School of Biotechnology, Yeungnam University, Gyeongsan 712-749, Republic of Korea.
In Vitro Cell Dev Biol Anim. 2012 May;48(5):326-33. doi: 10.1007/s11626-012-9512-1. Epub 2012 May 2.
Intramuscular long-chain fatty acids (LCFAs) play an important role in energy production and initiation of mitochondrial oxidation of lipids. Herein, we report a natural porcine placenta steroid extract (PPSE) that stimulates transdifferentiation and lipid accumulation in bovine myogenic satellite cells (MSCs). The steroids hormones in PPSE were analyzed using enzyme-linked immunosorbant assay and presence of LCFA was established using gas chromatography. At 70% confluent growth, cells were treated with PPSE, LCFAs, transdifferentiation cocktail and commercially available steroid hormones. The working concentrations of all chemicals were manipulated similar to PPSE. The cells were observed for morphological changes and subjected to quantitative analysis of lipid deposition on Days 2, 4, and 6 of treatment. PPSE-treated MSCs exclusively transformed into lipid-accumulated adipose-like cells (ALCs). However, myotubes or adipocytes were formed in cells treated with other chemicals. Expression of different genes was studied to ascertain the molecular mechanism involved in ALC formation. CD36, fatty acid binding protein 4, and peroxisome proliferator-activated receptor-gamma were up-regulated. The expression of CD36 was established through immunocyto-chemical analysis. A viability assay was used to confirm the effect of PPSE on proliferation of MSCs. Hence, a natural steroid extract from porcine was found as a nontoxic mixture, which induces lipid accumulation and transdifferentiation of MSCs to ALCs. From the gene expression studies, it was established that the extract works almost in homogenous manner with other lipid inducers.
肌内长链脂肪酸 (LCFA) 在能量产生和脂质线粒体氧化的启动中发挥重要作用。在此，我们报告了一种天然猪胎盘类固醇提取物 (PPSE)，它可刺激牛肌卫星细胞 (MSCs) 的转分化和脂质积累。使用酶联免疫吸附测定法分析 PPSE 中的类固醇激素，并使用气相色谱法确定 LCFA 的存在。在 70%汇合生长时，用 PPSE、LCFA、转分化鸡尾酒和市售类固醇激素处理细胞。所有化学物质的工作浓度均与 PPSE 相似进行操作。观察细胞形态变化，并在处理的第 2、4 和 6 天对脂质沉积进行定量分析。仅用 PPSE 处理的 MSC 会特异地转化为富含脂质的脂肪样细胞 (ALC)。然而，在用其他化学物质处理的细胞中形成了肌管或脂肪细胞。研究了不同基因的表达，以确定 ALC 形成所涉及的分子机制。CD36、脂肪酸结合蛋白 4 和过氧化物酶体增殖物激活受体-γ 上调。通过免疫细胞化学分析确定了 CD36 的表达。使用活力测定法证实了 PPSE 对 MSC 增殖的影响。因此，从猪中发现了一种天然的类固醇提取物作为无毒混合物，可诱导 MSC 脂质积累和向 ALC 的转分化。从基因表达研究中可以确定，该提取物与其他脂质诱导剂几乎以均匀的方式发挥作用。
