Studies On Anti-apoptotic And Anti-dementia Effects Of Melatonin And Its Mechanism Of Action

Part I Effects of Melatonin and 17—β Estrogen on alleviating Central nervous system dysfunction in ovariectomized rats and its mechanismAlzheimer's disease is the leading dementia; the burden is especially for women whose prevalence is double that of men. Accumulating evidence from case-control and cohort indicated that a woman's estrogen use after menopause was associated with a reduced risk of developing of AD, and among woman with AD estrogen therapy was linked to have better performance on a variety of cognitive measures. Moreover, results of several small interventional studies suggested that estrogen treatment might improve AD symptoms.Melatonin as a neuro-endocrine hormone, which mainly secreted by pineal gland, involved in much physiological and pathological process in the body. There existed hypothalamo-pituitary-adrenal axis dysfunction in the postomenopause woman (PMW), it was reported that aged PMW the cortisol levels were enhanced at selected circadian times and were stimulated by melatonin. Moreover , Melatonin was reported to be a most potent effective endogenous free radical scavenger and antioxidant.One of the typical pathological marks of the AD is the progressive neuron loss , The progressive neuron apoptosis were observed in the brain of the AD patient ,More and more evidence suggested that neuron loss which cause the memory and cognition dysfunction in the AD may mainly due to neuron apoptosis .Many factors, especially Bcl/Bax superfamily involved in the apoptotic procedure, as the modulator involved in the regulation of the apoptosis .Many scientists put the emphasis on studying the relationship between the apoptosis and the mitochondria dysfunction . As the accelerate of the energy in the neuron , mitochondria dysfunction will generate free radical , increase the release of the cytochrome C from the mitochondria to cytoplasm which will in turn active the Caspase —the executor of the apoptosis , trigger the apoptotic cascade.The detail mechanism of action of the estrogen remained controversial , Emerging evidence suggested that estrogen may play its effects of the anti-dementia by acting as...