[Retracted] Rosuvastatin suppresses platelet­derived growth factor­BB­induced vascular smooth muscle cell proliferation and migration via the MAPK signaling pathway.

[This retracts the article DOI: 10.3892/etm.2013.1265.].

YTHDC2-Mediated circYTHDC2 N6-Methyladenosine Modification Promotes Vascular Smooth Muscle Cells Dysfunction Through Inhibiting Ten-Eleven Translocation 2.

Type 2 diabetes condition mediated vascular smooth muscle cell (VSMCs) dysfunction. However, the mechanism of VSMCs dysfunction in diabetic patients needs further elucidation. VSMCs are an important component of the vascular wall, participate in the process of vascular remodeling, and play a vital role in the vascular complications of diabetes. Studies have found that circular RNAs (circRNAs) play a key regulatory role in the occurrence and development of VSMCs dysfunction. In this study, we stimulated VSMCs with high glucose and identified a new circular RNA, circYTHDC2, using circRNA chip analysis. circYTHDC2 was highly expressed in VSMCs treated with high glucose. Knockout of circYTHDC2 significantly inhibited the proliferation and migration of VSMCs. Metformin treatment significantly inhibited the expression of YTHDC2 and circYTHDC2. The upstream mechanism analysis revealed that the stability of circYTHDC2 was regulated by YTHDC2-mediated m6A modification. Furthermore, circYTHDC2 negatively regulates the expression of Ten-Eleven Translocation 2 (TET2) by targeting the unstable motif of TET2 3'UTR, thereby promoting dedifferentiated "synthetic type" transformation of VSMC. Taken together, these results suggest that the YTHDC2/circYTHDC2/TET2 pathway is an important target of metformin in preventing the progression of VSMCs dysfunction under high glucose.

ADAMTS-5 Decreases in Aortas and Plasma From Aortic Dissection Patients and Alleviates Angiotensin II-Induced Smooth Muscle-Cell Apoptosis.

Background: Acute aortic dissection (AAD) is associated with degeneration of the aortic media and accompanied by vascular extracellular matrix (ECM) remodeling. Recently, a disintegrin and metalloproteinase with thrombospondin type 1 motifs-5 (ADAMTS-5) has been reported to be involved in ECM remodeling and vascular diseases. The aim of this study was to examine ADAMTS-5 levels in AAD patients and investigate the underlying mechanisms. Methods: Aortic tissue samples were collected from normal donors and AAD patients, and the expression of ADAMTS-5 was analyzed in all aortic tissues. In addition, plasma levels of ADAMTS-5, matrix metalloproteinase (MMP)-2 and MMP-9, and tumor necrosis factor-α (TNF-α) were measured in repeated samples from AAD patients and compared to the non-AAD (NAD) group. In addition, we investigated the effects of ADAMTS-5 in smooth muscle cell (SMC) apoptosis. Results: The results showed that ADAMTS-5 expression was significantly reduced in the aortas of AAD patients and that SMCs were the main source of ADAMTS-5. In addition, the plasma ADAMTS-5 level was lower, but plasma MMP-2, MMP-9, and TNF-α levels were increased in the AAD patients. Multivariate linear regression analyses showed that a decreased ADAMTS-5 level in patients was independently associated with an increased risk of AAD. Furthermore, recombinant human ADAMTS-5 significantly ameliorated angiotensin (Ang II)-evoked SMC apoptosis. Conclusions: ADAMTS-5 shows promise as a novel potential biomarker for AAD, and regulation of SMC is a possible mechanism for the effects of ADAMTS-5.

Circular RNA_101237 mediates anoxia/reoxygenation injury by targeting let­7a­5p/IGF2BP3 in cardiomyocytes.

Circular RNAs (circRNAs) serve important roles in cardiovascular diseases, including myocardial infarction. However, the mechanisms underlying the roles of circRNAs in cardiomyocyte death induced by anoxia/reoxygenation (A/R) are not fully understood. In the present study, the roles of circRNA_101237 and let­7a­5p in cardiomyocyte death induced by A/R injury were investigated. It was identified that circRNA_101237 was induced by A/R injury in a time­dependent manner and that circRNA_101237 knockdown protected cardiomyocytes from A/R­mediated apoptosis. Additional mechanistic studies revealed that circRNA_101237 served as a sponge for let­7a­5p, subsequently regulating insulin­like growth factor 2 mRNA­binding protein 3 (IGF2BP3)­dependent autophagy. IGF2BP3 downregulation decreased the levels of apoptosis and inhibited autophagy induced by A/R challenge in primary cardiomyocytes. These results identified circRNA_101237 as a novel circRNA that regulates cardiomyocyte death and autophagy, and demonstrated that the circRNA­101237/let­7a­5p/IGF2BP3 axis, which serves as a regulator of cardiomyocyte death, may be a potential therapeutic target for the management of cardiovascular diseases.

Thrombospondin 1 Is Increased in the Aorta and Plasma of Patients With Acute Aortic Dissection.

