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51.
ChaoChien Chang KeeChin Sia JiaFeng Chang ChiaMo Lin ChuenMao Yang ITa Lee Thi Thuy Tien Vo KuoYang Huang WeiNing Lin 《Journal of cellular and molecular medicine》2022,26(14):3850
Obesity is a world‐wide problem, especially the child obesity, with the complication of various metabolic diseases. Child obesity can be developed as early as the age between 2 and 6. The expansion of fat mass in child age includes both hyperplasia and hypertrophy of adipose tissue, suggesting the importance of proliferation and adipogenesis of preadipocytes. The changed composition of gut microbiota is associated with obesity, revealing the roles of lipopolysaccharide (LPS) on manipulating adipose tissue development. Studies suggest that LPS enters the circulation and acts as a pro‐inflammatory regulator to facilitate pathologies. Nevertheless, the underlying mechanisms behind LPS‐modulated obesity are yet clearly elucidated. This study showed that LPS enhanced the expression of cyclooxygenase‐2 (COX‐2), an inflammatory regulator of obesity, in preadipocytes. Pretreating preadipocytes with the scavenger of reactive oxygen species (ROS) or the inhibitors of NADPH oxidase or p42/p44 MAPK markedly decreased LPS‐stimulated gene expression of COX‐2 together with the phosphorylation of p47phox and p42/p44 MAPK, separately. LPS activated p42/p44 MAPK via NADPH oxidase‐dependent ROS accumulation in preadipocytes. Reduction of intracellular ROS or attenuation of p42/p44 MAPK activation both reduced LPS‐mediated COX‐2 expression and preadipocyte proliferation. Moreover, LPS‐induced preadipocyte proliferation and adipogenesis were abolished by the inhibition of COX‐2 or PEG2 receptors. Taken together, our results suggested that LPS enhanced the proliferation and adipogenesis of preadipocytes via NADPH oxidase/ROS/p42/p44 MAPK‐dependent COX‐2 expression. 相似文献
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Shi-Jun Wang Zhen-Zhen Qiu Fu-Wei Chen An-Li Mao Jun-Chao Bai Ye-Jing Hong Zhong-Pan Zhang Wu-An Zhu Zhi-Wei Zhang Hao Zhou 《Cell death & disease》2022,13(6)
Recent studies have investigated the ability of extracellular vesicles (EVs) in regulating neighboring cells by transferring signaling molecules, such as microRNAs (miRs) in renal fibrosis. EVs released by bone marrow mesenchymal stem cells (BMSCs) contain miR-181d, which may represent a potential therapy for renal fibrosis. miR-181d has been speculated to regulate Krüppel-like factor 6 (KLF6), which activates the nuclear factor-kappa B (NF-κB) signaling pathway. Luciferase assays were performed to confirm the relationship between miR-181d and KLF6. Gain- and loss-of-function studies in vivo and in vitro were performed to assess the effect of BMSC-derived EVs (BMSC-EVs), which contained miR-181d, on KLF6, NF-κB, and renal fibrosis. Transforming growth factor-β (TGF-β)-induced renal tubular epithelial HK-2 cells were treated with EVs derived from BMSCs followed by evaluation of collagen type IV α1 (Col4α1), Collagen I and α-smooth muscle actin (α-SMA) as indicators of the extent of renal fibrosis. Renal fibrosis was induced in rats by unilateral ureteral obstruction (UUO) followed by the subsequent analysis of fibrotic markers. BMSC-EVs had higher miR-181d expression. Overexpression of miR-181d correlated with a decrease in KLF6 expression as well as the levels of IκBα phosphorylation, α-SMA, Col4α1, TGF-βR1 and collagen I in HK-2 cells. In vivo, treatment with miR-181d-containing BMSC-derived EVs was able to restrict the progression of fibrosis in UUO-induced rats. Together, BMSC-EVs suppress fibrosis in vitro and in vivo by delivering miR-181d to neighboring cells, where it targets KLF6 and inhibits the NF-κB signaling pathway.Subject terms: Cell biology, Biotechnology 相似文献
55.
松材线虫伴生细菌多样性的宏基组分析 总被引:2,自引:0,他引:2
摘要:【目的】松材线虫是松材线虫病的病原,且与其伴生细菌之间存在互作关系,它们构成一个微生态系统。本研究旨在揭示松材线虫-伴生细菌群落细菌多样性。【方法】采用16S rRNA基因文库和454测序对伴生细菌群落的宏基因组进行初步分析。【结果】依据97%序列相似性划分OTU(Operational Taxonomic Unit),构建的16S rRNA文库包含25个OTU,分别属于Alphaproteobacteria、Betaproteobacteria、Gammaproteobacteria和Bacter 相似文献
56.
