Serum Amino Acid Levels in Rats under Long-term Administration of Progesterone and Melanin Treatment

Background. Obesity is one of the most common complex health problems in the world. Main reasons of the development of obesity are marketing the unhealthy food, passive lifestyle, hormonal disorders. Obesity can lead to the development of diabetes mellitus, ischemic heart disease and certain cancers. Numerous neuropeptides and transmitters as well as multiple peripheral hormones take part not only in the regulation of feeding but also in the physical activity. Peptides - serotonin, insulin, glucagon, hormones of hypothalamus and hypophysis, thyroid hormones are the examples of weight regulated hormones. The use of drugs based on steroid hormones, particularly progesterone, can also be one of many factors contributing to obesity. It is known that progesterone which enters the female body artificially leads to fat accumulation. Phenolic biopolymers are the most thoroughly studied natural genesis of macromolecular structures. Melanin occupies a special place among natural polymers. Melanin is chemically relatively inert, but at the same time it is the only polymer with biological properties of a stable free radical. These characteristics determine the structure of their photo- and radioprotective, antioxidant and other properties that is why melanin is widely used in medicine, pharmacology, cosmetology, agriculture and food industry. This article is focused on the molecular and clinical associations between melanin and serum amino acids under progesterone-induced obesity. Serum amino acids are a source for synthesis of hormones that have peptide and protein nature. Revealing these interactions and mechanisms of progesterone-induced obesity may improve our understanding of the complex treatment of obesity. In the current study we used white nonlinear female rats that were divided into three groups. Rats of group 1 – control; group 2 – progesterone-induced obese; group 3 – progesterone-induced obese group under melanin treatment (10 mg/kg body weight, treated daily during 28 days). Amino acid blood serum levels were determined by ion exchange chromatography analyzer (Spekman, Stein, Moore). The statistical analysis of data was carried out by the software package "Statistica 7.0". Values are statistically significant at p < 0.05. Results. The recent study has shown changes in amino acid levels in blood serum of rats under progesterone long-term administration and melanin treatment. Levels of the majority of amino acid content have decreased in rats under progesterone long-term administration and melanin treatment as compared with the control group. The obtained data have given some evidence that progesterone long-term administration has a significant influence on amino acids metabolism. Conclusion. Aromatic amino acids are the substrates for the of neurotransmit- Changes of content of aromatic amino acids can be a of disfunction of the synthesis of these neurotransmitters. The significant decrease of some amino acids, particularly BCAAs and aromatic amino acids, can show disorders of transport processes and metabolism of amino acids. This, directly or indirectFly, leads to weight disorders.