AIM:To examine the relevance of hypoxia inducible factor(HIF-1)and nitric oxide(NO)on the preservation of fatty liver against cold ischemia-reperfusion injury(IRI). METHODS:We used an isolated perfused rat liver model...AIM:To examine the relevance of hypoxia inducible factor(HIF-1)and nitric oxide(NO)on the preservation of fatty liver against cold ischemia-reperfusion injury(IRI). METHODS:We used an isolated perfused rat liver model and we evaluated HIF-1αin steatotic and non-steatotic livers preserved for 24 h at 4℃in University of Wisconsin and IGL-1 solutions,and then subjected to 2 h of normothermic reperfusion.After normoxic reperfusion,liver enzymes,bile production,bromosulfophthalein clearance,as well as HIF-1αand NO[endothelial NO synthase(eNOS)activity and nitrites/nitrates]were also measured.Other factors associated with the higher susceptibility of steatotic livers to IRI,such as mitochondrial damage and vascular resistance were evaluated. RESULTS:A significant increase in HIF-1αwas found in steatotic and non-steatotic livers preserved in IGL-1 after cold storage.Livers preserved in IGL-1 showed a significant attenuation of liver injury and improvement in liver function parameters.These benefits were enhanced by the addition of trimetazidine(an antiischemic drug),which induces NO and eNOS activation, to IGL-1 solution.In normoxic reperfusion,the presence of NO favors HIF-1αaccumulation,promoting also the activation of other cytoprotective genes,such as hemeoxygenase-1. CONCLUSION:We found evidence for the role of the HIF-1α/NO system in fatty liver preservation,especially when IGL-1 solution is used.展开更多
BACKGROUND Glycolysis caused by hypoxia-induced abnormal activation of hypoxia inducible factor-1α(HIF-1α)in the immune microenvironment promotes the progression of hepatocellular carcinoma(HCC),leading to enhanced ...BACKGROUND Glycolysis caused by hypoxia-induced abnormal activation of hypoxia inducible factor-1α(HIF-1α)in the immune microenvironment promotes the progression of hepatocellular carcinoma(HCC),leading to enhanced drug resistance in cancer cells.Therefore,altering the immunosuppressive microenvironment by improving the hypoxic state is a new goal in improving cancer treatment.AIM To analyse the role of HIF-1α,which is closely related to tumour proliferation,invasion,metastasis,and angiogenesis,in the proliferation and invasion of liver cancer,and to explore the HIF-1αpathway-mediated anti-cancer mechanism of sirolimus(SRL)combined with Huai Er.METHODS Previous studies on HCC tissues identified the importance of HIF-1α,glucose transporter 1(GLUT1),and lactate dehydrogenase A(LDHA)expression.In this study,HepG2 and Huh7 cell lines were treated,under hypoxic and normoxic conditions,with a combination of SRL and Huai Er.The effects on proliferation,invasion,cell cycle,and apoptosis were analysed.Proteomics and genomics techniques were used to analyze the HIF-1α-related signalling pathway during SRL combined with Huai Er treatment and its inhibition of the proliferation of HCC cells.RESULTS High levels of HIF-1α,LDHA,and GLUT-1 were found in poorly differentiated HCC,with lower patient survival rates.Hypoxia promoted the proliferation of HepG2 and Huh7 cells and weakened the apoptosis and cell cycle blocking effects of the SRL/Huai Er treatment.This was achieved by activation of HIF-1αand glycolysis in HCC,leading to the upregulation of LDHA,GLUT-1,Akt/mammalian target of rapamycin(mTOR),vascular endothelial growth factor(VEGF),and Forkhead box P3 and downregulation of phosphatase and tensin homolog deleted on chromosome ten(PTEN)and p27.The hypoxia-induced activation of HIF-1αshowed the greatest attenuation in the SRL/Huai Er(S50+H8)group compared to the drug treatments alone(P<0.001).The S50+H8 treatment significantly downregulated the expression of mTOR and HIF-1α,and significantly reduced the expression of VEGF mRNA.Meanwhile,the combined blocking of mTOR and HIF-1αenhanced the downregulation of Akt/mTOR,HIF-1α,LDHA,and GLUT-1 mRNA and resulted in the downregulation of PTEN,p27,and VEGF mRNA(P<0.001).CONCLUSION SRL increases the anti-cancer effect of Huai Er,which reduces the promotion of hypoxia-induced HIF-1αon the Warburg effect by inhibition of the PI3K/Akt/mTOR-HIF-1αand HIF-1α-PTEN signalling pathways in HCC.展开更多
As a common clinical disease, fracture is often accompanied by pain, swelling, bleeding as well as other symptoms and has a high disability rate, even threatening life, seriously endangering patients’ physical and ps...As a common clinical disease, fracture is often accompanied by pain, swelling, bleeding as well as other symptoms and has a high disability rate, even threatening life, seriously endangering patients’ physical and psychological health and quality of life. Medical practitioners take many strategies for the treatment of fracture healing, including Traditional Chinese Medicine(TCM). In the early stage of fracture healing,the local fracture is often in a state of hypoxia, accompanied by the expression of hypoxia inducible factor-1α(HIF-1α), which is beneficial to wound healing. Through literature mining, we thought that hypoxia, HIF-1α and downstream factors affected the mechanism of fracture healing, as well as dominated this process. Therefore, we reviewed the local characteristics and related signaling pathways involved in the fracture healing process and summarized the intervention of TCM on these mechanisms,in order to inspirit the new strategy for fracture healing, as well as elaborate on the possible principles of TCM in treating fractures based on the HIF molecular mechanism.展开更多
