Mechanisms of HIV Protease Inhibitor-Induced Lipid Dysregulation in Adipocytes

描述(由申请人提供)： 高效抗逆转录病毒疗法(HAART)的发展显著降低了HIV感染患者的发病率和死亡率，但该疗法也经常导致慢性代谢性疾病。 在接受HAART的患者中观察到的血脂异常、胰岛素抵抗和脂肪营养不良与HIV蛋白酶抑制剂(PI)有关。以前的研究表明，HIV Pis激活了内质网应激，内质网应激是巨噬细胞和肝细胞炎症反应和脂质代谢失调的基础。在脂肪细胞中，HIV Pis是体内脂肪储存和炎症的关键角色，已被证明激活内质网应激，增加促炎细胞因子的分泌，改变脂代谢，并抑制前脂肪细胞向成熟脂肪细胞的分化。然而，HIV Pl诱导的细胞调节失调的细胞机制尚不清楚。我们假设HIV P通过激活脂肪细胞中的内质网应激和炎症反应来扰乱脂代谢。我们将通过三个具体目标来检验这一假设。目的1阐明HIV Pl诱导脂肪细胞内质网应激的机制。我们将通过研究前期和分化的小鼠以及人类培养的脂肪细胞中蛋白质和mRNA水平的变化来实现这一点。目的2确定内质网应激在HIV Pl诱导的脂肪细胞脂代谢紊乱和诱导炎症反应中的作用。我们将首先关注HIV Pis在这些过程中的影响，然后破坏ER应激途径的关键角色，以测试这些影响是如何改变的。目的3研究HIV Pl诱导的巨噬细胞细胞因子分泌在脂肪细胞内质网应激激活、细胞因子分泌和脂肪组织炎症中的作用。我们将处理巨噬细胞和脂肪细胞的共培养，以分析UPR激活和细胞因子分泌与单独培养和处理的细胞的差异。我们将通过体外研究来确定HIV PI治疗对脂肪组织炎症的影响程度。通过了解HIV Pis如何扰乱代谢性疾病关键细胞的正常功能，我们可以学习通过在HIV患者中使用HAART的同时替代疗法来预防这些疾病的发生。 公共卫生相关性：HAART诱导的血脂异常和脂肪营养不良是A 用于治疗艾滋病毒感染者的关键药物方案。确定其中一些药物导致破坏性代谢性疾病的潜在细胞/分子机制，可以让我们开发新的治疗方法，抵消这些慢性病的诱导。

DESCRIPTION (provided by applicant): The development of highly active antiretroviral therapy (HAART) has significantly reduced morbidity and mortality in HIV-infected patients, yet the regimen also often results in chronic metabolic diseases. Dyslipidemia, insulin resistance, and lipodystrophy observed in patients receiving HAART have been linked to HIV protease inhibitors (PI). Previous studies have shown that HIV Pis activate ER stress, which underlies inflammatory responses and dysregulation of lipid metabolism in macrophages and hepatocytes. Within adipocytes, key players in both body lipid storage and inflammation, HIV Pis have been shown to activate ER stress, increase proinflammatory cytokine secretions, alter lipid metabolism, and inhibit differentiation of pre-adipocytes to mature adipocytes. Yet, the cellular mechanisms of HIV Pl-induced dysregulations have not been elucidated. We hypothesize that HIV Pis disrupt lipid metabolism by activating ER stress and inflammatory responses in adipocytes. We will test this hypothesise through three specific aims. AIM 1 is to elucidate the mechanism of HIV Pl-induced ER stress in adipocytes. We will accomplish this by studying protein and mRNA level changes in pre- and differentiated murine, as well as human, cultured adipocytes. AIM 2 is to define the role of ER stress in HIV Pl-induced dysregulation of adipocyte lipid metabolism and induction of the inflammatory response. We will first focus on the effects of HIV Pis in these processes and then knock down key players of the ER stress pathway to test how these effects are altered. Aim 3 is to characterize the contribution of HIV Pl-induced macrophage cytokine secretions play in adipocyte ER stress activation, adipocyte cytokine secretion, and adipose tissue inflammation. We will treat co-cultures of macrophages and adipocytes to analyze differences in UPR activation and cytokine secretions versus cells cultured and treated alone. We will follow this by in vitro studies to determine the extent HIV PI treatment has on adipose tissue inflammation. By understanding how HIV Pis disrupt normal function in key cells of metabolic disease, we can learn to prevent the onset of these diseases by using concurrent alternative therapies with HAART in HIV patients. Public Health Relevance: HAART-induced dylipidemia and lipodystrophy are two major side effects of a pivotal drug regimen used for treating HIV-infected patients. Determining the underlying cellular/molecular mechanisms by which some of these drugs cause devastating metabolic diseases can allow us to develop new therapies that will counteract induction of these chronic illnesses.