c-Kit modifies the inflammatory status of smooth muscle cells

• Published in: PeerJ (San Francisco, CA) Vol. 5; p. e3418
• Main Authors: Song, Lei, Martinez, Laisel, Zigmond, Zachary M, Hernandez, Diana R, Lassance-Soares, Roberta M, Selman, Guillermo, Vazquez-Padron, Roberto I
• Format: Journal Article
• Language: English
• Published: United States PeerJ. Ltd 13.06.2017; PeerJ, Inc; PeerJ Inc
• Subjects: Analysis; c-Kit; c-Kit protein; Cardiology; Cell cycle; DNA microarrays; Gene expression; Genetic transformation; Hypertension; Inflammation; Kinases; Methods; Molecular Biology; NF-κB; NF-κB protein; Pharmacology; Phospholipids; Physiological aspects; Polymerase chain reaction; POVPC; Protein-tyrosine kinase receptors; Pulmonary arteries; Rodents; Smooth muscle; Smooth muscle cell; Stem cells; Surgery; TAK1; TAK1 protein; Transcription; Transforming growth factors; Veins & arteries; Smooth muscle cell; NF-κB; TAK1; c-Kit; POVPC; Inflammation; NLK
• ISSN: 2167-8359; 2167-8359
• DOI: 10.7717/peerj.3418

c-Kit is a receptor tyrosine kinase present in multiple cell types, including vascular smooth muscle cells (SMC). However, little is known about how c-Kit influences SMC biology and vascular pathogenesis. High-throughput microarray assays and pathway analysis were used to identify differentially expressed genes between primary c-Kit deficient (Kit ) and control (Kit ) SMC. Quantitative real-time RT-PCR and functional assays further confirmed the differences in gene expression and pro-inflammatory pathway regulation between both SMC populations. The microarray analysis revealed elevated NF-κB gene expression secondary to the loss of c-Kit that affects both the canonical and alternative NF-κB pathways. Upon stimulation with an oxidized phospholipid as pro-inflammatory agent, c-Kit deficient SMC displayed enhanced NF-κB transcriptional activity, higher phosphorylated/total p65 ratio, and increased protein expression of NF-κB regulated pro-inflammatory mediators with respect to cells from control mice. The pro-inflammatory phenotype of mutant cells was ameliorated after restoring c-Kit activity using lentiviral transduction. Functional assays further demonstrated that c-Kit suppresses NF-κB activity in SMC in a TGFβ-activated kinase 1 (TAK1) and Nemo-like kinase (NLK) dependent manner. Our study suggests a novel mechanism by which c-Kit suppresses NF-κB regulated pathways in SMC to prevent their pro-inflammatory transformation.