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In varicose veins, vascular smooth muscle cells (VSMCs) often show abnormal proliferative and migratory rates and phenotypic transition. This study aimed to investigate whether microRNA (miR)-202 and its potential target, peroxisome proliferator–activated receptor-γ coactivator-1α (PGC-1α), were involved in VSMC phenotypic transition. miR-202 expression was analyzed in varicose veins and in VSMCs conditioned with platelet-derived growth factor. The effect of miR-202 on cell proliferation and migration was assessed. Furthermore, contractile marker SM-22α, synthetic markers vimentin and collagen I, and PGC-1α were analyzed by Western blot analysis. The modulation of PGC-1α expression by miR-202 was also evaluated. In varicose veins and proliferative VSMCs, miR-202 expression was upregulated, with decreased SM-22α expression and increased vimentin and collagen I expression. Transfection with a miR-202 mimic induced VSMC proliferation and migration, whereas a miR-202 inhibitor reduced cell proliferation and migration. miR-202 mimic constrained luciferase activity in HEK293 cells that were cotransfected with the PGC-1α 3′-untranslated region (3′-UTR) but not those with mutated 3′-UTR. miR-202 suppressed PGC-1α protein expression, with no influence on its messenger RNA expression. PGC-1α mediated VSMC phenotypic transition and was correlated with reactive oxygen species production. In conclusion, miR-202 affects VSMC phenotypic transition by targeting PGC-1α expression, providing a novel target for varicose vein therapy.  相似文献   
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Kazakh sheep are seasonal estrous animals, and gonadotropin-releasing hormone (GnRH) is the key to fertility regulation. The nutritional level has a certain regulatory effect on estrous, and vitamin B folate plays a role in DNA methylation, directly participating in the process. The goal of this study was to determine whether folate is involved in GnAQ methylation and its effect on GnRH secretion. The hypothalamic neurons of Kazakh fetal sheep were treated with folate at concentrations of 0 mg/mL, 4 mg/mL, 40 mg/mL, and 80 mg/mL. GnAQ promoter methylation, DNMT1, GnAQ expression, and GnRH secretion following treatment with different concentrations of folate were analyzed. One CpG site was methylated in the GNAQ promoter with 40 mg/mL folic acid, and no CpG methylation was found in the other groups. GnAQ expression was related to folate concentration and showed a trend of increasing first and then decreasing. The GnRH expression level in the 40 mg/mL folate group was significantly higher than in the other three groups ( P < .05). These results demonstrate that the appropriate folate concentration promoted GANQ promoter methylation, which in turn affected GnRH secretion.  相似文献   
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As a first line medicine for malaria treatment, artesunate (ART) also shows antitumor potential. However, little is known about the effect of ART on the cancer cell epithelial-mesenchymal transition (EMT). In this study, we found that ART inhibited cell growth in SK-HEP1 and SM7721 hepatocellular carcinoma cell lines. A microarray was used to identify differentially expressed protein-coding RNAs (pcRNA) and long noncoding RNAs (lncRNA) between SK-HEP1 cells with and without ART treatment. A differentially expressed lncRNA—RP11, the most related to the EMT of liver cancer cells—RP11 was identified by abioinformatics method Overexpressing and silencing assays were used to verify the role of RP11 in cancer cell EMT. The levels of RP11- and EMT-related genes in liver cancer samples from 75 patients were detected by using qualitative polymerase chain reaction or immunohistochemistry. We identified 1334 pcRNAs and 1670 lncRNA with differential expression induced by ART. ART inhibits EMT, proliferation, migration, invasion, and adhesion of liver cancer cells. RP11 depresses the inhibitory effect of ART on cancer cell EMT. The level of RP11 is associated with cancer cell EMT and metastasis and survival rate of the patient. These data suggest that RP11-linking ART and cancer cell EMT are important for ART-inhibited metastasis of liver cancer.  相似文献   
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Acute liver failure (ALF) is a disease resulted from diverse etiology, which generally leads to a rapid degenerated hepatic function. However, transplantation bone marrow–derived mesenchymal stem cells (BMSCs) transplantation has been suggested to relieve ALF. Interestingly, microRNA-214 (miR-214) could potentially regulate differentiation and migration of BMSCs. The present study aims to inquire whether miR-214 affects therapeutic potential of BMSCs transplantation by targeting PIM-1 in ALF. 120 male Wistar rats were induced as ALF model rats and transplanted with BMSCs post-alteration of miR-214 or PIM-1 expression. Further experiments were performed to detect biochemical index (alanine aminotransferase [ALT], aspartate transaminase [AST], total bilirubin [TBiL]), and expression of miR-214, PIM-1, hepatocyte growth factor (HGF), caspase 3, tumor necrosis factor-α (TNF-α), and interleukin-10 (IL-10) in rat serum. Apart from the above detection, apoptosis of hepatocytes and Ki67 protein expression in hepatic tissues of rats were additionally assessed. After BMSCs transplantation with miR-214 inhibition, a decreased expression of ALT, AST, and TBiL yet an increased expression of HGF was shown, coupled with a decline in the expression of caspase 3, TNF-α, and IL-10. Meanwhile, alleviated hepatic injury and decreased apoptotic index of hepatic cells were observed and the positive rate of Ki67 protein expression was significantly increased. Moreover, miR-214 and caspase 3, TNF-α, and IL-10 decreased notably, while PIM-1 was upregulated in response to miR-214 inhibition. Strikingly, the inhibition of PIM-1 reversed effects triggered by miR-214 inhibition. These findings indicated that downregulation of miR-214 improves therapeutic potential of BMSCs transplantation by upregulating PIM-1 for ALF.  相似文献   
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