Expression of Leukemia Inhibitory Factor in Airway Epithelial Tissue of Asthmatic Rats

In order to investigate the expression of leukemia inhibitory factor(LIF) in airway epithelial tissues of normal and asthmatic rats,the influence of dexamethasone and the role of LIF in pathogenesis of asthma,30 Sprague-Dawley(SD) rats were randomly divided into 3 groups(10 for each group):normal group,asthma model group,and dexamethasone-interfered group.In asthma model group and dexamethasone-interfered group,asthma rat models were established by intraperi-toneal(i.p.) injection of 10% ovalbumin(OVA) and challenge with 1% OVA via inhalation.Rats in dexamethasone-interfered group were pretreated with dexamethasone(2 mg/kg,i.p) 30 min before each challenge.The expression of LIF protein in lung was detected by immunohistochemistry.The results showed that LIF protein was mainly expressed in cytoplasm of bronchial epithelial cells.The expression of LIF protein in the airway epithelial tissue of asthma model group was significantly higher than that in normal group and dexamethasone-interfered group(P<0.01),but there was no sig-nificant difference between normal group and dexamethasone-interfered group(P>0.05).It was con-cluded that the expression of LIF was increased significantly in the airway epithelial tissue of the asthma rats,and dexamethasone could down-regulate the expression of LIF.It was suggested that LIF might play an important role in the pathogenesis of asthma as an inflammation regulator.     

Expression of Nuclear Factor-Kappa-B in Mouse Enometrium Treated with Different Levels of Estridiol or Progesterone

Objective To investigate the effect of estridiol nuclear factor-kappa-B （NF-kB） expression in and progesterone at different levels on mouse endometrium Methods Ovarioectmized mice were randomly divided into 9 groups, i.e. groups of sham operation, of estridiol only, of progesterone only and of progesterone combined with estridiol. Mice in the experimental groups accepted subcutaneous injections of estridiol or progesterone at different levels for one week. Their uteri were collected to detect the expression of NF-kB by immunohistochemical assay. Results Estridiol at a daily dose of 30 μg/kg and 100 μg/kg could significantly stimulate the expression of NF-kB in mouse endometrium（P〈0.01）, but not in an obvious dose-dependent fashion （P〉0.05）. Progesterone alone could inhibit the expression of NF-kB in cytoplasma （P〈0.01）. Combination of estridiol and progesterone could increase NF-kB expression both in cytoplasma and nuclear （P〈0.01）. Conclusion Eestridiol can up-regulate the expression of NF-kB in mouse endometrium, while progesterone exhibits down-regulation effect. This finding suggests that estridiol and progesterone might modulate the endometrium receptivity by affecting NF-kB pathway.     

Impact of genetic variation of tumor necrosis factor-α on gestational hypertension

Background The mechanisms responsible for the pathogeneses of gestational hypertension and preeclampsia are unclear. Tumor necrosis factor-1α （TNF-1α） is a pro-inflammatory Th1-type cytokine. TNFA gene is located in the human leukocyte antigen （HLA） class Ⅲ region of the major histocompatibility complex （MHC） on chromosome 6. The high TNF-1α mRNA expression may be associated with the TNF2 （A） allele, which is the polymorphism of TNF-1α at position - 308 in promoter region. This study assessed whether the TNF2 （A） allele at position -308 plays a role in the alteration of blood pressure （BP） and urinary protein excretion during pregnancy. Methods The original prospective cohort study comprised 1623 pregnant women from January 2000 to October 2001. The G/A polymorphism was done by restriction fragment length polymorphism （RFLP） analysis with Nco I enzyme. Results The distributions of the G/A polymorphism of TNF-1α in the promoter region at position -308 were wild-type 72.4% and variant 27.6%, respectively. The frequency of TNF2 （A） allele was approximately 0.15 for Caucasian pregnant women in the study. It was not significantly different in the distributions of genotypes and G/A allele frequencies among the three groups of pregnant women with gestational hypertension, preexisting hypertension and normal blood pressure （P〉0.05）. The maternal blood pressure in the third trimester was significantly higher in the group of women possessing the TNF2 （A） allele compared to homozygous for the TNF1 （G） allele （systolic BE P〈0.01 and diastolic BE P〈0.05）. The elevated blood pressure in the TNF2 （A） group was accompanied by higher urinary protein excretion in the third trimester （P〈0.05）. The blood pressure and urinary protein excretion did not change apparently between the two groups in the first and second trimesters （P〉0.05）. Conclusions Maternal TNF2 （A） allele of TNF-1α promoter region at position -308 could play a role in the alteration of blood pressures and/or enhancement of urinary protein excretion during pregnancy, and might play an important role in the development of both gestational hypertension and preeclampsia.     

