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A preadipocyte primary cell culture was established to gain knowledge about adipose tissue development in gilthead sea bream (Sparus aurata), one of the most extensively produced marine aquaculture species in the Mediterranean. The preadipocytes obtained from the stromal-vascular cell fraction of adipose tissue proliferated in culture, reaching confluence around day 8. At that time, the addition of an adipogenic medium promoted differentiation of the cells into mature adipocytes, which showed an enlarged cytoplasm filled with lipid droplets. First, cell proliferation and differentiation were analyzed under control and adipogenic conditions during culture development. Next, the effects of insulin, GH, and IGF-I on cell proliferation were evaluated at day 8. All peptides significantly stimulated proliferation of the cells after 48 h of incubation (P < 0.002 for GH and IGF-I and P < 0.05 for insulin), despite no differences were observed between the different doses tested. Subsequently, the effects of insulin and IGF-I maintaining differentiation when added to growth medium were studied at day 11, after 3 d of induction with adipogenic medium. The results showed that IGF-I is more potent than insulin enhancing differentiation (P < 0.01 for IGF-I compared with the control). In summary, a primary culture of gilthead sea bream preadipocytes has been characterized and the effects of several regulators of growth and development have been evaluated. This cellular system can be a good model to study the process of adipogenesis in fish, which may help improve the quality of the product in aquaculture.  相似文献   

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The extracellular matrix (ECM) and specific ECM components can have a major influence on cell growth, development, and phenotype. The influence of the ECM and ECM components on adipogenesis in vivo and in vitro will be reviewed in this paper. Engelbreth-Holm-Swarm substratum and laminin per se markedly increased attachment, spreading, and hypertrophy of preadipocytes in serum-free primary cultures of porcine adipose tissue stromal-vascular cells. Furthermore, primary cultures of stromal-vascular cells showed that preadipocytes express ECM components after preadipocyte recruitment. Staining for plant lectins, type IV collagen, and laminin in fetal pig adipose tissue demonstrates that adipocyte reactivity for laminin was strong throughout fetal development and was similar for developing adipocytes and vasculature. However, lectin binding and type IV collagen reactivity of blood vessels preceded that for adipocytes. Therefore, these studies indicated that the ECM and in particular laminin may play a critical role in morphological aspects of preadipocyte development. Specific inhibitors and modulators of collagen synthesis have been used to evaluate the role of collagens in the differentiation of bovine intramuscular preadipocytes (BIP) and other preadipocyte cell lines. Triglyceride accretion of BIP cells was inhibited by a general inhibitor of collagen biosynthesis, whereas specific inhibitors or modulators of type IV collagen inhibited 3T3-L1 cell differentiation. Further study revealed that compared with collagens types I to IV, type V and VI collagens have an important and active role in BIP adipogenesis. The growth of intramuscular bovine adipose tissue may be dependent on collagen newly synthesized and organized by the adipocytes per se. The role of extracellular or ECM proteolysis in regulating adipogenesis also will be reviewed in this paper. Many members of the matrix metalloproteinase (MMP) family are expressed by adipocytes, and specific inhibition of MMP-9 greatly reduces adipogenesis in vitro. Possibly, MMP and other proteases regulate turnover of key adipocyte ECM proteins that are involved in the regulation of preadipocyte proliferation and differentiation.  相似文献   

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Intramuscular fat (IMF) content plays an important role in meat quality. Triglyceride (TG) metabolism in intramuscular adipocytes is strongly associated with the intramuscular fat deposition. To better understand the mechanisms leading to IMF deposition we compared the expression levels of genes related to preadipocyte differentiation and lipogenesis in the intramuscular preadipocytes isolated from the longissimus muscle of Wujin and Landrace pigs. The results showed that the intramuscular preadipocytes could differentiate into mature adipocytes in vitro. Triglyceride content in adipocytes isolated from Wujin pigs was higher than Landrace pigs during the middle and later phases of preadipocyte differentiation. The expression levels of genes related to preadipocyte differentiation such as PPARG and CEBPA showed differential expression between Wujin and Landrace porcine adipocytes during the early stage of differentiation. The expression levels of lipogenic genes such as FASN and SREBF1 were significantly higher in Wujin porcine intramuscular preadipocytes than in Landrace intramuscular preadipocytes at the middle and the later stages of differentiation. This suggests that preadipocyte differentiation and lipogenesis exhibited breed-related scheduling.  相似文献   

