OBJECTIVE Leukotriene B4(LTB4)biosynthesis and subsequently neutrophilic inflammation may provide a potential strategy for the treatment of acute lung injury(ALI)or idiopathic pulmonary fibrosis(IPF).To provide a pote...OBJECTIVE Leukotriene B4(LTB4)biosynthesis and subsequently neutrophilic inflammation may provide a potential strategy for the treatment of acute lung injury(ALI)or idiopathic pulmonary fibrosis(IPF).To provide a potential strategy for the treatment of ALI or IPF,we identified potent inhibitors of Leukotriene A4 hydrolase(LTA4H),a key enzyme in the biosynthesis of LTB4.METHODS In this study,we identified two known histone deacetylase(HDAC)inhibitors,suberanilohydroxamic acid(SAHA)and its analogue 4-(dimethylamino)-N-[7-(hydroxyamino)-7-oxoheptyl]benzamide(M344),as effective inhibitors of LTA4H using enzymatic assay,thermofluor assay,and X-ray crystallographic investigation.We next tested the effect of SAHA and M344 on endogenous LTB4 biosynthesis in neutrophils by ELISA and neutrophil migration by transwell migration assay.A murine experimental model of ALI was induced by lipopolysaccharide(LPS)inhalation.Histopathological analysis of lung tissue using H&E staining revealed the serious pulmonary damage caused by LPS treatment and the effect of the SAHA.We next examined m RNA and protein levels of pro-inflammatory cytokines in lung tissue and bronchoalveolar lavage fluid using q RT-PCR and ELISA to further investigate the underlying mechanisms of anti-inflammatory activities by SAHA.We also investigated the effects of SAHA and M344 on a murine experimental model of bleomycin(BLM)-induced IPF model.RESULTS The results of enzymatic assay and X-ray crystallography showed that both SAHA and M344 bind to LTA4H,significantly decrease LTB4 levels in neutrophil,and markedly diminish early neutrophilic inflammation in mouse models of ALI and IPF under a clinical safety dose.CONCLUSION Collectively,SAHA and M344 would provide promising agents with well-known clinical safety for potential treatment in patients with ALI and IPF via pharmacologically inhibiting LAT4H and blocking LTB4 biosynthesis.展开更多
Ovarian cancer is the most lethal and aggressive gynecological cancer with a high recurrence rate and is often diagnosed late.In ovarian cancer,multiple metabolic enzymes of lipid metabolism are abnormally expressed,r...Ovarian cancer is the most lethal and aggressive gynecological cancer with a high recurrence rate and is often diagnosed late.In ovarian cancer,multiple metabolic enzymes of lipid metabolism are abnormally expressed,resulting in metabolism disorder.As a characteristic pathway in polyunsaturated fatty acid(PUFA)metabolism,arachidonic acid(AA)metabolism is disturbed in ovarian cancer.Therefore,we established a 10-gene signature model to evaluate the prognostic risk of PUFA-related genes.This 10-gene signature has strong robustness and can play a stable predictive role in datasets of various platforms(TCGA,ICGC,and GSE17260).The high association between the risk subgroups and clinical characteristics indicated a good performance of the model.Our data further indicated that the high expression of LTA4H was positively correlated with poor prognosis in ovarian cancer.Deficiency of LTA4H enhanced sensitivity to Cisplatin and modified the characteristics of immune cell infiltration in ovarian cancer.Additionally,our results indicate that CCL5 was involved in the aberrant metabolism of the AA/LTA4H axis,which contributes to the reduction of tumor-infiltrating CD8+T cells and immune escape in ovarian cancer.These findings provide new insights into the prognosis and potential target of LTA4H/CCL5 in treating ovarian cancer.展开更多
A series of novel 1,2,3-benzotriazin-4-one derivatives were designed,synthesized and their inhibitory activities against leulcotriene A4 hydrolase aminopeptidase in vitro were evaluated.Many compounds showed moderate ...A series of novel 1,2,3-benzotriazin-4-one derivatives were designed,synthesized and their inhibitory activities against leulcotriene A4 hydrolase aminopeptidase in vitro were evaluated.Many compounds showed moderate to good activities at the concentration of 10 μmol/L.Among them,compound Ⅳ-16 exhibited the highest inhibitory activity up to 80.6% with an IC50 of 1.30 ± 0.20 μmol/L The compound Ⅳ-16 was also tested the proliferation inhibitory activities in THP1 human AML cell line and its binding model with LTA_4H enzyme by molecular docking was studied.It indicated that 1,2,3-benzotriazin-4-one was a promising scaffold for further study.The relationship between structure and inhibitory activity was also preliminarily discussed.展开更多
