Taurine Modulates TRH and TRH-like Peptide Expression throughout the Brain and Peripheral Tissues of Male Rats

Taurine, a semi-essential amino acid, declines by 80% in mice and monkeys with aging. Taurine has therapeutic effects ranging from treatment of depression, Alzheimer’s and Parkinson’s disease, obesity, diabetes, neuroendocrine function, osteoarthritis, neurodegeneration and aging. TRH and TRH-like peptides, with the structure pGlu-X-Pro-NH ₂ , where “X” can be any amino acid reside, have reproductive, caloric-restriction-like, anti-aging, pancreatic-β cell-enhancing, cardiovascular, and neuroprotective effects. Sixteen young adult male Sprague-Dawley rats were divided into 4 groups. Control group remained on ad libitum chow and water for 10 days. Acute group received ad libitum chow and water for 9 days and then 2.5% taurine in rat chow for 24 h. Chronic animals received taurine in chow for 10 days. Withdrawal rats received taurine chow for 8 days and then normal chow for 2 days. TRH and TRH-like peptide levels were measured in 12 brain regions and 7 peripheral tissues. Significant changes in the levels of TRH and TRH-like peptides occurred throughout the brain and peripheral tissues in response to taurine treatment. The sensitivity of TRH and TRH-like peptide expression to taurine treatment, particularly in the cerebellum, frontal cortex, amygdala and hippocampus, liver, epididymis and pancreas is consistent with TRH and TRH-like peptides participating in the therapeutic effects of taurine on neurological, reproductive, and metabolic disorders.