Zinc, Inflammation, and Aging
Objective: We hypothesized that zinc down-regulates the production of atherosclerosis-related cytokines/molecules in humans.
Design: To examine these effects, we conducted a randomized, double-blinded, placebo trial of zinc supplementation in elderly subjects. We recruited 40 healthy elderly subjects (aged 56–83 y) and randomly assigned them to 2 groups. One group was given an oral dose of 45 mg zinc/d as a gluconate for 6 mo. The other group was given a placebo. Cell culture models were conducted to study the mechanism of zinc as an atheroprotective agent.
Results: After 6 mo of supplementation, the intake of zinc, compared with intake of placebo, increased the concentrations of plasma zinc and decreased the concentrations of plasma high-sensitivity C-reactive protein (hsCRP), interleukin (IL)-6, macrophage chemoattractant protein 1 (MCP-1), vascular cell adhesion molecule 1 (VCAM-1), secretory phospholipase A2, and malondialdehyde and hydroxyalkenals (MDA+HAE) in elderly subjects. Regression analysis showed that changes in concentrations of plasma zinc were inversely associated with changes in concentrations of plasma hsCRP, MCP-1, VCAM-1, and MDA+HAE after 6 mo of supplementation. In cell culture studies, we showed that zinc decreased the generation of tumor necrosis factor-, IL-1β, VCAM-1, and MDA+HAE and the activation of nuclear transcription factor B and increased antiinflammatory proteins A20 and peroxisome proliferator–activated receptor- in human monocytic leukemia THP-1 cells and human aortic endothelial cells compared with zinc-deficient cells.
Conclusion: These findings suggest that zinc may have a protective effect in atherosclerosis because of its antiinflammatory and antioxidant functions.
Bin Bao, Ananda S Prasad, Frances WJ Beck, James T Fitzgerald, Diane Snell, Ginny W Bao, Tapinder Singh, and Lavoisier J Cardozo
Zinc decreases C-reactive protein, lipid peroxidation, and inflammatory cytokines in elderly subjects: a potential implication of zinc as an atheroprotective agent
Am J Clin Nutr
Department of Internal Medicine School of Medicine Wayne State University Detroit MI