Vitamin B12 (Hydroxocobalamin)

Vitamin B12 is normally involved in several metabolisms such as DNA synthesis and regulation, fatty acid synthesis, and energy production. Vitamin B12 had been usually treated as sport nutrition, and used to prevent elderly people from getting anaemic in past years. Vitamin B12 was regarded as painkilling vitamin in some countries from 1950. Recently studies have shown that vitamin B12 played a key role in the normal functioning of the brain and nervous system and the formation of blood. Vitamin B12 has some analogues including cyanocobalamin (CNCbl), methylcobalamin (MeCbl), hydroxocobalamin (OHCbl), and adenosylcobalamin (AdoCbl). Co-methylcobalmin is a coenzyme of methionine synthase, which is required for the formation of methionine from homocysteine in the methylation cycle which involves methylation of DNA or proteins. Compared with other analogues, Co-methylcobalamin is the most absorbable by subcellular organelles of neurons. Therefore, it may provide better treatments for nervous disorders through effective systemic or local delivery (1). Vitamin B12 is essential for healthy blood. When the body does not have enough B12, it leads to decreased normal red blood cell production (anemia), which impairs oxygen delivery. Megaloblastic anemia, also called nutritional-deficiency anemia, is a type of anemia caused by B12 or folate deficiency. Megaloblastic anemia is characterized by impaired DNA synthesis and the formation of large, abnormal, immature red blood cells. In normal pregnancy, B12 levels fall by 30% by the third trimester of pregnancy (2). As B12 plays as important role in new tissue development, deficiency can be associated with infertility and repeated miscarriage (3). Untreated B12 has been associated with adverse neurological outcomes in exclusively breastfed infants (4).