To review the role of hypoxia inducible factor 1α (HIF-1α) in hypoxic-ischemic injury and its repair, and to analyze the possible mechanisms. Methods Recent l iterature on HIF-1α and its role in hypoxic-ischemic injury was reviewed and analyzed. Results HIF-1α was involved in the hypoxic-ischemic injury of various organs or tissues and their repair processes. Conclusion HIF-1α has a potential to treat common cl inical hypoxic-ischemic injuries and has a promisingfuture for appl ication.
ObjectiveTo observe the effect of integrin β8 on the neuronal apoptosis after hypoxia ischemia (HI) in astrocyte/neuron co-culture system. MethodsAstrocytes and neurons were cultured in vitro from cerebral cortex of the P1-3 days Sprague Dawley rats and E16 days fetal rats, respectively. Immunocytochemistry staining was used to identify the purity of cells. Integrin β8 mRNA expression was qualified in the astrocytes at 12 hours, 1 day, and 2 days after HI and reoxygenation (experimental group) and in normal astrocytes (control group) by RT-PCR. Integrin β8 small interering RNA (siRNA) system was established to specifically block astrocyte β8 expression, the efficiency of integrin β8 inhibition was detected by real-time fluorescent PCR. The astrocytes and neurons were co-cultured to established the astrocyte/neuron co-culture system. The neuronal apoptosis was detected with TUNEL in the normal neurons/astrocytes group (co-cultured HI group), the astrocytes infected by integrin β8 siRNA for 2 days/normal neurons group (β8 RNA interference group), and normal neurons in vitro with HI treatment group (HI group) at 1 day after HI and reoxygenation. The normal neurons without treatment as control (control group). ResultsGlial fibrillary acidic protein and neuronal nuclei staining suggested a purity of more than 90% in cultured cells. HI resulted in an increase of integrin β8 mRNA expression at 12 hours after reoxygenation in astrocytes, which peaked at 1 day after reoxygenation, then slowly decreased and remained higher at 2 days, showing significant differences between control group and experimental group and among different time points in experimental group (P<0.05). RNA interference efficiency was most significant at 2 days after astrocytes infected with integrin β8 siRNA (P<0.05). The neuronal apoptosis was significantly increased in HI group, co-cultured HI group, and β8 RNA interference group when compared with control group (P<0.05). But neuronal apoptosis index (AI) was significantly decreased in co-cultured HI group and β8 RNA interference group when compared with HI group (P<0.05). The significant difference of AI was found between co-cultured HI group and β8 RNA interference group (P<0.05). ConclusionIntegrin β8 expression can be induced with hypoxic-ischemic brain damage, leading to decreased AI of neurons and obvious protective effect.
Objective To investigate the expression of hypoxia inducible factor 1(HIF1alpha;) in ratsprime; retinae during the embryonic and earlier postnatal period. Methods The retinal expression patterns of HIF-1alpha; protein and mRNA of embryonic day 12 (E12), E16, E20, and postnatal day 1(P1) and P5 rats were determined by immunohistochemical staining and reverse transcriptionpolymerase chain reaction (RT-PCR). Results HIF-1alpha; protein was detected in the neural epithelial layer and the pigment epithelial layer at all those 5 timepoints, with higher expression in the ganglion cell layer and the inner plexiform layer, and seems limited to the ganglion cell layer when re tina became more mature. Embryonic rat retina had higher expression of HIF-1alpha; protein and mRNA than postnatal retina, the difference was significant (P<0.01). Conclusion The expression of HIF1alpha; in ratsprime;retina e differs from embryonic to earlier postnatal stages.
