Acacetin(5,7-dihydroxy-4′-methoxyflavone), a potential neuroprotective agent, has an inhibitory effect on lipopolysaccharide-induced neuroinflammatory reactions. However, whether acacetin has an effect on inflammator...Acacetin(5,7-dihydroxy-4′-methoxyflavone), a potential neuroprotective agent, has an inhibitory effect on lipopolysaccharide-induced neuroinflammatory reactions. However, whether acacetin has an effect on inflammatory corpuscle 3(NLRP3) after cerebral ischemia-reperfusion injury has not been fully determined. This study used an improved suture method to establish a cerebral ischemia-reperfusion injury model in C57BL/6 mice. After ischemia with middle cerebral artery occlusion for 1 hour, reperfusion with intraperitoneal injection of 25 mg/kg of acacetin(acacetin group) or an equal volume of saline(0.1 mL/10 g, middle cerebral artery occlusion group) was used to investigate the effect of acacetin on cerebral ischemia-reperfusion injury. Infarct volume and neurological function scores were determined by 2,3,5-triphenyltetrazolium chloride staining and the Zea-Longa scoring method. Compared with the middle cerebral artery occlusion group, neurological function scores and cerebral infarction volumes were significantly reduced in the acacetin group. To understand the effect of acacetin on microglia-mediated inflammatory response after cerebral ischemia-reperfusion injury, immunohistochemistry for the microglia marker calcium adapter protein ionized calcium-binding adaptor molecule 1(Iba1) was examined in the hippocampus of ischemic brain tissue. In addition, tumor necrosis factor-α, interleukin-1β, and interleukin-6 expression in ischemic brain tissue of mice was quantified by enzyme-linked immunosorbent assay. Expression of Iba1, tumor necrosis factor-α, interleukin-1β and interleukin-6 was significantly lower in the acacetin group compared with the middle cerebral artery occlusion group. Western blot assay results showed that expression of Toll-like receptor 4, nuclear factor kappa B, NLRP3, procaspase-1, caspase-1, pro-interleukin-1β, and interleukin-1β were significantly lower in the acacetin group compared with the middle cerebral artery occlusion group. Our findings indicate that acacetin has a protective effect on cerebral ischemia-reperfusion injury, and its mechanism of action is associated with inhibition of microglia-mediated inflammation and the NLRP3 signaling pathway.展开更多
Methicillin-restitant Staphylococcus aureus (MRSA) is very dangerous bacteria and one of the most feared nosocomial germs. In this study, acacetin was evaluated against 20 clinical isolates of MRSA, either alone or in...Methicillin-restitant Staphylococcus aureus (MRSA) is very dangerous bacteria and one of the most feared nosocomial germs. In this study, acacetin was evaluated against 20 clinical isolates of MRSA, either alone or in combination with antibiotics. The acacetin exhibited a good activity against isolates MRSA with MICs/MBCs ranged between 10-80/20-160 μg/mL, for ampicillin 64-1024/128-2048 μg/mL, and for oxacillin 8-32/16-64 μg/mL. The combination of acacetin plus oxacillin or ampicillin was reduced by ≥4-fold against isolates MRSA tested, evidencing a synergistic effect as defined by a FICI of ≤0.5. Furthermore, a time-kill study evaluating the growth of the tested bacteria was completely attenuated after 2-5 h of treatment with the 1/2 MIC of acacetin, regardless of whether it was administered alone or with oxacillin (1/2 MIC) or ampicillin (1/2 MIC). In conclusion, acacetin exerted synergistic effects when administered with oxacillin or ampicillin and the antibacterial activity and resistant regulation of acacetin against clinical isolates of MRSA might be useful in controlling MRSA infections.展开更多
