Taurine, 2-aminoethanesulfonic acid, is the second most abundant endogenous amino acid in the CNS after glutamate. This chemical plays many roles in the body, including thermoregulation, stabilization of protein folding, anti-inflammation, antioxidant activity, osmoregulation, calcium homeostasis, and CNS development. Previous reports in the literature have revealed taurine deficiency in the brains of Alzheimer's patients. Arai et al. reported that postmortem brain tissue from Alzheimer's patients had lower concentrations of taurine in the temporal cortex compared to brain tissue from control patients. Numerous pieces of evidence suggest taurine as a therapeutic agent for Alzheimer's. Recently, taurine has been reported to help improve cognitive function and protect against neuropathology in an animal model of Alzheimer's. Jakaria et al. reported that taurine showed therapeutic potential against neurological disorders, including Alzheimer's. Santa-Maria et al. reported that taurine binds to Aβ plaques with weak antifibrillogenic effects. Additionally, intravenously administered Taurine prevents Aβ neurotoxicity and cognitive impairment. To date, no reports of potential side effects of Taurine have been documented, and due to its non-toxic properties, Taurine has been used in the body and in foods. Biologically, Taurine plays several important roles in calcium signaling modulation, osmoregulation, and membrane stabilization. It has been reported that the sulfonic acid group in Taurine binds to Aβ and prevents glycosaminoglycans (GAGs) from binding to Aβ. In Alzheimer's patients, amyloid peptide binds to GAGs, causing plaque buildup in the brain and destroying neurons. Another clinical study reported that 3-amino-1-propane sulfonic acid (3-APS) was designed as an anti-amyloid treatment and significantly reduced Aβ in the brain. Taurine has structural similarity to 3-APS; Therefore, we hypothesized that Taurine would ultimately bind directly to Aβ to inhibit the interaction of GAGs with amyloid peptide. This sequence of events is thought to ultimately lead to the downregulation of mGluR5. Several studies in rodents have also demonstrated the effects of Taurine on Alzheimer's disease. Kim et al. reported that Taurine significantly improved hippocampus-related cognitive deficits in an Alzheimer's mouse model. Another recent study reported that Taurine directly binds to AβO and consequently improves behavioral deficits of Alzheimer's, such as learning and memory loss. Roberto et al. reported that Taurine strongly protected neurons against the in vitro neurotoxicity of Aβ. Thy also showed in an in vitro study that Taurine prevented neurotoxicity caused by Aβ and glutamate receptor agonists. However, all of the studies cited above were based on ex vivo or behavioral observations rather than changes at the molecular level. Alzheimer's progression typically begins with a change at the molecular level, followed by clinical symptoms due to functional and structural changes in the brain. The novelty of this study lies in the evaluation of Taurine's therapeutic effects on Alzheimer's disease using functional PET.

PUBLICATIONS ON THE SUBJECT:

** Sci Rep. 2020 Sep 23;10(1):15551.doi: 10.1038/s41598-020-72755-4.

Evaluation of the neuroprotective effect of taurine in Alzheimer's disease using functional molecular imaging

** J Immunol Res. 2021 Jul 5;2021:7497185.doi: 10.1155/2021/7497185. eCollection 2021.

Neuroprotective Effect of Taurine against Cell Death, Glial Changes, and Neuronal Loss in the Cerebellum of Rats Exposed to Chronic-Recurrent Neuroinflammation Induced by LPS

** Mol Med Rep. 2018 Nov;18(5):4516-4522.doi: 10.3892/mmr.2018.9465. Epub 2018 Sep 6.

Protective effects of taurine against inflammation, apoptosis, and oxidative stress in brain injury

** Redox Biol. 2019 Jun;24:101223.doi: 10.1016/j.redox.2019.101223. Epub 2019 May 21.

Taurine and its analogs in neurological disorders: Focus on therapeutic potential and molecular mechanisms

** Sci Rep. 2014 Dec 12;4:7467. doi: 10.1038/srep07467.

Taurine in drinking water recovers learning and memory in the adult APP/PS1 mouse model of Alzheimer's disease

** Stem Cell Res. 2015 May;14(3):369-79.doi: 10.1016/j.scr.2015.04.001. Epub 2015 Apr 10.

Taurine increases hippocampal neurogenesis in aging mice

** Nutr J. 2021 Jun 8;20(1):53. doi: 10.1186/s12937-021-00712-6.

The effects of Taurine supplementation on inflammatory markers and clinical outcomes in patients with traumatic brain injury: a double-blind randomized controlled trial