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91.
Wenkang Luan Xuanfeng Zhang Hongru Ruan Jinlong Wang Xuefeng Bu 《Journal of cellular physiology》2019,234(9):16609-16618
The long noncoding RNA (lncRNA) OIP5-AS1 has been considered to promote the growth and metastasis of many human tumors. However, the role of OIP5-AS1 in melanoma has not been reported. In this study, we found that OIP5-AS1 levels were significantly elevated in melanoma tissue and that high OIP5-AS1 expression was an independent risk factor for the poor survival of patients with melanoma. miR-217 suppressed glutamine catabolism in melanoma cells by targeting glutaminase (GLS), the rate-limiting enzyme of glutamine catabolism. We also demonstrated that OIP5-AS1 acted as a sponge of miR-217 to upregulate GLS expression, thus promoting glutamine catabolism and melanoma growth. Overall, this result elucidates a new mechanism for OIP5-AS1 in metabolism in melanoma and provides a potential therapeutic target for patients with melanoma. 相似文献
92.
Xinpan Chen Yiru Wu Zongli Diao Xue Han Dishan Li Xiongzhong Ruan Wenhu Liu 《Journal of cellular physiology》2019,234(12):22352-22364
C1q/tumor necrosis factor-related protein-3 (CTRP3) has been extensively reported as an important role involved in antifibrosis, antiapoptosis, and anti-inflammation. However, the role of CTRP3 involved in renal fibrosis remains unclear. Our current study explored the role of CTRP3 in renal fibrosis and its underlying mechanisms by using serums and renal biopsy specimens from renal fibrosis patients and control subjects, rats models with the surgery of unilateral ureteral obstruction (UUO) and human renal proximal tubular epithelial cells (HRPTEpiCs). We found that circulating levels of CTRP3 had no significant difference between renal fibrosis patients and healthy subjects; however, renal CTRP3 expression was markedly downregulated in the fibrotic region with an abundant expression of collagen-I. In UUO rat models, circulating levels of CTRP3 have not changed with the prolonged obstruction of the kidney; renal CTRP3 expression was decreased with the severity of renal fibrosis; adenovirus-mediated CTRP3 treatment inhibited renal interstitial fibrosis. In vitro experiments revealed that CTRP3 attenuates TGF-β1 induced tubular epithelial cells fibrotic changes; CTRP3 knockdown facilitates the expression of fibrotic markers in TGF-β1-induced HRPTEpiCs; recombinant CTRP3 or adenovirus-mediated CTRP3 overexpression significantly inhibited the Notch signaling pathway-associated factors, and knockdown of CTRP3 increased TGF-β1-mediated activation of the Notch signaling pathways. Collectively, our current study found that CTRP3 could improve renal fibrosis, to some extent, through inhibiting the Notch pathway. 相似文献
93.
[目的]探究慢生型花生根瘤菌III型分泌系统在花生-根瘤菌互作的功能。[方法]本研究采用同源重组和三亲本接合转移的方法,构建Bradyrhizobium sp.MZ5的III型分泌系统调节基因ttsI突变体;荧光定量PCR检测添加大豆苷元(Daidzein)和染料木黄酮(Genistein)诱导物后野生型和突变株转录水平上ttsI的表达量变化及其差异;蛭石结瘤实验分析ttsI基因突变对花生结瘤能力的影响。[结果]在转录水平上,大豆苷元和染料木黄酮对MZ5的III型分泌系统调节基因ttsI的表达具有显著的抑制作用(P<0.05)。在MZ5△ttsI突变体中ttsI基因的表达量都明显下调,与野生型菌株的相比都达到极显著水平(P<0.001)。蛭石结瘤实验表明,与野生型菌株相比,MZ5△ttsI突变体在不同花生品种的结瘤数和地上部干重都显著性降低。根瘤石蜡切片表明,MZ5△ttsI突变体在根瘤内的含菌量少于野生型菌株。[结论]Bradyrhizobium sp.MZ5菌株中的III型分泌系统在花生-根瘤菌互作中对结瘤有积极的促进作用。 相似文献
94.
Ronghua Yang Jingru Wang Ziheng Zhou Shaohai Qi Shubin Ruan Zepeng Lin Qi Xin Yan Lin Xiaodong Chen Julin Xie 《Developmental biology》2019,445(2):271-279
Local transplantation of stem cells has therapeutic effects on skin damage but cannot provide satisfactory wound healing. Studies on the mechanisms underlying the therapeutic effects of stem cells on skin wound healing will be needed. Hence, in the present study, we explored the role of Caveolin-1 in epidermal stem cells (EpiSCs) in the modulation of wound healing. We first isolated EpiSCs from mouse skin tissues and established stable EpiSCs with overexpression of Caveolin-1 using a lentiviral construct. We then evaluated the epidermal growth factor (EGF)-induced cell proliferation ability using cell counting Kit-8 (CCK-8) assay and assessed EpiSC pluripotency by examining Nanog mRNA levels in EpiSCs. Furthermore, we treated mice with skin burn injury using EpiSCs with overexpression of Caveolin-1. Histological examinations were conducted to evaluate re-epithelialization, wound scores, cell proliferation and capillary density in wounds. We found that overexpression of Caveolin-1 in EpiSCs promoted EGF-induced cell proliferation ability and increased wound closure in a mouse model of skin burn injury. Histological evaluation demonstrated that overexpression of Caveolin-1 in EpiSCs promoted re-epithelialization in wounds, enhanced cellularity, and increased vasculature, as well as increased wound scores. Taken together, our results suggested that Caveolin-1 expression in the EpiSCs play a critical role in the regulation of EpiSC proliferation ability and alteration of EpiSC proliferation ability may be an effective approach in promoting EpiSC-based therapy in skin wound healing. 相似文献
95.
