Ana Sanches Silva

Anti-inflammatory effects of Melatonin: a mechanistic review

Abstract N-acetyl-5-methoxy-tryptamine (melatonin) is a natural substance produced both by plants, as a secondary metabolite, and animals, by the pineal gland and other tissues. In humans, melatonin participates in numerous functions including the regulation of mood, sleep, reproduction, promotion of immunomodulation, antioxidant defense and as an anti-inflammatory agent. The anti-inflammatory activity of melatonin could yield beneficial effects on intake, particularly against the chronic inflammation which underlies many chronic diseases. This review aims to provide an assessment of the literature data on the anti-inflammatory activity of melatonin, with a particular focus on the mechanisms responsible for this behavior. We can conclude that many in vitro studies and in vivo studies in experimental animal model systems show that melatonin exerts anti-inflammatory activity in a number of chronic diseases which affect different organs in different circumstances. Clinical trials, however, often fail to reach positive results and are thus far inconclusive. Thus, in the future, long-term well-designed investigations on melatonin-rich foods or melatonin food supplements could provide valuable information towards public health recommendations on melatonin, taking into account both the nature of the compound and the optimal dose, for protection from long-term inflammation linked to chronic diseases.

Regulation of autophagy by polyphenols: Paving the road for treatment of neurodegeneration

In the present paper, we will discuss on the importance of autophagy in the central nervous system, and outline the relation between autophagic pathways and the pathogenesis of neurodegenerative disorders. The potential therapeutic benefits of naturally occurring phytochemicals as pharmacological modulators of autophagy will also be addressed. Our findings provide renewed insight on the molecular modes of protection by polyphenols, which is likely to be at least in part mediated not only by their potent antioxidant and anti-inflammatory effects, but also through modulation of autophagic processes to remove the aberrant protein aggregates.