Effects of the Chinese Yi-Qi-Bu-Shen Recipe extract on brainstem auditory evoked potential in rats with diabetes

This study was designed to investigate the effects of the Chinese Yi-Qi-Bu-Shen Recipe (YB) on brain stem auditory evoked potential (BAEP) in diabetic rats and on the protection of the diabetic rat brain's functional lesion. Thirty-three male rats were randomly divided into three groups: the normal control group (NC), the diabetic group (DM), and the diabetic rats treated with YB group (DM + YB). Blood glucose and body weight were measured every three weeks. After six weeks, the serum insulin, blood biochemical indices, superoxide dismutase, malondialdehyde, monoamine neurotransmitters, and BAEP were measured. Compared with the NC group, the waves III, V PLs, and the I-III, I-V IPLs of BAEP in the DM group were significantly delayed (all P < 0.05). However, YB-treated diabetic rats maintained a normal brainstem function over the experimental period. Compared with the NC group, the waves I, III, V PL, and waves I-III, III-V and I-V IPLs of BAEP in the DM + YB group were very close (all P > 0.05). On the other hand, compared with the DM group, the III, V PLs and the I-III,I-V IPLs of BAEP in the DM + YB group were significantly improved. It was discovered that the central conduction time of rats with diabetes had a close correlation with serum insulin, blood glucose, malondialdehyde, and insulin resistance index. Our results suggest that YB extract has a beneficial effect in preserving the brain's electrophysiological function in diabetic rats, likely through its antihyperglycemic activity, ability to reduce insulin resistance, and antioxidant activity. (C) 2011 Elsevier Ireland Ltd. All rights reserved.