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911.
Vascular calcification is highly prevalent in patients with type 2 diabetes mellitus (T2DM), one of the most common chronic diseases with high morbidity and mortality. In recent years, microRNAs have been widely reported as potential biomarkers for the diagnosis and treatment of T2DM. We hypothesized that miR-128-3p is associated with cardiovascular calcification and insulin resistance (IR) in rats with T2DM by targeting ISL1 via the Wnt pathway. Microarray analysis was adopted to identify differentially expressed genes related to T2DM. T2DM models were induced in rats. Blood samples from normal and T2DM rats were used to detect islet β-cell function, islet sensitivity, and calcium content. Next, islet tissues were obtained to identify the expression of miR-128-3p, ISL1, and the Wnt signaling pathway- and apoptosis-related genes. Finally, apoptosis of islet β-cells was determined by flow cytometry. Through microarray analysis of GSE27382 and GSE23343, ISL1 was found to be downregulated in T2DM. In blood samples from T2DM rats, basic biochemical indicators, IR, and calcium content were increased, and islet sensitivity and islet β-cell function were decreased. Furthermore, upregulation of miR-128-3p and ISL1 gene silencing promoted the expression of Wnt-1, β-catenin, GSK-3β, and Bax and the phosphorylation of β-catenin and GSK-3β, inhibited c-fos, PDX-1, and Bcl-2 expression, and enhanced cell apoptosis. The key findings of our study demonstrate that miR-128-3p aggravates cardiovascular calcification and IR in T2DM rats by downregulating ISL1 through the activation of the Wnt pathway. Thus, miR-128-3p may serve as a potential target for the treatment of T2DM.  相似文献   
912.
913.
914.
The mechanism of local inflammation and systemic injury in chronic periodontitis is complicated, in which and exosomes play an important role. In our study, we found that T helper cell 17 (Th17)/regulatory T cell (Treg) balance is destabilized in the peripheral blood of patients with periodontitis, with upregulated Th17 or downregulated Treg, respectively. Porphyromonas gingivalis lipopolysaccharide (LPS) was used to simulate the inflammatory microenvironment of chronic periodontitis. The exosomes were extracted from periodontal ligament stem cells (PDLSCs) in LPS-induced periodontitis environment, which inversely effected on CD4+ T cells under normal and inflammatory conditions. Furthermore, compared with exosomes from normal PDLSCs, lower expression of microRNA-155-5p (miR-155-5p) and higher expression of Sirtuin-1 (SIRT1) were observed in exosomes from LPS-stimulated PDLSCs. Exosomes from PDLSCs alleviated inflammatory microenvironment through Th17/Treg/miR-155-5p/SIRT1 regulatory network. This study aimed to find the “switching” factors that affected the further deterioration of periodontitis to maximally control the multiple downstream damage signal factors to further understand periodontitis and find new targets for its treatment.  相似文献   
915.
Resistance towards imatinib (IM) remains troublesome in treating many chronic myeloid leukemia (CML) patients. Heme oxygenase-1 (HO-1) is a key enzyme of antioxidative metabolism in association with cell resistance to apoptosis. Our previous studies have shown that overexpression of HO-1 resulted in resistance development to IM in CML cells, while the mechanism remains unclear. In the current study, the IM-resistant CML cells K562R indicated upregulation of some of the histone deacetylases (HDACs) compared with K562 cells. Therefore, we herein postulated HO-1 was associated with HDACs. Silencing HO-1 expression in K562R cells inhibited the expression of some HDACs, and the sensitivity to IM was increased. K562 cells transfected with HO-1 resisted IM and underwent obvious some HDACs. These findings related to the inhibitory effects of high HO-1 expression on the reactive oxygen species (ROS) signaling pathway that negatively regulated HDACs. Increased expression of HO-1 activated HDACs by inhibiting ROS production. In summary, HO-1, which is involved in the development of drug resistance in CML cells by regulating the expression of HDACs, is probably a novel target for improving CML therapy.  相似文献   
916.
The molecular mechanism of liver fibrosis caused by hepatitis C virus (HCV) is not clear. The aim of this study is to understand the molecular mechanism of liver fibrosis induced by HCV and to identify potential therapeutic targets for hepatic fibrosis. We analyzed gene expression patterns between high liver fibrosis and low liver fibrosis samples, and identified genes related to liver fibrosis. We identified TAF1, HNF4A, and CALM2 were related to the development of liver fibrosis. HNF4A is important for hepatic fibrogenesis, and upregulation of HNF4A is an ideal choice for treating liver fibrosis. The gene expression of CALM2 is significantly lower in liver fibrosis samples than nonfibrotic samples. TAF1 may serve as a biomarker for liver fibrosis. The results were further validated by an independent data set GSE84044. In summary, our study described changes in the gene expression during the occurrence and development of liver fibrosis. The TAF1, HNF4A, and CALM2 may serve as novel targets for the treatment of liver fibrosis.  相似文献   
917.