Mild traumatic brain injury(TBI), also called concussion, initiates sequelae leading to motor deficits, cognitive impairments and subtly compromised neurobehaviors. While the acute phase of TBI is associated with neur...Mild traumatic brain injury(TBI), also called concussion, initiates sequelae leading to motor deficits, cognitive impairments and subtly compromised neurobehaviors. While the acute phase of TBI is associated with neuroinflammation and nitroxidative burst, the chronic phase shows a lack of stimulation of the neurorepair process and regeneration. The deficiency of nitric oxide(NO), the consequent disturbed NO metabolome, and imbalanced mechanisms of S-nitrosylation are implicated in blocking the mechanisms of neurorepair processes and functional recovery in the both phases. Hypoxia inducible factor-1 alpha(HIF-1α), a master regulator of hypoxia/ischemia, stimulates the process of neurorepair and thus aids in functional recovery after brain trauma. The activity of HIF-1α is regulated by NO via the mechanism of S-nitrosylation of HIF-1α. S-nitrosylation is dynamically regulated by NO metabolites such as S-nitrosoglutathione(GSNO) and peroxynitrite. GSNO stabilizes, and peroxynitrite destabilizes HIF-1α. Exogenously administered GSNO was found not only to stabilize HIF-1α and to induce HIF-1α-dependent genes but also to stimulate the regeneration process and to aid in functional recovery in TBI animals.展开更多
BACKGROUND: Hypoxia inducible factor-1 alpha (HIF-1 α) and erythropoietin(EPO), possessing neuroprotective effect in the cerebral ischemia, might play an important role in the formation of cerebral ischemic tolerance...BACKGROUND: Hypoxia inducible factor-1 alpha (HIF-1 α) and erythropoietin(EPO), possessing neuroprotective effect in the cerebral ischemia, might play an important role in the formation of cerebral ischemic tolerance (IT). OBJECTIVE:To observe the neuroprotective effect of cerebral ischemic preconditioning(IPC) of rats, and the expression and mechanism of HIF-1α and target gene erythropoietin in the brain tissue following the formation of cerebral IT. DESIGN:A randomized and controlled observation. SETTING: Department of Neurology, the Affiliated Hospital of Medical College, Qingdao University. MATERIALS: Totally 84 enrolled adult healthy male Wistar rats of clean grade, weighing 250 to 300 g, were provided by the Animal Experimental Department, Tongji Medical College of Huazhong University of Science and Technology. Ready-to-use SABC reagent kit and rabbit anti-rat HIF-1α monoclonal antibody were purchased from Boshide Bioengineering Co.Ltd (Wuhan); Rabbit anti-rat EPO monoclonal antibody was purchased from Santa Cruz Company (USA). METHODS: This experiment was carried out in the Department of Anatomy, Medical College, Qingdao University during March 2005 to March 2006. ① The 84 rats were divided into 3 groups by a lot: IPC group (n=40), sham-operation group (n=40) and control group (n=4). In the IPC group, middle cerebral artery was occluded for 2 hours respectively on the 1st, 3rd, 7th, 14th and 21st days of the reperfusion following 10-minute preischemia was made using a modified middle cerebral artery second suture method from Zea-Longa. The rats were sacrificed 22 hours after reperfusion in the end of middle cerebral artery occlusion (MCAO). That was to say, after 10-minute preischemia, suture was exited to the external carotid artery and embedded subcutaneously. Middle cerebral artery was occluded again to form the second reperfusion at the set time point after reperfusion. Twenty-two hours later, rats were sacrificed; In the sham-operation group,the preischemia was substituted by sham-operation(only common carotid artery and crotch were exposed, and MCAO by suture was omitted), and the other procedures were the same as those in the IPC group. In the control group, rats were given sham-operation twice at an interval of one day, and they were sacrificed 24 hours after the second sham-operation. ② Brain tissue was taken from the rats in each group. Cerebral infarction area of each layer was measured with TTC staining, and total cerebral infarction volume (The total cerebral infarction area of each layer×interspace ) was calculated. After brain tissue was stained by haematoxylin-esoin (HE), the form of nerve cells was observed under an optical microscope, and the expressions of HIF-1αand EPO protein in the brain tissue were detected with immunohistochemical method. MAIN OUTCOME MEASURES: ①Cerebral infarction volume;②form of nerve cell; ③ the expression of HIF-1α and EPO protein in the brain tissue. RESULTS:Totally 84 rats were enrolled in the experiment. The dead rats were randomly supplied during the experiment, and finally 84 rats entered the stage of result analysis. ① Detection of cerebral infarction volume of rats in each group: Cerebral infarction volume in the IPC group was significantly smaller than that in the sham-operation group on the 1st, 3rd and 7th days after reperfusion respectively [(161.2±6.9) mm3 vs (219.9±11.2) mm3, (134.9±9.0) mm3 vs (218.6±13.0) mm3, (142.9±13.7) mm3 vs (221.3±14.2) mm3, t=8.924,10.587,7.947, P < 0.01]. ② Observation of nerve cell form of brain tissue: HE staining showed that the ischemic degree, range and cerebral edema degree of IPC group were significantly milder than those of sham-operation group. ③ The expressions of HIF-1α and EPO protein in cerebral cortex and hippocampus : The expression of HIF-1αof IPC group was significantly higher than that of sham-operation group on the 1st, 3rd and 7th days after reperfusion respectively (125.93±3.79 vs 117.65±5.60, 140.63±4.64 vs 119.33±4.26, 131.15±2.74 vs 107.60±3.89, t=2.449, 6.763,9.899,P < 0.05-0.01). The expression of EPO of IPC group was significantly higher than that of sham-operation group on the 3rd and 7th days after perfusion respectively (141.68±3.29 vs 126.33±4.51, 138.88±2.59 vs 125.58±6.18,t=5.499,3.970, P < 0.05). CONCLUSION: ① IPC can protect the never cells in rat brain and the best time to onset of cerebral IT induced by IPC is 1 to 7 days after reperfusion. ② Neuroprotective effect of cerebral IT might be related to the expression of HIF-1α and its target gene EPO.展开更多
