Melatonin immune effects

Potentized homeopathic medicines have preferential action on sides of the body some are more effective on one side than on the other. This differential effect of the medicines with respect to laterality can be traced to functional asymmetry of the human brain. The brain can asymmetrically modulate nurochemical, neuroendocrine and immune reactivity. Potentized drugs are very often selected on the basis of time modalities of symptoms of a disease. The time modalities of the drug action can be correlated with the internal clock or biological rhythms of organisms which are disturbed in diseased conditions. Melatonin, secreted in the brain, has marked influence on the circadian rhythms. 

Over the next few decades, researchers learned that melatonin had many other effects in addition to influencing pigmentation in amphibians. Most current research has studied its influence on promoting sleep. Other studies have linked this hormone to other processes such as reducing jet lag, boosting the immune system, and fighting cancer. 

Melatonin has been shown to boost certain parts of the immune system. It boosts the activity of natural killer cells, a type of immune cell. It also prevents apoptosis, a type of destruction of T-lymphocytes, which are other important immune cells found in the bloodstream. Melatonin also limits the effect of corticosteroids on the immune system Corticosteroids are very potent drugs that are sometimes used to inhibit the immune system. Some people have autoimmune diseases in which their immune system attacks the cells of their own bodies. Physicians frequently prescribe corticosteroids for these individuals. 

Rogers N, van den Heuvel C, Dawson D. Effect of melatonin and corticosteroid on in vitro cellular immune function in humans. J Pineal Res 1997 22 75-80. 

SAR studies on melatonin analogues showed that methoxy and amido moieties are important for binding to melatonin receptors various substituents on the 2nd position of the indole ring enhance the binding affinity [52-54]. The conformational flexibility of the C-3 ethylamido side chain is probably responsible for the broad spectrum of biological activities. As a powerful antioxidant melatonin was shown to have significantly broader actions including oncostatic effects [55], immune system stimulation [56], and antiinflammatory functions [57,58]. 

Melatonin has side effects, but much less so than pharmaceutical sleeping pills. Long-term safety is not known. Prolonged use may have an influence on sex organs and reduce libido. It may slightly lower blood pressure. People with the symptoms of severe mental illness, severe allergies, autoimmune diseases, or immune system cancers such as leukemia should not... 

Esteban S, Nicolaus C, Garmundi A, Rial RV, Rodriguez AB, Ortega E, Ibars CB. Effect of orally administered L-tryptophan on serotonin, melatonin, and the innate immune response in the rat. Mol Cell Biochem 2004 267 39-46. 

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