Effect Of Catechin And Levothyoxine On Oxidative Stress Level And Cognitive Function In Hypothyroidism Rat

Objective To observe the effects of Levothyoxine,catechin and the two-drug combination therapy on the cognitive function and the levels of 8-OHd G?PON-1 in the serum and apoptosis protein caspase-3 in hippocampus tissue of hypothyroidism rat.Methods Fifty male SD rats were selected,ten of them were selected randomly as the normal group.The rest were induced to hypothyroidism models,by adding propylthiouracil(PTU)in their daily drinking water,then divided them into four groups randomly: the hypothyr oidism group(PTU group),the catechin group,the levothyoxine group(L-T4 group),two-drug combination group.Behavior were detected by Morris Water Maze.The levels of 8-OHdG?PON-1 in the serum were measured using enzyme-linked immunosorbent assay(ELISA)method.The level of apoptosis protein caspase-3 in hippocampus tissue was measured by western-blot method.Results Part one: Compared with the normal group,the escape latency in the PTU group was longer(P<0.05);Compared with the PTU group,the escape latency in the L-T4 group and the two-drug combination group was shorter(P<0.05).Part two:(1)Compared with the normal group,the level of 8-OHd G in the serum and the level of caspase-3 in hippocampus tissue in the PTU group was both obviously higher(P<0.05);Compared with the PTU group,the level of 8-OHd G in the serum and the level of caspase-3 in hippocampus tissue in the L-T4 group and the two-drug combination group was both obviously lower(P<0.05).(2)Compared with the normal group,the level of PON-1 in the serum in the PTU group were obviously lower(P<0.05);Compared with the PTU group,the level of PON-1 in the serum in the L-T4 group and the two-drug combination group were obviously higher(P<0.05).Conclusion Hypothyroidism can decrease the ability of oxidative stress and increase the apoptosis.Levothyoxine and catechin can improve the ability of oxidative stress and decrease apoptosis.Furthermore,the two-drug combination therapy have an additive effect on improving the ability of oxidative stress and decreasing apoptosis.