DI-3-n-butylphthalide is used to treat mild and moderate acute ischemic stroke.However,the precise underlying mechanism requires further investigation.In this study,we investigated the molecular mechanism of DI-3-n-bu...DI-3-n-butylphthalide is used to treat mild and moderate acute ischemic stroke.However,the precise underlying mechanism requires further investigation.In this study,we investigated the molecular mechanism of DI-3-n-butylphthalide action by various means.We used hydrogen peroxide to induce injury to PC12cells and RAW264.7 cells to mimic neuronal oxidative stress injury in stroke in vitro and examined the effects of DI-3-n-butylphthalide.We found that DI-3-nbutylphthalide pretreatment markedly inhibited the reduction in viability and reactive oxygen species production in PC12 cells caused by hydrogen peroxide and inhibited cell apoptosis.Furthermore,DI-3-n-butylphthalide pretreatment inhibited the expression of the pro-apoptotic genes Bax and Bnip3.DI-3-nbutylphthalide also promoted ubiquitination and degradation of hypoxia inducible factor 1α,the key transcription factor that regulates Bax and Bnip3 genes.These findings suggest that DI-3-n-butylphthalide exhibits a neuroprotective effect on stroke by promoting hypoxia inducible factor-1α ubiquitination and degradation and inhibiting cell apoptosis.展开更多
BACKGROUND Hepatocellular carcinoma(HCC)is a malignant tumor that occurs in the liver.Its onset is latent,and it shows high heterogeneity and can readily experience intrahepatic metastasis or systemic metastasis,which...BACKGROUND Hepatocellular carcinoma(HCC)is a malignant tumor that occurs in the liver.Its onset is latent,and it shows high heterogeneity and can readily experience intrahepatic metastasis or systemic metastasis,which seriously affects patients’quality of life.Numerous studies have shown that hypoxia inducible factor1α(HIF-1α)plays a significant role in the occurrence and development of tumors,as it promotes the formation of intratumoral vessels and plays a key role in their metastasis and invasion.Some studies have reported that caspase-3,which is induced by various factors,is involved in the apoptosis of tumor cells.AIM To investigate the expression of caspase-3 and HIF-1αand their relationship to the prognosis of patients with primary HCC complicated by pathological changes of hemorrhage and necrosis.METHODS A total of 88 patients with HCC complicated by pathological changes of hemorrhage and necrosis who were treated at our hospital from January 2017 to December 2019 were selected.The expression of caspase-3 and HIF-1αin HCC and paracancerous tissues from these patients was assessed.RESULTS The positive expression rate of caspase-3 in HCC tissues was 27.27%,which was significantly lower than that in the paracancerous tissues(P<0.05),while the positive expression rate of HIF-1αwas 72.73%,which was significantly higher than that in the paracancerous tissues(P<0.05).The positive expression rates for caspase-3 in tumor node metastasis(TNM)stage III and lymph node metastasis tissues were 2.78%and 2.50%,respectively,which were significantly lower than those in TNM stage I-II and non-lymph node metastasis tissues(P<0.05).The positive expression rates of HIF-1αin TNM stage III,lymph node metastasis,and portal vein tumor thrombus tissues were 86.11%,87.50%,and 88.00%,respectively,and these values were significantly higher than those in TNM stage I-II,non-lymph node metastasis,and portal vein tumor thrombus tissues(P<0.05).The expression of caspase-3 and HIF-1αin HCC tissues were negatively correlated(rs=−0.426,P<0.05).The median overall survival time of HCC patients was 18.90 mo(95%CI:17.20–19.91).The results of the Cox proportional risk regression model analysis showed that TNM stage,portal vein tumor thrombus,lymph node metastasis,caspase-3 expression,and HIF-1αexpression were the factors influencing patient prognosis(P<0.05).CONCLUSION The expression of caspase-3 decreases and HIF-1αincreases in HCC tissues complicated by pathological changes of hemorrhage and necrosis,and these are related to clinicopathological features and prognosis.展开更多
Objective:To evaluate whether hypoxia inducible factor(HIF-1α) targeting pharmacological drugs,echinomycin,resveratrol and CdCl_2 which inhibit HIF-1α stimulation,and mimosine,which enhances the stability of HIF-1α...Objective:To evaluate whether hypoxia inducible factor(HIF-1α) targeting pharmacological drugs,echinomycin,resveratrol and CdCl_2 which inhibit HIF-1α stimulation,and mimosine,which enhances the stability of HIF-1α present antileishmanial properties.Methods:The leishmanicidal effect of drugs was evaluated in mouse macrophages and Balb/c mouse model for cutaneous leishmaniosis.Results:Resveratrol and CdCl_2 reduced the parasite load [IC50,(27.3±2.25) μM and(24.8±0.95) μM,respectively].The IC50 value of echinomycin was(22.7±7.36) nM and mimosine did not alter the parasite load in primary macrophages.The macrophage viability IC50 values for resveratrol,echinomycin and CdCl_2 and mimosine were >40 μM,>100 nM,> 200 μM and>2 000 μM,respectively.In vivo no differences between cutaneous lesions from control,resveratrol-and echinomycin-treated Balb/c mice were detected.Conclusions:Resveratrol,echinomycin and CdCl_2 reduce parasite survival in vitro.The HIF-1α targeting pharmacological drugs require further study to more fully determine their anti-Leishmania potential and their role in therapeutic strategies.展开更多
