Objective: To study the correlation between the plasma long non-coding RNA (lncRNA) maternally expressed gene 3 (MEG3) and the levels of inflammatory cytokines in patients with traumatic brain injury (TBI) and to evaluate its prognosis to screen new biological targets for the diagnosis and treatment of TBI.
Patients and methods: 40 patients with TBI (TBI group) and 40 healthy people (control group) were collected and venous blood was drawn. The plasma MEG3 in subjects was quantitatively analyzed via quantitative Polymerase Chain Reaction (qPCR). Moreover, the levels of inflammatory cytokines [tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, and IL-8] in plasma in each group were detected via enzyme-linked immunosorbent assay (ELISA). Finally, the correlation analysis was performed for the MEG3 expression level and inflammatory cytokine levels in patients with TBI. Patients were divided into high-expression MEG3 group and low-expression MEG3 group, high-level inflammatory cytokine group and low-level inflammatory cytokine group according to the median, followed by prognosis evaluation. The MEG3 expression level in TBI group was significantly decreased compared to that in control group, and the levels of inflammatory cytokines in plasma, including TNF-α, IL-1β, IL-6, and IL-8, were significantly higher than in control group.
Results: The results of the correlation analysis showed that the expression level of plasma MEG3 had a significantly negative correlation with the level of each inflammatory cytokine. The prognostic analysis revealed that the prognosis of patients with high MEG3 expression level and low inflammatory cytokine levels was good, while it was poor in patients with low MEG3 expression level and high inflammatory cytokine levels; the difference was significant. In patients with TBI, the expression level of plasma MEG3 is decreased, while the inflammatory cytokine levels are increased, and there is a significantly negative correlation between the two items.
Conclusions: The prognosis of patients with high MEG3 expression level and low inflammatory cytokine levels is good so MEG3 and inflammatory cytokines can be used as biomarkers for diagnosis and treatment of TBI, improving the prognosis of patients.