Connexin 43 is differentially distributed within renal vasculature and mediates profibrotic differentiation in medullary fibroblasts.

Connexin 43 is differentially distributed within renal vasculature and mediates profibrotic differentiation in medullary fibroblasts. Am J Physiol Renal Physiol. 2020 Nov 16;: Authors: Xu Y, Hu J, Yilmaz DE, Bachmann S Abstract Connexins (Cxs) form gap junctions for intercellular exchange of inorganic ions and messenger molecules. In the kidney, Cxs play essential roles within its compartments, but data on the precise cellular localization and cell type-related function of their isoforms are scarce. We have tested whether Cx43 distribution is restricted to vascular and interstitial cells and whether medullary fibroblasts express Cx43 to coordinate profibrotic signaling. Confocal immunofluorescence techniques, ultrastructural labeling, and functional studies in cell culture were performed. Cx43 was chiefly expressed in the vasculature, but absent from tubular epithelia. All arterial, arteriolar and lymphatic endothelia showed continous Cx43 signal along their borders. In the inner medulla, only the interstitium showed Cx43 signals which were assigned to fibroblasts and their processes. Cultured, Cx43-expressing medullary fibroblasts served to study the role of gap junctions in a profibrotic context. Using a dye spreading assay, Cx43-sensitive diffusion of Lucifer Yellow was dependent on gap junctional passage. Adding transforming growth factor-β1 (5 ng/ml for 48 h) activated Cx43 biosynthesis and caused Cx43-sensitive transformation ...
Source: American Journal of Physiology. Renal Physiology - Category: Physiology Authors: Tags: Am J Physiol Renal Physiol Source Type: research