BACKGROUND The occurrence and development of acute liver failure(ALF)is closely related to a series of inflammatory reactions,such as the production of reactive oxygen species(ROS).Hypoxia inducible factor 1α(HIF-1α...BACKGROUND The occurrence and development of acute liver failure(ALF)is closely related to a series of inflammatory reactions,such as the production of reactive oxygen species(ROS).Hypoxia inducible factor 1α(HIF-1α)is a key factor that regulates oxygen homeostasis and redox,and the stability of HIF-1αis related to the ROS level regulated by Sirtuin(Sirt)family.The activation of Sirt1 will lead to a powerful antioxidant defense system and therapeutic effects in liver disease.However,little is known about the relationship between HIF-1αand Sirt1 in the process of ALF and the molecular mechanism.AIM To investigate whether HIF-1αmay be a target of Sirt1 deacetylation and what the effects on ALF are.METHODS Mice were administrated lipopolysaccharide(LPS)/D-gal and exposed to hypoxic conditions as animal model,and resveratrol was used as an activator of Sirt1.The cellular model was established with L02 cells stimulated by LPS.N-acetyl-Lcysteine was used to remove ROS,and the expression of Sirt1 was inhibited by nicotinamide.Western blotting was used to detect Sirt1 and HIF-1αactivity and related protein expression.The possible signaling pathways involved were analyzed by immunofluorescent staining,co-immunoprecipitation,dihydroethidium staining,and Western blotting.RESULTS Compared with mice stimulated with LPS alone,the expression of Sirt1 decreased,the level of HIF-1αacetylation increased in hypoxic mice,and the levels of carbonic anhydrase 9 and Bcl-2-adenovirus E1B interacting protein 3 increased significantly,which was regulated by HIF-1α,indicating an increase of HIF-1αactivity.Under hypoxia,the down-regulation of Sirt1 activated and acetylated HIF-1αin L02 cells.The inhibition of Sirt1 significantly aggravated this effect and the massive production of ROS.The regulation of ROS was partly through peroxisome proliferatoractivated receptor alpha or AMP-activated protein kinase.Resveratrol,a Sirt1 activator,effectively relieved ALF aggravated by hypoxia,the production of ROS,and cell apoptosis.It also induced the deacetylation of HIF-1αand inhibited the activity of HIF-1α.CONCLUSION Sirt1 may have a protective effect on ALF by inducing HIF-1α deacetylation to reduce ROS.展开更多
BACKGROUND Ischemia-reperfusion injury(IRI) is a major risk associated with liver surgery and transplantation,and its pathological mechanism is complex.Interleukin-1 receptor antagonist(IL-1ra) can protect the liver f...BACKGROUND Ischemia-reperfusion injury(IRI) is a major risk associated with liver surgery and transplantation,and its pathological mechanism is complex.Interleukin-1 receptor antagonist(IL-1ra) can protect the liver from IRI.However,the regulatory mechanism of IL-1ra expression is still unclear.AIM To identify the mechanism that could protect the liver in the early stage of IRI.METHODS To screen the key genes in hepatic IRI,we performed RNA sequencing and gene enrichment analysis on liver tissue from mice with hepatic IRI.Subsequently,we verified the expression and effect of IL-1ra in hepatic IRI.We also used promoter mutagenesis and chromatin immunoprecipitation assay to search for the transcriptional regulatory sites of hypoxia-inducible factor(HIF)-1α.Finally,to explore the protective mechanism of ischemic preconditioning(IP),we examined the expression of HIF-1α and IL-1ra after IP.RESULTS We identified IL-1ra as a key regulator in hepatic IRI.The expression of IL-1ra was significantly upregulated after hepatic IRI both in vivo and in vitro.Furthermore,we found that HIF-1αregulated Il-1ra transcription in response to hypoxia.Increased HIF-1α accumulation promoted IL-1ra expression,whereas inhibition of HIF-1α exhibited the opposite effect.We also confirmed a predominant role for hypoxia response element in the regulation of Il1ra transcription by HIF-1αactivation.Of note,we demonstrated that IP protects against hepatic IRI by inducing IL-1ra expression,which is mediated through HIF-1α.CONCLUSION We demonstrated that ischemia or hypoxia leads to increased expression of IL-1ra through HIF-1α.Importantly,IP protects the liver from IRI via the HIF-1α–IL-1ra pathway.展开更多
The cornea is an avascular,transparent tissue that is essential for visual function.Any disturbance to the corneal transparency will result in a severe vision loss.Due to the avascular nature,the cornea acquires most ...The cornea is an avascular,transparent tissue that is essential for visual function.Any disturbance to the corneal transparency will result in a severe vision loss.Due to the avascular nature,the cornea acquires most of the oxygen supply directly or indirectly from the atmosphere.Corneal tissue hypoxia has been noticed to influence the structure and function of the cornea for decades.The etiology of hypoxia of the cornea is distinct from the rest of the body,mainly due to the separation of cornea from the atmosphere,such as prolonged contact lens wearing or closed eyes.Corneal hypoxia can also be found in corneal inflammation and injury when a higher oxygen requirement exceeds the oxygen supply.Systemic hypoxic state during lung diseases or high altitude also leads to corneal hypoxia when a second oxygen consumption route from aqueous humor gets blocked.Hypoxia affects the cornea in multiple aspects,including disturbance of the epithelium barrier function,corneal edema due to endothelial dysfunction and metabolism changes in the stroma,and thinning of corneal stroma.Cornea has also evolved mechanisms to adapt to the hypoxic state initiated by the activation of hypoxia inducible factor(HIF).The aim of this review is to introduce the pathology of cornea under hypoxia and the mechanism of hypoxia adaptation,to discuss the current animal models used in this field,and future research directions.展开更多
