Local Androgen Inactivation in Abdominal Visceral Adipose Tissue Export

@article{citeulike:1321482, abstract = {We examined the expression and activity of two enzymes from the aldoketoreductase (AKR) family 1C, namely type 5 17{beta}-hydroxysteroid dehydrogenase (17{beta}-HSD-5, AKR1C3) and type 3 3{alpha}-hydroxysteroid dehydrogenase (3{alpha}-HSD-3, AKR1C2) in female sc and omental adipose tissue and in preadipocyte primary cultures. 17{beta}-HSD-5 preferentially synthesizes testosterone from the inactive adrenal precursor androstenedione, whereas 3{alpha}-HSD-3 inactivates dihydrotestosterone. mRNAs of both enzymes were detected in adipose tissue from the omental and sc compartments. Real-time PCR quantification indicated a 3-fold higher 3{alpha}-HSD-3 expression compared with 17{beta}-HSD-5, and the expression of both enzymes tended to be higher in the sc vs. the omental depot. Accordingly, dose-response and time-course experiments performed in preadipocyte primary cultures indicated that 3{alpha}-HSD activity was higher than 17{beta}-HSD activity (13-fold maximum velocity difference). We measured 3{alpha}-HSD activity in omental and sc adipose tissue samples of 32 women for whom body composition and body fat distribution were evaluated by dual-energy x-ray absorptiometry and CT, respectively. We found that androgen inactivation in omental adipose tissue through 3{alpha}-HSD activity was significantly higher in women with elevated vs. low visceral adipose tissue accumulation (1.7-fold difference; P < 0.05). Moreover, omental adipose tissue 3{alpha}-HSD activity was positively and significantly associated with CT-measured visceral adipose tissue (r = 0.43; P < 0.02) and omental adipocyte diameter (r = 0.42; P < 0.02). These results indicate that local androgen inactivation is a predominant reaction in female abdominal adipose tissue, with the greatest conversion rates observed in the presence of abdominal visceral obesity. Increased androgen inactivation in omental adipose tissue of abdominally obese women may impact locally on the regulation of adipocyte metabolism. 10.1210/jc.2003-030535}, author = {Blouin, Karine and Richard, Christian and Belanger, Chantal and Dupont, Pierre and Daris, Marleen and Laberge, Philippe and Luu-The, Van and Tchernof, Andre}, citeulike-article-id = {1321482}, citeulike-linkout-0 = {http://dx.doi.org/10.1210/jc.2003-030535}, citeulike-linkout-1 = {http://jcem.endojournals.org/cgi/content/abstract/88/12/5944}, citeulike-linkout-2 = {http://view.ncbi.nlm.nih.gov/pubmed/14671194}, citeulike-linkout-3 = {http://www.hubmed.org/display.cgi?uids=14671194}, day = {1}, doi = {10.1210/jc.2003-030535}, journal = {J Clin Endocrinol Metab}, keywords = {17bhsd5, abdominal, adipose, akr, androgen, distribution, visceral}, month = {December}, number = {12}, pages = {5944--5950}, posted-at = {2007-05-23 14:28:12}, priority = {2}, title = {Local Androgen Inactivation in Abdominal Visceral Adipose Tissue}, url = {http://dx.doi.org/10.1210/jc.2003-030535}, volume = {88}, year = {2003} }

TY - JOUR ID - citeulike:1321482 L3 - citeulike-article-id:1321482 N2 - We examined the expression and activity of two enzymes from the aldoketoreductase (AKR) family 1C, namely type 5 17{beta}-hydroxysteroid dehydrogenase (17{beta}-HSD-5, AKR1C3) and type 3 3{alpha}-hydroxysteroid dehydrogenase (3{alpha}-HSD-3, AKR1C2) in female sc and omental adipose tissue and in preadipocyte primary cultures. 17{beta}-HSD-5 preferentially synthesizes testosterone from the inactive adrenal precursor androstenedione, whereas 3{alpha}-HSD-3 inactivates dihydrotestosterone. mRNAs of both enzymes were detected in adipose tissue from the omental and sc compartments. Real-time PCR quantification indicated a 3-fold higher 3{alpha}-HSD-3 expression compared with 17{beta}-HSD-5, and the expression of both enzymes tended to be higher in the sc vs. the omental depot. Accordingly, dose-response and time-course experiments performed in preadipocyte primary cultures indicated that 3{alpha}-HSD activity was higher than 17{beta}-HSD activity (13-fold maximum velocity difference). We measured 3{alpha}-HSD activity in omental and sc adipose tissue samples of 32 women for whom body composition and body fat distribution were evaluated by dual-energy x-ray absorptiometry and CT, respectively. We found that androgen inactivation in omental adipose tissue through 3{alpha}-HSD activity was significantly higher in women with elevated vs. low visceral adipose tissue accumulation (1.7-fold difference; P < 0.05). Moreover, omental adipose tissue 3{alpha}-HSD activity was positively and significantly associated with CT-measured visceral adipose tissue (r = 0.43; P < 0.02) and omental adipocyte diameter (r = 0.42; P < 0.02). These results indicate that local androgen inactivation is a predominant reaction in female abdominal adipose tissue, with the greatest conversion rates observed in the presence of abdominal visceral obesity. Increased androgen inactivation in omental adipose tissue of abdominally obese women may impact locally on the regulation of adipocyte metabolism. 10.1210/jc.2003-030535 IS - 12 JF - J Clin Endocrinol Metab EP - 5950 TI - Local Androgen Inactivation in Abdominal Visceral Adipose Tissue VL - 88 SP - 5944 KW - 17bhsd5 KW - abdominal KW - adipose KW - akr KW - androgen KW - distribution KW - visceral AU - Blouin, Karine AU - Richard, Christian AU - Belanger, Chantal AU - Dupont, Pierre AU - Daris, Marleen AU - Laberge, Philippe AU - Luu-The, Van AU - Tchernof, Andre PY - 2003/12/01/ UR - http://dx.doi.org/10.1210/jc.2003-030535 ER -