Blockade of miR-29b-1-5p promotes MSC-mediated bone regeneration during aging

阻断 miR-29b-1-5p 可促进衰老过程中 MSC 介导的骨再生

• 批准号: 8783881
• 负责人: Samuel Herberg
• 金额: $ 5.23万
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-01 至 2017-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8783881
• 关键词: Address; Adult; Age; Age-Related Bone Loss; Aging; Biocompatible Materials; Biological Assay; Biomedical Engineering; Bone Injury; Bone Regeneration; COL1A1 gene; CXCR4 gene; Calvaria; Cellular biology; Characteristics; Clinical; Complex; Data; Defect; Degenerative polyarthritis; Development; Disease; Elderly; Encapsulated; Enzyme-Linked Immunosorbent Assay; Epidemic; Exhibits; Family; Foundations; Gene Expression; Gene Targeting; Genetic Translation; Healed; Health; Human; Hydrogels; Impaired wound healing; In Vitro; Individual; Injury; Intervention; Luciferases; Mediating; Mesenchymal; Mesenchymal Differentiation; MicroRNAs; Modeling; Molecular; Musculoskeletal System; Natural regeneration; Osteogenesis; Osteoporosis; Patients; Phenotype; Play; Polymers; Population; Process; Rattus; Regulator Genes; Reporter; Role; Signal Pathway; Signal Transduction; Sister; Staining method; Stains; Stromal Cell-Derived Factor 1; Stromal Cells; System; Therapeutic; Therapeutic Effect; Time; Tissues; Transcript; Untranslated Regions; Western Blotting; age related; aged; base; biodegradable polymer; biomaterial compatibility; bone; effective therapy; healing; improved; in vitro Assay; in vivo; inhibitor/antagonist; member; novel; osteogenic; osteoporosis with pathological fracture; pre-clinical; promoter; regenerative; skeletal injury; stem; treatment effect

DESCRIPTION (provided by applicant): A large body of evidence suggests that bone is a dynamic tissue that can heal spontaneously following injury. However, this regenerative process often fails in the geriatric population contributing to widespread aging- related injuries to the musculoskeletal system. Inhibition of mRNA translation by microRNAs (miRNAs) has emerged as an important regulator of osteogenic signaling pathways. Accordingly, miRNA dysregulation has been implicated in the onset and progression of osteoporosis and osteoarthritis. These findings provide a rational basis for the development of novel bone bioengineering therapies that target specific miRNAs in a spatially and temporally controlled fashion. Among its members, miR-29b-1-3p is considered a mature dominant miRNA species that facilitates osteogenic differentiation of human mesenchymal stem/stromal cells (MSCs). In contrast, little is known about miR-29b-1-5p, the other mature miRNA expressed from the same precursor, which until recently was thought of as a byproduct. We have preliminary evidence that miR-29b-1- 5p is anti-osteogenic and that MSCs isolated from geriatric patients exhibit elevated levels of miR-29b-1-5p compared to adult MSCs, while the expression of miR-29b-1-3p is unchanged. These novel findings suggest a pathogenic role for miR-29b-1-5p in aging-related defects in osteogenesis and bone regeneration. Based on these findings, we hypothesize that the miR-29b-1-5p/miR-29b-1-3p ratio increases with age thereby tilting the scale towards anti-osteogenic characteristics. We further hypothesize that inhibitors of miR-29b-1-5p (anti- miRNA therapy) would be effective in reversing anti-osteogenic effects and promoting bone regeneration with progressing age. In this proposal, we aim to elucidate the molecular basis by which miR-29b-1-5p suppresses osteogenic gene targets and disrupts osteogenic differentiation of MSCs with aging, and to determine the effects of altering miR-29b-1-5p levels on MSC-mediated local bone formation in vivo using novel polymer hydrogels. To address these aims, we will use a variety of molecular cell biology and functional assays prior to employing an established orthotopic bone injury model. These studies will provide preclinical evidence for the therapeutic potential of miR-29b-1-5p inhibitors to promote bone regeneration and also for an effective and improved delivery system for anti-miRNA therapy.

描述（由申请人提供）：大量证据表明骨骼是一种动态组织，可以在受伤后自发治愈。但是，这种再生过程通常在老年人群中失败，导致对肌肉骨骼系统的广泛衰老损伤。 microRNA（miRNA）对mRNA翻译的抑制已成为成骨信号通路的重要调节剂。因此，miRNA失调与骨质疏松和骨关节炎的发作和进展有关。这些发现为开发新型骨骼生物工程疗法的发展提供了合理的基础，该疗法以空间和时间控制的方式靶向特定的miRNA。在其成员中，miR-29b-1-3p被认为是成熟的主要miRNA物种，可促进人间质茎/基质细胞（MSC）的成骨分化。相比之下，关于miR-29b-1-5p的知之甚少，另一个成熟的miRNA是从同一前代表达的，直到最近才被认为是副产品。我们有初步证据表明，与成人MSC相比，从老年患者中分离出的MiR-29b-1-5p是抗肌生成的，而从老年患者中分离出的MiR-29b-1-5p水平升高，而miR-29b-1-3p的表达不变。这些新的发现表明，在成骨和骨再生中，miR-29b-1-5p在与衰老相关的缺陷中具有致病作用。基于这些发现，我们假设miR-29b-1-5p/miR-29b-1-3p的比率随着年龄的增长而增加，从而倾向于抗稳定性特征。我们进一步假设miR-29b-1-5p（抗miRNA疗法）的抑制剂将有效逆转抗肌生成作用并随着年龄的发展促进骨骼再生。在此提案中，我们旨在阐明miR-29b-1-5p抑制成骨基因靶标并破坏MSC随老化的成骨分化的成骨分化，并确定MIR-29B-1-5P水平对MSC介导的局部骨形成的影响，并确定使用新型polymerelgel使用新型polymerelgels的局部骨形成的影响。为了解决这些目标，我们将在采用已建立的原位骨损伤模型之前使用各种分子细胞生物学和功能测定法。这些研究将为miR-29b-1-5p抑制剂的治疗潜力提供临床前证据，以促进骨骼再生以及有效且改进的抗MIRNA治疗系统。