保护三峡工程影响的珍稀濒危生物的经济价值评估 总被引:2,自引:0,他引:2
运用条件价值评估法, 基于三峡工程对珍稀濒危生物影响的现状和采取的保护措施, 设计了支付卡式调查问卷。通过调查我国31个省(自治区、直辖市)以国有单位为主的职工的支付意愿, 评估了保护三峡工程影响的珍稀濒危生物白鳍豚(Lipotes vexillifer)、白鲟(Psephurus gladius)、达氏鲟(Acipenser dabryanus)、胭脂鱼(Myxocyprinus asiaticus)、中华鲟(Acipenser sinensis)和荷叶铁线蕨(Adiantum reniforme var. sinense)、疏花水柏枝(Myricaria laxiflora)、川明参(Chuanminshen violaceum)的经济价值。回收有效问卷1,036份, 有70.08%的有效问卷反馈者愿意为保护三峡工程影响的这些珍稀濒危生物而支付费用, 平均支付意愿值为127.82元/年。同时采用列联表及卡方独立性检验方法重点分析了总样本各因素对支付意愿值的影响, 结果显示年龄、文化程度、从事职业、个人收入、对三峡工程的了解、对三峡工程的关注、对三峡工程对生物影响的了解等因素与支付意愿值显著相关。最后计算得出保护三峡工程影响的这些珍稀濒危生物的经济价值为82.19×108元/年。以上结果为进一步制定相关保护政策提供了依据。 相似文献
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58.
Lithium Doping to Enhance Thermoelectric Performance of MgAgSb with Weak Electron–Phonon Coupling
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Zihang Liu Yumei Wang Jun Mao Huiyuan Geng Jing Shuai Yuanxu Wang Ran He Wei Cai Jiehe Sui Zhifeng Ren 《Liver Transplantation》2016,6(7)
Despite the unfavorable band structure with twofold degeneracy at the valence band maximum, MgAgSb is still an excellent p‐type thermoelectric material for applications near room temperature. The intrinsically weak electron–phonon coupling, reflected by the low deformation potential Edef ≈ 6.3 eV, plays a crucial role in the relatively high power factor of MgAgSb. More importantly, Li is successfully doped into Mg site to tune the carrier concentration, leading to the resistivity reduction by a factor of 3 and a consequent increase in power factor by ≈30% at 300 K. Low lattice thermal conductivity can be simultaneously achieved by all‐scale hierarchical phonon scattering architecture including high density of dislocations and nanoscale stacking faults, nanoinclusions, and multiscale grain boundaries. Collectively, much higher average power factor ≈25 μW cm?1 K?2 with a high average ZT ≈ 1.1 from 300 to 548 K is achieved for 0.01 Li doping, which would result in a high output power density ≈1.56 W cm?2 and leg efficiency ≈9.2% by calculations assuming cold‐side temperature Tc = 323 K, hot‐side temperature Th = 548 K, and leg length = 2 mm. 相似文献
59.
Chang X Wu Q Wang S Wang R Yang Z Chen D Jiao X Mao Z Zhang Y 《Journal of biochemical and molecular toxicology》2012,26(2):60-70
The cloning, expression in vitro, and characterization of two aminopeptidase Ns (APN5s and APN2s) isolated from the midgut of Cry1Ac-resistant (R) and susceptible (S) strains of Plutella xylostella larvae are presented in this paper. The deduced amino acid sequences of APN5s included C-terminal GPI-modification sites, the gluzincin aminopeptidase motif GATEN, and three N-glycosylated sites; those of APN2s had no GPI-modification sites, had gluzincin aminopeptidase motif GAMEN, and had four N-glycosylated sites. O-glycosylated sites were not predicted for either APN. Because APN2R and APN2S cDNAs contained the same nucleotides, only full-length cDNAs encoding APN5R and APN5S were expressed in Trichoplusia ni cells. Far-Western blotting showed that the expressed receptor APN5 bound to the Cry1Ac toxin. An enzyme-specific activity experiment also showed that APN5 genes were expressed in T. ni cells. ELISA revealed no differences in the binding of expression proteins from the resistant and susceptible strain with Cry1Ac. 相似文献
60.
Axin and Frat1 interact with dvl and GSK, bridging Dvl to GSK in Wnt-mediated regulation of LEF-1. 总被引:21,自引:0,他引:21
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L Li H Yuan C D Weaver J Mao G H Farr rd D J Sussman J Jonkers D Kimelman D Wu 《The EMBO journal》1999,18(15):4233-4240