Bone Marrow Neuropathy Drives Diabetic Retinopathy

描述（由申请人提供）：在上一个资助期，我们证明了糖尿病个体和小鼠表现出功能障碍的内皮祖细胞。这些骨髓（BM）衍生的细胞由于糖尿病诱导的BM神经病变而以异常方式释放到循环中。这种BM神经病变导致这些细胞进入循环的昼夜节律释放失调。这些BM变化先于糖尿病视网膜病变（DR）的发展，首次将BM神经病变与DR联系起来。糖尿病BM上清液（而非对照）含有高水平的单核细胞/巨噬细胞集落刺激因子（M-CSF），并且糖尿病小鼠在视网膜和循环中表现出单核细胞数量的增加。基于这些发现，我们假设：糖尿病BM去神经支配引发HSC/祖细胞功能障碍，导致产生的总单核细胞增加，这与视网膜神经胶质细胞CCL 2（单核细胞趋化蛋白-1）表达增加相结合，导致糖尿病视网膜中促炎（M1）单核细胞水平过高。此外，功能失调的神经元CX 3CL 1（fractalkine）表达水平降低，加剧了常驻小胶质细胞的炎症反应。这种不平衡导致神经炎症，加速DR发病机制。我们将通过同时探索以下目标在体外和体内检验这一假设：目标1：为了确定糖尿病诱导的BM神经病变是否是BM基质细胞产生M-CSF增加的原因，所述BM基质细胞使造血转向产生过量的单核细胞，特别是促炎性Gr 1 +/CCR 2 +/CX 3CR 110单核细胞，而不是保护性的Gr 1-/CCR 2-/CX 3CR 1hi单核细胞。目标二：确定CCL 2和CX 3CL 1在DR炎症中的作用，并测试CCR 2 + CX 3CR 1 lo和CCR 2-/CX 3CR 1hi单核细胞平衡的恢复以及视网膜血管内皮祖细胞水平的同时恢复是否会预防或逆转T1 D小鼠的DR。目标3：我们的假设预测循环促炎性Gr 1 +/CCR 2 +i/CX 3CR 1 lo细胞将引起内皮细胞活化，促进白细胞停滞并导致视网膜通透性增强，而Gr 1-/CCR 2-/CX 3CR 1hi细胞将保护糖尿病中的BRB。我们将研究操纵这些亚群对DR进展的影响。靶向单核细胞亚型可能是DR预防和治疗的理想策略。CellMax？

DESCRIPTION (provided by applicant): In the previous funding period, we demonstrated that diabetic individuals and mice demonstrate dysfunctional endothelial progenitor cells. These bone marrow (BM) derived cells are released into the circulation in an abnormal manner due to diabetes-induced BM neuropathy. This BM neuropathy leads to dysregulation in the circadian release of these cells into the circulation. These BM changes precede development of diabetic retinopathy (DR) linking BM neuropathy for the first time to DR. Diabetic BM supernatants, but not control, contain high levels of monocyte/macrophage-colony stimulating factor (M-CSF) and diabetic mice exhibit an increase number of monocytes in the retina and circulation. Based on these findings, we hypothesize that: Diabetic BM denervation initiates HSC/progenitor dysfunction that leads to an increase in total monocytes generated, this, coupled with increased expression of CCL2 (monocyte chemoattractent protein-1) by retinal glia results in excessive levels of the pro-inflammatory (M1) monocytes in the diabetic retina. In addition, diminished levels of CX3CL1 (fractalkine) expression by dysfunctional neurons heightens the inflammatory response of resident microglia. This imbalance leads to a neural inflammation that accelerates DR pathogenesis. We will test this hypothesis both in vitro and in vivo through the simultaneous exploration of the following aims: Aim 1: To determine whether diabetes induced BM neuropathy is responsible for increased M-CSF production by BM stromal cells which shifts hematopoiesis towards generation of excessive numbers of monocytes, in particular pro-inflammatory Gr1+/CCR2+/CX3CR1lo monocytes, rather than the protective Gr1-/CCR2-/CX3CR1hi monocytes. Aim 2: To determine the roles of CCL2 and CX3CL1 in DR inflammation and to test whether restoration of the balance of CCR2+CX3CR1lo and CCR2-/CX3CR1hi monocytes and simultaneous restoration of levels of endothelial progenitors to retinal vasculature will prevent o reverse DR in T1D mice. Aim 3: Our hypothesis predicts that circulating pro- inflammatory Gr1+/CCR2+i/CX3CR1lo cells will cause endothelial cell activation, promote leukostasis and result in enhanced retinal permeability whereas Gr1-/CCR2-/CX3CR1hi cells will protect the BRB in diabetes. We will examine the effects of manipulating these subsets on the progression of DR. Targeting monocyte subtypes may represent an ideal strategy for DR prevention and treatment. CellMax?