Vitamin B2 measurement is used to investigate hypovitaminosis and to monitor supplement therapy.
Vitamin B2 (riboflavin) is a water-soluble vitamin. It is composed of plants and microorganisms and naturally occurs in three forms: the physiologically inactive riboflavin; the physiologically active coenzymes flavin mononucleotide (FMN); and flavin adenine dinucleotide (FAD). FAD accounts for about 90% of total riboflavin in the blood. Due to their ability to carry electrons, FAD and FMN are essential for the transport of protons in the respiratory chain, for the dehydration of fatty acids, the oxidative deamination of amino acids, and for other redox processes.
Nutrition-derived flavin derivatives (FAD, FMN) are separated in the stomach by gastric acid from their binding proteins, transformed with riboflavin by enzymes (phosphatases), and absorbed into the small intestine. The (re)conversion of riboflavin to FMN and FAD coenzymes occurs in the cytoplasm of cells in many different tissues (liver, kidney, small intestine, heart). Very little riboflavin is stored in the small intestine and excreted in the urine. Riboflavin deficiency occurs almost always in combination with deficiency of other B-complex vitamins (nicotinamide, folic acid, and pantothenic acid).
Symptoms of riboflavin deficiency appear mainly as pathological changes in the skin and mucous membranes (cuts on the tongue and corner of the mouth, itching, seborrheic dermatitis, inflammation in the skin of the perineal area), corneal lesions, thrombosis, and atherosclerosis. These symptoms are a consequence of the accumulation of lipid peroxides. As a causative factor of this peroxidation besides oxidative stress, it is also the most oxidizing amino acid, homocysteine. Vitamin B2 deficiency results in decreased activity of flavin-containing enzymes (glutathione reductase and glutathione peroxidase), which in turn allows these peroxides to express their deleterious effects. Severe riboflavin deficiency can affect the conversion of vitamin B6 to its coenzyme as well as the conversion of tryptophan to niacin.
Riboflavin has a low level of toxicity and has never been reported, any case of toxicity. Its limited absorption in the intestine, combined with its easy excretion in the urine, precludes any problems associated with increased riboflavin intake.
Important Note
Laboratory test results are the most important parameter for the diagnosis and monitoring of all pathological conditions. 70%-80% of diagnostic decisions are based on laboratory tests. The correct interpretation of laboratory results allows a doctor to distinguish "healthy" from "diseased".
Laboratory test results should not be interpreted from the numerical result of a single analysis. Test results should be interpreted in relation to each individual case and family history, clinical findings, and the results of other laboratory tests and information. Your personal physician should explain the importance of your test results.
At Diagnostiki Athinon we answer any questions you may have about the test you perform in our laboratory and we contact your doctor to get the best possible medical care.
