Saturated fatty acids in human visceral adipose tissue are associated with increased 11- β-hydroxysteroid-dehydrogenase type 1 expression.
BACKGROUND
Visceral fat accumulation is associated with metabolic disease. It is therefore relevant to study factors that regulate adipose tissue distribution. Recent data shows that overeating saturated fatty acids promotes greater visceral fat storage than overeating unsaturated fatty acids. Visceral adiposity is observed in states of hypercortisolism, and the enzyme 11-β-hydroxysteroid-dehydrogenase type 1 (11β-hsd1) is a major regulator of cortisol activity by converting inactive cortisone to cortisol in adipose tissue. We hypothesized that tissue fatty acid composition regulates body fat distribution through local effects on the expression of 11β-hsd1 and its corresponding gene (HSD11B1) resulting in altered cortisol activity.


RESULTS
Visceral- and subcutaneous adipose tissue biopsies were collected during Roux-en-Y gastric bypass surgery from 45 obese women (BMI; 41±4 kg/m2). The fatty acid composition of each biopsy was measured and correlated to the mRNA levels of HSD11B1. 11β-hsd1 protein levels were determined in a subgroup (n=12) by western blot analysis. Our main finding was that tissue saturated fatty acids (e.g. palmitate) were associated with increased 11β-hsd1 gene- and protein-expression in visceral but not subcutaneous adipose tissue.


CONCLUSIONS
The present study proposes a link between HSD11B1 and saturated fatty acids in visceral, but not subcutaneous adipose tissue. Nutritional regulation of visceral fat mass through HSD11B1 is of interest for the modulation of metabolic risk and warrants further investigation.
Department of Medicine, Karolinska Institutet, Karolinska University Hospital, Huddinge, Stockholm, Sweden. paul.petrus@ki.se.
Paul
P
Petrus
Clinical Nutrition and Metabolism, Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden. fredrik.rosqvist@pubcare.uu.se.
Fredrik
F
Rosqvist
Department of Surgical Sciences, Uppsala University Hospital, Uppsala University, Uppsala, Sweden. david.edholm@surgsci.uu.se.
David
D
Edholm
Department of Medicine, Karolinska Institutet, Karolinska University Hospital, Huddinge, Stockholm, Sweden. niklas.mejhert@ki.se.
Niklas
N
Mejhert
Department of Medicine, Karolinska Institutet, Karolinska University Hospital, Huddinge, Stockholm, Sweden. peter.arner@ki.se.
Peter
P
Arner
Department of Medicine, Karolinska Institutet, Karolinska University Hospital, Huddinge, Stockholm, Sweden. ingrid.dahlman@ki.se.
Ingrid
I
Dahlman
Department of Medicine, Karolinska Institutet, Karolinska University Hospital, Huddinge, Stockholm, Sweden. mikael.ryden@ki.se.
Mikael
M
Rydén
Department of Surgical Sciences, Uppsala University Hospital, Uppsala University, Uppsala, Sweden. magnus.sundbom@surgsci.uu.se.
Magnus
M
Sundbom
Clinical Nutrition and Metabolism, Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden. ulf.riserus@pubcare.uu.se.
Ulf
U
Risérus
D043205:11-beta-Hydroxysteroid Dehydrogenase Type 1 / Q000378:metabolism*; D000328:Adult; D015153:Blotting, Western; D005227:Fatty Acids / Q000032:analysis*; D005260:Female; D015870:Gene Expression; D006801:Humans; D050152:Intra-Abdominal Fat / Q000737:chemistry* / Q000201:enzymology
D005227:Fatty Acids; D043205:11-beta-Hydroxysteroid Dehydrogenase Type 1; C468386:HSD11B1 protein, human