The regulation of hypoxic response elements on the expression of vascular endothelial growth factor （VEGF） gene transfected to primary cultured rat skeletal myoblasts under hypoxic environment was investigated. pEGF...The regulation of hypoxic response elements on the expression of vascular endothelial growth factor （VEGF） gene transfected to primary cultured rat skeletal myoblasts under hypoxic environment was investigated. pEGFP-C3-9HRE-CMV-VEGF vector was constructed with molecular biology technique and transfected to primary cultured rat skeletal myoblasts by lipofectamine in vitro. Gene expression of transfected myoblasts was detected by RT-PCR, Western blot and fluorescence microscope under different oxygen concentrations and different hypoxia time. The results showed that in hypoxia group, the VEGF gene bands were seen and with the decrease of oxygen concentrations and prolongation of hypoxia time, the expression of VEGF mRNA was obviously increased. Under hypoxic environment, the expression of VEGF protein in the transfected myoblasts was significantly increased. EGFP was expressed only under hypoxic environment but not under normoxic environment. It was concluded that hypoxia promoter could be constructed with HRE and regulate the expression of VEGF gene under hypoxic and normoxic environment, which could enhance the re- liability of gene therapy.展开更多
Current clinical treatments cannot effectively delay the progression of osteoarthritis(OA).Consequently,joint replacement surgery is required for late-stage OA when patients cannot tolerate pain and joint dysfunction....Current clinical treatments cannot effectively delay the progression of osteoarthritis(OA).Consequently,joint replacement surgery is required for late-stage OA when patients cannot tolerate pain and joint dysfunction.Therefore,the prevention of OA progression in the early and middle stages is an urgent clinical problem.In a previous study,we demonstrated that NDRG3-mediated hypoxic response might be closely related to the development and progression of OA.In this study,an injectable thermosensitive hydrogel was established by cross-linking Pluronic F-127 and hyaluronic acid(HA)for the sustained release of hypoxia-induced exosomes(HExos)derived from adipose-derived mesenchymal stem cells.We demonstrated that for OA at the early and middle stages,the HExos-loaded HP hydrogel could maintain the chondrocyte phenotype by enhancing chondrocyte autophagy,reducing chondrocyte apoptosis,and promoting chondrocyte activity and proliferation through the NDRG3-mediated hypoxic response.This novel composite hydrogel,which could activate the NDRG3-mediated hypoxic response,may provide new ideas and a theoretical basis for the treatment of early-and mid-stage OA.展开更多
Cyanotic congenital heart disease(CCHD),a term describing the most severe congenital heart diseases are characterized by the anatomic malformation of a right to left shunt.Although the incidence of CCHD are far less t...Cyanotic congenital heart disease(CCHD),a term describing the most severe congenital heart diseases are characterized by the anatomic malformation of a right to left shunt.Although the incidence of CCHD are far less than the that of congenital heart diseases(CHD),patients with CCHD always present severe clinical features such as hypoxia,dyspnea,and heart failure.Chronic hypoxia induces hypoxemia that significantly contributes to poor prognosis in CCHD.Current studies have demonstrated that the prolyl-4-hydroxylase2(PHD2,encoded by EGLN1)/hypoxia-inducible factor-1A(HIF-1A)pathway is a key regulator of hypoxic response.Thus,we aim to assess the associations of single polymorphisms(SNPs)of the EGLN1 gene and hypoxic response in CCHD.A missense variant of EGLN1 c.380G>C(rs1209790)was found in 46 patients(46/126),with lower hypoxia incidence and higher rate of collateral vessel formation,compared with the wild type(P<0.05).In vitro experiments,during hypoxia,EGLN1 mutation reduced EGLN1 expression compared with the wild type,with higher HIF-1A,VEGF and EPO expression levels in the mutant.No difference in HK1 expression was observed between the mutant and wild type.CCHD patients with c.380G>C showed improved response to hypoxia compared with the wild-type counterparts.The EGLN1 c.380G>C mutation improves hypoxic response through the PHD2/HIF-1A pathway,which may provide a molecular mechanism for hypoxic response in CCHD.The effects of the EGLN1 c.380G>C mutation on CCHD prognosis deserve further investigation.展开更多
