Serum Taurine and Stroke Risk in Women: A Prospective, Nested Case-Control Study

Unveiling taurine's protective role in ischemic stroke: insights from bidirectional Mendelian randomization and LC-MS/MS analysis

Ischemic stroke remains a leading cause of mortality and disability globally, emphasizing the urgent need for innovative preventative and therapeutic strategies. Taurine, a critical amino sulfonic acid, has garnered attention for its neuroprotective effects, yet its precise role in ischemic stroke remains elusive. This study utilized a bidirectional Mendelian Randomization (MR) approach to explore the causal relationship between plasma taurine levels and ischemic stroke risk, employing genome-wide association study (GWAS) datasets. In parallel, a novel high-sensitivity liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed to quantify plasma taurine levels in ischemic stroke patients and healthy controls. Our findings reveal a significant inverse association between taurine levels and stroke risk, with IVW analysis showing beta = -0.001 and P = 0.0085. Furthermore, LC-MS/MS analysis demonstrated that plasma taurine levels in patients with ischemic stroke were notably lower at 36.07 ± 5.37 μmol/L compared to controls at 108.66 ± 25.11 μmol/L, confirming taurine's potential as a protective factor. These results suggest taurine as a promising biomarker and therapeutic target for stroke prevention and recovery. This study not only highlights the importance of taurine in cerebrovascular health but also provides a foundation for personalized intervention strategies.

Association of gut microbiota and immunometabolic profiles with ischemic stroke severity

This study investigates the influence of three regulators of human homeostasis-intestinal microbiota, immune profile, and circulating metabolites-on stroke severity. We conducted a study involving 33 patients with mild/moderate stroke (MS) and 32 with severe stroke (SS), all assessed during the acute phase (first 24 h). The analysis focused on microbiota composition (45 patients), serum metabolomics and inflammatory markers (20 patients). The patients with SS exhibited more pronounced insulin resistance associated with increased levels of branched-chain amino acids and their metabolites. SS patients showed an increase in inflammatory cytokines IL-6 and TNF-α, and surprisingly an increase in IL-10 and butyrate which are anti-inflammatory. SS patients also displayed a distinct microbiota profile, with statistically significant differences in β-diversity compared to the MS group, notably a higher prevalence of Pseudomonadota (formerly Proteobacteria). In summary, our data indicate that patients with SS, compared to those with MS, are characterized by a more inflammatory and insulin-resistant state, associated with three key regulators: microbiota, metabolites, and interleukins. These findings provide new insights into the regulatory components of the gut-brain axis, which could be developed into cost-effective and widely accessible therapies for SS.

Taurine and Its Derivatives: Analysis of the Inhibitory Effect on Platelet Function and Their Antithrombotic Potential

Taurine is a semi-essential, the most abundant free amino acid in the human body, with a six times higher concentration in platelets than any other amino acid. It is highly beneficial for the organism, has many therapeutic actions, and is currently approved for heart failure treatment in Japan. Taurine has been repeatedly reported to elicit an inhibitory action on platelet activation and aggregation, sustained by in vivo, ex vivo, and in vitro animal and human studies. Taurine showed effectiveness in several pathologies involving thrombotic diathesis, such as diabetes, traumatic brain injury, acute ischemic stroke, and others. As human prospective studies on thrombosis outcome are very difficult to carry out, there is an obvious need to validate existing findings, and bring new compelling data about the mechanisms underlying taurine and derivatives antiplatelet action and their antithrombotic potential. Chloramine derivatives of taurine proved a higher stability and pronounced selectivity for platelet receptors, raising the assumption that they could represent future potential antithrombotic agents. Considering that taurine and its analogues display permissible side effects, along with the need of finding new, alternative antithrombotic drugs with minimal side effects and long-term action, the potential clinical relevance of this fascinating nutrient and its derivatives requires further consideration.

Plasma Sulfur Amino Acids and Risk of Cerebrovascular Diseases: A Nested Case-Control Study in the EPIC-Norfolk Cohort

BACKGROUND AND PURPOSE

B-vitamin supplements lower circulating concentrations of homocysteine and may reduce stroke incidence. Homocysteine concentrations are associated with the incidence of stroke but other sulfur-containing compounds in the related metabolic pathway have not yet been investigated for an association with incident cerebrovascular diseases.

METHODS

Nested within the EPIC (European Prospective Investigation Into Cancer and Nutrition)-Norfolk cohort, we established a case-control study with 480 incident cases of cerebrovascular diseases and 480 controls matched by age, sex, and year of baseline examination (1993-1997). Using baseline plasma samples, we assayed sulfur-containing compounds including methionine, homocysteine, cystathionine, cysteine, glutathione, and taurine with liquid chromatography-tandem mass spectrometry. We examined the association of concentrations of each of the compounds and the ratio of methionine to homocysteine (representing activity of one-carbon metabolism) with risk of incident cerebrovascular diseases, adjusted for potential confounders.

