Ubiquitin-proteasome system(UPS)plays an important role in neurodegenerative diseases,such as Alzheimer’s disease(AD),Parkinson’s disease(PD),and Huntington’s disease(HD).The discovery of UPS activators for anti-ne...Ubiquitin-proteasome system(UPS)plays an important role in neurodegenerative diseases,such as Alzheimer’s disease(AD),Parkinson’s disease(PD),and Huntington’s disease(HD).The discovery of UPS activators for anti-neurodegenerative diseases is becoming increasingly important.In this study,we aimed to identify potential UPS activators using the high-throughput screening method with the high-content fluorescence imaging system and validate the neuroprotective effect in the cell models of AD.At first,stable YFP-CL1 HT22 cells were successfully constructed by transfecting the YFP-CL1 plasmid into HT22 cells,together with G418 screening.The degradation activity of the test compounds via UPS was monitored by detecting the YFP fluorescence intensity reflected by the ubiquitin-proteasome degradation signal CL1.By employing the high-content fluorescence imaging system,together with stable YFP-CL1 HT22 cells,the UPS activators were successfully screened from our established TCM library.The representative images were captured and analyzed,and quantification of the YFP fluorescence intensity was performed by flow cytometry.Then,the neuroprotective effect of the UPS activators was investigated in pEGFP-N1-APP(APP),pRK5-EGFP-Tau P301L(Tau P301L),or pRK5-EGFP-Tau(Tau)transiently transfected HT22 cells using fluorescence imaging,flow cytometry,and Western blot.In conclusion,our study established a high-content fluorescence imaging system coupled with stable YFP-CL1 HT22 cells for the highthroughput screening of the UPS activators.Three compounds,namely salvianolic acid A(SAA),salvianolic acid B(SAB),and ellagic acid(EA),were identified to significantly decrease YFP fluorescence intensity,which suggested that these three compounds are UPS activators.The identified UPS activators were demonstrated to clear AD-related proteins,including APP,Tau,and Tau P301L.Therefore,these findings provide a novel insight into the discovery and development of anti-AD drugs.展开更多
To study the biopharmaceutics characteristics of paris saponin Ⅶ(PSⅦ). The solubility of PSⅦ was evaluated by measurement of the equilibrium solubility in different solvents and media. The permeability of PSⅦ was ...To study the biopharmaceutics characteristics of paris saponin Ⅶ(PSⅦ). The solubility of PSⅦ was evaluated by measurement of the equilibrium solubility in different solvents and media. The permeability of PSⅦ was evaluated by measuring the oil/water partition coefficient(lgP_(app)) and determining the apparent permeability coefficient(PC_(app)) on a mono-layer Caco-2 cell model. The effects of p-glycoprotein and multidrug resistance related protein 2 on PSⅦ transport in mono-layer Caco-2 cell model were further investigated. Finally, the small intestinal absorption of PSⅦ was investigated in rat. In solvents of different pH, the equilibrium solubility of PSⅦ was quite low, and the dose number of PSⅦ was larger than 1. The lgP_(app) of PSⅦ was less than 0. The apparent permeability coefficient [PC_(app)(AP-BL)] of PSⅦ in mono-layer Caco-2 cell model was less than 14.96 × 10^(-6) cm·s^(-1), and the efflux ratio of PSⅦ in mono-layer Caco-2 cell model was less than 1. The transport rate of PSⅦ in mono-layer Caco-2 cell model was not affected by the inhibitors of p-glycoprotein and multidrug resistance related protein 2. After oral administration, PSⅦ could be detected in rat intestinal contents, but could not be detected in the small intestinal mucosa. PSⅦ showed low solubility and permeability,which would result in low oral bioavailability in clinic. PSⅦ belonged to Class IV compound in biopharmaceutics classification system.展开更多
基金the Joint Project of Luzhou Municipal People’s Government and Southwest Medical University(No.2020LZXNYDJ37)the National Natural Science Foundation of China(Nos.81903829 and 81801398)+2 种基金the Science and Technology Planning Project of Sichuan Province(Nos.2019JDPT0010 and 2020YJ0494)the Project of Southwest Medical University(Nos.2021ZKZD015,2021ZKZD018,and 2021-ZKMS046)Sichuan University Student Innovation and Entrepreneurship Project(Nos.2019424 and 201816032066).
文摘Ubiquitin-proteasome system(UPS)plays an important role in neurodegenerative diseases,such as Alzheimer’s disease(AD),Parkinson’s disease(PD),and Huntington’s disease(HD).The discovery of UPS activators for anti-neurodegenerative diseases is becoming increasingly important.In this study,we aimed to identify potential UPS activators using the high-throughput screening method with the high-content fluorescence imaging system and validate the neuroprotective effect in the cell models of AD.At first,stable YFP-CL1 HT22 cells were successfully constructed by transfecting the YFP-CL1 plasmid into HT22 cells,together with G418 screening.The degradation activity of the test compounds via UPS was monitored by detecting the YFP fluorescence intensity reflected by the ubiquitin-proteasome degradation signal CL1.By employing the high-content fluorescence imaging system,together with stable YFP-CL1 HT22 cells,the UPS activators were successfully screened from our established TCM library.The representative images were captured and analyzed,and quantification of the YFP fluorescence intensity was performed by flow cytometry.Then,the neuroprotective effect of the UPS activators was investigated in pEGFP-N1-APP(APP),pRK5-EGFP-Tau P301L(Tau P301L),or pRK5-EGFP-Tau(Tau)transiently transfected HT22 cells using fluorescence imaging,flow cytometry,and Western blot.In conclusion,our study established a high-content fluorescence imaging system coupled with stable YFP-CL1 HT22 cells for the highthroughput screening of the UPS activators.Three compounds,namely salvianolic acid A(SAA),salvianolic acid B(SAB),and ellagic acid(EA),were identified to significantly decrease YFP fluorescence intensity,which suggested that these three compounds are UPS activators.The identified UPS activators were demonstrated to clear AD-related proteins,including APP,Tau,and Tau P301L.Therefore,these findings provide a novel insight into the discovery and development of anti-AD drugs.
文摘To study the biopharmaceutics characteristics of paris saponin Ⅶ(PSⅦ). The solubility of PSⅦ was evaluated by measurement of the equilibrium solubility in different solvents and media. The permeability of PSⅦ was evaluated by measuring the oil/water partition coefficient(lgP_(app)) and determining the apparent permeability coefficient(PC_(app)) on a mono-layer Caco-2 cell model. The effects of p-glycoprotein and multidrug resistance related protein 2 on PSⅦ transport in mono-layer Caco-2 cell model were further investigated. Finally, the small intestinal absorption of PSⅦ was investigated in rat. In solvents of different pH, the equilibrium solubility of PSⅦ was quite low, and the dose number of PSⅦ was larger than 1. The lgP_(app) of PSⅦ was less than 0. The apparent permeability coefficient [PC_(app)(AP-BL)] of PSⅦ in mono-layer Caco-2 cell model was less than 14.96 × 10^(-6) cm·s^(-1), and the efflux ratio of PSⅦ in mono-layer Caco-2 cell model was less than 1. The transport rate of PSⅦ in mono-layer Caco-2 cell model was not affected by the inhibitors of p-glycoprotein and multidrug resistance related protein 2. After oral administration, PSⅦ could be detected in rat intestinal contents, but could not be detected in the small intestinal mucosa. PSⅦ showed low solubility and permeability,which would result in low oral bioavailability in clinic. PSⅦ belonged to Class IV compound in biopharmaceutics classification system.
