Potent antioxidant alpha lipoic acid reduces STZ-induced oxidative stress and apoptosis levels in the erythrocytes and brain cells of diabetic rats

Abstract

Diabetes, which causes oxidative stress-induced neuronal damage, is still one of the most important chronic health problems in the world. It can cause serious cellular loss and damage throughout the course of the disease. It is hypothesized that increased oxidative stress in this process increases free reactive oxygen species (ROS) and apoptotic markers and causes diabetic damage. Alpha-Lipoic acid (α-LA), which has a direct antioxidant effect in ROS reduction reactions, is also among the main components of the antioxidant system that works for free radical control and apoptosis. To understand the role of α-LA in reducing diabetes-induced oxidative damage, we examined the production of ROS in the brain cortex and erythrocytes of rats and their effects on markers of apoptosis. Forty adult Wistar albino rats were divided into four groups as control, α-LA, diabetic (DIA), and DIA+α-LA. For the induction of diabetes, the intraperitoneal injection of a dose of streptozotocin (STZ) (45 mg/kg) was used. α-LA (50 mg/kg) was applied to the groups of α-LA and DIA+α-LA for 14 days. At the end of the experiment, the brain cortex tissue and erythrocyte samples were taken from the rats. The levels of apoptosis, caspase 3, caspase 9, mitochondrial membrane potential, intracellular ROS, and lipid peroxidation were increased in the STZ group, although their levels were decreased in the DIA+α-LA group by the injection of α-LA. The STZ treatmentinduced decreases of cell viability, reduced glutathione, and glutathione peroxidase were increased in the brain and erythrocytes by the treatment of α-LA. In conclusion, diabetes acted a role in neuronal damage caused by increased ROS and apoptosis. We observed that α-LA induced a modulatory role on the apoptotic, oxidant, and antioxidant parameters in the brain and erythrocyte. The neuroprotective role of α-LA treatment may be explained by its modulating activity against increased oxidative stress and apoptosis.