Age-Related Changes in the Melatonin and Thymulin Biorhythms as Risk Factors for Human Neurodegenerative Diseases

The frequency of age-related neurodegenerative pathology, such as Parkinson's and Alzheimer's diseases, brain ischemia and multiple sclerosis increases worldwide and has great socio-economic implications.The use of approaches based on investigation the pathogenic factors of their development may be perspective in the prevention and treatment of such diseases.Circadian and circannual rhythms play a key role in the adaptative changes of human neuroendocrine and immune systems to the light and temperature.The rhythmicity of these systems is disturbed in human aging that may be connected with desynchronosis of pineal gland melatonin production.This process becomes more intensive during development of the neurodegenerative diseases.Thymic endocrine function (thymulin production) is the important part of chronobiological organization of immune system.The circadian and circannual rhythms of thymulin depend on the synchronizing influence of melatonin.Melatonin production disorders lead to the intra-immune desynchronosis via disturbances of the circadian and circannual rhythms of thymulin and its interactions with the endocrine glands (hypophysis, adrenal glands, gonads etc) both in aging and age pathology.Melatonin treatment improves sleep-wake rhythm and produces antiapoptotic, antioxidant and anti-inflammatory effects in the brain at neurodegenerative diseases and slows down development of this pathology.Moreover, melatonin treatment leads to the suppression of age-related changes in the rhythmicity of immune and neuroendocrine systems functions.Such melatonin effect is realized via synchronous influence on the circadian and circannual rhythms of thymulin production.Therefore melatonin seems to be perspective for restoring disturbed rhythmicity of immune and neuroendocrine systems in: A. accelerated human aging with pineal gland dysfunction and B. Patients of different age and sex suffering from neurodegenerative diseases making individual hormone dose correction.