小鼠前脂肪细胞3T3-L1培养与四联诱导分化方法的探讨

摘要： 目的 改进小鼠前脂肪细胞 3T3-L1 的培养并诱导分化为成熟脂肪细胞的方法。方法 使用含有 10％胎牛血清 （FBS） 的高糖型 DMEM 液体培养基常规培养小鼠前脂肪细胞, 2~3 d 换液 1 次。细胞按诱导分化方式的不同分为三联诱导组和四联诱导组。三联诱导组诱导分化培养基Ⅰ成分为常规培养基基础上加用人胰岛素 10 mg/L, 1- 甲基-3-异丁基黄嘌呤 （IBMX）0.5 mmol/L, 地塞米松 （DEX） 1.0 μmol/L; 四联诱导组诱导分化培养基Ⅰ的成分为在三联诱导组基础上加入吲哚美辛 0.1 mmol/L。2 组均诱导分化培养基Ⅰ培养 2 d, 连续诱导 2 次后换用诱导分化培养基Ⅱ, 成分为： 高糖型 DMEM 培养基含 10 %胎牛血清、 100 U/mL 青霉素和 100 mg/L 链霉素混合液, 人胰岛素 10 mg/ L。培养 2 d, 连续诱导 2 次。倒置显微镜和油红 O 染色观察诱导前及诱导后 2 组细胞的形态变化。结果 小鼠前脂肪细胞 3T3-L1 状态良好, 呈现铺路石状生长, 均匀布满培养瓶底, 2 d 传代 1 次。四联诱导组诱导分化结果优于三联诱导组。三联诱导剂诱导前脂肪细胞后, 细胞形态并未发生明显变化。四联诱导剂诱导前脂肪细胞后, 可达到 90％以上的成熟脂肪细胞。成熟的脂肪细胞呈圆形, 有大量脂滴聚集, 油红 O 染色显现橘红色。结论 在三联诱导基础上加入吲哚美辛的四联诱导法可以更好地促进脂肪前体细胞分化。     

太子参提取物对3T3-L1前脂肪细胞分化的影响

目的 探索太子参提取物对3 T3-L1前脂肪细胞分化的影响.方法 采用超声提取法获得太子参乙醇提取物,再分别用石油醚、乙酸乙酯、水饱和正丁醇进行连续萃取,用得到的太子参各溶剂萃取层作用于3 T3-L1前脂肪细胞分化模型,以罗格列酮为阳性对照药,并通过油红O染色观察其对前脂肪细胞分化过程的影响.结果 太子参乙醇提取物及各极性溶剂萃取层在0.4μg·mL-1和0.8μg·mL-1两个浓度下均能在一定程度上促进前脂肪细胞的分化过程,而且乙酸乙酯萃取层活性最强.结论 太子参乙酸乙酯萃取层具有较好的促进3 T3-L1前脂肪细胞分化的活性.     

中药对3T3-L1前脂肪细胞分化、增殖和凋亡影响的研究进展

3T3-L1前脂肪细胞从17—19日龄小鼠胚胎Swiss3T3细胞中分离获得,其具有单一分化潜能,可通过细胞增殖过程达到细胞生长抑制,从生长周期退出的细胞经诱导激素诱导,开始出现脂肪细胞的表型,     

西红花酸对3T3-L1前脂细胞增殖和分化的影响

目的：观察西红花酸对3T3-L1前脂细胞增殖分化的影响,并探讨其影响3T3-L1细胞分化的可能作用机制。方法：培养前脂肪细胞3T3-L1,四甲基偶氮唑盐（MTT）法检测西红花酸对其生长活性和增殖的影响;油红O染色和染色比色法分析脂肪细胞的分化程度;逆转录多聚酶联反应（RT-PCR）检测腺苷酸激活蛋白激酶（AMP-activated protein kinase,AMPK）mRNA的表达;Western blot法检测p-AMPK蛋白表达水平。结果：西红花酸高、中剂量（10-5、10-6mol/L）组均可以显著抑制前脂细胞的增殖和分化（P〈0.01）,而低剂量组（10-7mol/L）也可以抑制其增殖、分化（P〈0.05）;各剂量的西红花酸都能够增加AMPK的mRNA的表达、提高p-AMPK蛋白表达水平（P〈0.05）。结论：西红花酸具有抑制前脂细胞增殖分化的作用,可能和增强AMPK的表达有关。     

