiac markers, lysosomal glycohydrolases and cathepsins. Conversely, reductions in the functioning of mitochondrial tricarboxylic acid cycle enzymes and respiratory chain enzymes in ISO-induced rats. In ISO-induced rats, there was an augmentation in the expressions of Bax, caspase-3, caspase-9, and cytochrome c, along with a diminished level of Bcl-2. Administration of nimbin resulted in decreased activities/levels cardiac markers, lysosomal glycohydrolases, cathepsins and increased functioning of mitochondrial tricarboxylic acid cycle enzymes and respiratory chain enzymes. Additionally, decreased expressions of Bax, executioner caspases and cytochrome c, along with heightened expression of Bcl-2, were noted in rats treated with nimbin. This indicates that nimbin possesses cardioprotective properties and mitigates mitochondrial and lysosomal dysfunction in rats induced with ISO. Key words Myocardial infarction " Tricarboxylic acid (TCA) cycle enzymes " Cathepsin-D " Cardiac markers " Triterpenoid.