A bivalent ligand targeting the putative mu opioid receptor and chemokine receptor CCR5 heterodimer: binding affinity versus functional activities
作者:Yunyun Yuan、Christopher K. Arnatt、Nazira El-Hage、Seth M. Dever、Joanna C. Jacob、Dana E. Selley、Kurt F. Hauser、Yan Zhang
DOI:10.1039/c3md00080j
日期:——
Opioid substitution and antiretroviral therapies have steadily increased the life spans of AIDS patients with opioid addiction, while the adverse drug–drug interactions and persistence of HIV-associated neurocognitive disorders still require new strategies to target opioid abuse and HIV-1 comorbidities. A bivalent ligand 1 with a 21-atom spacer was thus synthesized and explicitly characterized as a novel pharmacological probe to study the underlying mechanism of opioid-enhanced NeuroAIDS. The steric hindrance generated from the spacer affected the binding affinity and Ca2+ flux inhibition functional activity of bivalent ligand 1 at the chemokine receptor CCR5 more profoundly than it did at the mu opioid receptor (MOR). However, the CCR5 radioligand binding affinity and the Ca2+ flux inhibition function of the ligand seemed not necessarily to correlate with its antiviral activity given that it was at least two times more potent than maraviroc alone in reducing Tat expression upon HIV-1 infection in human astrocytes. Furthermore, the ligand was also about two times more potent than the simple mixture of maraviroc and naltrexone in the same viral entry inhibition assay. Therefore bivalent ligand 1 seemed to function more effectively by targeting specifically the putative MOR–CCR5 heterodimer in the viral invasion process. The results reported here suggest that a properly designed bivalent ligand may serve as a useful chemical probe to study the potential MOR–CCR5 interaction during the progression of NeuroAIDS.
阿片类药物替代疗法和抗逆转录病毒疗法稳步延长了阿片类药物成瘾艾滋病患者的寿命,而药物间的不良相互作用和艾滋病毒相关神经认知障碍的持续存在仍然需要针对阿片类药物滥用和艾滋病毒-1合并症的新策略。因此,我们合成了一种具有 21 原子间隔的二价配体 1,并将其明确表征为一种新型药理学探针,用于研究阿片类药物增强神经艾滋病的潜在机制。间隔产生的立体阻碍对二价配体 1 与趋化因子受体 CCR5 的结合亲和力和 Ca2+ 通量抑制功能活性的影响比对μ阿片受体(MOR)的影响更大。然而,该配体的 CCR5 放射配体结合亲和力和 Ca2+ 通量抑制功能似乎与其抗病毒活性并无必然联系,因为在人类星形胶质细胞感染 HIV-1 病毒后,该配体在减少 Tat 表达方面的效力至少是马拉韦罗单药的两倍。此外,在相同的病毒进入抑制试验中,配体的效力也比马拉韦罗和纳曲酮的简单混合物高出约两倍。因此,二价配体 1 似乎能更有效地在病毒入侵过程中专门针对假定的 MOR-CCR5 异二聚体发挥作用。本文报告的结果表明,适当设计的二价配体可作为一种有用的化学探针,用于研究神经性艾滋病进展过程中潜在的 MOR-CCR5 相互作用。