Effects of tenuigenin on the expression of brain-derived neurotrophic factor and its receptor tyrosine protein kinase B in the hippocampus of Alzheimer's disease model rats

Abstract

Objective To investigate the effects of tenuigenin (TEN) on expression of brain-derived neurotrophic factor (BDNF), and its receptor tyrosine protein kinase B (TrkB) in the hippocampal CA1 region of Alzheimer's disease (AD) model rats.  Methods Sixty male Wistar rats were divided randomly into 4 groups: the control group, the model group, 12.50 mg/ml TEN group and 37.50 mg/ml TEN group. AD model rats were made by injecting ibotenic acid into Meynert basal nuclei of aging rats induced by D-galactose. The expressions of BDNF and its receptor TrkB in the hippocampal CA1 region were measured by immunohistochemistry method.  Results The positive expressions of BDNF and TrkB were pale brown and mainly in neuronal cell membrane of the hippocampal CA1 region measured by immunohistochemistry method. The average absorbance values of BDNF and its receptor TrkB in the control group were 0.47 ± 0.02 and 0.46 ± 0.05, while in the model group were 0.30 ± 0.02 and 0.21 ± 0.07 which were significantly lower than that of the control group (P = 0.000, for all). The average absorbance values of BDNF and its receptor TrkB in 12.50 mg/ml TEN group were 0.35 ± 0.05 and 0.32 ± 0.07, which were significantly higher than that of the model group (P = 0.000, for all) and 37.50 mg/ml TEN group were 0.43 ± 0.05 and 0.37 ± 0.03, which were significantly higher than that of the model group (P = 0.000, for all). The average absorbance values of BDNF and its receptor TrkB in 37.50 mg/ml TEN group increased significantly than that in 12.50 mg/ml TEN group (P = 0.000).  Conclusions TEN can dose-dependently increase BDNF and its receptor TrkB expression in the hippocampal CA1 region of Alzheimer's disease model rats, which may partly explain the beneficial effects of TEN on cognitive function.

doi: 10.3969/j.issn.1672-6731.2014.05.011