Despite there is growing interest in the therapeutic applications of Δ9 - tetrahydrocannabinol (THC), it has been reported to induce oxidative damage in vivo and in vitro. This study was designed to study oxidative stress contributed by THC in blood parameters and brain of rat and to evaluate the protective impact of ascorbic acid (vit C) as antioxidant nutrient against oxidative stress. A number of sixty healthy male Albino rats were used in the current experiment. They were assigned to 3 equal groups of 20 rat each. The first group served as control group. The second group received commercial diet and injected intraperitonealy (i.p) with THC at a dose of 60 mg/kg body weight. The third group allowed to commercial diet supplemented with a dose of 5 µgm vit C /day/rat and each rat was injected ip with THC at a dose of 60 mg/kg body weight. Blood analysis and histological studies of cerebrum and cerebellum were used as a measure of oxidative stress.
Results revealed that the i.p injection of THC elevated blood cholesterol, LDL, triglyceride, and homocyctien (Hcy) with decrease in HDL, pyridoxal phosphate (PLP) and vitamin C as compared to control rats. However the increase in LDL was significant. Many degenerated pyramidal cells surrounded by wide, clear intraneuronal cytoplasmic vacuoles, congestion of the blood vessels and strophied cells were showed. Also the degeneration extend to meninges which characterized by the presence of widening in the subrarachnoid spaces were observed. The cerebellum showing presence of diffuse eosinophilia of neurons with degeneration in the form of pyknosis of Purkinje cells. Rats injected with THC and received vit C in their diets showed a decrease in blood cholesterol, LDL, triglycreides and Hey levels as compared to THC group. There were increase in blood HDL, PLP and vitamin C values associated with many pyramidal and nerve cells with neuroglia in the cerebral cortex.
In conclusion, the oxidative change in lipids is an important event in the pathogenesis of neurodegeneration induced by THC and dietary vit C supplementation success to protect blood and brain tissues. from that oxidative stress.