山奈酚腹腔注射后脑出血大鼠脑组织神经炎症 反应及PI3K/AKT信号通路相关蛋白表达观察.

Objective To observe the neuroinflammatory response and the expression of PI3K/AKT signaling pathway-related proteins in brain tissues of rats with intracerebral hemorrhage (ICH ) after intraperitoneal injection of kaempferol in order to explore the inhibitory effect and mechanism of kaempferol on the neuroinflammatory response after ICH in rats. Methods Seventy-two SD rats were randomly divided into four groups： the kaempferol group, the kaempferol + PI3K inhibitor LY294002 group (inhibitor group), the ICH group, and the sham operation group, respectively. The model of ICH was established in the kaempferol group, and then kaempferol 20 mg/(kg. d) was injected intraperitoneally once a day for 3 consecutive days. In the inhibitor group, PI3K inhibitor LY294002(10 µL, 10 mmol/L) was injected into the lateral ventricle before ICH was induced, and the other steps were the same as those in the kaempferol group. After the ICH model was established, the rats in the ICH group were intraperitoneally injected with the same volume of normal saline once a day for 3 consecutive days. The ICH model was not established in the sham operation group, and the equal volume of normal saline was injected intraperitoneally with the same method as the ICH group. At the end of the treatment, the neuroinflammatory response of brain tissues in each group was observed, including the degree of neurological deficit (mNSS score), the proportion of water content in the brain tissues, the morphological structure of tissue around cerebral hematoma, the number and morphology of microglia in brain tissue, the expression levels of microglia marker Iba-1 and interleukin-1β(IL-1β), interleukin-6(IL-6) and tumor necrosis factor-α(TNF-α) in the brain tissues, and the expression of phosphatidylinositol 3 kinase (PI3K)/protein kinase B (AKT) signaling pathway-related proteins (P-PI3K/PI3K, PAKT/AKT, P-NF-κB p65/NF-κB p65) in the brain tissues. Results Compared with the sham operation group, the neurological function score and the proportion of water content in brain tissue increased (all P<0. 05), and the tissue arrangement around the hematoma was disordered, the intercellular space was enlarged, a large number of inflammatory cells and red blood cells were infiltrated, and activated microglia were observed under immunofluorescence, the relative expression of Iba-1 protein in brain tissue increased, and the expression levels of inflammatory factors such as IL-1β, IL-6 and TNF-α in the brain tissue increased in the ICH group (all P<0. 05). Compared with the ICH group, the nerve function score and brain tissue water proportion decreased (all P<0. 05), and brain tissue pathological morphology was improved, the microglia tended to resting state changes, Iba-1 protein expression was lower, and the expression levels of IL-1β, IL-6 and TNFα in the brain tissues decreased in the kaempferol group (all P<0. 05). Compared with the kaempferol group, the neurological function score and the proportion of water content in the brain tissues significantly increased, the tissues around the hematoma were more disorderly arranged, with more inflammatory cells and red blood cells infiltration and increased activated microglia, the relative expression of Iba-1 protein in brain tissue increased, and the levels of IL-1β, IL-6 and TNF-α in the brain tissues increased in the inhibitor group (all P<0. 05). Compared with the sham operation group, the P-PI3K/ PI3K and P-AKT/AKT decreased, and the P-NF-κB p65/NF-κB p65 increased in the ICH group (all P<0. 05). Compared with the ICH group, the ratios of P-PI3K/PI3K and P-AKT/AKT increased, and the ratio of P-NF-κb p65/NF-κB p65 decreased in the kaempferol group (all P<0. 05). Compared with the kaempferol group, the ratio of P-PI3K/PI3K and P-AKT/AKT decreased, and the ratio of the P-NF-κb p65/NF-κB p65 increased in the inhibitor group (all P<0. 05). Conclusions Intraperitoneal injection of kaempferol can reduce the neuroinflammatory response and activate PI3K/AKT signaling pathway in the brain tissues of rats with ICH. Kaempferol can effectively inhibit the neuroinflammatory response after ICH in rats possibly by regulating the PI3K/AKT signaling pathway. [ABSTRACT FROM AUTHOR]