The regulation of renal tubular transport by cannabinoid receptor type 1 (CB1R) and its endogenous lipid ligands

1型大麻素受体（CB1R）及其内源性脂质配体对肾小管转运的调节

• 批准号: 10588113
• 负责人: Joshua L Rein
• 金额: --
• 依托单位: JAMES J PETERS VA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-01 至 2028-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10588113
• 关键词: 2-arachidonylglycerol; Acids; Acute; Address; Adult; Affinity; Agonist; Aldosterone; Alkalies; American; Animal Model; Apical; Applications Grants; Arachidonic Acids; Bicarbonates; Biological; Board Certification; CNR1 gene; CNR2 gene; Cannabinoids; Cannabis; Cell Separation; Cell physiology; Cells; Cellular biology; Certification; Chronic Disease; Chronic Kidney Failure; Consumption; Coupled; Development; Development Plans; Dinoprostone; Disease; Distal; Diuresis; Diuretics; Duct (organ) structure; Educational workshop; Electrolytes; Electrophysiology (science); Elements; Endocannabinoids; Environment; Enzymes; Equilibrium; Esters; Excretory function; Exhibits; Exposure to; Fluid Balance; GLUT-2 protein; GTP-Binding Proteins; Genetic; Glucose; Goals; Homeostasis; Human; Hypertension; Hyponatremia; Impairment; In Vitro; Ingestion; Intercalated Cell; Investigation; Ion Transport; K ATPase; K-Series Research Career Programs; Kidney; Kidney Diseases; Knockout Mice; Knowledge; Leadership; Legal; Ligands; Limb structure; Lipid Biochemistry; Lipids; Liquid Chromatography; Measures; Mediating; Medicine; Mentors; Mentorship; Metabolic Pathway; Metabolic acidosis; Microdissection; Microscopy; Molecular; Monoacylglycerol Lipases; Mus; NAPE-PLD; Nephrons; Oryctolagus cuniculus; Osmosis; Output; Paracrine Communication; Pathway interactions; Perfusion; Persons; Pharmacology; Physiological; Physiology; Play; Population; Potassium; Property; Proteins; Proteinuria; Rattus; Receptor Activation; Receptor Signaling; Records; Recovery; Recreation; Recreational Drugs; Regulation; Renal Blood Flow; Reporting; Research; Rodent; Role; Signal Transduction; Sodium; Sodium Bicarbonate; Sodium Chloride; Sorting; Specialist; Testing; Therapeutic; Therapeutic Agents; Thick; Time; Training; Transcript; Transgenic Mice; Translating; Tubular formation; Urine; Veterans; Water; absorption; aged; anandamide; autocrine; base; cannabinoid receptor; career; career development; cyclooxygenase 2; endogenous cannabinoid system; fatty acid amide hydrolase; fetal; human disease; inhibitor; insight; kidney epithelial cell; kidney fibrosis; lipoprotein lipase; marijuana use; medical schools; mouse model; novel; novel therapeutics; paracrine; pharmacologic; phytocannabinoid; preclinical study; renal tubular transport; response; skills; success; tandem mass spectrometry; urinary; volume hypertension