Ruan Hong Xiao Renshun Jiang Xinghai Zhao Biao Wu Kai Shao Zongzuan Zhang Zhongjie Duan Huyang Song Yulin 《Molecular and cellular biochemistry》2019,450(1-2):199-207
Molecular and Cellular Biochemistry - Bone marrow mesenchymal stem cells (BMSCs) are multipotential differentiation cells which can differentiate into different cell types such as osteoblasts,... 相似文献
96.
97.
Xue Li Xi Lv Yanping Lin Junfeng Zhen Cao Ruan Wei Duan Yue Li Jianping Xie 《Journal of cellular biochemistry》2019,120(8):12197-12207
The typical two-component regulatory systems (TCSs), consisting of response regulator and histidine kinase, play a central role in survival of pathogenic bacteria under stress conditions such as nutrient starvation, hypoxia, and nitrosative stress. A total of 11 complete paired two-component regulatory systems have been found in Mycobacterium tuberculosis, including a few isolated kinase and regulatory genes. Increasing evidence has shown that TCSs are closely associated with multiple physiological process like intracellular persistence, pathogenicity, and metabolism. This review gives the two-component signal transduction systems in M. tuberculosis and their signal transduction roles in adaption to the environment. 相似文献
98.
This study was carried out to examine the effects of the meiosis-activating C(29) sterol, 4,4-dimethyl-5 alpha-cholesta-8,14, 24-trien-3 beta-ol (FF-MAS), on mouse oocyte maturation in vitro. Cumulus cell-enclosed oocytes (CEO) and denuded oocytes (DO) from hormonally primed, immature mice were cultured 17-18 h in minimum essential medium (MEM) containing 4 mM hypoxanthine plus increasing concentrations of FF-MAS. The sterol induced maturation in DO with an optimal concentration of 3 microg/ml but was without effect in CEO, even at concentrations as high as 10 microg/ml. Some stimulation of maturation in hypoxanthine-arrested CEO was observed when MEM was replaced by MEMalpha. Interestingly, the sterol suppressed the maturation of hypoxanthine-arrested CEO in MEM upon removal of glucose from the medium. FF-MAS also failed to induce maturation in DO when meiotic arrest was maintained with dibutyryl cAMP (dbcAMP). The rate of maturation in FF-MAS-stimulated, hypoxanthine-arrested DO was slow, as more than 6 h of culture elapsed before significant meiotic induction was observed, and this response required the continued presence of the sterol. Although the oocyte took up radiolabeled lanosterol, such accumulation was restricted by the presence of cumulus cells. In addition, lanosterol failed to augment FSH-induced maturation and was even inhibitory at a high concentration. Moreover, the downstream metabolite, cholesterol, augmented the inhibitory action of dbcAMP on maturation in both CEO and DO. Two inhibitors of 14 alpha-demethylase, ketoconazole, and 14 alpha-ethyl-5 alpha-cholest-7-ene-3 beta, 15 alpha-diol that can suppress FF-MAS production from lanosterol failed to block consistently FSH-induced maturation. These results confirm the stimulatory action of FF-MAS on hypoxanthine-arrested DO but do not support a universal meiosis-inducing function for this sterol. 相似文献
99.
100.
Ruan B Wilson WK Pang J Gerst N Pinkerton FD Tsai J Kelley RI Whitby FG Milewicz DM Garbern J Schroepfer GJ 《Journal of lipid research》2001,42(5):799-812
Smith-Lemli-Opitz syndrome (SLOS) is a hereditary disorder in which a defective gene encoding 7-dehydrocholesterol reductase causes the accumulation of noncholesterol sterols, such as 7- and 8-dehydrocholesterol. Using rigorous analytical methods in conjunction with a large collection of authentic standards, we unequivocally identified numerous noncholesterol sterols in 6 normal and 17 SLOS blood samples. Plasma or erythrocytes were saponified under oxygen-free conditions, followed by multiple chromatographic separations. Individual sterols were identified and quantitated by high performance liquid chromatography (HPLC), Ag(+)-HPLC, gas chromatography (GC), GC-mass spectrometry, and nuclear magnetic resonance. As a percentage of total sterol content, the major C(27) sterols observed in the SLOS blood samples were cholesterol (12;-98%), 7-dehydrocholesterol (0.4;-44%), 8-dehydrocholesterol (0.5;-22%), and cholesta-5,7,9(11)-trien-3beta-ol (0.02;-5%), whereas the normal blood samples contained <0.03% each of the three noncholesterol sterols. SLOS and normal blood contained similar amounts of lathosterol (0.05;-0.6%) and cholestanol (0.1;-0.4%) and approximately 0.003;-0.1% each of the Delta(8), Delta(8(14)), Delta(5,8(14)), Delta(5,24), Delta(6,8), Delta(6,8(14)), and Delta(7,24) sterols.The results are consistent with the hypothesis that the Delta(8(14)) sterol is an intermediate of cholesterol synthesis and indicate the existence of undescribed aberrant pathways that may explain the formation of the Delta(5,7,9(11)) sterol. 19-Norcholesta-5,7,9-trien-3beta-ol was absent in both SLOS and normal blood, although it was routinely observed as a GC artifact in fractions containing 8-dehydrocholesterol. The overall findings advance the understanding of SLOS and provide a methodological model for studying other metabolic disorders of cholesterol synthesis. 相似文献