ObjectiveTo elucidate whether hypoxia induced factor-1α (HIF-1α) gene improved hypoxia tolerant capability of bone marrow mesenchymal stem cells uptake(MSCs) or not and whether the capability was related to glucose uptake increase in hypoxia MSCs ex vivo or not. MethodsMSCs were randomly divided into normoxia non-HIF-1α transfection group (control group), normoxia HIF-1α transfection group, hypoxia non-HIF-1α transfection group, and hypoxia HIF-1α transfection group and then each group was cultured with normoxia (5% CO2 at 37 ℃) or hypoxia (94% N2, 1% O2, 5% CO2 at 37 ℃) for 8 h, respectively. Finally, the expressions of HIF-1α were detected by immunocytochemistry, RT-PCR, and Western blot methods, respectively. Apoptosis ratio (AR) and death ratio (DR) were tested by flow cytometry. The proliferation was detected by MTT method. Glucose uptake was assayed by radiation isotope method. Results① Compared with the normoxia non-HIF-1α transfection group, the expression of HIF-1α mRNA significantly increased (Plt;0.01) in the normoxia HIF-1α transfection group except for its protein (P=0.187); Both of mRNA and protein expressions of HIF-1α in the hypoxia HIF-1α transfection group were significantly higher than those in the hypoxia non-HIF-1α transfection group (Plt;0.01). ② The AR (P=0.001) and DR (P=0.003) in the hypoxia HIF-1α transfection group were significantly lower thanthose in the hypoxia non-HIF-1α transfection group, both of which were significantly higher than those in the normoxia non-HIF-1α transfection group (Plt;0.01). ③ The proliferation of MSCs in the hypoxia HIF-1α transfection group was significantly higher than that in the hypoxia non-HIF-1α transfection group (P=0.004), which significantly lower than that in the normoxia non-HIF-1α transfection group (P=0.001). ④ Compared with the hypoxia non-HIF-1α transfection group, the 3H-G uptake capability (P=0.004) of MSCs significantly increased in the hypoxia HIF-1α transfection group, which was significantly lower than that in the normoxia non-HIF-1α transfection group (P=0.001). ⑤ There were significantly negative relation between AR and HIF-1α protein (r=-0.71,P=0.005) or 3H-G uptake (r=-0.65,P=0.004), and significantly positive relation between HIF-1α protein expression and 3H-G uptake (r=0.77, P=0.003). ConclusionHIF-1α gene significantly improves anti-hypoxia capability of MSCs, which is fulfilled by increasing glucose upake.
目的 通過復制人肝癌細胞株HepG2裸鼠皮下移植瘤模型,觀察綠茶提取物表沒食子兒茶素沒食子酸酯(EGCG)干預對HepG2移植瘤新生血管生成的影響。 方法 瘤體接種復制HepG2移植瘤模型,荷瘤裸鼠20只隨機分組,實驗組給予EGCG溶液每日20 mg/(kg·只),腹腔注射3周,對照組給予等量滅菌注射用水3周,末次用藥24 h,后處死裸鼠,剝離移植瘤。常規病理切片觀察移植瘤組織結構;逆轉錄-聚合酶鏈式反應和免疫組織化學法檢測移植瘤缺氧誘導因子-1α(HIF-1α)、血管內皮生長因子(VEGF)mRNA及蛋白表達,并通過檢測CD34表達計數瘤組織微血管密度(MVD)。 結果 組織病理學觀察實驗組移植瘤見大量壞死區,瘤體內血管數量明顯少于對照組;實驗組HIF-1α、VEGF mRNA及蛋白表達水平比對照組均明顯下調(P<0.05),實驗組MVD比對照組明顯下降(P<0.05)。 結論 EGCG可抑制荷瘤裸鼠HepG2移植瘤新生血管生成。
ObjectiveTo objectively evaluate the effect and safety of naloxone for the treatment of moderate and severe neonatal hypoxia-ischemic encephalopathy (HIE). MethodsResearch articles published from inception to June 2015 on Cochrane library, PubMed, Web of science, Chinese Science and Technology Journal Full-text Database, Digital Full-text Journal Database and Chinese Journal Full-text Database were searched, which were relevant to naloxone in the treatment of moderate and severe neonatal HIE. And two authors extracted information via standardized data extraction form and assessed the quality of included studies independently. RevMan 5.2 software was used for Meta-analysis. ResultsAt last, 20 randomized controlled trials (involving 1 519 neonates; 783 in the treatment group and 736 in the control group) were included. The results of meta-analysis showed that the effect of naloxone for moderate and severe HIE was significantly superior to the control group[OR=5.07, 95%CI (3.61, 7.12), P < 0.000 01]. The neurobehavioral scores in neonates treated by naloxone after 5, 7, 10, and 14 days were higher than those in the control group[WMD=6.61 points, 95%CI (5.70, 7.51) points, P < 0.000 01; WMD=4.27 points, 95%CI (2.63, 5.91) points, P < 0.000 01; WMD=2.40 points, 95%CI (1.47, 3.34) points, P < 0.000 01; WMD=2.58 points, 95%CI (1.00, 4.16) points, P=0.001], respectively; while the neurobehavioral scores after 3-day treatment between the two groups had no statistically difference[WMD=0.00 points, 95%CI(-0.76, 0.77) points, P=0.99]. What's more, the disappeared time of clinical symptoms and signs (breathing improvement time, recovery time, convulsions disappearance time, and signs disappearance time) in naloxone group was superior to the control groups[WMD=-3.78 hours, 95%CI (-6.93, -0.64) hours, P=0.02; WMD=-9.66 hours, 95%CI (-14.25, -5.06) hours, P < 0.001; WMD=-2.81 hours, 95%CI (-5.28, -0.35) hours, P=0.03; WMD=-1.02 days, 95%CI (-1.84, -0.20) days, P=0.01], respectively. ConclusionsNaloxone has certain therapeutic on moderate and severe HIE. Further high-quality randomized controlled trials should be carried out to provide more reliable evidence.