Inhibiting retinal neovascularization is the optimal strategy for the treatment of retina-related diseases, but there is currently no effective treatment for retinal neovascularization. P-element-induced wimpy testis(...Inhibiting retinal neovascularization is the optimal strategy for the treatment of retina-related diseases, but there is currently no effective treatment for retinal neovascularization. P-element-induced wimpy testis(PIWI)-interacting RNA(piRNA) is a type of small non-coding RNA implicated in a variety of diseases. In this study, we found that the expression of piR-1245 and the interacting protein PIWIL2 were remarkably increased in human retinal endothelial cells cultured in a hypoxic environment, and cell apoptosis, migration, tube formation and proliferation were remarkably enhanced in these cells. Knocking down piR-1245 inhibited the above phenomena. After intervention by a p-JAK2 activator, piR-1245 decreased the expression of hypoxia inducible factor-1α and vascular endothelial growth factor through the JAK2/STAT3 pathway. For in vivo analysis, 7-day-old newborn mice were raised in 75 ± 2% hyperoxia for 5 days and then piR-1245 in the retina was knocked down. In these mice, the number of newly formed vessels in the retina was decreased, the expressions of inflammationrelated proteins were reduced, the number of apoptotic cells in the retina was decreased, the JAK2/STAT3 pathway was inhibited, and the expressions of hypoxia inducible factor-1α and vascular endothelial growth factor were decreased. Injection of the JAK2 inhibitor JAK2/TYK2-IN-1 into the vitreous cavity inhibited retinal neovascularization in mice and reduced expression of hypoxia inducible factor-1α and vascular endothelial growth factor. These findings suggest that piR-1245 activates the JAK2/STAT3 pathway, regulates the expression of hypoxia inducible factor-1α and vascular endothelial growth factor, and promotes retinal neovascularization. Therefore, piR-1245 may be a new therapeutic target for retinal neovascularization.展开更多
The mortality of patients with severe pneumonia caused by H1N1 infection is closely related to viral replication and cytokine storm.However,the specific mechanisms triggering virus replication and cytokine storm are s...The mortality of patients with severe pneumonia caused by H1N1 infection is closely related to viral replication and cytokine storm.However,the specific mechanisms triggering virus replication and cytokine storm are still not fully elucidated.Here,we identified hypoxia inducible factor-1α(HIF-1α)as one of the major host molecules that facilitates H1N1 virus replication followed by cytokine storm in alveolar epithelial cells.Specifically,HIF-1αprotein expression is upregulated after H1N1 infection.Deficiency of HIF-1αattenuates pulmonary injury,viral replication and cytokine storm in vivo.In addition,viral replication and cytokine storm were inhibited after HIF-1αknockdown in vitro.Mechanistically,the invasion of H1N1 virus into alveolar epithelial cells leads to a shift in glucose metabolism to glycolysis,with rapid production of ATP and lactate.Inhibition of glycolysis significantly suppresses viral replication and inflammatory responses.Further analysis revealed that H1N1-induced HIF-1αcan promote the expression of hexokinase 2(HK2),the key enzyme of glycolysis,and then not only provide energy for the rapid replication of H1N1 virus but also produce lactate,which reduces the accumulation of the MAVS/RIG-I complex and inhibits IFN-α/βproduction.In conclusion,this study demonstrated that the upregulation of HIF-1αby H1N1 infection augments viral replication and cytokine storm by cellular metabolic reprogramming toward glycolysis mainly through upregulation of HK2,providing a theoretical basis for finding potential targets for the treatment of severe pneumonia caused by H1N1 infection.展开更多
OBJECTIVEα-Hederin is an effective component of the traditional Chinese medicine Pulsatilla chinensis,which has been reported to exert many pharmacological activities.However,the effect ofα-hederin on metabolism is ...OBJECTIVEα-Hederin is an effective component of the traditional Chinese medicine Pulsatilla chinensis,which has been reported to exert many pharmacological activities.However,the effect ofα-hederin on metabolism is still unclear.This study aimed to illuminate the role ofα-hederin in glucose metabolism in lung cancer cells and investigate the molecular mechanism ofα-hederin.METHODS CCK8 and colony formation assays were employed to assess the anti-proliferative effects induced byα-hederin.Glucose uptake,ATP generation,and reduced lactate production were measured using kits,and an A549 tumor xenograft mouse model of lung cancer was used to assess the in vivo antitumor effect ofα-hederin(5,10 mg·kg^-1).Glycolytic-related key enzymes were detected by Western blotting and immunohisto⁃chemical staining.RESULTS Cell proliferation was significantly inhibited byα-hederin in a dose-dependent manner and thatα-hederin inhibited glucose uptake and ATP generation and reduced lactate production.Furthermore,α-hederin remarkably inhibited hexokinase 2(HK2),glucose transporters 1(GLUT1),pyruvate kinase M2(PKM2),lactate dehydro⁃genase A(LDHA),monocarboxylate transporter(MCT4),c-Myc,and hypoxia inducible factor-1α(HIF-1α)protein expres⁃sion.Using inhibitors,we proved thatα-hederin inhibits glycolysis by inhibiting glycolytic regulators.Moreover,a tumor xenograft mouse model of lung cancer further confirmed thatα-hederin inhibits lung cancer growth via inhibiting glycolysis in vivo.CONCLUSIONα-Hederin inhibits the growth of non-small cell lung cancer A549 cells by inhibiting glycolysis.The mechanism of glycolysis inhibition includesα-hederin inhibiting the expression of the glycolytic regulatory factors HIF-1α and c-Myc.展开更多
