Neurotrophins' Modulation by Olive Polyphenols

Background: Polyphenols are probably the most known and investigated molecules of nutritional interest as micronutrients present in abundance in our diet. Some of the most important food sources of polyphenols in the Mediterranean diet are olives and olive oil. A growing body of evidence from animal models to clinical studies indicates that polyphenol compounds may have neuroprotective effects in several pathologies of the nervous system through the control of oxidative stress, inflammation, apoptosis and mitochondrial dysfunction. Objective: Based on the most recent scientific literature, dietary intake of polyphenols attenuates oxidative stress and reduces risk for related neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, stroke, multiple sclerosis and Huntington's disease. Also at the peripheral level, they act as antioxidant, defending tissues against oxidative damage and scavenging free radicals. Results: Recent findings in animal models and humans show that polyphenols may have a role in regulating neurotrophins levels, in particular nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), suggesting that polyphenols may also induce their protective effects through the potentiation of neurotrophins action. NGF and BDNF, primarily known as biological mediators stimulating neuron growth, proliferation, survival and differentiation are recently studied also as metabotrophic factors, acting on glucose and energy metabolism, pancreatic beta cells and cardiovascular homeostasis. Conclusion: In this context, a better understanding of the effects of polyphenols on neurotrophins and their receptors (TrkA, TrkB, p75(NTR)) could certainly generate interest for drug discovery and also for the potential dietary prevention of several neurological and cardiometabolic diseases.