Disorders of innate immunity in human ageing and effects of nutraceutical administration

Immune decline with ageing accounts for the increased risk of infections, inflammatory chronic disease, autoimmunity and cancer in humans. Both innate and adaptive immune functions are compromised in aged people and, therefore, attempts to correct these dysfunctions represent a major goal of modern medicine. In this review, special emphasis will be placed on the aged innate immunity with special reference to polymorphonuclear cell, monocyte/ macrophage, dendritic cell and natural killer cell functions. As potential modifiers of the impaired innate immunity, some principal nutraceuticals will be illustrated, such as micronutrients, pre-probiotics and polyphenols. In elderly, clinical trials with the above products are scanty, however, some encouraging effects on the recovery of innate immune cells have been reported. In addition, our own results obtained with symbiotics and polyphenols extracted from red wine or fermented grape marc suggest the potential ability of these substances to modulate the innate immune response in ageing, thus reducing the inflammaging which characterizes immune senescence.