The Kidney Beans (Phaseolus vulgaris) Pods Extract Affects the Central and Peripheral Serotonergic Systems in Rats With High-Calorie Diet-Induced Obesity

Abstract

Background: Overweight and obesity have become a global epidemic that presents a risk to health. Serotonin is involved in the regulation of many important functions of the body as in the periphery (as a hormone), as well as in the central nervous system as a neurotransmitter, which can be involved in central mechanisms that control food intake. The present work aimed to study the features of serotonin metabolism functioning under the effect of the kidney beans ( Phaseolus vulgaris ) pods extract in experimental obesity, which was induced by the consumption of high-calorie diet. Phaseolus vulgaris is the plant that possesses plenty of curative and therapeutic properties in particular for the treatment of diabetes mellitus, obesity, and cardiovascular diseases. It has been known that plant extracts, unlike synthetic drugs, can be used practically without toxic effects. Methods: Experiments were carried out on four groups of white nonlinear male rats (10 rats per group) during a 10-week period. Studies of the serotonergic system functioning were performed using ion-exchange chromatography, spectrofluorimetric and spectrophotometric methods. Results: The consumption of kidney beans ( Phaseolus vulgaris ) pods extract has a therapeutic effect on the obesity development in rats, as evidenced by changes in the functioning of the central and peripheral serotonergic systems. Tryptophan and serotonin levels have increased in duodenum mucosa compared to the obese rats, also had shown an increase of the serotonin synthesis enzymes activity (tryptophan hydroxylase and tryptophan decarboxylase) and a simultaneous decrease in the activity of monoamine oxidase. Central tryptophan and serotonin levels, as well as the activity of enzymes of the serotonin synthesis have increased compared to the obese rats while a simultaneous decrease in the activity of monoamine oxidase was observed. Conclusions: The obtained results indicated a therapeutic effect of the kidney beans ( Phaseolus vulgaris ) pods extract on the dysfunction of the serotonergic system under obesity development. J Endocrinol Metab. 2021;11(5):123-133 doi: https://doi.org/10.14740/jem650