成静
阜外华中心血管病医院 急诊科
OBJECTIVE:MicroRNA (miR) therapeutics is a promising approach to manage coronary artery disease (CAD). Herein, this research was aimed to explore miR-181c-5p-related mechanisms in CAD through regulating SIRT1.METHODS:A CAD mouse model was established by feeding a high-fat diet in 8-week-old ApoE-/- mice. miR-181c-5p, SIRT1, and acetylated p65 levels in mouse myocardial tissues were evaluated by RT-qPCR and Western blot. Hemodynamic parameters included the maximum rising rate of the left ventricular pressure (lv + dp/dtmax) and the time values from the onset of contraction to dp/dtmax (t-dp/dtmax), while hemorheological indices included whole blood viscosity (low shear, middle shear, or high shear), plasma viscosity, hematocrit, and platelet adhesion were measured. Tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and IL-6 were detected. Mouse pathological changes, degree of fibrosis, and cardiomyocyte apoptosis in myocardial tissues were assessed by HE, Masson, and TUNEL staining, respectively. The targeting relationship between miR-181c-5p and SIRT1 was verified by bioinformatics tools, dual luciferase reporter gene assay, and RNA pull-down assays.RESULTS:In myocardial tissue of CAD mice, miR-181c-5p and acetylated p65 were upregulated while SIRT1 was downregulated. Downregulating miR-181c-5p or upregulating SIRT1 effectively ameliorated CAD by improving hemodynamics and hemorheology and reducing inflammation, pathological changes, degree of fibrosis, and cardiomyocyte apoptosis in myocardial tissues of mice. miR-181c-5p targeted SIRT1, and overexpression of SIRT1 relieved upregulated miR-181c-5p-induced injuries in CAD mice. Regulating miR-181c-5p and SIRT1 affected the acetylation of p65.CONCLUSION:Downregulation of miR-181c-5p may ameliorate myocardial pathological changes and cardiomyocyte apoptosis in CAD by upregulating SIRT1 expression and decreasing acetylated p65 levels.
Hellenic journal of cardiology : HJC = Hellenike kardiologike epitheorese 2023
Vascular smooth muscle cell (VSMC) accumulation and endothelial cell dysfunction are associated with pathogenesis of atherosclerosis. Long noncoding RNA taurine up-regulated gene 1 (TUG1) has been reported to play an important role in cardiovascular diseases, including atherosclerosis. However, the regulatory mechanism underlying TUG1 in atherosclerosis is far from understood. VSMC and human umbilical vein endothelial cells (HUVEC) stimulated by oxidized low-density lipoprotein (ox-LDL) were used as cellular model of atherosclerosis. Cell proliferation and apoptosis were detected by CCK-8, flow cytometry and Western blot. The expression levels of TUG1, microRNA (miR)-148b and insulin-like growth factor 2 (IGF2) were measured by quantitative real-time polymerase chain reaction or Western blot. The target association among TUG1, miR-148b and IGF2 was determined by luciferase reporter assay and RNA immunoprecipitation. The expression of TUG1 was increased in ox-LDL-treated VSMC and HUVEC. Silence of TUG1 inhibited proliferation and promoted apoptosis in ox-LDL-treated VSMC but induced proliferation promotion and apoptosis inhibition in HUVEC stimulated by ox-LDL. miR-148b was a target of TUG1 and its knockdown reversed the effect of TUG1 silence on proliferation and apoptosis of VSMC and HUVEC challenged by ox-LDL. IGF2 was a target of miR-148b and miR-148b regulated proliferation and apoptosis in ox-LDL-treated VSMC and HUVEC by targeting IGF2. TUG1 promoted IGF2 protein expression by sponging miR-148b. TUG1 knockdown attenuated ox-LDL-induced injury through regulating proliferation and apoptosis of VSMC and HUVEC by miR-148b/IGF2 axis, providing a novel mechanism for pathogenesis of atherosclerosis.