In most cases, cancer develops as a result of non-inheritable somatic mutations (epimutations), acquired by the individual adult cell, during the evolution of the cell, and propagated into an expanding clone of progen...In most cases, cancer develops as a result of non-inheritable somatic mutations (epimutations), acquired by the individual adult cell, during the evolution of the cell, and propagated into an expanding clone of progeny of the cells by natural selection [1]. The role of microenvironment in selection for such acquired mutations, or epimutations, is a focus of scientific research in carcinogenesis [2]. Here we describe a defective DNA response to hypoxia due to epigenetic aberrancies, in cancer cellular biology [3]. We also summarize a literature review on hypoxia mediated epigenetic responses, and its role in carcinogenesis and metastasis. Further, we review a novel method of treating hypoxic solid tumors with a combination of epigenetic modifiers with both in vitro and in vivo results in human, translating to an improved prognosis and clinical outcome. We propose that this approach both independently and synergistically (with the current standard of care) can provide an improved outcome.展开更多
Although multiple advances have been made in systemic therapy for renal cell carcinoma(RCC),metastatic RCC remains incurable.In the current review,we focus on the underlying biology of RCC and plausible mechanisms of ...Although multiple advances have been made in systemic therapy for renal cell carcinoma(RCC),metastatic RCC remains incurable.In the current review,we focus on the underlying biology of RCC and plausible mechanisms of metastasis.We further outline evolving strategies to combat metastasis through adjuvant therapy.Finally,we discuss clinical patterns of metastasis in RCC and how distinct systemic therapy approaches may be considered based on the anatomic location of metastasis.展开更多
Cobalt is one of the main components of metal hip prostheses and cobalt nanoparticles(CoNPs)produced from wear cause inflammation,bone lyses and cytotoxicity at high concentrations.Cobalt ions mimic hypoxia in the pre...Cobalt is one of the main components of metal hip prostheses and cobalt nanoparticles(CoNPs)produced from wear cause inflammation,bone lyses and cytotoxicity at high concentrations.Cobalt ions mimic hypoxia in the presence of normal oxygen levels,and activate hypoxic signalling by stabilising hypoxia inducible transcription factor 1α(HIF1α).This study aimed to assess in vitro the functional role of HIF1αin CoNP induced cellular cytotoxicity.HIF1α,lysosomal pH,tumour necrosis factorαand interleukin 1βexpression were analysed in THP-1 macrophages treated with CoNP(0,10 and 100μg/mL).HIF1αknock out assays were performed using small interfering RNA to assess the role of HIF1αin CoNP-induced cytotoxicity.Increasing CoNP concentration increased lysosomal activity and acidity in THP-1 macrophages.Higher doses of CoNP significantly reduced cell viability,stimulated caspase 3 activity and apoptosis.Reducing HIF1αactivity increased the pro-inflammatory activity of tumour necrosis factorαand interleukin 1β,but had no significant impact on cellular cytotoxicity.This suggests that whilst CoNP promotes cytotoxicity and cellular inflammation,the apoptotic mechanism is not dependent on HIF1α.展开更多
OBJECTIVE To investigate berberine(BBR)attenuates arthritis in adjuvant-induced arthritic(AA)rats associated with regulating the energy metabolism and correcting the polarization of macrophages through activation of A...OBJECTIVE To investigate berberine(BBR)attenuates arthritis in adjuvant-induced arthritic(AA)rats associated with regulating the energy metabolism and correcting the polarization of macrophages through activation of AMP-activated protein kinase(AMPK)and inhibition of hypoxia inducible factor 1α(HIF-1α).METHODS AA rats were treated with BBR(40,80,or 160 mg·kg-1)from days 15 to 29 after immunization.The histopathology of ankle joint was examined through hematoxylin-eosin(HE)staining.The concentrations of tumour necrosis factor-α(TNF-α),interleukin-6(IL-6),IL-1β,IL-2,IL-17A,interferon-gamma(IFN-γ),monocyte chemotactic protein 1(MCP-1),IL-4,IL-10,transforming growth factor-β1(TGF-β1),ATP,and lactic acid were measured by using ELISA kits.The percentage of M1 and M2 macro⁃phage cells in joint tissues were evaluated by immune-fluorescence.The expressions of p-AMPK and HIF-1αin joint of AA rats were determined according to immunohistochemistry analysis.The migration of macrophage was detected by Transwell assays.The