Taurine

Taurine, or 2-aminoethanesulfonic acid, is an organic acid. It is also a major constituent of bile and can be found in lower amounts in the tissues of many animals including humans. Taurine is a derivative of the sulfur-containing (sulfhydryl) amino acid, cysteine. Taurine is the only known naturally occurring sulfonic acid.
Taurine is named after the Latin taurus, which means bull or ox, as it was first isolated from ox bile in 1827 by Austrian scientists Friedrich Tiedemann and Leopold Gmelin. It is often called an amino acid, even in scientific literature, but as it lacks a carboxyl group it is not strictly an amino acid. It does contain a sulfonate group and may be called an amino sulfonic acid. Small polypeptides have been identified which contain taurine, but taurine is normally found in free form in the body.
Taurine is combined with chenodeoxycholic acid and cholic acid to form the bile salts sodium taurochenodeoxycholate and sodium taurocholate, which together serve as surfactants (break up fats to make digestion easier). Taurine has also been implicated in a wide array of other physiological phenomena including inhibitory neurotransmission, membrane stabilisation, fatty tissue regulation, calcium homeostasis and recovery from osmotic shock.
Prematurely born infants who lack the enzymes needed to convert cystathionine to cysteine may become deficient in taurine. Thus, taurine is a dietary essential nutrient in these individuals and is often added to many infant formulas as a measure of prudence. There is also evidence that taurine is beneficial for adult human blood pressure and possibly, the alleviation of other cardiovascular ailments.
Obese mice demonstrate reduced blood levels of taurine, which may promote further weight gain, and taurine supplementation prevented obesity in mice fed a high-fat, low-taurine diet. Recent studies have also shown that taurine can influence (and possibly reverse) defects in nerve blood flow, motor nerve conduction velocity, and nerve sensory thresholds in experimental diabetic neuropathic rats. Taurine levels were found to be significantly lower in vegans than in a control group on a standard American diet.
According to some animal studies, taurine may act as a modulator or anti-anxiety agent in the central nervous system.
In recent years, taurine has become a common ingredient in energy drinks. Taurine is often used in combination with bodybuilding supplements such as creatine and anabolic steroids, partly due to recent findings in mice that taurine alleviates muscle fatigue in strenuous workouts and raises exercise capacity. Taurine has also been shown in diabetic rats to decrease weight and decrease blood sugar.
Taurine is essential for cat health, as cats cannot synthesize the compound. The absence of taurine causes a cat's retina to slowly degenerate, causing eye problems and (eventually) irreversible blindness as well as hair loss and tooth decay. This condition is called central retinal degeneration (CRD). In addition, taurine deficiency can cause feline dilated cardiomyopathy, and supplementation can reverse left ventricular systolic dysfunction.