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Fatty acid transport protein 1 (FATP1) plays an important role in the fatty acid transmembrane transport and fat deposition. However, its role in porcine intramuscular preadipocytes proliferation and differentiation remain poorly understood. Here, we examined the effects of pFATP1 on porcine intramuscular preadipocytes proliferation and differentiation. Overexpression of pFATP1 in porcine intramuscular preadipocytes significantly promoted the proliferation of porcine intramuscular preadipocytes, and also significantly upregulated the expressions of peroxisome proliferator‐activated receptor γ, CCAAT enhancer binding protein α, lipoprotein lipase, fatty acid synthetase and perilipin 1. Moreover, overexpression of pFATP1 in porcine intramuscular preadipocytes significantly increased fat accumulation and downregulated β‐catenin protein expression. Overall, our results indicated that pFATP1 played an important role in porcine intramuscular preadipocytes proliferation and differentiation, and it might promote adipogenesis in porcine intramuscular preadipocytes by repressing Wnt/β‐catenin signaling pathway.  相似文献   

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The purpose of this study was to detect differential expression of genes related to adipocyte differentiation in pigs by suppression subtractive hybridization. Adipocytes and stromal vascular cells (a fraction containing preadipocytes) from pig adipose tissue were isolated for mRNA extraction. The cDNA from preadipocytes was subtracted from the cDNA from adipocytes. The subtracted gene fragments were cloned into pGEM-T Easy TA cloning vector. We selected 384 clones for gene sequence determination and for further analysis. These genes were subjected to a differential screening procedure to confirm the differential expression of genes between the 2 cell types. We found that at least 36 genes were highly expressed in the adipocytes compared with preadipocytes. Among these, 6 genes including 2 novel genes with the greatest differences were selected and confirmed by Northern analysis. We found that angiotensin I-converting enzyme (ACE), ataxia-telangiectasia mutated protein (ATM), calpain 1, and stearoyl coenzyme A desaturase 1 (SCD1) were highly expressed in adipocytes compared with preadipocytes (P < 0.05). The relative mRNA abundance of ACE, ATM, calpain 1, SCD1, and 2 novel genes discovered in the current study was increased at the later stages of adipocyte differentiation (P < 0.05). The results confirmed that the genes involved in lipid metabolism and adipocyte differentiation were highly expressed in porcine adipocytes. However, further investigation is needed to demonstrate specific functions of the novel genes discovered in the current study.  相似文献   

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We hypothesized that both adiponectin and leptin affect the growth of porcine skeletal muscle cells, with fatty acids acting as modifiers in adipokine action and that both adipokines influence the gene expression of their receptors. Therefore, the objective of this study was to investigate the effects of recombinant adiponectin and leptin on cell number (DNA) and DNA synthesis rate with and without oleic acid supplementation, on cell death, and on key intracellular signaling molecules of proliferating porcine myoblasts in vitro. Moreover, the mRNA expression of genes encoding for the leptin and adiponectin receptors (LEPR, ADIPOR1, ADIPOR2) as affected by leptin or adiponectin was examined. Recombinant porcine adiponectin (40 μg/mL) and leptin (20 ng/mL) increased DNA synthesis rate, measured as [3H]-thymidine incorporation (P < 0.01), reduced cell viability in terms of lactate dehydrogenase release (P < 0.05), or lowered DNA content after 24 h (P < 0.05). In adiponectin-treated cultures, oleic acid supplementation increased DNA synthesis rate and reduced cell number in a dose-dependent manner (P < 0.05). Both adiponectin (P = 0.07) and leptin (P < 0.05) induced a transient activation of p44/42 mitogen-activated protein kinase (MAPK) after 15 min, followed by decreases after 60 and 180 min (P < 0.05). Adiponectin tended to increase c-fos activation (P = 0.08) and decreased p53 activation at 180 min (P = 0.03). Both adiponectin and leptin down-regulated the abundance of ADIPOR2 mRNA and, transiently, of LEPR mRNA (P < 0.05). In conclusion, adiponectin and leptin may adversely affect the growth of porcine myoblasts, which is related to p44/42 MAPK signaling and associated with changes in ligand receptor gene expression.  相似文献   

