Taurine Deficiency in Tissues Aggravates Radiation-Induced Gastrointestinal Syndrome.

Ionizing radiation administered for cancer treatment or from nuclear plant accidents are two common causes of radiation exposure. Ionizing radiation exposure generates reactive oxygen species and free radicals, which cause oxidative stress. We previously reported that taurine contributes to the recovery from radiation-induced injuries, suggesting its potential as a radioprotector and radiation mitigator. However, the effect of taurine on radiation-induced gastrointestinal syndrome remains poorly understood. The aim of this study was to examine the effect of taurine tissue depletion on radiation-induced gastrointestinal syndrome. Mouse models of radiation-induced gastrointestinal syndrome were established in TauT+/+ and TauT-/- mice by whole-body X-irradiation. We examined the 30-day survival rate, as well as the crypt-villus structure and proliferation of proliferating cell nuclear antigen (PCNA) + cells in the small intestine. The survival rate of TauT-/- mice was significantly lower than that of TauT+/+ mice. The villi in the small intestine of TauT-/- mice were significantly shorter than those in TauT+/+ mice. Additionally, there were significantly fewer PCNA+ cells in TauT-/- mice than in TauT+/+ mice. These data demonstrate that taurine is a key regulator of crypt stem cells and plays an important regulatory role in intestinal cell survival, proliferation, and fate. Therefore, taurine may reduce radiation-induced gastrointestinal syndrome.

Protective Effects of Taurine on the Radiation Exposure Induced Cellular Damages in the Mouse Intestine.

There has been a growing interest in radiation effects as a result of the Fukushima nuclear power plant accident in 2011. Exposure to ionizing radiation causes oxidizing events to different organs such as the bone marrow, intestine, and kidney, which can result in radiation-induced injuries. Taurine (2-aminoethanesulfonic acid) is a sulfur-containing amino acid possessing several important physiological functions, including membrane stabilization, anti-oxidative activity, anti-inflammatory effects and modulation of intracellular calcium levels. Taurine appears to be an attractive candidate for use as a radioprotector and as a radiation mitigator, but its protection mechanism against radiation-induced cell damage is still unclear until now. In this review we describe some of the mechanisms explaining the radioprotective/mitigating effects of taurine on radiation-induced cellular damage and our recent findings on this subject.

The Potential Effects of Taurine in Mitigation of Radiation Nephropathy.

Taurine (2-aminoethanesulfonic acid) is a sulfur-containing organic acid possessing several important effects, including antioxidant and anti-inflammatory ones. Exposure to ionizing radiation generates free radicals and reactive oxygen species (ROS) in irradiated cells, and free radical generation leads to oxidative stress. It is known that radiation nephropathy includes an inflammation-based process in which ROS and cytokines are responsible. Different doses of explored radiation can cause apoptosis, inflammation and a profound oxidative stress in kidneys. Oxidative stress is involved in renal injury after exposure to both ionizing radiation and inflammation. In this review, we describe the protective effect of taurine against several kidney diseases and the potential effects of taurine in the mitigation of radiation nephropathy. We also report that X-irradiation decreased the expression of taurine and TauT in the kidney. Taurine administration suppressed the decrease in the expression of taurine and TauT in the kidney after radiation exposure. Taurine might contribute to the mitigation of kidney injury induced by radiation.