PROJECT SUMMARY/ABSTRACT: Cannabis is the most commonly used federally illicit recreational drug in the U.S., and legal recreational and medicinal use has increased over the last decade. Cannabis contains phytocannabinoids with differing affinities for the ubiquitously expressed G-protein coupled cannabinoid receptors CB1R and CB2R. The kidney produces endogenous cannabinoids (ECs) that increase urine output with variable effects on Na+ and K+ excretion in rodents. Few studies in humans suggest that cannabinoids can act as diuretics, promoting not only urinary Na+ but alsoHCO3- losses. We have preliminarily shown in mice that CB1R is expressed in and impairs pHi regulation in intercalated cells (ICs), cells in the cortical collecting duct (CCD) that are responsible for H+/HCO3- secretion and Na+ (and K+) transport. We have also shown that cannabinoid receptor agonists acutely increase urinary water excretion in mice. Therefore, we hypothesize that ICs participate in CB1R mediated diuresis possibly through cross-talk with principal cells, cells responsible for the reabsorption of Na+ and water. This VA Career Development Award application aims to define the role of ECs in the CCD. Three Specific Aims (SA) will be studied to evaluate the presence and physiological significance of CB1R signaling on function of the mouse CCD. SA1 will define cell-specific expression of components of the EC system in this segment; SA2 will determine the role of CB1R signaling on cell-specific function in the CCD, utilizing pharmacologic activators/inhibitors of CB1R; and SA3 will determine whether targeted deletion of CB1R in ICs alters cell-specific functions. The results promise to provide new insight into the effects of cannabinoids on the kidney and allows us to identify targets (e.g., CB1R agonists) for development of novel therapeutic agents for the treatment of disorders such as hypertension, volume overload, metabolic acidosis, and hyponatremia. The proposed training plan includes career development activities, courses, and workshops to enhance the proficiency of the PI (Dr. Joshua Rein, a board-certified nephrologist and certified hypertension specialist) in single tubule microdissection, isolated tubule in vitro microperfusion, functional fluorescent microscopy, lipid biochemistry and pharmacology, cell biology, electrophysiology, cell sorting, and animal models including the development of transgenic mouse models. These skills will be reinforced by a team of mentors, advisors, and collaborators, all of whom have the requisite expertise, knowledge, and mentorship track-records. In sum, this VA CDA grant proposal provides a robust career development plan for Dr. Rein to accomplish his career goals to develop a national reputation as an expert in the renal EC system, aiming to uncover novel molecular pathways underlying the renal regulation of electrolyte and acid/base balance. His long-term goal is to translate key observations from preclinical studies into an enhanced understanding of human disease and therapeutics. The expertise and support of his mentors will be critical to his career development. The James J. Peters VAMC and the Icahn School of Medicine at Mount Sinai provide outstanding academic environments for Dr. Rein’s career development, with leadership committed to his success and 75% protected time conduct his research.

项目摘要/摘要： 大麻是美国最常用的联邦非法娱乐药物，也是合法的娱乐和娱乐药物 过去十年中药用有所增加。大麻含有具有不同亲和力的植物大麻素 普遍表达的 G 蛋白偶联大麻素受体 CB1R 和 CB2R。肾脏产生 内源性大麻素 (EC) 会增加尿量，对 Na+ 和 K+ 排泄产生不同影响 啮齿动物。很少有人类研究表明大麻素可以作为利尿剂，不仅促进尿 Na+ 还有HCO3-损失。我们已在小鼠中初步证明 CB1R 在 pHi 调节中表达并损害 pHi 调节 在闰细胞 (IC) 中，皮质集合管 (CCD) 中负责 H+/HCO3- 分泌的细胞 和Na+（和K+）运输。我们还表明，大麻素受体激动剂可急剧增加尿 小鼠的水排泄。因此，我们假设 ICs 可能参与 CB1R 介导的利尿 通过与主细胞（负责重吸收 Na+ 和水的细胞）的交互作用。 此 VA 职业发展奖申请旨在定义 EC 在 CCD 中的作用。三具体 将研究目标 (SA) 以评估 CB1R 信号传导对功能的存在及其生理意义 鼠标CCD。 SA1将定义该部分EC系统组件的细胞特异性表达； SA2 将利用药理学确定 CB1R 信号传导对 CCD 中细胞特异性功能的作用 CB1R 激活剂/抑制剂； SA3 将确定 IC 中 CB1R 的定向删除是否会改变细胞特异性 功能。研究结果有望为大麻素对肾脏的影响提供新的见解，并允许 我们确定靶点（例如 CB1R 激动剂），用于开发治疗以下疾病的新型治疗药物： 高血压、容量超负荷、代谢性酸中毒和低钠血症等疾病。 拟议的培训计划包括职业发展活动、课程和研讨会，以提高 PI（Joshua Rein 博士，委员会​​认证的肾病专家和认证的高血压专家）在以下方面的熟练程度 单肾小管显微解剖、离体肾小管体外微灌注、功能荧光显微镜、脂质 生物化学和药理学、细胞生物学、电生理学、细胞分选和动物模型，包括 转基因小鼠模型的开发。这些技能将通过导师、顾问和专家团队得到加强 合作者，他们都拥有必要的专业知识、知识和指导记录。 总之，这项 VA CDA 拨款提案为 Rein 博士提供了一个稳健的职业发展计划，以实现 他的职业目标是作为肾脏 EC 系统专家赢得全国声誉，旨在发现新颖的 肾脏调节电解质和酸/碱平衡的分子途径。他的长期目标是 将临床前研究的关键观察结果转化为对人类疾病和疾病的加深了解 疗法。导师的专业知识和支持对他的职业发展至关重要。詹姆斯·J. Peters VAMC 和西奈山伊坎医学院为 Rein 博士的职业发展，领导层致力于他的成功，75% 的受保护时间用于他的工作 研究。