陈小三
阜外华中心血管病医院 血管外科
OBJECTIVES:Recent studies validated the expression of extraoral bitter taste receptors and established the importance of regulatory functions that are associated with various cellular biological processes of these receptors. However, the importance of bitter taste receptors' activity in neointimal hyperplasia has not yet been recognized. The bitter taste receptors activator amarogentin (AMA) is known to regulate a variety of cellular signals, including AMP-activated protein kinase (AMPK), STAT3, Akt, ERK, and p53, which are associated with neointimal hyperplasia.MATERIALS AND METHODS:The present study assessed the effects of AMA on neointimal hyperplasia and explored the potential underlying mechanisms.RESULTS:No cytotoxic concentration of AMA significantly inhibited the proliferation and migration of VSMCs induced by serum (15 % FBS) and PDGF-BB. In addition, AMA significantly inhibited neointimal hyperplasia of the cultured great saphenous vein in vitro and ligated mouse left carotid arteries in vivo, while the inhibitory effect of AMA on the proliferation and migration of VSMCs was mediated via the activation of AMPK-dependent signaling, which could be blocked via AMPK inhibition.CONCLUSION:The present study revealed that AMA inhibited the proliferation and migration of VSMCs and attenuated neointimal hyperplasia, both in ligated mice carotid artery and cultured saphenous vein, which was mediated via a mechanism that involved AMPK activation. Importantly, the study highlighted the potential of AMA to be explored as a new drug candidate for neointimal hyperplasia.
Biochimica et biophysica acta. Molecular basis of disease 2023
This study was designed to determine the effects of the long non-coding RNA (lncRNA) plasmacytoma variant translocation 1 (PVT1) on vascular smooth muscle cell (VSMC) apoptosis and extracellular matrix (ECM) disruption in a murine abdominal aortic aneurysm (AAA) model. After injection of PVT1-silencing lentiviruses, AAA was induced in Apolipoprotein E-deficient (ApoE-/-) male mice by angiotensin II (Ang II) infusion for four weeks. After Ang II infusion, mouse serum levels of pro-inflammatory cytokines were analysed, and aortic tissues were isolated for histological, RNA, and protein analysis. Our results also showed that PVT1 expression was significantly upregulated in abdominal aortic tissues from AAA patients compared with that in controls. Additionally, Ang II treatment significantly increased PVT1 expression, both in cultured mouse VSMCs and in AAA murine abdominal aortic tissues. Of note, the effects of Ang II in facilitating cell apoptosis, increasing matrix metalloproteinase (MMP)-2 and MMP-9, reducing tissue inhibitor of MMP (TIMP)-1, and promoting switching from the contractile to synthetic phenotype in cultured VSMCs were enhanced by overexpression of PVT1 but attenuated by knockdown of PVT1. Furthermore, knockdown of PVT1 reversed Ang II-induced AAA-associated alterations in mice, as evidenced by attenuation of aortic diameter dilation, marked adventitial thickening, loss of elastin in the aorta, enhanced aortic cell apoptosis, elevated MMP-2 and MMP-9, reduced TIMP-1, and increased pro-inflammatory cytokines. In conclusion, our findings demonstrate that knockdown of lncRNA PVT1 suppresses VSMC apoptosis, ECM disruption, and serum pro-inflammatory cytokines in a murine Ang II-induced AAA model.
Molecules and cells 2019
The aim of the present study was to identify abdominal aortic aneurysms (AAA)-associated miR-155 contributing to AAA pathology by regulating macrophage-mediated inflammation. Angiotensin II (AngII)-infused apolipoprotein E-deficient (ApoE-/-) mice and THP-1 cells model of miR-155 overexpression and deficiency were used in the experiments. The expression of miR-155 was detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Cytokines were evaluated using enzyme-linked immunoabsorbent assay (ELISA). Western blotting was used to measure the levels of MMP-2, MMP-9, iNOS, and monocyte chemoattractant protein (MCP)-1 proteins. Immunostaining and transwell were used to determine CD68, elastic collagen, proliferation, and migration of vascular smooth muscle cells (VSMCs). The results showed that miR-155 and cytokines were up-regulated in AAA patients or ApoE-/- mice. Overexpression of miR-155 enhanced MMP-2, MMP-9, iNOS, and MCP-1 levels, and stimulated the proliferation and migration of VSMCs. Meanwhile, inhibition of miR-155 had the opposite effect. In addition, histology demonstrated accumulation of CD68 and elastic collagen-positive areas significantly decreased in miR-155 antagomir injection group. In conclusion, the results of the present study suggest that inhibiting miR-155 is crucial to prevent the development of AAA by regulating macrophage inflammation.
Bioscience reports 2018