Life sciences 2020
Objective: To observe the expressions of periostin (Postn) in colon cancer tissues and cells, and to investigate its biological effect and mechanism in colon cancer cells. Methods: Real-time quantitative polymerase chain reaction (RT-qPCR) and western blot were used to detect the expressions of Postn, let-7a and miR-98 in 20 pairs of colon cancer tissues and adjacent normal tissues, colon cancer cell lines including SW480, HT-29, HCT-116 and human normal colon epithelial cell NCM460. Small interfering RNAs (siRNAs) of Postn, pcDNA3.1-Postn plasmids, let-7a mimic and its negative control let-7a mimic-NC, miR-98 mimic and its negative control miR-98 mimic-NC were transfected into HCT-116 cells. 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide (MTT) was used to detect cell viability. Flow cytometry was used to detect cell apoptosis. Luciferase reporter gene assay was used to determine the targeting relationship between miRNAs and Postn. Results: Compared with adjacent normal tissues, Postn expression was up-regulated (P<0.05) while let-7a/miR-98 expression was down-regulated (P<0.05) in colon cancer tissues. Compared with NCM460 cells, Postn expression was up-regulated (P<0.05) while let-7a/miR-98 expression was down-regulated (P<0.05) in SW480, HT-29 and HCT-116 cells. In colon cancer tissues, the expression of Postn was negatively correlated with the expressions of let-7a and miR-98 (r=-0.69, P<0.001; r=-0.80, P<0.001). Inhibition of Postn in vitro reduced the viability of HCT-116 cells [(53.73±7.63)%, P<0.05], increased the apoptotic rate [(22.88±3.40)%, P<0.05], enhanced the expression of epithelial-mesenchymal transition (EMT) marker E-cadherin (2.44±0.39, P<0.05), while down-regulated the expressions of N-cadherin and Vimentin (0.44±0.07 and 0.38±0.06, P<0.05). Overexpression of Postn in vitro enhanced the cell viability of HCT-116 cells [(134.41±8.82) %, P<0.05], decreased the expression of E-cadherin (0.55±0.09, P<0.05), increased the expressions of N-cadherin and Vimentin (2.93±0.42 and 2.24±0.34, P<0.05), but had no effect on the apoptotic rate (P>0.05). Overexpression of let-7a or miR-98 partially reversed the biological effects of Postn overexpression in colon cancer cells, which implicated that Postn was a target gene of let-7a/miR-98. Conclusions: Postn is a cancer-promoting molecule of colon cancer, and inhibition of Postn expression can increase the apoptotic rate of colon cancer cells and repress EMT. Postn expression and function is regulated by let-7a/miR-98.
Zhonghua zhong liu za zhi [Chinese journal of oncology] 2019
Objective: To investigate the expression of long non-coding RNA LINC00339 in colorectal cancer patients and its effect and mechanism on proliferation and apoptosis of colorectal cancer cells. Methods: A retrospective analysis of 158 pathology-confirmed colorectal cancer patients, who were enrolled from August 2015 to January 2017, was performed. LINC00339 expression in colorectal cancer tissues and adjacent colorectal sampleswas detected by Real-time PCR. The correlation between LINC00339 expression and clinicopathological features as well as the relationship between LINC00339 and microRNA (miR)-218 expression was assayed. The interaction between LINC00339 and miR-218 was further confirmed by dual luciferase report system. Downregulation of LINC00339 was performed by siRNA interference technology in LoVo and HCT116 cells. Real-time PCR was used to detect miR-218 expression. 3-(4,5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) analysis was carried out to examine cell viability. Flow cytometry was used to determine cell apoptosis. Additionally, LINC00339 siRNA and miR-218 antagomirs (anti-miR-218) were co-transfected into LoVo and HCT116 cells, and then cell viability and apoptosis were detected. Results: LINC00339 expression was significantly increased in colorectal cancer tissues compared with adjacent colorectal tissues (4.69±1.52 vs 1.02±0.38, P<0.05). LINC00339 expression was not related to the age and gender of patients (P>0.05), but was associated with TNM stage, lymphatic metastasis, tumor maximum diameters, and differentiation degree (all P<0.05). LINC00339 expression was negatively correlated with miR-218 expression in colorectal cancer tissues (P<0.05). miR-218 mimics remarkably suppressed the fluorescence intensity of wild-type LINC00339 plasmid (P=0.001), but did not affect the fluorescence intensity of the mutant ones(P=0.88). Knockdown of LINC00339 remarkably inhibited proliferation, but promoted apoptosis of LoVo and HCT116 cells (all P<0.05). Compared with cells transfected with LINC00339 siRNA only, downregulation of miR-218 elevated proliferation and decreased apoptosis of LoVoand HCT116 cells. Conclusions: LINC00339 expression is upregulated in colorectal cancer tissues and correlated with patients' clinicopathological features. LINC00339 promotes proliferation, and suppresses apoptosis of colorectal cancer cells via downregulating miR-218.
Zhonghua yi xue za zhi 2019