Adipose tissue of control and ex-obese patients exhibit differences in blood vessel content and resident mesenchymal stem cell population.
BACKGROUND
The normal function of white adipose tissue is disturbed in obesity. After weight loss that follows bariatric surgery, ex-obese patients undergo plastic surgery to remove residual tissues and it is not known whether their adipose tissue returns to its original state. The aim of this study was to compare the white adipose tissue composition of ex-obese with control patients with regard to blood vessels and resident mesenchymal stem cells (MSC).


METHODS
Quantification of blood vessels was performed on histological sections of adipose tissue stained with hematoxylin and eosin and for von Willebrand antigen. MSC were induced to the adipogenic and osteogenic lineages by specific inductive culture media. Expression of PPARgamma2 was analyzed by reverse transcription polymerase chain reaction.


RESULTS
Ex-obese adipose tissue showed a higher number (p = 0.0286) of small (107.3 +/- 22.0) and large (22.5 +/- 6.4) blood vessels, when compared to control patients (42.0 +/- 24.4 and 7.2 +/- 2.2, respectively) and they also occupied a larger area (control versus ex-obese, p = 0.0286). Adipose tissue MSC from both groups of patients expressed PPARgamma2 and were equally able to differentiate to the osteogenic lineage, but ex-obese MSC showed a higher adipogenic potential when induced in vitro (p < 0.05).


CONCLUSIONS
The higher number of adipose tissue blood vessels in ex-obese patients explains the excessive bleeding observed during their plastic surgery. The presence of more committed cells to the adipogenic lineage may favor the easy weight regain that occurs in ex-obese patients. These results show that, after extensive weight loss, adipose tissue cell composition was not totally restored.
Baptista
Leandra Santos
LS
APABCAM, Clementino Fraga Filho University Hospital, Federal University of Rio de Janeiro, Rodolpho Rocco, 255, Rio de Janeiro 21941-913, RJ, Brazil. leandra.baptista@gmail.com
da Silva
Karina Ribeiro
KR
da Pedrosa
Carolina Silva Gouveia
CS
Claudio-da-Silva
Cesar
C
Carneiro
João Regis Ivar
JR
Aniceto
Marcelo
M
de Mello-Coelho
Valéria
V
Takiya
Christina Maeda
CM
Rossi
Maria Isabel Doria
MI
Borojevic
Radovan
R
D000328:Adult; D015992:Body Mass Index; D016022:Case-Control Studies; D002452:Cell Count; D005260:Female; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000502:physiology*; D008875:Middle Aged; D009765:Obesity / Q000473:pathology* / Q000503:physiopathology* / Q000601:surgery; D047495:PPAR gamma / Q000378:metabolism; D050151:Subcutaneous Fat / Q000098:blood supply* / Q000378:metabolism / Q000473:pathology*; D015431:Weight Loss
D047495:PPAR gamma