RESULTS

Plasma methionine and the methionine/homocysteine ratio were inversely associated with risk of cerebrovascular diseases, with odds ratios per 1 SD of 0.83 (95% CI, 0.72-0.96) and 0.82 (95% CI, 0.71-0.95), respectively. The association of methionine remained significant after adjustment for homocysteine. None of the other examined compounds was significantly associated with incident cerebrovascular diseases.

CONCLUSIONS

These findings suggest that greater availability of methionine, an essential amino acid, may play a role in the prevention of cerebrovascular diseases and explain the previously recognized link between elevated homocysteine and stroke. Further research is needed to determine causation and the potential of circulating methionine as a target in cerebrovascular disease prevention.

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

Taurine is a sulfur-containing amino acid and known as semi-essential in mammals and is produced chiefly by the liver and kidney. It presents in different organs, including retina, brain, heart and placenta and demonstrates extensive physiological activities within the body. In the several disease models, it attenuates inflammation- and oxidative stress-mediated injuries. Taurine also modulates ER stress, Ca2+ homeostasis and neuronal activity at the molecular level as part of its broader roles. Different cellular processes such as energy metabolism, gene expression, osmosis and quality control of protein are regulated by taurine. In addition, taurine displays potential ameliorating effects against different neurological disorders such as neurodegenerative diseases, stroke, epilepsy and diabetic neuropathy and protects against injuries and toxicities of the nervous system. Several findings demonstrate its therapeutic role against neurodevelopmental disorders, including Angelman syndrome, Fragile X syndrome, sleep-wake disorders, neural tube defects and attention-deficit hyperactivity disorder. Considering current biopharmaceutical limitations, developing novel delivery approaches and new derivatives and precursors of taurine may be an attractive option for treating neurological disorders. Herein, we present an overview on the therapeutic potential of taurine against neurological disorders and highlight clinical studies and its molecular mechanistic roles. This article also addresses the neuropharmacological potential of taurine analogs.

Effects and Mechanisms of Taurine as a Therapeutic Agent

Taurine is an abundant, β-amino acid with diverse cytoprotective activity. In some species, taurine is an essential nutrient but in man it is considered a semi-essential nutrient, although cells lacking taurine show major pathology. These findings have spurred interest in the potential use of taurine as a therapeutic agent. The discovery that taurine is an effective therapy against congestive heart failure led to the study of taurine as a therapeutic agent against other disease conditions. Today, taurine has been approved for the treatment of congestive heart failure in Japan and shows promise in the treatment of several other diseases. The present review summarizes studies supporting a role of taurine in the treatment of diseases of muscle, the central nervous system, and the cardiovascular system. In addition, taurine is extremely effective in the treatment of the mitochondrial disease, mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS), and offers a new approach for the treatment of metabolic diseases, such as diabetes, and inflammatory diseases, such as arthritis. The review also addresses the functions of taurine (regulation of antioxidation, energy metabolism, gene expression, ER stress, neuromodulation, quality control and calcium homeostasis) underlying these therapeutic actions.

Diet-induced glucose homeostasis dysregulation is enhanced by taurine supplementation in ovariectomized mice

Low levels of estrogens are associated with obesity-related comorbidities. Mice with lower levels of estrogens are thereby more sensitive to the effects of a high-fat-diet (HFD) for the development of glucose intolerance and insulin resistance. Studies in vivo have demonstrated that taurine (TAU) supplementation prevents glucose and insulin resistance. Thus, we aimed to investigate the potential beneficial effects of TAU supplementation on glucose homeostasis of mice with low levels of estrogens fed with a HFD. 3-month-old female C57BL/6J mice underwent bilateral ovariectomy (OVX). After 1 week of recovery, mice were divided into 4 groups and either received: a standard chow diet (OVXC), chow diet plus drinking water enriched with 3% of TAU (OVXCT), HFD (OVXH), and HFD plus supplementation of TAU (OVXHT) for 14 weeks. Exposure to the HFD increased adiposity and plasma levels of glucose and insulin. Contrary to our prediction, the addition of TAU enhanced the deleterious effects of the HFD. Glucose and insulin tolerance tests (ipGTT and ipITT) indicated that mice maintained on the HFD + TAU had worse glucose intolerance and insulin resistance that was linked to lower insulin signaling in skeletal muscle and liver. Insulin secretion of isolated pancreatic islets of OVXH mice was higher than OVXC, and the addition of TAU associated with a HFD did not modulate insulin secretion, suggesting a failure of pancreatic β cells of OVXHT mice. These results suggest that despite the beneficial reports of TAU, it should be used cautiously in situations where the levels of estrogens are low.