Two new ratiometric hypoxia probes(Ir-C343 and Ir-GFP)are synthesized by covalently incorporating florescent internal standard molecules coumarin 343(C343)and green fluorescent protein(GFP)into bis[1-(9,9-dimethyl-9H-...Two new ratiometric hypoxia probes(Ir-C343 and Ir-GFP)are synthesized by covalently incorporating florescent internal standard molecules coumarin 343(C343)and green fluorescent protein(GFP)into bis[1-(9,9-dimethyl-9H-fluoren-2-yl)-isoquinoline](succinylacetone)Ir(Ⅲ)(Ir-fliq),respectively.After connecting with internal standard molecules,the Ir-fliq moiety still exhibits high sensitivity to oxygen concentration,while the fluorescence intensity of the internal standard remains relatively constant under different oxygen concentrations.As a result,a ratiometric response is realized that is only related to oxygen concentration.In addition,Ir-GFP shows more promising applications in the ratiometric hypoxia imaging of cells due to its long excitation wavelength,good water solubility,high biocompatibility,and low relative fluorescence intensity compared with the phosphorescent emitter Ir-fliq.展开更多
To determine the effect of humoral factors and their interaction on the developement of acute hypoxic pulmonary pressor response (HPPR), we performed studies in 16 mongrel dogs. We measured plasma levels of noradreali...To determine the effect of humoral factors and their interaction on the developement of acute hypoxic pulmonary pressor response (HPPR), we performed studies in 16 mongrel dogs. We measured plasma levels of noradrealin (NE), angiotensin Ⅱ (AII), prostaglandin F2α (PGF2α), 6-keto-prostaglandin F1α (6KPGF1α), thromboxane B2 (TXB2), leukotriene B4 (LTB4) and 5-hydroxytryptamine (5-HT) before, during and after HPPR. Multiple regression analysis showed that the changes of pulmonary arterial systolic pressure (PASP) and pulmonary arterial diastolic pressure (PADP) correlated well with those of plasma concentration of NE, PGF2α and 6KPGF1α, respectively (r were equal to 0.633 and 0.668, respectively, P<0.01). The results of orthogonal experiment analysis with an injection of exogenous NE, PGF2α and PGIα into main pulmonary artery of dogs showed that NE and the interaction of PGF2α and PGI2α increased PASP (P<0.05) and PGI2 attenuated PASP (P<0.01). The interaction of PGF2α and PGI2 and of PGF2α and NE increased PADP(P<0.01) and PGI2 attenuated PADP (P<0.01).展开更多
基金a grant from National Natural Sciences Foundation of China (No. 30872542).
文摘The regulation of hypoxic response elements on the expression of vascular endothelial growth factor （VEGF） gene transfected to primary cultured rat skeletal myoblasts under hypoxic environment was investigated. pEGFP-C3-9HRE-CMV-VEGF vector was constructed with molecular biology technique and transfected to primary cultured rat skeletal myoblasts by lipofectamine in vitro. Gene expression of transfected myoblasts was detected by RT-PCR, Western blot and fluorescence microscope under different oxygen concentrations and different hypoxia time. The results showed that in hypoxia group, the VEGF gene bands were seen and with the decrease of oxygen concentrations and prolongation of hypoxia time, the expression of VEGF mRNA was obviously increased. Under hypoxic environment, the expression of VEGF protein in the transfected myoblasts was significantly increased. EGFP was expressed only under hypoxic environment but not under normoxic environment. It was concluded that hypoxia promoter could be constructed with HRE and regulate the expression of VEGF gene under hypoxic and normoxic environment, which could enhance the re- liability of gene therapy.
基金supported by the National Natural Science Foundation of China(Nos.81960404,81960401 and 82060308)Guizhou Province Science and Technology Project(Nos.[2019]1429 and[2019]2798)+2 种基金Guizhou Provincial People’s Hospital Doctoral Fund(No.GZSYBS[2019]01)Guizhou Provincial People’s Hospital Youth Fund(No.GZSYQN[2019]04)Guizhou Provincial Health Commission Science and Technology Fund(No.gzwkj2021-251).
文摘Current clinical treatments cannot effectively delay the progression of osteoarthritis(OA).Consequently,joint replacement surgery is required for late-stage OA when patients cannot tolerate pain and joint dysfunction.Therefore,the prevention of OA progression in the early and middle stages is an urgent clinical problem.In a previous study,we demonstrated that NDRG3-mediated hypoxic response might be closely related to the development and progression of OA.In this study,an injectable thermosensitive hydrogel was established by cross-linking Pluronic F-127 and hyaluronic acid(HA)for the sustained release of hypoxia-induced exosomes(HExos)derived from adipose-derived mesenchymal stem cells.We demonstrated that for OA at the early and middle stages,the HExos-loaded HP hydrogel could maintain the chondrocyte phenotype by enhancing chondrocyte autophagy,reducing chondrocyte apoptosis,and promoting chondrocyte activity and proliferation through the NDRG3-mediated hypoxic response.This novel composite hydrogel,which could activate the NDRG3-mediated hypoxic response,may provide new ideas and a theoretical basis for the treatment of early-and mid-stage OA.
