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BACKGROUND: 8-Hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) can decrease brain temperature, which is the potential mechanism of its neuroprotection. OBJECTIVE; To investigate the effect of 8-OH-DPAT on hypoxia inducible factor 1 a in the brain tissue of rats with diffuse axonal injury, and to explore the underlying mechanism of 8-OH-DPAT exerting neuroprotection in rats of diffuse axonal injury. METHODS; The study was approved by the Laboratory Animal Ethical Committee of General Hospital of Northern Theater Command. Wistar rats were randomly assigned into four groups: Model group (n=35), constant temperature group (n=35), 8-OH-DPAT group (n-35) and normal group (n=7). Excepting the normal group, rat models of diffuse axonal injury were established according to Marmarou method. Rat models in the constant temperature and 8-OH-DPAT were intraperitoneally injected with 8-OH-DPAT, but those in the model and normal groups were intraperitoneally injected with physiological saline. The body temperature of rats in the constant temperature group was maintained at (37.0±0.5)°C using the blanket. The body temperature of rats was measured every 1 hour. Then, brain injury and hypoxia inducible factor 1a expression level were observed at 6, 12, 24, 72, and 168 hours after diffuse axonal injury in rats. RESULTS AND CONCLUSION: (1) Compared with the constant temperature and model groups, brain temperature was significantly lower in the 8-OH-DPAT group at 1 hour following modeling (P < 0.05), became lowest at 2 hours (P < 0.05), and then gradually increased. (2) Hematoxylin-eosin staining results revealed that brain injury was more serious in the model group, followed by constant temperature group, and lightest in the 8-OH-DPAT group. (3) Results of immunohistochemistry and ELISA showed that the expression level of hypoxia inducible factor 1a in the serum and brain tissue was lowest in the normal group. In the 8-OH-DPAT group, the expression level of hypoxia inducible factor 1a was increased at 6 hours after diffuse axonal injury, and peaked at 24 hours. Compared with the model group, the expression level of hypoxia inducible factor 1a in serum and brain tissue in the constant temperature and 8-OH-DPAT groups was significantly decreased (P < 0.05 or P < 0.01), especially the 8-OH-DPAT group (P < 0.01). (4) These results imply that 8-OH-DPAT decreases hypoxia inducible factor 1a expression in brain tissue of diffuse axonal injury rats by reducing brain temperature, alleviates the degree of nerve injury, and exerts a neuroprotective effect.
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BACKGROUND: The authors found a striking similarity between the qi and blood theory and nerve repair of spinal cord injury in terms of improving blood-oxygen microenvironment in tissues. The hypothesis is that electroacupuncture can improve the blood-oxygen microenvironment of the spinal cord and promote nerve regeneration by regulating hypoxia-inducible factor 1a and vascular endothelial growth factor signal transduction. OBJECTIVE: To investigate the effect of electroacupuncture intervention on the expression of hypoxia-inducible factor 1a and vascular endothelial growth factor in injured segments of spinal cord injury rats. METHODS: Totally 120 Sprague-Dawley female rats were enrolled to make spinal cord injury models by clamping the spinal cord (20 seconds) using a microvascular clamp. Rat models were then randomly divided into three groups: Ashi point group, Stomach Meridian of Foot-Yangming group and blank control group, 40 rats in each group. Electroacupuncture at two Aishi points or at both sides of Futu and Zusanli points was started on the 3rd day after modeling. Each rat was scored on the Basso, Beattie and Bresnahan locomotor rating scale at 1, 2, 3,4, and 5 weeks after intervention. Injured spinal cord specimens were then taken and observed histomorphologically. Hypoxia-inducible factor-1a and vascular endothelial growth factor protein and mRNA expressions were detected using immunohistochemistry staining, real-time fluorescence quantitative PCR and western blot assay. The study protocol was approved by the Animal Ethic Committee of the First Affiliated Hospital of Guangxi University of Chinese Medicine in China (approval No. 201712001). RESULTS AND CONCLUSION: The lower limb function score, hypoxia-inducible factor-1a and vascular endothelial growth factor gene and protein expression in the two electroacupuncture intervention groups were significantly higher than those of the blank control group. The number of neurons in Ashi point and Stomach Meridian of Foot -Yangming groups was significantly higher than that of the blank control group with the lapse of intervention time. Electroacupuncture intervention can effectively improve the lower limb function score of spinal cord injury rats, increase the number of neurons, and up-regulate the mRNA and protein expression of hypoxia-inducible factor-1 a and vascular endothelial growth factor, thus effectively promoting the neurological recovery of the spinal cord.
