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Taurine has been approved for the treatment of congestive heart failure in Japan for several years. In addition to relieving breathlessness with exertion and fluid retention, it can also reduce or completely eliminate the need for CHF drugs such as digoxin. Although increasing diuresis and improving contractile force are beneficial, perhaps the most important effect of taurine on CHF has to do with inhibition of norepinephrine and angiotensin II. These molecules decrease the contractile ability of the heart by increasing afterload pressure and other effects. Taurine has been found to increase exercise capacity of CHF patients and may prolong lifespan.7
Hypertension. Taurine has proved to be effective in preventing hypertension from developing in several animal models. Various factors have been identified, including decreases in oxidative stress, sympathetic tone, and inflammation, combined with improved kidney function and Ca2+ homeostasis.7 Two human clinical studies also found benefits from taurine for hypertension. Katakawa reported improved endothelial function which he attributed to taurine’s effects in reducing oxidative stress.10 In a study by Sun, 120 prehypertensive patients received 1.6 grams of taurine per day, or placebo, for a period of 12 weeks. Patients receiving taurine had decreases in both systolic and diastolic BP, compared to patients in the placebo wing of the trial, who experienced no decrease in BP. The higher the initial blood pressure, the greater improvement was seen with taurine supplementation.11.
Atherogenesis. Taurine has several beneficial effects on vascular tissue, which inhibit or reverse the atherosclerotic process. These include inhibition of apoptosis, inflammation, and oxidative stress, as mentioned above. Taurine can also reverse intima medial thickening and arterial stiffness, which probably account for some part of improvements in blood pressure.
Taurine inhibits proliferation of vascular smooth muscle cells in culture. Smooth muscle cell proliferation is a part of the cascade of events leading to intimal media thickening and the development of atherosclerotic plaques. Taurine is also important to the health of vascular endothelial cells, decreasing apoptosis and protecting them through its anti-inflammatory and antioxidant activity and the modulation of intracellular calcium. Dysfunction in endothelial cells cultured from smokers was attenuated by the addition of taurine, which upregulated the expression of NO synthase.12
Stroke. Stroke is a leading cause of death and disability. A main contributor to neuronal death during stroke is the large accumulation of glutamate in the synaptic clefts as glutamate uptake is compromised by lack of ATP to glutamate transporters. This ultimately results in influxes of Ca2+, compromised mitochondrial function and the generation of ROS, all of which contribute to cellular distruction.13 Taurine helps protect cells from the toxic effects of excess glutamate by reducing the overload of calcium and reducing oxidative stress.7
What Else Is Taurine Good For?
This article is focused on the cardiovascular benefits of taurine, but if we are considering longevity, it is worth mentioning a few other conditions in which taurine can be useful. A lack of taurine contributes to a broad range of pathologies, including renal dysfunction, pancreatic βcell dysfunction, and decreased vision to the loss of photoreceptors in the retina.8 Supplemental taurine reduces markers for inflammation in obesity and may improve lean body mass.7
Diabetes. Schaffer and Kim assert, “There is overwhelming evidence that taurine therapy reduces pathology associated with diabetes, obesity and the metabolic syndrome.”7 Patients with Type I diabetes have low plasma and platelet taurine levels.7 Taurine decreases advanced glycation end products (AGE) and lipid peroxidation in the kidney, thus improving diabetic nephropathy. 8
Mitochondrial Disease. MELAS (Mitochondrial Encephalomyopathy, Lactic Acidosis, and Stroke-like episodes) is a mitochondrial disease that shares characteristic symptoms with taurine deficiency.13 Supplementing MELAS patients with taurine has been helpful. In one such case a 29-year-old woman who had no response to standard pharmaceutical therapy for epileptic and stroke-like episodes, had a complete cessation of these events shortly after starting on oral taurine. In a second case, a 21-year-old male was diagnosed with MELAS and put on anticonvulsant therapy that did little to decrease his stroke-like episodes, which included visual loss and sensory aphasia. Upon starting taurine supplementation, the episodes ceased. In both cases the patients’ serum levels of taurine increased by 5- and 10-fold, respectively.7 Schaffer reports that taurine therapy also returns mitochondrial respiratory function to normal in these patients.
Taurine and the Eye. All ocular tissues contain taurine, although the retina has the highest levels.8 In a normal retina, the concentration of taurine is at least 10 times that of any other amino acid.8 Taurine is required for the survival of retinal ganglion cells.7 Taurine also protects rod outer segments from photic damage.8 Severe degenerative changes to photoreceptors are common in animals that do not synthesize adequate levels of taurine, including cats, monkeys, and humans, if they do not get adequate dietary taurine.8
Taurine in the Brain. No brain region that has been tested fails to contain or uptake taurine: “At each of these sites, there is evidence of taurine’s ability to ameliorate certain forms of neuropathology.”8 Taurine is a weak agonist of the GABAA, glycine, and NMDA receptors.7
While taurine does seem to have some mild anticonvulsant effects, those effects are inconsistent.8 In human clinical trials, about one third of patients had a reduction in epileptic seizures with taurine administration.7
Interestingly, taurine meets all criteria but one for the definition of being a neurotransmitter. Those criteria are 1) the enzymes and biochemistry necessary for biosynthesis exist in presynaptic neurons; 2) it is released by presynaptic depolarization and affects post synaptic cells, and the mechanism for doing that is calcium-dependent; 3) its action is terminated by degradation or re-uptake, and there is an antagonist; and 4) there is a specific receptor on post-synaptic cells. Of these criteria, taurine lacks only the identification of a post-synaptic receptor.8
Sarcopenia. Taurine is a common ingredient in nutritional formulas intended to improve sports performance and muscle development, and there are a number of studies that show improvement in exercise performance with taurine supplementation. Less researched, but germane to the issue of longevity, is whether sarcopenia in older men and women can be reversed or slowed with the use of taurine. Taurine plays a role in regulating two pathways involved in the degradation of muscle proteins and myocyte death, the calpain pathway and the capsase pathway. Both are calcium-dependent and taurine’s regulatory effect on intracellular calcium concentrations helps keep these pathways in check. Taurine also appears to influence protein catabolism in aging muscle via the stimulation of inhibitory pathways.14
Dietary Sources of Taurine
Taurine is most abundant in shellfish such as scallops, oysters, clams, mussels, prawns, and octopus. It is also high in many saltwater fish. Taurine levels in freshwater fish were not found, but one source suggested that fresh had a higher capacity for synthesizing taurine than saltwater fish, so presumably fish of any kind would provide decent levels of taurine. Red meats contain some taurine, although significantly less than fish and shellfish. Best meat sources of taurine are dark meat of turkey and chicken. Dairy products and eggs contain relatively little taurine and one researcher found no detectable levels on taurine in legumes, nuts, or vegetables.15