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Peroxisome proliferator-activated receptor gamma (PPARgamma) plays a critical role in regulating adipogenesis. The expression of peroxisome proliferator-activated receptor delta (PPARdelta) precedes that of PPARgamma during adipocyte differentiation in rodents. The current experiment was designed to study the function of porcine PPARdelta and the interaction of PPARdelta and PPARgamma in adipocyte differentiation. Inhibition of myogenesis was observed in mouse myoblasts expressing porcine PPARdelta, similar to myoblasts expressing PPARgamma. Treatment of myoblasts expressing PPARdelta with ligands for both PPARdelta and PPARgamma enhanced lipogenesis and adipogenesis to a greater extent than treatment with a PPARgamma ligand alone, suggesting that both genes were involved in regulating lipogenesis and adipogenesis. The ability to transdifferentiate myoblasts into adipocytes was decreased in myoblasts coexpressing PPARdelta with either wild type or mutated PPARgamma (Ser 112 was mutated to Ala; the mutated PPARgamma is more active than the wild type) compared with myoblasts expressing PPARgamma alone. Adipocyte differentiation in myoblasts coexpressing PPARdelta and mutated PPARgamma was greater than in myoblasts coexpressing PPARdelta and wild type PPARgamma, confirming that Ser 112 is important for the function of PPARgamma. Taken together, our results demonstrate that overexpression of PPARdelta inhibits myotube formation and also enhances adipocyte differentiation. However, the complexity and interaction of PPARdelta and PPARgamma in adipogenesis are not clearly understood.  相似文献   

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Different vaccination strategies against Mycoplasma hyopneumoniae have been adopted worldwide. Reports from the field indicate varying levels of protection among currently available vaccines. The goal of the present study was to compare the efficacies of three widespread commercial vaccination strategies against M. hyopneumoniae under field conditions. 20 farms were included. 14 farms used different single dose vaccines (vaccine 1 [V1], 8 herds; vaccine 2 [V2], 6 herds); another 6 farms (V3) used a two dose vaccination strategy. Gross lesions of 854 lungs and histopathology from 140 lungs were quantified, and a quantitative PCR was applied to detect M. hyopneumoniae and porcine circovirus 2 (PCV2) DNA in lung tissue (n = 140). In addition, porcine reproductive and respiratory disease virus (PRRSV), swine influenza virus (SIV), Actinobacillus pleuropneumoniae, Haemophilus parasuis and Pasteurella multocida were tested by qualitative PCR. 53% of lungs were positive for M. hyopneumoniae. 55.9% of lungs showed macroscopic enzootic pneumonia (EP)-like lesions. Lung lesion scores (P < 0.001) and M. hyopneumoniae-loads (P < 0.008) differed significantly among the vaccination groups, with the most severe cases and highest amounts occurring in V1. Histological alterations differed (P < 0.001) between V1 and V3. Lung lesion scores and histopathological changes were significantly correlated, with prevalence and load of M. hyopneumoniae indicating that the applied diagnostic tools are valuable in confirming the prevalence and severity of M. hyopneumoniae infections. Comparing different vaccination strategies against M. hyopneumoniae indicates varying levels of protection. M. hyopneumoniae is still a major problem despite the widely applied vaccination.  相似文献   

