Pineal peptides restore the age-related disturbances in hormonal functions of the pineal gland and the pancreas

The purpose of this research was to study age-related changes in functioning of pineal and pancreatic glands of non-human primates, rhesus monkeys, and to elucidate the possibility of their corrections with the help of epitalon, a synthetic analogue of the pharmacopoeia drug epithalamin. In old (20-27 years) animals, the basal plasma levels of glucose and insulin were found to be higher, while the night melatonin level was lower in comparison with (6-8 years) young animals. After the glucose administration to old monkeys, a larger area under the curve of the plasma glucose response, a reduced glucose 'disappearance' rate, and a reduced insulin peak (5 min after the glucose administration) were observed in comparison with young animals in similar experiments. The epitalon administration to old monkeys caused the decrease in the basal levels of glucose and insulin and the increase in the basal night melatonin level. Additionally, in the case of old monkeys, epitalon decreased the area under the plasma glucose response curve, markedly increased the glucose 'disappearance' rate and normalized the plasma insulin dynamics in response to glucose administration. Yet, it has not affected the hormonal and metabolic changes in young animals. Thus, epitalon is a promising factor for restoring the age-related endocrine dysfunctions of primates. (C) 2004 Elsevier Inc. All rights reserved.