Ischemia/reperfusion (I/R) injury results in cell death by inducing apoptosis. During I/R, early generation of mitochondrial reactive oxygen species (mtROS) can induce neighboring mitochondria to release additional ROS, a toxic cycle resulting in significant mitochondrial and cellular injury. Oxidative damage in the mitochondria contributes to various pathologies, including I/R injury. Accordingly, preventing mitochondrial oxidative damage should be therapeutically relevant for many disorders, including cardiovascular diseases. We recently discovered an Indole-Peptide-Tempo Conjugate (IPTC) that served as a novel bifunctional agent with both antioxidant and autophagy-modulating capacity. Here, we demonstrate that IPTC can protect H9C2 cardiomyocytes from hypoxia/reoxygenation (H/R) injury that results from mtROS overproduction due to impaired mitophagy and resultant mitochondrial dysfunction. We hypothesize that the mechanism of action of IPTC involves the capacity to decrease mtROS combined with induction of mitophagy.

Puerarin (PUE) is a compound isolated from the roots of Pueraria lobata. We studied the pharmacokinetics and tissue distribution kinetics of PUE in Sprague-Dawley rats following intraperitoneal administration of three concentrations. Indirect competitive ELISA based on an anti-PUE monoclonal antibody was used to determine the concentration of PUE in the blood, heart, liver, spleen, lung, kidney, hippocampus, cerebral cortex, and striatum. The plasma and tissue distribution kinetic characteristics following a single injection of PUE (20, 40, and 80 mg/kg) were calculated using a non-compartment model. In the high-dose (80 mg/kg) and medium-dose (40 mg/kg) groups, the kinetic profile of PUE in blood and kidney samples showed two absorption peaks, while that of the other tissues showed only one peak. In the low-dose (20 mg/kg) group, there was only one peak, irrespective of the sample type. Pharmacokinetic parameters such as the area under the curve, C_max, and T_max varied according to the administered dose. AUC and C_max values increased dose-dependently. PUE was widely distributed in areas of the brain such as the hippocampus, cerebral cortex, and striatum, providing a foundation for guiding the use of PUE in the treatment of cerebral ischaemic stroke and neurodegenerative diseases.