Surgical removal of perirenal and epididymal adipose tissue decreases serum leptin concentration and increases lipogenic enzyme activities in remnant adipose tissue of old rats.
BACKGROUND
The rate of lipogenesis and gene expression of lipogenic enzymes in white adipose tissue (WAT) of rats decreases with age. Previously, we showed the inverse relationship between serum leptin concentration and lipogenic enzymes activities in WAT of ageing rats. Based on those results, we postulated that leptin could play some role in the downregulation of lipogenic enzyme genes expression in WAT of old rats.


OBJECTIVE
To further test this hypothesis, in the present paper we examined the effect of surgical removal of perirenal and epididymal WAT on serum leptin concentration and lipogenic enzymes activities in remnant adipose tissue of old rats.


METHODS
One-year-old rats, which display a high serum leptin concentration and low lipogenic enzyme activities in WAT, were subjected to surgical removal of the perirenal and epididymal WAT. Two months after the surgery, the serum leptin concentration and lipogenic enzyme activities in remnant WAT were compared to the serum leptin concentration and lipogenic enzyme activities measured in adipose tissue collected during the surgery.


RESULTS
WAT removal resulted in an approximately 6-fold decrease of serum leptin concentration and about a 2-fold increase of lipogenic enzyme activities in remnant adipose tissue.


CONCLUSIONS
These results indicate that interventions designed to reduce abdominal adipose tissue mass can change the lipogenic activity of remnant adipose tissue. Additionally, leptin could be one of the factors contributing to the downregulation of the genes expression of lipogenic enzymes during ageing in rats.
Nogalska
Anna
A
Department of Biochemistry, Medical University of Gdansk, Gdansk, Poland.
Stelmanska
Ewa
E
Sledzinski
Tomasz
T
Swierczynski
Julian
J
D050153:Abdominal Fat / Q000201:enzymology / Q000502:physiology / Q000601:surgery; D052436:Adipose Tissue, White / Q000201:enzymology* / Q000502:physiology / Q000601:surgery; D000375:Aging / Q000097:blood* / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D015536:Down-Regulation; D004822:Epididymis / Q000502:physiology / Q000601:surgery; D007328:Insulin / Q000097:blood; D007668:Kidney / Q000502:physiology / Q000601:surgery; D020738:Leptin / Q000097:blood*; D050155:Lipogenesis / Q000235:genetics / Q000502:physiology*; D008297:Male; D008954:Models, Biological; D051381:Rats; D017208:Rats, Wistar
D001786:Blood Glucose; D007328:Insulin; D020738:Leptin