The effect of oral caprylic acid administration on acyl ghrelin and growth hormone levels and anxiety in growing rats

Caprylic acid is a medium chain fatty acid containing 8 carbons. Caprylic acid is necessary for the conversion of ghrelin which is known as the hunger hormone, to its active form acyl ghrelin. In addition to its functions related to the control of food intake, acyl ghrelin increases the secretion of growth hormone. It is possible that dietary caprylic acid increases the active form of ghrelin and supports growth through this mechanism. The aim of this thesis study is to investigate the effect of long-term oral caprylic acid administiration to serum acyl ghrelin, growth hormone, IGF-1 and insulin levels, growth parameters and anxiety levels in rats. For this purpose, 3 week-old 30 Wistar albino male rats were divided into 3 groups as control, low level caprylic acid and moderate caprylic acid groups. Caprylic acid was administered by oral gavage for 30 days. During the application, the growth parameters and food consumption of the rats were followed, subsequently acyl ghrelin, growth hormone, IGF-1 and insulin levels were measured. In addition, the anxiety levels of the animals were evaluated with the elevated plus maze and light/dark box tests. As a result of our study, it was found that the doses of caprylic acid we applied to growing rats caused a decrease in growth hormone, on the other hand acyl ghrelin, IGF-1 and insulin levels were not changed. In addition, no difference was found between the groups in terms of growth, appetite or anxiety levels. Our thesis is important in that it is the first study to examine the growth, food consumption, and acyl ghrelin and growth hormone levels of caprylic acid together in growing rats. More studies are needed to elucidate the interaction between caprylic acid and ghrelin hormone and its effect on growth-related hormone levels, growth parameters, appetite and anxiety.