Nutraceuticals are changing dimension in the healthcare system of cities. A study in UK suggests that human body requires at least 45 essential nutrients and trace mineral elements for a healthy life. Severe deficiency of any one of these micro-nutrients can lead to metabolic disorders in both infants and adults.
The report further emphasizes that people that rely purely on organic diet do not receive all the trace minerals and supplements, which are essential for vital energy functions. The type and amount of mineral deficiency is related to depletion of mineral content in soil that varies from region to region or country to country.
Majority of people that live in cities and urban areas complain of fatigue and lethargy in spite of a healthy diet. Many suffer from genetic disorders or immunodeficiency diseases due to lack of essential vitamin or protein in their diet. Please refer to the table for list of genetic diseases due to deficiency of major amino acid. The study indicates that external supplementation of trace minerals, vitamins, amino-acids and proteins is clearly the key to potency and good health.
Micro-nutrition
What is micro-nutrition? Micro-nutrition is a form of nutrition that can be made easily available to body cells and tissues for vital functioning of metabolism. Micro-nutrients are small compounds, which are naturally broken-down from large molecules (macro-nutrients) during digestion and absorption process of human body (metabolism). Micro-nutrients like amino-acids can be derived synthetically from a natural source of protein that can be made ‘bio-available’ to body cells and tissues. This form of external supplementation is designed to absorb more than 98 per cent of nutrient contents in less than 20 minutes directly by body tissues.
Human genetic disorders affecting amino acid catabolism Amino-acids
Proteins are the most abundant biological macromolecules that occur in plants and animal cells. Proteins are instruments through which genetic information is expressed and display enormous diversity in biological function and structures. Proteins have distinct biological activity that act as signalling molecules in information pathways such as hormones, antibodies, enzymes.
Proteins like ketatin act as structural part of skin, eyes, spider web, nails, horns in various combinations and some proteins form structural products of muscles, collagen and ligaments. Relatively simple monomeric subunits, known as amino-acids provide the structure for thousands of different proteins.
Amino-acids are a group of 20 standard precursor molecules, which are regarded as alphabet of protein language. Amino-acids join together into product called polypeptide or simple protein. A protein molecule may have thousands of individual amino-acid residues linked together to form a single large molecule. Naturally occurring peptides range in length from two amino-acid residues to many thousands of residues.
The 20 standard amino-acids never occur in equal amount in proteins and individual proteins are assigned to family based on degree of similarity of amino-acid sequence. Members of a typical globin family (like haemoglobin, myoglobin) are identical across 25 per cent or more of their sequences. A typical family of proteins shares at least some structural and functional characteristics. Animal cells are able to specifically synthesize the l-isomer of amino-acids because the active sites of enzymes are asymmetric, which cause the reactions they catalyse to be stereo specific.
Small peptides and oligopeptides (few residues) are capable of exerting their effects at very low concentrations. For example, vertebrate hormones are small peptides such as oxytocin (nine amino-acids), bradykinin (nine residues), and thyrotropic releasing factor (three residues); Oligopeptides such as pancreatic hormone insulin (two chain of 30 residues and 21 residues), and glucagon (single chain of 29 residues). These hormones are signalling molecules involved in distinct function.
Amino-acids contained in proteins as long branched or un-branched chains contribute to many structural and functional aspect of body tissues and organs like growth and maintenance of cells, replacing old and dead tissue with new ones, regulation of carbohydrates, fats, proteins and certain enzymes, transport of nutrients and waste products throughout the body or contribute to energy secondary to carbohydrates. A number of substructures occur in many functionally unrelated proteins.
Certain amino-acid sequences serve as signals that determine the cellular location, chemical modification and half-life of protein.
Special signal sequences, usually at the amino terminus are used to target certain proteins for export from the cell, while other proteins are targeted for distribution to the nucleus. Sugar groups in glycoproteins and lipid groups in lipoproteins are attachment sites easily recognized by amino-acids.
Amino-acids are organic amino-carboxylic acids that contain one amino group (NH2), one carboxylic acid group (COOH), one hydrogen atom (H) and alkyl side chain (-R) attached to central carbon atom. They differ each other with respect to side chain group (-R group), which influence structure, size, electric charge and solubility in water.
Amino-acids classified according to the nature of side chain can be polar uncharged, polar and positively charged, polar and negatively charged, non-polar and aliphatic or non-polar and aromatic group. Amino-acids make significant contribution to generation of metabolic energy through oxidative degradation and regulation of intermediate pathways of energy. The fraction of contribution varies greatly with type of organism and metabolic conditions. It also depends upon the source of amino-acid, breakdown of dietary protein or tissue protein.
