How does a living organism repair and protect itself from the wear and tear of life? This is done via a whole number of protective molecules. One of those molecular groups are widely prsent in nature, in plants, in simple evertebrates, in vertebrates and in man. These are the familiy of molecules we call the N-acylethanolamines (NAEs). PEA is such a molecule.
PEA and related NAEs are endogenous molecules involved in cellular protectve mechanisms that are activated in the body as a result of tissue damage or stimulation or inflammatotion and after stimpulation of nociceptive fibres.
The N-acylethanolamines consists of a whole familya of naturally occurring lipidic mediator molecules composed of a fatty acid and ethanolamine.
It is widely known now that PEA and other NAEs are produced in our cells and that these molecules excerts protective, anti-inflammatory and analgesic actions. Less is known that NAEs are also present in plants and fungi, suggesting that a protective and signaling pathway exist, similar to the mammalian system. It also points out how important this protective system is in nature, as we can find it in all living organisms, apart from insects.
Other, with PEA related signaling NAEs, such as anandamide and 2-AG are also found all over the place, for instance in invertebrates, such as molluscs, coelanterata such as the Hydra and little worms, such as Caenorhabditis elegans, which all do not express CB1 or CB2 receptors.
Plant NAE were first identified in processed, seed-derived products at concentrations several fold higher than typically found in the leaves. The NAE types identified in seeds are composed of 12–18 carbon atoms with zero to three double bonds. PEA has 18 carbon atoms with zero double bomds.
The major types of NAE identified in seeds are similar to those that occur in animal tissues.
For instance, in legume seeds, NAE profiles were similar to those in non-leguminous seeds, with concentrations ranging from 0.17 microg/g in the common bean to 44.6 microg/g in Medicago truncatula on a fresh weight basis.
Because of the elevated concentrations of NAE in seeds, plants could also provide a rich source of these compounds for therapeutic applications for modulating the pain and inflammation in mammals. It is also clear why PEA is classified as food for medical purposes or a food supplement.
Research during the past decade has shown that NAE such as PEA impact a great number of important biological processes in plants (and animals) indicating that these compounds most probably also play fundamental roles in plants.
NAEs can have different functions in plants, such as delaying flower senescence, and inhibiting lipid peroxidation and ion leakage. One of the first indications that NAE could be significant for plant function was the observation that these compounds accumulated in the growth media of plant cells and in leaves very quickly after applying a for the plant toxic compound ( a mould). NAE accumulation in plants probably functions to fend off bacteria and moulds, and play analogous roles to the cryoprotective activity attributed to NAE in animal tissues subjected to toxics, oxygen shortage and cellular stress like tissue damage and ischemia.
One mechanism by which NAE in plants facilitate defense and protection could be through the induction of so called defense related genes.
Lesion-induced increases of MAEs such as anandamide and PEA levels occur in the early stage of stress, with an upregulation of the synthesizing enzymes (NAPE-PLD) and via a downregulation of the PEA- and anandamide-degradative enzymes.