Gender effects on adrenergic receptor expression and lipolysis in white adipose tissue of rats.
OBJECTIVE
To investigate the effects of short-term (15 days) cafeteria-diet feeding on the expression of alpha- and beta-adrenergic receptors (AR) and its association with lipolytic stimulation in isolated retroperitoneal white adipocytes.


METHODS
Six female and 6 male Wistar rats (4 weeks old) were fed a cafeteria diet plus standard diet for 15 days. The remaining 12 age- and sex-matched rats received a standard diet only. White retroperitoneal adipose tissue was isolated and used for the determination of both alpha(2) and beta-AR expression and for in vitro studies of lipolytic activity.


RESULTS
In female control rats, we found higher lipolytic capacities located at the postreceptor level and a lower alpha(2)/beta(3)-AR ratio than male rats. Cafeteria-diet feeding for 15 days decreased lipolytic activity in both male and female rats and altered the alpha(2A)- and beta(3)-AR protein levels with an increase of alpha(2A)-AR in males and a beta(3)-AR decrease in females.


CONCLUSIONS
Our results indicate that a 15-day cafeteria-diet feeding induced an increase in the alpha(2)/beta(3)-AR balance and impaired adipose tissue lipolytic activity, which was higher in males and may contribute to the development of increased fat mass. The higher functionality of alpha(2)-AR, together with the minor role developed by beta(3)-AR and lower lipolytic capacities located at the postreceptor level in cafeteria-diet-fed male rats compared with female rats, may be responsible for the gender-dependent differences observed in this study.
Lladó
Isabel
I
Laboratori de Biologia Molecular, Nutrició i Biotecnologia, Departament de Biologia Fonamental i Ciències de la Salut, Universitat de les Illes Balears, Palma de Mallorca, Spain. isabel.llado@uib.es
Rodríguez-Cuenca
Sergio
S
Pujol
Esperanza
E
Monjo
Marta
M
Estrany
M Elena
ME
Roca
Pilar
P
Palou
Andreu
A
D017667:Adipocytes / Q000166:cytology; D000273:Adipose Tissue / Q000737:chemistry* / Q000378:metabolism*; D000818:Animals; D015153:Blotting, Western; D001835:Body Weight; D048429:Cell Size; D004041:Dietary Fats / Q000008:administration & dosage; D002149:Energy Intake; D005260:Female; D008066:Lipolysis; D008297:Male; D009929:Organ Size; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D018341:Receptors, Adrenergic, alpha-2 / Q000032:analysis* / Q000235:genetics; D022702:Receptors, Adrenergic, beta-3 / Q000032:analysis* / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012727:Sex Characteristics
D004041:Dietary Fats; D012333:RNA, Messenger; D018341:Receptors, Adrenergic, alpha-2; D022702:Receptors, Adrenergic, beta-3