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
OBJECTIVE Previously we demonstrated the neuroprotective effect of 5-lipoxygenase(5-LOX)inhibitor as well as cysteinyl leukotriene receptor 1(Cys LT1)antagoniston rotenone-induced microglial activation and neuronal de...OBJECTIVE Previously we demonstrated the neuroprotective effect of 5-lipoxygenase(5-LOX)inhibitor as well as cysteinyl leukotriene receptor 1(Cys LT1)antagoniston rotenone-induced microglial activation and neuronal death.In this study,we determined the effects of 5-LOX inhibitor zileuton and Cys LT1 antagonist montelukast on neurotoxicity induced by 1-methyl-4-phenylpyridine(MPP+)in an in vitro model of Parkinson disease(PD).METHODS The neurotoxicity of MPP+,a neurotoxin relevant to PD,on the PC12 cells was measured by MTT assay,lactate dehydrogenase(LDH)release and double fluorescence staining with Hoechst/propidiumiodide(PI).The protective effects of 5-LOX inhibitor zileuton and Cys LT1 antagonist montelukast were investigated by the above methods.RESULTS We found that exposure of PC12 cells to MPP+led to a reduced cell viability and an increased level of LDH in a concentration-dependent manner.Pretreatment with zileuton and montelukast significantly attenuated viability loss and LDH release in MPP+-treated PC12 cells.Furthermore,MPP+increasednecrotic cell death in PC12 cells.Administration of montelukast significantly decreased MPP+-induced cell necrosis in PC12 cells.CONCLUSION The 5-LOX inhibitor zileuton and Cys LT1 antagonist montelukast have a neuroprotective effects on MPP+-induced neurotoxicity in PC12 cells.The 5-LOX inhibitor and Cys LT1 antagonist might raise a possibility as potential therapeutic agent for PD and other inflammation-related the central nervous system disorders.展开更多
OBJECTIVE We have recently reported that cysteinyl leukotriene(Cys LT) signaling plays an important role in microglial interleukin(IL)-1β secretion and subsequent neurotoxicity.The present study aimed to examine micr...OBJECTIVE We have recently reported that cysteinyl leukotriene(Cys LT) signaling plays an important role in microglial interleukin(IL)-1β secretion and subsequent neurotoxicity.The present study aimed to examine microglial morphological changes and the upstream molecular underlying IL^(-1)β production in Cys LT receptor agonist leukotriene D4(LTD4)-treated BV2 microglia in vitro.METHODS Twenty-four hours after murine microglial BV2 cells were stimulated with LTD4(1-100 nmol·L^(-1)),the cell proliferation and morphology were observed.The expression level of cysteinyl aspartate-specific protease 1(CASP1) protein was measured by Western blotin BV2 cells.In addition,BV2 cells were pretreated with or without CysLT1 receptor antagonist montelukast for 1 h and the effects of monte-lukaston LTD4-stimulated microglial activation and CASP1 expression were evaluated.RESULTS The number of BV2 cells had an increasing tendency after 24 h treatment with LTD4,but no significant differences were observed between the control and LTD4-treated cells(P>0.05).Under basal and resting conditions,BV2 microglial cells displayed a ramified morphology.However,LTD4 at 100 nmool·L^(-1) drove microglial morphological changes from a ramified towards an amoeboid shape.The expression of CASP1 protein was significantly upregulated in 100 nmool·L^(-1) LTD4-treated BV2 microglia(P<0.01).Furthermore,pretreatment with CysLT1 receptor antagonist montelukast prevented cell morphological changes and suppressed the increased CASP1 expression in LTD4-treated BV2 cells(P<0.05).CONCLUSION Cys LT receptor agonist LTD4 induces morphological changes and CASP1 expressionin BV2 microglia,which can be inhibited by CysLT1 antagonist.These results suggest the involvement of Cys LT signaling in microglial morphological changes and CASP1 expression.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The project supported National Natural Science Foundation of China(81273491)the Zhejiang Provincial Natural Science Foundation(LY12H31010)
文摘OBJECTIVE Previously we demonstrated the neuroprotective effect of 5-lipoxygenase(5-LOX)inhibitor as well as cysteinyl leukotriene receptor 1(Cys LT1)antagoniston rotenone-induced microglial activation and neuronal death.In this study,we determined the effects of 5-LOX inhibitor zileuton and Cys LT1 antagonist montelukast on neurotoxicity induced by 1-methyl-4-phenylpyridine(MPP+)in an in vitro model of Parkinson disease(PD).METHODS The neurotoxicity of MPP+,a neurotoxin relevant to PD,on the PC12 cells was measured by MTT assay,lactate dehydrogenase(LDH)release and double fluorescence staining with Hoechst/propidiumiodide(PI).The protective effects of 5-LOX inhibitor zileuton and Cys LT1 antagonist montelukast were investigated by the above methods.RESULTS We found that exposure of PC12 cells to MPP+led to a reduced cell viability and an increased level of LDH in a concentration-dependent manner.Pretreatment with zileuton and montelukast significantly attenuated viability loss and LDH release in MPP+-treated PC12 cells.Furthermore,MPP+increasednecrotic cell death in PC12 cells.Administration of montelukast significantly decreased MPP+-induced cell necrosis in PC12 cells.CONCLUSION The 5-LOX inhibitor zileuton and Cys LT1 antagonist montelukast have a neuroprotective effects on MPP+-induced neurotoxicity in PC12 cells.The 5-LOX inhibitor and Cys LT1 antagonist might raise a possibility as potential therapeutic agent for PD and other inflammation-related the central nervous system disorders.
基金supported by National Natural Science Foundation of China(81671188)Zhejiang Provincial Natural Science Foundation of China(LY12H31010)the Key Laboratory of Hangzhou City Project(20090233T12)
文摘OBJECTIVE We have recently reported that cysteinyl leukotriene(Cys LT) signaling plays an important role in microglial interleukin(IL)-1β secretion and subsequent neurotoxicity.The present study aimed to examine microglial morphological changes and the upstream molecular underlying IL^(-1)β production in Cys LT receptor agonist leukotriene D4(LTD4)-treated BV2 microglia in vitro.METHODS Twenty-four hours after murine microglial BV2 cells were stimulated with LTD4(1-100 nmol·L^(-1)),the cell proliferation and morphology were observed.The expression level of cysteinyl aspartate-specific protease 1(CASP1) protein was measured by Western blotin BV2 cells.In addition,BV2 cells were pretreated with or without CysLT1 receptor antagonist montelukast for 1 h and the effects of monte-lukaston LTD4-stimulated microglial activation and CASP1 expression were evaluated.RESULTS The number of BV2 cells had an increasing tendency after 24 h treatment with LTD4,but no significant differences were observed between the control and LTD4-treated cells(P>0.05).Under basal and resting conditions,BV2 microglial cells displayed a ramified morphology.However,LTD4 at 100 nmool·L^(-1) drove microglial morphological changes from a ramified towards an amoeboid shape.The expression of CASP1 protein was significantly upregulated in 100 nmool·L^(-1) LTD4-treated BV2 microglia(P<0.01).Furthermore,pretreatment with CysLT1 receptor antagonist montelukast prevented cell morphological changes and suppressed the increased CASP1 expression in LTD4-treated BV2 cells(P<0.05).CONCLUSION Cys LT receptor agonist LTD4 induces morphological changes and CASP1 expressionin BV2 microglia,which can be inhibited by CysLT1 antagonist.These results suggest the involvement of Cys LT signaling in microglial morphological changes and CASP1 expression.
