Compound C Inhibits Vascular Smooth Muscle Cell Proliferation and Migration in an AMP-Activated Protein Kinase-Independent Fashion

Abstract

6-[4-(2-Piperidin-1-yl-ethoxy)-phenyl]-3-pyridin-4-yl-pyrazolo [1,5-a] pyrimidine (compound C) is a cell-permeable pyrrazolopyrimidine derivative that acts as a potent inhibitor of AMPactivated protein kinase (AMPK). Although compound C is often used to determine the role of AMPK in various physiological processes, it also evokes AMPK-independent actions. In the present study, we investigated whether compound C influences vascular smooth muscle cell (SMC) function through the AMPK pathway. Treatment of rat aortic SMCs with compound C (0.02-10 M) inhibited vascular SMC proliferation and migration in a concentration-dependent fashion. These actions of compound C were not mimicked or affected by silencing AMPK␣ expression or infecting SMCs with an adenovirus expressing a dominant-negative mutant of AMPK. In contrast, the pharmacological activator of AMPK 5-aminoimidazole-4-carboxamide-1-␤-D-ribofuranoside inhibited the proliferation and migration of SMCs in a manner that was strictly dependent on AMPK activity. Flow cytometry experiments revealed that compound C arrested SMCs in the G 0 /G 1 phase of the cell cycle, and this was associated with a decrease in cyclin D1 and cyclin A protein expression and retinoblastoma protein phosphorylation and an increase in p21 protein expression. Finally, local perivascular delivery of compound C immediately after balloon injury of rat carotid arteries markedly attenuated neointima formation. These studies identify compound C as a novel AMPKindependent regulator of vascular SMC function that exerts inhibitory effects on SMC proliferation and migration and neointima formation after arterial injury. Compound C represents a potentially new therapeutic agent in treating and preventing occlusive vascular disease.

Pioglitazone Attenuates Injury-Induced Neointima Formation in Mouse Femoral Artery Partially through the Activation of AMP-Activated Protein Kinase

“…Of importance, compound C counters the inhibition of neointima formation by PIO (present study), an adipokine (e.g., omentin) [33], and a calcium channel blocker (e.g., nifedipine) [48]. Although these findings with compound C suggest a potential role for activated AMPK to inhibit neointima formation, compound C has also been shown to exhibit AMPK-independent effects [49]. While perivascular delivery of compound C attenuates neointima formation in balloon-injured rat carotid artery via AMPK-independent mechanism [49], intra-peritoneal administration of compound C tends to increase neointima formation in guidewire-injured mouse femoral artery (Uemura et al [33]; and present study).…”

“…Although these findings with compound C suggest a potential role for activated AMPK to inhibit neointima formation, compound C has also been shown to exhibit AMPK-independent effects [49]. While perivascular delivery of compound C attenuates neointima formation in balloon-injured rat carotid artery via AMPK-independent mechanism [49], intra-peritoneal administration of compound C tends to increase neointima formation in guidewire-injured mouse femoral artery (Uemura et al [33]; and present study). Since compound C treatment alone tends to increase neo-intima formation likely through proliferative signaling pathways independent of AMPK, this may also play a role in countering PIO-mediated inhibition of neointima formation.…”

Simvastatin alleviated diabetes mellitus‐induced erectile dysfunction in rats by enhancing AMPK pathway‐induced autophagy

“…CMSCs were purified by double adherence to plastic culture plates with different time conditions. After 2‐3 passages, the cells (cell number was 4.90 × 10 5 /per petri dish, and viability was 4.62 × 10 5 (94.29%)/per petri dish) were treated with the following drugs for 24 hours: control group (0.1% DMSO), DMED group (0.1% DMSO), DMED + sim group (simvastatin, 2 μM), and DMED + sim + compound C group (simvastatin, 2 μM, and compound C, 2 μM) . The curve of relative cell viability and dose are provided in the Supplemental Information (SI).…”

Identification of novel peptide motifs in the serpin maspin that affect vascular smooth muscle cell function

“…We investigated the effect of maspin peptides on the activation state of signalling molecules AMPK and ERK1/2, which are known to be involved in cell migration [22,23]. Using cell-based ELISA we looked at the effect of maspin peptides S4B and S5B on ERK1/2 phosphorylation ( Figure 5A) and the effect of the long peptide ( Figure 5B).…”

“…AMPK has been previously shown to decrease migration of VSMC [23,24]. To test whether the decrease in migration mediated by maspin peptides required AMPK, VSMC were treated with the AMPK inhibitor dorsomorphrin and migration in response to the long peptide was determined.…”