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881.
Yuan Zhou Meigui Wang Jing Zhang Peng Xu Haitao Wang 《Journal of cellular physiology》2020,235(12):9414-9423
Various research studies have been conducted in deducing the role of microRNAs (miRNAs) in the pathogenesis and physiological processes of various systematic diseases. This study aims at demonstration of the important role played by miR-29a-3p, through association with phosphatase and tensin homolog (PTEN), in the regulation of abdominal aortic aneurysm development and progression. Quantitative real-time polymerase chain reaction (RT-qPCR) examined miRNA-19a-3p and PMEPA1 expression in multiplied vascular smooth muscle cells (VSMCs). Cell transfection upregulated or downregulated the genes and cell counting kit-8 assay determined cellular viability. RT-qPCR detected cellular proliferation and cell death using the cell proliferation and apoptosis biomarkers Ki87 and proliferating cell nuclear antigen, caspase-8 and caspase-3, respectively. Furthermore, luciferase assay analyzed the luciferase activity and western blot analysis determined miRNA-19a-3p and PMEPA1 protein expression in proliferation and apoptosis biomarkers. TargetScan 4.2 online software ( www.targetscan.org ) was used to perform the bioinformatics analysis so as to forecast the putative targets of miR-29a-3p and PTEN. The results inferred that there was an increased expression of miRNA-29a-3p found in AAA-mimic cells with increased cellular viability and significant pathological apoptosis. Further, when the expression of miRNA-29a-3p was downregulated, it reduced the cell viability of AAA cells. On the basis of the gene interplays, it can be understood that the PTEN was directly targeted by miRNA-29a-3p so as to regulate the AAA progression. Thus, PTEN was found to strengthen the proliferation effect of miRNA-29a-3p in AAA cells. The current study thus shed more insights about the molecular mechanistic roles of miRNA-29a-3p and PTEN, opening doors for novel therapeutic approach to AAA. 相似文献
882.
Jingwen Li Jing Zou Xiaoyue Wan Chunyan Sun Zhangbo Chu Yu Hu 《Journal of cellular physiology》2020,235(11):7681-7695
Despite the administration of new effective drugs in recent years, relapse and drug resistance are still the main obstacles in multiple myeloma (MM) treatment, making MM an incurable disease. To overcome drug resistance in MM, it is critical to understand the underlying mechanisms of malfunctioning gene expression and develop novel targeted therapies. During the past few decades, with the discovery and characterization of noncoding RNAs (ncRNAs), the landscape of dysregulated ncRNAs of cancers as well as their biological and pathobiological functions in tumorigenesis and drug resistance have been recognized. Studies about ncRNAs improved the understanding of variations of drug response among individuals at a level distinguished from genetic polymorphism, and provided with new orientations for targeted therapies. In this review, we will summarize the emerging impact and underlying molecular mechanisms of the most relevant classes of ncRNAs in drug resistance of MM, and discuss the potential as well as strategies of treating ncRNAs as therapeutic targets. 相似文献
883.
暗黑菌门包括OP9和JS1两大分支,成员大多为未培养微生物,在自然环境中广泛分布,并且在部分环境如厌氧海洋沉积物、地热环境以及油藏中为优势微生物。基于基因组信息的研究表明,暗黑菌为严格的厌氧微生物,同时具有降解糖类、小分子酸、短链正构烷烃的能力,在地球碳循环过程中可能扮演着重要的角色。然而,由于缺乏相应代表性的纯培养菌株,对于暗黑菌的生理生化功能推测仍有待验证。文章概述了暗黑菌的发现及发展历史,分析了其环境分布和多样性,简述了目前提出的三种代谢方式,提出了未来暗黑菌的研究发展方向。 相似文献
884.