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Objective: To observe the effect of CoCl on the cisplatin sensitivity of human ovarian cancer SKOV3 cells, and to clarify the possible mechanism. Methods: The SKOV3 cells were Cultured in vitro and randomly divided into control group, CoCT group, cisplatin (DDP) group and CoCT combined with DDP (combination) group. The cells in CoCL group were Cultured in normal cell medium for 20 h after cultured in 200 pmol • L CoCL for 4 h, the cells in DDP group were cultured in normal cell medium containing 10 mg • L DDP for 24 h, and the cells in combination group were cultured in 10 mg • L DDP for 20 h after cultured in 200 //mol • L CoCl • for 4 h. The survival rates of SKOV3 cells in various groups were detected by MTT method, and the positive expression intensities of hypoxia-inducible factor-1 a ( HIF-la) and inducible nitric oxide synthase (iNOS) in the cells in various groups were detected by immunofluorescence method. Rhod 2-AM fluorescence probe was used to observe the levels of Ca in mitochondria in the cells in various groups. Western blotting method was used to observe the expression levels of cytochrome C (cyto C) cysteinyl aspartasc 3 (caspasc 3) and cleaved cysteinyl aspartasc 3 (cleaved caspase 3). Muse apoptosis assay kit was used to detect the apoptotic rates of cells in various groups. Results: Compared with control group, the survival rate of the cells in CoCI group had no significant change (P> 0.05). and the survival rates of the cells in DDP and combination groups were decreased ( P0. 05) . and the expression levels of cyto C. caspase 3 and cleaved caspase 3 in DDP group were increased significantly ( P < 0.05); comparexl with DDP group, they were lower than those in combination group ( P<0. 05). Comparexl with control group∗ the apoptotic rate of SKOV3 cells in DDP group was increased significantly (P<.0. 05); the apoptotic rate of SKOV3 cells in combination group was lowe'r than that in DDP group (P<0. 05). Conclusion: CoCI can redece the mitochondrial apoptosis of human ovarian cancer SKOV3 cells by inhibiting the DDP-inducexl enhancement of iNOS expression and dccrease the sensitivity of SKOV3 cells to cisplatin.
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Objective To investigate the difference of hypoxia-inducible factor 1a (HIF-1a) and vascular endothelial growth factor (VEGF) expression in endometrial cancer and para-carcinoma tissues, and to explore the clinical significance of hypoxia and the two proteins in the development and progression of endometrial cancer. Methods From Jan. 2011 to Dec. 2012, 128 patients with endometrial cancer underwent surgery in Tongji Hospital of Tongji University. The expression of HIF-1a and VEGF in cancer tissues and paired para-carcinoma tissues was detected using immunohistochemical method. The patients were followed up regularly, and the relationship between the expression of HIF-1a and VEGF and the prognosis of the patients was analyzed. The hypoxic cell model of human endometrial cancer was constructed to detect the expression of HIF-1a and VEGF proteins and observe the cell proliferation, invasion and apoptosis. Results The positive rates of HIF-1a and VEGF in cancer tissues were significantly higher than those in the para-carcinoma tissues (both P0.05). In the hypoxic cell model of human endometrial cancer, the expression levels of HIF-1a and VEGF were significantly increased, cell proliferation and invasion were significantly increased, and the cell apoptosis was significantly reduced (all P<0.05). Conclusion HIF-1a and VEGF are related to the progress of endometrial cancer, and positive expression of HIF-1a indicates a poor prognosis.
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Objective To evaluate the association between hypoxia inducible factor-1α (HIF-1α)gene 1772C/T polymorphism and coronary collateral circulation formation in the patients with coronary heart disease (CHD).Methods The databases of PubMed,Cochrane Library,CBM,CNKI,VIP and Wanfang databases were comprehensively retrieved.The retrieval time was from the database establishment to January 2017.The case control trials on the relationship between HIF-1α gene 1772C/T polymorphism and coronary collateral circulation formation were collected.The included trials were performed the meta analysis.Results A total of 5 articles were included in analysis with a sample amount of 1 355 cases.The meta analysis suggested that HIF-1α gene 1772C/T polymorphism in 5 genetic models had no significant correlation with coronary collateral formation in CHD patients.The odds ratio(OR) values and 95 ％CI in allele,dominant,recessive,homozygote and heterozygote models were 1.70(0.85-3.39),P=0.134;1.46(0.77-2.77),P=-0.251;1.73(0.75-3.99),P=0.197;1.73(0.74-4.03),P=0.204;1.00(0.72-1.37),P=0.988,respectively.Conclusion HIF-1α gene 1772C/T polymorphism might have no association with coronary collateral formation in CHD patients.
