In vitro Effects of Polyphenols on the Peripheral Immune Responses in Nickel-sensitized Patients

Nickel (Ni) is a metal largely present in the environment and prolonged exposure to it may lead to multiple pathological conditions in human subjects. Among these, the most frequent is allergic contact dermatitis.Peripheral blood mononuclear cells isolated from 25 patients with Ni-dependent contact dermatitis were evaluated in terms of cytokine release and nitric oxide (NO) production in the presence or absence of two doses (3 and 5 µg, respectively) of polyphenols.Polyphenols were able to reduce the increased release of interferon-γ and interleukin (IL)-4, while maintaining the equilibrium between IL-10 and IL-17. At the same time, exaggerated release of NO was reduced by polyphenol supplementation.In view of their anti-inflammatory activities, polyphenols may represent a potential therapeutic tool to treat Ni-sensitized patients.