AIM:To investigate the effects of quercetin on diabetic retinopathy(DR)and its association with nucleotidebinding oligomerization domain-like receptors 3(NLRP3)inflammasome and autophagy using retinal endothelial cell...AIM:To investigate the effects of quercetin on diabetic retinopathy(DR)and its association with nucleotidebinding oligomerization domain-like receptors 3(NLRP3)inflammasome and autophagy using retinal endothelial cell as an experimental model.METHODS:Human retinal microvascular endothelial cells(HRMECs)were cultured in vitro and assigned into the control group,high-glucose(HG)group,and HG+different concentrations of quercetin groups.Cellular viability,migration,and tube formation in these groups was detected by MTT,transwell and matrigel assay,respectively.Expressions of NLRP3,apoptosis-associated speck-like protein(ASC),cysteiny aspartate-specific protease-1(Caspase-1)as well as microtubule-related protein 1 light chain 3(LC3)and Beclin-1 were detected by Western blotting.Expressions of IL-1β and IL-18 were detected by ELISA and cellular autophagy was detected by Cyto-ID■ autophagy detection kit.RESULTS:Under an HG condition,the viability,migration,tube formation of HRMECs,and the protein expressions of NLRP3,ASC,Caspase-1,IL-1β,IL-18,LC3,and Beclin-1 as well as autophagy were all increased.Quercetin inhibited angiogenesis of HRMECs as well as the expressions of NLRP3,ASC,Caspase-1,IL-1β,IL-18,LC3,Beclin-1,and autophagy of HRMECs under a HG condition.The inhibitory effects of quercetin on angiogenesis,NLRP3 inflammasome and autophagy increased with the increase of its concentration.CONCLUSION:The therapeutic potential of quercetin in retinal neovascularization of DR,and inhibition of NLRP3 inflammasome and autophagy signaling pathway may be involved.展开更多
To explore the effect of quercetin on the proliferation and apoptosis of HeLa cells, HeLa cells were incubated with quercetin at different concentrations. Cell viability was evaluated by MTT assay, cell apoptosis was ...To explore the effect of quercetin on the proliferation and apoptosis of HeLa cells, HeLa cells were incubated with quercetin at different concentrations. Cell viability was evaluated by MTT assay, cell apoptosis was detected by Annexin- V/PI double labeled cytometry and DNA ladder assay. Cell cycle was flow cytometrically determined and the morphological changes of the cells were ob- served under a fluorescence microscope after Hoechst 33258 staining and the apoptosis-related pro- teins in the HeLa cells were assessed by Western blotting. The results showed that quercetin signifi- cantly inhibited the growth of HeLa cells and induced obvious apoptosis in vitro in a time- and dose-dependent manner. Moreover, quercetin induced apoptosis of HeLa cells in cell cycle-dependent manner because quercetin could induce arrest of HeLa cells at G0/G1 phase. Quercetin treatment down-regulated the expression of the PI3K and p-Akt. In addition, quercetin could down-regulate ex- pression of bcl-2, up-regulate Bax, but exerted no effect on the overall expression of Akt. We are led to conclude that quercetin induces apoptosis via PI3k/Akt pathways, and quercetin has potential to be used as an anti-tumor agent against human cervix oancer.展开更多
Liver cancer is the seventh most common malignant tumor in the world and is the second highest cause of death due to cancer.Quercetin,a flavonoid with low toxicity,widely exists in various fruits and vegetables.It has...Liver cancer is the seventh most common malignant tumor in the world and is the second highest cause of death due to cancer.Quercetin,a flavonoid with low toxicity,widely exists in various fruits and vegetables.It has the potential to be a therapeutic agent against various cancers.This study aimed to demonstrate the anti-tumor effect of quercetin on HepG2 cells.Quercetin suppressed the HepG2 cell proliferation in a dose-dependent manner in cell viability assay.Induction of cell apoptosis was confirmed by apoptotic cells population(sub-G1 peak)detected by flow cytometer.A decrease in mitochondrial membrane potential and caspase-3 activation were also demonstrated in this study.Furthermore,quercetin induced HepG2 cell apoptosis through ROS-mediated phosphorylated ataxia-telangiectasia mutated,c-Jun Nterminal kinases,signal transducer,and activator of transcription 3(STAT-3),and Bax signaling pathways.These results suggest that quercetin has the potential to become an effective drug against the tumor.展开更多