Objective To observe the expression of hypoxia inducible factor-1α (HIF-1α) in the retina of rabbits with acute high intraocular pressure and to investigate the mechanism of systemic domestic recombinant human eryth...Objective To observe the expression of hypoxia inducible factor-1α (HIF-1α) in the retina of rabbits with acute high intraocular pressure and to investigate the mechanism of systemic domestic recombinant human erythropoietin (rhEPO) protecting the retina from ischemia-reperfusion injury. Methods First,control group and model group were established in rabbit eyes. The acute high intraocular pressure model was established by saline perfusion into anterior chamber,and then hypodermic injection of domestic rhEPO was made. HIF-1α protein in the retina was observed by immunohistochemical staining method on days 1,3,7 and 14 after retinal ischemia-reperfusion,respectively. Results No cells with HIF-1α positive expression were observed in the retina of the control group. Cells with HIF-1α positive expression in the model group outnumbered those in the control group (P<0.01). The resemblance pattern occurred in EPO group but its degree was slightly greater than that in the model group from day 3 after ischemia-reperfusion (P<0.05). Conclusion Domestic rhEPO can down-regulate the expression of HIF-1α in the retina with acute high intraocular pressure,which may be one of the mechanisms that rhEPO protects the retina from ischemia-reperfusion injury.展开更多
Metabolic reprogramming is a common phenomenon in cancer,with aerobic glycolysis being one of its important characteristics.Hypoxia-inducible factor-1α(HIF1Α)is thought to play an important role in aerobic glycolysi...Metabolic reprogramming is a common phenomenon in cancer,with aerobic glycolysis being one of its important characteristics.Hypoxia-inducible factor-1α(HIF1Α)is thought to play an important role in aerobic glycolysis.Meanwhile,naringin is a natural flavanone glycoside derived from grapefruits and many other citrus fruits.In this work,we identified glycolytic genes related to HIF1Αby analyzing the colon cancer database.The analysis of extracellular acidification rate and cell function verified the regulatory effects of HIF1Αoverexpression on glycolysis,and the proliferation and migration of colon cancer cells.Moreover,naringin was used as an inhibitor of colon cancer cells to illustrate its effect on HIF1Αfunction.The results showed that the HIF1Αand enolase 2(ENO2)levels in colon cancer tissues were highly correlated,and their high expression indicated a poor prognosis for colon cancer patients.Mechanistically,HIF1Αdirectly binds to the DNA promoter region and upregulates the transcription of ENO2;ectopic expression of ENO2 increased aerobic glycolysis in colon cancer cells.Most importantly,we found that the appropriate concentration of naringin inhibited the transcriptional activity of HIF1Α,which in turn decreased aerobic glycolysis in colon cancer cells.Generally,naringin reduces glycolysis in colon cancer cells by reducing the transcriptional activity of HIF1Αand the proliferation and invasion of colon cancer cells.This study helps to elucidate the relationship between colon cancer progression and glucose metabolism,and demonstrates the efficacy of naringin in the treatment of colon cancer.展开更多
AIM:To examine changes in retinal vasculature after treatment with different oxygen concentrations from common retinopathy of prematurity(ROP) models and to determine a novel and practical ROP model.METHODS:A sample o...AIM:To examine changes in retinal vasculature after treatment with different oxygen concentrations from common retinopathy of prematurity(ROP) models and to determine a novel and practical ROP model.METHODS:A sample of 14 newborn Sprague-Dawley rats was used.The study group(n=7) was exposed to95%oxygen for 4h per day followed by normoxic laboratory conditions for 20 h.This cycle was repeated for 14 d.The control group(n=7) was subjected to normobaric normoxic conditions.On postnatal day 14(P14),the two groups were placed in room air for 7d.On P21,the two groups were examined using indirect ophthalmoscopy.All eyes were enucleated for immunofluorescence(IF) staining of the vasculature of retinas and analysis of vascular endothelial growth factor(VEGF),hypoxia inducible factor-1 alpha(HIF-1α),placental growth factor(PLGF) in vitreous humor,and then the rats were sacrificed by decapitation.All procedures were repeated using another litter of 14 pups.RESULTS:In the study group and under normobaric hyperoxic conditions,retinal neovascularization and peripheral avascular retina were determined in 85%of the rats through indirect ophthalmoscopic examination.Also IF staining of retina of the study group showed retarded peripheral vascular growth.The difference between the two groups for VEGF,HIF-1α and PLGF concentrations of vitreous humor was statistically significant(P=0.003,0.007,0.027 respectively).CONCLUSION:Fluctuating oxygen concentrations are primarily responsible for retinal neovascularization.Our new ROP model is practical and applicable for all retinal neovascularization studies,considering the laboratory procedures.展开更多
Background:Traumatic brain edema(TBE)is caused by a specific water channel mediated by membrane aquaporins.Aquaporin-4(AQP4)plays an especially important role in this process,but the relationship between AQP4 and TBE ...Background:Traumatic brain edema(TBE)is caused by a specific water channel mediated by membrane aquaporins.Aquaporin-4(AQP4)plays an especially important role in this process,but the relationship between AQP4 and TBE remains unclear.The purpose of this study was to explore expression of AQP4 in the hippocampus after traumatic brain injury(TBI),as well as the effect of brain edema on skeletal protein and its function in hippocampal neurons.Methods:The adult male Wistar rats we divided into a sham group and a TBI group,the latter of which was further divided into 1,3,6,12,24 and 72 hours(h)and 15 days(d)post injury subgroups.A proper TBI model was established,and brain edema was assessed in each group by water content.We measured the abundance of various proteins,including hypoxia inducible factor-1α(HIF-1α),AQP4,microtubule-associated protein 2(MAP2),tau-5 protein,phosphorylated level of TAU,synaptophysin,cyclic adenosine monophosphate response element binding protein(CREB),phosphorylated CREB and general control nonrepressed 2,in each group.Hippocampal neurons and spatial memory test were analyzed in different time points.Results:Compared with that in the sham group,the level of AQP4 in hippocampal neurons began to significantly increase at 1 h post TBI and then decreased at 15 d post TBI.During this time frame,AQP4 level peaked at 12 and 72 h,and these peaks were closely correlated with high brain water content.HIF-1αdisplayed a similar trend.Conversely,levels of MAP2 began to decrease at 1 h post TBI and then increase at 15 d post TBI.In addition,the most severe brain edema in rats was found at 24 h post TBI,with neuronal loss and hippocampal dendritic spine injury.Compared to those in the sham group,rats in the TBI groups had significantly prolonged latency and significantly shortened exploration time.Conclusions:AQP4 level was closely correlated with severity of brain edema,and abnormal levels thereof aggravated such severity after TBI.展开更多