expression of inducible nitric oxide synthase(iNOS),Arginase-1(Arg1),p-AMPK,AMPK and HIF-1αwere examined by Western blotting.The labeled macrophages were observed with laser confocal microscopy.RESULTS BBR relieved signs and symptoms of AA rats and reversed pathological changes.BBR treatment group exhibited decreases in pro-inflammatory cytokines(TNF-α,IL-1β,IL-6,IL-2,IL-17A,IFN-γ,and MCP-1)coupled with increases anti-inflammatory cytokines(IL-4,IL-10,TGF-β1)in the serum.The number of M1 macrophage was reduced,while the number of M2 macrophage was increased in BBR group joint tissues.Moreover,BBR showed marked up-regu⁃lation the expression of p-AMPK and down-regulation the expression of HIF-1αin joint of AA rats.Next in vitro study,we found BBR up-regulated the expression of p-AMPK,Arg1(M2 marker)and down-regulated the expression of HIF-1α,iNOS(M1 marker)induced by LPS in peritoneal macrophages from normal SD rat.Furthermore,BBR treatment inhibited the migration of macrophages stimulated by LPS.The level of ATP was elevated and lactic acid was reduced in LPSinduced macrophages after treated by BBR.However,Compound C significantly attenuated the effects of BBR on acti⁃vated macrophages.CONCLUSION BBR alleviates inflammation by regulating energy metabolism and correcting the polarization of macrophage through AMPK-HIF-1αpathway.BBR might have great therapeutic value for RA.展开更多
Aim:Therapeutic agents suppressing bone remodeling have been clinically approved to delay metastatic progression and skeletal-related events in patients with bone metastasis.However,therapeutic agents including zoledr...Aim:Therapeutic agents suppressing bone remodeling have been clinically approved to delay metastatic progression and skeletal-related events in patients with bone metastasis.However,therapeutic agents including zoledronic acid(ZA)are insufficient to regress established bone metastasis.Therefore,new treatment strategies are desired,and unraveling the status of cancer cells during bone metastatic progression will help develop therapeutic strategies.Methods:We developed a unique multiplexed reporter system for bioluminescent imaging(MRS-BLI)using three luciferase reporter genes.This system allows for the noninvasive and quantitative monitoring of tumor growth and activities of nuclear factor-kappa B(NF-κB)and hypoxia-inducible factor(HIF),which are the key transcriptional factors in response to inflammation and hypoxia,respectively.PC-3/MRS-BLI,a human prostate cancer cell line that stably retains the MRS-BLI reporter genes,was applied to the caudal-artery injection model of bone metastasis to observe the status of cancer cells during bone metastasis development and ZA treatment(<1 month).Results:MRS-BLI reveals key events during the bone metastasis development:NF-κB and HIF are activated in cancer cells after migration to the bone marrow and are transiently reduced,followed by rapid activation before proliferation begins.ZA treatment suppresses the growth of metastasized cancer cells by suppressing NF-κB and HIF activities that may be indirectly induced by osteoclast activation.Conclusion:By visualizing the NF-κB and HIF activities of PC-3/MRS-BLI in bone,MRS-BLI has enabled new discoveries regarding the regulation of bone metastases.Further analysis of the progression of bone metastases using MRS-BLI may provide important information for developing new therapeutic strategies.展开更多
Background and Aims:Reducing reactive oxygen species(ROS)production has proven an effective way for allevi-ating oxidative stress during ischemia-reperfusion injury(IRI).Moreover,inhibition of Rac1 could reduce ROS pr...Background and Aims:Reducing reactive oxygen species(ROS)production has proven an effective way for allevi-ating oxidative stress during ischemia-reperfusion injury(IRI).Moreover,inhibition of Rac1 could reduce ROS pro-duction and prevent oxidative stress injury.Previous stud-ies have suggested a positive interactivation feedback loop between Rac1 and hypoxia-inducible factor(HIF)-1α,the latter being up-regulated early during ischemia.The posi-tive inter-activation between Rac1 and HIF-1αwould ag-gravate ROS production,thereby promoting IRI.This study was designed to verify the effects of Rac1 inhibition on he-patic IRI both at animal and cellular levels and to explore the interaction between Rac1 and HIF-1αduring hepatic IRI.Methods:C57B/6 mice and AML-12 cells were used for the construction of hepatic IRI animal and cell models.Rac1 inhibition was achieved by NSC23766(a specific Rac1 inhibitor).Lentiviral vectors were used for Rac1 knock-down.At designated time points,serum and liver tissues were collected from the mice and treated cells were col-lected for further analysis.Results:NSC23766 treatment significantly alleviated the hepatic IRI in mice,manifesting as lower vacuolation score and less apoptosis cells,lower ROS and serum/liver alanine aminotransferase/aspartate aminotransferase levels,and fewer activated inflammatory cells.IRI of AML-12 was also alleviated by 50μM NSC23766 or Rac1-knockdown,manifesting as reduced cell apoptosis,less extensive interruption of mitochondrial membrane po-tential,down-regulation of apoptosis,and effects on DNA damage-related proteins.Interestingly,Rac1 knockdown also down-regulated the expression level of HIF-1α.Con-clusions:Our study supports a protective effect of Rac1 inhibition on hepatic IRI.Aside from the classic topics of reducing ROS production and oxidative stress,our study showed an interaction between Rac1 and HIF-1αsignaling during hepatic IRI.展开更多