Objective:To explore the glucuronic acid metabolism of acacetin in human liver and intestinal microsomes to better characterize human uridine 5'-diphospho (UDP)-glucuronosyltransferase (UGT) isoforms.In addition,i...Objective:To explore the glucuronic acid metabolism of acacetin in human liver and intestinal microsomes to better characterize human uridine 5'-diphospho (UDP)-glucuronosyltransferase (UGT) isoforms.In addition,interspecies comparisons were performed to identify the most appropriate experimental animal model for an in vivo study.Methods:Liquid chromatography tandem mass spectrometry (LC-MS/MS) and nuclear magnetic resonance (NMR) were used to confirm the successful biosynthesis of acacetin-7-O-glucuronide.Human isoforms of UGT and isozyme-specific chemical inhibitors were used for recombinant assays.Acacetin glucuronidation kinetics were assessed by combining acacetin with recombinant human UGT isoforms or with microsomes from humans or experimental animals.Kinetic differences between species were assessed in vitro using the same approach.Results:We identified multiple UGT isoforms that facilitated acacetin glucuronidation,and found that UGT1A1 was the major isoform that catalyzed this process.Acacetin-7-O-glucuronide formation exhibited clear substrate inhibition kinetics when combined with recombinant UGTs or with liver/intestinal microsomes derived from humans,monkeys,rats,mice,dogs,or pigs.Intrinsic metabolic clearance values of human intestinal microsomes were two-fold greater than those of human liver microsomes.Among the evaluated species,the Km value of dog microsomes (0.86 μM) was greatest in acacetin glucuronidation,while mice exhibited the highest CLint value,5.05 mL/min/mg.The CLint values of microsomes derived from monkeys and minipigs were 1.99 mL/min/mg and 2.12 mL/min/mg,respectively,exhibiting similar intrinsic metabolic clearance activity to that observed in humans.Conclusion:Monkey may represent a suitable model for experimental studies of acacetin pharmacokinetics owing to a high sequence homology of UGT1A1 and similar UGT1A1 glucuronidation activity to humans.展开更多
Objective:To investigate the effect of acacetin on flagellin induced NLRC4 inflammasome activation in mouse bone marrow-derived macrophages(BMDMs).Methods:Mouse BMDMs were divided into control group,LPS group,LPS+flag...Objective:To investigate the effect of acacetin on flagellin induced NLRC4 inflammasome activation in mouse bone marrow-derived macrophages(BMDMs).Methods:Mouse BMDMs were divided into control group,LPS group,LPS+flagellin group and LPS+acacetin+flagellin group.All groups were added with complete medium,then primed with LPS(50 ng/mL)for 3 hrs except the control group,whereafter,LPS+flagellin group was treated with flagellin(10μmol/L)for 0.5 hr and LPS+acacetin+flagellin group was treated with acacetin(10μmol/L)for 0.5 hr following by flagellin(10μmol/L)for 0.5 hr.Pro-caspase-1,pro-IL-1βin cell lysate and caspase-1,IL-1βin supernatant were detected by Western blot(WB).IL-1β,IL-18 and TNF-αin supernatant were measured by enzyme-linked immunosorbent assay(ELISA).And the activity of LDH in supernatant was assessed by LDH test kit.Results:Compared with the control group,in LPS+flagellin group,the expression of caspase-1,IL-1βprotein in supernatant were significantly increased(all P-values<0.05),but the differences of the expression of pro-caspase-1 and pro-IL-1βprotein in cell lysate were not significant.Compared with LPS+flagellin group,in LPS+acacetin+flagellin group,the expression of caspase-1,IL-1βprotein in supernatant were significantly reduced(all P-values<0.05),while the differences of the expression of pro-caspase-1 and pro-IL-1βprotein in cell lysate were not significant.ELISA showed that compared with the control group,the levels of IL-1β,IL-18,and TNF-αand the activity of LDH in supernatant of LPS+flagellin group were significantly increased(all P-values<0.05).Compared with LPS+flagellin group,in LPS+Acacetin+flagellin group,the level of IL-1βin supernatant was significantly decreased(P<0.05),meanwhile,the decreases of the levels IL-18,TNF-αand the activity of LDH were not significant.Conclusions:We found that Acacetin can effectively inhibit flagellin induced NLRC4 inflammasome activation and reduce cell damage in mouse BMDMs.展开更多
