ABSTRACT
Objective To investigate the protective effect of Limb ischemic postconditioning ( LIPostC) on blood brain barrier (BBB) and explore the influence on the the expression of tight junction protein claudin-5,occludin in cerebral ischemia-reperfusion injury of mice.Methods Ninety male CD1 mice were divided into three groups randomly:Sham-operated group(sham group), ischemia-reperfusion group(I/R group) and LIPostC group.Mouse middle cerebral artery cerebral ischemia-reperfusion model was established by modified-occlusion method. Neurological deficit scores, brain water content, infarct volume, BBB dysfunction were measured at 24 h after reperfusion.Western blot and RT-qPCR were used to analyze the expressions of claudin-5, occludin.Results Compared with I/R group, neurological deficits scores were significantly decreased, brain edema was relieved, infarct volume was reduced, and the expression of claudin-5, occludin up-regulated, the differences were statistically significant(all P<0.05).Conclusion LIPostC can protect the BBB of cerebral ischemia-reperfusion injury mice by increasing the expression of claudin-5,occludin, and that will provide a theoretical basis for its clinical application.
ABSTRACT
BACKGROUND: Interleukin-1 (IL-1β) and intercellular adhesion molecule-1 (ICAM-1 ) can mediate neutrophilic infiltration, which is closely relevant to cerebral ischemia-reperfusion injury.OBJECTIVE: To investigate the effect of physcion on cerebral inflammatory reaction after ischemia-reperfusion injury.DESIGN: A completely randomized study based on animals.SETTING: Neurological department in a university hospital.MATERIALS: From September to December 2003, the study was conducted in the Animal Laboratory, Hebei Staff and Workers Medical College. Totally 91 healthy male SD rats, supplied by Laboratory Animal Center of Hebei Medical University, were used in the experiments. They were divided into sham operation (SO) group, ischemia-reperfusion group, normal control group, 20 mg/kg physcion group and 40 mg/kg physcion group.Each of the former two groups would be divided into 4 subgroups named as the 6th-hour-after-reperfusion group, the 12th-hour-after-reperfusion group, the 24th-hour-after-reperfusion group and the 48th-hour-after-reperfusion group. Each of the latter two groups were divided into 2 subgroups named as the 12thhour-after-reperfusion group and the 24th-hour-after-reperfusion group. Each subgroup contained 7 rats.INTERVENTIONS: Middle cerebral artery occlusion model (MCAO model) was applied, and IL-1β was measured by radioimmunoassay and ICAM-1 was detected by immunohistochemical staining.MAIN OUTCOME MEASUREMENTS: The IL-1 β level and the positive expression of ICAM-1 in the rats' cerebella were observed.RESULTS: Cerebral ischemia-reperfusion injury in the rats reached its peak 6 hours after reperfusion, and then it decreased gradually. In the 12-hour-after-reperfusion subgroup amd the 24-hour-after-reperfusion subgroup of the 40 mg/kg physcion group, and the 12-hour-after-reperfusion subgroup of the 20 mg/kg physcion group, IL-1β in the injured parts of the cerebella decreased dramatically, compared with MCAO model controls ( P＜ 0.01 ). In the normal control group and SO group, a small quantity of ICAM-1 was detected in rat' s cerebral cortex, and some fulvous staining substance was observed in the plasma and membrane of cerebral vascular endothelium cells. In the cerebral ischemia-reperfusion injury group, positive staining substance could be observed 24 hours after the reperfusion, then darkened gradually (integral absorbency value: 31.89 ± 4.38, area density value: 0. 018 5 ± 0. 003 1). In the 12-hour-after-reperfusion subgroup of the 40 mg/kg physcion group (integral absorbency value: 13.33 ±6. 12, area density value: 0. 007 6 ± 0. 002 2) and the 24-hour-after-reperfusion subgroup of the 40 mg/kg physcion group (integral absorbency value: 20.04 ±4.65,area density value: 0. 012 9 ±0. 003 6), and in the 24-hour-after-reperfusion subgroup of the 20 mg/kg physcion group (integral absorbency value:23.73 ±4.51 area density value: 0. 014 1 ±0. 003 8), expressions of ICAM-1 around the infarctions significantly decreased as compared with those in the MCAO model controls respectively ( P ＜ 0.01 or P ＜ 0.05).CONCLUSION: Physcion tends to decrease the expressing of IL-1β and ICAM-1 in a cerebellum after ischemia-reperfusion injury, thus, it may help alleviate the ischemia-reperfusion injury.
ABSTRACT
AIM: To explore the effect of physcion (P) on the level of IL-1? and expression of ICAM-1 and caspase-3 during cerebral ischemia-reperfusion injury. METHODS: The 91 healthy adult SD rats were selected, and were randomly divided into normal group, sham-operated group, cerebral ischemia-reperfusion group (model), low-dose physcion (PLD) and high-dose physcion (PHD) treatment group. The level of IL-1? was detected by radioimmunoassay. The expression of ICAM-1 and caspase-3 was detected by immunohistochemistry. The changes of tissue pathology were also investigated. RESULTS: The level of IL-1? reached the peak at 6 h after ischemia-reperfusion (IR). The protein expression of ICAM-1 and caspase-3 reached the peak at 24 h after IR. The level of IL-1? and the protein expression of ICAM-1 and caspase-3 in PHD group decreased obviously compared with those in model group (P