FAM13A affects body fat distribution and adipocyte function

Nat Commun. 2020 Mar 19;11(1):1465. doi: 10.1038/s41467-020-15291-z.

Abstract

Genetic variation in the FAM13A (Family with Sequence Similarity 13 Member A) locus has been associated with several glycemic and metabolic traits in genome-wide association studies (GWAS). Here, we demonstrate that in humans, FAM13A alleles are associated with increased FAM13A expression in subcutaneous adipose tissue (SAT) and an insulin resistance-related phenotype (e.g. higher waist-to-hip ratio and fasting insulin levels, but lower body fat). In human adipocyte models, knockdown of FAM13A in preadipocytes accelerates adipocyte differentiation. In mice, Fam13a knockout (KO) have a lower visceral to subcutaneous fat (VAT/SAT) ratio after high-fat diet challenge, in comparison to their wild-type counterparts. Subcutaneous adipocytes in KO mice show a size distribution shift toward an increased number of smaller adipocytes, along with an improved adipogenic potential. Our results indicate that GWAS-associated variants within the FAM13A locus alter adipose FAM13A expression, which in turn, regulates adipocyte differentiation and contribute to changes in body fat distribution.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adipocytes / metabolism*
  • Adipogenesis / genetics
  • Animals
  • Body Fat Distribution*
  • Cell Differentiation / genetics
  • GTPase-Activating Proteins / genetics*
  • GTPase-Activating Proteins / metabolism
  • Gene Knockdown Techniques
  • Genetic Loci
  • Genome-Wide Association Study
  • HEK293 Cells
  • Humans
  • Insulin Resistance / genetics
  • Intra-Abdominal Fat / metabolism
  • Male
  • Metabolomics
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Phenotype
  • Polymorphism, Single Nucleotide / genetics
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Subcutaneous Fat / metabolism

Substances

  • FAM13A protein, human
  • Fam13a protein, mouse
  • GTPase-Activating Proteins
  • RNA, Messenger