基金Supported by The Ministerio de de Sanidad y Consumo(PI081988)CIBER-EHD,Instituto Carlos Ⅲ,Madrid and Ministerio de Asuntos Exteriores y de Cooperación Internacionales(A/020255/08 and A/02987/09),Madrid
文摘AIM:To examine the relevance of hypoxia inducible factor(HIF-1)and nitric oxide(NO)on the preservation of fatty liver against cold ischemia-reperfusion injury(IRI). METHODS:We used an isolated perfused rat liver model and we evaluated HIF-1αin steatotic and non-steatotic livers preserved for 24 h at 4℃in University of Wisconsin and IGL-1 solutions,and then subjected to 2 h of normothermic reperfusion.After normoxic reperfusion,liver enzymes,bile production,bromosulfophthalein clearance,as well as HIF-1αand NO[endothelial NO synthase(eNOS)activity and nitrites/nitrates]were also measured.Other factors associated with the higher susceptibility of steatotic livers to IRI,such as mitochondrial damage and vascular resistance were evaluated. RESULTS:A significant increase in HIF-1αwas found in steatotic and non-steatotic livers preserved in IGL-1 after cold storage.Livers preserved in IGL-1 showed a significant attenuation of liver injury and improvement in liver function parameters.These benefits were enhanced by the addition of trimetazidine(an antiischemic drug),which induces NO and eNOS activation, to IGL-1 solution.In normoxic reperfusion,the presence of NO favors HIF-1αaccumulation,promoting also the activation of other cytoprotective genes,such as hemeoxygenase-1. CONCLUSION:We found evidence for the role of the HIF-1α/NO system in fatty liver preservation,especially when IGL-1 solution is used.
基金Supported by the Natural Science Foundation of Capital Medical University,No.PYZ20014 and No.PYZ21074。
文摘BACKGROUND Glycolysis caused by hypoxia-induced abnormal activation of hypoxia inducible factor-1α(HIF-1α)in the immune microenvironment promotes the progression of hepatocellular carcinoma(HCC),leading to enhanced drug resistance in cancer cells.Therefore,altering the immunosuppressive microenvironment by improving the hypoxic state is a new goal in improving cancer treatment.AIM To analyse the role of HIF-1α,which is closely related to tumour proliferation,invasion,metastasis,and angiogenesis,in the proliferation and invasion of liver cancer,and to explore the HIF-1αpathway-mediated anti-cancer mechanism of sirolimus(SRL)combined with Huai Er.METHODS Previous studies on HCC tissues identified the importance of HIF-1α,glucose transporter 1(GLUT1),and lactate dehydrogenase A(LDHA)expression.In this study,HepG2 and Huh7 cell lines were treated,under hypoxic and normoxic conditions,with a combination of SRL and Huai Er.The effects on proliferation,invasion,cell cycle,and apoptosis were analysed.Proteomics and genomics techniques were used to analyze the HIF-1α-related signalling pathway during SRL combined with Huai Er treatment and its inhibition of the proliferation of HCC cells.RESULTS High levels of HIF-1α,LDHA,and GLUT-1 were found in poorly differentiated HCC,with lower patient survival rates.Hypoxia promoted the proliferation of HepG2 and Huh7 cells and weakened the apoptosis and cell cycle blocking effects of the SRL/Huai Er treatment.This was achieved by activation of HIF-1αand glycolysis in HCC,leading to the upregulation of LDHA,GLUT-1,Akt/mammalian target of rapamycin(mTOR),vascular endothelial growth factor(VEGF),and Forkhead box P3 and downregulation of phosphatase and tensin homolog deleted on chromosome ten(PTEN)and p27.The hypoxia-induced activation of HIF-1αshowed the greatest attenuation in the SRL/Huai Er(S50+H8)group compared to the drug treatments alone(P<0.001).The S50+H8 treatment significantly downregulated the expression of mTOR and HIF-1α,and significantly reduced the expression of VEGF mRNA.Meanwhile,the combined blocking of mTOR and HIF-1αenhanced the downregulation of Akt/mTOR,HIF-1α,LDHA,and GLUT-1 mRNA and resulted in the downregulation of PTEN,p27,and VEGF mRNA(P<0.001).CONCLUSION SRL increases the anti-cancer effect of Huai Er,which reduces the promotion of hypoxia-induced HIF-1αon the Warburg effect by inhibition of the PI3K/Akt/mTOR-HIF-1αand HIF-1α-PTEN signalling pathways in HCC.
基金This work is financially supported by National Natural Science Foundation of China(No.82060877,82104527)the Science and Technology Planning Project of Tibet Autonomous Region(No.XZ202101ZD 0022G)Fundamental Research Funds for the Central Universities(No.lzujbky-2022-ct03).
文摘As a common clinical disease, fracture is often accompanied by pain, swelling, bleeding as well as other symptoms and has a high disability rate, even threatening life, seriously endangering patients’ physical and psychological health and quality of life. Medical practitioners take many strategies for the treatment of fracture healing, including Traditional Chinese Medicine(TCM). In the early stage of fracture healing,the local fracture is often in a state of hypoxia, accompanied by the expression of hypoxia inducible factor-1α(HIF-1α), which is beneficial to wound healing. Through literature mining, we thought that hypoxia, HIF-1α and downstream factors affected the mechanism of fracture healing, as well as dominated this process. Therefore, we reviewed the local characteristics and related signaling pathways involved in the fracture healing process and summarized the intervention of TCM on these mechanisms,in order to inspirit the new strategy for fracture healing, as well as elaborate on the possible principles of TCM in treating fractures based on the HIF molecular mechanism.
