ABSTRACT
Objective:To investigate the role of basic fibroblast growth factor (bFGF) in decreasing intracranial pressure in rats after intra-abdominal hypertension (IAH).Methods:A total of 60 healthy SD rats were selected for the experiment. Secondary IAH rat models were established by hemorrhagic shock/resuscitation, followed by injecting nitrogen into the peritoneal cavity of the rats to maintain an intra-abdominal pressure of 12mmHg and above. According to the random number table, the rats were divided into control group, IAH group, IAH+ bFGF group (bFGF group) and IAH+ bFGF+ PD173074 group (antagonist group), with 15 rats per group. Indicators were measured 4 hours after injury, including intracranial pressure, brain morphological observation, apparent diffusion coefficient (ADC) value, lactic acid content of brain MRI, brain water content and Evans blue exudation. Immunofluorescence staining, Western blotting and PCR were used to detect the expressions of phosphorylate-fibroblast growth factor receptor 1, 2 (p-FGFR1, 2), Zonula occludens-1 (ZO-1), β-catenin, matrix metalloproteinases 9 (MMP9), interleukin-1β (IL-1β) in brain microvascular endothelial cells (BMECs).Results:The intracranial pressure in IAH group [(5.52±0.45)mmHg] gradually increased 4 hours after injury compared control group [(3.36±0.30)mmHg]. Compared with IAH group, the intracranial pressurein bFGF group [(4.46±0.41)mmHg] was decreased ( P<0.05). Compared with bFGF group, the intracranial pressure in antagonist group [(5.36±0.44)mmHg] was enhanced ( P<0.05). Brain morphological observations in IAH group showed swelling and obvious cerebral edema, accompanied with a small amount of subarachnoid hemorrhage. Compared with IAH group, cerebral edema and brain swelling were relieved in bFGF group, while the antagonist group still showed cerebral edema and obvious brain swelling. At 4 hours after injury, MRI examination showed that the relative ADC value in IAH group (cortex: 0.82±0.11, corpus callosum: 1.26±0.17) was lower than that in control group (cortex: 1.00±0.13, corpus callosum: 1.43±0.15)( P<0.05). Compared with IAH group, the relative ADC value in bFGF group (cortex: 0.94±0.16, corpus callosum: 1.36±0.16) was increased ( P<0.05). Compared with bFGF group, the relative ADC value in antagonist group (cortex: 0.87±0.13, corpus callosum: 1.30±0.14) was decreased ( P<0.05). Relative lactic acid content in IAH group (cortex: 15.50±2.14, corpus callosum: 10.82±1.90)was higher than that in control group (cortex: 1.00±0.23, corpus callosum: 0.70±0.20)( P<0.05). Compared with IAH group, the relative lactic acid content in bFGF group (cortex: 10.85±1.42, corpus callosum: 6.96±1.30) was decreased ( P<0.05). Compared withbFGF group, the relative lactic acid content in antagonist group (cortex: 13.71±1.61, corpus callosum: 9.12±1.52) was increased ( P<0.05). The brain water content in IAH group [(87.9±0.8)%] was higher than that in control group [(76.3±0.9)%]. Compared with IAH group, the brain water content in bFGF group [(83.2±1.0)%] was decreased( P<0.05). Compared with bFGF group, the brain water content in antagonist group[(85.4±0.8)%] was increased ( P<0.05). Evans blue exudation in IAH group [(3.22±0.29)μg/ml] was greater than that in control group [(0.42±0.22)μg/ml]( P<0.05). Compared with IAH group, the Evans blue exudation in bFGF group [(2.04±0.25)μg/ml] was decreased ( P<0.05). Compared with bFGF group, the Evans blue exudation in antagonist group [(2.92±0.20)μg/ml] was increased ( P<0.05). Compared with control group, the expression of p-FGFR1 in BMECs in IAH group was weakened 4 hours after injury, but p-FGFR2 remained unchanged, the expressions of ZO-1, β-catenin protein and mRNA were weakened, and the expressions of MMP9, IL-1β protein and mRNA were enhanced ( P<0.05). Compared with IAH group, the expressions of p-FGFR1, ZO-1, β-catenin protein and mRNA were enhancedin bFGF group, and the expressions of MMP9, IL-1β protein and mRNA were weakened as well ( P<0.05). However, the expressions of p-FGFR1, ZO-1 and β-catenin protein and mRNA in antagonist group were weaker than those in bFGF group, and the expressions of MMP9 and IL-1β protein and mRNA were stronger than those in the bFGF group ( P<0.05). Conclusion:After IAH, the rat model presents damaged blood-brain barrier, increased cerebral edema, and increased intracranial pressure, and the use of bFGF can improve these symptoms. FGFR1 of BMECs is a key receptor for bFGF to play a protective role, and its receptor inhibitor PD173074 can attenuate the protective effect of bFGF.
