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Physiological Reviews Oct 2013Carnosine (β-alanyl-l-histidine) was discovered in 1900 as an abundant non-protein nitrogen-containing compound of meat. The dipeptide is not only found in skeletal... (Review)
Review
Carnosine (β-alanyl-l-histidine) was discovered in 1900 as an abundant non-protein nitrogen-containing compound of meat. The dipeptide is not only found in skeletal muscle, but also in other excitable tissues. Most animals, except humans, also possess a methylated variant of carnosine, either anserine or ophidine/balenine, collectively called the histidine-containing dipeptides. This review aims to decipher the physiological roles of carnosine, based on its biochemical properties. The latter include pH-buffering, metal-ion chelation, and antioxidant capacity as well as the capacity to protect against formation of advanced glycation and lipoxidation end-products. For these reasons, the therapeutic potential of carnosine supplementation has been tested in numerous diseases in which ischemic or oxidative stress are involved. For several pathologies, such as diabetes and its complications, ocular disease, aging, and neurological disorders, promising preclinical and clinical results have been obtained. Also the pathophysiological relevance of serum carnosinase, the enzyme actively degrading carnosine into l-histidine and β-alanine, is discussed. The carnosine system has evolved as a pluripotent solution to a number of homeostatic challenges. l-Histidine, and more specifically its imidazole moiety, appears to be the prime bioactive component, whereas β-alanine is mainly regulating the synthesis of the dipeptide. This paper summarizes a century of scientific exploration on the (patho)physiological role of carnosine and related compounds. However, far more experiments in the fields of physiology and related disciplines (biology, pharmacology, genetics, molecular biology, etc.) are required to gain a full understanding of the function and applications of this intriguing molecule.
Topics: Animals; Brain; Cardiovascular Physiological Phenomena; Carnosine; Dipeptidases; Disease Models, Animal; Female; Humans; Male; Muscle, Skeletal
PubMed: 24137022
DOI: 10.1152/physrev.00039.2012 -
Journal of the International Society of... 2015The International Society of Sports Nutrition (ISSN) provides an objective and critical review of the mechanisms and use of beta-alanine supplementation. Based on the... (Review)
Review
The International Society of Sports Nutrition (ISSN) provides an objective and critical review of the mechanisms and use of beta-alanine supplementation. Based on the current available literature, the conclusions of the ISSN are as follows: 1) Four weeks of beta-alanine supplementation (4-6 g daily) significantly augments muscle carnosine concentrations, thereby acting as an intracellular pH buffer; 2) Beta-alanine supplementation currently appears to be safe in healthy populations at recommended doses; 3) The only reported side effect is paraesthesia (tingling), but studies indicate this can be attenuated by using divided lower doses (1.6 g) or using a sustained-release formula; 4) Daily supplementation with 4 to 6 g of beta-alanine for at least 2 to 4 weeks has been shown to improve exercise performance, with more pronounced effects in open end-point tasks/time trials lasting 1 to 4 min in duration; 5) Beta-alanine attenuates neuromuscular fatigue, particularly in older subjects, and preliminary evidence indicates that beta-alanine may improve tactical performance; 6) Combining beta-alanine with other single or multi-ingredient supplements may be advantageous when supplementation of beta-alanine is high enough (4-6 g daily) and long enough (minimum 4 weeks); 7) More research is needed to determine the effects of beta-alanine on strength, endurance performance beyond 25 min in duration, and other health-related benefits associated with carnosine.