Typically, all pathways for amino-acid catabolism in human body account for 10 per cent – 15 per cent body’s energy. These pathways serve to generate intermediate metabolic precursors of sugars and fats during catabolism and anabolism. Amino-acids are finally degraded to acetyl-CoA, which is the starting product for tri carboxylic acid cycle (TCA). Five amino-acids – alanine, tryptophan, cysteine, serine and glycine are converted into pyruvate. Threonine, tryptophan, lysine, phenylalanine, leucine and isoleucine are converted in to acetyl CoA in fatty-acid metabolism.
Five amino-acids – proline, glutamate, glutamine, agrinine and histidine are converted into a-ketoglutrate; and, four amino-acids – methionine, isoleucine, valine and theorine is converted into succinyl CoA. Two amino-acids – asparagines and aspartate are degraded into oxaloacetate. Pyruvate, a-ketoglutrate or oxoglutrate, succinyl CoA and oxaloacetate are other intermediate precursors of TCA cycle that regulate catabolic and biosynthetic pathways.
Carnivores can obtain 90 per cent of their energy requirements from amino acid oxidation whereas herbivores fill only small fraction of their energy needs by this route. Micro-organisms can scavenge amino-acids from their environment and use them as fuel when required by metabolic conditions. Amino-acid metabolism is important for translation and synthesis of wide variety of important proteins, enzymes and antibodies, which is required by body for normal function.
Amino-acids converge central catabolic pathways by transforming into a-keto-acids. This type of bio-transformation provides ‘carbon skeleton’ for storing energy in different forms such as carbohydrates and fats in brain, skeletal muscle and other tissues. Most globular proteins from animal sources are almost completely hydrolyzed into amino-acids in GIT but some fibrous proteins such as keratin are only partly digested. Protein content of some plant foods is protected against breakdown by indigestible cellulose husks.
Essential amino-acids
Essential amino-acids are a group of amino-acids that cannot be produced by our body, hence, must be supplemented additionally to human body. Amino-acids derived from dietary proteins are source of most amino groups metabolized in liver. Asparagine was first found in asparagus in 1806, glutamate in wheat gluten, tyrosine isolated from cheese (Greek, Tyros, cheese) and glycine (Greek, glykos, sweet) has a sweet taste.
Degradation of amino-acids during digestion and absorption in intestine releases ammonia, which is recycled by biosynthetic pathways. Excess ammonia is either excreted directly or converted to urea to uric acid for excretion. Excess ammonia generated in extrahepatic tissues travels to the liver for conversion to the form in which it is excreted. Excess ammonia generated in other tissues is converted to amide nitrogen of glutamine in liver. Glutamate and glutamine play essential role in nitrogen metabolism.
In muscles, excess amino groups from alanine are converted to pyruvate and lactic acid for energy release. Alanine also release to nitric oxide (NO2) through cardiovascular response. It is a major cellular response or physiological effect involved in complex behavioural changes in the brain, airway relaxation, beating of the heart, dilation of blood vessels, regulation of intestinal movement, function of blood cells, and the immune system of the body – even how fingers and arms move. Amino-acids regulate human growth hormone to prevent ageing of cells. Some important functions include improvement in memory, lowering of cholesterol, stamina, vitality, potency, improvement in overall metabolism and energy.
Arginine is the most potent nutraceutical ever discovered regarded as “miracle molecule”. It is micro-nutrient supplement capable of restoring cardiovascular health by reducing cholesterol and restoring blood pressure to normal. It is used along with glutamic acid in ammonia detoxification reactions. Derivates of glutamate and glutamine are available as health supplements for treatment of chronic alcoholism, catabolic wasting process, peptic ulcers, inflammatory bowel disease and improvement of immune function of body.
Lysine is essential amino acid found in mammalian proteins. It has a long hydrocarbon chain that helps to improve utilization of vegetable proteins to act as dietary supplement. Serine, cystein and cycloserine derivatives form pharmaceutically active ingredients of many antibiotics used in treatment of tuberculosis and urinary tract infections.
Tripeptide of glycine, cysteine and glutamate called gluthoine helps in hepatoprotection (alcohol-induced liver damage), immune system support and healing of peptic ulcers. Phenylalanine derivatives are good antineoplastic agents. Branched chain amino-acids (BCAA) formed by cross-linked peptide bonds, cross-linked peptide and glycoside bonds and cross-linked peptide, glycoside and phosphate bonds help in muscle development and improvement in lean body mass.
(The author is M.D. of VMG Biotech Consultants, New Delhi)