Antioxidants are compounds that inhibit oxidation, a chemical reaction that can produce free radicals. Autoxidation leads to degradation of organic compounds, including living matter. Antioxidants are frequently added to industrial products, such as polymers, fuels, and lubricants, to extend their usable lifetimes. Food are also treated with antioxidants to forestall spoilage, in particular the rancidification of oils and fats. In cells, antioxidants such as glutathione, mycothiol or bacillithiol, and enzyme systems like superoxide dismutase, can prevent damage from oxidative stress.
Histidine (symbol His or H) is an essential amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated –NH3+ form under biological conditions), a carboxylic acid group (which is in the deprotonated –COO− form under biological conditions), and an imidazole side chain (which is partially protonated), classifying it as a positively charged amino acid at physiological pH. Initially thought essential only for infants, it has now been shown in longer-term studies to be essential for adults also. It is encoded by the codons CAU and CAC.
Creatine is an organic compound with the nominal formula (H2N)(HN)CN(CH3)CH2CO2H. It exists in various tautomers in solutions. Creatine is found in vertebrates where it facilitates recycling of adenosine triphosphate (ATP), primarily in muscle and brain tissue. Recycling is achieved by converting adenosine diphosphate (ADP) back to ATP via donation of phosphate groups. Creatine also acts as a buffer.
A dipeptide is an organic compound derived from two amino acids. The constituent amino acids can be the same or different. When different, two isomers of the dipeptide are possible, depending on the sequence. Several dipeptides are physiologically important, and some are both physiologically and commercially significant. A well known dipeptide is aspartame, an artificial sweetener.
β-Alanine is a naturally occurring beta amino acid, which is an amino acid in which the amino group is attached to the β-carbon instead of the more usual α-carbon for alanine (α-alanine). The IUPAC name for β-alanine is 3-aminopropanoic acid. Unlike its counterpart α-alanine, β-alanine has no stereocenter.
Bodybuilding supplements are dietary supplements commonly used by those involved in bodybuilding, weightlifting, mixed martial arts, and athletics for the purpose of facilitating an increase in lean body mass. Bodybuilding supplements may contain ingredients that are advertised to increase a person's muscle, body weight, athletic performance, and decrease a person's percent body fat for desired muscle definition. Among the most widely used are high protein drinks, pre-workout blends, branched-chain amino acids (BCAA), glutamine, arginine, essential fatty acids, creatine, HMB, whey protein, ZMA, and weight loss products. Supplements are sold either as single ingredient preparations or in the form of "stacks" – proprietary blends of various supplements marketed as offering synergistic advantages.
Anserine (β-alanyl-3-methylhistidine) is a dipeptide containing β-alanine and 3-methylhistidine. Anserine is a derivative of carnosine, which has been methylated.
β-Hydroxy β-methylbutyric acid (HMB), otherwise known as its conjugate base, β-hydroxyβ-methylbutyrate, is a naturally produced substance in humans that is used as a dietary supplement and as an ingredient in certain medical foods that are intended to promote wound healing and provide nutritional support for people with muscle wasting due to cancer or HIV/AIDS. In healthy adults, supplementation with HMB has been shown to increase exercise-induced gains in muscle size, muscle strength, and lean body mass, reduce skeletal muscle damage from exercise, improve aerobic exercise performance, and expedite recovery from exercise. Medical reviews and meta-analyses indicate that HMB supplementation also helps to preserve or increase lean body mass and muscle strength in individuals experiencing age-related muscle loss. HMB produces these effects in part by stimulating the production of proteins and inhibiting the breakdown of proteins in muscle tissue. No adverse effects from long-term use as a dietary supplement in adults have been found.
A branched-chain amino acid (BCAA) is an amino acid having an aliphatic side-chain with a branch. Among the proteinogenic amino acids, there are three BCAAs: leucine, isoleucine, and valine. Non-proteinogenic BCAAs include 2-aminoisobutyric acid and alloisoleucine.
Muscle weakness is a lack of muscle strength. Its causes are many and can be divided into conditions that have either true or perceived muscle weakness. True muscle weakness is a primary symptom of a variety of skeletal muscle diseases, including muscular dystrophy and inflammatory myopathy. It occurs in neuromuscular junction disorders, such as myasthenia gravis. Muscle weakness can also be caused by low levels of potassium and other electrolytes within muscle cells. It can be temporary or long-lasting. The term myasthenia is from my- from Greek μυο meaning "muscle" + -asthenia ἀσθένεια meaning "weakness".
