Human Immunodeficiency Virus Type 1 exists in vivo as quasispecies, and one of the genome's characteristics is its diversity. During the antiretroviral therapy, drug resistance is the main obstacle to effective vi...Human Immunodeficiency Virus Type 1 exists in vivo as quasispecies, and one of the genome's characteristics is its diversity. During the antiretroviral therapy, drug resistance is the main obstacle to effective viral prevention. Understanding the molecular evolution process is fundamental to analyze the mechanism of drug resistance and develop a strategy to minimize resistance. Objective: The molecular evolution of drug resistance of one patient who had received reverse transcriptase inhibitors for a long time and had treatment which replaced Nevirapine with Indinavir was analyzed, with the aim of observing the drug resistance evolution pathway. Methods: The patient, XLF, was followed-up for six successive times. The viral populations were amplified and sequenced by single-genome amplification. All the sequences were submitted to the Stanford HIV Drug Resistance Database for the analysis of genotypic drug resistance. Results: 149 entire protease and 171 entire reverse transcriptase sequences were obtained from these samples, and all sequences were identified as subtype B. Before the patient received Indinavir, the viral population only had some polymorphisms in the protease sequences. After the patient began Indinavir treatment, the variants carrying polymorphisms declined while variants carrying the secondary mutation G73S gained the advantage. As therapy was prolonged, G73S was combined with M46I/L90M to form a resistance pattern M46I/G73S/L90M, which then became the dominant population. 97.9% of variants had the M46I/G73S/L90M pattern at XLF6. During the emergence of protease inhibitors resistance, reverse transcriptase inhibitors resistance maintained high levels. Conclusion: Indinavirresistance evolution was observed by single-genome amplification. During the course of changing the regimen to incorporate Indinavir, the G73S mutation occurred and was combined with M46I/L90M.展开更多
Indinavir is a protease inhibitor used in the treatment of HIV infection.However,it has limited efficacy in eradicating the virus in the brain due to efflux by P-glycoprotein(P-gp)expressed at the blood–brain barrier...Indinavir is a protease inhibitor used in the treatment of HIV infection.However,it has limited efficacy in eradicating the virus in the brain due to efflux by P-glycoprotein(P-gp)expressed at the blood–brain barrier(BBB).The objective of this work was to develop an o/w lipid nanoemulsion(LNE)of indinavir using Tween 80 as co-emulsifier to improve its brain specific delivery.LNEs were prepared with different compositions and were characterized for globule size,polydispersity index,zeta potential and in vitro drug release.Five formulations were then evaluated for drug content,entrapment efficiency and stability after which brain uptake studies were carried out using fluorescent labeled LNEs and pharmacokinetic(PK)and tissue distribution studies were conducted after intravenous administration in mice.Brain uptake of indinavir was shown to be improved for a 1%Tween 80 containing formulation(F5)compared to a formulation containing 0.3%cholesterol(F2).In PK studies,the brain level of indinavir subsequent to administration of F5 was significantly(Po0.05)higher than produced by administration of a drug solution(2.44-fold)or a control nanoemulsion(F1)(1.48-fold)or formulation F2(1.6-fold).The increased brain specific accumulation of indinavir from F5 is probably due to enhanced low density lipoprotein-mediated endocytosis and P-gp inhibition by Tween 80 at the BBB.These results suggest Tween 80 containing LNEs could provide a simple but effective means of delivering indinavir to brain.展开更多
基金National Natural Science Foundation of China (30830088 and 30800938)The National Key and Special Projects on Major Infectious Disease Grant (2008 ZX10001-004)
文摘Human Immunodeficiency Virus Type 1 exists in vivo as quasispecies, and one of the genome's characteristics is its diversity. During the antiretroviral therapy, drug resistance is the main obstacle to effective viral prevention. Understanding the molecular evolution process is fundamental to analyze the mechanism of drug resistance and develop a strategy to minimize resistance. Objective: The molecular evolution of drug resistance of one patient who had received reverse transcriptase inhibitors for a long time and had treatment which replaced Nevirapine with Indinavir was analyzed, with the aim of observing the drug resistance evolution pathway. Methods: The patient, XLF, was followed-up for six successive times. The viral populations were amplified and sequenced by single-genome amplification. All the sequences were submitted to the Stanford HIV Drug Resistance Database for the analysis of genotypic drug resistance. Results: 149 entire protease and 171 entire reverse transcriptase sequences were obtained from these samples, and all sequences were identified as subtype B. Before the patient received Indinavir, the viral population only had some polymorphisms in the protease sequences. After the patient began Indinavir treatment, the variants carrying polymorphisms declined while variants carrying the secondary mutation G73S gained the advantage. As therapy was prolonged, G73S was combined with M46I/L90M to form a resistance pattern M46I/G73S/L90M, which then became the dominant population. 97.9% of variants had the M46I/G73S/L90M pattern at XLF6. During the emergence of protease inhibitors resistance, reverse transcriptase inhibitors resistance maintained high levels. Conclusion: Indinavirresistance evolution was observed by single-genome amplification. During the course of changing the regimen to incorporate Indinavir, the G73S mutation occurred and was combined with M46I/L90M.
基金support of RPS project(F.No.8023/BOR/RID/RPS-155/2008-2009)。
文摘Indinavir is a protease inhibitor used in the treatment of HIV infection.However,it has limited efficacy in eradicating the virus in the brain due to efflux by P-glycoprotein(P-gp)expressed at the blood–brain barrier(BBB).The objective of this work was to develop an o/w lipid nanoemulsion(LNE)of indinavir using Tween 80 as co-emulsifier to improve its brain specific delivery.LNEs were prepared with different compositions and were characterized for globule size,polydispersity index,zeta potential and in vitro drug release.Five formulations were then evaluated for drug content,entrapment efficiency and stability after which brain uptake studies were carried out using fluorescent labeled LNEs and pharmacokinetic(PK)and tissue distribution studies were conducted after intravenous administration in mice.Brain uptake of indinavir was shown to be improved for a 1%Tween 80 containing formulation(F5)compared to a formulation containing 0.3%cholesterol(F2).In PK studies,the brain level of indinavir subsequent to administration of F5 was significantly(Po0.05)higher than produced by administration of a drug solution(2.44-fold)or a control nanoemulsion(F1)(1.48-fold)or formulation F2(1.6-fold).The increased brain specific accumulation of indinavir from F5 is probably due to enhanced low density lipoprotein-mediated endocytosis and P-gp inhibition by Tween 80 at the BBB.These results suggest Tween 80 containing LNEs could provide a simple but effective means of delivering indinavir to brain.
