The effect of alpha lipoic acid and caffeine loaded into chitosan nanoparticles on the hypothalamic amino acid neurotransmitters in a rat model of obesity

The present study was carried out to investigate the physiological role of the hypothalamic amino acid neurotransmitters (AAs) in feeding behavior and obesity. Caffeine loaded into chitosan nanoparticles (Caf-CNPs) and/or α-lipoic acid (α-LA) were used to investigate their therapeutic effects on the changes in hypothalamic glutamine, glutamate, aspartate, GABA, glycine and taurine and serum levels of leptin and ghrelin in addition to the body mass index (BMI) of obese rats. Rats were divided into lean control group, rat model of obesity induced by high fat diet (HFD) group (obese control), and rat model of obesity group treated with Caf-CNPs and /or α-LA. Obese rats showed a higher value of BMI, elevated levels of leptin, reduced levels of ghrelin, and increased levels of hypothalamic glutamate, aspartate, GABA and taurine. Treatment with Caf-CNPs improved BMI and didn't affect the changes in hypothalamic AAs, leptin and ghrelin induced in obese rats. Treatment with α-LA improved BMI, leptin and ghrelin levels and restored the changes in AAs. Co-administration of Caf-CNPs and α-LA restored BMI, leptin, ghrelin, aspartate and taurine to control-like values, however, there were elevated levels of glutamine, glutamate, GABA and glycine. The present study showed the substantial role of hypothalamic AAs in controlling feeding behavior and development of obesity. It may be concluded that Caf-CNPs and/or α-LA could potentially act as anti-obesity agents.