The antithrombotic and antiplatelet effects of two fucoidan fractions with low molecular weight and different sulfate content from Laminaria japonica were compared in order to examine the influence of chemical charact...The antithrombotic and antiplatelet effects of two fucoidan fractions with low molecular weight and different sulfate content from Laminaria japonica were compared in order to examine the influence of chemical character on their antithrombotic activity and the possible mechanism. Both LMW fucoidan fractions exhibited favorable antithrombotic activity in an Fecl3-induced arterial thrombosis. The antithrombotic activity of LMW fucoidan was related with decrease of TXB2 and whole blood viscosity and hematocrit. LMW fucoidan showed a correlation between anticoagulant, antiaggregant and antithrombotic effects in vivo. For LMW fucoidan, antithrombotic activity required high dose of 5-10 nmol kg-1, concomitantly with increase in anticoagulant activity and inhibition of platelet aggregation. Administration of LMW fucoidan significantly promoted the 6-keto-PGF1α content and decreased the TXB2 content, indicating its inhibition of tissue factor pathway and regulation of metabolism of arachidonic acid. By comparison, highly sulfated fucoidan LF2 with Mw 3900 seemed to be a more suitable choice for antithrombotic drug for its antithrombotic activity accompanied with specific inhibitory activity on platelet aggregation, low anticoagulant activity and low hemorrhagic risk in vivo.展开更多
Plants synthesize and accumulate large amount of specialized （or secondary） metabolites also known as natural products, which provide a rich source for modem pharmacy. In China, plants have been used in traditional ...Plants synthesize and accumulate large amount of specialized （or secondary） metabolites also known as natural products, which provide a rich source for modem pharmacy. In China, plants have been used in traditional medicine for thousands of years. Recent development of molecular biology, genomics and functional genomics as well as high-throughput analytical chemical technologies has greatly promoted the research on medicinal plants. In this article, we review recent advances in the elucidation of biosynthesis of specialized metabolites in medicinal plants, including phenylpropanoids, terpenoids and alkaloids. Th- ese natural products may share a common upstream path- way to form a limited numbers of common precursors, but are characteristic in distinct modifications leading to highly variable structures. Although this review is focused on traditional Chinese medicine, other plants with a great medicinal interest or potential are also discussed. Under- standing of their biosynthesis processes is critical for producing these highly value molecules at large scale and low cost in microbes and will benefit to not only human health but also plant resource conservation.展开更多
Biodegradable polymeric nanoparticles are more and more frequently used in drug delivery systems, which represent one of the most rapidly developing areas. In our previous study, a novel natural hybrid polyester, poly...Biodegradable polymeric nanoparticles are more and more frequently used in drug delivery systems, which represent one of the most rapidly developing areas. In our previous study, a novel natural hybrid polyester, polyethylene glycol 200 （PEG200） end-capped poly （3-hydroxybutyrate-co-3-hydroxyhcxanoate） （PHBHHx-PEG） was directly produced by Aeromonas hydrophila fermentation. In this study, the performance of the novel biodegradable PHBHHx-PEG copolyester as a sustained release carrier for hydrophobic drugs with different molecular weights and the in vitro sustained release profile were investigated. 5-Fluorouracil （5-Fu, Mw=130.1）, TGX221 （Mw=364.4）, and Rapamycin （RAP, Mw=914.2） were used as the model drugs. PHBHHx-PEG nanoparticles entrapped with 5-Fu, TGX221 and RAP were fabricated by a modified emulsification/solvent evaporation method, respectively. The average diameter of 5-Fu, TGX221, and RAP loaded PHBHHx-PEG nanoparticles was between 198.2-217.4 nm, and the entrapment efficiency of the three drugs was 62.5%, 93.4% and 91.9%, respectively. The in vitro release profiles of 5-Fu, TGX221 and RAP from PHBHHx-PEG nanoparticles were different. 5-Fu showed faster release rate and an obvious initial burst release phase. TGX221 and RAP were demonstrated to be released more slowly and steadily. The release percentages of 5-Fu, TGX221 and RAP were 97.7%, 85.1% and 74.7% after releasing for 72 h. PHBHHx-PEG is a kind of promising material as a carrier for the entrapment and delivery of hydrophobic drugs especially for those drugs with high molecular weight.展开更多
