Objective: To investigated the circulating microRNA expression profile in sepsis and its clinical evaluation.
Methods: 70 patients with sepsis and 30 patients with SIRS were selected and their blood samples were collected. Using liquid bead array with 3 statistical analysis approaches analyzed the circulating microRNA expression profiles, for confirming the data of liquid bead array, qRT-PCR was performed. The prognostic value of the changed microRNA in sepsis was determined and compared with CRP and PCT by analyzing the receiver operating characteristic (ROC) curves. To reveal whether the selected microRNAs could predict the outcome of patients, 28 d survival rate were calculated using Kaplan-Meier curves. Furthermore, the level of malondialdehyde (MDA), activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in plasma were detected and the relationship with the changed microRNA was determined.
Results: By integrating data from liquid bead array, we ultimately identified 6 microRNAs that were consistently changed in both of 3 statistical analysis approaches, however, only the change of microRNA-25 was significant according to the qPCR's result. The area under ROC curve showed that the clinical accuracy of microRNA-25 for sepsis diagnosis was better than CRP and PCT (AUG=0.806, 0.676 and 0.726, P<0.05).The decrease in level of microRNA-25 was correlated with the severity of sepsis, SOFA score, CRP and PCT level, meanwhile, microRNA-25 level can be used for predicting the prognosis of patients, the patients with microRNA-25 level ≤0.492 had a lower 28 d survival rate. Moreover, Decreased microRNA-25 level was related to the level of oxidative stress indicators in sepsis patients.
Conclusions: MicroRNA-25 can be used as a biomarker for the diagnosis and assessment of sepsis. Meanwhile, microRNA-25 level may be associated with oxidative stress in patients with sepsis, and it is expected to become a target for anti-oxidation therapy.
Keywords: Sepsis; biomarker; circulating microRNA; diagnosis; liquid bead array; oxidative stress; prognosis.