Objective: This study aims to explore whether homeobox A11 antisense RNA (HOXA11-AS) could regulate inflammation induced by diabetic arteriosclerosis (DAA) via PI3K/AKT pathway.
Patients and methods: Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was used to detect expressions of HOXA11-AS and proinflammatory genes in carotid endarterectomy samples of symptomatic and asymptomatic atherosclerosis (AS) patients, diabetes mellitus (DM), and non-DM patients. The above-mentioned genes in DM animal model and non-DM animal model were also detected. We detected the expression of HOXA11-AS in vascular smooth muscle cells (VSMCs) treated with platelet-derived growth factor (PDGF) or PDGF inhibitor imatinib, respectively. Subsequently, we applied cell transfection technology to interfere with the expression of HOXA11-AS in VSMCs. In vascular endothelial cells (VECs) and VSMCs, we detected the effect of HOXA11-AS on the expressions of genes related to the proliferation, migration, and cell cycle. Then, VSMCs were treated with tumor necrosis factor-α (TNF-α), and the expression of HOXA11-AS was examined in VSMCs. The effect of HOXA11-AS on TNF-α-induced inflammation in VSMCs was detected as well. Finally, we analyzed the effect of HOXA11-AS on PDGF-induced activation of PI3K/AKT pathway in VSMCs and VECs.
Results: HOXA11-AS expression was markedly increased in carotid endarterectomy specimens of symptomatic AS patients compared to that of asymptomatic AS patients. Expression levels of HOXA11-AS and pro-inflammatory genes were significantly elevated in carotid endarterectomy specimens of DM patients. Similarly, HOXA11-AS expression was also significantly increased in carotid arteries of DM mice compared with that of non-DM mice. PDGF could upregulate HOXA11-AS expression in VSMCs, which was reversed by PDGF inhibitor imatinib. HOXA11-AS knockdown could reduce the expressions of the proliferation-associated gene (PCNA) and the cycle-related genes (p21, p53), and also inhibited the proliferation and migration of VSMCs induced by PDGF. HOXA11-AS was upregulated by TNF-α. HOXA11-AS knockdown remarkably downregulated expressions of inflammation-related genes in VSMCs induced by TNF-α. In VECs, low expression of HOXA11-AS can inhibit the expression of TNF-α-induced pro-inflammatory genes and PDGF-induced vascular inflammation-related genes. Low expression of HOXA11-AS inhibited PDGF-induced activation of PI3K/AKT pathway in VSMCs and VECs.
Conclusions: HOXA11-AS may participate in DAA by activating the PI3K/AKT pathway to regulate inflammation in VSMCs and VECs.