基金supported by grants from VA merit awards(BX3401 and RX2090)
文摘Mild traumatic brain injury(TBI), also called concussion, initiates sequelae leading to motor deficits, cognitive impairments and subtly compromised neurobehaviors. While the acute phase of TBI is associated with neuroinflammation and nitroxidative burst, the chronic phase shows a lack of stimulation of the neurorepair process and regeneration. The deficiency of nitric oxide(NO), the consequent disturbed NO metabolome, and imbalanced mechanisms of S-nitrosylation are implicated in blocking the mechanisms of neurorepair processes and functional recovery in the both phases. Hypoxia inducible factor-1 alpha(HIF-1α), a master regulator of hypoxia/ischemia, stimulates the process of neurorepair and thus aids in functional recovery after brain trauma. The activity of HIF-1α is regulated by NO via the mechanism of S-nitrosylation of HIF-1α. S-nitrosylation is dynamically regulated by NO metabolites such as S-nitrosoglutathione(GSNO) and peroxynitrite. GSNO stabilizes, and peroxynitrite destabilizes HIF-1α. Exogenously administered GSNO was found not only to stabilize HIF-1α and to induce HIF-1α-dependent genes but also to stimulate the regeneration process and to aid in functional recovery in TBI animals.
基金the Scientific andTechnological DevelopmentProgram of Qingdao City, No.No.05-1-NS-73
文摘BACKGROUND: Hypoxia inducible factor-1 alpha (HIF-1 α) and erythropoietin(EPO), possessing neuroprotective effect in the cerebral ischemia, might play an important role in the formation of cerebral ischemic tolerance (IT). OBJECTIVE:To observe the neuroprotective effect of cerebral ischemic preconditioning(IPC) of rats, and the expression and mechanism of HIF-1α and target gene erythropoietin in the brain tissue following the formation of cerebral IT. DESIGN:A randomized and controlled observation. SETTING: Department of Neurology, the Affiliated Hospital of Medical College, Qingdao University. MATERIALS: Totally 84 enrolled adult healthy male Wistar rats of clean grade, weighing 250 to 300 g, were provided by the Animal Experimental Department, Tongji Medical College of Huazhong University of Science and Technology. Ready-to-use SABC reagent kit and rabbit anti-rat HIF-1α monoclonal antibody were purchased from Boshide Bioengineering Co.Ltd (Wuhan); Rabbit anti-rat EPO monoclonal antibody was purchased from Santa Cruz Company (USA). METHODS: This experiment was carried out in the Department of Anatomy, Medical College, Qingdao University during March 2005 to March 2006. ① The 84 rats were divided into 3 groups by a lot: IPC group (n=40), sham-operation group (n=40) and control group (n=4). In the IPC group, middle cerebral artery was occluded for 2 hours respectively on the 1st, 3rd, 7th, 14th and 21st days of the reperfusion following 10-minute preischemia was made using a modified middle cerebral artery second suture method from Zea-Longa. The rats were sacrificed 22 hours after reperfusion in the end of middle cerebral artery occlusion (MCAO). That was to say, after 10-minute preischemia, suture was exited to the external carotid artery and embedded subcutaneously. Middle cerebral artery was occluded again to form the second reperfusion at the set time point after reperfusion. Twenty-two hours later, rats were sacrificed; In the sham-operation group,the preischemia was substituted by sham-operation(only common carotid artery and crotch were exposed, and MCAO by suture was omitted), and the other procedures were the same as those in the IPC group. In the control group, rats were given sham-operation twice at an interval of one day, and they were sacrificed 24 hours after the second sham-operation. ② Brain tissue was taken from the rats in each group. Cerebral infarction area of each layer was measured with TTC staining, and total cerebral infarction volume (The total cerebral infarction area of each layer×interspace ) was calculated. After brain tissue was stained by haematoxylin-esoin (HE), the form of nerve cells was observed under an optical microscope, and the expressions of HIF-1αand EPO protein in the brain tissue were detected with immunohistochemical method. MAIN OUTCOME MEASURES: ①Cerebral infarction volume;②form of nerve cell; ③ the expression of HIF-1α and EPO protein in the brain tissue. RESULTS:Totally 84 rats were enrolled in the experiment. The dead rats were randomly supplied during the experiment, and finally 84 rats entered the stage of result analysis. ① Detection of cerebral infarction volume of rats in each group: Cerebral infarction volume in the IPC group was significantly smaller than that in the sham-operation group on the 1st, 3rd and 7th days after reperfusion respectively [(161.2±6.9) mm3 vs (219.9±11.2) mm3, (134.9±9.0) mm3 vs (218.6±13.0) mm3, (142.9±13.7) mm3 vs (221.3±14.2) mm3, t=8.924,10.587,7.947, P < 0.01]. ② Observation of nerve cell form of brain tissue: HE staining showed that the ischemic degree, range and cerebral edema degree of IPC group were significantly milder than those of sham-operation group. ③ The expressions of HIF-1α and EPO protein in cerebral cortex and hippocampus : The expression of HIF-1αof IPC group was significantly higher than that of sham-operation group on the 1st, 3rd and 7th days after reperfusion respectively (125.93±3.79 vs 117.65±5.60, 140.63±4.64 vs 119.33±4.26, 131.15±2.74 vs 107.60±3.89, t=2.449, 6.763,9.899,P < 0.05-0.01). The expression of EPO of IPC group was significantly higher than that of sham-operation group on the 3rd and 7th days after perfusion respectively (141.68±3.29 vs 126.33±4.51, 138.88±2.59 vs 125.58±6.18,t=5.499,3.970, P < 0.05). CONCLUSION: ① IPC can protect the never cells in rat brain and the best time to onset of cerebral IT induced by IPC is 1 to 7 days after reperfusion. ② Neuroprotective effect of cerebral IT might be related to the expression of HIF-1α and its target gene EPO.
