Zinc Supplementation Improves Anticancer Activity of Monocytes in Type-2 Diabetic Patients with Metabolic Syndrome

BACKGROUND: Transmembrane tumor necrosis factor (TNF)-α, found on monocytes, is a body's key defense against cancer. In patients with type 2 diabetes mellitus (DM) and metabolic syndrome, immunity is suppressed, resulting in a high risk of several inflammatory disorders and cancer. PATIENTS AND METHODS: Seventeen patients with type 2 DM and metabolic syndrome were supplemented with either 30 mg of elemental zinc/day or placebo for eight weeks. Transmembrane TNF-α-expressing monocytes and lymphocytes, and plasma TNF-α levels were analyzed before and after supplementation. RESULTS: The present study revealed that zinc supplementation significantly increased the proportion of monocytes expressing transmembrane TNF-α. While the plasma TNF-α levels and TNF-α expressing lymphocytes were not significantly altered in the zinc-treated and placebo groups, higher proportion of TNF-α bound monocytes were observed in the zinc-treated group. CONCLUSION: Because functional transmembrane TNF-α was shown to be implicated in defense mechanisms, these findings suggest that zinc supplementation may benefit immune response against cancer in patients with DM and metabolic syndrome.