Investigations of Methylmalonic Acidemia and Related Disorders

甲基丙二酸血症及相关疾病的调查

• 批准号: 8750680
• 负责人: Charles P Venditti
• 金额: $ 145.7万
• 依托单位: NATIONAL HUMAN GENOME RESEARCH INSTITUTE
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/8750680
• 关键词: Adult; Affect; Albumins; Antioxidants; Attenuated; Basal Ganglia; Biochemical; Biological Markers; Biopsy; Chronic; Chronic Kidney Failure; Clinic; Clinical; Clinical Protocols; Clinical Research; Cobalamin; Complex; Data; Defect; Development; Developmental Delay Disorders; Diabetes Mellitus; Diet; Dietary Intervention; Disease; Dose; Effectiveness; End stage renal failure; Enrollment; Enzymes; Evaluation; Extramural Activities; Foundations; Functional disorder; Funding; Future; Genes; Genetic; Genets; Genomics; Glomerular Filtration Rate; Goals; Grant; Growth; Guidelines; Hepatic; Hepatocyte; Human; Hydrops Fetalis; Impairment; Inborn Errors of Metabolism; Inherited; Intervention; Investigation; Kidney; Kidney Diseases; Kidney Failure; Knock-out; Laboratories; Lead; Length; Lesion; Link; Liver; Manuscripts; Measurement; Medical; Metabolic; Metabolic Diseases; Metabolism; Methylmalonyl-CoA Mutase; Microarray Analysis; Mitochondria; Modeling; Monitor; Mus; Mutase; Mutation; Myocardium; National Human Genome Research Institute; Natural History; Nature; Neonatal; Nephritis; Nephrons; Neurologic; Newborn Infant; Nutritional; Obesity; Organ Transplantation; Osteoporosis; Pancreas; Pancreatitis; Pathology; Pathway interactions; Patient Care; Patients; Pharmaceutical Preparations; Phenotype; Physiology; Proteins; Proteomics; Publishing; Renal function; Research; Solid; Stress; Stroke; Syndrome; Therapeutic Intervention; Therapeutic Studies; Transgenes; Transgenic Organisms; Translating; Translational Research; Translations; Tubular formation; United States National Institutes of Health; Ventricular; Vitamin B 12 Deficiency; Vitamin E; adeno-associated viral vector; antioxidant therapy; bench to bedside; clinical efficacy; clinical phenotype; cofactor; cohort; design; evidence base; experience; expression vector; gene therapy; host cell factor C1; human subject; in vivo; insight; metabolic abnormality assessment; metabolomics; methylmalonic aciduria; mitochondrial dysfunction; mouse model; novel; oxidation; patient population; pre-clinical; preclinical study; programs; promoter; propionyl-coenzyme A; research study; response; screening; stable isotope; success; ubiquinol; vector

The clinical characterization of patients with methylmalonic acidemia (MMA) and related disorders, will continue via a dedicated natural history study, NHGRI protocol Clinical and Basic Investigations of Methylmalonic Acidemia and Related Disorders (ClinicalTrials.gov Identifier: NCT00078078), which has enrolled the largest such patient cohort in the world. In the past year, we have focused on the clinical study of MMA related kidney disease, both in the clinic and laboratory. With more aggressive treatment of MMA, long-term complications, particularly chronic kidney disease and renal failure, are becoming more apparent in the surviving patient population. We prospectively assessed renal length, anthropometric