The enzyme leukotriene A4 (LTA4) plays an important role as precursor of slow reactive substances as LTC4, LTD4, and LTE4. It is an attractive target for molecular modeling and QSAR study. Our effort is mainly focused...The enzyme leukotriene A4 (LTA4) plays an important role as precursor of slow reactive substances as LTC4, LTD4, and LTE4. It is an attractive target for molecular modeling and QSAR study. Our effort is mainly focused on exploring the SAR for inhibitors of the LTA4 hydrolase through docking study, pharmacophore modeling and molecular descriptor study. The binding of these small molecules on LTA4 hydrolase enzyme was described by the models developed on 2D molecular descriptors, with good predictive power (39 compounds, 6 descriptors, r2 0.98, SEE 0.167, F-value 268.53, q2 0.90, r2adj 0.97, P-value < 0.0001, SD of residuals 0.15). Docking studies were employed to presume the probable binding conformation of these analogues and exploring the SAR for the compounds. The novel pharmacophore represents the ligand features that are involved in interactions with the target protein, as well as the space around the ligand occupied by the protein. The efforts are aimed to discover the SAR for the inhibitors of LTA4 hydrolase through techniques of QSAR, docking and pharmacophore.展开更多
Background and Objective:LTB4 has been shown to be involved in rheumatoid arthritis(RA)pathogenesis.The effect of Dioscin(Dio)on the LTB4 pathway of RA have not been reported yet.This study aimed at further exploring ...Background and Objective:LTB4 has been shown to be involved in rheumatoid arthritis(RA)pathogenesis.The effect of Dioscin(Dio)on the LTB4 pathway of RA have not been reported yet.This study aimed at further exploring whether Dioscin’s effects on TNF-αinduced collagen-induced arthritis(CIA)rat fibroblast-like synoviocytes(FLS)connected with the LTB4 and its receptor pathway.Materials&Methods:In this experiment,control group,TNF-αgroup,and different concentrations of Dioscin groups were established.Cell viability was evaluated using MTT assay.The levels of LTB4 in the samples of above groups were measured using ELISA.The mRNA expression levels of LTA4H,BLT1,and BLT2 were detected by quantitative real time PCR,while the expression level of LTA4H proteins were detected using western blot.The distribution of LTA4H was assessed by immunofluorescence assay.Results:the LTB4 level of TNF-αgroup in sample supernatant was higher than both control group and Dioscin groups with decreased LTB4 levels(p<0.05).Compared with the control group,the expression of LTA4H was significantly increased in TNF-αgroup(p<0.05),whereas LTA4H expressions were significantly decreased in all Dioscin groups when compared to TNF-αgroup(p<0.05).The mRNA expressions of BLT1 and BLT2 were markedly higher in TNF-αgroup than those in control group while Dioscin treatment significantly inhibited the increased expressions of BLT1 and BLT2 induced by TNF-α(p<0.05).Conclusions:These results firstly demonstrate that the protective effect of Dioscin on TNF-αinduced FLS may involve in its reducing LTB4 production by down-regulating LTA4H expression,and may inhibit its downstream pathway by decreasing LTB4 receptors levels.This findings suggest that dioscin produces a potential therapeutic effects for RA via its influencing LTA4H/LTB4/BLT pathway.展开更多