Experimental study of changes of TNF-α in rabbits with steroid-induced avascular necrosis of femoral head

INTRODUCTION Avascularnecrosisoffemoralhead(ANFH)isawell recognizedconditionofunknownaetiology wherebythecirculationofthebloodtofemoralheadis impaired.Eventuallytheinvolvedareaofbonediesand necrosisdevelops.Itmaybeidiopathicorassociated withsomediseases,suchastrauma,useofsteroids.ANFHinducedbysteroidisgettingmoreandmorewith theunreliableapplicationofsteroidinclinic.However,theexactmechanismofitsoccurrence,sofar,is uncertain.Theexperimenttriestoexploretheeffectof tumornecrosisfactorα(…     

Studies on Structural Changes of Collagen in Silicosis

In order to provide scientific information on the prevention and treatment of silicosis,studies about changes of silicotic collagen in lungs were carried out.In this paper,we present experiments about the structural changes of collagen in silicotic lungs of rats and patients.These included clectron microscopy,circular dichroism and infrared spectroscopy studies of collaeen fibers.The results indicated that fibers of silicotic collagen were shorter in length.smaller in diameter and decreased in α-helix content,The Si-O-R-group and -OH group were found increased and -C-C-backbone shortened.The increase of -Si-O-R-group indicated that silica formed linking bridgen between collagens whih may be the cause of progressive enlargement of nodules.     

Effects of allitridin on the expression of transcription factor T-bet mRNA of cytomegalovirus-induced myocarditis in mice

INTRODUCTIONT he cardiovascular disease myocarditis is character ized by inflammation and necrosis of cardiac mus cle. The disease ranges from transient inflammation to afulminant syndrome with manifestations that may includeheart failure, arrhythmias, and sudden death. This dis ease has been associated with various viral etiologies.Although enterovirus infections are recognized as a lead ing cause of myocarditis, at the present studies havedemonstrated that cytomegalovirus…     

Molecular analysis of signaling events mediated by the cytoplasmic domain of leukemia inhibitory factor receptor α subunit

A chimeric receptor (130/190) containing the cytoplasmic region of leukemia inhibitory factor receptor a sub-unit (LIFRα, or gp190) and the extracellular transmembrane region of gp130 was generated. Expressed of the 130/190 chimera in HL-60 cells to induced the     

Expression of OPGmRNA and ODFmRNA in the patients of hip fracture due to osteoporosis

Objective：To investigate the gene expression of osteoprotegerin（OPG） and osteoclast differentiation factor（ODF） in the bone tissue of patients with hip fracture due to osteoporosis. Methods：OPGmRNA and ODFmRNA in the bone tissue in 50 cases of osteoporosis sufferers（over 50 years old） with hip fracture（Observer Group） and 30 cases of hip facture sufferers with no osteoporosis（Control group） were analyzed with the Semi-Quantitative RT-PCR method. Results：The mRNA expressed of ODF, OPG were both high in the patients with hip fracture. In the control group, the expression of OPG mRNA was observed, while the expression of ODF mRNA was very slight. Conclusion：Aged patients contained all signals including OPG, ODF that are essential for inducing osteoclastogenesis and promoting bone resorption.     

Effects of Platelet Factor 4 on Expression of Bone Marrow Heparan Sulfate in Syngenic Bone Marrow Transplantation Mice

Platelet factor 4 ( PF4) is a negativehematopoietic factor.It can inhibit the prolifera-tion of endothelial cells and hematopoietic stem/progenitor cells,particularly megakaryoryocyticcells,reversibly[1] ,inhibit DNA synthesis,blockcell cycle progression during S phase and reducethe sensibility of normal hematopoietic stem/pro-genitor cells,but not some cancer or leukemia celllines,to cytotoxic drugs and ionizing radia-tion[2 - 3] ,and it also can cause a population in-crease of the stem cel…     

Inhibition of Expression of Hypoxia-inducible Factor-1αmrna by Nitric Oxide in Hypoxic Pulmonary Hypertension Rats

