Most lesions that decrease renal blood flow originate within the renal artery; however; large, aortic, atherosclerotic plaques can overhang the renal ostium producing a functional renal artery ...stenosis. At the Hospital of the University of Pennsylvania, 45 consecutive percutaneous transluminal angioplasties were examined retrospectively and classified as to site of the obstructing lesions and clinical outcome. Stenoses within the renal artery responded very well to angioplasty, with 83% of patients showing either an excellent or good result. Conversely, when aortic plaques were responsible for inflow obstruction, 76% of patients responded poorly or not at all to balloon dilatation. It is proposed that this disparity of response reflects the anatomic differences in the orientation of elastic and collagen fibers of the muscularis and advential layers of the renal artery and the aorta.
While the peripheral nervous system has regenerative ability, restoration of sufficient function remains a challenge. Vimentin has been shown to be localized in axonal growth fronts and associated ...with nerve regeneration, including myelination, neuroplasticity, kinase signaling in nerve axoplasm, and cell migration; however, the mechanisms regulating its expression within Schwann cell (SC) remain unexplored. The aim of this study was to profile the spatial and temporal expression profile of microRNA (miRNA) in a regenerating rat sciatic nerve after transection, and explore the potential role of miR-138-5p targeting vimentin in SC proliferation and migration. A rat sciatic nerve transection model, utilizing a polyethylene nerve guide, was used to investigate miRNA expression at 7, 14, 30, 60, and 90 days during nerve regeneration. Relative levels of miRNA expression were determined using microarray analysis and subsequently validated with quantitative real-time polymerase chain reaction. In vitro assays were conducted with cultured Schwann cells transfected with miRNA mimics and assessed for migratory and proliferative potential. The top seven dysregulated miRNAs reported in this study have been implicated in cell migration elsewhere, and GO and KEGG analyses predicted activities essential to wound healing. Transfection of one of these, miRNA-138-5p, into SCs reduced cell migration and proliferation. miR-138-5p has been shown to directly target vimentin in cancer cells, and the luciferase assay performed here in rat Schwann cells confirmed it. These results detail a role of miR-138-5p in rat peripheral nerve regeneration and expand on reports of it as an important regulator in the peripheral nervous system.
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