Reduced expression of uncoupling proteins-2 and -3 in adipose tissue in post-obese patients submitted to biliopancreatic diversion.
OBJECTIVE
Little is known about the physiological role and the regulation of uncoupling proteins-2 and -3 (UCP-2 and -3) in adipose tissue. We investigated whether the expression of UCP-2 and -3 in adipose tissue was affected by weight loss due to a biliopancreatic diversion (BPD) and related to the daily energy expenditure (24-h EE).


METHODS
Ten morbidly obese subjects (mean body mass index +/- s.e.m.=49.80 +/- 2.51 kg/m(2)) were studied before and 18+/-2 Months after BPD.


METHODS
We determined body composition using tritiated water and 24-h EE in a respiratory chamber. Adipose tissue UCP-2 and -3 mRNA, plasma insulin, glucose, free fatty acids (NEFA), free triiodothyronine (FT3), free thyroxine (FT4) and leptin were assayed before and after BPD.


RESULTS
BPD treatment resulted in a marked weight loss (P<0.001) mainly due to a fat mass reduction. A significant decrease in 24-h EE/fat-free mass (FFM) (P<0.05) and in UCP-2 (P<0.05) and UCP-3 (P<0.05) mRNA was observed. A significant reduction in plasma insulin, glucose, NEFA, FT3, FT4 and leptin was seen after BPD. The decline in plasma leptin and FFA was tightly correlated with the decrease in both UCP-2 and -3. A significant correlation was found between changes in FT3 and variations in 24-h EE (r=0.64, P<0.05). In a multiple-regression analysis changes in 24-h EE/FFM after BPD were significantly correlated with changes in UCP-3 expression (P<0.05).


CONCLUSIONS
These findings suggest that UCPs in adipose tissue may play a role in the reduction in 24-h EE observed in post-obese individuals.
Vettor
Roberto
R
Endocrine Metabolic Laboratory, Internal Medicine, Department of Medical and Surgical Sciences, University of Padua, via Ospedale 105, 35128 Padua, Italy. roberto.vettor@unipd.it
Mingrone
Geltrude
G
Manco
Melania
M
Granzotto
Marnie
M
Milan
Gabriella
G
Scarda
Alessandro
A
Lombardi
Annamaria
A
Greco
Aldo Virgilio
AV
Federspil
Giovanni
G
D000273:Adipose Tissue / Q000378:metabolism*; D000328:Adult; D000368:Aged; D015904:Biliopancreatic Diversion; D001823:Body Composition; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002940:Circadian Rhythm; D004734:Energy Metabolism; D005260:Female; D006801:Humans; D007333:Insulin Resistance; D007473:Ion Channels; D020738:Leptin / Q000097:blood; D008297:Male; D026901:Membrane Transport Proteins; D008875:Middle Aged; D024101:Mitochondrial Proteins; D009767:Obesity, Morbid / Q000378:metabolism* / Q000601:surgery*; D011184:Postoperative Period; D011506:Proteins / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D013963:Thyroid Hormones / Q000097:blood; D000071246:Uncoupling Protein 2; D000071247:Uncoupling Protein 3
D002352:Carrier Proteins; D007473:Ion Channels; D020738:Leptin; D026901:Membrane Transport Proteins; D024101:Mitochondrial Proteins; D011506:Proteins; D012333:RNA, Messenger; D013963:Thyroid Hormones; C000604389:UCP2 protein, human; C000604392:UCP3 protein, human; D000071246:Uncoupling Protein 2; D000071247:Uncoupling Protein 3