文摘DI-3-n-butylphthalide is used to treat mild and moderate acute ischemic stroke.However,the precise underlying mechanism requires further investigation.In this study,we investigated the molecular mechanism of DI-3-n-butylphthalide action by various means.We used hydrogen peroxide to induce injury to PC12cells and RAW264.7 cells to mimic neuronal oxidative stress injury in stroke in vitro and examined the effects of DI-3-n-butylphthalide.We found that DI-3-nbutylphthalide pretreatment markedly inhibited the reduction in viability and reactive oxygen species production in PC12 cells caused by hydrogen peroxide and inhibited cell apoptosis.Furthermore,DI-3-n-butylphthalide pretreatment inhibited the expression of the pro-apoptotic genes Bax and Bnip3.DI-3-nbutylphthalide also promoted ubiquitination and degradation of hypoxia inducible factor 1α,the key transcription factor that regulates Bax and Bnip3 genes.These findings suggest that DI-3-n-butylphthalide exhibits a neuroprotective effect on stroke by promoting hypoxia inducible factor-1α ubiquitination and degradation and inhibiting cell apoptosis.
基金Supported by Research Project for Jiangxi Educational Department,No.180086.
文摘BACKGROUND Hepatocellular carcinoma(HCC)is a malignant tumor that occurs in the liver.Its onset is latent,and it shows high heterogeneity and can readily experience intrahepatic metastasis or systemic metastasis,which seriously affects patients’quality of life.Numerous studies have shown that hypoxia inducible factor1α(HIF-1α)plays a significant role in the occurrence and development of tumors,as it promotes the formation of intratumoral vessels and plays a key role in their metastasis and invasion.Some studies have reported that caspase-3,which is induced by various factors,is involved in the apoptosis of tumor cells.AIM To investigate the expression of caspase-3 and HIF-1αand their relationship to the prognosis of patients with primary HCC complicated by pathological changes of hemorrhage and necrosis.METHODS A total of 88 patients with HCC complicated by pathological changes of hemorrhage and necrosis who were treated at our hospital from January 2017 to December 2019 were selected.The expression of caspase-3 and HIF-1αin HCC and paracancerous tissues from these patients was assessed.RESULTS The positive expression rate of caspase-3 in HCC tissues was 27.27%,which was significantly lower than that in the paracancerous tissues(P<0.05),while the positive expression rate of HIF-1αwas 72.73%,which was significantly higher than that in the paracancerous tissues(P<0.05).The positive expression rates for caspase-3 in tumor node metastasis(TNM)stage III and lymph node metastasis tissues were 2.78%and 2.50%,respectively,which were significantly lower than those in TNM stage I-II and non-lymph node metastasis tissues(P<0.05).The positive expression rates of HIF-1αin TNM stage III,lymph node metastasis,and portal vein tumor thrombus tissues were 86.11%,87.50%,and 88.00%,respectively,and these values were significantly higher than those in TNM stage I-II,non-lymph node metastasis,and portal vein tumor thrombus tissues(P<0.05).The expression of caspase-3 and HIF-1αin HCC tissues were negatively correlated(rs=−0.426,P<0.05).The median overall survival time of HCC patients was 18.90 mo(95%CI:17.20–19.91).The results of the Cox proportional risk regression model analysis showed that TNM stage,portal vein tumor thrombus,lymph node metastasis,caspase-3 expression,and HIF-1αexpression were the factors influencing patient prognosis(P<0.05).CONCLUSION The expression of caspase-3 decreases and HIF-1αincreases in HCC tissues complicated by pathological changes of hemorrhage and necrosis,and these are related to clinicopathological features and prognosis.
基金supported by Fundacao de Amparo a Pesquisa do Estado de Sao Paulo,Conselho Nacional de Desenvolvimento Científico e Tecnologico (NO.2009/10771-9)Coordenacao de Aperfeicoamento de Pessoal de Nível Superior (NO.301052/2009-3),Brazil
文摘Objective:To evaluate whether hypoxia inducible factor(HIF-1α) targeting pharmacological drugs,echinomycin,resveratrol and CdCl_2 which inhibit HIF-1α stimulation,and mimosine,which enhances the stability of HIF-1α present antileishmanial properties.Methods:The leishmanicidal effect of drugs was evaluated in mouse macrophages and Balb/c mouse model for cutaneous leishmaniosis.Results:Resveratrol and CdCl_2 reduced the parasite load [IC50,(27.3±2.25) μM and(24.8±0.95) μM,respectively].The IC50 value of echinomycin was(22.7±7.36) nM and mimosine did not alter the parasite load in primary macrophages.The macrophage viability IC50 values for resveratrol,echinomycin and CdCl_2 and mimosine were >40 μM,>100 nM,> 200 μM and>2 000 μM,respectively.In vivo no differences between cutaneous lesions from control,resveratrol-and echinomycin-treated Balb/c mice were detected.Conclusions:Resveratrol,echinomycin and CdCl_2 reduce parasite survival in vitro.The HIF-1α targeting pharmacological drugs require further study to more fully determine their anti-Leishmania potential and their role in therapeutic strategies.
