Downregulation of de Novo Fatty Acid Synthesis in Subcutaneous Adipose Tissue of Moderately Obese Women

Int J Mol Sci. 2015 Dec 16;16(12):29911-22. doi: 10.3390/ijms161226206.

Abstract

The purpose of this work was to evaluate the expression of fatty acid metabolism-related genes in human adipose tissue from moderately obese women. We used qRT-PCR and Western Blot to analyze visceral (VAT) and subcutaneous (SAT) adipose tissue mRNA expression involved in de novo fatty acid synthesis (ACC1, FAS), fatty acid oxidation (PPARα, PPARδ) and inflammation (IL6, TNFα), in normal weight control women (BMI < 25 kg/m², n = 35) and moderately obese women (BMI 30-38 kg/m², n = 55). In SAT, ACC1, FAS and PPARα mRNA expression were significantly decreased in moderately obese women compared to controls. The downregulation reported in SAT was more pronounced when BMI increased. In VAT, lipogenic-related genes and PPARα were similar in both groups. Only PPARδ gene expression was significantly increased in moderately obese women. As far as inflammation is concerned, TNFα and IL6 were significantly increased in moderate obesity in both tissues. Our results indicate that there is a progressive downregulation in lipogenesis in SAT as BMI increases, which suggests that SAT decreases the synthesis of fatty acid de novo during the development of obesity, whereas in VAT lipogenesis remains active regardless of the degree of obesity.

Keywords: adipose tissue; de novo fatty acid synthesis; fatty acid metabolism; moderate obesity.

MeSH terms

  • Cohort Studies
  • Down-Regulation / genetics*
  • Fatty Acids / biosynthesis
  • Female
  • Glucose / metabolism
  • Humans
  • Inflammation / genetics
  • Intra-Abdominal Fat / enzymology
  • Intra-Abdominal Fat / metabolism*
  • Intra-Abdominal Fat / pathology
  • Lipogenesis / genetics
  • Middle Aged
  • Obesity / genetics*
  • Oxidation-Reduction
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Subcutaneous Fat / enzymology
  • Subcutaneous Fat / metabolism*
  • Subcutaneous Fat / pathology

Substances

  • Fatty Acids
  • RNA, Messenger
  • Glucose