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The mechanism for how fucoxanthin (FX) suppressed adipose accumulation is unclear. We aim to investigate the effects of FX on metabolic rate and expressions of genes related to thermogenesis, mitochondria biogenesis and homeostasis. Using a 2 × 2 factorial design, four groups of mice were respectively fed a high sucrose (50% sucrose) or a high-fat diet (23% butter + 7% soybean oil) supplemented with or without 0.2% FX. FX significantly increased oxygen consumption and carbon dioxide production and reduced white adipose tissue (WAT) mass. The mRNA expressions of peroxisome proliferator-activated receptor (PPAR) γ coactivator-1α (PGC-1α), cell death-inducing DFFA-like effecter a (CIDEA), PPARα, PPARγ, estrogen-related receptor α (ERRα), β3-adrenergic receptor (β3-AR) and deiodinase 2 (Dio2) were significantly upregulated in inguinal WAT (iWAT) and epididymal WAT (eWAT) by FX. Mitochondrial biogenic genes, nuclear respiratory factor 1 (NRF1) and NRF2, were increased in eWAT by FX. Noticeably, FX upregulated genes of mitochondrial fusion, mitofusin 1 (Mfn1), Mfn2 and optic atrophy 1 (OPA1), but not mitochondrial fission, Fission 1, in both iWAT and eWAT. In conclusion, dietary FX enhanced the metabolic rate and lowered adipose mass irrespective of the diet. These were associated with upregulated genes of the PGC-1α network and mitochondrial fusion in eWAT and iWAT. 相似文献
74.
Carotenoids are a class of diverse pigments with important biological roles such as light capture and antioxidative activities. Many novel carotenoids have been isolated from marine organisms to date and have shown various utilizations as nutraceuticals and pharmaceuticals. In this review, we summarize the pathways and enzymes of carotenoid synthesis and discuss various modifications of marine carotenoids. The advances in metabolic engineering and synthetic biology for carotenoid production are also reviewed, in hopes that this review will promote the exploration of marine carotenoid for their utilizations. 相似文献
75.
《植物养料与土壤学杂志》2017,180(5):602-613
Silver nanoparticles (AgNP) are used in a broad range of consumer products and industrial applications. During the regular product life cycle and disposal, AgNP are continuously released into the environment. Hence, the aim of this study was to investigate the potential ecotoxicological effects of AgNP exposure on amoebae. The Acanthamoeba castellanii ATCC 30234 strain and environmental isolate Acanthamoeba strain C5/2, which are both affiliated with genotype T4, were chosen as representatives of ecologically important soil protozoan organisms. The amoebae were exposed to citrate‐stabilized AgNP (30 and 70 nm in size) for 24 h and 96 h at concentrations ranging from 600 µg L−1 to 20 mg L−1. A newly adopted cell culture based microscopic assay was applied to assess the adherence ability of the amoeba trophozoites. The general metabolic activity of Acanthamoeba was determined to be a second independent endpoint by means of intracellular reduction of the redox dye AlamarBlue®. The fate of AgNP within the amoebae and test solutions was visualized by light‐ and transmission electron microscopy (TEM). Both Acanthamoeba strains showed a significant dose‐dependent decrease of adherence ability (p < 0.04) and metabolic activity (p < 0.01) after 96 h of AgNP exposure. The environmental Acanthamoeba strain C5/2 lost both its adherence ability and metabolic activity at lower AgNP concentrations than the type strain, indicating a higher sensitivity to ionic silver. This was confirmed by the application of AgNO3, provoking a higher effect level in strain C5/2. AgNP was visualized intracellularly by transmission electron microscopy within the cytoplasm of Acanthamoeba . This is the first report to show the ecotoxicological effects of short‐term AgNP exposure on the soil protist Acanthamoeba , causing both changes in the adherence ability and metabolic activity of this amoeba. This combined approach may be a powerful tool in the future for predicting potential harmful ecotoxicological effects of AgNP exposure using soil protozoans. 相似文献
76.
M. Duru 《Journal of Agronomy and Crop Science》2008,194(5):401-412
For management purposes, models of lamina digestibility (DW) that are thermal time driven (Tsum) fail to account for plant nitrogen status (0 < Ni < 1) and defoliation intensity (residual sheath height: Sr). The objective of this paper was to enrich them using a functional processed-based model, which assumes that the decline in DW over time depends on the metabolic : structural tissue ratio and plant ageing. An experiment combining two N fertilizer rates and two defoliation regimes (differences in Sr) for two spring and two summer regrowth was done to analyse DW of laminae (youngest fully expanded) and tiller (whole green lamina) levels. For laminae, we show that both processes contribute to explain the decline in DW at a rate that depends on Ni but not on Sr. For tillers, consistent results were found justifying the use of a simple model: DW = f(+Ni; −Ni × Tsum; −Sr). Two different databases (from experiment and commercial farms) were used for validation: RMSD varied from 35 to 49 g kg−1. The process-based model strengthened the empirical model and improved the comprehensiveness of how management practices change DW. We used both models to create applications for reasoning yield in function of herbage mass in complement than in function of time. 相似文献
77.
Miriam Altstein Orna Ben-Aziz Irit Schefler Irina Zeltser Chaim Gilon 《Crop Protection》2000,19(8-10):547-555
The development of a new approach for the generation of a novel type of putative insect control agents based on backbone cyclic peptidomimetic antagonists of insect-neuropeptides is reported. The approach, termed the backbone cyclic neuropetide based on autogonist (BBC-NBA) was applied to the insect pyrokinin/pheromone biosynthesis activating neuropeptide (PBAN) family as a model, and led to the discovery of a potent linear lead antagonist and several highly potent, metabolically stable BBC peptidomimetic antagonists, devoid of agonistic activity, which inhibited in vivo PBAN-mediated activities in moths. 相似文献
78.
A new gene is reported which functions as a master gene for synthesis of the pigments determining cotyledon colour in lentil.
This gene is different from the two earlier reported genes which are responsible for synthesis of yellow (gene Y) and brown (gene B) pigments. Double recessive homozygous condition of these two genes results into loss of both pigments and, consequently,
produces light green cotyledons. The new gene, in contrast, produces dark green cotyledons in recessive condition irrespective
of the dominance or recessive state of the Y and B genes. It is hypothesized that the new gene for dark green cotyledon colour (Dg) acts at an earlier stage in the biosynthesis of the two cotyledon-specific pigments, which are derived from a common precursor,
whose synthesis is blocked when Dg mutates to its recessive condition.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
79.
花生素(TCBA)是一种新型的植物生长调节剂。经多年在花生、大豆等作物上进行叶面喷施的小区试验和生产示范试验,都表现出明显的增产作用,尤其对花生的增产效果更显著,增产幅度可达15%以上。增产原因主要是能调节作物营养生长与生殖的关系,使之协调发展,同时能捉高作物叶片中叶绿素的含量和光合效率,并能促进光合产物向产品器官中运输。 相似文献
80.
大尾寒羊妊娠期蛋白质维持需要量及代谢规律的研究 总被引:1,自引:0,他引:1
选用大尾寒羊妊娠及空怀母羊各6只,进行氮平衡试验。结果表明,大尾寒羊妊娠并不能导致其采食量显著提高;妊娠大尾寒羊与空怀母羊相比,蛋白质的沉积效率显著提高(P<0.05);大尾寒羊妊娠期可消化粗蛋白的维持需要量(RDCPm)可以由下述公式求得:RDCPm=2.43W0.75(g/d)式中:W0.75为代谢体重(kg) 相似文献