Adipose tissue endocannabinoid system gene expression: depot differences and effects of diet and exercise.
BACKGROUND
Alterations of endocannabinoid system in adipose tissue play an important role in lipid regulation and metabolic dysfunction associated with obesity. The purpose of this study was to determine whether gene expression levels of cannabinoid type 1 receptor (CB1) and fatty acid amide hydrolase (FAAH) are different in subcutaneous abdominal and gluteal adipose tissue, and whether hypocaloric diet and aerobic exercise influence subcutaneous adipose tissue CB1 and FAAH gene expression in obese women.


METHODS
Thirty overweight or obese, middle-aged women (BMI = 34.3 ± 0.8 kg/m2, age = 59 ± 1 years) underwent one of three 20-week weight loss interventions: caloric restriction only (CR, N = 9), caloric restriction plus moderate-intensity aerobic exercise (CRM, 45-50% HRR, N = 13), or caloric restriction plus vigorous-intensity aerobic exercise (CRV, 70-75% HRR, N = 8). Subcutaneous abdominal and gluteal adipose tissue samples were collected before and after the interventions to measure CB1 and FAAH gene expression.


RESULTS
At baseline, FAAH gene expression was higher in abdominal, compared to gluteal adipose tissue (2.08 ± 0.11 vs. 1.78 ± 0.10, expressed as target gene/β-actin mRNA ratio × 10-3, P < 0.05). Compared to pre-intervention, CR did not change abdominal, but decreased gluteal CB1 (Δ = -0.82 ± 0.25, P < 0.05) and FAAH (Δ = -0.49 ± 0.14, P < 0.05) gene expression. CRM or CRV alone did not change adipose tissue CB1 and FAAH gene expression. However, combined CRM and CRV (CRM+CRV) decreased abdominal adipose tissue FAAH gene expression (Δ = -0.37 ± 0.18, P < 0.05). The changes in gluteal CB1 and abdominal FAAH gene expression levels in the CR alone and the CRM+CRV group were different (P < 0.05) or tended to be different (P = 0.10).


CONCLUSIONS
There are depot differences in subcutaneous adipose tissue endocannabinoid system gene expression in obese individuals. Aerobic exercise training may preferentially modulate abdominal adipose tissue endocannabinoid-related gene expression during dietary weight loss.
Department of Exercise and Health Sciences, University of Massachusetts Boston, Boston, MA 02125, USA. tongjian.you@umb.edu
Tongjian
T
You
Beth L
BL
Disanzo
Xuewen
X
Wang
Rongze
R
Yang
Dawei
D
Gong
D000368:Aged; D000581:Amidohydrolases / Q000235:genetics / Q000378:metabolism*; D015992:Body Mass Index; D002081:Buttocks; D063385:Cannabinoid Receptor Modulators / Q000502:physiology; D015331:Cohort Studies; D004038:Diet, Reducing; D063388:Endocannabinoids; D015444:Exercise; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D008875:Middle Aged; D009765:Obesity / Q000178:diet therapy / Q000378:metabolism / Q000628:therapy; D050177:Overweight / Q000178:diet therapy / Q000378:metabolism / Q000628:therapy*; D005082:Physical Exertion; D012333:RNA, Messenger / Q000378:metabolism; D043884:Receptor, Cannabinoid, CB1 / Q000235:genetics / Q000378:metabolism*; D050151:Subcutaneous Fat / Q000378:metabolism*; D050507:Subcutaneous Fat, Abdominal / Q000378:metabolism*; D015431:Weight Loss; D000099252:Fatty Acid Amide Hydrolases
D000581:Amidohydrolases; D063385:Cannabinoid Receptor Modulators; D063388:Endocannabinoids; D012333:RNA, Messenger; D043884:Receptor, Cannabinoid, CB1; D000099252:Fatty Acid Amide Hydrolases