[Effects of naokang erhao decoction on cognitive ability and hippocampal apoptosis-related proteins in diabetic rats].
OBJECTIVE
To investigate the effects of Naokang Erhao decoction on the cognitive ability and the expression of Caspase-3, Bax and Bcl-2 proteins in hippocampus of type 2 diabetic rats.


METHODS
The diabetes mellitus (DM) rat model was produced by intraperitoneal injection of streptozotocin and fed with high fat and sucrose diet. The Naokang Erhao-treated rats were intragastrically given different doses of Naokang Erhao, whereas the control and DM model groups were given double distilled water for 4 consecutive weeks. Learning and memory abilities of rats were tested with the Morris water maze. The expression of Caspase-3, Bax and Bcl-2 proteins in hippocampal CA1 region was measured by immunohistochemistry.


RESULTS
Both escape latency and swimming distance of type 2 DM rats were significantly prolonged in comparison of those in normal control (P < 0.01), and swimming time in the platform of previous quadrant was significantly shorter in model group (P < 0.01). Furthermore, the expression of Bcl-2 protein was decreased, while Caspase-3 and Bax in the hippocampus were increased compared with the control group (P < 0.01). Four weeks of treatment with Naokang Erhao decoction remarkably improved the learning and memory abilities of DM rats, increased the expression of Bcl-2 and decreased the expression of Caspase-3 and Bax in hippocampal CA1 region of model rats (P < 0.01 or P < 0.05).


CONCLUSIONS
Naokang Erhao decoction may inhibit apoptosis by increasing the expression of Bcl-2 and reducing the expression of Caspase-3 and Bax in the hippocampus, and this may be one of the mechanisms by which Naokang Erhao decoction improves cognitive ability in DM rats.
Xuanwu Hospital, Capital Medical University, Beijing 100053, China. cyj0504@sina.com.cn
Yujing
Y
Chen
Lin
L
Li
Zongxin
Z
Li
Xiaobo
X
Huang
Li
L
Zhang
Wenqiang
W
Chen
D045784:Abietanes / Q000494:pharmacology; D000098:Acetophenones / Q000494:pharmacology; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D001565:Benzoates / Q000494:pharmacology; D001952:Bridged-Ring Compounds / Q000494:pharmacology; D056547:CA1 Region, Hippocampal / Q000187:drug effects* / Q000378:metabolism; D053148:Caspase 3 / Q000187:drug effects / Q000378:metabolism; D003072:Cognition Disorders / Q000188:drug therapy* / Q000378:metabolism; D003929:Diabetic Neuropathies / Q000188:drug therapy* / Q000378:metabolism; D004338:Drug Combinations; D004365:Drugs, Chinese Herbal / Q000494:pharmacology; D005960:Glucosides / Q000494:pharmacology; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000187:drug effects / Q000378:metabolism*; D011719:Pyrazines / Q000494:pharmacology; D051381:Rats; D051028:bcl-2-Associated X Protein / Q000187:drug effects / Q000378:metabolism*
D045784:Abietanes; D000098:Acetophenones; D001565:Benzoates; D001952:Bridged-Ring Compounds; D004338:Drug Combinations; D004365:Drugs, Chinese Herbal; D005960:Glucosides; D019253:Proto-Oncogene Proteins c-bcl-2; D011719:Pyrazines; D051028:bcl-2-Associated X Protein; C572199:naokangning; D053148:Caspase 3