Summary: In order to study the effect of nitric oxide (NO) on the expression of hypoxia-inducible factor-1 alpha (HIF-la) mRNA in hypoxic pulmonary hypertension (HPH) rats, 30 healthy male Wistar rats were randomly divided into normoxic control group, chronic hypoxic group and hypoxia plus L-argine (L-Arg) group. The animal model of HPH was developed. The mean pulmonary arterial pressure (mPAP) was measured by inserting a microcatheter into the pulmonary artery. The HIF-1α mRNA expression levels were detected by in situ hybridization (ISH) and semiquantitative RT-PCR. It was found that after 14 days hypoxia, the mPAP in normoxic control group (17.6±2. 7 mmHg,1 mmHg=0. 133 kPa) was significantly lower than that in chronic hypoxic group(35.8±6.1 mmHg, t=0. 2918, P＜0.05) and mPAP in chronic hypoxic group was higher than that in hypoxia plus L-argine group(24.4±3.8 mmHg, t==0. 2563, P＜0. 05). ISH showed that the expression of HIF-lα mRNA in the intraacinar pulmonary arteriolae (IAPA) in normoxic control group (0. 1076±0. 0205) was markedly weaker than that in chronic hypoxic group (0. 3317 ± 0.0683, t=3. 125, P＜0. 05) and that in chronic hypoxic group was stronger than that in hypoxia plus L-argine group (0. 1928±0. 0381, t=2.844, P＜0.05). RT-PCR showed that the content of HIF-lα mRNA in chronic hypoxic group (2. 5395±0. 6449) was 2.16 times and 1.75 times higher than that in normoxic control group (1. 1781±0. 3628) and hypoxia plus L-argine group (1. 4511±0. 3981), respectively. It is concluded that NO can reduce the mPAP by the inhibition of the expression of HIF-1α mRNA, which may be one of the mechanisms through which NO affects the pathogenesis of HPH.     

Inhibitory Effect of HCPT on Expression of HIF-1α and Downstream Genes in Hypoxic Human Cervical SiHa Cancer Cells

The hypoxic model to simulate hypoxic microenvironment in solid tumors was established and the effect of hydrocamptothecin （HCPT） on the hypoxia-induced over-expression of HIF-1α and VEGF genes was explored. Human cervical cancer SiHa cells were cultured in vitro under hypoxic conditions （37℃, 5% CO2, 1%O2） and treated with different concentrations of HCPT for 24 h. The mRNA and protein expression levels of HIF-1α, VEGF and Glutl in SiHa cells were detected by semi-quantitative RT-PCR and Western blot respectively. Normoxic control groups were exposed to normoxic conditions for 24 h. Under normoxic conditions, HCPT had no obvious effects on the HIF-1α and VEGF gene expression. Hypoxia induced the up-regulation of HIF-1α protein and downstream VEGF gene, and HCPT showed a dose-dependently inhibitory effect on the hypoxia-induced over-expression of HIF-1α protein and VEGF gene expression in SiHa cells, whereas HCPT had no significant effect on the HIF-1α mRNA expression. No difference in HCPT cytotoxic- ity was observed between hypoxic groups and normoxic control groups. It was suggested that HCPT could inhibite the expression of HIF-1α protein and downstream VEGF gene in hypoxic SiHa cells in a dose-dependent manner, and the inhibitory effect was not related with HCPT cytotoxicity.     

Up-regulation of HIF-1α and VEGF Expression by Elevated Glucose Concentration and Hypoxia in Cultured Human Retinal Pigment Epithelial Cells

Summary： In order to explore the effect of high glucose concentration and high glucose concentration with hypoxia on the production of hypoxia-inducible factor-1α （HIF-1α） and vascular endothelial growth factor （VEGF）, human RPE cells were cultured in 5,56 mmol/L glucose （control group）, 5.56 mmol/L glucose with 150 !a mol/L COCl2 （hypoxic group）, 25 mmol/L glucose （high glucose group） and 25 mmol/L glucose with 150 μmol/L COCl2 （combination group）. RT-PCR was used to detect the expression of HIF-1α and VEGF mRNAs. Western blot analysis was used to measure the levels of HIF-1α and VEGF proteins. Although the small amount of HIF-1α protein was able to be detected in high glucose group but not in control group, there was no significant difference between the expression of HIF-1α mRNA of RPE cells in high glucose group and that of RPE cells in control group. As compared with RPE cells in control group, the mRNA expression and the protein synthesis of VEGF in high glucose group were up-regulated. As compared with RPE cells in hypoxic group, the expression of HIF-1α mRNA of RPE cells in combination group was not different, but the protein synthesis of HIF-1α, the mRNA expression and the protein synthesis of VEGF were more obviously up-regulated. In conclusion, high concentration glucose mainly influence the protein synthesis of HIF-1α of RPE cell, and HIF-1α protein is able to be accumulated in high concentration glucose. Under hypoxia, the HIF-1α protein induced by high concentration glucose is more stable, and the expression of VEGF is obviously increased. It is suggested that high concentration glucose may play a role in retinal neovascularization, especially at ischemia stage of diabetic retinopathy.     

