Saponins are the main triterpenoid ingredients from Panax notoginseng,a well-known Chinese medicine,and are important sources for producing drugs to prevent and treat cerebrovascular and cardiovascular diseases.Howeve...Saponins are the main triterpenoid ingredients from Panax notoginseng,a well-known Chinese medicine,and are important sources for producing drugs to prevent and treat cerebrovascular and cardiovascular diseases.However,the transcriptional regulatory network of saponin biosynthesis in P.notoginseng is largely unknown.In the present study we demonstrated that one R2R3-MYB transcription factor,designated PnMYB4,acts as a repressor of saponin accumulation.Suppression of PnMYB4 in P.notoginseng calli significantly increased the saponin content and the expression level of saponin biosynthetic genes.PnMYB4 directly bound to the promoters of key saponin biosynthetic genes,including PnSS,PnSE,and PnDS,to repress saponin accumulation.PnMYB4 and the activator PnMYB1 could inter-acted with PnbHLH,which is a positive regulator of saponin biosynthesis,to modulate the biosynthesis of saponin.PnMYB4 competed with PnMYB1 for binding to PnbHLH,repressing activation of the promoters of saponin structural genes induced by the PnMYB1-PnbHLH complex.Our study reveals that a complex regulatory module of saponin biosynthesis is associated with positive and negative MYB transcriptional regulators and provides a theoretical basis for improving the content of saponins and efficacy of P.notoginseng.展开更多
Triptolide(TP),a major active component of Tripterygium wilfordii Hook.F.(TWHF),is used to treat rheumatoid arthritis(RA).However,it has a narrow therapeutic window due to its serious toxicities.To increase the therap...Triptolide(TP),a major active component of Tripterygium wilfordii Hook.F.(TWHF),is used to treat rheumatoid arthritis(RA).However,it has a narrow therapeutic window due to its serious toxicities.To increase the therapeutic index,a new triptolide-loaded transdermal delivery system,named triptolide-loaded liposome hydrogel patch(TP-LHP),has been developed.In this paper,we used a micro-needle array to deliver TP-LHP to promote transdermal absorption and evaluated this treatment on the pharmacokinetics and pharmacodynamics of TP-LHP in a rat model of collagen-induced arthritis(CIA).The pharmacokinetic results showed that transdermal delivery of microneedle TP-LHP yielded plasma drug levels which fit a onecompartment open model.The relationship equation between plasma concentration and time was C=303.59(e 0.064 t e 0.287t).The results of pharmacodynamic study demonstrated that TP-LHP treatment mitigated the degree of joint swelling and suppressed the expressions of fetal liver kinase-1,fetal liver tyrosine kinase-4 and hypoxia-inducible factor-1α in synovium.Other indicators were also reduced by TP-LHP,including hyperfunction of immune,interleukin-1β and interleukin-6 levels in serum.The therapeutic mechanism of TP-LHP might be regulation of the balance between Th1 and Th2,as well as inhibition of the expression and biological effects of vascular endothelial growth factor.展开更多
The anatase nano-TiO2 powder, with crystal size between 40 and 80 nm, was prepared by the liquid phase hydrolysis of TiCl4. At the same time, the nano-TiO2 was utilized with the baker’s yeast biomass as a composite a...The anatase nano-TiO2 powder, with crystal size between 40 and 80 nm, was prepared by the liquid phase hydrolysis of TiCl4. At the same time, the nano-TiO2 was utilized with the baker’s yeast biomass as a composite adsorbent to adsorb the Cu ions in the artificial aqueous solution. The investigation showed that the composite adsorbent had a fine adsorption efficiency. The TiO2 in the composite ad- sorbent could cooperate well with baker’s yeast to improve the adsorbing capability of Cu2+ under the following experimental conditions as well: a quantity of composite adsorbent of 5 g·L?1, pH≥4.0, an adsorption time of 40 min and an initial concentration of Cu ions of 10 mg·L?1. In addition, the results of measurements, obtained with a scanning electron microscope, an infrared spectrophotometer and a Zeta potential analyzer, revealed that the baker’s yeast and nano-TiO2 produced the composite ad- sorbent through coordination and hydrogen bonds in particular, etc. The stability of the composite adsorbent and the amount of titania loaded were largely dependent on the concentration of hydrogen ion in the solution.展开更多
基金This study was supported by Beijing Science and Technology Planning Project(Z201100005420005,China).
