Sulfur-containing amino acid

In the brain and spinal cord, white blood cells, heart and muscle cells, retina, and almost all other tissues, taurine is one of the most prevalent amino acids [1]. In addition to controlling intracellular calcium concentration and avoiding ischemia-reperfusion injury, taurine also possesses anti-atherosclerotic, hypotensive, and antioxidant properties [2].

Taurine (2-aminoethanesulphonic acid), a sulphur-containing amino acid, is found in most mammalian tissues. Although it can be synthesized endogenously, the major source of taurine is from the diet. Taurine was found to exhibit diverse biological actions, including protection against ischemia-reperfusion injury, modulation of intracellular calcium concentration, and antioxidant, antiatherogenic and blood pressure-lowering effects. The present review will address the potential beneficial actions of taurine in congestive heart failure, hypertension, ischemic heart disease, atherosclerosis and diabetic cardiomyopathy. There is a wealth of experimental information and some clinical evidence available in the literature suggesting that taurine could be of benefit in cardiovascular disease of different etiologies. However, double-blind long-term clinical trials need to be conducted before taurine can be unequivocally recommended as a nutritional intervention for the prevention and/or treatment of cardiovascular disease[2].

Alterations in adipocyte characteristics are highly implicated in the pathology of obesity. In a recent article, we demonstrated that high-fat diet-induced obesity impairs lysosomal function, thereby suppressing autophagy in mice white adipose tissue. Taurine, an amino acid naturally contained in the normal diet and existing ubiquitously in tissues, has been reported to improve insulin resistance and chronic inflammation in animal models, but underlying mechanisms remain unclear. From these findings, we hypothesized that improvement of obese pathology by taurine may be mediated through recovery of autophagy. In matured 3T3-L1 mouse adipocytes, treatment with taurine-promoted autophagy. Moreover, taurine-induced nuclear translocation of transcription factor EB (TFEB), a master regulator of autophagy- and lysosome-related factors. As this translocation is regulated by several kinase pathways, including extracellular signal-related kinase 1 and 2 (ERK1/2) and mechanistic target of rapamycin protein kinase complex 1 (MTORC1), we examined related signaling elements. Consequently, taurine-reduced phosphorylation levels of ERK1/2 but did not alter the phosphorylation of MTORC1 pathway-associated adenosine monophosphate-activated protein kinase or ribosomal protein S6 kinase. Taken together, these results suggest that taurine may enhance TFEB nuclear translocation through ERK1/2 to accelerate autophagy. The effect discovered in this study may represent a novel mechanism for the improvement of obesity-related pathology by taurine[3].

Absorption, Distribution and Excretion
Studies on oral administration of taurine showed that its AUC, Cmax, and tmax values were dose-dependent. At doses ranging from 1 to 30 mg/kg, the AUC, Cmax, and tmax were 89–3452 mcg·min/L, 2–15.7 mcg·min/ml, and 15 min, respectively. Further studies in healthy individuals showed AUC, Cmax, and tmax ranging from 116–284.5 mg·h/L, 59–112.6 mg/L, and 1–2.5 h, respectively. Taurine flows and distributes in veins and arteries. Significant taurine release has been reported in visceral areas drained by the portal vein, indicating that the primary clearance route for taurine is the intestine. The enterohepatic circulation of taurine may explain its elimination pathway.
The distribution of taurine was studied in a two-compartment model. Results showed that the volume of distribution in the first compartment of mice was 299-353 ml/kg, and in the second compartment, it was 4608-8374 ml/kg. Further studies in healthy individuals indicated that the volume of distribution ranged from 19.8 to 40.7 L.
It has been reported that the clearance of orally administered taurine is dose-dependent: 11.7 ml min/kg at a dose of 1 mg/kg, 18.7 ml min/kg at a dose of 10 mg/kg, and 9.4 ml min/kg at a dose of 30 mg/kg. Further studies in healthy individuals indicated that the clearance ranged from 14 to 34.4 L/h.
Taurine is generally not completely reabsorbed by the kidneys; a portion of ingested taurine is excreted in the urine.
After ingestion, taurine is absorbed from the small intestine via the β-amino acid or taurine transport system…Taurine is transported to the liver via the portal vein circulation, where it is mostly bound to bile acids…These taurine conjugates are excreted via the bile route. Taurine not bound in the liver is distributed to various tissues of the body through systemic circulation.
Taurine is abundant in the brain, retina, myocardium, skeletal and smooth muscle, platelets, and neutrophils.
Human studies have shown that plasma taurine levels significantly increase 90 minutes after consuming taurine-rich foods and return to baseline levels within 180-270 minutes…
For more complete data on the absorption, distribution, and excretion of taurine (7 components), please visit the HSDB record page.

