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Title: Exercise reduces adipose tissue via cannabinoid receptor type 1 which is regulated by peroxisome proliferator-activated receptor-{delta}

Abstract

Obesity is one major cardiovascular risk factor. We tested effects of endurance exercise on cannabinoid receptor type 1 (CB1) and peroxisome proliferator-activated receptor-{delta} (PPAR-{delta})-dependent pathways in adipose tissue. Male Wistar rats were randomly assigned to standard laboratory chow or a high-fat diet without and with regular endurance exercise. Exercise in rats on high-fat diet significantly reduced visceral fat mass, blood pressure, and adipocyte size (each p < 0.05). Adipocyte hypertrophy induced by high-fat diet was accompanied by increased CB1 expression in adipose tissue, whereas exercise significantly reduced CB1 expression (each p < 0.05). CB1 receptor expression and adipocyte differentiation were directly regulated by PPAR-{delta}. Adipocyte hypertrophy induced by high-fat diet was accompanied by reduced PPAR-{delta}. Furthermore, selective silencing of PPAR-{delta} by RNA interference in 3T3-L1-preadipocyte cells significantly increased CB1 expression from 1.00 {+-} 0.06 (n = 3) to 1.91 {+-} 0.06 (n = 3; p < 0.01) and increased adipocyte differentiation, whereas adenovirus-mediated overexpression of PPAR-{delta} significantly reduced CB1 expression to 0.39 {+-} 0.03 (n = 3; p < 0.01) and reduced adipocyte differentiation. In the presence of the CB1 antagonist rimonabant adipocyte differentiation in stimulated 3T3 L1 preadipocyte cells was significantly reduced. The study indicates that high-fat diet-induced hypertrophymore » of adipocytes is associated with increased CB1 receptor expression which is directly regulated by PPAR-{delta}. Both CB1 and PPAR-{delta} are intimately involved in therapeutic interventions against a most important cardiovascular risk factor.« less

Authors:
 [1];  [1];  [1];  [1];  [1];  [1];  [1];  [1];  [2];  [2];  [3]
  1. Center for Hypertension and Metabolic Diseases, Department of Hypertension and Endocrinology, Daping Hospital, Third Military Medical University, Chongqing 400042 (China)
  2. Charite Campus Benjamin Franklin, Berlin (Germany)
  3. Center for Hypertension and Metabolic Diseases, Department of Hypertension and Endocrinology, Daping Hospital, Third Military Medical University, Chongqing 400042 (China). E-mail: zhuzm@yahoo.com
Publication Date:
OSTI Identifier:
20979826
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biochemical and Biophysical Research Communications; Journal Volume: 354; Journal Issue: 2; Other Information: DOI: 10.1016/j.bbrc.2006.12.213; PII: S0006-291X(06)02888-9; Copyright (c) 2007 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; ADENOVIRUS; ADIPOSE TISSUE; BLOOD PRESSURE; DIET; EXERCISE; FATS; HAZARDS; HYPERTROPHY; METABOLIC DISEASES; RATS; RECEPTORS; RNA

Citation Formats

Yan Zhencheng, Liu Daoyan, Zhang Lili, Shen Chenyi, Ma Qunli, Cao Tingbing, Wang Lijuan, Nie Hai, Zidek, Walter, Tepel, Martin, and Zhu Zhiming. Exercise reduces adipose tissue via cannabinoid receptor type 1 which is regulated by peroxisome proliferator-activated receptor-{delta}. United States: N. p., 2007. Web.
Yan Zhencheng, Liu Daoyan, Zhang Lili, Shen Chenyi, Ma Qunli, Cao Tingbing, Wang Lijuan, Nie Hai, Zidek, Walter, Tepel, Martin, & Zhu Zhiming. Exercise reduces adipose tissue via cannabinoid receptor type 1 which is regulated by peroxisome proliferator-activated receptor-{delta}. United States.
Yan Zhencheng, Liu Daoyan, Zhang Lili, Shen Chenyi, Ma Qunli, Cao Tingbing, Wang Lijuan, Nie Hai, Zidek, Walter, Tepel, Martin, and Zhu Zhiming. Fri . "Exercise reduces adipose tissue via cannabinoid receptor type 1 which is regulated by peroxisome proliferator-activated receptor-{delta}". United States. doi:.
@article{osti_20979826,
title = {Exercise reduces adipose tissue via cannabinoid receptor type 1 which is regulated by peroxisome proliferator-activated receptor-{delta}},
author = {Yan Zhencheng and Liu Daoyan and Zhang Lili and Shen Chenyi and Ma Qunli and Cao Tingbing and Wang Lijuan and Nie Hai and Zidek, Walter and Tepel, Martin and Zhu Zhiming},
abstractNote = {Obesity is one major cardiovascular risk factor. We tested effects of endurance exercise on cannabinoid receptor type 1 (CB1) and peroxisome proliferator-activated receptor-{delta} (PPAR-{delta})-dependent pathways in adipose tissue. Male Wistar rats were randomly assigned to standard laboratory chow or a high-fat diet without and with regular endurance exercise. Exercise in rats on high-fat diet significantly reduced visceral fat mass, blood pressure, and adipocyte size (each p < 0.05). Adipocyte hypertrophy induced by high-fat diet was accompanied by increased CB1 expression in adipose tissue, whereas exercise significantly reduced CB1 expression (each p < 0.05). CB1 receptor expression and adipocyte differentiation were directly regulated by PPAR-{delta}. Adipocyte hypertrophy induced by high-fat diet was accompanied by reduced PPAR-{delta}. Furthermore, selective silencing of PPAR-{delta} by RNA interference in 3T3-L1-preadipocyte cells significantly increased CB1 expression from 1.00 {+-} 0.06 (n = 3) to 1.91 {+-} 0.06 (n = 3; p < 0.01) and increased adipocyte differentiation, whereas adenovirus-mediated overexpression of PPAR-{delta} significantly reduced CB1 expression to 0.39 {+-} 0.03 (n = 3; p < 0.01) and reduced adipocyte differentiation. In the presence of the CB1 antagonist rimonabant adipocyte differentiation in stimulated 3T3 L1 preadipocyte cells was significantly reduced. The study indicates that high-fat diet-induced hypertrophy of adipocytes is associated with increased CB1 receptor expression which is directly regulated by PPAR-{delta}. Both CB1 and PPAR-{delta} are intimately involved in therapeutic interventions against a most important cardiovascular risk factor.},
doi = {},
journal = {Biochemical and Biophysical Research Communications},
number = 2,
volume = 354,
place = {United States},
year = {Fri Mar 09 00:00:00 EST 2007},
month = {Fri Mar 09 00:00:00 EST 2007}
}
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