文摘Saponins are the main triterpenoid ingredients from Panax notoginseng,a well-known Chinese medicine,and are important sources for producing drugs to prevent and treat cerebrovascular and cardiovascular diseases.However,the transcriptional regulatory network of saponin biosynthesis in P.notoginseng is largely unknown.In the present study we demonstrated that one R2R3-MYB transcription factor,designated PnMYB4,acts as a repressor of saponin accumulation.Suppression of PnMYB4 in P.notoginseng calli significantly increased the saponin content and the expression level of saponin biosynthetic genes.PnMYB4 directly bound to the promoters of key saponin biosynthetic genes,including PnSS,PnSE,and PnDS,to repress saponin accumulation.PnMYB4 and the activator PnMYB1 could inter-acted with PnbHLH,which is a positive regulator of saponin biosynthesis,to modulate the biosynthesis of saponin.PnMYB4 competed with PnMYB1 for binding to PnbHLH,repressing activation of the promoters of saponin structural genes induced by the PnMYB1-PnbHLH complex.Our study reveals that a complex regulatory module of saponin biosynthesis is associated with positive and negative MYB transcriptional regulators and provides a theoretical basis for improving the content of saponins and efficacy of P.notoginseng.
基金supported by National Science and Technology Major Project on Significant Creation of New Drugs of China(2009ZX09502-019)
文摘Triptolide(TP),a major active component of Tripterygium wilfordii Hook.F.(TWHF),is used to treat rheumatoid arthritis(RA).However,it has a narrow therapeutic window due to its serious toxicities.To increase the therapeutic index,a new triptolide-loaded transdermal delivery system,named triptolide-loaded liposome hydrogel patch(TP-LHP),has been developed.In this paper,we used a micro-needle array to deliver TP-LHP to promote transdermal absorption and evaluated this treatment on the pharmacokinetics and pharmacodynamics of TP-LHP in a rat model of collagen-induced arthritis(CIA).The pharmacokinetic results showed that transdermal delivery of microneedle TP-LHP yielded plasma drug levels which fit a onecompartment open model.The relationship equation between plasma concentration and time was C=303.59(e 0.064 t e 0.287t).The results of pharmacodynamic study demonstrated that TP-LHP treatment mitigated the degree of joint swelling and suppressed the expressions of fetal liver kinase-1,fetal liver tyrosine kinase-4 and hypoxia-inducible factor-1α in synovium.Other indicators were also reduced by TP-LHP,including hyperfunction of immune,interleukin-1β and interleukin-6 levels in serum.The therapeutic mechanism of TP-LHP might be regulation of the balance between Th1 and Th2,as well as inhibition of the expression and biological effects of vascular endothelial growth factor.
基金Supported by the National Natural Science Foundation of China (Grant No. 30671530)the Key Basic Research Program of the Sichan Provincial Education Commission (Grant No. 2005A014)
文摘The anatase nano-TiO2 powder, with crystal size between 40 and 80 nm, was prepared by the liquid phase hydrolysis of TiCl4. At the same time, the nano-TiO2 was utilized with the baker’s yeast biomass as a composite adsorbent to adsorb the Cu ions in the artificial aqueous solution. The investigation showed that the composite adsorbent had a fine adsorption efficiency. The TiO2 in the composite ad- sorbent could cooperate well with baker’s yeast to improve the adsorbing capability of Cu2+ under the following experimental conditions as well: a quantity of composite adsorbent of 5 g·L?1, pH≥4.0, an adsorption time of 40 min and an initial concentration of Cu ions of 10 mg·L?1. In addition, the results of measurements, obtained with a scanning electron microscope, an infrared spectrophotometer and a Zeta potential analyzer, revealed that the baker’s yeast and nano-TiO2 produced the composite ad- sorbent through coordination and hydrogen bonds in particular, etc. The stability of the composite adsorbent and the amount of titania loaded were largely dependent on the concentration of hydrogen ion in the solution.
