Novel Reengineered Microbiome-based Biologic Therapy to Treat Cognitive and Behavioral Symptoms of Alzheimer's Disease and Related Dementias

摘要 我们的早期ADDP提案旨在开发一种新的基因工程细菌生物学来治疗 阿尔茨海默病(AD)最常见的早期症状，包括认知障碍和其他 神经心理症状，如焦虑和抑郁。这种令人衰弱的疾病给人们带来了巨大的 给社会带来情感、社会和经济负担。目前尚无有效的治疗阿尔茨海默病的药物 与疾病进展相关的β和tau蛋白病变。目前FDA批准的胆碱能和 谷氨酸能神经疗法在挽救轻度认知障碍(MCI)的记忆方面充其量是非常温和的 和先兆或早期阿尔茨海默病病例，并经常恶化焦虑，冷漠，抑郁，激越等 神经行为症状，胃肠道刺激，甚至死亡。最近的生物学证据表明，阿尔茨海默病是一种 神经回路紊乱。认知和行为症状的发生和发展涉及到 单胺类神经递质信号网络，包括去甲肾上腺素(NE)和多巴胺(DA)。因此，我们 认为恢复脑DA/NE传入具有良好的潜力，是一种有效的缓解 阿尔茨海默病的认知和行为缺陷，甚至可能推迟疾病的发病。目前，L口服片剂-- 在恢复人类大脑DA/NE水平方面，多巴/卡比多巴每天3-4次仍然是最有效的治疗方法。 然而，这种反复的慢性脉冲式分娩会产生严重的副作用。因此，我们的治疗假设 要解决这一未解决的临床问题，基因工程L-多巴细菌的系统输送是一种有效的治疗方法。 治疗公司将避免血浆L-多巴的大幅波动，并提供更一致的L- 多巴给大脑，使DA/NE恢复到稳定水平，更好地缓解AD症状，而无需额外的副作用 效果。我们的概念验证数据支持1)基因工程益生菌E.ColiNissle 1917菌株 (EcNL-DOPA)在体外和体内都能高效地产生L-DOPA，2)口服ECNL-DOPA容易在体内定植 小鼠肠道，达到与临床有效血浆相对应的稳态血浆L-多巴水平 并增加啮齿动物和犬脑组织中L-多巴和DA/NE的水平，以及3)EchNL-多巴 治疗可改善AD动物模型的神经行为结果并降低Aβ水平，包括 犬科动物。我们正在申请专利的ADDP战略的首要目标是优化Lead LDBL和测试 它在缓解早期AD的认知和行为缺陷方面的临床前疗效，如冷漠。 为了实现这一目标，我们将追求以下具体目标：(I)优化用于动物试验的主导低密度脂蛋白，(Ii) 评估用于临床前疗效研究的铅低密度脂蛋白的慢性药代动力学(PK)和安全性 (Iii)测定两种铅低密度脂蛋白在转基因AD模型中的体内药效学(PD)效果， 以及(Iv)评估最有效的低密度脂蛋白铅对犬痴呆模型的疗效。在一起，我们独一无二的 益生菌L-多巴慢性给药治疗流水线战略有望建立新线 以工程微生物组为基础的单胺类神经疗法治疗AD相关痴呆(ADRD)。

Abstract Our early-stage ADDP proposal aims to develop a novel genetically engineered bacterial biologic to treat the most common early symptoms of Alzheimer's disease (AD), including cognitive impairment and other neuropsychological symptoms, such as anxiety and depression. This debilitating disease imposes a huge emotional, social and financial burden on society. No effective disease-modifying AD drug exists to dampen the Aβ and tau proteinopathies associated with disease progression. Current FDA-approved cholinergic and glutamatergic neurotherapeutics are very modest at best in rescuing memory in mild cognitive impairment (MCI) and prodromal or early stages of AD cases, and often worsen anxiety, apathy, depression, agitation, and other neurobehavioral symptoms, GI irritations, and even mortality. Recent biological evidence indicates that AD is a neural circuit disorder. The onset and progression of cognitive and behavioral symptoms involve a deficiency in monoamine neurotransmitter signaling networks, including norepinephrine (NE) and dopamine (DA). Thus, we propose that restoring brain DA/NE inputs holds the excellent potential to be an effective approach to alleviating cognitive and behavioral deficits in AD and could even delay disease onset. Currently, oral tablet dosing of L- DOPA/carbidopa 3-4 times/day remains the most effective therapy at restoring brain DA/NE levels in humans. However, this repeated chronic pulsatile delivery causes severe side effects. Thus, our therapeutic hypothesis to address this unmet clinical problem is that systemic delivery of genetically engineered L-DOPA bacterial live- therapeutics (LDBL) will avoid large fluctuations in plasma L-DOPA and provide more consistent delivery of L- DOPA to the brain for restoring DA/NE to stable levels that better relieve AD symptoms without additional side effects. Our proof-of-concept data support that 1) the genetically engineered probiotic E. coli Nissle 1917 strains (EcNL-DOPA) efficiently produce L-DOPA both in vitro and in vivo, 2) oral dosing of EcNL-DOPA readily colonizes the mouse gut, achieves a steady-state plasma L-DOPA level that corresponds to the clinically effective plasma level in humans, and increases L-DOPA and DA/NE levels in the brain of rodents and canines, and 3) EcNL-DOPA treatment leads to improved neurobehavioral outcomes and reduces Aβ levels in AD animal models including canines. The overarching goal of our patent-pending ADDP strategy is to optimize the lead LDBL and test its preclinical efficacy in alleviating the cognitive and behavioral deficits, such as apathy, of early AD. To achieve this goal, we will pursue the following specific aims: (i) Optimize the lead LDBL for animal testing, (ii) Evaluate the chronic pharmacokinetic (PK), and safety profile of the lead LDBLs for preclinical efficacy studies, (iii) Determine in vivo pharmacodynamic (PD) efficacy of two lead LDBLs in transgenic (Tg) AD rodent models, and (iv) Assess the efficacy of the most effective lead LDBL in canine models of dementia. Together, our unique therapeutic pipeline strategy involving chronic delivery of probiotic L-DOPA is expected to establish a new line of engineered microbiome-based monoamine neurotherapeutic modalities for AD-related dementias (ADRD).