短期進入高原從事高強度工作所致高原反應是值得探討的問題,查閱文獻,探討其病因及發病機理、臨床表現,總結國內外在診斷、預防及治療方面的經驗,探索一套可行、有效的預防及治療措施,具有重要的臨床意義。
ObjectiveTo investigate the anti-apoptotic effect of ginsenoside Rg1 in neonatal rats with hypoxia ischemia brain damage (HIBD), and to explore the possible signaling pathway involved in anti-apoptosis. MethodsForty-eight 10-day-old Sprague Dawley (SD) rats (weighing 17-21 g, male or female) were randomly allocated into 4 groups (12 rats in each group): sham-operation group (sham group), HIBD group (HI group), HIBD+ginsenoside Rg1 group (HI+Rg1 group), and HIBD+ginsenoside Rg1+U0126 group (HI+Rg1+U0126 group). SD rats in HI group, HI+Rg1 group, and HI+Rg1+U0126 group underwent ligation of the right common carotid artery (CCA) and hypoxic ventilation (8%O2+92%N2) for 2.5 hours to prepare the HIBD model, and rats in sham group underwent only separation of the right CCA. SD rats in HI+Rg1+U0126 group received intraventricular injection of 5 μL phosphate buffer saline (PBS) containing U0126 (25 μg/kg) at 1 hour before HIBD, and rats in the other three groups received intraventricular injection of PBS at the same time. The rats in HI+Rg1 group and HI+Rg1+U0126 group received intraperitoneal injection of 0.1 mL normal saline (NS) containing Rg1 (40 mg/kg) at immediate after HIBD, while rats in HI group and sham group received intraperitoneal injection of 0.1 mL NS at immediate after HIBD. At 4 and 24 hours after HIBD, the right hemisphere and hippocampus were collected to detect the protein expression and distribution of extracellular signal-related protein kinase 1/2 (Erk1/2), phospho-Erk1/2 (p-Erk1/2), hypoxia inducible factor 1α (HIF-1α), and cleaved Caspase-3 (CC3) by Western blot and immunohistochemistry staining. TUNEL staining was used to evaluate neural apoptosis in situ. ResultsWestern blot results showed that there were expressions of Erk1/2, p-ERK1/2, HIF-1α, and CC3 proteins at 4 and 24 hours after HIBD in each group. The expressions of HIF-1α and CC3 protein at 4 and 24 hours, and expression of p-Erk1/2 protein at 4 hours were significantly increased in HI group when compared with sham group (P < 0.05). When compared with HI group, the expressions of p-Erk1/2 and HIF-1α protein in HI+Rg1 group were significantly increased (P < 0.05), while the expression of CC3 protein was significantly decreased at 4 and 24 hours (P < 0.05). When compared with HI+Rg1 group, the expressions of p-Erk1/2 and HIF-1α proteins in HI+Rg1+U0126 group were significantly decreased (P < 0.05), while expression of CC3 protein was significantly increased at 4 and 24 hours (P < 0.05). There was no significant difference in Erk1/2 protein expression between groups at different time points (P > 0.05). Immunohistochemistry staining displayed that HIF-1α and CC3 proteins mainly distributed in the nucleus and cytoplasma, while Erk1/2 and p-Erk1/2 proteins mainly distributed in the cytoplasma. The expression levels of protein by immunohistochemistry results were similar to the results by Western blot. TUNEL staining showed that the apoptotic neurons were characterized by yellow or brown particle in the nucleus. The apoptotic index (AI) of neurons at 4 and 24 hours was significantly increased in HI group when compared with sham group (P < 0.05), and the AI of neurons was significantly decreased in HI+Rg1 group when compared with HI group and HI+Rg1+U0126 group at 24 hours (P < 0.05). ConclusionRg1 could enhance HIBD induced HIF-1α expression and inhibit activation of Caspase-3 by Erk1/2 signaling pathway, and play an anti-apoptotic role in neonatal rats with HIBD.