Diabetes mellitus is a metabolic disorder associated with an increased risk of depression. Diabetic rats exhibit depression-like behavior, and taurine, one of the most abundant free amino acids in the brain, reverses this depressive behavior.
Because taurine is a GABAA agonist modulator, we hypothesize that its antidepressant effect results from interaction on this system by altering α2 GABAA receptor subunit expression alongside changes in BDNF mRNA and memory in diabetic rats.
Streptozotocin-diabetic and nondiabetic Wistar rats were injected intraperitoneally with 100 mg/kg taurine or saline daily for 30 days. At the end of the experiment, the rats were exposed to the novel object recognition memory. Later, they were euthanized, the brains were weighed, and the hippocampus was dissected for α2 GABAA subunit and BDNF mRNA expression.
Real-time quantitative PCR (qPCR) showed that diabetic rats had lower α2 GABAA subunit and BDNF mRNA expression than nondiabetic rats, and taurine increased both parameters in these diseased rats. Taurine also reversed the lower brain weight and improved short-term memory in diabetic rats.
Thus, the antidepressant effect of taurine could be explained by interference with the GABA system, consistent with the neuroprotective effect shown here by preventing brain weight loss and improving short-term memory in diabetic rats.
Found at Alkohol adé (german)