measurements, and laboratory evaluations in our large cohort of carefully characterized patients with isolated MMA (Kruszka PS, Manoli I, Sloan JL, Kopp JB, Venditti CP (2013) Renal growth in isolated methylmalonic acidemia. Genet Med, in press). We found that renal length in MMA patients, reflective of kidney growth, was significantly decreased compared to normal controls and derived a multiple regression model to predict kidney growth. In addition to providing the first detailed description of the renal phenotype seen in patients with MMA, this manuscript established a foundation to evaluate renoprotective interventions and their effects on kidney growth and function in the MMA patient population. We have also described an unusual presentation of cblC deficiency as non-immune fetal hydrops (Tanpaiboon P, Sloan JL, Callahan PF, McAreavey D, Hart PS, Lichter-Konecki U, Zand D, Venditti CP (2013) Noncompaction of the ventricular myocardium and hydrops fetalis in cobalamin C disease. JIMD Rep 10:33-8), participated in a review of nutritional management for metabolic disorders, including MMA (Camp KM, et al., (2013) Expanding research to provide an evidence base for nutritional interventions for the management of inborn errors of metabolism. Mol Genet Metab 109:319-28) and participated in the identification of a novel inborn error of metabolism, cblX (Yu H.C., et al., (2013) Mutations in HCFC1 a transcriptional coregulator causes a novel X-linked cobalamin disorder (cblX) with a severe neurological phenotype. Am J Hum Gen. (in press). Active clinical efforts include the characterization of MMA patients who have received solid organ transplantation, neuroradiographic and spectroscopic studies on the MMA stroke syndrome, delineation of the ophthalmological manifestations of MMA and cobalamin disorders, the development of evidence-based dietary guidelines, and definition of the clinical phenotype of CMAMMA. A collaborative intra- and extramural Bench to Bedside grant with Dr Mendel Tuchman (CNMC) to fund our studies using stable isotopes in MMA patients (Metabolic Phenotyping in Methylmalonic Acidemia: Markers and Drug Response (2012-2014) will continue during the next FY. Laboratory investigations have focuses on generating and characterizing mouse models of methylmalonic acidemia and gene therapy studies. Modeling of MMA renal disease in mice has recently been accomplished and correlated with patient findings (Manoli I, Sysol JR, Li L, Houillier P, Garone C, Wang C, Zerfas PM, Cusmano-Ozog K, Young S, Trivedi NS, Cheng J, Sloan JL, Chandler RJ, Abu-Asab M, Tsokos M, Elkahloun AG, Rosen S, Enns GM, Berry GT, Hoffmann V, Dimauro S, Schnermann J, Venditti CP (2013) Targeting proximal tubule mitochondrial dysfunction attenuates the renal disease of methylmalonic acidemia. Proc Natl Acad Sci U S A 110:13552-7). Using the patient experience to guide mouse modeling efforts, a viable model of MMA renal disease was generated by expressing methylmalonyl-CoA mutase (Mut) as a stable transgene in hepatocytes under the control of an albumin (INS-Alb-Mut) promoter. Mut-/-;TgINS-Alb-Mut mice, while completely rescued from neonatal lethality, manifested a decreased