Role of Gut Microbiome in HIV/Opioid Induced Peripheral Neuropathy

项目摘要 长期使用阿片类药物导致非典型疼痛（痛觉过敏）的矛盾增加。尽管其知名 由于其局限性，阿片样物质诱导的痛觉过敏的潜在机制仍然是一个显着的知识空白。 周围神经病变已成为HIV患者最常见的神经系统并发症， 在感染患者中高达69.4%，值得注意的是，HIV感染的阿片类药物滥用者似乎表现出更严重的 比感染艾滋病毒的非吸毒者神经病变。此外，据报告，重复使用阿片类镇痛剂 促进HIV患者的神经性疼痛。很少有人知道ART是否会导致周围神经病变， 它在长期阿片类药物使用者中加剧。吗啡及其衍生物的主要代谢途径 在哺乳动物中，是由UDP-葡萄糖醛酸转移酶（UGT）催化的葡萄糖醛酸化。吗啡是 主要代谢为两种代谢产物，吗啡-3-葡糖苷酸（M3 G）和吗啡-6-葡糖苷酸 (M6G)（1，2）。M-3-G是啮齿类动物中产生的唯一代谢物，不具有任何镇痛作用，但具有 在最近的研究中显示激活和调节TLR信号传导。此外，抗逆转录病毒药物 特别是整合酶抑制剂，也通过UGT-葡萄糖醛酸化途径代谢。最近 研究表明，整合酶抑制剂齐多夫定的代谢产物比母体毒性更大， 化合物.在初步数据中，我们表明，慢性吗啡治疗导致显著的肠道微生物 生态失调，合成β-葡萄糖醛酸酶的细菌群落显著减少，同时 葡萄糖醛酸酶活性降低。我们在初步数据中表明，细菌群落的消耗 a）肠和血清中M-3-G积累增加 和B）减少吗啡的肠肝再循环。我们进一步证明，吗啡治疗在 HIV感染的背景导致机械性异常性疼痛（Von Frey）和 热痛觉过敏试验（Hargraves）。促炎细胞因子水平和吗啡诱导的 在TLR 2敲除小鼠中痛觉过敏显著减弱。基于这些观察，我们假设 这减少了与β葡萄糖醛酸酶合成相关的微生物群落， 暴露于高剂量吗啡会导致M-3-G吗啡代谢物累积并产生毒性 小肠中葡萄糖醛酸化ART有助于特定目标1：确定 吗啡代谢物M-3-葡萄糖醛酸苷在肠道中导致阿片样物质诱导的痛觉过敏和HIV诱导的痛觉过敏。 使用阿片类药物的HIV患者的周围神经病变。具体目标2：确定TLR 2信号传导在 在ART治疗的背景下，吗啡诱导的痛觉过敏和HIV相关的周围神经病变。 具体目的3：用具有B-的受控表达的基因工程化的大肠杆菌治疗 葡萄糖醛酸酶与TLR 2/4拮抗剂组合将保持小肠屏障完整性并减弱 周围神经病变和延长吗啡镇痛。

Project Summary Prolonged use opioids results in a paradoxical increase in atypical pain (hyperalgesia). Despite its known limitations, mechanisms underlying opioid-induced hyperalgesia still remains a significant gap in knowledge. Peripheral neuropathy has become the most common neurologic complication in HIV patients, with prevalence as high as 69.4% in infected patients, Notably, HIV-infected opioid abusers appear to exhibit more severe neuropathy than HIV-infected non-drug users. Furthermore, repeated use of opioid analgesics are reported to promote neuropathic pain in HIV patients. Very little is known if ART contributes to peripheral neuropathy and if it is exacerbated in chronic opioid users. The main metabolic pathway for morphine and morphine derivatives in mammals is glucuronidation catalyzed by UDP-glucuronosyltransferase (UGT) enzymes. Morphine is metabolized predominantly to two metabolites, morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) (1,2). M-3-G is the only metabolite produced in rodents and does not have any analgesic effects but have been shown in recent studies to activate and modulate TLR signaling. Furthermore, antiretroviral drugs particularly, intergrase inhibitors, are also metabolized through the UGT- glucuronidation pathway. Recent studies show that the metabolites of the intergrase inhibitor zidovudine to be more toxic than the parent compound. In preliminary data we show that chronic morphine treatment results in significant gut microbial dysbiosis with significant decrease in bacterial communities that synthesize β-glucuronidase with a concurrent decrease in glucuronidase activity. We show in preliminary data that depletion in the bacterial communities involved in the synthesis of β -glucuronidase results in a) increased accumulation M-3-G in the gut and serum and b) reduced enterohepatic recycling of morphine. We further demonstrate that morphine treatment in the context of HIV infection results in significant hyperalgesia in the both the Mechanical allodynia (Von Frey) and Thermal hyperalgesia test (Hargraves) tests. Proinflammatory cytokine levels and morphine induced hyperalgesia are significantly attenuated in TLR2 knock out mice. Based on these observations we hypothesize that decreased microbial communities associated with β glucuronidase synthesis following prolonged exposure to high dose morphine results in accumulation of M-3-G morphine metabolite and toxic glucuronidated ART in the small intestine contributing to Specific Aim 1: Establish that accumulation of the morphine metabolite M-3-glucoronide in the gut results in opioid induced hyperalgesia and HIV induced peripheral neuropathy in opiod using HIV patients. Specific Aim 2: Determine the role of TLR2 signaling in morphine induced hyperalgesia and HIV associated peripheral neuropathy in the context of ART treatment. Specific Aim 3: Treatment with genetically engineered commensal bacteria with controlled expression of B- glucuronidase in combination with TLR2/4 antagonist will preserve small intestinal barrier integrity and attenuate peripheral neuropathy and prolong morphine analgesia.