Nephrolithiasis is a common disease of the urinary system, of which idiopathic calcium oxalate (CaOx) kidney stones, in particular, are one of the special types. In the initial stages of CaOx kidney stone formation, Randall's plaques (RPs) develop. Liver X receptors (LXRs) inhibit oxidative stress and inflammatory in other diseases; nevertheless, the role of LXRs in nephrolithiasis has yet to be elucidated. In this study, the role of LXRs in the progression of RP formation was investigated. Microarray analysis revealed that LXR/RXR levels were significantly greater in low-plaque tissues (<5%) than in high-plaque tissues (>5%), confirming the link between LXR activation and RP formation. Correspondingly, expression levels of two LXR target genes, LXRα and LXRβ, were lower in high-plaque tissues than in low-plaque tissues. In vitro, LXR agonist alleviated calcium oxalate monohydrate-induced cellular calcium deposits and apoptosis. LXR activation decreased reactive oxygen species production and gene expression of inflammatory mediators, including osteopontin that has recently been demonstrated to correlate with the development of RPs. Moreover, p38 MAPK and JNK signaling may mediate LXR-regulated expression in HK-2 cells. In an animal model, the deposition was reduced by activating LXR, and osteopontin expression was also inhibited. Our findings suggest a role for LXRs in the progression of idiopathic CaOx kidney stones; LXR agonists may have therapeutic potential for the treatment of nephrolithiasis.  相似文献   
918.
919.
Tumor suppressor long noncoding RNA maternally expressed gene 3 (lncRNA MEG3) exists in various cancers. Nonetheless, the functions of lncRNA MEG3 in choriocarcinoma (CC) are still not well studied. We explored the effects of lncRNA MEG3 on human CC JEG-3 and BeWo cells. lncRNA MEG3 was overexpressed, and the effects of lncRNA MEG3 on cell viability, proliferation, apoptosis, migration, and invasion were assessed by the cell counting kit-8 assay, western blot analysis, flow cytometry (plus western blot analysis), and transwell assay (plus western blot analysis), respectively. Then, the expression level of miR-211 was detected by real-time quantitative polymerase chain reaction. After that, the effects of dysregulated microRNA-211 (miR-211) with overexpressing lncRNA MEG3 on JEG-3 cells and BeWo cells were testified. Western blot analysis was used to study the involvements of the signaling pathways in the lncRNA MEG3-associated modulation. We found that lncRNA MEG3 upregulation reduced cell viability, inhibited proliferation, migration and invasion, and promoted apoptosis. Expression of miR-211 was upregulated after lncRNA MEG3 overexpression. Effects of lncRNA MEG3 overexpression were augmented by miR-211 overexpression, while they were declined by miR-211 silencing. Phosphorylated levels of PI3K, AKT, and AMP-activated protein kinase (AMPK) were decreased by lncRNA MEG3 overexpression via regulation of miR-211. To sum up, lncRNA MEG3 could repress proliferation, migration and invasion, and promote apoptosis of JEG-3 and BeWo cells through upregulating miR-211. The PI3K/AKT and AMPK pathways were inhibited by lncRNA MEG3 overexpression via regulation of miR-211.  相似文献   
920.
Methotrexate (MTX), a widely used antimetabolite in paediatric cancer to treatment, has been widely reported to cause bone loss and bone marrow (BM) microvascular (particularly sinusoids) damage. Investigations must now investigate how MTX-induced bone loss and microvasculature damage can be attenuated/prevented. In the present study, we examined the potency of icariin, an herbal flavonoid, in reducing bone loss and the dilation/damage of BM sinusoids in rats caused by MTX treatment. Groups of young rats were treated with five daily MTX injections (0.75 mg/kg) with and without icariin oral supplementation until Day 9 after the first MTX injection. Histological analyses showed a significant reduction in the bone volume/tissue volume (BV/TV) fraction (%) and trabecular number in the metaphysis trabecular bone of MTX-treated rats, but no significant changes in trabecular thickness and trabecular spacing. However, the BV/TV (%) and trabecular number were found to be significantly higher in MTX + icariin-treated rats than those of MTX alone-treated rats. Gene expression analyses showed that icariin treatment maintained expression of osteogenesis-related genes but suppressed the induction of adipogenesis-related genes in bones of MTX-treated rats. In addition, icariin treatment attenuated MTX-induced dilation of BM sinusoids and upregulated expression of endothelial cell marker CD31 in the metaphysis bone of icariin + MTX-treated rats. Furthermore, in vitro studies suggest that icariin treatment can potentially enhance the survival of cultured rat sinusoidal endothelial cells against cytotoxic effect of MTX and promote their migration and tube formation abilities, which is associated with enhanced production of nitric oxide.  相似文献   
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