Renal nerves drive interstitial fibrogenesis in obstructive nephropathy

• Published in: Journal of the American Society of Nephrology 2013-02, Vol.24 (2), p.229-242
• Main Authors: Kim, Jinu, Padanilam, Babu J
• Format: Article
• Language: English
• Subjects: Animals; Apoptosis - physiology; Basic Research; Calcitonin Gene-Related Peptide - metabolism; Calcitonin Gene-Related Peptide - pharmacology; Caspases - metabolism; Denervation - methods; Fibrosis - metabolism; Fibrosis - pathology; Fibrosis - physiopathology; Kidney - drug effects; Kidney - innervation; Kidney - pathology; Male; Mice; Mice, 129 Strain; Necrosis; Nephritis - metabolism; Nephritis - pathology; Nephritis - physiopathology; Neurons, Afferent - metabolism; Neurons, Efferent - metabolism; Norepinephrine - metabolism; Norepinephrine - pharmacology; Receptors, Adrenergic, alpha-2 - metabolism; Renal Insufficiency, Chronic - metabolism; Renal Insufficiency, Chronic - pathology; Renal Insufficiency, Chronic - physiopathology; Signal Transduction - physiology; Ureteral Obstruction - metabolism; Ureteral Obstruction - pathology; Ureteral Obstruction - physiopathology; Vasoconstrictor Agents - metabolism; Vasoconstrictor Agents - pharmacology; Vasodilator Agents - metabolism; Vasodilator Agents - pharmacology
• ISSN: 1046-6673; 1533-3450
• DOI: 10.1681/ASN.2012070678

The signals that drive fibrogenesis after an initiating insult to the kidney are incompletely understood. Here, we report that renal nerve stimulation after ureteral obstruction is the primary profibrotic signal and that renal denervation prevents both fibrogenesis and the inflammatory cascade. Local infusion of neural factors, norepinephrine, and calcitonin gene-related peptide (CGRP) in denervated kidneys mimicked the fibrotic response observed in innervated obstructed kidneys. Norepinephrine and CGRP act through the α(2)-adrenergic receptor and CGRP receptor, respectively, because blocking these receptors prevented fibrosis, the inflammatory response, and tubular cell death. In tubular epithelial cells, both norepinephrine and CGRP induced apoptosis and the release of profibrotic factors capable of stimulating the differentiation of fibroblasts to myofibroblasts. In conclusion, these data suggest that nerve-derived signaling molecules may drive renal fibrosis and that their suppression may be a therapeutic approach to fibrosis prevention.