Renal repair effects of senolytic preconditioned mesenchymal stromal cells in diabetic kidney disease

摘要/项目总结 糖尿病肾病（DKD）是全球肾脏疾病负担的主要驱动因素， 治疗方案。因此，开发有效的治疗方法来减缓DKD的进展至关重要。 间充质基质细胞（MSC），被批准用于治疗难治性炎症性疾病，具有 旁分泌抗纤维化、抗凋亡、促血管生成和免疫调节再生活性， 为DKD带来希望来自我们的I期临床试验的中期分析， 糖尿病性肾血管疾病证明了安全性，保留了肾功能，改善了肾血 流在实验性DKD中，MSC减少肾小球硬化、微量白蛋白尿、炎症和纤维化。 我们希望测试患者来源的MSC治疗的潜力，以最大限度地减少同种异体致敏或细胞毒性的风险。 同种异体干细胞治疗方法的破坏。然而，来自DKD个体的MSC可能 由于衰老而功能不佳。细胞衰老是细胞增殖的不可逆停滞， 由DNA损伤诱导并促进炎症，导致组织损伤和细胞功能障碍。在我们 I期随机开放标签试验，我们目前正在测试senolytics的安全性和有效性， 清除衰老细胞，修复DKD个体MSC的健康。初步研究显示， 在衰老的脂肪细胞和改善MSC功能。然而，目前尚不清楚这些变化是否 影响MSC对受损肾细胞或DKD的修复能力。我们的长远目标是促进 开发一种新的基于细胞的DKD疗法。我们假设受试者服用的衰老清除剂 与DKD的联合治疗将通过增强抗- 炎性、抗纤维化和促血管生成旁分泌活性。使用脂肪来源的MSC 从正在进行衰老清除治疗的晚期DKD（eGFR 15-45 ml/min/1.73 m2）受试者中采集 试验，拟议的项目将：（1）测试的假设，DKD骨髓间充质干细胞从受试者在体内治疗， Senolytics（SenDKD-MSC）将实现炎症和上皮间质细胞的更大减少， 在体外损伤的肾小管上皮细胞（TEC）中通过旁分泌介导的作用， 与未处理的DKD-MSC相比。(2)检验SenDKD-MSC输注将表现出更大的 与DKD-MSC相比，通过减少白蛋白尿、纤维化、缺氧， 血管紧张素II诱导的高血压实验性DKD中的炎症这些试点研究将使 在实验性DKD中评估senolytic-induced MSC肾修复作用，并增强成功的 在人DKD中测试新的衰老清除MSC预处理策略。意义和影响：基于细胞 延迟DKD进展的治疗是非常有希望的。衰老清除疗法可以改善干细胞功能， 多种与衰老有关的疾病揭示这些新的干预措施可能发挥作用的机制， 协同再生糖尿病肾脏可能会导致未来成功的大规模临床试验。

ABSTRACT / PROJECT SUMMARY Diabetic kidney disease (DKD), the leading driver of the global burden of kidney disease, is resistant to most treatment options. Thus, development of effective therapies to slow the progression of DKD is crucial. Mesenchymal stromal cells (MSC), approved for treating refractory inflammatory diseases elsewhere, possess paracrine anti-fibrotic, anti-apoptotic, pro-angiogenic and immunomodulatory regenerative activities, offering hope for DKD. Interim analyses from our Phase I clinical trial delivering patient-derived MSC in non- diabetic renovascular disease demonstrated safety, preserved kidney function, and improved kidney blood flow. In experimental DKD, MSC decrease glomerulosclerosis, microalbuminuria, inflammation and fibrosis. We wish to test the potential of patient-derived MSC therapy to minimize the risk of allosensitization or cell destruction with allogeneic stem cell treatment approaches. However, MSC from individuals with DKD may function suboptimally due to senescence. Cellular senescence, an irreversible arrest of cell proliferation, is induced by DNA damage and promotes inflammation, contributing to tissue injury and cell dysfunction. In our Phase I randomized, open label trial, we are currently testing the safety and efficacy of senolytics, drugs that clear senescent cells, to repair the health of MSC in individuals with DKD. Preliminary studies show reductions in senescent adipose cells and improved MSC function. However, it remains unclear whether these changes affect MSC reparative capacity on injured renal cells or in DKD. Our long-term goal is to promote the development of a novel cell-based therapy for DKD. We hypothesize that senolytic agents taken by subjects with DKD will improve the renal repair capacity of the patient’s own MSC, by enhancing anti- inflammatory, anti-fibrotic and pro-angiogenic paracrine activities. Using adipose-derived MSCs harvested from subjects with advanced DKD (eGFR 15-45 ml/min/1.73m2) in the ongoing senolytic therapy trial, the proposed project will: (1) Test the hypothesis that DKD MSCs from subjects treated in vivo with senolytics (SenDKD-MSC) will achieve greater reduction in inflammation and epithelial-to-mesenchymal transition (EMT) program in injured renal tubule epithelial cells (TEC) in vitro, via paracrine-mediated actions, as compared to untreated DKD-MSC. (2) Test the hypothesis that SenDKD-MSC infusion will exhibit greater potency vs. DKD-MSC in the repair of mouse kidneys in vivo, by reducing albuminuria, fibrosis, hypoxia, and inflammation in experimental DKD with angiotensin II-induced hypertension. These pilot studies will allow the assessment of senolytic-induced MSC renal repair effects in experimental DKD and enhance successful testing of a novel, senolytic MSC preconditioning strategy in human DKD. Significance and Impact: Cell-based therapy to delay DKD progression is very promising. Senolytic therapy may improve stem cell function and multiple aging-related conditions. Unravelling the mechanisms by which these novel interventions may work to synergistically regenerate the diabetic kidney could lead to successful large-scale clinical trials in the future.