glomerular filtration rate (GFR), chronic tubulointerstital nephritis (CTIN) and ultrastructural changes in the proximal tubule mitochondria that were precisely replicated in kidney biopsies from our NIH MMA patients. Moreover, renal physiology studies at the single nephron level were conducted to precisely characterize the nature of the defect and establish that the early and marked reduction of GFR is initiated by proximal tubular mitochondrial dysfunction. Microarray analysis using Mut-/-;TgINS-Alb-Mut kidneys identified numerous biomarkers, including lipocalin-2 (Lcn2), which were validated as associated with renal function in the large NIH MMA patient population. Using the insights from the mouse model and the supporting data from our clinical cohort, we designed a therapeutic study to monitor the response of the GFR to antioxidant therapy in the Mut-/-;TgINS-Alb-Mut mice by inducing the kidney disease with a high protein diet to stress the propionyl-CoA oxidation pathway, with and without vitamin E and ubiquinol in the chow. We demonstrated that the inclusion of antioxidants in the diet could substantially ameliorate the loss of the GFR in the mouse model, establishing the first rational treatment for kidney disease in MMA patients. This study provides the pre-clinical foundation for a future human subjects trial. In the next year, we will continue to create and characterize additional murine models that have an physiologically apparent intermediate or inducible phenotype yet are robust to allow the assessment of gene therapy approaches and the exploration of pathophysiological mechanisms. We will then characterize the disease state using genomic, proteomic and metabolomic approaches to define mechanisms and identify biomarkers that might be translated to patient care. Other than routine dietary and cofactor therapy, no alternative to organ transplantation exists for patients with these inborn errors of metabolism. The successful demonstration of gene therapy for MMA is certain to provide precedence to treat many other disorders of intermediary metabolism, particularly those that feature mitochondrial localization of the metabolic lesion, using a similar approach. Building upon our success with various adeno-associated viral (AAV) vectors to deliver the murine methylmalonyl-CoA mutase gene, we have created new AAVs suitable for potential translation to humans. One affords ubiquitous expression of the human MUT enzyme and another directs hepatic expression. The ubiquitous expression vector has been studied in Mut-/- mice and dose reduction studies have established the minimum dose needed to rescue mice that display a neonatal lethal phenotype. A manuscript detailing these findings has been published (Chandler RJ, Venditti CP (2012) Pre-clinical efficacy and dosing of an AAV8 vector expressing human methylmalonyl-CoA mutase in a murine model of methylmalonic acidemia (MMA). Mol Genet Metab 107:617-9), while experiments to characterize the liver specific expression cassette are ongoing. We will continue to determine the most effective dose and AAV vector for efficient gene therapy in a variety of MMA mouse models, including new transgenic knock-out models. Analysis of the effectiveness of each vector will use growth, metabolic, biochemical, expression and in vivo metabolic studies to determine the degree of correction achieved. It is anticipated that such pre-clinical studies will lead to the creation of an optimal vector for use in humans, affording an opportunity to pursue an IND submission to the FDA as a step toward translating gene therapy to the clinic.

