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101.
Huo Y Guo X Li H Xu H Halim V Zhang W Wang H Fan YY Ong KT Woo SL Chapkin RS Mashek DG Chen Y Dong H Lu F Wei L Wu C 《The Journal of biological chemistry》2012,287(25):21492-21500
Increasing evidence demonstrates the dissociation of fat deposition, the inflammatory response, and insulin resistance in the development of obesity-related metabolic diseases. As a regulatory enzyme of glycolysis, inducible 6-phosphofructo-2-kinase (iPFK2, encoded by PFKFB3) protects against diet-induced adipose tissue inflammatory response and systemic insulin resistance independently of adiposity. Using aP2-PFKFB3 transgenic (Tg) mice, we explored the ability of targeted adipocyte PFKFB3/iPFK2 overexpression to modulate diet-induced inflammatory responses and insulin resistance arising from fat deposition in both adipose and liver tissues. Compared with wild-type littermates (controls) on a high fat diet (HFD), Tg mice exhibited increased adiposity, decreased adipose inflammatory response, and improved insulin sensitivity. In a parallel pattern, HFD-fed Tg mice showed increased hepatic steatosis, decreased liver inflammatory response, and improved liver insulin sensitivity compared with controls. In both adipose and liver tissues, increased fat deposition was associated with lipid profile alterations characterized by an increase in palmitoleate. Additionally, plasma lipid profiles also displayed an increase in palmitoleate in HFD-Tg mice compared with controls. In cultured 3T3-L1 adipocytes, overexpression of PFKFB3/iPFK2 recapitulated metabolic and inflammatory changes observed in adipose tissue of Tg mice. Upon treatment with conditioned medium from iPFK2-overexpressing adipocytes, mouse primary hepatocytes displayed metabolic and inflammatory responses that were similar to those observed in livers of Tg mice. Together, these data demonstrate a unique role for PFKFB3/iPFK2 in adipocytes with regard to diet-induced inflammatory responses in both adipose and liver tissues. 相似文献
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104.
The alternative pathway in cucumber seedlings under low temperature stress was enhanced by salicylic acid 总被引:1,自引:0,他引:1
Tao Lei Hong Feng Xin Sun Qi-Lin Dai Fan Zhang Hou-Guo Liang Hong-Hui Lin 《Plant Growth Regulation》2010,60(1):35-42
The alternative pathway is a cyanide-resistant and non-phosphorylatory electron transport pathway in mitochondria of higher
plants. Alternative oxidase (AOX) is the terminal oxidase of this pathway. Our present study investigated the effect of exogenous
salicylic acid (SA) on alternative pathway in cucumber (Cucumis sativus L.) seedlings under low temperature stress. Results showed that during the process of low temperature stress, the alternative
pathway capacity was enhanced as AOX expression increased in SA pretreated seedlings. Compared with seedlings without SA pretreatment,
slower decrease of relative water content and lower levels of electrolyte leakage, H2O2 and malonyldialdehyde content were detected in SA pretreated seedlings. These results indicated that SA could alleviate the
injury caused by low temperature on cucumber seedlings. Since the special protective functions of alternative pathway and
AOX in plants, we suggested that the alternative pathway was related to SA-mediated plant resistance to environmental stresses
such as low temperature. 相似文献
105.
106.
Xin Li Chun-Shan Quan Hui-Ying Yu Jian-Hua Wang Sheng-Di Fan 《World journal of microbiology & biotechnology》2009,25(1):151-154
A novel compound CF66I produced by Burkholeria cepacia was investigated for its antifungal effects against Fusarium solani by three different fluorescent dyes. Dual staining with propidium iodide (PI) and fluorescein diacetate (FDA) demonstrated
high doses of CF66I (120.0 μg ml−1) killed the fungi by acting primarily on the cell membrane. However, at fungistatic concentration (20.0 μg ml−1) of this compound, microscopic observations revealed swelling hyphae with abnormal chitin deposition, as determined by Calcofluor
white (CFW) staining, which was indicative of the alterations in cell wall structure. In addition, inhibition of intracellular
esterases activity was observed. These results led us to conclude that low doses of CF66I probably inhibited the fungal growth
by interfering with the cell metabolic pathways. 相似文献
107.
Angiostatin production in cultivation of recombinant Pichia pastoris fed with mixed carbon sources 总被引:4,自引:0,他引:4
A recombinant strain of Pichia pastoris with a phenotype of MutS was used to produce angiostatin. Due to the low methanol consumption rate of this strain, both methanol and glycerol feedings, that produced oscillation in dissolved O2 concentration, were used during the expression phase to improve cell growth and angiostatin expression. However, enhanced cell growth led to nitrogen limitation that suppressed further production of angiostatin, but addition of ammonia allowed angiostatin concentration to reach 108 mg l–1 after an expression period of 96 h. The ratio of consumed glycerol to methanol of 1.5:1 (w/w) in the expression phase suggested that methanol played an important role in the metabolism of carbon sources. 相似文献
108.
半导体矿物介导非光合微生物利用光电子新途径 总被引:7,自引:0,他引:7
自然界中微生物按其能量代谢途径主要分为两种:光能营养微生物和化能营养微生物.化能营养微生物作为非光能营养微生物长期被排除在以日光为能量来源的能量利用途径之外.本文介绍了一种新的微生物能量利用途径,即非光能营养微生物通过半导体矿物光催化作用来利用太阳能进行生长.实验室模拟体系中,金属氧化物、金属硫化物等天然半导体矿物在模拟日光激发下产生的光电子促进了化能自养与异养微生物的生长.研究结果表明微生物的生长与光子能量和光子数量密切相关,同时不同波长光辐照下的微生物生长情况与矿物的光吸收谱相吻合.这一能量利用途径的光能-生物能转化效率为0.13‰-1.90‰.在含有天然半导体矿物与天然微生物的红壤体系中,进一步发现半导体矿物光催化能够明显改变环境微生物的种群结构.已有的研究揭示了一种新发现并极有可能长期在地球上存在的微生物能量利用途径,即通过自然界中半导体矿物日光催化作用产生的光电子能够促进非光能营养微生物的生长代谢活动. 相似文献
109.
110.
Cytoglobin, generated using genetic engineering method, is a kind of recombinant human stellate cell activation-associated
protein. We speculate that it could influence the development of hepatic fibrosis like Sellate cell activation-associated
protein which was discovered by Kawada et al. Therefore, we investigated its anti-fibrosis effect on liver both in vivo and
in vitro. During our research, we found that cytoglobin showed obvious effect compared with the control group on Thioacetamide-induced
liver fibrosis in SD rats, including significantly decrease in aspartate aminotransferase, Hyaluronic acid, laminin and collagen
I(Col I) levels in serum and hydroxyproline in livers, which are the important indices reflecting the degree of hepatic fibrosis.
Meanwhile, the viability of rat hepatic stellate cell line T6 (HSC-T6) cells was inhibited by cytoglobin and the apoptosis
induced by cytoglobin in HSC-T6 cells was detected by Annexin V/PI double staining. Activation of the caspase cascade including
caspase-3 for the intrinsic pathways was demonstrated. The results also showed that the expression of Bcl-2 protein decreased
whereas that of Bax protein increased, leading to an increase of the Bax/Bcl-2 ratio. Our results demonstrated that cytoglobin
exhibited anti-fibrosis activity on livers in vivo and in vitro, involving apoptosis induction. 相似文献