Melatonin's effects and side effects

Melatonin can have great value in the human body, because now melatonin is used in medicine to regulate skin aging, and at the same time it can regulate the body's resistance function and prevent the spread of cancer cells such as tumors. Many people usually cannot effectively control difficult and complicated diseases, so melatonin is used in medicine to slowly adjust. However, melatonin also has advantages and disadvantages. There is currently no detailed explanation of the side effects, but its efficacy is very extensive.

Main Application

N-acetyl-5-methoxytryptamine

Melatonin can improve sleep, shorten the time of awakening before bedtime and the time of falling asleep, improve sleep quality, significantly reduce the number of awakenings during sleep, shorten the light sleep stage, prolong the deep sleep stage, and lower the awakening threshold the next morning. It has a strong function of adjusting time difference. [1] It is mainly used in whitening and moisturizing cosmetics and is also commonly used in hair growth products. The biological functions of melatonin, especially its health functions as a dietary supplement, have been extensively studied at home and abroad, showing that it has many physiological functions such as promoting sleep, adjusting jet lag, anti-aging, regulating immunity, and anti-tumor. The health functions of melatonin reported at home and abroad include regulating endocrine (inhibiting ovulation), protecting against encephalitis virus infection and reducing mortality after infection, treating AIDS and protecting cardiovascular system, etc.

Delaying aging

Free radicals may be produced during enzymatic and non-enzymatic reactions in the body, and free radicals are closely related to aging. The production and elimination of free radicals in a normal body are in a dynamic balance. Once this balance is broken, free radicals will cause damage to biological macromolecules such as lipids, proteins, and nucleic acids, leading to destruction of cell structure and aging of the body. Melatonin protects cell structure, prevents DNA damage and reduces the level of peroxides in the body by scavenging free radicals, anti-oxidation and inhibiting lipid peroxidation. Research by Russel et al. found that melatonin can protect DNA from damage caused by safrole (a carcinogen that damages DNA by releasing free radicals) by up to 99%, and the effect is dose-response relationship. [2] Melatonin has a significant antagonistic effect on peroxidation caused by exogenous toxins (such as paraquat) and tissue damage caused by the free radicals produced. Melatonin can also reduce the content of LPO in the brain. Its effects on different areas of the brain, such as the cerebral cortex, cerebellum, hippocampus, hypothalamus, striatum, etc., are basically the same and are dose-dependent. However, different strains of rats, such as Sprague-Dawlay and Wistar rats, have different sensitivities to melatonin.

Fighting tumors

Vijayalaxmi et al. (1995) found in an in vitro study that melatonin has a significant protective effect on chromosomal damage in human peripheral lymphocytes caused by 137Cs gamma rays (150cGy), and the effect is dose-effect relationship; it also has an antagonistic effect on the physical and chemical mutagenicity and carcinogenicity produced by free radicals. In vitro experiments showed that melatonin also has a protective effect against the mutagenicity caused by chloramphenicol C. Melatonin can reduce the formation of DNA adducts induced by chemical carcinogens (safrole) and prevent DNA damage. Yan Jianjun et al. studied the anti-tumor effect of melatonin on H22 liver cancer mice and found that it can inhibit tumor growth and prolong the survival time of tumor-bearing mice, and has obvious synergy with IL-2. Danforth et al. measured the 24-h plasma melatonin levels of three groups of women: normal women, breast cancer women, and breast cancer-susceptible women. The results showed that normal women had a circadian rhythm; the diurnal rhythm of breast cancer patients was significantly correlated with the amount of steroid receptors in the primary tumor. The mean plasma melatonin levels from day to night in patients with estrogen (ER) or progesterone (PR) receptor-positive tumors are significantly lower than those in patients with ER or PR-negative tumors, and are significantly negatively correlated with the amount of ER or PR receptors in the primary tumor, indicating that melatonin has a certain correlation with hormone-dependent human breast cancer. Melatonin promotes the production of endogenous granulocyte/macrophage accumulation factors through bone marrow T-cells and can be used as an adjuvant therapy for tumors.

Improve sleep

Holmes studied the hypnotic effect of melatonin and its impact on neurochemistry. After rats were given 10 mg/kg BW melatonin, the EEG test showed that the time it took to fall asleep was shortened by half compared to before taking the medicine. The awakening time was also significantly shortened, and the slow-wave sleep and REM sleep were significantly prolonged and easier to wake up. Giving rats 2.5 mg/kg BW produced a similar hypnotic effect to a slightly lower degree. Melatonin at any dose did not alter the standard EEC pattern and disrupt normal sleep patterns. The hypnotic effect of melatonin 25 mg/kg BW administered intraperitoneally to mice was similar to that of cyclohexenebarbital (a hypnotic drug) 100 mg/kg BW (peritoneally).