Immune regulation by plant melatonin: a review

The basic structure of melatonin is evolutionarily conserved. Hence, it was speculated that melatonin may be present in different animals (from unicellular to multi-cellular) and even in plants. Melatonin in plans is generally regarded as phyto-melatonin. Like the role of melatonin in animals, phyto-melatonin can perform a number of functions like attenuation of apoptosis, prevention of free radical generation, protection against UV irradiation etc. But, unlike phyto-estrogen, the role of phyto-melatonin in animals is totally an unexplored area. Hence, aim of the present study was to note the role of phyto-melatonin in maintenance of general health and immunity of goats. To fulfil the aim, we supplemented the goats with phyto-melatonin rich diet i.e. corn (Zea mays) which is having 1.4 ng/gm of dry weight of tissue and they are also edible to goats. We noted significantly high level of body weight, haematological (AST, ALT level, total RBC count and %Hb), immunological (TLC, %LC, %SR of PBMCs), metabolic (plasma glucose, cholesterol, HDL, LDL, protein levels and HDL: LDL ration), free radical (SOD, catalase, GPx levels), hormonal (estrogen, melatonin), cytokine (IL-6 and TNF-α) levels and significantly low level of MDA. However, plasma testosterone was unaffected upon phyto-melatonin treatment. Thus, for the first time role of phyto-melatonin as a protective molecule with improving effect on the health and immunity of Indian goat Capra hircusis being proposed, as the effect of phyto-melatonin supplementation can be brought back to normal and this dietary supplement might be utilizing the similar pathway as commercial melatonin. There are so many less expensive and readily available sources of phyto-melatonin that requires the proper knowledge of exploitation of these sources for extreme benefit for animals as well as for the human beings in near or far future.