Invasive fungal infections are life-threatening,and neutrophils are vital cells of the innate immune system that defend against them.The role of LTA4H-LTB_(4)-BLT1 axis in regulation of neutrophil responses to fungal ...Invasive fungal infections are life-threatening,and neutrophils are vital cells of the innate immune system that defend against them.The role of LTA4H-LTB_(4)-BLT1 axis in regulation of neutrophil responses to fungal infection remains poorly understood.Here,we demonstrated that the LTA4H-LTB_(4)-BLT1 axis protects the host against Candida albicans and Aspergillus fumigatus,but not Cryptococcus neoformans infection,by regulating the antifungal activity of neutrophils.Our results show that deleting Lta4h or Blt1 substantially impairs the fungal-specific phagocytic capacity of neutrophils.Moreover,defective activation of the spleen tyrosine kinase(Syk)and extracellular signal-related kinase(ERK1/2)pathways in neutrophils accompanies this impairment.Mechanistically,BLT1 regulates CR3-mediated,β-1,3-glucan-induced neutrophil phagocytosis,while a physical interaction with CR3 with slight influence on its dynamics is observed.Our findings thus demonstrate that the LTA4H-LTB_(4)-BLT1 axis is essential for the phagocytic function of neutrophils in host antifungal immune response against Candida albicans and Aspergillus fumigatus.展开更多
Background Leukotrienes are arachidonic acid derivatives long known for their inflammatory properties. Leukotriene- based inflammation has been demonstrated to play a crucial role in atherosclerosis, a major risk fact...Background Leukotrienes are arachidonic acid derivatives long known for their inflammatory properties. Leukotriene- based inflammation has been demonstrated to play a crucial role in atherosclerosis, a major risk factor for several human diseases. Recently, human genetic studies from us and others suggest that single nucleotide polymorphisms （SNPs） in leukotriene pathway genes influence the risk of atherosclerotic diseases such as stroke. This study aimed to assess the role of additional leukotriene pathway genes as a stroke risk factor within the Chinese Hart population. Methods We sequenced the promoter, exonic, and intronic regions of leukotriene A4 hydrolase （LTA4H） and arachidonate 5-1ipoxygenase （ALOX5）, and then genotyped five SNPs in LTA#H and four SNPs in ALOX5 among 691 cases with stroke and 732 controls from the Chinese population. Results We detected a significant association between an intronic SNP in LTA4H （rs6538697） and stroke in our subjects （adjusted odds ratio, recessive model, 1.75; P=0.022）; and the SNP rs2029253 in ALOX5 was associated with a decreased risk of stroke （adjusted odds ratio, 0.76; 95% confidence interval, 0.59-0.97）. Conclusion Genetic variants in LTA4H and ALOX5 may modulate the risk of stroke in the Chinese Han population.展开更多
基金supported by National Natural Science Foundation of China(81402482,91313303)
文摘OBJECTIVE Leukotriene B4(LTB4)biosynthesis and subsequently neutrophilic inflammation may provide a potential strategy for the treatment of acute lung injury(ALI)or idiopathic pulmonary fibrosis(IPF).To provide a potential strategy for the treatment of ALI or IPF,we identified potent inhibitors of Leukotriene A4 hydrolase(LTA4H),a key enzyme in the biosynthesis of LTB4.METHODS In this study,we identified two known histone deacetylase(HDAC)inhibitors,suberanilohydroxamic acid(SAHA)and its analogue 4-(dimethylamino)-N-[7-(hydroxyamino)-7-oxoheptyl]benzamide(M344),as effective inhibitors of LTA4H using enzymatic assay,thermofluor assay,and X-ray crystallographic investigation.We next tested the effect of SAHA and M344 on endogenous LTB4 biosynthesis in neutrophils by ELISA and neutrophil migration by transwell migration assay.A murine experimental model of ALI was induced by lipopolysaccharide(LPS)inhalation.Histopathological analysis of lung tissue using H&E staining revealed the serious pulmonary damage caused by LPS treatment and the effect of the SAHA.We next examined m RNA and protein levels of pro-inflammatory cytokines in lung tissue and bronchoalveolar lavage fluid using q RT-PCR and ELISA to further investigate the underlying mechanisms of anti-inflammatory activities by SAHA.We also investigated the effects of SAHA and M344 on a murine experimental model of bleomycin(BLM)-induced IPF model.RESULTS The results of enzymatic assay and X-ray crystallography showed that both SAHA and M344 bind to LTA4H,significantly decrease LTB4 levels in neutrophil,and markedly diminish early neutrophilic inflammation in mouse models of ALI and IPF under a clinical safety dose.CONCLUSION Collectively,SAHA and M344 would provide promising agents with well-known clinical safety for potential treatment in patients with ALI and IPF via pharmacologically inhibiting LAT4H and blocking LTB4 biosynthesis.