甲基丙二酸血症 (MMA) 和相关疾病患者的临床特征将通过专门的自然史研究、NHGRI 方案甲基丙二酸血症和相关疾病的临床和基础研究（ClinicalTrials.gov 标识符：NCT00078078）继续进行，该研究已招募了世界上最大的此类患者队列。在过去的一年里，我们重点关注MMA相关肾脏疾病的临床研究和实验室研究。随着 MMA 治疗更加积极，长期并发症，特别是慢性肾病和肾衰竭，在幸存的患者群体中变得越来越明显。我们对大型孤立性 MMA 患者进行了前瞻性评估，包括肾长度、人体测量和实验室评估（Kruszka PS、Manoli I、Sloan JL、Kopp JB、Venditti CP (2013) 孤立性甲基丙二酸血症中的肾生长。Genet Med，出版中）。我们发现，与正常对照相比，MMA 患者的肾脏长度（反映肾脏生长）显着缩短，并得出了预测肾脏生长的多元回归模型。除了首次详细描述 MMA 患者的肾脏表型外，该手稿还为评估 MMA 患者群体的肾脏保护干预措施及其对肾脏生长和功能的影响奠定了基础。 我们还描述了 cblC 缺乏症的一种异常表现，即非免疫性胎儿水肿（Tanpaiboon P、Sloan JL、Callahan PF、McAreavey D、Hart PS、Lichter-Konecki U、Zand D、Venditti CP (2013) 钴胺素 C 病中心室心肌致密化和胎儿水肿。JIMD 代表 10:33-8)，参与了代谢性疾病营养管理的综述，包括 MMA (Camp KM, et al., (2013) Expanding Research to Provide a循证基础，为管理先天性代谢缺陷的营养干预提供证据基础。Mol Genet Metab 109:319-28) 并参与了一种新型先天性代谢缺陷 cblX 的鉴定 (Yu H.C., et al., al., (2013) 转录共调节因子 HCFC1 的突变导致一种新型 X 连锁钴胺素障碍 (cblX)，具有严重的神经表型。 Am J Hum Gen.（正在出版）。 积极的临床工作包括接受实体器官移植的 MMA 患者的特征分析、MMA 中风综合征的神经放射学和光谱研究、MMA 和钴胺素疾病的眼科表现的描述、循证饮食指南的制定以及 CMAMMA 临床表型的定义。与 Mendel Tuchman 博士 (CNMC) 合作的校内和校外床边拨款资助我们在 MMA 患者中使用稳定同位素进行的研究（甲基丙二酸血症的代谢表型：标记物和药物反应（2012-2014））将在下一个财政年度继续进行。 实验室研究的重点是生成和表征甲基丙二酸血症小鼠模型和基因治疗研究。最近已经完成了小鼠 MMA 肾病的建模，并与患者的发现相关联（Manoli I、Sysol JR、Li L、Houillier P、Garone C、Wang C、Zerfas PM、Cusmano-Ozog K、Young S、Trivedi NS、Cheng J、Sloan JL、Chandler RJ、Abu-Asab M、Tsokos M、Elkahloun AG、Rosen S、 Enns GM、Berry GT、Hoffmann V、Dimauro S、Schnermann J、Venditti CP (2013) 针对近端小管线粒体功能障碍可减轻甲基丙二酸血症的肾脏疾病。美国国家科学院院刊 110:13552-7）。利用患者经验指导小鼠建模工作，通过在白蛋白 (INS-Alb-Mut) 启动子控制下将甲基丙二酸单酰辅酶 A 变位酶 (Mut) 作为稳定转基因在肝细胞中表达，生成了可行的 MMA 肾病模型。 Mut-/-;TgINS-Alb-Mut 小鼠虽然完全免于新生儿致死，但表现出肾小球滤过率 (GFR) 降低、慢性肾小管间质性肾炎 (CTIN) 和近端小管线粒体超微结构变化，这些变化在我们的 NIH MMA 患者的肾活检中精确复制。此外，在单个肾单位水平上进行肾脏生理学研究，以精确表征缺陷的性质，并确定 GFR 的早期显着降低是由近端肾小管线粒体功能障碍引起的。使用 Mut-/-;TgINS-Alb-Mut 肾脏的微阵列分析确定了许多生物标志物，包括 lipocalin-2 (Lcn2)，这些生物标志物已被验证与大量 NIH MMA 患者群体的肾功能相关。利用小鼠模型的见解和我们临床队列的支持数据，我们设计了一项治疗研究，通过高蛋白饮食诱导肾脏疾病来应激丙酰辅酶A氧化途径，并在食物中添加或不添加维生素E和泛醇，从而监测Mut-/-;TgINS-Alb-Mut小鼠的GFR对抗氧化治疗的反应。我们证明，在小鼠模型中，在饮食中添加抗氧化剂可以显着改善 GFR 的损失，从而为 MMA 患者的肾脏疾病建立了第一个合理的治疗方法。这项研究为未来的人体试验提供了临床前基础。 明年，我们将继续创建和表征其他小鼠模型，这些模型具有生理上明显的中间或可诱导表型，但又足够强大，可以评估基因治疗方法和探索病理生理机制。然后，我们将使用基因组学、蛋白质组学和代谢组学方法来表征疾病状态，以定义机制并识别可能转化为患者护理的生物标志物。 对于患有这些先天性代谢缺陷的患者来说，除了常规饮食和辅因子治疗之外，没有其他替代器官移植的方法。 MMA 基因治疗的成功示范肯定会为许多其他中间代谢疾病的治疗提供先例，特别是那些以代谢病变线粒体定位为特征的疾病，使用类似的方法。基于我们成功地使用各种腺相关病毒 (AAV) 载体传递小鼠甲基丙二酸单酰辅酶 A 变位酶基因，我们创建了适合潜在翻译给人类的新 AAV。一种提供人类 MUT 酶的普遍表达，另一种指导肝脏表达。这种普遍存在的表达载体已在 Mut-/- 小鼠中进行了研究，剂量减少研究已经确定了拯救表现出新生儿致死表型的小鼠所需的最低剂量。详细介绍这些发现的手稿已发表（Chandler RJ, Venditti CP (2012) Pre-clinical功效和剂量的AAV8载体在甲基丙二酸血症（MMA）的小鼠模型中表达人甲基丙二酸单酰辅酶A变位酶。Mol Genet Metab 107:617-9），同时正在进行表征肝脏特异性表达盒的实验。我们将继续确定最有效的剂量和 AAV 载体，以在各种 MMA 小鼠模型（包括新的转基因敲除模型）中进行有效的基因治疗。对每个载体的有效性分析将利用生长、代谢、生化、表达和体内代谢研究来确定所实现的校正程度。预计此类临床前研究将导致创建用于人类的最佳载体，并提供向 FDA 提交 IND 的机会，作为将基因疗法转化为临床的一步。