Hypoxia-inducible factor-1 alpha regulates the role of vascular endothelial growth factor on pulmonary arteries of rats with hypoxia-induced pulmonary hypertension

Background Hypoxia-inducible factor-1α (HIF-1α) is one of the pivotal mediators in the response of lungs to decreased oxygen availability, and increasingly has been implicated in the pathogenesis of pulmonary hypertension. Vascular endothelial growth factor (VEGF), a downstream target gene of HIF-1α, plays an important role in the pathogenesis of hypoxic pulmonary hypertension and hypoxic pulmonary artery remodelling. In this study, we investigated the dynamic expression of HIF-1α and VEGF in pulmonary artery of rats with hypoxia-induced pulmonary hypertension. Methods Forty male Wistar rats were exposed to hypoxia for 0, 3, 7, 14 or 21 days. Mean pulmonary arterial pressure (mPAP), vessel morphometry and right ventricle hypertrophy index (RVHI) were estimated. Lungs were inflated and fixed for in situ hybridisation and immunohistochemistry. Results mPAP values were significantly higher than the control values after 7days of hypoxia ［(18.4±0.4) mmHg, P&lt;0.05］. RVHI developed significantly after 14 days of hypoxia. Expression of HIF-1α protein increased in pulmonary arterial tunica intima of all hypoxic rats. In pulmonary arterial tunica media, HIF-1α protein was markedly increased by day 3 (0.20±0.02, P&lt;0.05), reached the peak by day 7, then declined after day 14 of hypoxia. HIF-1α mRNA increased significantly after day 14 of hypoxia （0.20±0.02, P&lt;0.05）. VEGF protein began to increase markedly after day 7 of hypoxia, reaching its peak around day 14 of hypoxia (0.15±0.02, P&lt;0.05). VEGF mRNA began to increase after day 7 of hypoxia, then remained more or less stable from day 7 onwards. VEGF mRNA is located mainly in tunica intima and tunica media, whereas VEGF protein is located predominantly in tunica intima. Linear analysis showed that HIF-1α mRNA, VEGF and mPAP were correlated with hypoxic pulmonary artery remodelling. HIF-1α mRNA was positively correlated with VEGF mRNA and protein (P&lt;0.01). Conclusion HIF-1α and VEGF are both involved in the pathogenesis of hypoxia-induced pulmonary hypertension in rats.     

Effect of HIF-1α on VEGF-C Induced Lymphangiogenesis and Lymph Nodes Metastases of Pancreatic Cancer

The effect of hypoxia inducible factor-1α(HIF-1α) on vascular endothelial growth factor C (VEGF-C) and the correlation between HIF-1αand lymphangiogenesis and lymph nodes metasta-ses (LNM) in pancreatic cancer were investigated. Immunohistochemical SP method was used to detect the protein expression of HIF-1αand VEGF-C, and Lymphatic vessel density (LVD) was determined by stain of VEGFR-3, collagen type IV in 75 pancreatic head cancers from regional pancre-atectomy (RP) during Dec. 2001 to Dec. 2003. The relationship between HIF-1αand VEGF-C, lymphangiogenesis, LNM was analyzed statistically. The results showed that the positive expression rate of HIF-1αand VEGF-C in pancreatic cancer tissues was 48.00 % (36/75) and 65.33 % (49/75) respectively. In positive group of HIF-1α, the positive rate of VEGF-C and LVD, and LVD rate was 80.56 % (29/36), 13.22±3.76 and 88.89 % (32/36) respectively, and in negative group of HEF-1α, positive rate of VEGF-C and LVD was 51.28 % (20/39), 5.98±2.17 and 66.67 % (26/39) respectively (P<0.01 or P<0.05). It was suggested that HIF-1αcould promote the expression of VEGF-C, lymphangiogenesis and LNM in pancreatic cancer.     

