Biogenic amine

A biogenic amine is a biogenic substance with one or more amine groups. They are basic nitrogenous compounds formed mainly by decarboxylation of amino acids or by amination and transamination of aldehydes and ketones. Biogenic amines are organic bases with low molecular weight and are synthesized by microbial, vegetable and animal metabolisms. In food and beverages they are formed by the enzymes of raw material or are generated by microbial decarboxylation of amino acids.^[1]

Importance in food

Biogenic amines can be found in all foods containing proteins or free amino acids and are found in a wide range of food products including fish products, meat products, dairy products, wine, beer, vegetables, fruits, nuts and chocolate. In non-fermented foods the presence of biogenic amines is mostly undesired and can be used as indication for microbial spoilage. In fermented foods, one can expect the presence of many kinds of microorganisms, some of them being capable of producing biogenic amines.

They play an important role as source of nitrogen and precursor for the synthesis of hormones, alkaloids, nucleic acids, proteins, amines and food aroma components. However, food containing high amounts of biogenic amines may have toxicological effects.^[1]

Examples

Some prominent examples of biogenic amines include:

Classical monoamines

• Histamine - a substance derived from the amino acid histidine that acts as a neurotransmitter mediating arousal and attention, as well as a pro-inflammatory signal released from mast cells in response to allergic reactions or tissue damage. Histamine is also an important stimulant of HCl secretion by the stomach through histamine H₂ receptors.
• Serotonin - a central nervous system neurotransmitter derived from the amino acid tryptophan involved in regulating mood, sleep, appetite, and sexuality.
• The three catecholamine neurotransmitters:
  • Norepinephrine (noradrenaline) - a neurotransmitter involved in sleep and wakefulness, attention, and feeding behavior, as well as a stress hormone released by the adrenal glands that regulates the sympathetic nervous system.
  • Epinephrine (adrenaline) - an adrenal stress hormone, as well as a neurotransmitter present at lower levels in the brain.
  • Dopamine - a neurotransmitter involved in motivation, reward, addiction, behavioral reinforcement, and coordination of bodily movement.

The trace amines

• Phenethylamines (related to catecholamines):
  • Phenethylamine^[2][3] (PEA)
  • N-Methylphenethylamine^[4][2] (endogenous amphetamine isomer)
  • Phenylethanolamine^[5]
  • m-Tyramine^[2]
  • p-Tyramine^[2]
  • N-Methyltyramine^[4][2]
  • m-Octopamine^[2]
  • p-Octopamine^[2]
  • Synephrine^[4]
  • 3-Methoxytyramine^[4]
• Thyronamine compounds:
  • 3-Iodothyronamine^[3]
• Tryptamine^[4][3]

Physiological importance

There is a distinction between endogenous and exogenous biogenic amines. Endogenous amines are produced in many different tissues (for example: adrenaline in adrenal medulla or histamine in mast cells and liver). The amines are transmitted locally or via the blood system. The exogenous amines are directly absorbed from food in the intestine. Alcohol can increase the absorption rate. Monoamine oxidase (MAO) breaks down biogenic amines and prevents excessive resorption. MAO inhibitors (MAOIs) are also used as medications for the treatment of depression to prevent MAO from breaking down amines important for positive mood.

See also

• Monoamine neurotransmitter
• Trace amine

References

1. Santos, M.H.Silla. "Biogenic amines: their importance in foods". International Journal of Food Microbiology 29 (2-3): 213–231. doi:10.1016/0168-1605(95)00032-1.
2. Broadley KJ (March 2010). "The vascular effects of trace amines and amphetamines". Pharmacol. Ther. 125 (3): 363–375. doi:10.1016/j.pharmthera.2009.11.005. PMID 19948186. Trace amines are metabolized in the mammalian body via monoamine oxidase (MAO; EC 1.4.3.4) (Berry, 2004) (Fig. 2) ... It deaminates primary and secondary amines that are free in the neuronal cytoplasm but not those bound in storage vesicles of the sympathetic neurone ... Similarly, β-PEA would not be deaminated in the gut as it is a selective substrate for MAO-B which is not found in the gut ...
   Brain levels of endogenous trace amines are several hundred-fold below those for the classical neurotransmitters noradrenaline, dopamine and serotonin but their rates of synthesis are equivalent to those of noradrenaline and dopamine and they have a very rapid turnover rate (Berry, 2004). Endogenous extracellular tissue levels of trace amines measured in the brain are in the low nanomolar range. These low concentrations arise because of their very short half-life ...
3. Miller GM (January 2011). "The emerging role of trace amine-associated receptor 1 in the functional regulation of monoamine transporters and dopaminergic activity". J. Neurochem. 116 (2): 164–176. doi:10.1111/j.1471-4159.2010.07109.x. PMC 3005101. PMID 21073468.
4. Lindemann L, Hoener MC (May 2005). "A renaissance in trace amines inspired by a novel GPCR family". Trends Pharmacol. Sci. 26 (5): 274–281. doi:10.1016/j.tips.2005.03.007. PMID 15860375. In addition to the main metabolic pathway, TAs can also be converted by nonspecific N-methyltransferase (NMT) [22] and phenylethanolamine N-methyltransferase (PNMT) [23] to the corresponding secondary amines (e.g. synephrine [14], N-methylphenylethylamine and N-methyltyramine [15]), which display similar activities on TAAR1 (TA1) as their primary amine precursors...Both dopamine and 3-methoxytyramine, which do not undergo further N-methylation, are partial agonists of TAAR1 (TA1). ...
   The dysregulation of TA levels has been linked to several diseases, which highlights the corresponding members of the TAAR family as potential targets for drug development. In this article, we focus on the relevance of TAs and their receptors to nervous system-related disorders, namely schizophrenia and depression; however, TAs have also been linked to other diseases such as migraine, attention deficit hyperactivity disorder, substance abuse and eating disorders [7,8,36]. Clinical studies report increased β-PEA plasma levels in patients suffering from acute schizophrenia [37] and elevated urinary excretion of β-PEA in paranoid schizophrenics [38], which supports a role of TAs in schizophrenia. As a result of these studies, β-PEA has been referred to as the body’s ‘endogenous amphetamine’ [39]
5. Wainscott DB, Little SP, Yin T, Tu Y, Rocco VP, He JX, Nelson DL (January 2007). "Pharmacologic characterization of the cloned human trace amine-associated receptor1 (TAAR1) and evidence for species differences with the rat TAAR1". The Journal of Pharmacology and Experimental Therapeutics 320 (1): 475–85. doi:10.1124/jpet.106.112532. PMID 17038507.

External links

• The Biogenic Amines - Neuroscience 2nd edition, Dale Purves et al.