MEZVITE

In its biologically active form vitamin D₃ stimulates intestinal calcium absorption, incorporation of calcium into the osteoid, and release of calcium from bone tissue. In the small intestine it promotes rapid and delayed calcium uptake. The passive and active transport of phosphate is also stimulated.

Vitamin E is known to exert an important physiological function as an antioxidant for fats, with a sparing action on vitamin A, carotenoids and on unsaturated fatty acids. Other work has demonstrated that vitamin E is connected with the maintenance of certain factors essential for the normal metabolic cycle.

Ascorbic acid, coupled with dehydroascorbic acid to which it is reversibly oxidised, has a variety of functions in cellular oxidation processes. Ascorbic acid is required in several important hydroxylations, including the conversion of proline to hydroxyproline and appears to have an important role in metal ion metabolism, including the gastrointestinal absorption of iron and its transport between plasma and storage organs.

Thiamine pyrophosphate (TPP), the coenzymatic form of thiamine, is involved in two main types of metabolic reactions: decarboxylation of α-ketoacids (e.g. pyruvate, α-ketoglutarate and branched-chain keto acids) and transketolation (e.g. among hexose and pentose phosphates). Therefore, the principal physiological role of thiamine is as a coenzyme in carbohydrate metabolism, where TPP is required for several stages in the breakdown of glucose to provide energy.

Riboflavine is phosphorylated to flavine mononucleotide and flavine adenine dinucleotide which act as co-enzymes in the respiratory chain and in oxidative phosphorylation. Riboflavine deficiency presents with ocular symptoms, as well as lesions on the lips and at angles of the mouth.

Niacin (nicotinic acid) is an essential B complex Vitamin (B₃), whose deficiency results in the clinical syndrome known as pellagra. Nicotinamide (niacinamide), the active ingredient, is the physiologically active form of niacin and is the chemical form of Vitamin B₃ found in virtually all multivitamin products. Though nicotinic acid and nicotinamide are so closely related chemically, they differ somewhat in pharmacological properties.

Pyridoxine hydrochloride is Vitamin B6. It is converted to pyridoxal phosphate which is the co-enzyme for a variety of metabolic transformations. It is essential for human nutrition.

Folic acid is a member of the vitamin B group which is reduced in the body to tetrahydrofolate, a co-enzyme active in several metabolic processes and produces a haemopoietic response in nutritional megaloblastic anaemias. Folic acid is rapidly absorbed and widely distributed in body tissues.

Hydroxocobalamin is used in the treatment and prevention of Vitamin B12 deficiency. For adults, the daily requirement of Vitamin B12 is probably about 1 to 2 micrograms and this amount is present in most normal diets. However, Vitamin B12 only occurs in animal products, not in vegetables, and therefore strict vegetarian or vegan diets that exclude dairy products may provide an inadequate amount, although a deficiency may not be apparent for many years.

Biotin is a co-enzyme for carboxylation during the metabolism of proteins and carbohydrates.

Pantothenic acid is incorporated into co-enzyme A and is involved in metabolic pathways involving acetylation which includes detoxification of drug molecules and biosynthesis of cholesterol, steroid hormones, mucopolysaccharides and acetylcholine. CoA has an essential function in lipid metabolism.

Zinc blocks the intestinal absorption of copper from the diet and the reabsorption of endogenously secreted copper. Zinc induces the production of metallothionein in the enterocyte, a protein that binds copper thereby preventing its transfer into the blood. The bound copper is then eliminated in the stool following desquamation of the intestinal cells.

Copper is a mineral that is found throughout the body. Copper helps the body absorb iron. It is also important for nerve function, bone growth, and to help your body use sugar. It also helps form collagen, a key part of bones and connective tissue. Copper may also act as an antioxidant, reducing free radicals that can damage cells and DNA.

Manganese is required for the synthesis of the mucopolysaccharides of cartilage, glucose utilisation, steroid biosynthesis and for the activity of pyruvate carboxylase. It is bound to arginase of the liver and activates many enzymes.

Iodine is an essential trace element in the human diet, necessary for the formation of thyroid hormones and consequently it is used in iodine deficiency and thyroid disorders. It also has antimicrobial activity.

For the prophylaxis and treatment of iodine deficiency disorders it may be given as potassium or sodium iodide, iodised oil, or potassium iodate. In the pre-operative management of hyperthyroidism iodine and iodides are used with antithyroid drugs such as carbimazole, thiamazole, or propylthiouracil.

Iodine has a powerful bactericidal action. It is also active against fungi, viruses, protozoa, cysts, and spores. Iodine is used as an antiseptic and disinfectant generally as a 2% or 2.5% solution.