基金This work is supported by the National Nature Science Foundation of China(81570218)Major Project of Chongqing Municipal Health Bureau(56-20141009)clinical project of Children’s Hospital of Chongqing Medical University(hjyn2012-6).
文摘Cyanotic congenital heart disease(CCHD),a term describing the most severe congenital heart diseases are characterized by the anatomic malformation of a right to left shunt.Although the incidence of CCHD are far less than the that of congenital heart diseases(CHD),patients with CCHD always present severe clinical features such as hypoxia,dyspnea,and heart failure.Chronic hypoxia induces hypoxemia that significantly contributes to poor prognosis in CCHD.Current studies have demonstrated that the prolyl-4-hydroxylase2(PHD2,encoded by EGLN1)/hypoxia-inducible factor-1A(HIF-1A)pathway is a key regulator of hypoxic response.Thus,we aim to assess the associations of single polymorphisms(SNPs)of the EGLN1 gene and hypoxic response in CCHD.A missense variant of EGLN1 c.380G>C(rs1209790)was found in 46 patients(46/126),with lower hypoxia incidence and higher rate of collateral vessel formation,compared with the wild type(P<0.05).In vitro experiments,during hypoxia,EGLN1 mutation reduced EGLN1 expression compared with the wild type,with higher HIF-1A,VEGF and EPO expression levels in the mutant.No difference in HK1 expression was observed between the mutant and wild type.CCHD patients with c.380G>C showed improved response to hypoxia compared with the wild-type counterparts.The EGLN1 c.380G>C mutation improves hypoxic response through the PHD2/HIF-1A pathway,which may provide a molecular mechanism for hypoxic response in CCHD.The effects of the EGLN1 c.380G>C mutation on CCHD prognosis deserve further investigation.
基金financially supported by the National Key R&D Program of China(Nos.2017YFA0701301 and 2017YFA0205400)the National Natural Science Foundation of China(Nos.92163214,51690153,21720102005 and 51803089)the Natural Science Foundation of Jiangsu Province(No.BK20202002)。
文摘Two new ratiometric hypoxia probes(Ir-C343 and Ir-GFP)are synthesized by covalently incorporating florescent internal standard molecules coumarin 343(C343)and green fluorescent protein(GFP)into bis[1-(9,9-dimethyl-9H-fluoren-2-yl)-isoquinoline](succinylacetone)Ir(Ⅲ)(Ir-fliq),respectively.After connecting with internal standard molecules,the Ir-fliq moiety still exhibits high sensitivity to oxygen concentration,while the fluorescence intensity of the internal standard remains relatively constant under different oxygen concentrations.As a result,a ratiometric response is realized that is only related to oxygen concentration.In addition,Ir-GFP shows more promising applications in the ratiometric hypoxia imaging of cells due to its long excitation wavelength,good water solubility,high biocompatibility,and low relative fluorescence intensity compared with the phosphorescent emitter Ir-fliq.
文摘To determine the effect of humoral factors and their interaction on the developement of acute hypoxic pulmonary pressor response (HPPR), we performed studies in 16 mongrel dogs. We measured plasma levels of noradrealin (NE), angiotensin Ⅱ (AII), prostaglandin F2α (PGF2α), 6-keto-prostaglandin F1α (6KPGF1α), thromboxane B2 (TXB2), leukotriene B4 (LTB4) and 5-hydroxytryptamine (5-HT) before, during and after HPPR. Multiple regression analysis showed that the changes of pulmonary arterial systolic pressure (PASP) and pulmonary arterial diastolic pressure (PADP) correlated well with those of plasma concentration of NE, PGF2α and 6KPGF1α, respectively (r were equal to 0.633 and 0.668, respectively, P<0.01). The results of orthogonal experiment analysis with an injection of exogenous NE, PGF2α and PGIα into main pulmonary artery of dogs showed that NE and the interaction of PGF2α and PGI2α increased PASP (P<0.05) and PGI2 attenuated PASP (P<0.01). The interaction of PGF2α and PGI2 and of PGF2α and NE increased PADP(P<0.01) and PGI2 attenuated PADP (P<0.01).
