AntiretroviraI induced Defects in Muscle Protein Synthes

说明(由申请人提供)：本申请是针对NOT-OD-09-058号通知(NIH宣布恢复法资金可用于竞争性修订申请)而提交的，并根据ARRA 2009要求提供竞争性补充。我们的父母资助提供了关于HIV-1蛋白酶抑制剂如indinavir和lopinavir(LPV)减少骨骼肌蛋白质合成的机制见解。家长基金的长期目标是阐明LPV和其他蛋白酶抑制剂导致肌肉肌病的机制。在进行亲本申请中描述的研究时，我们报告了HIV-1转基因(TG)大鼠，它们是非传染性的，并结构性地表达9种病毒包膜蛋白中的7种，表现出肌肉萎缩，而不是由于热量摄入减少或能量消耗增加。我们现在已经给HIV-1TG大鼠服用LPV 3个月，观察到的消瘦明显大于没有LPV的HIV-1TG大鼠。此外，我们有证据表明，LPV和HIV-1病毒蛋白的共存降低了基础吸收后状态下肌肉蛋白质的合成。最后，我们还注意到服用LPV的HIV-1TG大鼠存在明显的葡萄糖耐量、胰岛素抵抗和骨骼肌甘油三酯的异位沉积。因此，很明显，在一种或多种病毒蛋白(不是HIV-1病毒本身)和产生戏剧性代谢表型的蛋白酶抑制剂之间存在着强烈的相互作用。由于药物与病毒蛋白的相互作用，检测蛋白酶抑制剂和其他HAART药物在HIV-1TG大鼠体内的作用似乎可能提供一个更具临床相关性的模型。因此，这项竞争性修订的目标是确定给HIV-1TG大鼠注射LPV产生这种复杂代谢表型的机制-主要关注肌肉中葡萄糖和蛋白质代谢的变化。虽然相关，但这类研究超出了父母赠款的直接范围。然而，我们的挑衅性数据值得进一步调查，拟议的研究可以在两年内完成。这一竞争修订要求为四个特定目的提供资金：1)聘请一名失业的博士后研究员；2)聘请一名高中化学教师作为暑期实习生；3)购买HIV-1转基因大鼠，这是非常昂贵的；以及4)为研究员和实习生购买必要的用品，以便有一个有效的培训环境，并在2年内成功完成指定的学习。由于拟议的研究不是家长申请的一部分，因此没有足够的未承付资金。在父母应用的最初几年里，我们一直非常富有成效，在这一竞争性修订中提供的资金将极大地加快我们在确定蛋白质酶抑制剂在HIV感染者中产生的肌肉萎缩和胰岛素抵抗的细胞和分子基础方面的研究。 公共卫生相关性：那些感染艾滋病毒-1的患者的肌肉萎缩和胰岛素抵抗通常独立于艾滋病而发生，可能是这些人接受艾滋病毒蛋白酶抑制剂药物治疗的直接结果。我们使用HIV-1转基因大鼠进行的研究旨在阐明这种药物对翻译效率和肌肉中胰岛素作用产生负面影响的机制。需要这样的数据才能充分发挥这类药物在长期治疗艾滋病毒感染方面的潜力并避免可能出现的陷阱。

DESCRIPTION (provided by applicant): This application is submitted in response to notice NOT-OD-09-058 (NIH Announces the Availability of Recovery Act Funds for Competitive Revision Applications) and requests a competitive supplement under ARRA 2009. Our parent grant has provided mechanism insight regarding the decrease in skeletal muscle protein synthesis produced by HIV-1 protease inhibitors such as indinavir and lopinavir (LPV). The long-term goal of the parent grant is to elucidate mechanisms by which LPV and other protease inhibitors produce muscle myopathy. While conducting the studies described in the parent application, we reported HIV-1 transgenic (Tg) rats, which are noninfectious and constitutively express 7 of 9 viral envelop proteins, exhibit muscle atrophy not attributable to decreased caloric intake or increased energy expenditure. We have now administered LPV to HIV-1 Tg rats for 3 months and the observed wasting was markedly greater than that seen in HIV-1 Tg rats without LPV. Furthermore, we have evidence that the co-existence of LPV and HIV-1 viral protein expression decreases muscle protein synthesis in the basal post-absorptive state. Finally, we also noted a marked glucose intolerance, insulin resistance and ectopic deposition of triglycerides in skeletal muscle of HIV-1 Tg rats administered LPV. Hence, it is clear there is a strong interaction between one or more the viral proteins (not the HIV-1 virus per se) and the protease inhibitor which produces a dramatic metabolic phenotype. It seems likely that examining the in vivo effects of protease inhibitors and other HAART drugs in the HIV-1 Tg rat provides a more clinically relevant model because of the drug-viral protein interaction. Therefore, the goal of this competing revision is to determine the mechanism by which the administration of LPV to HIV-1 Tg rats produces this complex metabolic phenotype - with the primary focus being on the changes in glucose and protein metabolism in muscle. Although related, such studies are beyond the direct scope of the parent grant. However, our provocative data warrant further investigation, and the proposed studies can be completed within a 2-yr period. This competing revision requests funds for four specific purposes: 1) Hiring an identified unemployed postdoctoral fellow; 2) employing a high school chemistry teacher as a summer intern; 3) purchase of HIV-1 Tg rats which are extremely expensive; and 4) purchase of supplies necessary for the fellow and intern to have a productive training environment and to successfully complete the designated studies within 2 years. Because the proposed studies were not part of the parent application sufficient unobligated funds are not available. We have been extremely productive during the initial years of the parent application, and the funds supplied in this competing revision will greatly accelerate our research in identifying the cellular and molecular basis for muscle atrophy and insulin resistance produced by protease inhibitors in HIV-infected individuals. PUBLIC HEALTH RELEVANCE: Muscle wasting and insulin resistance in those patients infected with HIV-1 often occur independent of AIDS and may be a direct result of the treatment of these individuals with HIV protease inhibitor drugs. Our studies using HIV-1 transgenic rats administered the commonly prescribed protease inhibitor lopinavir are designed to elucidate the mechanisms by which this class of drugs negatively impacts translational efficiency and insulin action in muscle. Such data are needed to both realize the full potential and avoid possible pitfalls of this drug class in long-term treatment of HIV infection.