BACKGROUND Helicobacter pylori(H.pylori)infection can cause extensive apoptosis of gastric epithelial cells,serving as a critical catalyst in the progression from chronic gastritis,gastrointestinal metaplasia,and atyp...BACKGROUND Helicobacter pylori(H.pylori)infection can cause extensive apoptosis of gastric epithelial cells,serving as a critical catalyst in the progression from chronic gastritis,gastrointestinal metaplasia,and atypical gastric hyperplasia to gastric carcinoma.Prompt eradication of H.pylori is paramount for ameliorating the pathophysiological conditions associated with chronic inflammation of the gastric mucosa and the primary prevention of gastric cancer.Acacetin,which has multifaceted pharmacological activities such as anti-cancer,anti-inflammatory,and antioxidative properties,has been extensively investigated across various domains.Nevertheless,the impact and underlying mechanisms of action of acacetin on H.pylori-infected gastric mucosal epithelial cells remain unclear.AIM To explore the defensive effects of acacetin on apoptosis in H.pylori-infected GES-1 cells and to investigate the underlying mechanisms.METHODS GES-1 cells were treated with H.pylori and acacetin in vitro.Cell viability was assessed using the CCK-8 assay,cell mortality rate via lactate dehydrogenase assay,alterations in cell migration and healing capacities through the wound healing assay,rates of apoptosis via flow cytometry and TUNEL staining,and expression levels of apoptosis-associated proteins through western blot analysis.RESULTS H.pylori infection led to decreased GES-1 cell viability,increased cell mortality,suppressed cell migration,increased rate of apoptosis,increased expressions of Bax and cle-caspase3,and decreased Bcl-2 expression.Conversely,acacetin treatment enhanced cell viability,mitigated apoptosis induced by H.pylori infection,and modulated the expression of apoptosis-regulatory proteins by upregulating Bcl-2 and downregulating Bax and cleaved caspase-3.CONCLUSION Acacetin significantly improved GES-1 cell viability and inhibited apoptosis in H.pylori-infected GES-1 cells,thereby exerting a protective effect on gastric mucosal epithelial cells.展开更多
基金supported by the Natural Science Foundation of Xinjiang Uygur Autonomous Region of China,No.2016D01C120(to JB)
文摘Acacetin(5,7-dihydroxy-4′-methoxyflavone), a potential neuroprotective agent, has an inhibitory effect on lipopolysaccharide-induced neuroinflammatory reactions. However, whether acacetin has an effect on inflammatory corpuscle 3(NLRP3) after cerebral ischemia-reperfusion injury has not been fully determined. This study used an improved suture method to establish a cerebral ischemia-reperfusion injury model in C57BL/6 mice. After ischemia with middle cerebral artery occlusion for 1 hour, reperfusion with intraperitoneal injection of 25 mg/kg of acacetin(acacetin group) or an equal volume of saline(0.1 mL/10 g, middle cerebral artery occlusion group) was used to investigate the effect of acacetin on cerebral ischemia-reperfusion injury. Infarct volume and neurological function scores were determined by 2,3,5-triphenyltetrazolium chloride staining and the Zea-Longa scoring method. Compared with the middle cerebral artery occlusion group, neurological function scores and cerebral infarction volumes were significantly reduced in the acacetin group. To understand the effect of acacetin on microglia-mediated inflammatory response after cerebral ischemia-reperfusion injury, immunohistochemistry for the microglia marker calcium adapter protein ionized calcium-binding adaptor molecule 1(Iba1) was examined in the hippocampus of ischemic brain tissue. In addition, tumor necrosis factor-α, interleukin-1β, and interleukin-6 expression in ischemic brain tissue of mice was quantified by enzyme-linked immunosorbent assay. Expression of Iba1, tumor necrosis factor-α, interleukin-1β and interleukin-6 was significantly lower in the acacetin group compared with the middle cerebral artery occlusion group. Western blot assay results showed that expression of Toll-like receptor 4, nuclear factor kappa B, NLRP3, procaspase-1, caspase-1, pro-interleukin-1β, and interleukin-1β were significantly lower in the acacetin group compared with the middle cerebral artery occlusion group. Our findings indicate that acacetin has a protective effect on cerebral ischemia-reperfusion injury, and its mechanism of action is associated with inhibition of microglia-mediated inflammation and the NLRP3 signaling pathway.