基金supported by the National Natural Science Foundation of China,No. 81570866 (to XLC)。
文摘Inhibiting retinal neovascularization is the optimal strategy for the treatment of retina-related diseases, but there is currently no effective treatment for retinal neovascularization. P-element-induced wimpy testis(PIWI)-interacting RNA(piRNA) is a type of small non-coding RNA implicated in a variety of diseases. In this study, we found that the expression of piR-1245 and the interacting protein PIWIL2 were remarkably increased in human retinal endothelial cells cultured in a hypoxic environment, and cell apoptosis, migration, tube formation and proliferation were remarkably enhanced in these cells. Knocking down piR-1245 inhibited the above phenomena. After intervention by a p-JAK2 activator, piR-1245 decreased the expression of hypoxia inducible factor-1α and vascular endothelial growth factor through the JAK2/STAT3 pathway. For in vivo analysis, 7-day-old newborn mice were raised in 75 ± 2% hyperoxia for 5 days and then piR-1245 in the retina was knocked down. In these mice, the number of newly formed vessels in the retina was decreased, the expressions of inflammationrelated proteins were reduced, the number of apoptotic cells in the retina was decreased, the JAK2/STAT3 pathway was inhibited, and the expressions of hypoxia inducible factor-1α and vascular endothelial growth factor were decreased. Injection of the JAK2 inhibitor JAK2/TYK2-IN-1 into the vitreous cavity inhibited retinal neovascularization in mice and reduced expression of hypoxia inducible factor-1α and vascular endothelial growth factor. These findings suggest that piR-1245 activates the JAK2/STAT3 pathway, regulates the expression of hypoxia inducible factor-1α and vascular endothelial growth factor, and promotes retinal neovascularization. Therefore, piR-1245 may be a new therapeutic target for retinal neovascularization.
基金supported by a grant from the National Natural Science Foundation of China(No.82072210)the Shanghai Municipal Science and Technology Commission,China(No.20ZR1445200)+1 种基金the Chinese Federation of Public Health Foundation(GWLM202001)the Three-Year Initiative Plan for Strengthening Public Health System Construction in Shanghai(No.GWV-10.1-XK25).
文摘The mortality of patients with severe pneumonia caused by H1N1 infection is closely related to viral replication and cytokine storm.However,the specific mechanisms triggering virus replication and cytokine storm are still not fully elucidated.Here,we identified hypoxia inducible factor-1α(HIF-1α)as one of the major host molecules that facilitates H1N1 virus replication followed by cytokine storm in alveolar epithelial cells.Specifically,HIF-1αprotein expression is upregulated after H1N1 infection.Deficiency of HIF-1αattenuates pulmonary injury,viral replication and cytokine storm in vivo.In addition,viral replication and cytokine storm were inhibited after HIF-1αknockdown in vitro.Mechanistically,the invasion of H1N1 virus into alveolar epithelial cells leads to a shift in glucose metabolism to glycolysis,with rapid production of ATP and lactate.Inhibition of glycolysis significantly suppresses viral replication and inflammatory responses.Further analysis revealed that H1N1-induced HIF-1αcan promote the expression of hexokinase 2(HK2),the key enzyme of glycolysis,and then not only provide energy for the rapid replication of H1N1 virus but also produce lactate,which reduces the accumulation of the MAVS/RIG-I complex and inhibits IFN-α/βproduction.In conclusion,this study demonstrated that the upregulation of HIF-1αby H1N1 infection augments viral replication and cytokine storm by cellular metabolic reprogramming toward glycolysis mainly through upregulation of HK2,providing a theoretical basis for finding potential targets for the treatment of severe pneumonia caused by H1N1 infection.
基金National Natural Science Foundation of China(8146061881860720+1 种基金81660683)Scientific Foundation of Double World-classes Subject Development of Jiangxi University of TCM(JXSYLXK-ZHYAO124)
文摘OBJECTIVEα-Hederin is an effective component of the traditional Chinese medicine Pulsatilla chinensis,which has been reported to exert many pharmacological activities.However,the effect ofα-hederin on metabolism is still unclear.This study aimed to illuminate the role ofα-hederin in glucose metabolism in lung cancer cells and investigate the molecular mechanism ofα-hederin.METHODS CCK8 and colony formation assays were employed to assess the anti-proliferative effects induced byα-hederin.Glucose uptake,ATP generation,and reduced lactate production were measured using kits,and an A549 tumor xenograft mouse model of lung cancer was used to assess the in vivo antitumor effect ofα-hederin(5,10 mg·kg^-1).Glycolytic-related key enzymes were detected by Western blotting and immunohisto⁃chemical staining.RESULTS Cell proliferation was significantly inhibited byα-hederin in a dose-dependent manner and thatα-hederin inhibited glucose uptake and ATP generation and reduced lactate production.Furthermore,α-hederin remarkably inhibited hexokinase 2(HK2),glucose transporters 1(GLUT1),pyruvate kinase M2(PKM2),lactate dehydro⁃genase A(LDHA),monocarboxylate transporter(MCT4),c-Myc,and hypoxia inducible factor-1α(HIF-1α)protein expres⁃sion.Using inhibitors,we proved thatα-hederin inhibits glycolysis by inhibiting glycolytic regulators.Moreover,a tumor xenograft mouse model of lung cancer further confirmed thatα-hederin inhibits lung cancer growth via inhibiting glycolysis in vivo.CONCLUSIONα-Hederin inhibits the growth of non-small cell lung cancer A549 cells by inhibiting glycolysis.The mechanism of glycolysis inhibition includesα-hederin inhibiting the expression of the glycolytic regulatory factors HIF-1α and c-Myc.
