OBJECTIVE: METHODS: Mice were randomly divided into five groups the vehicle group, the middle cerebral artery occlusion (MCAO) group, the MCAO plus adenosine monophosphate-activated protein kinase ( AMPK) inhibitor compound C group, the MCAO plus IL-11 treatment group, and the MCAO plus IL-11 treatment and compound C group. Focal cerebral ischemia was induced by occluding the left middle cerebral artery, and reperfusion was achieved by withdrawing the suture 2 h after ischemia. The protein expression levels of IL-11 were measured using Western blot analysis, and its location was detected using immunohistochemistry and immunofluorescence staining. The infarct volume was examined using 2,3,5-triphenyl tetrazolium chloride (TTC) staining, and the neurobehavioral progression was assessed using the neurological scoring system. The expression of astrocytes and microglia was detected using immunochemistry, and real-time quantitative PCR was used for the gene quantification of inflammatory cytokines. The extent of cerebral ischemia- reperfusion injury was tested using Nissl staining and the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay. The expression of the apoptotic proteins Bax, Bcl-2 and cleaved caspase-3 were detected using Western blot analysis, and the oxidative stress was also measured. RESULTS: The expression of IL-11 mRNA and protein significantly decreased after cerebral ischemia. Immunohistochemical staining showed a large amount of IL-11 in the cerebral cortex of the mice in the vehicle group, whereas the immunoreactivity of IL-11 remained weak for 24 h in the MCAO group. Immunofluorescent staining further confirmed that IL-11 was mainly expressed in the neurons. It was suggested that IL-11 (20 μg/kg) treatment ameliorated infarction and reduced neurological scores. In addition, IL-11 proved to reduce neuropathic damage, glial activation, and the expression of proinflammatory cytokines and increase the expression of anti-inflammatory cytokines after cerebral ischemia. IL-11 was also able to alleviate oxidative stress caused by cerebral ischemia, and AMPK inhibition enhanced the alleviation. Moreover, IL-11 was found to inhibit apoptosis caused by cerebral ischemia, which could also be facilitated by AMPK inhibitors. SIGNIFICANCE:
|