OBJECTIVE To investigate the role of transient receptor potential melastatin 2(TRPM2),a calcium-permeable non-selective cation channel which acts as an oxidative stress sensor,in mediating the production of pro-inflam...OBJECTIVE To investigate the role of transient receptor potential melastatin 2(TRPM2),a calcium-permeable non-selective cation channel which acts as an oxidative stress sensor,in mediating the production of pro-inflammatory IL-1βin high glucose condition.METHODS Human pro-monocytic leukemia cell U937 was purchased from ATCC and cultured in RPMI 1640(Life Technologies).Prior to high glucose(HG)stimulation,U937 cells were cultured in medium with glucose 5.5mmol·L-1 for 48 h.The cells were then incubated in high glucose concentration(30mmol·L-1)or mannitol(30mmol·L-1)for 48 h.The protein expression of TRPM2 and the production of human IL-1β were evaluated by ELISA.TRPM2 inhibitors(DPQ and AMP)and TRPM2 siRNAs were employed to further investigate the role of TRPM2 in HG-induced IL-1β production.RESULTS The TRPM2 protein expression was significantly up-regulated by 2-folds in U937 cells after the treatment of high glucose(30mmol·L-1 for 48h)(P<0.01).The production of IL-1β in U937 was also significantly increased by HG treatment and was time-and dose-dependent(10,20 or 30mmol·L-1 glucose for 24,48 or 72h)(P<0.01).The HG-induced IL-1β production in U937 could be abolished by using TRPM2 inhibitors DPQ(100μmol·L-1 for 45min)and AMP(100μmol·L-1 for 45 min)as well as by the transfection of TRPM2siRNAs(60nmol·L-1).CONCLUSION High glucose condition(such as in diabetes)might mediate pro-inflammatory environments via the modulation of TRPM2 channels on immune cells.展开更多
OBJECTIVE The present study examined the potential of flavonoids in reducing airway inflammation and determined the structure activity relationships(SAR),if present,for their anti-inflammatory effects.METHODS Seventee...OBJECTIVE The present study examined the potential of flavonoids in reducing airway inflammation and determined the structure activity relationships(SAR),if present,for their anti-inflammatory effects.METHODS Seventeen flavonoids with different chemical structures were selected for the study.Inflammation was induced in human bronchial epithelial BEAS-2B cells with lipopolysaccharide(LPS).BEAS-2Bcells were incubated with or without different flavonoids(10μmol·L-1)1hbefore treatment with LPS(10μg·mL-1)for 24 h.The viability of the cells after exposure to LPS and/or flavonoids were determined by thiazolyl blue tetrazolium bromide(MTT)assay.The amount of the inflammatory mediators,interleukin(IL)-6,IL-8 and monocyte chemoattractant protein-1(MCP-1),were measured in the supernatants byenzyme-linked immunosorbent assay(ELISA).RESULTS Flavonoids(1to 10μmol·L-1)and LPS(1 to 10μg·mL-1)did not affect the viability of BEAS-2B cells.LPS(10μg·mL-1)significantly stimulated the release of IL-6,IL-8 and MCP-1 in BEAS-2B cells.Among the flavonoids tested,only apigenin,luteolin and genistein(10μmol·L-1)significantly inhibited the release of the inflammatory mediators.CONCLUSION These findings suggested that a hydroxy group at C5 and C7 positions in the A ring,a double bond between C2 and C3 and acarbonyl group at the C4 position in the C ring of the flavonoid might play an important role for their anti-inflammatory effect.The presence of a hydroxy group at C3 position or glycosylation at C3 or C7 position reduces the effectiveness of a flavonoid as an anti-inflammatory agent.展开更多
基金The project supported by Science and Technology Development Fund of Macao SAR(118/2012/A)Research Committee of the University of Macao〔MYRG124(Y1-L3)-ICMS12-HPM〕
文摘OBJECTIVE To investigate the role of transient receptor potential melastatin 2(TRPM2),a calcium-permeable non-selective cation channel which acts as an oxidative stress sensor,in mediating the production of pro-inflammatory IL-1βin high glucose condition.METHODS Human pro-monocytic leukemia cell U937 was purchased from ATCC and cultured in RPMI 1640(Life Technologies).Prior to high glucose(HG)stimulation,U937 cells were cultured in medium with glucose 5.5mmol·L-1 for 48 h.The cells were then incubated in high glucose concentration(30mmol·L-1)or mannitol(30mmol·L-1)for 48 h.The protein expression of TRPM2 and the production of human IL-1β were evaluated by ELISA.TRPM2 inhibitors(DPQ and AMP)and TRPM2 siRNAs were employed to further investigate the role of TRPM2 in HG-induced IL-1β production.RESULTS The TRPM2 protein expression was significantly up-regulated by 2-folds in U937 cells after the treatment of high glucose(30mmol·L-1 for 48h)(P<0.01).The production of IL-1β in U937 was also significantly increased by HG treatment and was time-and dose-dependent(10,20 or 30mmol·L-1 glucose for 24,48 or 72h)(P<0.01).The HG-induced IL-1β production in U937 could be abolished by using TRPM2 inhibitors DPQ(100μmol·L-1 for 45min)and AMP(100μmol·L-1 for 45 min)as well as by the transfection of TRPM2siRNAs(60nmol·L-1).CONCLUSION High glucose condition(such as in diabetes)might mediate pro-inflammatory environments via the modulation of TRPM2 channels on immune cells.
基金The project supported by the Health and Medical Research Fund of the Food and Health Bureau of Hong Kong SAR(11123011)
文摘OBJECTIVE The present study examined the potential of flavonoids in reducing airway inflammation and determined the structure activity relationships(SAR),if present,for their anti-inflammatory effects.METHODS Seventeen flavonoids with different chemical structures were selected for the study.Inflammation was induced in human bronchial epithelial BEAS-2B cells with lipopolysaccharide(LPS).BEAS-2Bcells were incubated with or without different flavonoids(10μmol·L-1)1hbefore treatment with LPS(10μg·mL-1)for 24 h.The viability of the cells after exposure to LPS and/or flavonoids were determined by thiazolyl blue tetrazolium bromide(MTT)assay.The amount of the inflammatory mediators,interleukin(IL)-6,IL-8 and monocyte chemoattractant protein-1(MCP-1),were measured in the supernatants byenzyme-linked immunosorbent assay(ELISA).RESULTS Flavonoids(1to 10μmol·L-1)and LPS(1 to 10μg·mL-1)did not affect the viability of BEAS-2B cells.LPS(10μg·mL-1)significantly stimulated the release of IL-6,IL-8 and MCP-1 in BEAS-2B cells.Among the flavonoids tested,only apigenin,luteolin and genistein(10μmol·L-1)significantly inhibited the release of the inflammatory mediators.CONCLUSION These findings suggested that a hydroxy group at C5 and C7 positions in the A ring,a double bond between C2 and C3 and acarbonyl group at the C4 position in the C ring of the flavonoid might play an important role for their anti-inflammatory effect.The presence of a hydroxy group at C3 position or glycosylation at C3 or C7 position reduces the effectiveness of a flavonoid as an anti-inflammatory agent.