Topics: Carnosine; Dietary Supplements; Dose-Response Relationship, Drug; Exercise; Fatigue; Humans; Hydrogen-Ion Concentration; Muscle, Skeletal; Neuromuscular Agents; Recommended Dietary Allowances; Sports Nutritional Physiological Phenomena; Toxicity Tests; beta-Alanine
PubMed: 26175657
DOI: 10.1186/s12970-015-0090-y -
Nutrients Apr 2023The dipeptide carnosine is a physiologically important molecule in the human body, commonly found in skeletal muscle and brain tissue. Beta-alanine is a limiting... (Review)
Review
The dipeptide carnosine is a physiologically important molecule in the human body, commonly found in skeletal muscle and brain tissue. Beta-alanine is a limiting precursor of carnosine and is among the most used sports supplements for improving athletic performance. However, carnosine, its metabolite -acetylcarnosine, and the synthetic derivative zinc-L-carnosine have recently been gaining popularity as supplements in human medicine. These molecules have a wide range of effects-principally with anti-inflammatory, antioxidant, antiglycation, anticarbonylation, calcium-regulatory, immunomodulatory and chelating properties. This review discusses results from recent studies focusing on the impact of this supplementation in several areas of human medicine. We queried PubMed, Web of Science, the National Library of Medicine and the Cochrane Library, employing a search strategy using database-specific keywords. Evidence showed that the supplementation had a beneficial impact in the prevention of sarcopenia, the preservation of cognitive abilities and the improvement of neurodegenerative disorders. Furthermore, the improvement of diabetes mellitus parameters and symptoms of oral mucositis was seen, as well as the regression of esophagitis and taste disorders after chemotherapy, the protection of the gastrointestinal mucosa and the support of eradication treatment. However, in the areas of senile cataracts, cardiovascular disease, schizophrenia and autistic disorders, the results are inconclusive.
Topics: Humans; Carnosine; Antioxidants; Dietary Supplements; Dipeptides; Muscle, Skeletal; beta-Alanine
PubMed: 37049610
DOI: 10.3390/nu15071770 -
The Journal of Nutrition Oct 2020Histidine is a dietary essential amino acid because it cannot be synthesized in humans. The WHO/FAO requirement for adults for histidine is 10 mg · kg body weight-1 ·... (Review)
Review
Histidine is a dietary essential amino acid because it cannot be synthesized in humans. The WHO/FAO requirement for adults for histidine is 10 mg · kg body weight-1 · d-1. Histidine is required for synthesis of proteins. It plays particularly important roles in the active site of enzymes, such as serine proteases (e.g., trypsin) where it is a member of the catalytic triad. Excess histidine may be converted to trans-urocanate by histidine ammonia lyase (histidase) in liver and skin. UV light in skin converts the trans form to cis-urocanate which plays an important protective role in skin. Liver is capable of complete catabolism of histidine by a pathway which requires folic acid for the last step, in which glutamate formiminotransferase converts the intermediate N-formiminoglutamate to glutamate, 5,10 methenyl-tetrahydrofolate, and ammonia. Inborn errors have been recognized in all of the catabolic enzymes of histidine. Histidine is required as a precursor of carnosine in human muscle and parts of the brain where carnosine appears to play an important role as a buffer and antioxidant. It is synthesized in the tissue by carnosine synthase from histidine and β-alanine, at the expense of ATP hydrolysis. Histidine can be decarboxylated to histamine by histidine decarboxylase. This reaction occurs in the enterochromaffin-like cells of the stomach, in the mast cells of the immune system, and in various regions of the brain where histamine may serve as a neurotransmitter.
Topics: Brain; Carnosine; Glutamic Acid; Histamine; Histidine; Histidine Ammonia-Lyase; Humans; Liver; Muscles; Skin
PubMed: 33000155
DOI: 10.1093/jn/nxaa079 -
Amino Acids Mar 2020Taurine (a sulfur-containing β-amino acid), creatine (a metabolite of arginine, glycine and methionine), carnosine (a dipeptide; β-alanyl-L-histidine), and... (Review)
Review
Taurine (a sulfur-containing β-amino acid), creatine (a metabolite of arginine, glycine and methionine), carnosine (a dipeptide; β-alanyl-L-histidine), and 4-hydroxyproline (an imino acid; also often referred to as an amino acid) were discovered in cattle, and the discovery of anserine (a methylated product of carnosine; β-alanyl-1-methyl-L-histidine) also originated with cattle. These five nutrients are highly abundant in beef, and have important physiological roles in anti-oxidative and anti-inflammatory reactions, as well as neurological, muscular, retinal, immunological and cardiovascular function. Of particular note, taurine, carnosine, anserine, and creatine are absent from plants, and hydroxyproline is negligible in many plant-source foods. Consumption of 30 g dry beef can fully meet daily physiological needs of the healthy 70-kg adult human for taurine and carnosine, and can also provide large amounts of creatine, anserine and 4-hydroxyproline to improve human nutrition and health, including metabolic, retinal, immunological, muscular, cartilage, neurological, and cardiovascular health. The present review provides the public with the much-needed knowledge of nutritionally and physiologically significant amino acids, dipeptides and creatine in animal-source foods (including beef). Dietary taurine, creatine, carnosine, anserine and 4-hydroxyproline are beneficial for preventing and treating obesity, cardiovascular dysfunction, and ageing-related disorders, as well as inhibiting tumorigenesis, improving skin and bone health, ameliorating neurological abnormalities, and promoting well being in infants, children and adults. Furthermore, these nutrients may promote the immunological defense of humans against infections by bacteria, fungi, parasites, and viruses (including coronavirus) through enhancing the metabolism and functions of monocytes, macrophages, and other cells of the immune system. Red meat (including beef) is a functional food for optimizing human growth, development and health.
