Department of Pharmacotherapy and Outcomes Science, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia, USA.
Institut Cochin, Paris, France.
Antimicrob Agents Chemother. 2017 Nov 22;61(12). doi: 10.1128/AAC.01307-17. Print 2017 Dec.
Human immunodeficiency (HIV) infection results in neurocognitive deficits in about one half of infected individuals. Despite systemic effectiveness, restricted antiretroviral penetration across the blood-brain barrier (BBB) is a major limitation in fighting central nervous system (CNS)-localized infection. Drug abuse exacerbates HIV-induced cognitive and pathological CNS changes. This study's purpose was to investigate the effects of the HIV-1 protein Tat and methamphetamine on factors affecting drug penetration across an BBB model. Factors affecting paracellular and transcellular flux in the presence of Tat and methamphetamine were examined. Transendothelial electrical resistance, ZO-1 expression, and lucifer yellow (a paracellular tracer) flux were aspects of paracellular processes that were examined. Additionally, effects on P-glycoprotein (P-gp) and multidrug resistance protein 1 (MRP-1) mRNA (via quantitative PCR [qPCR]) and protein (via immunoblotting) expression were measured; Pgp and MRP-1 are drug efflux proteins. Transporter function was examined after exposure of Tat with or without methamphetamine using the P-gp substrate rhodamine 123 and also using the dual P-gp/MRP-1 substrate and protease inhibitor atazanavir. Tat and methamphetamine elicit complex changes affecting transcellular and paracellular transport processes. Neither Tat nor methamphetamine significantly altered P-gp expression. However, Tat plus methamphetamine exposure significantly increased rhodamine 123 accumulation within brain endothelial cells, suggesting that treatment inhibited or impaired P-gp function. Intracellular accumulation of atazanavir was not significantly altered after Tat or methamphetamine exposure. Atazanavir accumulation was, however, significantly increased by simultaneous inhibition of P-gp and MRP. Collectively, our investigations indicate that Tat and methamphetamine alter aspects of BBB integrity without affecting net flux of paracellular compounds. Tat and methamphetamine may also affect several aspects of transcellular transport.
人类免疫缺陷病毒（HIV）感染会导致大约一半感染者出现神经认知缺陷。尽管抗逆转录病毒药物具有系统疗效，但由于血脑屏障（BBB）对药物的穿透性有限，因此这是治疗中枢神经系统（CNS）局部感染的主要限制因素。药物滥用会加剧 HIV 引起的认知和病理 CNS 变化。本研究的目的是研究 HIV-1 蛋白 Tat 和冰毒对影响 BBB 模型中药物穿透的因素的影响。研究了 Tat 和冰毒存在时影响细胞旁和细胞内通量的因素。还检查了跨内皮电阻、ZO-1 表达和荧光素黄（细胞旁示踪剂）通量等细胞旁过程的方面。此外，还通过定量 PCR（qPCR）和免疫印迹测量了对 P-糖蛋白（P-gp）和多药耐药蛋白 1（MRP-1）mRNA（通过 qPCR）和蛋白（通过免疫印迹）表达的影响；P-gp 和 MRP-1 是药物外排蛋白。在用 Tat 加或不加冰毒处理后，使用 P-gp 底物罗丹明 123 以及双重 P-gp/MRP-1 底物和蛋白酶抑制剂阿扎那韦检查了转运蛋白的功能。 Tat 和冰毒会引起影响细胞内和细胞旁转运过程的复杂变化。Tat 或冰毒均未显著改变 P-gp 表达。然而，Tat 加冰毒暴露会显著增加脑内皮细胞内罗丹明 123 的积累，这表明治疗抑制或损害了 P-gp 功能。 Tat 或冰毒暴露后，阿扎那韦的细胞内积累没有明显改变。然而，同时抑制 P-gp 和 MRP 会显著增加阿扎那韦的积累。总的来说，我们的研究表明，Tat 和冰毒会改变 BBB 完整性的各个方面，而不会影响细胞旁化合物的净通量。 Tat 和冰毒还可能影响几个细胞内转运的方面。
