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Differential expression of adrenomedullin and resistin in 3T3-L1 adipocytes treated with tumor necrosis factor-alpha 总被引:2,自引:0,他引:2
Li Y Totsune K Takeda K Furuyama K Shibahara S Takahashi K 《European journal of endocrinology / European Federation of Endocrine Societies》2003,149(3):231-238
DESIGN: It has recently been shown that deficiency of adrenomedullin (AM), a potent vasodilator peptide, leads to insulin resistance. We studied expression of AM in NIH 3T3-L1 adipocytes and compared it with expression of resistin, an adipocyte-derived peptide hormone that is proposed to cause insulin resistance. Moreover, we studied the effects of tumor necrosis factor-alpha (TNF-alpha), a known mediator of insulin resistance, on the expression of AM and resistin in 3T3-L1 adipocytes. METHODS: 3T3-L1 cells were induced to differentiate to adipocytes by insulin, dexamethasone and 3-isobutyl-1-methylxanthine. Expression of AM mRNA and resistin mRNA was examined by Northern blot analysis. Immunoreactive AM in the medium was measured by RIA. RESULTS: AM mRNA was expressed in preadipocytes, but barely detectable in adipocytes. Immunoreactive AM was detected in the medium of both preadipocytes and adipocytes, with about 2.5 times higher levels found in preadipocytes. In contrast, resistin mRNA was expressed in adipocytes, whereas it was not detected in preadipocytes. Treatment with TNF-alpha increased AM expression in both adipocytes and preadipocytes, whereas it decreased resistin mRNA levels in adipocytes. CONCLUSIONS: The present study has shown that AM expression was down-regulated and resistin expression was up-regulated during adipocyte differentiation of 3T3-L1 cells. TNF-alpha acted as a potent negative regulator of resistin expression and a potent positive regulator of AM expression in adipocytes, raising the possibility that in addition to its known actions in causing insulin resistance, TNF-alpha may also have actions against insulin resistance through AM and resistin. 相似文献
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Liu F Fan HQ Qiu J Wang B Zhang M Gu N Zhang CM Fei L Pan XQ Guo M Chen RH Guo XR 《World journal of gastroenterology : WJG》2008,14(1):95-100
AIM: To confirm whether insulin regulates resistin expression and secretion during differentiation of 3T3-L1 preadipocytes and the relationship of resistin with insulin resistance both in vivo and in vitro. METHODS: Supernatant resistin was measured during differentiation of 3T3-L1 preadipocytes. L6 rat myoblasts and hepatoma cell line H4IIE were used to confirm the cellular function of resistin. Diet-induced obese rats were used as an insulin resistance model to study the relationship of resistin with insulin resistance. RESULTS: Resistin expression and secretion were enhanced during differentiation 3T3-L1 preadipocytes. This cellular differentiation stimulated resistin expression and secretion, but was suppressed by insulin. Resistin also induced insulin resistance in H4IIE hepatocytes and L6 myoblasts. In diet-induced obese rats, serum resistin levels were negatively correlated with insulin sensitivity, but not with serum insulin. CONCLUSION: Insulin can inhibit resistin expression and secretion in vitro, but insulin is not a major regulator of resistin in vivo. Fat tissue mass affects insulin sensitivity by altering the expression and secretion of resistin. 相似文献
