Assessment of Renal Sodium-Glucose Cotransporter 2 (SGLUT2) Expression and Glucose Levels in Blood and Urine after Chronic Consumption of Oxidized Palm Oil Diets

This study investigates the influence of consumption of oxidised palm oil on kidney tissue concentration of Sodium-Glucose Cotransporter 2 (SGLUT2) and glucose levels in blood and urine. A total of twenty (20) apparently healthy adult male wistar rats weighting between 140-160g were used in this study. The experimental animals were randomly divided into four (4) groups of five (5) animals each. Group 1 served as the control group and were fed with normal rat chow and water ad libitum, group 2, 3 and 4 were fed with 15% fresh palm oil (FPO) diet, 15% photo-oxidised palm oil (PPO) diet and 15% thermo-oxidised palm oil (TPO) diet respectively. The experiment lasted for 90 days. After the period of experiment, the animals were sacrificed under urethane anesthesia and blood samples were collected via cardiac puncture for determination of blood glucose level, while the kidneys were harvested for kidney tissue SLUT2 concentration. SGLUT2 was determined using immunohistochemistry method. The results revealed that there was a significant increase in blood and urine glucose levels of TPO-diet fed group when compared with the control group. Also, there was a significant decrease in the mean percentage expression of SGLUT2 in both thermally oxidized palm oil (TPO)-diet fed and photo-oxidized palm oil (PPO)-diet fed groups when compared with the control and fresh palm oil (FPO)-diet fed groups. These results suggest that oxidative modifications in palm oil may have an adverse impact on renal SGLUT2 expression. In conclusion, this study demonstrates that consumption of thermo-oxidized and photo-oxidized palm oil significantly decreases renal SGLUT2 expression, likely as a response to oxidative stress.