基金Supported by National Natural Science Foundation of China,No. 82070609
文摘BACKGROUND The occurrence and development of acute liver failure(ALF)is closely related to a series of inflammatory reactions,such as the production of reactive oxygen species(ROS).Hypoxia inducible factor 1α(HIF-1α)is a key factor that regulates oxygen homeostasis and redox,and the stability of HIF-1αis related to the ROS level regulated by Sirtuin(Sirt)family.The activation of Sirt1 will lead to a powerful antioxidant defense system and therapeutic effects in liver disease.However,little is known about the relationship between HIF-1αand Sirt1 in the process of ALF and the molecular mechanism.AIM To investigate whether HIF-1αmay be a target of Sirt1 deacetylation and what the effects on ALF are.METHODS Mice were administrated lipopolysaccharide(LPS)/D-gal and exposed to hypoxic conditions as animal model,and resveratrol was used as an activator of Sirt1.The cellular model was established with L02 cells stimulated by LPS.N-acetyl-Lcysteine was used to remove ROS,and the expression of Sirt1 was inhibited by nicotinamide.Western blotting was used to detect Sirt1 and HIF-1αactivity and related protein expression.The possible signaling pathways involved were analyzed by immunofluorescent staining,co-immunoprecipitation,dihydroethidium staining,and Western blotting.RESULTS Compared with mice stimulated with LPS alone,the expression of Sirt1 decreased,the level of HIF-1αacetylation increased in hypoxic mice,and the levels of carbonic anhydrase 9 and Bcl-2-adenovirus E1B interacting protein 3 increased significantly,which was regulated by HIF-1α,indicating an increase of HIF-1αactivity.Under hypoxia,the down-regulation of Sirt1 activated and acetylated HIF-1αin L02 cells.The inhibition of Sirt1 significantly aggravated this effect and the massive production of ROS.The regulation of ROS was partly through peroxisome proliferatoractivated receptor alpha or AMP-activated protein kinase.Resveratrol,a Sirt1 activator,effectively relieved ALF aggravated by hypoxia,the production of ROS,and cell apoptosis.It also induced the deacetylation of HIF-1αand inhibited the activity of HIF-1α.CONCLUSION Sirt1 may have a protective effect on ALF by inducing HIF-1α deacetylation to reduce ROS.
基金the National Natural Science Foundation of China,No.81670600.
文摘BACKGROUND Ischemia-reperfusion injury(IRI) is a major risk associated with liver surgery and transplantation,and its pathological mechanism is complex.Interleukin-1 receptor antagonist(IL-1ra) can protect the liver from IRI.However,the regulatory mechanism of IL-1ra expression is still unclear.AIM To identify the mechanism that could protect the liver in the early stage of IRI.METHODS To screen the key genes in hepatic IRI,we performed RNA sequencing and gene enrichment analysis on liver tissue from mice with hepatic IRI.Subsequently,we verified the expression and effect of IL-1ra in hepatic IRI.We also used promoter mutagenesis and chromatin immunoprecipitation assay to search for the transcriptional regulatory sites of hypoxia-inducible factor(HIF)-1α.Finally,to explore the protective mechanism of ischemic preconditioning(IP),we examined the expression of HIF-1α and IL-1ra after IP.RESULTS We identified IL-1ra as a key regulator in hepatic IRI.The expression of IL-1ra was significantly upregulated after hepatic IRI both in vivo and in vitro.Furthermore,we found that HIF-1αregulated Il-1ra transcription in response to hypoxia.Increased HIF-1α accumulation promoted IL-1ra expression,whereas inhibition of HIF-1α exhibited the opposite effect.We also confirmed a predominant role for hypoxia response element in the regulation of Il1ra transcription by HIF-1αactivation.Of note,we demonstrated that IP protects against hepatic IRI by inducing IL-1ra expression,which is mediated through HIF-1α.CONCLUSION We demonstrated that ischemia or hypoxia leads to increased expression of IL-1ra through HIF-1α.Importantly,IP protects the liver from IRI via the HIF-1α–IL-1ra pathway.