ABSTRACT
Objective To investigate the effects of GGNBP2 on proliferation,migration and invasion of human gli-oma U251 cells and the potential mechanism. Methods U251 glioma cells were transfected with lentiviral vector carrying GGNBP2 to establish a stable overexperssion of GGNBP2 in U251 cell line. After verification of the efficiency of transfec-tion by real-time PCR, Western Blot, PCR and CCK-8 were applied to detect the proliferation of U251 cells. The Tran-swell chamber assay was applied to measure the migration and invasion of human U251 glioma cells. Western blot was applied to measure protein levels of AKT, p-AKT, PCNA and MMP9. Result The stable U251 glioma cell line overex-pressing GGNBP2 was successfully established. Compared with the control group, overexpression of GGNBP2 significant-ly inhibited the proliferation(P<0.05),invasion(57±6 vs. 203±6,205±7,F=512.4,P < 0.05)and migration (74±7 vs. 254±14,248±13,F=242.5,P<0.05) of U251 cells. The protein expression levels of p-AKT (F=45.4, P<0.05), PCNA (F=348.5, P<0.05) and MMP-9 (F=88.7, P<0.05) in GGNBP2 group were markedly decreased compared with the control group. Conclusion GGNBP2 may suppress the proliferation, invasion and migration of glioma though down-regulation of p-AKT, which in turn inhibits PCNA and MMP-9 expression.
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Objective To investigate the effects of peroxisome proliferator-activated receptor gamma (PPARγ) agonist pioglitazone on delayed neuronal death,apoptosis of neurocytes,and expression of intercellular adhesion molecule-1 ( ICAM-1 ) following traumatic brain injury (TBI) in rats.MethodsThirty-six Sprague-Dawley rats were randomized into sham injury group,control group and pioglitazone treatment group,with 12 rats in each group.TBI model was established by modified Feeney method.Treatment grouP received intragastric administration of pioglitazone at a dosage of 10 mg/kg,and the sham injury group and the control group were lavaged with isometric 0.2％ dimethyl sulphoxide.Paraffin sections of brain tissues collected at 48 hours after TBI were employed to observe delayed neuronal death,apoptosis of neurocytes and expression of ICAM-1 by Nissl staining,TUNEL staining and immunochemistry respectively.Results( 1 ) Cell loss rate of Nissl body in the treatment group [ ( 38.59 ± 1.97 ) ％ ]was significantly lower than that of the control group [ (51.25 ± 4.01 ) ％ ] ( P ＜ 0.05 ),but was higher than that of the sham injury group [ (8.65 ± 1.23 ) ％ ] ( P ＜ 0.01 ).(2) The number of apoptotic neurocytes of the treatment group (31.67 ± 4.76) was significantly lower than that of the control group (45.33 ± 4.68 ) ( P ＜ 0.05),but was higher than that of the sham injury group ( 16.83 ± 2.04 ) ( P ＜ 0.01 ).(3) The mean optical degree of ICAM-1 positive expression of the treatment group (0.26 ± 0.04) was significantly lower than that of the control group (0.31 ± 0.04) ( P ＜ 0.05 ),but was higher than that of the sham injury group (0.10 ± 0.02 ) ( P ＜ 0.01 ).ConclusionsThe PPARγagonist pioglitazone can reduce the apoptosis of neurocytes and protect neurons after TBI.Meanwhile,its suppression of ICAM-1 expression is probably a mechanism of the suppression of inflammatory reaction and neural protection.