G-Protein-Coupled Receptor 35 Mediates Human Saphenous Vein Vascular Smooth Muscle Cell Migration and Endothelial Cell Proliferation

Abstract

Vascular smooth muscle cell (VSMC) migration and proliferation is central to neointima formation in vein graft failure following coronary artery bypass. However, there are currently no pharmacological interventions that prevent vein graft failure through intimal occlusion. It is hence a therapeutic target. Here, we investigated the contribution of GPR35 to human VSMC and endothelial cell (EC) migration, using a scratch-wound assay, and also the contribution to proliferation, using MTS and BrdU assays, in in vitro models using recently characterized human GPR35 ortholog-selective small-molecule agonists and antagonists. Real-time PCR studies showed GPR35 to be robustly expressed in human VSMCs and ECs. Stimulation of GPR35, with either the human-selective agonist pamoic acid or the reference agonist zaprinast, promoted VSMC migration in the scratch-wound assay. These effects were blocked by coincubation with either of the human GPR35-specific antagonists, CID-2745687 or ML-145. These GPR35-mediated effects were produced by inducing alterations in the actin cytoskeleton via the Rho A/Rho kinase signaling axis. Additionally, the agonist ligands stimulated a proliferative response in ECs. These studies highlight the potential that small molecules that stimulate or block GPR35 activity can modulate vascular proliferation and migration. These data propose GPR35 as a translational therapeutic target in vascular remodeling.

G protein‐coupled receptors not currently in the spotlight: free fatty acid receptor 2 and GPR35

“…(), assuming that CID‐2745687 was actually acting via GPR35 in these studies. However, in a more positive context, in isolated human saphenous vein smooth muscle cells, GPR35 agonist‐induced cell lengthening and cell migration were both blocked effectively by concentrations of both CID‐2745687 and ML‐145 consistent with reports on the affinity of these ligands at human GPR35, as defined from in vitro studies (McCallum et al, ), as was proliferation of human saphenous vein endothelial cells (McCallum et al, ).…”

“…This has been assessed in experiments measuring agonist‐induced binding of [ 35 S]GTP[S] to an introduced epitope‐tagged form of Gα 13 (Jenkins et al, ) and in assays employing a chimeric Gα q /Gα 13 G protein that allows receptor interaction with Gα 13 to be converted into elevation of intracellular Ca 2+ levels (Jenkins et al, ). Moreover, in human saphenous vein smooth muscle cells, GPR35 agonist‐induced cell migration is inhibited by each of two mechanistically distinct Rho‐kinase inhibitors (McCallum et al, ). Although activation of Gα 13 does not directly regulate levels of secondary messengers, it does regulate Rho‐guanine nucleotide exchange factors.…”

Overexpression of GPR35 confers drug resistance in NSCLC cells by β-arrestin/Akt signaling

“… 15 Functionally, it is demonstrated that GPR35 mediates smooth muscle cell migration and endothelial cell proliferation. 16 GPR35 also induces hypoxia-inducible factor-1 alpha to regulate cellular processes. 17 Besides, GPR35 is identified as a susceptibility gene associated with chronic anthracycline-induced cardio-toxicity in pediatric cancer patients.…”

Inhibition of miR-155 attenuates abdominal aortic aneurysm in mice by regulating macrophage-mediated inflammation

“…Research have shown that phenotypic transition of VSMC drives the progression of vascular diseases, such as atherosclerosis, diabetes, restenosis, and hypertension [ 11 ]. VSMCs are associated with vessel injury and remodeling in the proinflammatory environment [ 12 , 13 ]. In the normal vessel wall, VSMCs are static, differentiated, contractile and have low rate of proliferation, and express high levels of contractile proteins such as α-smooth muscle actin (α-SMA) [ 14 ].…”