OBJECTIVE To determine the characterization,anti-tumor efficacy and pharmacokinetics of bufalin-loaded PEGylated liposomes compared with bufalin entity.METHODS Bufalin-loaded PEGylated liposomes and bufalin-loaded lip...OBJECTIVE To determine the characterization,anti-tumor efficacy and pharmacokinetics of bufalin-loaded PEGylated liposomes compared with bufalin entity.METHODS Bufalin-loaded PEGylated liposomes and bufalin-loaded liposomes were prepared reproducibly with homogeneous particle size by the combination of thin film evaporation method and high pressure homogenization method.The particle size and zeta potential of the liposomes were determined by dynamic light scattering technique.The direct imaging of morphology of liposomes was charactered by transmission electron microscope.The content of bufalin in liposomes was analysed by HPLC method.The entrapment efficiency and the particle size was applied to assess the stability profile,after storage at 4℃ on day 0,7,15,30 and 90.The in-vitro release behaviours of bufalin from liposomes were conducted using dialysis bag technique at 37℃.In-vitro cytotoxicity studies were carried out using MTT[3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide]assay on several kinds of tumor cel lines including SW620,PC-3,MDA-MB-231,A549,U251,U87 and HepG2.In-vivo pharmacokinetic study of bufalin liposomes was evaluated by HPLC method.RESULTS Their mean particle sizes were 127.6 nm and 155.0 nm,mean zeta potentials were 2.24 m V and-18.5 m V,entrapment efficiencies were 76.31%and 78.40%,respectively.In-vitro release profile revealed that the release of bufalin in bufalin-loaded PEGylated liposomes was slower than that of bufalin-loaded liposomes.The cytotoxicity of blank liposomes has been found within acceptable range,whereas bufalin-loaded PEGylated liposomes showed enhanced cytotoxicity to U251 cells compared with bufalin entity.In-vivo pharmacokinetics indicated that bufalinloaded PEGylated liposomes could extend eliminate half-life time of bufalin in plasma in rats.CONCLUSION The results suggested that bufalin-loaded PEGylated liposomes improved the solubility and increased the drug concentration in plasma.展开更多
OBJECTIVE Toad venom(Venenum Bufonis)isalways used for analgesia in China from ancient to modern times,but the effective component of it remains unclear.METHODS In the present study,we investigated the anti-nociceptiv...OBJECTIVE Toad venom(Venenum Bufonis)isalways used for analgesia in China from ancient to modern times,but the effective component of it remains unclear.METHODS In the present study,we investigated the anti-nociceptive effect and the underlying mechanism ofbufalin,an active ingredient fromtoad venom by animal behavior,patch clamp and calcium imaging.RESULTS Bufalin could significantly relieve formalin-induced spontaneous flinching and licking response as well as carrageenan-induced mechanical and thermal hyperalgesia.Using the whole-cel patch-clamp recording,bufalincaused remarkable suppressive effect on the peak currents of Na+channels in dorsal root ganglion neuroblastoma ND7-23 cel line in a U-shaped dependent manner.In addition,bufalinprompted the voltage-dependent activationand caused a negative shift of the fast-state inactivation of Na+channels.However,bufalin produced insignificant effect not onlyon voltage-dependent Kv4.2,Kv4.3 and BK channels,but also on the capsaicin induced Ca2+influx.CONCLUSION The present results indicate bufalin is capable of producing remarkable anti-nociceptive effects whichis probably ascribed to its specific modulation of voltage-gated Na+channels.展开更多
基金Supported by Overall Innovation Plan Projects of Science and Technology of Shaanxi Province in China(2015KTZDSF02-01-02)
文摘OBJECTIVE To determine the characterization,anti-tumor efficacy and pharmacokinetics of bufalin-loaded PEGylated liposomes compared with bufalin entity.METHODS Bufalin-loaded PEGylated liposomes and bufalin-loaded liposomes were prepared reproducibly with homogeneous particle size by the combination of thin film evaporation method and high pressure homogenization method.The particle size and zeta potential of the liposomes were determined by dynamic light scattering technique.The direct imaging of morphology of liposomes was charactered by transmission electron microscope.The content of bufalin in liposomes was analysed by HPLC method.The entrapment efficiency and the particle size was applied to assess the stability profile,after storage at 4℃ on day 0,7,15,30 and 90.The in-vitro release behaviours of bufalin from liposomes were conducted using dialysis bag technique at 37℃.In-vitro cytotoxicity studies were carried out using MTT[3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide]assay on several kinds of tumor cel lines including SW620,PC-3,MDA-MB-231,A549,U251,U87 and HepG2.In-vivo pharmacokinetic study of bufalin liposomes was evaluated by HPLC method.RESULTS Their mean particle sizes were 127.6 nm and 155.0 nm,mean zeta potentials were 2.24 m V and-18.5 m V,entrapment efficiencies were 76.31%and 78.40%,respectively.In-vitro release profile revealed that the release of bufalin in bufalin-loaded PEGylated liposomes was slower than that of bufalin-loaded liposomes.The cytotoxicity of blank liposomes has been found within acceptable range,whereas bufalin-loaded PEGylated liposomes showed enhanced cytotoxicity to U251 cells compared with bufalin entity.In-vivo pharmacokinetics indicated that bufalinloaded PEGylated liposomes could extend eliminate half-life time of bufalin in plasma in rats.CONCLUSION The results suggested that bufalin-loaded PEGylated liposomes improved the solubility and increased the drug concentration in plasma.
基金The project supported by Innovation Program of Shanghai Municipal Education Commission(15ZZ063)by Research Project of Putuo Hospital,Shanghai University of Traditional Chinese Medicine(2014YJ002)
文摘OBJECTIVE Toad venom(Venenum Bufonis)isalways used for analgesia in China from ancient to modern times,but the effective component of it remains unclear.METHODS In the present study,we investigated the anti-nociceptive effect and the underlying mechanism ofbufalin,an active ingredient fromtoad venom by animal behavior,patch clamp and calcium imaging.RESULTS Bufalin could significantly relieve formalin-induced spontaneous flinching and licking response as well as carrageenan-induced mechanical and thermal hyperalgesia.Using the whole-cel patch-clamp recording,bufalincaused remarkable suppressive effect on the peak currents of Na+channels in dorsal root ganglion neuroblastoma ND7-23 cel line in a U-shaped dependent manner.In addition,bufalinprompted the voltage-dependent activationand caused a negative shift of the fast-state inactivation of Na+channels.However,bufalin produced insignificant effect not onlyon voltage-dependent Kv4.2,Kv4.3 and BK channels,but also on the capsaicin induced Ca2+influx.CONCLUSION The present results indicate bufalin is capable of producing remarkable anti-nociceptive effects whichis probably ascribed to its specific modulation of voltage-gated Na+channels.