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目的观察抵抗素结合多肽(RBP)对3T3-L1脂肪细胞分化、脂代谢及葡萄糖转运体4(GLUT-4)基因表达的影响。方法构建大鼠抵抗素真核表达载体并转染3T3-L1前体脂肪细胞,获得稳定表达抵抗素基因细胞株;采用台盼蓝排斥试验,确定理想的RBP干预浓度,于诱导细胞分化第0天加入培养液;采用油红O染色,观察脂肪细胞分化及脂质积聚情况;采用RT-PCR技术检测脂肪细胞分化标志基因及GluT-4基因表达变化;采用全自动生化仪比色法,检测脂肪细胞内TG和游离脂肪酸FFAs含量的变化。结果(1)RBP浓度10^-12mol/L时,脂肪细胞活细胞数比例较高,且细胞形态无明显改变。(2)RBP对正常脂肪细胞分化进程无明显影响,RBP虽未影响抵抗素稳定表达脂肪细胞内脂滴的出现时间,但细胞内脂滴的数目明显减少。(3)RBP对正常脂肪细胞分化标志基因及抵抗素稳定表达细胞分化早期标志基因Pref-1的表达无明显影响,但明显下调抵抗素稳定表达细胞分化中晚期标志基因C/EBPα和FAS的表达水平。(4)RBP对正常脂肪细胞内TG、FFAs含量无影响,但可显著降低抵抗素稳定表达脂肪细胞内的TG、FFAs含量。(5)RBP干预对正常脂肪细胞及抵抗素稳定表达脂肪细胞中GluT-4基因的表达水平均无显著影响。结论RBP对正常3T3-L1脂肪细胞的分化、脂代谢、GluT-4基因表达均无明显影响,但能有效拮抗抵抗素基因,显著促进3T3-L1脂肪细胞分化及脂代谢。 相似文献
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Xiao-Min Xin Mu-Xiao Zhong Gong-Li Yang Yao Peng Ya-Li Zhang Wei Zhu 《World journal of gastroenterology : WJG》2014,20(42):15727-15735
AIM: To investigate the effect of GW4064 on the expression of adipokines and their receptors during differentiation of 3T3-L1 preadipocytes and in HepG2 cells.METHODS: The mRNA expression of farnesoid X receptor (FXR), peroxisome proliferator-activated receptor-gamma 2 (PPAR-γ2), adiponectin, leptin, resistin, adiponectin receptor 1 (AdipoR1), adiponectin receptor 2 (AdipoR2), and the long isoform of leptin receptor (OB-Rb) and protein levels of adiponectin, leptin, and resistin were determined using fluorescent real-time PCR and enzyme linked immunosorbent assay, respectively, on days 0, 2, 4, 6, and 8 during the differentiation of 3T3-L1 preadipocytes exposed to GW4064. Moreover, mRNA expression of AdipoR2 and OB-Rb was also examined using fluorescent real-time PCR at 0, 12, 24, and 48 h in HepG2 cells treated with GW4064.RESULTS: The mRNA expression of FXR, PPAR-γ2, adiponectin, leptin, resistin, AdipoR1, AdipoR2, and OB-Rb and protein levels of adiponectin, leptin, and resistin increased along with differentiation of 3T3-L1 preadipocytes (P < 0.05 for all). The mRNA expression of FXR, PPAR-γ2, adiponectin, leptin, and AdipoR2 in 3T3-L1 preadipocytes, and AdipoR2 and OB-Rb in HepG2 cells was significantly increased after treatment with GW4064, when compared with the control group (P < 0.05 for all). A similar trend was observed for protein levels of adipokines (including adiponectin, leptin and resistin). However, the expression of resistin, AdipoR1, and OB-Rb in 3T3-L1 cells did not change after treatment with GW4064.CONCLUSION: The FXR agonist through regulating, at least partially, the expression of adipokines and their receptors could offer an innovative way for counteracting the progress of metabolic diseases such as nonalcoholic fatty liver disease. 相似文献
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目的 了解甘丙肽对脂肪组织及 3T3 L1细胞抵抗素表达的影响。方法 应用RT PCR、原位杂交的方法验证甘丙肽及其受体在大鼠脂肪组织及脂肪细胞中的表达。应用Northern印迹的方法观察甘丙肽对抵抗素表达的影响。结果 甘丙肽及其受体 1和 2在大鼠脂肪组织中均有表达 ,相对于甘丙肽受体 2 ,受体 1表达的丰度较高。给SD大鼠注入不同剂量甘丙肽 4h后 ,抵抗素基因表达下降。诱导成熟的脂肪细胞加入甘丙肽后 ,在 2h ,4h ,抵抗素的表达无明显的改变 ,但 2 4h可见抵抗素的表达受到抑制。结论 甘丙肽可以在体内及体外抑制抵抗素的表达 ,提示在大鼠脂肪组织中表达的甘丙肽可能在能量代谢及胰岛素抵抗中起到一定的作用 相似文献
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Rathod M Vangipuram SD Krishnan B Heydari AR Holland TC Dhurandhar NV 《International journal of obesity (2005)》2007,31(1):78-86
OBJECTIVE: Human adenovirus Ad-36 causes adiposity in animal models and shows association with human obesity. Ad-36 enhances differentiation of 3T3-L1 and human preadipocytes, without cell lysis, a characteristic that may contribute to its adipogenic effect observed in vivo. Ad-2, another human adenovirus is nonadipogenic in animals and in 3T3-L1 cells and shows no correlation with human obesity. The objective of this study was to determine the adipogenic roles of viral mRNA and DNA, which may explain the differential effects of Ad-36 and Ad-2 on preadipocyte differentiation. METHODS: This study determined the duration of selected Ad-36 gene expression in 3T3-L1 cells, and the effect on preadipocytes