Hypoxia Down-regulates Secretion of MMP-2, MMP-9 in Porcine Pulmonary Artery Endothelial and Smooth Muscle Cells and the Role of HIF-1

Summary： Primary cell culture, techniques of gene transfection, gelatin zymography, and Western blot were used to investigate the effect of hypoxia on the secretion of MMP 2 and MMP-9 in pulmonary artery endothelial cells （PAEC） and smooth muscle cells （PASMC）, and the role of HIF-1. Our results showed that （1） after exposure to hypoxia for 24 h, the protein content and activity of MMP-2 in the PAEC medium as well as these of MMP-2 and MMP-9 in PASMC medium （P〈0. 01 ） decreased significantly in contrast to those in normoxic group （P（0.05） ; （2） after transfection of wild type EPO3＇ enhancer, a HIF-1 decoy, the content and activity of MMP 2 and MMP-9 in hypoxic mediums became higher than those in normoxic group （P〈0. 01）, while transfection of mutant EPO3＇-enhancer didn＇t affect the hypoxia-induced down-regulation. It is concluded that hypoxia could inhibit the secretion and activity of MMP 2 and MMP-9 in PAEC and PASMC, which could he mitigated by the transfection of EPO3 ＇-enhancer and that H1F-1 pathway might contribute to hypoxia-induced down regulation of MMP-2 and MMP-9.     

内源性硫化氢在大鼠低氧性肺动脉高压中的作用

目的 :观察低氧性肺动脉高压 (HPH)时 ,内源性硫化氢生成的变化以及应用外源性硫化氢处理对HPH的影响 ,探讨气体分子硫化氢在HPH发病中的作用。方法 :Wistar大鼠随机分为对照组 (n =6 )、低氧组 (n =7)和低氧 +NaHS组 (n =6 )。低氧处理采用吸入氧浓度为 10 % (体积分数 )的气体 ,每天低氧 6h ,共持续 3周。低氧 +NaHS组大鼠每天低氧前腹腔注射NaHS (0 78mg·kg-1)。低氧结束后用右心导管法测定肺动脉压 ,测定右心室 /(左心室 +室间隔 ) [RV/ (LV +SP) ]比值 ,弹力纤维染色观察肺小动脉显微结构改变 ,透射电镜观察肺小动脉超微结构 ,酶促反应法测定肺动脉和肺组织中硫化氢合酶活性 ,定量RT PCR方法测定肺组织中胱硫醚 γ 裂解酶(CSE)基因表达水平。结果 :与对照组相比 ,低氧组大鼠平均肺动脉压升高 4 5 .6 % (P <0 .0 1) ,RV/ (LV +SP)比值增加 4 1% (P <0 .0 1) ;光镜下肺小动脉相对中膜厚度 (RMT)和相对中膜面积 (RMA)分别增加 4 1%和 39% (P <0 .0 1) ;电镜下肺小动脉内皮细胞增生 ,平滑肌细胞呈合成表型改变 ;硫化氢合酶活性在肺动脉和肺组织中分别降低 5 2 %和 5 4 % (P <0 .0 1) ,而且与平均肺动脉压均呈明显负相关 ;肺组织中硫化氢合酶基因表达水平下调 5 3%(P <0 .0 1)。与低氧组相比 ,低氧 +     

Establishment and characterization of chronic-hypoxia-resistant gastric cancer cell line MNK45/HYP

The chronic-hypoxia-resistant gastric cancer cell line was established,and its biological characteristics were explored and compared with the parental cell line.Gastric cancer cell lines were cultured under the degressive oxygen concentration.Cell doubling time was calculated by cell counting method.Chemo-resistance ability of cells was tested by MTT assay.Irradiation tolerance of cells was evaluated by colony forming method.Cell cycle distribution was tested with flow cytometry.Invasive ability was tested by Transwell method.The expression levels of GLUT-1 and HIF-1α were detected by using Western blot.MNK45/HYP cells successfully survived under the 1% concentration of oxygen and its cell doubling time was 35.01±1.02 h,while that of MNK45 was 27.35±0.83 h(P<0.01).The percentage of MNK45/HYP cells in G0/G1 stage was(58.3±6.1)%,and that of MNK45 cells was(42.2±6.0)%(P<0.05).Comparing with the parental cells MNK45,drug resistance indexes of 5-Fu,PTX,OXA,Sn38,GEM and VP16 in MNK45/HYP cells were respectively 5.3,1.3,3.6,2.2,4.8 and 4.4.Colony forming ability of MNK45/HYP cells after irradiation was also significantly higher than MNK45 cells.The invasive number of MNK45/HYP cells was 107.7±17.5,while that of MNK45 cells was 59.0±9.9.The expression levels of GLUT-1 and HIF-1α in MNK45/HYP cells were significantly higher than those in MNK45 cells.MNK45/HYP cells hold biological characteristics of hypoxia tumor with good tolerance to chronic hypoxia,and can be used for the research of solid tumor under chronic hypoxia condition.