Topics: Animals; Anserine; Carnosine; Cattle; Creatine; Humans; Hydroxyproline; Nutritive Value; Red Meat; Taurine
PubMed: 32072297
DOI: 10.1007/s00726-020-02823-6 -
Molecular Medicine Reports Jan 2023Carnosine is a vital endogenous dipeptide that has anti‑inflammatory, antiaging, anti‑crosslinking, antitumor and immune regulatory effects. Numerous cell and animal... (Review)
Review
Carnosine is a vital endogenous dipeptide that has anti‑inflammatory, antiaging, anti‑crosslinking, antitumor and immune regulatory effects. Numerous cell and animal model studies have proved that carnosine and its compounds promote the proliferation and differentiation of osteoblasts, inhibit osteoclasts and protect chondrocytes. They also regulate the cell cycle of bone progenitor cells and the differentiation of bone marrow mesenchymal stem cells, accelerate fracture healing, delay bone tumor development and ameliorate osteopenia induced by estrogen deficiency or disuse. The correlations between carnosine and activation signal molecules, pluripotent differentiation of bone marrow mesenchymal stem cells and interaction between bone cells are unclear. However, studies have proved that carnosine and its compounds have benefits in preventing and treating specific bone diseases. This makes them potential agents for the treatment of osteoporosis and bone tumors. The present review summarized the existing research on carnosine and its compounds in bone cells and tissue. It focused on the physiological function of carnosine and its compounds in the bone and their effect on bone metabolism‑related diseases, thus providing support for developing new strategies for targeted therapy.
Topics: Animals; Carnosine; Osteoclasts; Mesenchymal Stem Cells; Osteoblasts; Cell Differentiation
PubMed: 36416346
DOI: 10.3892/mmr.2022.12899 -
European Journal of Sport Science Feb 2019Carnosine was originally discovered in skeletal muscle, where it exists in larger amounts than in other tissues. The majority of research into the physiological roles of... (Review)
Review
Carnosine was originally discovered in skeletal muscle, where it exists in larger amounts than in other tissues. The majority of research into the physiological roles of carnosine have been conducted on skeletal muscle. Given this and the potential for muscle carnosine content to be increased with supplementation, there is now a large body of research examining the ergogenic effects (or otherwise) of carnosine. More recent research, however, points towards a potential for carnosine to exert a wider range of physiological effects in other tissues, including the brain, heart, pancreas, kidney and cancer cells. Taken together, this is suggestive of a potential for carnosine to have therapeutic benefits in health and disease, although this is by no means without complication. Herein, we will provide a review of the current literature relating to the potential therapeutic effects of carnosine in health and disease.