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1,25(OH)2D3是维生素D的主要活性形式,影响人和动物脂肪形成,为探究其在猪脂肪细胞增殖分化中的作用,试验从3~5日龄仔猪皮下脂肪组织分离培养前体脂肪细胞,并以浓度为0、0.1、1、10、100和1 000 nmol/L的1,25(OH)2D3分别处理,在培养的0、1、2、4、6、8和10 d采用MTT比色法检测细胞增殖活性;在诱导分化后0、1、2、4、6、8和10 d,以油红O染色提取法和实时荧光定量PCR检测细胞成脂分化及分化标志基因过氧化物酶体增殖物激活受体γ(PPARγ)和脂肪酸合成酶(FAS)表达。结果显示,0.1和1 nmol/L 1,25(OH)2D3显著促进猪前体脂肪细胞增殖(P<0.05),而浓度为10~100 nmol/L时则抑制细胞增殖(P<0.05);0.1和1 nmol/L 1,25(OH)2D3显著抑制猪前体脂肪细胞分化(P<0.05),降低PPARγ和FAS mRNA表达水平(P<0.05),但在浓度为10和100 nmol/L时,显著促进猪前体脂肪细胞分化(P<0.05),上调PPARγ和FAS mRNA表达(P<0.05);浓度达1 000 nmol/L时,可能对细胞有毒性作用。综合以上结果,低浓度1,25(OH)2D3促进猪前体脂肪细胞增殖,而通过下调PPARγ表达抑制分化;高浓度1,25(OH)2D3抑制猪前体脂肪细胞增殖,通过上调PPARγ表达促进分化。1,25(OH)2D3对猪前体脂肪细胞增殖和分化具有双向作用。  相似文献   

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为阐明小尾寒羊HOXC8 DNA甲基化程度在前体脂肪细胞分化过程中的作用,本研究以小尾寒羊皮下前体脂肪细胞为实验材料,利用生物信息学软件和亚硫酸氢盐测序(Bisulfite Sequencing PCR,BSP)分析HOXC8启动子区和第1外显子区序列的CpG岛和甲基化水平;采用qPCR技术检测在绵羊前体脂肪细胞分化过程中HOXC8的表达水平。结果显示,HOXC8启动子区和第1外显子区各存在1个CpG岛;HOXC8mRNA的表达量在绵羊前体脂肪细胞分化前极显著高于分化后;在绵羊前体脂肪细胞分化第0天与第2天,HOXC8启动子区甲基化水平差异不显著,第1外显子区甲基化水平差异显著,且HOXC8第1外显子区甲基化水平均极显著高于启动子区(P<0.001);对HOXC8第1外显子区甲基化水平与其表达水平进行线性回归分析可知,二者呈高度正相关(r=0.994,P<0.0001)。HOXC8可能主要在绵羊前体脂肪细胞分化前发挥作用,在分化过程中HOXC8在转录水平的表达受第1外显子区甲基化的正调控。  相似文献   

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To study the impact of maternal l-arginine supplementation during early gestation on skeletal muscle formation in the offspring, gilts were fed 3 kg of a standard diet (control group, n=10) or standard diet and additionally 26 g/d l-arginine from d 14 to 28 of gestation (arginine group, n=10). The gilts were sacrificed at d 75 of gestation. From each litter the lightest, the heaviest, and one medium-weight foetus per sex were selected and three different muscle samples were collected. In the longissimus dorsi muscle of all foetuses (n=99) biochemical properties were assessed. In the same muscle of a subset of the lightest and heaviest female foetuses (n=28), mRNA expression of selected genes involved in myogenesis were measured. In all three muscles, myosin heavy chain (MyHC) expression analyses (n=99) were performed. The protein/DNA ratio tended to be lower (P=0.08) in the offspring of the arginine group. Treatment×sex interactions revealed lower creatine kinase activity (P<0.05) and protein concentration (P=0.07) in female's of the arginine group. The MYF5 mRNA expression was lower (P<0.01) in the lightest, whereas IGF2 and IGFBP5 expressions (P<0.001) were lower in the heaviest females of the arginine group. The proportion of MyHC mRNA expression revealed an increase in the embryonic isoform (P=0.05) and a decrease by tendency in the Slow/I and IIx isoforms (P<0.10) in response to arginine supplementation. The results suggest that arginine supplementation during early gestation stimulates myogenic proliferation and delays muscular differentiation at d 75 of gestation.  相似文献   