文摘The cornea is an avascular,transparent tissue that is essential for visual function.Any disturbance to the corneal transparency will result in a severe vision loss.Due to the avascular nature,the cornea acquires most of the oxygen supply directly or indirectly from the atmosphere.Corneal tissue hypoxia has been noticed to influence the structure and function of the cornea for decades.The etiology of hypoxia of the cornea is distinct from the rest of the body,mainly due to the separation of cornea from the atmosphere,such as prolonged contact lens wearing or closed eyes.Corneal hypoxia can also be found in corneal inflammation and injury when a higher oxygen requirement exceeds the oxygen supply.Systemic hypoxic state during lung diseases or high altitude also leads to corneal hypoxia when a second oxygen consumption route from aqueous humor gets blocked.Hypoxia affects the cornea in multiple aspects,including disturbance of the epithelium barrier function,corneal edema due to endothelial dysfunction and metabolism changes in the stroma,and thinning of corneal stroma.Cornea has also evolved mechanisms to adapt to the hypoxic state initiated by the activation of hypoxia inducible factor(HIF).The aim of this review is to introduce the pathology of cornea under hypoxia and the mechanism of hypoxia adaptation,to discuss the current animal models used in this field,and future research directions.
文摘In most cases, cancer develops as a result of non-inheritable somatic mutations (epimutations), acquired by the individual adult cell, during the evolution of the cell, and propagated into an expanding clone of progeny of the cells by natural selection [1]. The role of microenvironment in selection for such acquired mutations, or epimutations, is a focus of scientific research in carcinogenesis [2]. Here we describe a defective DNA response to hypoxia due to epigenetic aberrancies, in cancer cellular biology [3]. We also summarize a literature review on hypoxia mediated epigenetic responses, and its role in carcinogenesis and metastasis. Further, we review a novel method of treating hypoxic solid tumors with a combination of epigenetic modifiers with both in vitro and in vivo results in human, translating to an improved prognosis and clinical outcome. We propose that this approach both independently and synergistically (with the current standard of care) can provide an improved outcome.
文摘Although multiple advances have been made in systemic therapy for renal cell carcinoma(RCC),metastatic RCC remains incurable.In the current review,we focus on the underlying biology of RCC and plausible mechanisms of metastasis.We further outline evolving strategies to combat metastasis through adjuvant therapy.Finally,we discuss clinical patterns of metastasis in RCC and how distinct systemic therapy approaches may be considered based on the anatomic location of metastasis.
文摘Cobalt is one of the main components of metal hip prostheses and cobalt nanoparticles(CoNPs)produced from wear cause inflammation,bone lyses and cytotoxicity at high concentrations.Cobalt ions mimic hypoxia in the presence of normal oxygen levels,and activate hypoxic signalling by stabilising hypoxia inducible transcription factor 1α(HIF1α).This study aimed to assess in vitro the functional role of HIF1αin CoNP induced cellular cytotoxicity.HIF1α,lysosomal pH,tumour necrosis factorαand interleukin 1βexpression were analysed in THP-1 macrophages treated with CoNP(0,10 and 100μg/mL).HIF1αknock out assays were performed using small interfering RNA to assess the role of HIF1αin CoNP-induced cytotoxicity.Increasing CoNP concentration increased lysosomal activity and acidity in THP-1 macrophages.Higher doses of CoNP significantly reduced cell viability,stimulated caspase 3 activity and apoptosis.Reducing HIF1αactivity increased the pro-inflammatory activity of tumour necrosis factorαand interleukin 1β,but had no significant impact on cellular cytotoxicity.This suggests that whilst CoNP promotes cytotoxicity and cellular inflammation,the apoptotic mechanism is not dependent on HIF1α.
基金National Natural Science Foundation of China(81703529)
文摘OBJECTIVE To investigate berberine(BBR)attenuates arthritis in adjuvant-induced arthritic(AA)rats associated with regulating the energy metabolism and correcting the polarization of macrophages through activation of AMP-activated protein kinase(AMPK)and inhibition of hypoxia inducible factor 1α(HIF-1α).METHODS AA rats were treated with BBR(40,80,or 160 mg·kg-1)from days 15 to 29 after immunization.The histopathology of ankle joint was examined through hematoxylin-eosin(HE)staining.The concentrations of tumour necrosis factor-α(TNF-α),interleukin-6(IL-6),IL-1β,IL-2,IL-17A,interferon-gamma(IFN-γ),monocyte chemotactic protein 1(MCP-1),IL-4,IL-10,transforming growth factor-β1(TGF-β1),ATP,and lactic acid were measured by using ELISA kits.The percentage of M1 and M2 macro⁃phage cells in joint tissues were evaluated by immune-fluorescence.The expressions of p-AMPK and HIF-1αin joint of AA rats were determined according to immunohistochemistry analysis.The migration of macrophage was detected by Transwell assays.The expression of inducible nitric oxide synthase(iNOS),Arginase-1(Arg1),p-AMPK,AMPK and HIF-1αwere examined by Western blotting.The labeled macrophages were observed with laser confocal microscopy.RESULTS BBR relieved signs and symptoms of AA rats and reversed pathological changes.BBR treatment group exhibited decreases in pro-inflammatory cytokines(TNF-α,IL-1β,IL-6,IL-2,IL-17A,IFN-γ,and MCP-1)coupled with increases anti-inflammatory cytokines(IL-4,IL-10,TGF-β1)in the serum.The number of M1 macrophage was reduced,while the number of M2 macrophage was increased in BBR group joint tissues.Moreover,BBR showed marked up-regu⁃lation the expression of p-AMPK and down-regulation the expression of HIF-1αin joint of AA rats.Next in vitro study,we found BBR up-regulated the expression of p-AMPK,Arg1(M2 marker)and down-regulated the expression of HIF-1α,iNOS(M1 marker)induced by LPS in peritoneal macrophages from normal SD rat.Furthermore,BBR treatment inhibited the migration of macrophages stimulated by LPS.The level of ATP was elevated and lactic acid was reduced in LPSinduced macrophages after treated by BBR.However,Compound C significantly attenuated the effects of BBR on acti⁃vated macrophages.CONCLUSION BBR alleviates inflammation by regulating energy metabolism and correcting the polarization of macrophage through AMPK-HIF-1αpathway.BBR might have great therapeutic value for RA.
