Department of General and Endocrinological Surgery, Medical University of Białystok, Białystok, Poland.
Department of Dermatology and Venereology, Medical University of Białystok, Białystok, Poland.
Obesity (Silver Spring). 2019 Mar;27(3):444-453. doi: 10.1002/oby.22405. Epub 2019 Feb 5.
Accelerated transmembrane transport of long-chain fatty acids dependent on fatty acid transporters is responsible for lipid accumulation and, eventually, the development of metabolic syndrome. This study determined the content of lipids (ceramide [CER], diacylglycerol [DAG], triacylglycerol, and free fatty acid [FFA]) and the expression of fatty acid translocase (FAT/CD36) and plasma membrane fatty acid-binding protein in visceral adipose tissue (VAT) and subcutaneous adipose tissue of women with morbid obesity without metabolic syndrome (MetSx-) or with metabolic syndrome (MetSx+) and compared the results with those of lean controls without metabolic syndrome.
Lipid content and fatty acid composition in each lipid subclass were estimated by gas liquid chromatography. For total, plasma membrane, and mitochondrial expression of fatty acid transporters, subfractionation with subsequent Western blot technique was used.
A greater content of triacylglycerol in VAT of participants with obesity (MetSx-) was found. However, only the MetSx+ subjects had increased content of CER in VAT in relation to subcutaneous adipose tissue in MetSx+ and lean individuals. This was accompanied by increased total and membrane expression of FAT/CD36 in VAT in MetSx+ subjects. Accordingly, mitochondrial expression of FAT/CD36 and plasma membrane fatty acid-binding protein was decreased in both groups of subjects with obesity.
Metabolic syndrome is associated with the accumulation of CER in VAT, possibly related to increased FAT/CD36 protein expression.
长链脂肪酸依赖脂肪酸转运蛋白的跨膜转运加速是脂质积累的原因,最终导致代谢综合征的发生。本研究测定了内脏脂肪组织(VAT)和无代谢综合征(MetSx-)或代谢综合征(MetSx+)的病态肥胖女性皮下脂肪组织中脂肪酸转运蛋白(FAT/CD36)和质膜脂肪酸结合蛋白的表达以及脂质(神经酰胺[CER]、二酰基甘油[DAG]、三酰基甘油和游离脂肪酸[FFA])的含量,并将结果与无代谢综合征的瘦对照组进行比较。
通过气相色谱法估计每个脂质亚类的脂质含量和脂肪酸组成。对于脂肪酸转运蛋白的总、质膜和线粒体表达,使用亚分级分离和随后的 Western blot 技术。
肥胖患者(MetSx-)的 VAT 中三酰基甘油含量较高。然而,只有 MetSx+患者的 VAT 中 CER 含量增加,与 MetSx+和瘦个体的皮下脂肪组织相比。这伴随着 VAT 中 FAT/CD36 的总蛋白和膜蛋白表达增加。因此,两组肥胖患者的线粒体 FAT/CD36 和质膜脂肪酸结合蛋白表达均降低。
代谢综合征与 VAT 中 CER 的积累有关,这可能与 FAT/CD36 蛋白表达增加有关。