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Objective To observe the effect of HIF-1a/iNOS signaling pathway on myocardial ischemia-reperfusion injury in rat heart transplantation and the protective mechanism of N-acetylcysteine (NAC) on donor heart after cardiac transplantation in rats.Methods Eighty healthy male Lewis rats were randomly divided into 3 groups,the control group (0.3 ml saline was infused via inferior vena cava 30 min before donor harvest or implantation),NAC donor pretreatment group [NAC (30 mg/kg.w) was injected into the vena cava of donor rat 30 min defore donor harvest],and the NAC receptor pretreatment group (NAC 300 mg/kg.w was injected into the vena cava of the recipient rats 30 min before transplantation.The 30 min was injected into the vena cava of the recipient rats).A transplant model was established and the graft was obtained after 24 h transplantation.The expression of iNOS,HIF-1a and mRNA in cardiac muscle tissue was detected by immunohistochemistry and Real time-PCR.Results HIF-1a protein expression in graft myocardial tissue was significantly lower in NAC donor pretreatment and recipient pretreatment group compared with control group (P ＜0.05),the differences were statistically significant (2.72±0.17 vs.2.24±0.23 vs.3.14.±0.16,F=56.26,P =0.000).The iNOS protein expression in NAC donor pretreatment group,and NAC recipient pretreatment group were lower than that in the control group (1.52±0.18 vs.1.61±0.19 vs.3.30±0.18,F=232.345,P =0.000),the differences were statistically significant (P ＜ 0.05).24 h after transplantation,the differences in graft myocardial tissue HIF-1a and iNOS mRNA among the three groups were statistically significant (F=7.467,16.490,P=0.003,0.000).The expression of iNOS mRNA in the NAC receptor pretreatment group was significantly lower than that in the control group (P＜0.05).Conclusion HIF-1a/iNOS signaling pathway can regulate ischemia reperfusion injury in rat heart transplantation,and the protective effect of NAC on donor heart maybe mediated via this pathway.
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Objective To study the effect of gastrin on the proliferation and angiogenesis of human umbilical vascular endothelial (HUVE) cell in vitro.Methods The immunocytochemistry assay,realtime-PCR,and Western blot were used to detect the gastrin receptor (CCK-BR) expression in HUVE cells.After HUVE cells were treated with 10 and 100 nmol/L gastrin for 72 h,MTT and soft agar colony formation assay were used to test the cell proliferation rate and colony formation rate,and the vascular-like structures were observed by three-dimensional culture of HUVE cells.The half-ring and ring vascular numbers were counted with five random visions.The vascular endothelial growth factor (VEGF) and hypoxia-inducible factor-1a (HIF-1a) mRNA and protein levels in HUVE cells were detected by realtime PCR and ELISA assay respectively.Results HUVE cells expressed CCK-BR.After the treatment with 10 and 100 nmol/L gastrin,the cell proliferation rate was increased by 48.48％ and 82.82 ％ compared to the control group,and colony formation rate was increased to 31.33％ and 45.67 ％ as compared with 15.33％ in the control group(P＜0.01).Relative expression quantities of VEGF and HIF-1a genes were 2.3 and 4.6 folds (VEGF) and 20.76 and 26.77 folds (HIF-1 a) than those in the control group.The concentration of VEGF protein in culture medium was 221 and 392 μg/mg protein higher than that in control group.The numbers of half-ring and ring vascular structures were (14.00 ± 3.00,39.33 ± 7.57 and 34.33 ± 4.50)/vision and (8.33 ± 2.51,41.33 ± 5.85 and 37.67 ± 3.51)/vision in control,10 and 100 nmol/L gastrin-treated groups,respectively (P＜0.01).Conclusion Gastrin up-regulates the expression of VEGF and HIF-1a genes in HUVE cells and promotes cell proliferation and vascular-like structure formation of HUVE cells in vitro by being combined to CCK-BR,which may be involved in the development and metastasis of gastric cancer.
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Objective To study the function of hypoxia mimics of different exposure time of deferasirox in improving the growth of micrangium in a narrow pedicle flap.Methods Fourty male SD rats were divided into 2 groups:experimental group was fed with deferasirox 100 mg/kg per day from 1d,3d,5d and 7d,respectively,before the surgery of transferring the narrow pedicle flap,while control group just fed with saline.After 7 days,the immunohistochemistry,Western blot and quantitative reverse transcription-PCR (qPCR) were performed to examine the expression of CD34.qPCR was used to examine the expression of HIF-1α,VEGF in order to investigate the regulatory effect of deferasirox in improving the growth of micrangium and the distinction among the different exposed time of deferasirox in the narrow pedicle flap.Results The deferasirox group exhibited a marked improvement in flap healing time,and with the increasing administration time of deferasirox,the expression of MVD,HIF-1α and VEGF was improved in each treated group (P＜0.05).Conclusions Deferasirox can induce HIF-1α secretion and increase CD34 expression,and so deferasirox can protect endothelial cells from hypoxic and ischaemic injury.