differentiation, when Ad-36 gene expression was attenuated by Cidofovir, an antiadenoviral agent. RESULTS: The results showed that Ad-36, but not Ad-2, expresses viral mRNA. Ad-36 gene expression peaked at 2-4 days postinoculation and very low levels persisted after day 7. Despite the viral mRNA expression, Ad-36 infection of 3T3-L1 cells was abortive as indicated by a progressive decrease in viral DNA quantity. Attenuation of Ad-36 mRNA expression by Cidofovir reduced the adipogenic effect of the virus. CONCLUSION: In conclusion, viral mRNA expression, although transient, is a prerequisite for enhancing differentiation of preadipocytes by Ad-36. Viral DNA replication was not required for the effect. This is the first evidence for the role of gene expression of an adipogenic human virus in enhancing preadipocytes differentiation. This study provides the basis for further understanding novel regulatory modulators of preadipocytes differentiation. 相似文献
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目的 探讨体外培养3T3-L1前脂肪细胞诱导分化过程中chemerin基因表达水平的变化与脂肪细胞分化、脂质积聚之间的关系.方法 应用3-异丁基-1-甲基黄嘌呤、胰岛紊、地塞米松联合方案诱导其分化为成熟的脂肪细胞,采用油红0染色观察脂肪细胞分化及脂质聚集情况,并应用RT-PCR和Western印迹技术检测chemerin基因表达的变化.结果 3T3 -L1脂肪细胞分化过程中,chemerin mRNA表达水平逐渐升高,分化至第6天达到较高水平且逐渐趋于稳定.利用Western印迹可观察到,随着脂肪细胞分化成熟.chemerin基因的蛋白表达水平逐渐增高.结论 chemerin mRNA及蛋白质在脂肪细胞分化成熟过程中表达水平升高,提示其很有可能参与了脂肪细胞分化和脂质聚集. 相似文献
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目的观察chemerin及其受体chemerinR基因在小鼠各脏器中的表达谱以及两者在3T3-L1脂肪细胞诱导分化过程中表达水平的变化。方法提取正常小鼠肝脏、脂肪、胃、脾脏、肾脏、心脏、骨骼肌等脏器组织中总RNA,采用半定量逆转录PCR技术检测其中chemerin及chemerinR基因水平;体外培养3T3-L1脂肪细胞,应用1-甲基-3-异丁基黄嘌呤(MIX)、地塞米松、胰岛素诱导其分化,采用适时PCR技术检测诱导分化不同时间脂肪细胞中chemerin及chemerinR基因的表达水平。结果 chemerin及chemerinR基因在小鼠体内广泛表达,以脂肪组织和肝脏为甚;二者低表达于3T3-L1前脂肪细胞中,并随前脂肪细胞诱导分化成熟表达水平呈逐渐上调趋势。结论 chemerin及其受体基因可能有利于脂肪细胞的分化成熟。 相似文献
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Kawashima J Tsuruzoe K Motoshima H Shirakami A Sakai K Hirashima Y Toyonaga T Araki E 《Diabetologia》2003,46(2):231-240
AIMS/HYPOTHESIS: Resistin is a peptide secreted by adipocytes and recognized as a hormone that could link obesity to insulin resistance. This study was designed to examine the effect and mechanism(s) of insulin on resistin expression in 3T3-L1 adipocytes. METHODS: Differentiated 3T3-L1 adipocytes were stimulated with insulin and resistin mRNA expression was examined by Northern blot analysis. In some experiments, the insulin signal was blocked by several chemical inhibitors or overexpression of a dominant negative form (Deltap85) of the p85 subunit of phosphatidylinositol 3-kinase (PI 3-kinase). RESULTS: Insulin treatment caused a reduction of resistin mRNA in time-dependent and dose-dependent manners in 3T3-L1 adipocytes. Pre-treatment with PD98059, an inhibitor of extracellular signal-regulated kinase 1/2 (ERK1/2) pathway, or SB203580, an inhibitor of p38 mitogen-activated protein-kinase (p38 MAP-kinase) pathway, did not influence insulin-induced reduction of resistin mRNA. Inhibition of PI 3-kinase by LY294002 or Deltap85 also failed to block insulin-induced reduction of resistin mRNA. Cycloheximide, a protein synthesis inhibitor, completely blocked insulin-induced reduction of resistin mRNA. Actinomycin D, a RNA synthesis inhibitor, also blocked insulin-induced reduction of resistin mRNA, and the decreasing rate of resistin mRNA in cells treated with insulin alone was faster than that with actinomycin D. CONCLUSION/INTERPRETATION: Insulin downregulates resistin mRNA via PI 3-kinase, ERK or p38 MAP-kinase independent pathways in 3T3-L1 adipocytes. The downregulation mechanism of resistin mRNA by insulin would be an indirect event through the synthesis of novel protein(s) that could accelerate the degradation of resistin mRNA. 相似文献