Proteins are essential nutrients for the human body. They are one of the building blocks of body tissue and can also serve as a fuel source. As a fuel, proteins provide as much energy density as carbohydrates: 4 kcal per gram; in contrast, lipids provide 9 kcal per gram. The most important aspect and defining characteristic of protein from a nutritional standpoint is its amino acid composition.
Carnosine synthase is an enzyme that catalyzes the chemical reaction
Carnosinemia is a rare autosomal recessive metabolic disorder caused by a deficiency of carnosinase, a dipeptidase.
α-Ketoisocaproic acid (α-KIC), also known as 4-methyl-2-oxovaleric acid, and its conjugate base and carboxylate, α-ketoisocaproate, are metabolic intermediates in the metabolic pathway for L-leucine. Leucine is an essential amino acid, and its degradation is critical for many biological duties. α-KIC is produced in one of the first steps of the pathway by branched-chain amino acid aminotransferase by transferring the amine on L-leucine onto alpha ketoglutarate, and replacing that amine with a ketone. The degradation of L-leucine in the muscle to this compound allows for the production of the amino acids alanine and glutamate as well. In the liver, α-KIC can be converted to a vast number of compounds depending on the enzymes and cofactors present, including cholesterol, acetyl-CoA, isovaleryl-CoA, and other biological molecules. Isovaleryl-CoA is the main compound synthesized from ɑ-KIC. α-KIC is a key metabolite present in the urine of people with Maple syrup urine disease, along with other branched-chain amino acids. Derivatives of α-KIC have been studied in humans for their ability to improve physical performance during anaerobic exercise as a supplemental bridge between short-term and long-term exercise supplements. These studies show that α-KIC does not achieve this goal without other ergogenicsupplements present as well. α-KIC has also been observed to reduce skeletal muscle damage after eccentrically biased resistance exercises in people who do not usually perform those exercises.
N-Acetylcarnosine (NAC) is a naturally occurring compound chemically related to the dipeptide carnosine. The NAC molecular structure is identical to carnosine with the exception that it carries an additional acetyl group. The acetylation makes NAC more resistant to degradation by carnosinase, an enzyme that breaks down carnosine to its constituent amino acids, beta-alanine and histidine.
Xaa-methyl-His dipeptidase is an enzyme. This enzyme catalyses the following chemical reaction
Zinc L-carnosine, often simply called zinc carnosine, and also known as polaprezinc, is a mucosal protective chelate compound of zinc and L-carnosine invented by Hamari Chemicals, Ltd. It is a quadridentate 1:1 complex of a polymeric nature. Although it contains 23% zinc and 77% L-carnosine by mass, zinc carnosine is a molecule and not a mixture of zinc and L-carnosine.
Pre-workout is a generic term for a range of bodybuilding supplement products used by athletes and weightlifters to enhance athletic performance. Supplements are taken to increase endurance, energy, and focus during a workout. Pre-workout supplements contain a variety of ingredients such as caffeine and creatine, differing by capsule or powder products. The first pre-workout product entered the market in 1982, and since then the category has grown in use. Some pre-workout products contain ingredients linked to adverse effects. Although these products are not regulated, the Food and Drug Administration (FDA) warns consumers to be cautious when consuming them.
Glutamate decarboxylase like 1 (GADL1) is the enzyme responsible for decarboxylating aspartate (Asp) to β-alanine and cysteine sulfinic acid (CSA) to hypotaurine. GADL1 is a Pyridoxal 5’-phosphate (PLP)-dependent enzyme. By decarboxylating Asp to β-alanine, GADL1 consequently plays a role in the production of carnosine. Carnosine and taurine have multiple biological functions such as calcium regulation, pH buffering, metal chelation, and antioxidant effects. β-Alanine also plays a role as neurotransmitter or neuromodulator in the central nervous system (CNS) and olfactory bulbs.
Barbara Jean Francis Apgar is an American biochemist. She worked on important research on ribonucleic acids (RNA), and on zinc deficiency as a risk factor in reproduction. She won the Federal Woman's Award in 1970, and the Arthur S. Flemming Award in 1973.