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Metabolism/Metabolites
Taurine can be metabolized by various organisms, forming different metabolites derived from its original form. In the human body, taurine is metabolized via two pathways: one is through the action of γ-glutamyltransferase 6 to produce 5-glutamyltaurine; the other is through the action of bile acid-CoA:amino acid N-acyltransferase to produce taurocholic acid. Taurine in the body comes from two sources: dietary sources and endogenous sources. In mammals, taurine is synthesized in various tissues; the main sites of synthesis are the liver, brain, and pancreas, with the α-zone of the islets of Langerhans being particularly prominent. Taurine is synthesized from cysteine and methionine through several steps, one of which requires pyridoxal-5-phosphate (vitamin B6) as a coenzyme for cysteine sulfinate decarboxylase. Research on the biosynthesis of taurine in species other than mammals is limited. The degree of taurine synthesis varies greatly among different species. In adult rats fed a standard laboratory diet, approximately 80% of their taurine is synthesized spontaneously, with the remainder obtained from food. However, rats can obtain all of their taurine through biosynthesis if needed, as the concentration of taurine in the tissues of rats fed a diet lacking taurine for extended periods did not decrease. Cats have low activity of cysteine sulfinate decarboxylase, the rate-limiting enzyme in taurine biosynthesis, and therefore must rely on dietary sources to maintain their taurine levels. Thus, taurine is an essential nutrient for cats. Taurocholic acid is a bile salt conjugate of taurine and bile acids, and is the main conjugate formed under the action of choyl-CoA N-acyltransferase. Among all vertebrates except mammals, taurine is the only amino acid that can combine with bile acids to form bile salts. In mammals, carnivores tend to bind only taurine, while other species tend to bind both taurine and glycine. High concentrations of taurine are found in the retina, liver, pancreas, central nervous system, and leukocytes. Taurine is most abundant in skeletal muscle and cardiac muscle, where it regulates intracellular Ca2+ concentration...

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Biological Half-Life
In healthy individuals, the plasma elimination half-life of taurine after oral administration is 0.7-1.4 hours.

Protein Binding
Taurine binds highly to plasma proteins and remains in the plasma. Interactions It can prevent ethanol-induced hypertension in rats. Animal studies have found that taurine can alleviate the pulmonary side effects (pulmonary fibrosis) of bleomycin. Three deaths occurred after consuming "energy" drinks and alcohol. Forensic examinations (including autopsies) showed no drugs in the deceased's bodies, and blood ethanol levels ranged from 0.59 to 0.87 ppm, but the cause of death was unknown. A serious adverse reaction occurred after consuming "energy" drinks and engaging in physical exercise: A 31-year-old, regularly training man consumed 750 ml of "energy" drink while participating in a 3000-meter race. He was diagnosed with rhabdomyolysis and acute renal failure with renal tubular necrosis a week after the race, and his overall condition deteriorated. For more complete data on the interactions of taurine (10 in total), please visit the HSDB records page.

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Non-human toxicity values
Oral LD50 in rats: >7000 mg/kg body weight
Subcutaneous LD50 in mice: 6000 mg/kg

[1]. Ripps H, Shen W. Review: taurine: a "very essential" amino acid. Mol Vis. 2012;18:2673-2686.

[2]. The potential health benefits of taurine in cardiovascular disease. Exp Clin Cardiol. 2008;13(2):57-65.

[3]. Taurine is an amino acid with the ability to activate autophagy in adipocytes. Amino Acids. 2018;50(5):527-535.

Large white crystals or white powder. Taurine is an aminosulfonic acid, a 2-amino derivative of ethanesulfonic acid. It is a naturally occurring amino acid derived from the metabolism of methionine and cysteine. Taurine is abundant in fish and meat and has been used as an oral supplement to treat diseases such as cystic fibrosis and hypertension. It is a human metabolite, antioxidant, mouse metabolite, Saccharomyces cerevisiae metabolite, Escherichia coli metabolite, glycine receptor agonist, nutrient, and free radical scavenger. It is the conjugate acid of 2-aminoethanesulfonic acid and also the zwitterionic tautomer of taurine. Taurine, chemically known as 2-aminoethanesulfonic acid, is one of the most abundant amino acids in many organs and plays an important role in vital biological processes. This conditionally essential amino acid can be synthesized by the human body or obtained from food, primarily through the consumption of fish and meat. Taurine-containing supplements were approved by the U.S. Food and Drug Administration (FDA) in 1984; they are hypertonic injectables composed of crystalline amino acids. Taurine is a metabolite of Escherichia coli (K12 strain, MG1655 strain) or is produced by E. coli. Taurine has been reported in Sargassum, fruit flies, and other organisms with relevant data. Taurine is a conditionally essential nutrient, crucial for the development of mammals. It is present in milk, but is primarily isolated from bovine bile and can strongly bind with bile acids. See also: Sodium taurate (its active ingredient); Potassium taurate (its active ingredient). Sodium laurate taurate (its active ingredient)... See more...

