Oxidative stress and inflammatory markers in relation to circulating levels of adiponectin

Previous epidemiological studies together with animal studies have suggested an association between adiponectin and oxidative stress and inflammation, but community-based studies are lacking. Our objective was to investigate the relative importance of oxidative stress and inflammatory markers, representing different pathways in relation to adiponectin.

In a cross-sectional sample of 929 70-year-old individuals (50% women) of the Prospective Investigation of the Vasculature in Uppsala Seniors study, relations between serum adiponectin and oxidative stress [conjugated dienes (CD), homocysteine, total antioxidant capacity, oxidized low-density lipoprotein (OxLDL), OxLDL antibodies, baseline CD of LDL, glutathione (GSH), total glutathione (TGSH), glutathione disulfide], circulation interleukins (IL-6, IL-8), other cytokines [tumor necrosis factor α, monocyte chemotactic protein-1 (MCP-1), epidermal growth factor (EGF), vascular endothelial growth factor], cell adhesion molecules (vascular cell adhesion molecule-1, intercellular adhesion molecule-1, E-selectin, P-selectin, L-selectin), and systemic inflammatory markers [C-reactive protein (CRP), leukocyte count] in separate models were investigated.

In age- and sex-adjusted, as well as multivariable-adjusted models, adiponectin was significantly and positively associated with GSH, log TGSH, whereas an inverse association was observed for CD and log EGF. An inverse association between adiponectin and MCP-1, log E-selectin, and log CRP was significant in age- and sex-adjusted models, but not in multivariable-adjusted models.

Our results imply that higher levels of adiponectin are associated with a more beneficial oxidative stress profile, with higher levels of principal anti-oxidative GSH and total GSH together with lower levels of lipid peroxidation, possibly through shared pathways. Further studies are needed to investigate whether changes in the oxidative stress profile may be a mechanism linking adiponectin with type 2 diabetes and/or cardiovascular disease.