基金supported by a Grant-in-Aid for Scientific Research on Innovative Areas“Integrative Research on Cancer Microenvironment Networks from the Ministry of Education”,Culture,Sports,Science and Technology of Japan(S.K-K),Grant-in-Aid for Young Scientist(B)(T.Ku)and Princess Takamatsu Cancer Research Fund(T.Ku).
文摘Aim:Therapeutic agents suppressing bone remodeling have been clinically approved to delay metastatic progression and skeletal-related events in patients with bone metastasis.However,therapeutic agents including zoledronic acid(ZA)are insufficient to regress established bone metastasis.Therefore,new treatment strategies are desired,and unraveling the status of cancer cells during bone metastatic progression will help develop therapeutic strategies.Methods:We developed a unique multiplexed reporter system for bioluminescent imaging(MRS-BLI)using three luciferase reporter genes.This system allows for the noninvasive and quantitative monitoring of tumor growth and activities of nuclear factor-kappa B(NF-κB)and hypoxia-inducible factor(HIF),which are the key transcriptional factors in response to inflammation and hypoxia,respectively.PC-3/MRS-BLI,a human prostate cancer cell line that stably retains the MRS-BLI reporter genes,was applied to the caudal-artery injection model of bone metastasis to observe the status of cancer cells during bone metastasis development and ZA treatment(<1 month).Results:MRS-BLI reveals key events during the bone metastasis development:NF-κB and HIF are activated in cancer cells after migration to the bone marrow and are transiently reduced,followed by rapid activation before proliferation begins.ZA treatment suppresses the growth of metastasized cancer cells by suppressing NF-κB and HIF activities that may be indirectly induced by osteoclast activation.Conclusion:By visualizing the NF-κB and HIF activities of PC-3/MRS-BLI in bone,MRS-BLI has enabled new discoveries regarding the regulation of bone metastases.Further analysis of the progression of bone metastases using MRS-BLI may provide important information for developing new therapeutic strategies.
基金This work was supported by the grants from the National Natural Science Foundation of China(No.81671576)the Shanghai Sailing Program(No.18YF1429200),and the Nat-ural Science Foundation of Shanghai(No.18ZR1449700).
文摘Background and Aims:Reducing reactive oxygen species(ROS)production has proven an effective way for allevi-ating oxidative stress during ischemia-reperfusion injury(IRI).Moreover,inhibition of Rac1 could reduce ROS pro-duction and prevent oxidative stress injury.Previous stud-ies have suggested a positive interactivation feedback loop between Rac1 and hypoxia-inducible factor(HIF)-1α,the latter being up-regulated early during ischemia.The posi-tive inter-activation between Rac1 and HIF-1αwould ag-gravate ROS production,thereby promoting IRI.This study was designed to verify the effects of Rac1 inhibition on he-patic IRI both at animal and cellular levels and to explore the interaction between Rac1 and HIF-1αduring hepatic IRI.Methods:C57B/6 mice and AML-12 cells were used for the construction of hepatic IRI animal and cell models.Rac1 inhibition was achieved by NSC23766(a specific Rac1 inhibitor).Lentiviral vectors were used for Rac1 knock-down.At designated time points,serum and liver tissues were collected from the mice and treated cells were col-lected for further analysis.Results:NSC23766 treatment significantly alleviated the hepatic IRI in mice,manifesting as lower vacuolation score and less apoptosis cells,lower ROS and serum/liver alanine aminotransferase/aspartate aminotransferase levels,and fewer activated inflammatory cells.IRI of AML-12 was also alleviated by 50μM NSC23766 or Rac1-knockdown,manifesting as reduced cell apoptosis,less extensive interruption of mitochondrial membrane po-tential,down-regulation of apoptosis,and effects on DNA damage-related proteins.Interestingly,Rac1 knockdown also down-regulated the expression level of HIF-1α.Con-clusions:Our study supports a protective effect of Rac1 inhibition on hepatic IRI.Aside from the classic topics of reducing ROS production and oxidative stress,our study showed an interaction between Rac1 and HIF-1αsignaling during hepatic IRI.
