CCL20 Is Increased in Hypercholesterolemic Subjects and Is Upregulated By LDL in Vascular Smooth Muscle Cells

Abstract

Objective-Our aim was to analyze the regulation of CC Chemokine ligand 20 (CCL20) by LDL in human vascular smooth muscle cells (VSMC). Methods and Results-In asymptomatic subjects, circulating CCL20 levels were higher in patients with hypercholesterolemia (18.5Ϯ3.2 versus 9.1Ϯ1.3 pg/mL; PϽ0.01). LDL induced the expression of CCL20 in VSMC in a dose-and time-dependent manner. Increased levels of CCL20 secreted by LDL-treated VSMC significantly induced human lymphocyte migration, an effect reduced by CCL20 silencing. The upregulation of CCL20 by LDL was dependent on the activation of kinase signaling pathways and NF-B. By site-directed mutagenesis, electrophoretic mobility shift assay, and chromatin immunoprecipitation, we identified a NF-B site (Ϫ80/Ϫ71) in CCL20 promoter critical for LDL responsiveness. Lysophosphatidic acid mimicked the upregulation of CCL20 induced by LDL, and minimal oxidation of LDL increased the ability of LDL to induce CCL20 through a mechanism that involves lysophosphatidic acid receptors. CCL20 was overexpressed in atherosclerotic lesions from coronary artery patients, colocalizing with VSMC. CCL20 was detected in conditioned media from healthy human aorta and its levels were significantly higher in secretomes from carotid endarterectomy specimens. A therosclerosis is essentially an inflammatory chronic disease. [1][2][3] Inflammation is a necessary response to injury and infection. Virtually all cardiovascular risk factors are capable of promoting an inflammatory response; among them, however, elevated levels of plasma cholesterol, in particular LDL, are recognized as one of the most important risk factors for atherosclerosis. 4,5 The inflammatory response involves the coordinated regulation of cell adhesion and migration and the establishment of a chemotactic gradient that guides inflammatory cells to damaged tissues. Key elements in this communication network are cytokines and chemokines, which orchestrate the recruitment, survival, expansion, and effector function of inflammatory cells. 6 -8 Chemokines are a superfamily of structurally related small chemotactic cytokines that control leukocyte function through interactions with their cognate 7-transmembranedomain G protein-coupled receptors. Monocytes/macrophages and T lymphocytes are the most abundant inflammatory cells found in atherosclerotic plaques, 9,10 but also B cells, dendritic cells, and neutrophils contribute to the pathogenesis of atherosclerosis. 9,11,12 Native and modified LDL modulate the expression of key genes involved in the recruitment and trafficking of inflammatory cells including cellular adhesion molecules and chemokines such as monocyte chemotactic protein 1. 4,5,[13][14][15] Recent studies have implicated other chemokines in atherosclerosis and have extended the knowledge about the regulation of chemokines/chemokine receptors on vascular cells, 6 -8 but the complete picture of these molecules involved in atherogenesis is not completely understood. Conclusion-ThisIncreasing data involving innate and adapti...

Mutations in BALB mitochondrial DNA induce CCL20 up-regulation promoting tumorigenic phenotypes

“…We demonstrate here, that inhibitors of NF-κB activation (BAY11-7082) and MAPK signaling (PD98059) were able to significantly decrease CCL20/CCR6 expression levels in mtBALB cybrids suggesting that expression of CCL20/CCR6 can be partially regulated by inhibition of NF-κB and/or MAPK signaling. This is in correlation with Calvayrac et al (39) and with Wang et al (40) who prevented the up-regulation of CCL20 by inhibiting of NF-κB. Additionally, it was indicated that NF-κB is involved in modulation of CCL20 by other mediators such as TNFα in some human cancer cells (41), prolactin in keratinocytes (42) or hypoxia in primary human monocytes (43).…”

“…Fleming et al also demonstrated that chemokine CCL20 can enhance migratory capabilities of cutaneous keratinocytes (37) through up-regulating of CCL20 by inflammation (38). Moreover, Calvayrac et al (39) showed that increased release of CCL20 significantly induced human lymphocyte migration in transwell assay. Thus, we assumed that increased migration of mtBALB cybrids might be caused by higher expression of CCL20 in these cells.…”

Interleukin-1β modulates smooth muscle cell phenotype to a distinct inflammatory state relative to PDGF-DD via NF-κB-dependent mechanisms

“…Additionally, studies of NF-B inhibition in SMCs revealed that NF-B plays an important role in mediating IL-1␤-dependent induction of several of these genes. Although previous studies have demonstrated that NF-B mediates induction of several proinflammatory genes in SMCs including VCAM-1 and CCL20 (9,32), our unbiased analysis of transcription factor binding sites combined with NF-B inhibition studies in cultured SMCs provides novel evidence that NF-B is a major regulator of the marked and distinct inflammatory gene expression by IL-1. In addition, results reported here demonstrate novel roles for NF-B in promoting expression of proinflammatory genes such as P-selectin in SMCs.…”

Regulation of Atherogenesis by Chemokines and Chemokine Receptors

“…Both CCR6 and its sole chemokine ligand CCL20 (also known as M acrophage I nflammatory P rotein [MIP] 3 α) are expressed at increased levels in human atherosclerotic plaques, and the circulating level of CCL20 is significantly increased in hypercholesterolemic subjects (Calvayrac et al 2011; Yilmaz et al 2007). In mice, Ccr6 and Ccl20 are both present constitutively in healthy aortas and in atherosclerotic plaques, and Ccr6 deletion in ApoE −/− mice fed a Western diet significantly reduced the atherosclerotic lesion size in both the whole aorta and the aortic root, accompanied by a reduction of macrophage content in the plaques (Wan et al 2011a).…”