基金supported by the General Program of National Natural Science Foundation of China(82272745,82072870,81972966)General Program of Natural Science Foundation of Beijing(7202224)+2 种基金the National Key Research and Development Program of China(2022YFA1104001)Youth Program of National Natural Science Foundation of China(82203102,82303801)Peking University Third Hospital Clinical Key Project(BYSY2022069)。
文摘Ovarian cancer is the most lethal and aggressive gynecological cancer with a high recurrence rate and is often diagnosed late.In ovarian cancer,multiple metabolic enzymes of lipid metabolism are abnormally expressed,resulting in metabolism disorder.As a characteristic pathway in polyunsaturated fatty acid(PUFA)metabolism,arachidonic acid(AA)metabolism is disturbed in ovarian cancer.Therefore,we established a 10-gene signature model to evaluate the prognostic risk of PUFA-related genes.This 10-gene signature has strong robustness and can play a stable predictive role in datasets of various platforms(TCGA,ICGC,and GSE17260).The high association between the risk subgroups and clinical characteristics indicated a good performance of the model.Our data further indicated that the high expression of LTA4H was positively correlated with poor prognosis in ovarian cancer.Deficiency of LTA4H enhanced sensitivity to Cisplatin and modified the characteristics of immune cell infiltration in ovarian cancer.Additionally,our results indicate that CCL5 was involved in the aberrant metabolism of the AA/LTA4H axis,which contributes to the reduction of tumor-infiltrating CD8+T cells and immune escape in ovarian cancer.These findings provide new insights into the prognosis and potential target of LTA4H/CCL5 in treating ovarian cancer.
基金financially supported by the National Natural Science Foundation of China(No.21272071)the Fundamental Research Funds for the Central Universitiessupport from Shanghai Foundation of Science and Technology(No.15431902100)
文摘A series of novel 1,2,3-benzotriazin-4-one derivatives were designed,synthesized and their inhibitory activities against leulcotriene A4 hydrolase aminopeptidase in vitro were evaluated.Many compounds showed moderate to good activities at the concentration of 10 μmol/L.Among them,compound Ⅳ-16 exhibited the highest inhibitory activity up to 80.6% with an IC50 of 1.30 ± 0.20 μmol/L The compound Ⅳ-16 was also tested the proliferation inhibitory activities in THP1 human AML cell line and its binding model with LTA_4H enzyme by molecular docking was studied.It indicated that 1,2,3-benzotriazin-4-one was a promising scaffold for further study.The relationship between structure and inhibitory activity was also preliminarily discussed.
基金Project supported by Department of Science and Technology,Govt.of India for Awarding Young Scientist Fellowship (SR/FT/LS-161/2008)
文摘The enzyme leukotriene A4 (LTA4) plays an important role as precursor of slow reactive substances as LTC4, LTD4, and LTE4. It is an attractive target for molecular modeling and QSAR study. Our effort is mainly focused on exploring the SAR for inhibitors of the LTA4 hydrolase through docking study, pharmacophore modeling and molecular descriptor study. The binding of these small molecules on LTA4 hydrolase enzyme was described by the models developed on 2D molecular descriptors, with good predictive power (39 compounds, 6 descriptors, r2 0.98, SEE 0.167, F-value 268.53, q2 0.90, r2adj 0.97, P-value < 0.0001, SD of residuals 0.15). Docking studies were employed to presume the probable binding conformation of these analogues and exploring the SAR for the compounds. The novel pharmacophore represents the ligand features that are involved in interactions with the target protein, as well as the space around the ligand occupied by the protein. The efforts are aimed to discover the SAR for the inhibitors of LTA4 hydrolase through techniques of QSAR, docking and pharmacophore.
基金supported by the National Natural Science Foundation of China(Nos.82060661,81660751,81660151)Jiangxi Provincial Natural Science Foundation of China(No.20171BAB205085).