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以体外培养1日龄猪皮下前体脂肪细胞为研究对象,通过脂质体LipofectamineTM2000介导小窝蛋白-1(Caveolin-1,CAV1)过表达载体pEGFP-N1-CAV1及CAV1的干扰片段siRNA-CAV1分别转染猪皮下前体脂肪细胞,采用RT-PCR定量分析转染后24、48、72、96h的CAV1mRNA表达量以及转染后72h脂肪细胞分化相关基因的mRNA表达量;其后又进行了CAV1过表达或干扰且诱导分化后甘油三脂含量以及脂肪细胞分化相关基因的mRNA表达量测定。结果显示,过表达CAV1基因上调前体脂肪细胞分化相关基因PPARγ、C/EBPβ、AP2、GPDH的表达量,干扰CAV1基因下调C/EBPβ、PPARγ、AP2、LPL、VLDLR的表达量;诱导分化后干扰组C/EBPβ、LPL、VLDLR的表达量仍显著降低,而甘油三脂含量检测结果说明过表达CAV1基因能促进脂肪细胞分化,提示CAV1可能通过C/EBPβ、LPL、VLDLR等基因影响猪前体脂肪细胞分化。  相似文献   

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研究脂肪生成的机理及其调控过程对于防治动物肥胖引起的相关疾病、改善肉品风味和质量以及畜牧生产效率具有重要意义。脂肪细胞起源于多能性骨髓间充质干细胞(MSCs),接受细胞外刺激因子后迅速引起早期脂肪调节因子、C/EBPβ和C/EBPδ的表达,并传递信息至PPARγ和C/EBPα等转录因子,促进细胞的分化和脂滴形成。在此过程中,众多转录因子和细胞周期蛋白参与前体脂肪细胞到脂肪细胞的分化与成脂过程。植物来源的多种天然产物,如多酚类、生物碱、萜类、醌类化合物在脂肪细胞分化和抑制脂肪生成过程中发挥重要的调控作用,对这些天然化合物的深入和成药研究有望成为具有抑制细胞内脂滴聚集的潜在药物。  相似文献   

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This experiment was conducted to evaluate in vitro effects of equine fecal inocula fermentative capacity on 9 fibrous forages in the presence of Saccharomyces cerevisiae. The fibrous feeds were corn stover (Zea mays), oat straw (Avena sativa), sugarcane bagasse and leaves (Saccharum officinarum), llanero grass leaves (Andropogon gayanus), Taiwan grass leaves (Pennisetum purpureum), sorghum straw (Sorghum vulgare), and steria grass leaves (Cynodon plectostachyus). Fibrous feed samples were incubated with several doses of S. cerevisiae; 0 (control), 1.25 (low), 2.5 (medium) and 5 (high) mg/g dry matter (DM) of a commercial yeast product containing 1 × 1010/g. Fecal inoculum was collected from 4 adult horses were fed on an amount of commercial concentrate and oat hay ad libitum. Gas production (GP) was recorded at 2, 4, 6, 8, 10, 12, 24, and 48 hours post inoculation. An interaction occurred between feeds and yeast dose for fecal pH (P < .01), asymptotic GP (b, ml/g DM); rate of GP (c, /hr); initial delay before GP began (L, hours), GP at 4 hours and 48 hours (P < .01), and GP at 8 hours (P < .01) and at 24 hours (P < .01). Differences in fecal fermentation capacity between the tropical and template grass (P < .05) occurred for fecal pH, c, and GP during first 12 hours, whereas differences occurred (P < .05) between the agriculture byproducts and the grasses for fecal pH, b, and GP from 8 to 48 hours. Fermentation capacity between straws versus not straws (P < .05) differed for fecal pH, b, and GP after 12 hours between straws versus not straws. Addition of S. cerevisiae to Z. mays stover reduced (P < .01) fecal pH and the c fraction with a higher (P < .01) b fraction versus the other feeds. From 4 to 24 hours, S. officinarum bagasse improved GP to the highest values versusS. officinarum leaves. After 24 hours, Z. mays stover had the highest GP, whereas C. plectostachyus leaves had the lowest. There were no differences among the yeast doses for all measured parameters with the exception of L values (linear effect; P < .01). The Z. mays stover had the highest nutritive compared to the other fibrous feeds. However, addition of S. cerevisiae at 2.5 to 5.0 g/kg DM improved fecal fermentation capacity of low-quality forages.  相似文献   

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