Changes of PPARγ protein expression and activity in peripheral blood lymphocytes of patients with sepsis

Objective To investigate the changes of PPARγ protein expression and activity of peripheral blood lymphocytes in patients with sepsis and its association with severity and prognosis of sepsis. Method Ac-cording to the guidelines to sepsis set by ACCP/SCCM consensus conference in 2003, 48 patients with sepsis ad-mitted in Emergency and Surgical ICU from December 2007 to March 2008 were enrolled in this perspective study. Sixteen healthy individuals were selected as controls. Patients with metastatic tumors, autoimmune disease, AIDS or under immunosuppressive therapy were excluded. This study was approved by the ethical committee of Zhong-shan Hospital, Fudan University. All patients were divided into mild and severe sepsis groups. Patients were also divided into survivor and non-survivor groups as per 28-day mortality. Peripheral blood lymphocytes were isolated by using Ficoll density gradient centrifugation. PPART protein expression was determined by using Westem Blot-ting. The activity of PPARγ was analyzed by using EMSA. Differences among groups were analyzed by using one-way ANOVA. Results The protein expression and activity of PPARγ were significantly increased in mild sepsis patients (0.56±0.12 and 4.13±0.22, respectively) compared with both healthy controls (0.39±0.07 and 2.42±0.17, respectively) and severe sepsis patients (0.30±0.07 and 1.63±0.12, respectively) (P < 0.05). However, the protein expression and activity of PPARγ were obviously decreased in severe sepsis patients compared with healthy individuals and mild spsis patients (P < 0.05). Survivors from sepsis had significantly higher protein expression and activity (0.54±0.11 and 3.59±0.34, respectively) than non-survivors (0.21±0.08 and 1.94 ±0.25, respectively) (P < 0.05). Conclusions These data suggest that the protein expression and activity of PPARγ in peripheral blood lymphocytes might be valuable biomarkers in assessing the severity and outcome of pa-tients with sepsis.