Does melatonin work
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The Efficacy of Melatonin: A Comprehensive Review
Melatonin and Neuroprotection
Melatonin, an endogenous hormone, has demonstrated significant neuroprotective properties. Research indicates that melatonin can mitigate the adverse effects of 5-fluorouracil (5-FU) on hippocampal neurogenesis and antioxidant activity in rats. Specifically, melatonin was found to reduce oxidative stress and restore antioxidant enzyme levels in the hippocampus and prefrontal cortex, which are critical for working memory. This suggests that melatonin can counteract the neurotoxic effects of 5-FU, highlighting its potential as a neuroprotective agent1.
Melatonin in Sleep Disorders
Melatonin is widely recognized for its role in regulating sleep-wake cycles. A meta-analysis of randomized, controlled studies has shown that exogenous melatonin is effective in reducing sleep onset latency in individuals with primary insomnia, delayed sleep phase syndrome, and non-24-hour sleep-wake syndrome in blind patients. These findings underscore melatonin's potential in treating various primary sleep disorders, although further large-scale trials are recommended to solidify these results2.
Antioxidant and Anti-inflammatory Properties
Melatonin is a potent antioxidant and free radical scavenger, surpassing even vitamin E in its efficacy. It upregulates antioxidant enzymes and has significant anti-inflammatory properties. These attributes make melatonin a valuable therapeutic agent against oxidative stress-related conditions, including neurodegenerative diseases, cardiovascular diseases, and immune disorders3 9.
Melatonin in Cancer Treatment
Melatonin has shown promise as an anti-cancer agent, particularly in liver cancer. It inhibits cancer cell proliferation, motility, and invasiveness, and induces apoptosis in hepatocellular carcinoma (HCC) cells. Melatonin's ability to modulate oxidative stress, immune response, and various signaling pathways makes it a potential adjunct in cancer therapy. Combining melatonin with chemotherapy could enhance its anti-cancer effects4 6.
Melatonin and Circadian Rhythm Regulation
Melatonin plays a crucial role in maintaining circadian rhythms, which are essential for overall health. It helps synchronize the body's internal clock with the external environment, thereby optimizing various physiological functions. This is particularly important for individuals working night shifts, although studies have shown mixed results regarding melatonin's effectiveness in improving sleep quality and mood in such populations5 10.
Melatonin in Pregnancy
Melatonin is vital for maternal and fetal health during pregnancy. It crosses the placenta and provides photoperiodic information to the fetus, aiding in the regulation of circadian rhythms. Melatonin's antioxidant and cytoprotective properties help mitigate complications such as pre-eclampsia and fetal brain damage. Maintaining stable circadian rhythms during pregnancy is crucial for fetal development and maternal health8 10.
Conclusion
Melatonin is a versatile hormone with a wide range of therapeutic applications. Its neuroprotective, antioxidant, and anti-inflammatory properties make it a valuable agent in treating sleep disorders, cancer, and oxidative stress-related conditions. While further research is needed to fully understand its potential, current evidence supports the efficacy of melatonin in various clinical settings.
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Most relevant research papers on this topic
Melatonin Protects against the Side-Effects of 5-Fluorouracil on Hippocampal Neurogenesis and Ameliorates Antioxidant Activity in an Adult Rat Hippocampus and Prefrontal Cortex
Melatonin protects against 5-fluorouracil-induced neurogenesis and oxidative stress in the hippocampus and prefrontal cortex, restoring antioxidant enzyme levels and reducing oxidative stress.
RCT
Animal Study
Rigorous JournalEvidence for the efficacy of melatonin in the treatment of primary adult sleep disorders.
Exogenous melatonin shows promising evidence in reducing sleep onset latency in primary insomnia, delayed sleep phase syndrome, and regulating sleep-wake patterns in blind patients compared to placebo.
Meta-Analysis
Highly CitedMelatonin: Nature's most versatile biological signal?
Melatonin plays a crucial role in regulating various body functions, including timekeeping, antioxidant properties, and immune-enhancing effects, and has potential therapeutic applications for various sleep disorders.
Highly CitedHuman hepatocellular carcinoma: Protection by melatonin
Melatonin effectively combats human hepatocellular carcinoma by inducing apoptosis, inhibiting cancer cell proliferation, motility, and invasiveness, and reducing oxidative stress, potentially combining with chemotherapy for cumulative effects.
Systematic ReviewCan melatonin improve adaptation to night shift?
Melatonin does not show significant clinical benefits in improving sleep quality, mood, or workload ratings for EMS personnel working rotating night shifts.
RCTHighly CitedMelatonin as an Antitumor Agent against Liver Cancer: An Updated Systematic Review
Melatonin shows potential as an antitumor agent against liver cancers, preventing carcinogenesis and offering a promising treatment option for hepatocellular carcinoma and cholangiocarcinoma.
Systematic ReviewRigorous JournalEffects of melatonin on oxidative stress, and resistance to bacterial, parasitic, and viral infections: a review.
Melatonin has antioxidant, immunomodulatory, and neuroprotective effects, making it a potential therapeutic alternative against bacterial, parasitic, and viral infections.
Highly CitedMelatonin and pregnancy in the human.
Melatonin plays a crucial role in human pregnancy, regulating biological rhythms, endocrine modulation, and preventing complications like abortion, pre-eclampsia, and fetal brain damage.
Systematic ReviewHighly CitedIs Melatonin the Cornucopia of the 21st Century?
Melatonin supplementation shows potential in treating oxidative stress- and inflammation-related disorders, with potential benefits for obesity, cardiovascular diseases, immune disorders, cancer, neurodegenerative diseases, osteoporosis, and infertility.
Rigorous JournalHighly CitedMelatonin and stable circadian rhythms optimize maternal, placental and fetal physiology.
Melatonin and stable circadian rhythms play crucial roles in maintaining maternal, placental, and fetal health during pregnancy, with regular light/dark cycles and melatonin supplementation promoting optimal fetal development.
Systematic ReviewHighly Cited