Obestatin and Its Fragments: A New Approach to the Regulation of Body Weight under Normal and Pathological Conditions

Abstract

Gastrointestinal diseases and eating disorders are among the most common pathologies in the world. One of the most widespread and dangerous consequence of many eating disorders is an uncontrolled weight gain that often leads to obesity. This review focuses on the 15-year-long studies of obestatin, one of the potential regulators of eating behavior. This peptide contains 23 amino-acids and appears due to the processing of the preproghrelin gene responsible for the coding of another orexigenic protein ghrelin. Obestatin and ghrelin have multiple physiological functions, including appetite regulation. Obestatin was originally obtained from the gastric mucosa in rats, but subsequent studies showed that it could be expressed in various tissues and had different effects in various organs and tissues. This review emphasizes possible anorexigenic effects of this peptide and their mechanisms. Despite the 15 years of research on obestatin, its influence on different organs and the mechanism of anorexigenic effects in particular bring about a lot of discussion. This is primarily due to the ambiguity of the peptide receptors’ determination and is also related to the possible degradation of the molecule into small fragments, which, in turn, can have their own effects. The local effects of obestatin and its derivatives in peripheral tissues and the possible effect at the central level indicate the potential of these peptides for further studies. For example, these compounds can be considered as the potential therapeutic compounds for eating disorders’ treatment. The aim of this work was to describe the relevance of the problem associated with obesity treatment and to summarize the results of numerous studies on obestatin and its fragments and their effects on appetite regulation in order to explain its possible mechanisms.