催产素对3T3-L1脂肪细胞糖脂代谢的影响

目的 观察催产素对3T3-L1脂肪细胞糖脂代谢的影响。方法 3T3-L1前脂肪细胞体外培养,并诱导其分化成熟为脂肪细胞。研究催产素对脂肪细胞葡萄糖消耗量以及三酰甘油、游离脂肪酸和甘油的影响。采用实时荧光定量PCR法检测糖脂代谢相关基因GLUT-1、GLUT-4、ATGT、HSL的m RNA表达。结果 与对照组比较,催产素20、50、100μg/m L组葡萄糖消耗量有所增加,且表现出剂量相关。催产素组较对照组的三酰甘油降低,而甘油和游离脂肪酸增高。催产素50μg/m L组中脂代谢相关基因HSL表达明显高于对照组,糖代谢相关基因GLUT-4 m RNA表达水平增加。结论 催产素处理可减少3T3-L1细胞脂质合成、增加脂质分解作用,并可明显改善脂质积聚。     

三黄汤对3T3-L1脂肪细胞糖脂代谢的影响

目的研究三黄汤(SHD)对胰岛素抵抗3T3-L1脂肪细胞糖脂代谢的作用及可能的调控机制。方法高糖高胰岛素(含地塞米松)诱导3T3-L1脂肪细胞发生胰岛素抵抗,给予对照药物罗格列酮(Ros)或不同浓度SHD干预24 h,检测培养上清中葡萄糖减少(消耗)量、甘油和游离脂肪酸(NEFA)浓度以及细胞内甘油三酯(TG)含量;以2-脱氧-[3H]-葡萄糖摄入法观察脂肪细胞对葡萄糖的转运率;应用反转录-聚合酶链反应(RT-PCR)检测葡萄糖转运体4(GLUT-4)的mRNA表达水平,以Western blot检测GLUT-4蛋白的表达水平。结果与对照组相比,SHD的中高剂量(5、10、20、40 g·L~(-1))能使胰岛素抵抗脂肪细胞的葡萄糖消耗量和葡萄糖的转运率增加(P<0.01)、脂肪细胞内TG降低(P<0.01),细胞上清液中甘油的浓度不同程度增加(P<0.01),并明显减少NEFA的溢出,以上变化在三黄汤5~20g·L~(-1)范围内呈现量效关系;同时,Ros增加葡萄糖消耗、葡萄糖的转运率和细胞内TG积累(P<0.01),对培养上清中甘油、NEFA无明显影响(P>0.05)。SHD中、高剂量与Ros都能不同程度明显上调GLUT-4的mRNA和蛋白表达水平(P<0.01)。结论 SHD能明显增加3T3-L1脂肪细胞的葡萄糖摄取和消耗,促进细胞内TG分解,并减少NEFA溢出,通过调节糖代谢和脂代谢改善胰岛素抵抗。     

褪黑素改善胰岛素抵抗3T3-L1脂肪细胞葡萄糖的摄取

目的研究褪黑素对游离脂肪酸(FFA)诱导的胰岛素抵抗3T3-L1脂肪细胞葡萄糖摄取能力的影响。方法 "鸡尾酒"法培养诱导3T3-L1成纤维细胞分化成脂肪细胞,油红O染色鉴定脂肪细胞形态;利用棕榈酸(300μmol/L)诱导脂肪细胞的胰岛素抵抗,采用液体闪烁法检测细胞葡萄糖摄取能力;检测褪黑素对FFA处理的3T3-L1脂肪细胞的葡萄糖摄取能力的影响。结果 3T3-L1细胞经诱导分化成脂肪细胞,油红O染色呈圆形,脂滴呈典型的"戒环样"形态;用FFA处理上述细胞6 h后,细胞的葡萄糖摄取能力明显降低;褪黑素可以促进FFA处理的3T3-L1脂肪细胞胰岛素介导的葡萄糖摄取。结论 FFA可以降低胰岛素诱导的体外培养的脂肪细胞葡萄糖摄取能力,可能是胰岛素抵抗的病因之一。褪黑素可以干预FFA的作用,增加细胞的葡萄糖摄取能力。     

NYGGF4基因表达沉默对3T3-L1脂肪细胞线粒体动力学的影响

目的 探讨NYGGF4基因表达沉默对3T3-L1成熟脂肪细胞线粒体动力学的影响.方法 以3T3-L1前体脂肪细胞为工具,分别构建NYGGF4基因表达沉默细胞株和空载对照细胞株,通过地塞米松(DEX)、1-甲基-3-异丁基黄嘌呤(MIX)、胰岛素联合方案将前体脂肪细胞诱导分化为成熟脂肪细胞.采用实时荧光定量PCR检测成熟脂肪细胞中线粒体融合基因(Mfn) 1/2、线粒体动态相关基因(Drp)1、线粒体分裂基因(Fis)1的mRNA表达水平和线粒体DNA(mtDNA)拷贝数.结果 NYGGF4基因表达沉默成熟脂肪细胞的Mfn1/2、Drp1表达水平与对照组相仿.NYGGF4基因表达沉默成熟脂肪细胞的Fisl的表达水平显著高于对照组(P＜0.05).结论 在3T3-L1脂肪细胞中,NYGGF4基因表达沉默可显著上调Fisl基因的表达水平,提示NYGGF4基因表达沉默可能通过影响线粒体分裂从而影响成熟脂肪细胞线粒体动力学.     