Delonix elata L.is a Ceasalpinaceae species and is traditionally used in India for treatment of skin diseases,liver diseases and rheumatic problems.However,systematic evaluation of its wound healing activity is lackin...Delonix elata L.is a Ceasalpinaceae species and is traditionally used in India for treatment of skin diseases,liver diseases and rheumatic problems.However,systematic evaluation of its wound healing activity is lacking.Thus,in the present study,we aimed to assess the wound healing activity of D.elata stem bark extract(DSE) and its isolated constituent quercetin-3-rhamnopyranosyl-(1-6) glucopyranoside(QRPG) in rats.The formulations effects on wound healing were assessed by the wound contraction rate,epithelialization period,tensile strength,content of the hydroxyproline,hexosamine and uronic acid in granulation tissue,histopathological studies and Col 1 α(I) expression level in wound tissue by reverse transcription polymerase chain reaction(RT-PCR) study.The topical application of DSE ointment caused faster epithelialization,significant wound contraction(100%),and better tensile strength(710.5 ± 10.5 g/cm^2),while QRPG showed wound epithelialization with 98.2%contraction,better than that of the control group(78.18%).The biochemical analysis of granulation tissue revealed that DSE and QRPG significantly increased hydroxyproline,hexosamine and uronic acid content.A significant increase in the expression of Col 1 α(I) was observed in the wound tissue of DSE and QRPG treated rats.DSE and QRPG were shown to enhance wound healing by increasing collagen synthesis through upregulation of Col 1 α(I),thus validating ethnomedicinal uses.展开更多
The core of the natural product chemistry laboratory is isolation secondary metabolit</span><span style="font-family:Verdana;">e</span><span style="font-family:""><s...The core of the natural product chemistry laboratory is isolation secondary metabolit</span><span style="font-family:Verdana;">e</span><span style="font-family:""><span style="font-family:Verdana;">s. One of the potential secondary metabolites for isolation in the natural product chemistry laboratory is routine (quercetin-3-O-glycosides). Routine (Quercetin-3-O-glycoside) has been isolated from ethanol extract of rubber cassava leaves (</span><i><span style="font-family:Verdana;">Manihot glaziovii </span></i><span style="font-family:Verdana;">MA). Isolation was done by maceration and recrystallization. The isolation method used in this study is complemented by the isolation method published. The isolated (Quercetin-3-O-glycoside) routine using this method obtained a yield of 0.118% of the total dried leaf extract. The routine (Quercetin-3-O-glycoside) was identified using a standard routine. Routine can be further utilized in the world of medicine as an amplifier of capillary structure, reducing the permeability and fragility of blood vessels.展开更多
目的 :研究南葶苈子中槲皮素 3 O β D 葡萄糖 7 O β D 龙胆双糖苷的含量测定方法 ,建立南葶苈子药材质量标准。方法 :采用反相高效液相色谱法 ,以自制标准品作对照 ,对南葶苈子药材中主要有效成分槲皮素 3 O β D 葡萄糖 7 O β D...目的 :研究南葶苈子中槲皮素 3 O β D 葡萄糖 7 O β D 龙胆双糖苷的含量测定方法 ,建立南葶苈子药材质量标准。方法 :采用反相高效液相色谱法 ,以自制标准品作对照 ,对南葶苈子药材中主要有效成分槲皮素 3 O β D 葡萄糖 7 O β D 龙胆双糖苷进行了含量测定。 结果 :回收率为 99.78% ,RSD为 2 .4 %。结论 :该方法可用于南葶苈子药材的质量控制。展开更多