基金supported in part by the Notional Natural Science Foundation of China (No.30800858)the Shandong Natural Science Foundation (No.ZR2010 CQ020)
文摘The antithrombotic and antiplatelet effects of two fucoidan fractions with low molecular weight and different sulfate content from Laminaria japonica were compared in order to examine the influence of chemical character on their antithrombotic activity and the possible mechanism. Both LMW fucoidan fractions exhibited favorable antithrombotic activity in an Fecl3-induced arterial thrombosis. The antithrombotic activity of LMW fucoidan was related with decrease of TXB2 and whole blood viscosity and hematocrit. LMW fucoidan showed a correlation between anticoagulant, antiaggregant and antithrombotic effects in vivo. For LMW fucoidan, antithrombotic activity required high dose of 5-10 nmol kg-1, concomitantly with increase in anticoagulant activity and inhibition of platelet aggregation. Administration of LMW fucoidan significantly promoted the 6-keto-PGF1α content and decreased the TXB2 content, indicating its inhibition of tissue factor pathway and regulation of metabolism of arachidonic acid. By comparison, highly sulfated fucoidan LF2 with Mw 3900 seemed to be a more suitable choice for antithrombotic drug for its antithrombotic activity accompanied with specific inhibitory activity on platelet aggregation, low anticoagulant activity and low hemorrhagic risk in vivo.
基金supported by the National Natural Science Foundation of China(31200222)Special Fund for Shanghai Landscaping Administration Bureau Program(F132424F112418 and G152421)
文摘Plants synthesize and accumulate large amount of specialized （or secondary） metabolites also known as natural products, which provide a rich source for modem pharmacy. In China, plants have been used in traditional medicine for thousands of years. Recent development of molecular biology, genomics and functional genomics as well as high-throughput analytical chemical technologies has greatly promoted the research on medicinal plants. In this article, we review recent advances in the elucidation of biosynthesis of specialized metabolites in medicinal plants, including phenylpropanoids, terpenoids and alkaloids. Th- ese natural products may share a common upstream path- way to form a limited numbers of common precursors, but are characteristic in distinct modifications leading to highly variable structures. Although this review is focused on traditional Chinese medicine, other plants with a great medicinal interest or potential are also discussed. Under- standing of their biosynthesis processes is critical for producing these highly value molecules at large scale and low cost in microbes and will benefit to not only human health but also plant resource conservation.
基金National Natural Science Foundation of Chinagrant number:81172170,81371288+1 种基金Science and Technology Research and Development Program of Shanxi Provincegrant number:2013KW32-04
文摘Biodegradable polymeric nanoparticles are more and more frequently used in drug delivery systems, which represent one of the most rapidly developing areas. In our previous study, a novel natural hybrid polyester, polyethylene glycol 200 （PEG200） end-capped poly （3-hydroxybutyrate-co-3-hydroxyhcxanoate） （PHBHHx-PEG） was directly produced by Aeromonas hydrophila fermentation. In this study, the performance of the novel biodegradable PHBHHx-PEG copolyester as a sustained release carrier for hydrophobic drugs with different molecular weights and the in vitro sustained release profile were investigated. 5-Fluorouracil （5-Fu, Mw=130.1）, TGX221 （Mw=364.4）, and Rapamycin （RAP, Mw=914.2） were used as the model drugs. PHBHHx-PEG nanoparticles entrapped with 5-Fu, TGX221 and RAP were fabricated by a modified emulsification/solvent evaporation method, respectively. The average diameter of 5-Fu, TGX221, and RAP loaded PHBHHx-PEG nanoparticles was between 198.2-217.4 nm, and the entrapment efficiency of the three drugs was 62.5%, 93.4% and 91.9%, respectively. The in vitro release profiles of 5-Fu, TGX221 and RAP from PHBHHx-PEG nanoparticles were different. 5-Fu showed faster release rate and an obvious initial burst release phase. TGX221 and RAP were demonstrated to be released more slowly and steadily. The release percentages of 5-Fu, TGX221 and RAP were 97.7%, 85.1% and 74.7% after releasing for 72 h. PHBHHx-PEG is a kind of promising material as a carrier for the entrapment and delivery of hydrophobic drugs especially for those drugs with high molecular weight.