蕨菜超临界萃取物化学成分及其抑制3T3-L1前脂肪细胞分化作用研究

目的分析蕨菜超临界CO_2萃取物(SFE-PA)的化学成分,并探究萃取物对3T3-L1前脂肪细胞分化的抑制作用及机制。方法采用GC-MS分析SFE-PA主要化学成分。体外培养3T3-L1前脂肪细胞,构建脂肪细胞分化的细胞模型,MTT法测定细胞毒性,采用油红O染色法分析SFE-PA对脂肪细胞分化的抑制作用,利用qRT-PCR检测脂肪细胞分化中相关基因的mRNA表达水平。结果从SFE-PA中共鉴定出10种化合物,主要成分有4,4,5,7,8-五甲基-二氢香豆素(36.07%)、β-谷甾醇(25.66%)、4-氨基-7-二乙氨基-香豆素(8.26%)、棕榈酸(5.05%)等。SFE-PA浓度依赖性地抑制3T3-L1前脂肪细胞分化,并减少细胞中脂质的沉积。同时,SFE-PA明显下调PPARγ、CEBPα、SREBP-1c、FAS、ACC的mRNA表达水平。结论 SFE-PA具有明显抑制3T3-L1前脂肪细胞分化的作用,这一作用与其调控脂肪细胞分化转录调控因子和脂质合成相关基因等密切相关,而高含量的酚类、醇类化合物可能是其发挥作用的物质基础。     

3T3-L1前脂肪细胞分化过程中miRNAs基因的表达变化

目的:探讨3T3-L1前脂肪细胞诱导分化过程中miRNAs基因的表达变化。方法:运用经典的"激素鸡尾酒"法建立3T3-L1前脂肪细胞分化模型。采用实时定量聚合酶链式反应方法检测不同时相点(0d、2h、2d、4d)细胞分化相关标志物的表达和20种miRNAs的表达变化,采用生物信息学方法对变化显著的miRNAs进行靶基因预测。结果:成功建立3T3-L1前脂肪细胞分化模型。不同时相点细胞分化相关标志物基因水平提示3T3-L1前脂肪细胞分化为脂肪细胞。20种miRNAs中以miR-126、miR-214、miR-320、miR-351的表达最为显著。靶基因预测结果显示,miR-126靶基因有影响细胞增殖的转录因子Crk、代谢相关基因Irs1等;miR-214靶基因有转录因子Zbtb20、Kpna1等;miR-320靶基因有影响代谢相关基因Igf2bp3、Gxylt1等;miR-351靶基因有Myt1、Mcl1、Bmf等。结论:miR-126、miR-214、miR-320、miR-351可通过影响基因转录及细胞代谢水平,从而对3T3-L1前脂肪细胞分化发挥作用,为开发治疗肥胖等疾病的新药提供了新的研究思路。     

海地瓜硫酸软骨素对3T3-L1前脂肪细胞增殖和分化的影响

目的研究海地瓜硫酸软骨素(Acaudina Molpadioideschondroitin sulfate,AM-CHS)对3T3-L1前脂肪细胞增殖和分化的影响,并探讨其作用机制。方法采用传统的鸡尾酒诱导剂诱导分化3T3-L1前脂肪细胞,以MTT法检测AM-CHS对3T3-L1前脂肪细胞及不同分化阶段3T3-L1细胞增殖活性的影响;分别采用油红O染色和甘油三酯(triglycerides,TG)含量测定法评价其对3T3-L1前脂肪细胞分化的影响。采用RT-PCR法检测脂肪细胞中过氧化物酶体增殖体激活受体γ(peroxisome proliferators-activated receptors gamma,PPARγ)、CCAAT增强子结合蛋白α(CCAAT/enhancer bind-ing protein alpha,C/EBPα)、固醇调节元件结合蛋白-1c(ste-rol regulatory element binding protein-1c,SREBP-1c)等分化相关基因的mRNA表达水平。结果 AM-CHS能明显抑制3T3-L1前脂肪细胞和成熟脂肪细胞的增殖,抑制3T3-L1前脂肪细胞的分化过程,以对分化早期的抑制作用最强。RT-PCR结果表明,AM-CHS能明显降低脂肪细胞PPARγ、C/EBPα和SREBP-1c mRNA的表达。结论海地瓜AM-CHS能明显抑制3T3-L1前脂肪细胞的增殖和分化,其作用机制与下调分化相关基因PPARγ、C/EBPα和SREBP-1c的表达有关。     