The synthetic route of 3’-amino carboxylate hydrochloride of quercetin is improved.Using benzyl bromide to partly protect the hydroxyl groups,the protected quercetin then react with a series of Boc protected amino ac...The synthetic route of 3’-amino carboxylate hydrochloride of quercetin is improved.Using benzyl bromide to partly protect the hydroxyl groups,the protected quercetin then react with a series of Boc protected amino acids to afford the 3’-amino carboxylate,hydrogenised and treated with HCl(g),a series of 3’-amino carboxylate hydrochloride of quercetin are synthesized in good yields.The structures of these compounds are confirmed by means of their m.p.,mass spectra and 1H NMR.展开更多
基金Supported by the National Natural Science Foundation of China(No.81500726)the Matching Funds of the National Natural Science Foundation of China(No.XYFYPT-2020-01)。
文摘AIM:To investigate the effects of quercetin on diabetic retinopathy(DR)and its association with nucleotidebinding oligomerization domain-like receptors 3(NLRP3)inflammasome and autophagy using retinal endothelial cell as an experimental model.METHODS:Human retinal microvascular endothelial cells(HRMECs)were cultured in vitro and assigned into the control group,high-glucose(HG)group,and HG+different concentrations of quercetin groups.Cellular viability,migration,and tube formation in these groups was detected by MTT,transwell and matrigel assay,respectively.Expressions of NLRP3,apoptosis-associated speck-like protein(ASC),cysteiny aspartate-specific protease-1(Caspase-1)as well as microtubule-related protein 1 light chain 3(LC3)and Beclin-1 were detected by Western blotting.Expressions of IL-1β and IL-18 were detected by ELISA and cellular autophagy was detected by Cyto-ID■ autophagy detection kit.RESULTS:Under an HG condition,the viability,migration,tube formation of HRMECs,and the protein expressions of NLRP3,ASC,Caspase-1,IL-1β,IL-18,LC3,and Beclin-1 as well as autophagy were all increased.Quercetin inhibited angiogenesis of HRMECs as well as the expressions of NLRP3,ASC,Caspase-1,IL-1β,IL-18,LC3,Beclin-1,and autophagy of HRMECs under a HG condition.The inhibitory effects of quercetin on angiogenesis,NLRP3 inflammasome and autophagy increased with the increase of its concentration.CONCLUSION:The therapeutic potential of quercetin in retinal neovascularization of DR,and inhibition of NLRP3 inflammasome and autophagy signaling pathway may be involved.
基金supported by the National Natural Science Foundation of China(No.81071663)
文摘To explore the effect of quercetin on the proliferation and apoptosis of HeLa cells, HeLa cells were incubated with quercetin at different concentrations. Cell viability was evaluated by MTT assay, cell apoptosis was detected by Annexin- V/PI double labeled cytometry and DNA ladder assay. Cell cycle was flow cytometrically determined and the morphological changes of the cells were ob- served under a fluorescence microscope after Hoechst 33258 staining and the apoptosis-related pro- teins in the HeLa cells were assessed by Western blotting. The results showed that quercetin signifi- cantly inhibited the growth of HeLa cells and induced obvious apoptosis in vitro in a time- and dose-dependent manner. Moreover, quercetin induced apoptosis of HeLa cells in cell cycle-dependent manner because quercetin could induce arrest of HeLa cells at G0/G1 phase. Quercetin treatment down-regulated the expression of the PI3K and p-Akt. In addition, quercetin could down-regulate ex- pression of bcl-2, up-regulate Bax, but exerted no effect on the overall expression of Akt. We are led to conclude that quercetin induces apoptosis via PI3k/Akt pathways, and quercetin has potential to be used as an anti-tumor agent against human cervix oancer.
基金This work was supported by theGuangdong Natural Science Foundation(2020A1515110648)the Open Fund of Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and Applications(2020A03)+2 种基金the Technology Planning Project of Guangzhou(202102010202 and 202201020655)the Open Project of Guangdong Key Laboratory of Marine Materia Medica(LMM2020-7)the Guangzhou Medical University Students’Science and Technology Innovation Project(02-408-2203-2079,2021AEK119,2021AEK122,2021AEK125 and 2021AEK128).
