Two cardenolide glycosides,corotoxigenin 3-0-[β-D-glucopyranosyl-(l→4)-6-deoxy-β-D-glucopyranoside](1)and coroglaucigenin 3-0-[β-D-glucopyranosyl-(l→4)-6-deoxy-β-D-glucopyranoside](2),were isolated from the seed...Two cardenolide glycosides,corotoxigenin 3-0-[β-D-glucopyranosyl-(l→4)-6-deoxy-β-D-glucopyranoside](1)and coroglaucigenin 3-0-[β-D-glucopyranosyl-(l→4)-6-deoxy-β-D-glucopyranoside](2),were isolated from the seed fairs of Asclepias curassavica.The structures of 1-2 were determined based on the combination of the analysis of their MS,NMR spectroscopic data and acid hydrolysis.The inhibitory effects of compounds 1 and 2 on human colorectal carcinoma cells(HCT116),non-small cell lung carcinoma cells(A549)and hepatic cancer cells(SMMC-7721)were evaluated.The results showed that both compounds 1 and 2 significantly inhibited the viability,proliferation,and migration of A549,HCT116 and SMMC-7721 cells,suggesting that compounds 1 and 2 can be applied in the treatment of lung,colon and liver cancers in clinical practice.This study may not only provide a scientific basis for clarifying the active ingredients in A.curassavica,but also help to understand its antitumor activity,which can promote the application of A.curassavica in clinical treatment of various cancers.展开更多
We review the postulated threatening processes that may have affected the de- cline in the eastern population of the monarch butterfly, Danausplexippus L. （Lepidoptera： Nymphalidae）, in North America. Although ther...We review the postulated threatening processes that may have affected the de- cline in the eastern population of the monarch butterfly, Danausplexippus L. （Lepidoptera： Nymphalidae）, in North America. Although there are likely multiple contributing factors, such as climate and resource-related effects on breeding, migrating, and overwintering populations, the key landscape-level change appears to be associated with the widespread use of genetically modified herbicide resistant crops that have rapidly come to dominate the extensive core summer breeding range. We dismiss misinterpretations of the apparent lack of population change in summer adult count data as logically flawed. Glyphosate-tolerant soybean and maize have enabled the extensive use of this herbicide, generating widespread losses of milkweed （Asclepias spp.）, the only host plants for monarch larvae. Modeling studies that simulate lifetime realized fecundity at a landscape scale, direct counts of milkweeds, and extensive citizen science data across the breeding range suggest that a herbicide-induced, landscape-level reduction in milkweed has precipitated the decline in monarchs. A recovery will likely require a monumental effort for the re-establishment of milkweed resources at a commensurate landscape scale.展开更多
基金supported by the Science and Technology Program of Guangzhou,China(No.201804010083)the National Natural Science Foundation of China(Nos.81720108033 and 81930114)+2 种基金Guangdong Key Laboratory for Translational Cancer Research of Chinese Medicine(No.2018B030322011)the Project of Guangzhou University of Chinese Medicine(No.QNYC20190103)the Project of Traditional Chinese Medicine Bureau of Guangdong Province(No.20211111).
文摘Two cardenolide glycosides,corotoxigenin 3-0-[β-D-glucopyranosyl-(l→4)-6-deoxy-β-D-glucopyranoside](1)and coroglaucigenin 3-0-[β-D-glucopyranosyl-(l→4)-6-deoxy-β-D-glucopyranoside](2),were isolated from the seed fairs of Asclepias curassavica.The structures of 1-2 were determined based on the combination of the analysis of their MS,NMR spectroscopic data and acid hydrolysis.The inhibitory effects of compounds 1 and 2 on human colorectal carcinoma cells(HCT116),non-small cell lung carcinoma cells(A549)and hepatic cancer cells(SMMC-7721)were evaluated.The results showed that both compounds 1 and 2 significantly inhibited the viability,proliferation,and migration of A549,HCT116 and SMMC-7721 cells,suggesting that compounds 1 and 2 can be applied in the treatment of lung,colon and liver cancers in clinical practice.This study may not only provide a scientific basis for clarifying the active ingredients in A.curassavica,but also help to understand its antitumor activity,which can promote the application of A.curassavica in clinical treatment of various cancers.
文摘We review the postulated threatening processes that may have affected the de- cline in the eastern population of the monarch butterfly, Danausplexippus L. （Lepidoptera： Nymphalidae）, in North America. Although there are likely multiple contributing factors, such as climate and resource-related effects on breeding, migrating, and overwintering populations, the key landscape-level change appears to be associated with the widespread use of genetically modified herbicide resistant crops that have rapidly come to dominate the extensive core summer breeding range. We dismiss misinterpretations of the apparent lack of population change in summer adult count data as logically flawed. Glyphosate-tolerant soybean and maize have enabled the extensive use of this herbicide, generating widespread losses of milkweed （Asclepias spp.）, the only host plants for monarch larvae. Modeling studies that simulate lifetime realized fecundity at a landscape scale, direct counts of milkweeds, and extensive citizen science data across the breeding range suggest that a herbicide-induced, landscape-level reduction in milkweed has precipitated the decline in monarchs. A recovery will likely require a monumental effort for the re-establishment of milkweed resources at a commensurate landscape scale.
