[Effects of dexamethasone on MRL/lpr mice with systemic lupus erythematosus complicated with cognitive dysfunction].

OBJECTIVE: To evaluate the effects of dexamethasone on systemic lupus erythematosus complicated with cognitive dysfunction.
 Methods: Ten wild type mice and 20 MRL/lpr mice were applied for the research. MRL/lpr mice were randomly assigned to a MRL/lpr group and a MRL/lpr + dexamethasone (1.5 mg/kg) group. Interleukin-6 (IL-6), IL-1β, and tumor necrosis factor alpha (TNF-α) in serum and hippocampus were detected. The protein phosphorylation levels of phosphoinositide 3-kinase (P-PI3K), protein kinase B (P-Akt), NF-kappa-B inhibitor alpha (P-IκBa) and nuclear transcription factor 
kappa-B p65 (P-NF-κB p65) were detected by Western blot, the level of P-NF-κB p65 also was detected by immunohistochemistry. 
 Results: Treatment with dexamethasone (1.5 mg/kg) alleviated the cognitive dysfunction and decreased the levels of IL-6, IL-1β and TNF-α in serum and hippocampus, and reduced the levels of P-PI3K, P-Akt, P-IκBa and P-NF-κB p65 in hippocampus in MRL/lpr mice.
 Conclusion: Dexamethasone may play a protective role in the cognitive function by decreasing the levels of TNF-α and IL-1β in the hippocampus of MRL/lpr lupus mice.