文摘Liver cancer is the seventh most common malignant tumor in the world and is the second highest cause of death due to cancer.Quercetin,a flavonoid with low toxicity,widely exists in various fruits and vegetables.It has the potential to be a therapeutic agent against various cancers.This study aimed to demonstrate the anti-tumor effect of quercetin on HepG2 cells.Quercetin suppressed the HepG2 cell proliferation in a dose-dependent manner in cell viability assay.Induction of cell apoptosis was confirmed by apoptotic cells population(sub-G1 peak)detected by flow cytometer.A decrease in mitochondrial membrane potential and caspase-3 activation were also demonstrated in this study.Furthermore,quercetin induced HepG2 cell apoptosis through ROS-mediated phosphorylated ataxia-telangiectasia mutated,c-Jun Nterminal kinases,signal transducer,and activator of transcription 3(STAT-3),and Bax signaling pathways.These results suggest that quercetin has the potential to become an effective drug against the tumor.
基金partially supported by the Department of Biotechnology,New Delhi,India(Grant no.BT/PR11505/SPD/24/337/2008BT/PR9128/INF/22/190/2013)
文摘Delonix elata L.is a Ceasalpinaceae species and is traditionally used in India for treatment of skin diseases,liver diseases and rheumatic problems.However,systematic evaluation of its wound healing activity is lacking.Thus,in the present study,we aimed to assess the wound healing activity of D.elata stem bark extract(DSE) and its isolated constituent quercetin-3-rhamnopyranosyl-(1-6) glucopyranoside(QRPG) in rats.The formulations effects on wound healing were assessed by the wound contraction rate,epithelialization period,tensile strength,content of the hydroxyproline,hexosamine and uronic acid in granulation tissue,histopathological studies and Col 1 α(I) expression level in wound tissue by reverse transcription polymerase chain reaction(RT-PCR) study.The topical application of DSE ointment caused faster epithelialization,significant wound contraction(100%),and better tensile strength(710.5 ± 10.5 g/cm^2),while QRPG showed wound epithelialization with 98.2%contraction,better than that of the control group(78.18%).The biochemical analysis of granulation tissue revealed that DSE and QRPG significantly increased hydroxyproline,hexosamine and uronic acid content.A significant increase in the expression of Col 1 α(I) was observed in the wound tissue of DSE and QRPG treated rats.DSE and QRPG were shown to enhance wound healing by increasing collagen synthesis through upregulation of Col 1 α(I),thus validating ethnomedicinal uses.
文摘The core of the natural product chemistry laboratory is isolation secondary metabolit</span><span style="font-family:Verdana;">e</span><span style="font-family:""><span style="font-family:Verdana;">s. One of the potential secondary metabolites for isolation in the natural product chemistry laboratory is routine (quercetin-3-O-glycosides). Routine (Quercetin-3-O-glycoside) has been isolated from ethanol extract of rubber cassava leaves (</span><i><span style="font-family:Verdana;">Manihot glaziovii </span></i><span style="font-family:Verdana;">MA). Isolation was done by maceration and recrystallization. The isolation method used in this study is complemented by the isolation method published. The isolated (Quercetin-3-O-glycoside) routine using this method obtained a yield of 0.118% of the total dried leaf extract. The routine (Quercetin-3-O-glycoside) was identified using a standard routine. Routine can be further utilized in the world of medicine as an amplifier of capillary structure, reducing the permeability and fragility of blood vessels.
文摘目的 :研究南葶苈子中槲皮素 3 O β D 葡萄糖 7 O β D 龙胆双糖苷的含量测定方法 ,建立南葶苈子药材质量标准。方法 :采用反相高效液相色谱法 ,以自制标准品作对照 ,对南葶苈子药材中主要有效成分槲皮素 3 O β D 葡萄糖 7 O β D 龙胆双糖苷进行了含量测定。 结果 :回收率为 99.78% ,RSD为 2 .4 %。结论 :该方法可用于南葶苈子药材的质量控制。
文摘The synthetic route of 3’-amino carboxylate hydrochloride of quercetin is improved.Using benzyl bromide to partly protect the hydroxyl groups,the protected quercetin then react with a series of Boc protected amino acids to afford the 3’-amino carboxylate,hydrogenised and treated with HCl(g),a series of 3’-amino carboxylate hydrochloride of quercetin are synthesized in good yields.The structures of these compounds are confirmed by means of their m.p.,mass spectra and 1H NMR.