Topics: Acute Kidney Injury; Aging; Brain; Carnosine; Cognition; Diabetes Mellitus, Type 2; Heart; Humans; Kidney; Muscle, Skeletal; Neoplasms; Neurodegenerative Diseases; Pancreas; Performance-Enhancing Substances
PubMed: 29502490
DOI: 10.1080/17461391.2018.1444096 -
Amino Acids Jul 2012Due to the well-defined role of β-alanine as a substrate of carnosine (a major contributor to H+ buffering during high-intensity exercise), β-alanine is fast becoming... (Meta-Analysis)
Meta-Analysis
Due to the well-defined role of β-alanine as a substrate of carnosine (a major contributor to H+ buffering during high-intensity exercise), β-alanine is fast becoming a popular ergogenic aid to sports performance. There have been several recent qualitative review articles published on the topic, and here we present a preliminary quantitative review of the literature through a meta-analysis. A comprehensive search of the literature was employed to identify all studies suitable for inclusion in the analysis; strict exclusion criteria were also applied. Fifteen published manuscripts were included in the analysis, which reported the results of 57 measures within 23 exercise tests, using 18 supplementation regimes and a total of 360 participants [174, β-alanine supplementation group (BA) and 186, placebo supplementation group (Pla)]. BA improved (P=0.002) the outcome of exercise measures to a greater extent than Pla [median effect size (IQR): BA 0.374 (0.140-0.747), Pla 0.108 (-0.019 to 0.487)]. Some of that effect might be explained by the improvement (P=0.013) in exercise capacity with BA compared to Pla; no improvement was seen for exercise performance (P=0.204). In line with the purported mechanisms for an ergogenic effect of β-alanine supplementation, exercise lasting 60-240 s was improved (P=0.001) in BA compared to Pla, as was exercise of >240 s (P=0.046). In contrast, there was no benefit of β-alanine on exercise lasting <60 s (P=0.312). The median effect of β-alanine supplementation is a 2.85% (-0.37 to 10.49%) improvement in the outcome of an exercise measure, when a median total of 179 g of β-alanine is supplemented.
Topics: Athletic Performance; Carnosine; Dietary Supplements; Exercise; Exercise Test; Humans; Performance-Enhancing Substances; Physical Endurance; beta-Alanine
PubMed: 22270875
DOI: 10.1007/s00726-011-1200-z -
Nutrients Jan 2018Zinc (Zn) is abundantly present in the brain, and accumulates in the synaptic vesicles. Synaptic Zn is released with neuronal excitation, and plays essential roles in... (Review)
Review
Zinc (Zn) is abundantly present in the brain, and accumulates in the synaptic vesicles. Synaptic Zn is released with neuronal excitation, and plays essential roles in learning and memory. Increasing evidence suggests that the disruption of Zn homeostasis is involved in various neurodegenerative diseases including Alzheimer's disease, a vascular type of dementia, and prion diseases. Our and other numerous studies suggest that carnosine (β-alanyl histidine) is protective against these neurodegenerative diseases. Carnosine is an endogenous dipeptide abundantly present in the skeletal muscles and in the brain, and has numerous beneficial effects such as antioxidant, metal chelating, anti-crosslinking, and anti-glycation activities. The complex of carnosine and Zn, termed polaprezinc, is widely used for Zn supplementation therapy and for the treatment of ulcers. Here, we review the link between Zn and these neurodegenerative diseases, and focus on the neuroprotective effects of carnosine. We also discuss the carnosine level in various foodstuffs and beneficial effects of dietary supplementation of carnosine.
Topics: Alzheimer Disease; Amyloidogenic Proteins; Animals; Antioxidants; Brain; Carnosine; Chelating Agents; Dementia, Vascular; Dietary Supplements; Disease Models, Animal; Homeostasis; Humans; Neurodegenerative Diseases; Neuroprotective Agents; Prion Diseases; Zinc
PubMed: 29382141
DOI: 10.3390/nu10020147 -
Nutrients Feb 2023β-alanine is a nonessential amino acid that combines with the amino acid histidine to form the intracellular dipeptide carnosine, an important intracellular buffer.... (Review)
Review
β-alanine is a nonessential amino acid that combines with the amino acid histidine to form the intracellular dipeptide carnosine, an important intracellular buffer. Evidence has been well established on the ability of β-alanine supplementation to enhance anaerobic skeletal muscle performance. As a result, β-alanine has become one of the more popular supplements used by competitive athletes. These same benefits have also been reported in soldiers. Evidence accumulated over the last few years has suggested that β-alanine can result in carnosine elevations in the brain, which appears to have broadened the potential effects that β-alanine supplementation may have on soldier performance and health. Evidence suggests that β-alanine supplementation can increase resilience to post-traumatic stress disorder, mild traumatic brain injury and heat stress. The evidence regarding cognitive function is inconclusive but may be more of a function of the stressor that is applied during the assessment period. The potential benefits of β-alanine supplementation on soldier resiliency are interesting but require additional research using a human model. The purpose of this review is to provide an overview of the physiological role of β-alanine and why this nutrient may enhance soldier performance.
Topics: Humans; Carnosine; Exercise; Military Personnel; Dietary Supplements; beta-Alanine; Cognition; Muscle, Skeletal
PubMed: 36839397
DOI: 10.3390/nu15041039