文摘Methicillin-restitant Staphylococcus aureus (MRSA) is very dangerous bacteria and one of the most feared nosocomial germs. In this study, acacetin was evaluated against 20 clinical isolates of MRSA, either alone or in combination with antibiotics. The acacetin exhibited a good activity against isolates MRSA with MICs/MBCs ranged between 10-80/20-160 μg/mL, for ampicillin 64-1024/128-2048 μg/mL, and for oxacillin 8-32/16-64 μg/mL. The combination of acacetin plus oxacillin or ampicillin was reduced by ≥4-fold against isolates MRSA tested, evidencing a synergistic effect as defined by a FICI of ≤0.5. Furthermore, a time-kill study evaluating the growth of the tested bacteria was completely attenuated after 2-5 h of treatment with the 1/2 MIC of acacetin, regardless of whether it was administered alone or with oxacillin (1/2 MIC) or ampicillin (1/2 MIC). In conclusion, acacetin exerted synergistic effects when administered with oxacillin or ampicillin and the antibacterial activity and resistant regulation of acacetin against clinical isolates of MRSA might be useful in controlling MRSA infections.
基金the National Natural Science Foundation of China(81473800).
文摘Objective:To explore the glucuronic acid metabolism of acacetin in human liver and intestinal microsomes to better characterize human uridine 5'-diphospho (UDP)-glucuronosyltransferase (UGT) isoforms.In addition,interspecies comparisons were performed to identify the most appropriate experimental animal model for an in vivo study.Methods:Liquid chromatography tandem mass spectrometry (LC-MS/MS) and nuclear magnetic resonance (NMR) were used to confirm the successful biosynthesis of acacetin-7-O-glucuronide.Human isoforms of UGT and isozyme-specific chemical inhibitors were used for recombinant assays.Acacetin glucuronidation kinetics were assessed by combining acacetin with recombinant human UGT isoforms or with microsomes from humans or experimental animals.Kinetic differences between species were assessed in vitro using the same approach.Results:We identified multiple UGT isoforms that facilitated acacetin glucuronidation,and found that UGT1A1 was the major isoform that catalyzed this process.Acacetin-7-O-glucuronide formation exhibited clear substrate inhibition kinetics when combined with recombinant UGTs or with liver/intestinal microsomes derived from humans,monkeys,rats,mice,dogs,or pigs.Intrinsic metabolic clearance values of human intestinal microsomes were two-fold greater than those of human liver microsomes.Among the evaluated species,the Km value of dog microsomes (0.86 μM) was greatest in acacetin glucuronidation,while mice exhibited the highest CLint value,5.05 mL/min/mg.The CLint values of microsomes derived from monkeys and minipigs were 1.99 mL/min/mg and 2.12 mL/min/mg,respectively,exhibiting similar intrinsic metabolic clearance activity to that observed in humans.Conclusion:Monkey may represent a suitable model for experimental studies of acacetin pharmacokinetics owing to a high sequence homology of UGT1A1 and similar UGT1A1 glucuronidation activity to humans.