Anti-obesity effects of seaweeds of Jeju Island on the differentiation of 3T3-L1 preadipocytes and obese mice fed a high-fat diet

The seaweeds were collected from the coast of Jeju Island, South Korea. We investigated ethanol extracts from seaweed as potential antiobesity agents by testing their effect on adipogenic differentiation in 3T3-L1 cells. Among the red algae extracts tested, the Plocamium telfairiae extract (PTE) showed the highest inhibitory effect on lipogenesis in adipocytes and, thus, was selected as a potential antiobesity agent. PTE treatment significantly decreased the expression of the adipogenic-specific proteins peroxisome proliferator-activated receptor-γ, CCAAT/enhancer-binding protein-α, sterol regulatory element-binding protein 1, and fatty acid-binding protein 4 compared with that in the untreated 3T3-L1 cells. PTE also inhibited high-fat diet (HFD)-induced obesity in male C57BL/6 mice. Oral administration of PTE significantly reduced the body weight, fatty liver, amount of white adipose tissue, and levels of triglyceride and glucose in the tested animals. Taken together, these data demonstrate that PTE can be developed as a therapeutic agent for obesity.     

Bisphenol a accelerates terminal differentiation of 3T3-L1 cells into adipocytes through the phosphatidylinositol 3-kinase pathway.

In order to identify whether bisphenol A (BPA) acts as an adipogenic agent, following the hormonal induction of differentiation into adipocytes, 3T3-L1 cells were treated for six days with BPA alone. Treatment with BPA increased the triacylglycerol (TG) content of the cultures, increased the percentage of Oil Red O-staining cells in the cultures, and increased the levels of lipoprotein lipase (LPL) and adipocyte-specific fatty acid binding protein (aP2) mRNAs. These findings indicate that BPA was able to accelerate terminal differentiation of 3T3-L1 cells into adipocytes. LY294002, a chemical inhibitor of phosphatidylinositol 3-kinase (PI 3-kinase), blocked completely the increasing effect of BPA on TG accumulation and expression of LPL and aP2 mRNAs. Western blot analysis revealed that BPA increased the level of phosphorylated Akt kinase. Based on these findings, we concluded that BPA acted through the PI 3-kinase and Akt kinase pathway, resulting in increased TG accumulation and expression of adipocyte genes. The structure-activity relationship for BPA-related chemicals was examined. Eight derivatives of BPA (three diphenylalkanes with different substituents at the central carbon atom, three diphenylalkanes with ester bonds on hydroxyl groups in the phenolic rings, one bisphenol consisting of a sulphur atom at the central position, one chemical with cyanic groups, instead of hydroxyl groups, in the phenolic rings) accelerated terminal adipocyte differentiation and their potencies to increase TG accumulation were 73-97% of that of BPA. Two diphenylalkanes with ether bonds on hydroxyl groups and two alkylphenols (4-nonylphenol and 4-tert-octylphenol) did not have the ability to accelerate terminal adipocyte differentiation.     

Effects of 4-nonylphenol on adipogenesis in 3T3-L1 preadipocytes and C3H/10T1/2 mesenchymal stem cells

Obesogens are a subset of endocrine disruptor chemicals (EDCs) that cause obesity. The typical EDC 4-nonylphenol (4-NP) has been identified as an obesogen. However, the in vitro effects of 4-NP on adipogenesis remain unclear. In this study, 3T3-L1 preadipocytes and C3H/10T1/2 mesenchymal stem cells (MSCs) were used to investigate the influence of 4-NP on adipogenesis. The differentiation protocols for 3T3-L1 preadipocytes and C3H/10T1/2 MSCs took 8 and 12 days, respectively, beginning at Day 0. In differentiated 3T3-L1 preadipocytes, 20 μM 4-NP decreased cell viability on Days 4 and 8. Exposure to 4-NP inhibited triglyceride (TG) accumulation and adipogenic marker expression on Days 0–8, but the inhibitory effects were weaker on Days 2–8. The protein expression of pSTAT3 or STAT3 decreased on Days 0–8 and 2–8. Conversely, 4-NP promoted TG accumulation and the adipogenic marker expression in C3H/10T1/2 adipocytes. The opposing effects were attributed to physiological differences between the two cell lines. The 3T3-L1 preadipocytes are dependent on mitotic clonal expansion (MCE) to drive differentiation, while C3H/10T1/2MSCs and human preadipocytes are not. Additionally, 4-NP downregulated β-catenin expression in C3H/10T1/2 adipocytes. Accordingly, we hypothesized that 4-NP promotes adipogenesis. The role of the canonical Wnt pathway in the promotion of adipogenesis by 4-NP requires further validation. This study provides new insights into the mechanisms and appropriate risk management of 4-NP.