活性成纤维细胞外泌体来源的miR-133/143通过调控Rab9促进自噬在BPH发病中的机制研究

Benign prostatic hyperplasia (BPH) is a common disease in middle-aged and elderly men. Its pathogenesis is closely related to inflammation, however, the regulatory mechanisms between them are not clear. Our previous studies found that a large number of inflammatory related macrophages infiltrate in BPH stromal compartment, which is able to promote prostate stromal fibroblasts growth and activation through paracrine TGF-β1. Moreover, the expression level of exosomal miRNA-133/143 upregulated significantly after the activation of fibroblast. Bioinformatics and RNA-seq confirmed that Rab9 is a target of miRNA-133/143. In addition, we also proved that increase of ATG9A level in fibroblasts promotes BPH progression through inducing autophagy. Accordingly, we believe that exosomal miRNA-133/143, that released by macrophage induced activated stromal fibroblasts, can be transmited into surrounding normal fibroblasts. This process increases ATG9A activity as well as autophagy in stromal fibroblasts via regulating Rab9, which further promotes the development of BPH. Through this project, we intends to clarify the function of inflammation and fibroblasts in the pathogenesis of BPH by using different experimental methods. More importantly, we hope the establishment of the macrophage-fibroblast-exosomes-autophagy regulatory network will help to clarify the autophagy-inducing mechanism of activated fibroblasts derived exosomal miRNAs and provide new strategies for management of BPH.

良性前列腺增生（BPH）的发病与炎症关系密切，但两者之间的调控机制尚不明确。课题组前期研究发现炎症相关巨噬细胞在BPH基质中大量浸润，通过旁分泌TGF-β1促进前列腺基质成纤维细胞活化，而活化的成纤维细胞外泌体中miR-133/143表达发生了明显上调，利用生物信息学分析和RNA测序证实Rab9是其靶基因；同时在成纤维细胞中发现自噬相关蛋白9A（ATG9A）在BPH进展中起到关键的作用。据此我们认为：巨噬细胞诱导的活性成纤维细胞释放外泌体，将miR-133/143转运至周围正常成纤维细胞，通过干扰Rab9进而调控ATG9A活性，促进细胞自噬，导致BPH的发生发展。本项目通过分子、细胞及组织等不同层面的实验手段，深入研究“巨噬细胞-成纤维细胞-外泌体-自噬”调控网络，明确活性成纤维细胞外泌体来源的miRNA促进自噬在BPH发病中作用和机制，为BPH的防治提供新的思路。

当前，良性前列腺增生（BPH）的发病与炎症关系密切，但两者之间的调控机制尚不明确。本研究发现，炎症相关巨噬细胞在BPH基质中大量浸润，并通过旁分泌TGF-β1促进前列腺基质成纤维细胞活化，而活化后的前列腺基质成纤维细胞外泌体中miR-7-5p表达发生了上调，使得微环境中正常前列腺基质成纤维细胞中miR-7-5p水平上升，抑制了细胞内DDIT4的表达，诱导细胞自噬并促进基质成纤维细胞增殖。另外，我们还发现了PDE5抑制剂基于抑制前列腺基质成纤维细胞活化的新机制，即PDE5抑制剂通过促进miR-3126-3p的表达，抑制活化的前列腺基质成纤维细胞中FGF9的表达和分泌，进而抑制BPH的发生发展。本研究明确了炎症相关巨噬细胞对前列腺基质成纤维细胞活化的影响，发现了活化后的前列腺基质成纤维细胞通过外泌体途径对正常基质细胞的作用，并探索了PDE5抑制剂在BPH治疗中的新机制，为BPH的临床治疗提供前期实验基础。