Resveratrol, tryptophanum, glycine and vitamin E : a nutraceutical approach to sleep disturbance and irritability in peri- and post-menopause

The climacteric syndrome is characterized by several symptoms: hot flashes are the most common and reported by about 70% of peri- post-menopausal women. Sleep disorders, particularly decreased sleep quality, and irritability are also commonly reported. There is a clinical and epidemiological relationship between these symptoms. Common biological mechanisms may explain in part the relationship between hot flushes, sleep disorders and irritability. For example, withdrawal of hormones causes change in the serotonin levels. Tryptophan is an essential amino acid. it is the precursor for the serotonin synthesis and is naturally found in food such as turkey, cheese, and nuts. The serotonergic system is implicated in sleep, mood, and hot flashes. Glycine is an amino acid found mainly in protein-rich food such as meat, fish, dairy products, cheese and vegetables. It is an inhibitory neurotransmitter in the central nervous system. Studies have shown that glycine can promote a deeper level of sleep. Resveratrol has a similar chemical structure to the diethylstilbestrol and 17-beta estradiol and acts as a phytoestrogen. Resveratrol at doses of 3-10 micromoles inhibited the estradiol-estrogen receptor binding and showed an estrogen-like activity. Vitamin E is found naturally in some food and available as a dietary supplement. It has an antioxidant activity. It has been suggested that the oxidative stress may also play a role in sleep disorders. Some studies have shown protective effect of vitamins E on sleep quality. In conclusion, hot flashes, sleep disturbances and mood disorders may represent a continuum in the climacteric syndrome, which recognize in the hormonal changes and the neurotrasmettitors level alteration a potential common pathway. The nutraceutical approach may be useful in a preventive perspective. Among the large choice of functional food available, the combination of resveratrol, tryptophanum, glycine and vitamin E may represent an interesting opportunity in the routine clinical practice.