BACKGROUND: Previous studies have shown that thrombospondin 1 (TSP-1) is involved in cardiovascular diseases, such as atherosclerosis and abdominal aortic aneurysm. However, TSP-1 expression levels in human aortic dissection (AD) remain unknown. METHODS: TSP-1 levels were detected in aortas collected from control subjects and AD patients. The TSP-1, interleukin (IL) 6, matrix metalloproteinase (MMP) 2, and MMP9 levels in plasma from non-AD patients and AD patients were measured. In addition, the effects of recombinant mouse TSP-1 protein on macrophage differentiation and smooth muscle cell (SMC) apoptosis were investigated. RESULTS: Compared with the aortas from control subjects, aortas from AD patients showed a significant increase in TSP-1 expression, especially in the torn sections. SMCs and endothelial cells produced TSP-1, but SMCs were the main source. TSP-1, IL-6, MMP2, and MMP9 levels were higher in AD patients than in non-AD patients, and plasma IL-6, MMP2, and MMP9 levels were positively correlated with TSP-1 levels in AD patients. Simple linear regression analysis and multivariate linear regression analysis showed that TSP-1 levels were independently correlated with the onset of AD. In cultured cells, recombinant mouse TSP-1 further increased inducible nitric oxide synthase (iNOS) mRNA expression in angiotensin (Ang) II-treated macrophages, whereas it reduced B-cell lymphoma-2 (Bcl2) mRNA levels and increased Bcl2-associated X protein (Bax) mRNA levels in Ang II-treated SMCs. CONCLUSIONS: TSP-1 level is significantly increased in AD patients and might participate in AD via promoting classically activated macrophage (M1) macrophage differentiation and SMC apoptosis.

Epidemiology and Serum Metabolic Characteristics of Acute Myocardial Infarction Patients in Chest Pain Centers.

BACKGROUND: We aimed to find a potential earlier diagnostic strategy for acute myocardial infarction (AMI) by investigating the epidemiology and serum metabolic characteristics of AMI patients in comparison with those of chest pain controls (CPCS). METHODS: We conducted this prospective, non-randomized, observational study of patients with acute chest pain symptoms presenting to the Emergency Rooms (ER) in The People's Hospital of Guangxi Zhuang Autonomous Region, Nanning, Guangxi Province, China from January 2015 to July 2016. We included a cohort of 45 patients with AMI together with 45 age- and sex-matched CPCS. The epidemiology of AMI was collected, and the phenotypic characteristics of the serum metabolite composition of AMI patients were determined using a combination of 1H nuclear magnetic resonance (NMR)-based metabolomics and clinical assays. RESULTS: The epidemiology showed that elderly AMI patients with chest pain syndrome presenting to ER have little awareness of their physical condition and compliance with medication. Significant serum metabolic differences observed between AMI patients and CPCS were highlighted by system differentiations in multiple metabolic pathways including anaerobic glycolysis, gluconeogenesis, tricarboxylic acid cycle (TCA cycle), protein biosynthesis, lipoprotein changes, choline and fatty acid metabolisms and intestinal microbial metabolism. CONCLUSION: The epidemiology and serum metabolic phenotypes observed here demonstrated that integration of metabolomics with other techniques could be useful for better understanding the biochemistry of AMI and for potential AMI molecular diagnosis. We should improve the general public's awareness of AMI, including early symptoms, risk factors, emergency responses, and treatments for related comorbidities.

Cytokines in aortic dissection.

Aortic dissection (AD) is one of the most dangerous forms of vascular disease, characterized by endometrial rupture and intramural hematoma formation. Generally, the pathological process is complicated and closely related to the infiltration of inflammatory cells into the aortic wall and apoptosis of vascular smooth muscle cells. Currently, multiple cytokines, including interleukins, interferon, the tumor necrosis factor superfamily, colony stimulating factor, chemotactic factor, growth factor and so on, have all been demonstrated to play a critical role in AD. Additionally, studies of the link between cytokines and AD could deepen our understanding of the disease and may guide future treatment therapies; therefore, this review focuses on the role of cytokines in AD.

Rosuvastatin suppresses platelet-derived growth factor-BB-induced vascular smooth muscle cell proliferation and migration via the MAPK signaling pathway.

An imbalance in the proliferation and migration of vascular smooth muscle cells (VSMCs) is significant in the onset and progression of vascular diseases, including arteriosclerosis and restenosis subsequent to vein grafting or coronary intervention. Rosuvastatin, a selective inhibitor of hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase, has pharmacological properties including the ability to reduce low-density lipoprotein-cholesterol (LDL-C) and very low-density lipoprotein-cholesterol (VLDL-C) levels, slow atherosclerosis progression and improve coronary heart disease outcomes. However, little is known concerning the molecular mechanism by which rosuvastatin affects vascular cell dynamics. In this study, we studied the inhibitory role of rosuvastatin on platelet-derived growth factor-BB (PDGF-BB)-induced VSMC proliferation and migration, as well as the molecular mechanisms involved. MTT data showed that rosuvastatin markedly inhibited the proliferation of PDGF-BB-induced VSMCs in a time-dependent manner. VSMCs are able to dedifferentiate into a proliferative phenotype in response to PDGF-BB stimulation; however, rosuvastatin effectively attenuated this phenotype switching. Moreover, we also showed that rosuvastatin significantly suppressed PDGF-BB-induced VSMC migration, which may be a result of its inhibitory effect on the protein expression of matrix metalloproteinase-2 (MMP2) and MMP9. Investigation into the molecular mechanisms involved revealed that rosuvastatin inhibited the mitogen-activated protein kinase (MAPK) signaling pathway by downregulating extracellular signal-regulated kinase (ERK) and p38 MAPK, although the phosphorylation level of c-Jun N-terminal kinase (c-JNK) was not altered following rosuvastatin treatment. In conclusion, the present study showed that rosuvastatin suppressed PDGF-BB-induced VSMC proliferation and migration, indicating that rosuvastatin has the potential to become a promising therapeutic agent for the treatment of atherosclerosis and restenosis.