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目的 探讨microRNA(miRNA)-200c对3T3-L1前体脂肪细胞分化的影响.方法 利用实时PCR检测miRNA-200c在小鼠骨髓间充质干细胞(MSCs)向脂肪细胞分化过程及向骨细胞分化过程中的表达.通过将miRNA-200c类似物、miRNA-200c抑制剂转染至3T3-L1前体脂肪细胞,从而在细胞中增强或抑制miRNA-200c的表达,油红O染色检测转染后3T3-L1前体脂肪细胞诱导成熟后的脂滴形成情况.实时PCR检测转染后脂肪细胞特异性转录因子过氧化物酶体增殖物活化受体γ(PPARγ)和表征基因aP2在成脂过程中的表达变化.结果 实时PCR结果显示,在小鼠骨髓MSCs诱导成脂后miRNA-200c表达升高(t=24.709,P<0.01),而诱导成骨后,miRNA-200c表达下降(t=8.783,P<0.01).转染miRNA-200c类似物后,3T3-L1前体脂肪细胞中脂滴明显增多,PPARγ和aP2表达显著升高(t=7.674、9.657,P均<0.01);转染miRNA-200c抑制剂后,3T3-L1前体脂肪细胞中脂滴明显减少,PPARγ、aP2表达显著降低(t=9.483、6.419,P均<0.01).结论 miRNA-200c能够促进3T3-L1前体脂肪细胞向脂肪细胞分化. 相似文献
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GH is one of the major factors required for the differentiation of 3T3-F442A preadipocyte fibroblasts into adipocytes. An early event following the addition of GH to 3T3-F442A preadipocytes is induction of the expression of c-fos and c-jun. Although c-fos and c-jun expression has been observed in conjunction with growth factor-stimulated differentiation in several cell types, it is not clear whether protooncogene expression and differentiation are necessarily related. In this study the relationship between the induction of these protooncogenes and differentiation was evaluated by taking advantage of several cell lines that are related to 3T3-F442A cells but have varying GH requirements for differentiation. Adipose differentiation in the adipogenic cell lines 3T3-L1 and 3T3-GI-16 is known to be GH independent, requiring insulin or insulin-like growth factor-I. In both 3T3-L1 and 3T3-GI-16 preadipocytes, GH, nevertheless, induced the expression of mRNA for both protooncogenes. GH (2.2 nM) was more effective than insulin (1 microM) in inducing c-fos expression in these two adipogenic cell lines, suggesting that induction of the protooncogenes is not sufficient to induce adipogenesis. 3T3-C2 fibroblasts do not differentiate in response to any of the stimuli that convert 3T3-F442A fibroblasts to adipocytes. However, GH (2.2 nM) as well as calf serum induced the expression of c-fos and c-jun in 3T3-C2 cells. NIH-3T3 fibroblasts, which do not undergo differentiation, also showed induction of c-fos by GH. Thus, GH-induced expression of c-fos and c-jun occurs in nondifferentiating cells. Furthermore, in differentiated 3T3-F442A adipocytes, GH stimulated the expression of c-fos and c-jun as it does in the preadipocytes. Since GH elicits a variety of metabolic responses in 3T3-F442A adipocytes, the present findings raise the possibility that induction of c-fos and c-jun expression might be associated with multiple events in GH-stimulated 3T3-F442A adipocytes. The lack of requirement for GH in GH-independent and nondifferentiating cells compared to 3T3-F442A cells does not appear to reflect the lack of GH receptors, since expression of mRNA for the GH receptor was evident in all of the cell types tested and, thus, corresponds with the ability of GH to induce protooncogene expression. Although GH-induced c-fos expression was relatively invariant, since it was evident in all of the cell types studied, this response could clearly be regulated, since it was attenuated by prior exposure to GH or serum in 3T3-F442A preadipocytes.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
