Effects of soybean isoflavones on RAGE mediated signal transduction in the hippocampus of rats with Alzheimer's disease / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To investigate the effects of soybean isoflavones on receptor for advanced glycation end products (RAGEs) mediated signal transduction in the hippocampus of rats with Alzheimer's disease (AD).</p><p><b>METHODS</b>AD rat model was established by bilateral hippocampus injection of amyloid beta25-35 (Abeta25-35). Sixty rats were equally randomized into 5 groups, i.e., the model group, the high dose soybean isoflavones group (at the daily dose of 30 mg/kg), the low dose soybean isoflavones group (at the daily dose of 10 mg/kg), the estrogen group (at the daily dose of 0.4 mg/kg), and the sham-operation control group. Three days after modeling 2 mL soybean isoflavones or estrogen was respectively administrated to rats in the high dose soybean isoflavones group, the low dose soybean isoflavones group, and the estrogen group by gastrogavage. Equal volume of 0.5% CMC-Na was administered to rats in the model group and the sham-operation group. The treatment lasted for 21 days. The contents of RAGE and interleukin-6 (IL-6) in the hippocampus were measured by ELISA. The activity of cysteine-containing aspartate-specific protease-3 (Caspase-3) was measured by spectrophotometry. The expressions of phosphorylation extracellular signal-regulated kinase1/2 (P-ERK1/2) in the hippocampus were measured by immunohistochemical assay.</p><p><b>RESULTS</b>Compared with the model group, soybean isoflavones could significantly decrease the contents of RAGE and IL-6, the activity of Caspase-3, and the phosphorylation level of ERK1/2 in the hippocampus of AD model rats (P < 0.01).</p><p><b>CONCLUSION</b>Soybean isoflavones could down-regulate RAGE mediated inflammatory signal transduction in the hippocampus of AD rats, attenuate the inflammatory reactions, reduce the neurotoxicity of Abeta, and resist the apoptosis of hippocampal neurons.</p>

Experimental study on prevention and treatment of osteoporosis by phytoestrogen / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To observe the effect of phytoestrogen (PE) in preventing and treating osteoporosis in ovariectomized rats.</p><p><b>METHODS</b>Forty-five Wistar female rats, 3 months old, were randomly divided into the sham-operated group, the model group, low dose and high dose PE groups, and the positive control group, 9 in each group. All rats, except that those in the sham operated group were simutaneously operated, were ovariectomized. The medication started from the 31st days after operation by daily given saline per os to the sham-operated group and the model group, PE per os to the PE groups, and estradiol by intramuscular injection to the positive control group. The animals were sacrificed 90 days later, their sera were collected for determination of biochemical parameters, their right femoral bone was taken to detect the bone mineral density (BMD), left femoral bone to examine pathology of bone trabecula, and whole uterus was weighed to calculate the uterine index.</p><p><b>RESULTS</b>PE could increase the BMD level, serum estradiol and inorganic phosphorus content, and uterine index, lower serum BGP, tartrate-resistant acid phosphatase (TRAP), alkaline phosphatuse (AKP) and interleukin-6 levels. Pathological examination showed that in the model group, the cortex of bone thinned, bone trabecula thinned also, with poor integrity, distorted, broken and decreased in size, while in the PE groups, the above-mentioned changes were significantly alleviated.</p><p><b>CONCLUSION</b>PE is effective in preventing and treating osteoporosis in ovariectomized rats.</p>