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Pharmaceutical Indications
Taurine-containing dietary supplements are indicated for nutritional support in infants and young children requiring total parenteral nutrition via central or peripheral routes. For pediatric patients who cannot receive nutritional supplementation via oral, gastrostomy, or jejunostomy routes, have impaired gastrointestinal absorption, or have significantly increased protein requirements, taurine-containing dietary supplements can prevent nitrogen and weight loss, or treat negative nitrogen balance.
FDA Label

Mechanism of Action

Dietary supplements containing taurine work by replenishing the body's missing nutrients. Taurine, as a single ingredient, has multiple functions, such as acting as a substrate for bile acid formation, regulating cell volume, regulating intracellular calcium ions, and protecting the central nervous system.
Therapeutic Uses

Taurine may be beneficial for some patients with congestive heart failure and hypertension. Animal and human studies have shown that taurine has a certain anti-atherosclerotic effect.
Therapeutic Classification (Veterinary): Used for the prevention of retinal degeneration in cats and for the prevention and treatment of taurine deficiency cardiomyopathy.
Taurine has been added to most infant formula since the mid-1980s.
Drug Warnings

Pregnant and breastfeeding women should avoid taking taurine supplements unless advised by a physician. Patients with congestive heart failure should use taurine under the guidance of a physician.
Taurine is contraindicated for those allergic to any ingredient in nutritional supplements containing taurine.
Pharmacodynamics Taurine-containing dietary supplements are a well-tolerated nitrogen source for nutritional support. Taking these supplements can regulate plasma amino acid concentrations, nitrogen balance, body weight, and serum protein concentrations to normal levels, thereby improving nutritional status. Taurine is an organic osmotic regulator involved in cell volume regulation and provides a substrate for bile acid formation. It plays a role in regulating intracellular free calcium concentration. Although taurine is one of the few amino acids that does not participate in protein synthesis, it is one of the most abundant amino acids in the brain, retina, muscle tissue, and other organs throughout the body. Taurine plays multiple functions in the central nervous system, ranging from development to cell protection. Taurine deficiency is closely associated with cardiomyopathy, renal dysfunction, developmental abnormalities, and severe damage to retinal neurons. Taurine is present in all ocular tissues, and quantitative analysis of rat ocular tissue extracts shows that taurine is the most abundant amino acid in the retina, vitreous body, lens, cornea, iris, and ciliary body. In the retina, taurine is essential for the development of photoreceptor cells and protects cells from stress-related neuronal damage and other pathological conditions. However, despite the many functional properties of taurine, the cellular and biochemical mechanisms by which it functions are not fully elucidated. Nevertheless, given its wide distribution, multiple cell-protective properties, and important role in cell development, nutrition, and survival, taurine is undoubtedly one of the most important substances in the human body. Interestingly, taurine meets many of the necessary criteria for what is considered a neurotransmitter, but there is no evidence of taurine-specific receptors in the vertebrate nervous system. In this report, we outline the functional properties of taurine, some consequences of taurine deficiency, and results from animal model studies that suggest that taurine may play a role in the treatment of epilepsy and diabetes. [1]

C2H7NO3S

125.1469

125.014

C, 19.20; H, 5.64; N, 11.19; O, 38.35; S, 25.62

107-35-7

Taurine-d4;342611-14-7;Taurine-13C2;70155-54-3;Taurine-13C2,15N;2483830-42-6

1123

White to off-white solid powder

1.5±0.1 g/cm3

>300 °C(lit.)

1.515

-2.46

2

4

2

7

120

0

XOAAWQZATWQOTB-UHFFFAOYSA-N

InChI=1S/C2H7NO3S/c3-1-2-7(4,5)6/h1-3H2,(H,4,5,6)

2-amino-ethanesulfonic acid

NSC-32428; β-Aminoethylsulfonic Acid; taurine; 2-aminoethanesulfonic acid; 107-35-7; Ethanesulfonic acid, 2-amino-; tauphon; L-Taurine; 2-Aminoethylsulfonic acid; 2-Sulfoethylamine; NSC 32428

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

H2O : ~25 mg/mL (~199.76 mM)
DMSO : ~1 mg/mL (~7.99 mM)

Solubility in Formulation 1: 12.5 mg/mL (99.88 mM) in PBS (add these co-solvents sequentially from left to right, and one by one), clear solution; with sonication (<60°C).

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 (Please use freshly prepared in vivo formulations for optimal results.)