Insecticidal activities and active ingredients of Stephania kwangsiensis Lo. were studied for the first time. The results showed that all parts of S. kwangsiensis Lo. had contact activity against brown planthoppers, N...Insecticidal activities and active ingredients of Stephania kwangsiensis Lo. were studied for the first time. The results showed that all parts of S. kwangsiensis Lo. had contact activity against brown planthoppers, Nilaparvata lugens Stal, and the contact activity of methanol extract from root tubers was the highest, with a LD50 value being 1.5794 lag/female. l-roemerine was isolated from root tubers of S. kwangsiensis Lo. and identified, and it was the main active ingredient. l-roemerine had high contact toxicity to brown planthoppers, with a LD50 value being 0.0443 lag/female. Contact toxicity of l-roemerine to brown planthoppers was 7.48 times that of malathion, the convientional chemical insecticide used for controlling brown planthoppers.l-roemerine also had stomach poison activity against brown planthoppers.展开更多
Objective:To determine the destructive ability of oxocrebanine,an anti-breast cancer active compound obtained from Stephania hainanensis H.S.Lo et Y.Tsoong,on microtubule network,and investigate the effect of oxocreba...Objective:To determine the destructive ability of oxocrebanine,an anti-breast cancer active compound obtained from Stephania hainanensis H.S.Lo et Y.Tsoong,on microtubule network,and investigate the effect of oxocrebanine on microtubule network homeostasis at both molecular and cellular levels.Methods:the EBI site competition method and molecular docking method were used to determine the occupation of the microtubule site of oxocrebanine.Western Blot was used to detect the effect of oxocrebanine on microtubule-associated proteins including STAT3,PAK1,CAMK4,and PKA.Results:The results of EBI site competition assay showed that the binding of EBI toβ-Tubulin covalent fusions produced adducts that appeared in regions of lower molecular weight thanβ-tubulin(ctrl 2).Molecular docking results showed that oxocrebanine could occupy the colchicine site of microtubule proteins.As revealed by Western Blot,the expression of STAT3 protein was decreased after MCF-7 cells have been treated with low,medium,and high concentration of oxocrebanine or the positive drug taxol for 48 h(P<0.01).The expression levels of PAK1 and Camk4 proteins aslo showed significant reductions(P<0.05,or P<0.01).Oxocrebanine also decreased the PKA protein in MCF-7 cells compared to the control group(P<0.01).Conclusions:Oxocrebanine,a ligand that binds at the colchicine site of tubulin,perturbs tubulin polymerization and causes mitosis in MCF-7 cells,thus leading to MCF-7 cell death.Oxocrebanine may promote microtubule dynamics through stathmin by inhibiting the expression levels of STAT3,PAK1,Camk4,and PKA proteins in MCF-7 cells.Oxocrebanine interfers with spindle formation,and ultimately causes mitotic catastrophe in MCF-7 cells.展开更多
基金the Natural Science Foundation of Guangdong Province(03683).
文摘Insecticidal activities and active ingredients of Stephania kwangsiensis Lo. were studied for the first time. The results showed that all parts of S. kwangsiensis Lo. had contact activity against brown planthoppers, Nilaparvata lugens Stal, and the contact activity of methanol extract from root tubers was the highest, with a LD50 value being 1.5794 lag/female. l-roemerine was isolated from root tubers of S. kwangsiensis Lo. and identified, and it was the main active ingredient. l-roemerine had high contact toxicity to brown planthoppers, with a LD50 value being 0.0443 lag/female. Contact toxicity of l-roemerine to brown planthoppers was 7.48 times that of malathion, the convientional chemical insecticide used for controlling brown planthoppers.l-roemerine also had stomach poison activity against brown planthoppers.
基金Natural Science Foundation of Hainan Province(No.820RC776)。
文摘Objective:To determine the destructive ability of oxocrebanine,an anti-breast cancer active compound obtained from Stephania hainanensis H.S.Lo et Y.Tsoong,on microtubule network,and investigate the effect of oxocrebanine on microtubule network homeostasis at both molecular and cellular levels.Methods:the EBI site competition method and molecular docking method were used to determine the occupation of the microtubule site of oxocrebanine.Western Blot was used to detect the effect of oxocrebanine on microtubule-associated proteins including STAT3,PAK1,CAMK4,and PKA.Results:The results of EBI site competition assay showed that the binding of EBI toβ-Tubulin covalent fusions produced adducts that appeared in regions of lower molecular weight thanβ-tubulin(ctrl 2).Molecular docking results showed that oxocrebanine could occupy the colchicine site of microtubule proteins.As revealed by Western Blot,the expression of STAT3 protein was decreased after MCF-7 cells have been treated with low,medium,and high concentration of oxocrebanine or the positive drug taxol for 48 h(P<0.01).The expression levels of PAK1 and Camk4 proteins aslo showed significant reductions(P<0.05,or P<0.01).Oxocrebanine also decreased the PKA protein in MCF-7 cells compared to the control group(P<0.01).Conclusions:Oxocrebanine,a ligand that binds at the colchicine site of tubulin,perturbs tubulin polymerization and causes mitosis in MCF-7 cells,thus leading to MCF-7 cell death.Oxocrebanine may promote microtubule dynamics through stathmin by inhibiting the expression levels of STAT3,PAK1,Camk4,and PKA proteins in MCF-7 cells.Oxocrebanine interfers with spindle formation,and ultimately causes mitotic catastrophe in MCF-7 cells.
