Treatment of Tat neurotoxicity through the use of Gsk3-b inhibitors

描述（由申请人提供）：我们研究的长期目标是确定和/或开发用于治疗HAND的新疗法。在这里，我们提出研究可以抑制GSK-3¿的新型小化学分子，已知GSK-3¿在HAND中具有重要意义。这些研究可能有助于确定在HIV-1感染中起关键作用的机制，并提供一套新的预防和/或治疗靶点。在我们的初步研究中，我们已经从筛选的4000种化合物中确定了GSK-3抑制剂BIO作为tat依赖性HIV-1转录抑制剂。我们在独立的实验系统TZM-bl细胞中验证了其抑制HIV-1转录的能力，IC50为40 nM，在原代巨噬细胞中为4 nM，在感染HIV-1的U87MG细胞中为0.5 nM。MTT毒性试验表明，对原代细胞或细胞系的抑制活性均大于10 μ m。在体外GSK-3激酶抑制实验中，我们发现该药物的IC50很低，为0.03 nM。最后，我们证明了第一代BIO药物对Tat诱导的大鼠混合海马细胞死亡具有神经保护作用。因此，BIO及其衍生物是独特的化合物，因为它们具有抑制HIV-1转录和防止Tat诱导的细胞死亡的双重作用机制。基于这些初步结果，我们相信BIO或其第二代衍生物可用于治疗HAND。我们研究的短期目标是确定BIO是否是一种潜在的HAND治疗方法。我们假设BIO治疗具有神经保护作用。以下具体的目的解决我们的假设：目的1：生物抑制HIV转录的机制。目的2:BIO对HIV诱导的神经毒性的影响。

DESCRIPTION (provided by applicant): The long-term goal of our research is to identify and/or develop novel therapeutics for the treatment of HAND. Here we proposed to study novel small chemical molecules that can inhibit GSK-3¿, which is known to have important implications in HAND. These studies may help to identify mechanisms that play key roles in HIV-1 infection and provide a new set of preventive and/or therapeutic targets. In our preliminary studies, we have identified the GSK-3 inhibitor BIO, as a Tat-dependent HIV-1 transcriptional inhibitor out of 4,000 compounds screened. We have verified its ability to inhibit HIV-1 transcription in an independent assay system, TZM-bl cells, with an IC50 of 40 nM and a new BIO derivative (BIOder) at 4 nM in primary Macrophages and 0.5 nM in U87MG cells when infected with HIV-1. MTT toxicity assay shows an inhibitory activity of more than 10 uM in either primary cells or cell line. In an in vitro GSK-3¿ kinase inhibition assay, we found that the drug has a very low IC50 of 0.03 nM. Finally we demonstrated that first generation BIO drug has neuroprotective effects on Tat induced cell death in rat mixed hippocampal cultures. Therefore BIO and its derivatives are unique compounds due to their dual mechanism of action with the ability to inhibit HIV-1 transcription as well as protect against Tat induced cell death. Based on these preliminary results we believe that BIO or its 2nd generation derivatives could be used as a therapeutic for HAND. The short term goal of our research is to determine if BIO is a potential HAND therapeutic. We hypothesize that BIO treatment is neuroprotective. The following specific aims address our hypothesis: Aim 1: Mechanism of BIO inhibition of HIV transcription. Aim 2: Effect of BIO on HIV induced neurotoxicity. PUBLIC HEALTH RELEVANCE: HIV infection can result in a number of neurological disorders including HIV-associated dementia, mild neurocognitive disorder, and asymptomatic neurocognitive impairment that are not prevented with HAART. Here we proposed to study novel small chemical molecules that can inhibit GSK-3b, which is known to have important implications in HAND, with the goal of abrogating Tat induced neuropathogenesis.