基金Xinjiang Uygur Autonomous Region Natural Science Foundation(No.2020D01C095)Xinjiang Uygur Autonomous Region Outstanding Young Scientist and Technological Talents Training Project(No.2020Q046)Xinjiang Uygur Autonomous Region People's Hospital In-Hospital Project(No.20210102)。
文摘Objective:To investigate the effect of acacetin on flagellin induced NLRC4 inflammasome activation in mouse bone marrow-derived macrophages(BMDMs).Methods:Mouse BMDMs were divided into control group,LPS group,LPS+flagellin group and LPS+acacetin+flagellin group.All groups were added with complete medium,then primed with LPS(50 ng/mL)for 3 hrs except the control group,whereafter,LPS+flagellin group was treated with flagellin(10μmol/L)for 0.5 hr and LPS+acacetin+flagellin group was treated with acacetin(10μmol/L)for 0.5 hr following by flagellin(10μmol/L)for 0.5 hr.Pro-caspase-1,pro-IL-1βin cell lysate and caspase-1,IL-1βin supernatant were detected by Western blot(WB).IL-1β,IL-18 and TNF-αin supernatant were measured by enzyme-linked immunosorbent assay(ELISA).And the activity of LDH in supernatant was assessed by LDH test kit.Results:Compared with the control group,in LPS+flagellin group,the expression of caspase-1,IL-1βprotein in supernatant were significantly increased(all P-values<0.05),but the differences of the expression of pro-caspase-1 and pro-IL-1βprotein in cell lysate were not significant.Compared with LPS+flagellin group,in LPS+acacetin+flagellin group,the expression of caspase-1,IL-1βprotein in supernatant were significantly reduced(all P-values<0.05),while the differences of the expression of pro-caspase-1 and pro-IL-1βprotein in cell lysate were not significant.ELISA showed that compared with the control group,the levels of IL-1β,IL-18,and TNF-αand the activity of LDH in supernatant of LPS+flagellin group were significantly increased(all P-values<0.05).Compared with LPS+flagellin group,in LPS+Acacetin+flagellin group,the level of IL-1βin supernatant was significantly decreased(P<0.05),meanwhile,the decreases of the levels IL-18,TNF-αand the activity of LDH were not significant.Conclusions:We found that Acacetin can effectively inhibit flagellin induced NLRC4 inflammasome activation and reduce cell damage in mouse BMDMs.
基金Supported by the Doctoral Research Initiation Fund of Affiliated Hospital of Southwest Medical University,No.21037.
文摘BACKGROUND Helicobacter pylori(H.pylori)infection can cause extensive apoptosis of gastric epithelial cells,serving as a critical catalyst in the progression from chronic gastritis,gastrointestinal metaplasia,and atypical gastric hyperplasia to gastric carcinoma.Prompt eradication of H.pylori is paramount for ameliorating the pathophysiological conditions associated with chronic inflammation of the gastric mucosa and the primary prevention of gastric cancer.Acacetin,which has multifaceted pharmacological activities such as anti-cancer,anti-inflammatory,and antioxidative properties,has been extensively investigated across various domains.Nevertheless,the impact and underlying mechanisms of action of acacetin on H.pylori-infected gastric mucosal epithelial cells remain unclear.AIM To explore the defensive effects of acacetin on apoptosis in H.pylori-infected GES-1 cells and to investigate the underlying mechanisms.METHODS GES-1 cells were treated with H.pylori and acacetin in vitro.Cell viability was assessed using the CCK-8 assay,cell mortality rate via lactate dehydrogenase assay,alterations in cell migration and healing capacities through the wound healing assay,rates of apoptosis via flow cytometry and TUNEL staining,and expression levels of apoptosis-associated proteins through western blot analysis.RESULTS H.pylori infection led to decreased GES-1 cell viability,increased cell mortality,suppressed cell migration,increased rate of apoptosis,increased expressions of Bax and cle-caspase3,and decreased Bcl-2 expression.Conversely,acacetin treatment enhanced cell viability,mitigated apoptosis induced by H.pylori infection,and modulated the expression of apoptosis-regulatory proteins by upregulating Bcl-2 and downregulating Bax and cleaved caspase-3.CONCLUSION Acacetin significantly improved GES-1 cell viability and inhibited apoptosis in H.pylori-infected GES-1 cells,thereby exerting a protective effect on gastric mucosal epithelial cells.