文摘Background and Objective:LTB4 has been shown to be involved in rheumatoid arthritis(RA)pathogenesis.The effect of Dioscin(Dio)on the LTB4 pathway of RA have not been reported yet.This study aimed at further exploring whether Dioscin’s effects on TNF-αinduced collagen-induced arthritis(CIA)rat fibroblast-like synoviocytes(FLS)connected with the LTB4 and its receptor pathway.Materials&Methods:In this experiment,control group,TNF-αgroup,and different concentrations of Dioscin groups were established.Cell viability was evaluated using MTT assay.The levels of LTB4 in the samples of above groups were measured using ELISA.The mRNA expression levels of LTA4H,BLT1,and BLT2 were detected by quantitative real time PCR,while the expression level of LTA4H proteins were detected using western blot.The distribution of LTA4H was assessed by immunofluorescence assay.Results:the LTB4 level of TNF-αgroup in sample supernatant was higher than both control group and Dioscin groups with decreased LTB4 levels(p<0.05).Compared with the control group,the expression of LTA4H was significantly increased in TNF-αgroup(p<0.05),whereas LTA4H expressions were significantly decreased in all Dioscin groups when compared to TNF-αgroup(p<0.05).The mRNA expressions of BLT1 and BLT2 were markedly higher in TNF-αgroup than those in control group while Dioscin treatment significantly inhibited the increased expressions of BLT1 and BLT2 induced by TNF-α(p<0.05).Conclusions:These results firstly demonstrate that the protective effect of Dioscin on TNF-αinduced FLS may involve in its reducing LTB4 production by down-regulating LTA4H expression,and may inhibit its downstream pathway by decreasing LTB4 receptors levels.This findings suggest that dioscin produces a potential therapeutic effects for RA via its influencing LTA4H/LTB4/BLT pathway.
基金supported by the National Key Research and Development Program of China(2019YFA0508502 to XL)National Natural Science Foundation of China(31930039,31821003,91942303 to XL)+1 种基金the General Financial Grant from the China Postdoctoral Science Foundation(2020M670301 to YX)annual funding from Tsinghua University-Peking University Jointed Center for Life Sciences.
文摘Invasive fungal infections are life-threatening,and neutrophils are vital cells of the innate immune system that defend against them.The role of LTA4H-LTB_(4)-BLT1 axis in regulation of neutrophil responses to fungal infection remains poorly understood.Here,we demonstrated that the LTA4H-LTB_(4)-BLT1 axis protects the host against Candida albicans and Aspergillus fumigatus,but not Cryptococcus neoformans infection,by regulating the antifungal activity of neutrophils.Our results show that deleting Lta4h or Blt1 substantially impairs the fungal-specific phagocytic capacity of neutrophils.Moreover,defective activation of the spleen tyrosine kinase(Syk)and extracellular signal-related kinase(ERK1/2)pathways in neutrophils accompanies this impairment.Mechanistically,BLT1 regulates CR3-mediated,β-1,3-glucan-induced neutrophil phagocytosis,while a physical interaction with CR3 with slight influence on its dynamics is observed.Our findings thus demonstrate that the LTA4H-LTB_(4)-BLT1 axis is essential for the phagocytic function of neutrophils in host antifungal immune response against Candida albicans and Aspergillus fumigatus.
文摘Background Leukotrienes are arachidonic acid derivatives long known for their inflammatory properties. Leukotriene- based inflammation has been demonstrated to play a crucial role in atherosclerosis, a major risk factor for several human diseases. Recently, human genetic studies from us and others suggest that single nucleotide polymorphisms （SNPs） in leukotriene pathway genes influence the risk of atherosclerotic diseases such as stroke. This study aimed to assess the role of additional leukotriene pathway genes as a stroke risk factor within the Chinese Hart population. Methods We sequenced the promoter, exonic, and intronic regions of leukotriene A4 hydrolase （LTA4H） and arachidonate 5-1ipoxygenase （ALOX5）, and then genotyped five SNPs in LTA#H and four SNPs in ALOX5 among 691 cases with stroke and 732 controls from the Chinese population. Results We detected a significant association between an intronic SNP in LTA4H （rs6538697） and stroke in our subjects （adjusted odds ratio, recessive model, 1.75; P=0.022）; and the SNP rs2029253 in ALOX5 was associated with a decreased risk of stroke （adjusted odds ratio, 0.76; 95% confidence interval, 0.59-0.97）. Conclusion Genetic variants in LTA4H and ALOX5 may modulate the risk of stroke in the Chinese Han population.
