P2X7 Receptor Expression in Peripheral Blood Monocytes Is Correlated With Plasma C-Reactive Protein and Cytokine Levels in Patients With Type 2 Diabetes Mellitus: a Preliminary Report

Chronic inflammation plays a major role in development of type 2 diabetes mellitus (T2DM). C-reactive protein (CRP) and inflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha) and interleukin 1 beta (IL-1 beta) are directly involved in the occurrence of insulin resistance. Increased extracellular ATP levels can amplify the inflammatory response in vivo via the P2X(7) receptor. The present study aimed to assess the relationship between P2X(7) receptor expression in human peripheral blood monocytes and plasma levels of TNF-alpha, IL-1 beta, and CRP in T2DM patients. The results showed the association of increased P2X(7) receptor expression of monocytes with high serum CRP, TNF-alpha, and IL-1 beta levels. TNF-alpha and IL-1 beta levels were lowest in healthy subjects; in T2DM patients, these inflammatory markers were less abundant in individuals with normal CRP levels compared to those with high CRP contents. In contrast, IL-10 levels in T2DM patients with high CRP levels were dramatically decreased. P2X(7) receptor expression in monocytes from T2DM patients with high CRP levels was significantly increased in comparison with healthy individuals and T2DM patients with normal CRP levels. These findings indicated that P2X(7) receptor in peripheral blood monocytes may be involved in the pathological changes of T2DM, particularly affecting patients with high CRP levels.