Jorge Angelini Ghio Silvina Tania Taurian Fernando Ibáñez María Laura Tonelli Lucio Valetti María Soledad Anzuay Liliana Ludueña Vanina Muñoz Adriana Fabra 《Archives of microbiology》2013,195(10-11):683-692
In the peanut production, the applications of herbicides and fungicides are a common practice. In this work, studies done under field conditions demonstrated that pesticides affected negatively the number and nitrogenase activity of diazotrophic populations of soil. Agrochemical effects were not transient, since these parameters were not recovered to pre-treatment levels even 1 year after pesticides application. Results obtained from greenhouse experiments revealed that the addition of herbicide or fungicides diminished the free-living diazotrophs number reaching levels found in soil amended with the pesticides and that the number of symbiotic diazotrophs was not affected by the insecticide assayed. The soil nitrogenase activity was not affected by fungicides and glyphosate. The effect of pesticides on the nitrogen-fixing bacteria diversity was evaluated both in field and greenhouse experiments. Analysis of clone libraries generated from the amplification of soil nifH gene showed a diminution in the genetic diversity of this bacterial community. 相似文献
885.
886.
887.
Atanas G. Atanasov Jian N. Wang Shi P. Gu Jing Bu Matthias P. Kramer Lisa Baumgartner Nanang Fakhrudin Angela Ladurner Clemens Malainer Anna Vuorinen Stefan M. Noha Stefan Schwaiger Judith M. Rollinger Daniela Schuster Hermann Stuppner Verena M. Dirsch Elke H. Heiss 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
Peroxisome proliferator-activated receptor gamma (PPARγ) agonists are clinically used to counteract hyperglycemia. However, so far experienced unwanted side effects, such as weight gain, promote the search for new PPARγ activators.Methods
We used a combination of in silico, in vitro, cell-based and in vivo models to identify and validate natural products as promising leads for partial novel PPARγ agonists.Results
The natural product honokiol from the traditional Chinese herbal drug Magnolia bark was in silico predicted to bind into the PPARγ ligand binding pocket as dimer. Honokiol indeed directly bound to purified PPARγ ligand-binding domain (LBD) and acted as partial agonist in a PPARγ-mediated luciferase reporter assay. Honokiol was then directly compared to the clinically used full agonist pioglitazone with regard to stimulation of glucose uptake in adipocytes as well as adipogenic differentiation in 3T3-L1 pre-adipocytes and mouse embryonic fibroblasts. While honokiol stimulated basal glucose uptake to a similar extent as pioglitazone, it did not induce adipogenesis in contrast to pioglitazone. In diabetic KKAy mice oral application of honokiol prevented hyperglycemia and suppressed weight gain.Conclusion
We identified honokiol as a partial non-adipogenic PPARγ agonist in vitro which prevented hyperglycemia and weight gain in vivo.General significance
This observed activity profile suggests honokiol as promising new pharmaceutical lead or dietary supplement to combat metabolic disease, and provides a molecular explanation for the use of Magnolia in traditional medicine. 相似文献888.
889.
890.
Bo Wang Lian Li Yuan Liao Jinqing Li Xingjuan Yu Yi Zhang Jing Xu Huilan Rao Shupeng Chen Lanjun Zhang Limin Zheng 《Cancer immunology, immunotherapy : CII》2013,62(10):1575-1585
The proinflammatory cytokine interleukin 17 (IL-17) is considered to play a crucial role in diverse human tumors; however, its role in disease progression remains controversial. This study investigated the cellular source and distribution of IL-17 in esophageal squamous cell carcinoma (ESCC) in situ and determined its prognostic value. Immunohistochemistry, immunofluorescence and immunoelectron microscopy were used to identify IL-17-expressing cells in ESCC tissues, paying particular attention to their anatomic localization. Kaplan–Meier analysis and Cox proportional hazards regression models were applied to estimate overall survival in 215 ESCC patients with long-term follow-up (>10 years). The results showed that mast cells, but not T cells or macrophages, were the predominant cell type expressing IL-17 in ESCC tissues. Unexpectedly, these IL-17+ cells were highly enriched in the muscularis propria rather than the corresponding tumor nest (p < 0.0001). The density of IL-17+ cells in muscularis propria was inversely associated with tumor invasion (p = 0.016) and served as an independent predictor of favorable survival (p = 0.007). Moreover, the levels of IL-17+ cells in muscularis propria were positively associated with the density of effector CD8+ T cells and activated macrophages in the same area (both p < 0.0001). This finding suggested that mast cells may play a significant role in tumor immunity by releasing IL-17 at a previously unappreciated location, the muscularis propria, in ESCC tissues, which could serve as a potential prognostic marker and a novel therapeutic target for ESCC. 相似文献