基金supported by the Science and Technology Research Foundation of Shaanxi Province, China (No.2008K14-07)the Medical and Phar macologic Research Foundation of Xi'an City, China (No.SF08004-2)
文摘Objective To observe the expression of hypoxia inducible factor-1α (HIF-1α) in the retina of rabbits with acute high intraocular pressure and to investigate the mechanism of systemic domestic recombinant human erythropoietin (rhEPO) protecting the retina from ischemia-reperfusion injury. Methods First,control group and model group were established in rabbit eyes. The acute high intraocular pressure model was established by saline perfusion into anterior chamber,and then hypodermic injection of domestic rhEPO was made. HIF-1α protein in the retina was observed by immunohistochemical staining method on days 1,3,7 and 14 after retinal ischemia-reperfusion,respectively. Results No cells with HIF-1α positive expression were observed in the retina of the control group. Cells with HIF-1α positive expression in the model group outnumbered those in the control group (P<0.01). The resemblance pattern occurred in EPO group but its degree was slightly greater than that in the model group from day 3 after ischemia-reperfusion (P<0.05). Conclusion Domestic rhEPO can down-regulate the expression of HIF-1α in the retina with acute high intraocular pressure,which may be one of the mechanisms that rhEPO protects the retina from ischemia-reperfusion injury.
基金supported by the Fund of Hubei Provincial Health Commission(No.ZY2021M080)the Medical Research Project of Jiangsu Provincial Health Commission(No.Z2021068)+1 种基金the Yancheng Medical Science and Technology Development Plan Project(No.YK2021004)the Young Scientific and Technological Talents Support Project by Jiangsu Association for Science and Technology(No.TJ-2022-097),China.
文摘Metabolic reprogramming is a common phenomenon in cancer,with aerobic glycolysis being one of its important characteristics.Hypoxia-inducible factor-1α(HIF1Α)is thought to play an important role in aerobic glycolysis.Meanwhile,naringin is a natural flavanone glycoside derived from grapefruits and many other citrus fruits.In this work,we identified glycolytic genes related to HIF1Αby analyzing the colon cancer database.The analysis of extracellular acidification rate and cell function verified the regulatory effects of HIF1Αoverexpression on glycolysis,and the proliferation and migration of colon cancer cells.Moreover,naringin was used as an inhibitor of colon cancer cells to illustrate its effect on HIF1Αfunction.The results showed that the HIF1Αand enolase 2(ENO2)levels in colon cancer tissues were highly correlated,and their high expression indicated a poor prognosis for colon cancer patients.Mechanistically,HIF1Αdirectly binds to the DNA promoter region and upregulates the transcription of ENO2;ectopic expression of ENO2 increased aerobic glycolysis in colon cancer cells.Most importantly,we found that the appropriate concentration of naringin inhibited the transcriptional activity of HIF1Α,which in turn decreased aerobic glycolysis in colon cancer cells.Generally,naringin reduces glycolysis in colon cancer cells by reducing the transcriptional activity of HIF1Αand the proliferation and invasion of colon cancer cells.This study helps to elucidate the relationship between colon cancer progression and glucose metabolism,and demonstrates the efficacy of naringin in the treatment of colon cancer.
文摘AIM:To examine changes in retinal vasculature after treatment with different oxygen concentrations from common retinopathy of prematurity(ROP) models and to determine a novel and practical ROP model.METHODS:A sample of 14 newborn Sprague-Dawley rats was used.The study group(n=7) was exposed to95%oxygen for 4h per day followed by normoxic laboratory conditions for 20 h.This cycle was repeated for 14 d.The control group(n=7) was subjected to normobaric normoxic conditions.On postnatal day 14(P14),the two groups were placed in room air for 7d.On P21,the two groups were examined using indirect ophthalmoscopy.All eyes were enucleated for immunofluorescence(IF) staining of the vasculature of retinas and analysis of vascular endothelial growth factor(VEGF),hypoxia inducible factor-1 alpha(HIF-1α),placental growth factor(PLGF) in vitreous humor,and then the rats were sacrificed by decapitation.All procedures were repeated using another litter of 14 pups.RESULTS:In the study group and under normobaric hyperoxic conditions,retinal neovascularization and peripheral avascular retina were determined in 85%of the rats through indirect ophthalmoscopic examination.Also IF staining of retina of the study group showed retarded peripheral vascular growth.The difference between the two groups for VEGF,HIF-1α and PLGF concentrations of vitreous humor was statistically significant(P=0.003,0.007,0.027 respectively).CONCLUSION:Fluctuating oxygen concentrations are primarily responsible for retinal neovascularization.Our new ROP model is practical and applicable for all retinal neovascularization studies,considering the laboratory procedures.
文摘Background:Traumatic brain edema(TBE)is caused by a specific water channel mediated by membrane aquaporins.Aquaporin-4(AQP4)plays an especially important role in this process,but the relationship between AQP4 and TBE remains unclear.The purpose of this study was to explore expression of AQP4 in the hippocampus after traumatic brain injury(TBI),as well as the effect of brain edema on skeletal protein and its function in hippocampal neurons.Methods:The adult male Wistar rats we divided into a sham group and a TBI group,the latter of which was further divided into 1,3,6,12,24 and 72 hours(h)and 15 days(d)post injury subgroups.A proper TBI model was established,and brain edema was assessed in each group by water content.We measured the abundance of various proteins,including hypoxia inducible factor-1α(HIF-1α),AQP4,microtubule-associated protein 2(MAP2),tau-5 protein,phosphorylated level of TAU,synaptophysin,cyclic adenosine monophosphate response element binding protein(CREB),phosphorylated CREB and general control nonrepressed 2,in each group.Hippocampal neurons and spatial memory test were analyzed in different time points.Results:Compared with that in the sham group,the level of AQP4 in hippocampal neurons began to significantly increase at 1 h post TBI and then decreased at 15 d post TBI.During this time frame,AQP4 level peaked at 12 and 72 h,and these peaks were closely correlated with high brain water content.HIF-1αdisplayed a similar trend.Conversely,levels of MAP2 began to decrease at 1 h post TBI and then increase at 15 d post TBI.In addition,the most severe brain edema in rats was found at 24 h post TBI,with neuronal loss and hippocampal dendritic spine injury.Compared to those in the sham group,rats in the TBI groups had significantly prolonged latency and significantly shortened exploration time.Conclusions:AQP4 level was closely correlated with severity of brain edema,and abnormal levels thereof aggravated such severity after TBI.