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Adipose tissue contains macrophages whose state of activation is regulated as obesity develops. Macrophage-secreted factors influence critical processes involved in adipose tissue homeostasis, including preadipocyte proliferation and differentiation into adipocytes. Macrophage-conditioned medium (MacCM) from J774A.1 macrophages protects 3T3-L1 preadipocytes from apoptosis through platelet-derived growth factor (PDGF) signaling. Here, we investigated the effect of macrophage activation on MacCM-dependent preadipocyte survival. MacCM was prepared following activation of either J774A.1 macrophages with lipopolysaccharide (LPS) or human primary monocyte-derived macrophages (MD-macrophages) with LPS or interleukin 4 (IL4). 3T3-L1 and human primary preadipocytes were induced to undergo apoptosis in MacCM, and apoptosis was quantified by cell enumeration or Hoechst nuclear staining. Preadipocyte PDGF signaling was assessed by immunoblot analysis of phosphorylated PDGF receptor, Akt, and ERK1/2. Pro-inflammatory activation of J774A.1 macrophages with LPS inhibited the pro-survival activity of MacCM on 3T3-L1 preadipocytes, despite intact PDGF signaling. Upregulation of macrophage tumor necrosis factor a (TNFα) expression occurred in response to LPS, and TNFα was demonstrated to be responsible for the inability of LPS-J774A.1-MacCM to inhibit preadipocyte apoptosis. Furthermore, MacCM from human MD-macrophages (MD-MacCM) inhibited apoptosis of primary human preadipocytes. MD-MacCM from LPS-treated macrophages, but not IL4-treated anti-inflammatory macrophages, was unable to protect human preadipocytes from cell death. In both murine cell lines and human primary cells, pro-inflammatory activation of macrophages inhibits their pro-survival activity, favoring preadipocyte death. These findings may be relevant to preadipocyte fate and adipose tissue remodeling in obesity. 相似文献
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Aims/hypothesis In obesity, a limited adipogenic capacity may promote adipocyte hypertrophy and increase the risk of insulin resistance and type 2 diabetes. Recent data indicate that macrophages reside within adipose tissue in obese rodents and humans. We hypothesised that secreted macrophage factors may inhibit adipogenesis.Materials and methods Conditioned media from cultured murine J774 or human THP-1 macrophages were collected, and added to either murine 3T3-L1 preadipocytes or human abdominal stromal preadipocytes from subcutaneous or omental fat depots.Results Macrophage-conditioned medium (MacCM) strongly inhibited 3T3-L1 adipogenesis. Dose–response studies with J774-MacCM revealed that 80 and 100% of J774-MacCM completely suppressed triacylglycerol accumulation as well as the induction of fatty acid synthase, peroxisome proliferator-activated receptor γ, CCAAT/enhancer binding protein α, and adiponectin. Similar inhibitory effects on 3T3-L1 preadipocytes were observed with THP-1-MacCM. Differentiation of human abdominal subcutaneous stromal preadipocytes was moderately reduced (subcutaneous>omental) by J744-MacCM. In contrast, the differentiation of both subcutaneous and omental stromal preadipocytes was completely inhibited by THP-1-MacCM, as determined on the basis of morphology and triacylglycerol accumulation, as well as fatty acid synthase and adiponectin protein expression.Conclusions/interpretation Secreted macrophage products inhibit the differentiation of 3T3-L1 preadipocytes as well as human abdominal stromal preadipocytes. 相似文献
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目的探讨胰升血糖素样肽1(GLP-1)对3T3-L1前脂肪细胞增殖及分化的影响。方法在3T3-L1前脂肪细胞增殖和分化的不同阶段添加不同浓度梯度的GLP-1(7—36),使用XTT比色法测定细胞增殖情况,油红O脂肪染色、异丙醇萃取法评价细胞分化情况,RT-PCR法测定不同分化阶段PPAR-ymRNA表达水平。结果高浓度GLP-1(10^-9~10^-7mool/L)能够减弱3T3-L1前脂肪细胞的增殖能力;GLP-1在10^-11~10^-8mmoL/浓度梯度均存在抑制3T3-L1前脂肪细胞向脂肪细胞分化的作用,但对分化过程中PPARymRNA的表达水平均未见显著影响。结论本研究发现GLP-1能够抑制3T3-L1前脂肪细胞增殖及分化,提示脂肪细胞可能也是GLP-1减轻体重作用的潜在靶点。 相似文献
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