Histamine, Mast Cells Gene Controls and Body Reactions Foods, chemicals, toxins, microbes, all of these can trigger mild to severe immune responses and your SNP profile can give inside predictive clues. Personalized Genetics With the emergence of personalized genetics, many inquiries are made regarding specific genes and related SNPs in allergy and sensitivity reactions of the body when exposed to irritants and toxic agents. There are three specific genes that are involved in histamine metabolism and they all work in different ways. Namely, DAO (Diamine Oxidase), HNMT (Histamine-N-Methyltransferase) MAO-B (Monoamine Oxidase B). Diamine oxidase (DAO) decomposes histamine, especially in the intestine before uptake. Histamine-N-methyltransferase (HNMT) is able to decompose histamine inside the cells. Monoaminoxidase B (MAO-B) is able to degrade histamine and has relation to neurotransmitter function. Properties of Histamine: Histamine is a naturally occurring biogenic amine. Histamine is found in mast cells and basophils, two specialized cells actively involved in immune responses to threats of foreign invasion either microbes, pollutants, toxins, etc. Histamine is regulating many metabolic processes. Its most important function is probably to alert the body in case of microbial attacks. Signaling Pathway: Histamine activates four different known histamine receptors (H1, H2, H3, H4) located on the surface of the cells. They are transmitting the chemical signal into the cell. Furthermore, histamine can also enter the cell by active transmembranal transport mechanisms. Signal proteins can be activated by monoaminylation, which causes long term hormonal reactions, but is still poorly understood. H1-receptors are transmitting the most important effects of histamine: Allergy-like symptoms like itching and pain, inflammation, muscle contraction in bronchi and large blood vessels and enlargement of small blood vessels, blood pressure, regulation of body temperature. H2-receptors are enhancing the production of gastric acid, they are accelerating the intestinal motility (diarrhea) and the heartbeat. H3-receptors are inhibiting further release of histamine. Release of other mediators is regulated. H4-receptors are directing immune cells towards the source of histamine, into inflammation hotspots. To be continued.........
Posted on: Sun, 21 Sep 2014 19:35:32 +0000