scholarly journals Adipose-tissue-specific increase in glyceraldehyde-3-phosphate dehydrogenase activity and mRNA amounts in suckling pre-obese Zucker rats. Effect of weaning

1989 ◽  
Vol 257 (3) ◽  
pp. 935-935
1988 ◽  
Vol 254 (2) ◽  
pp. 483-487 ◽  
Author(s):  
I Dugail ◽  
A Quignard-Boulange ◽  
R Bazin ◽  
X Le Liepvre ◽  
M Lavau

The regulation of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene expression was studied during the onset of obesity in the genetically obese (fa/fa) rat by determination of GAPDH activity and hybridizable mRNA amounts in adipose tissue and liver from suckling and weanling rats. GADPH activity remained low throughout the suckling period, and a burst of activity occurred after weaning in both lean and obese pups. As early as 7 days of age, adipose tissue from pre-obese rats displayed a significant increase in enzyme activity, whereas no difference could be detected in the liver. In both suckling (16 days of age) and weanling (30 days of age) obese rats a proportionate increase in GAPDH activity and mRNA amounts was observed in adipose tissue, but not in liver. It is concluded that the obese genotype influences GAPDH gene expression at a pretranslational level and in a tissue-specific manner. This phenomenon could partly contribute to the hyperactive fat accretion in the obese rat, since glycolysis is the major metabolic pathway for lipogenic substrates in adipose tissue.


2002 ◽  
Vol 282 (1) ◽  
pp. E59-E66 ◽  
Author(s):  
Isabelle Hainault ◽  
Guillaume Nebout ◽  
Sophie Turban ◽  
Bernadette Ardouin ◽  
Pascal Ferré ◽  
...  

We investigated angiotensinogen (AGT) expression in adipose tissue and liver of Zucker rats during the onset of obesity. The developmental pattern of AGT expression (protein and mRNA) in liver was similar in both genotypes. In inguinal adipose tissue, AGT cell content was similar in suckling and weaned pups in lean rats, whereas it continuously increased with age in obese rats. AGT amount in adipocytes was unaffected by the genotype until weaning. Thereafter, adipocytes from obese rats displayed a significant increase in AGT content that was strengthened with age. Compared with the cell content, the amount of secreted AGT over 24 h was higher, and a genotype effect was observed as early as 14 days of age. Using fat cell populations differing by size, we showed that this AGT oversecretion was not solely related to adipocyte hypertrophy. Our results demonstrate that the fa genotype exerts a control on the production of AGT in a tissue-specific manner, suggesting a local role of AGT in the overdevelopment of adipose tissue.


1992 ◽  
Vol 262 (1) ◽  
pp. R33-R38 ◽  
Author(s):  
J. R. Vasselli ◽  
J. A. Fiene ◽  
C. A. Maggio

In growing male obese Zucker rats, hyperphagia reaches a maximum or “breakpoint” and declines at an earlier age with high fat than with chow-type diets. A serial adipose tissue biopsy technique was used to correlate changes of retroperitoneal adipocyte size and feeding behavior in 5- to 7-wk-old male lean and obese rats fed laboratory chow or a 35% fat diet until 30 wk of age. Although chow-fed groups had significantly greater cumulative intake, fat-fed groups had significantly greater body weight gain, retroperitoneal depot weight, and adipocyte number. Mean adipocyte size increased continuously in chow-fed groups but decreased over weeks 20-30 in fat-fed groups, reflecting increased adipocyte number. In fat-fed obese rats, hyperphagia reached a breakpoint at 11 wk and disappeared by 13 wk. In chow-fed obese rats, hyperphagia reached a breakpoint at 15-16 wk and disappeared by 19 wk. Biopsy samples revealed that adipocyte size of fat-fed obese rats was already close to maximal at 10 wk (1.12 micrograms lipid), while that of chow-fed obese rats only approached maximal at 20 wk (0.81 microgram lipid). At these time points, lipoprotein lipase activity paralleled adipocyte size. These data indicate that the duration of the growing obese rat's hyperphagia coincides with adipocyte filling and suggest the existence of feeding stimulatory and inhibitory signals from adipose tissue.


Data in Brief ◽  
2020 ◽  
Vol 29 ◽  
pp. 105290 ◽  
Author(s):  
Matthew A. Tilley ◽  
Amanda S. Hatcher ◽  
Paul D. Chantler ◽  
Shinichi Asano

1995 ◽  
Vol 207 (2) ◽  
pp. 761-767 ◽  
Author(s):  
V. Rolland ◽  
X. Leliepvre ◽  
M.L. Houbiguian ◽  
M. Lavau ◽  
I. Dugail

1991 ◽  
Vol 261 (2) ◽  
pp. E246-E251 ◽  
Author(s):  
D. H. Bessesen ◽  
A. D. Robertson ◽  
R. H. Eckel

Lipoprotein lipase (LPL) activity and mRNA levels were measured in cardiac muscle and adipose tissue from lean, obese, and weight-stable reduced-obese Zucker rats, both fasted and 2 h after feeding. Fasting epididymal fat LPL activity was substantially higher in obese rats relative to lean rats [6.9 vs. 0.2 nmol free fatty acid (FFA).10(6) cells-1.min-1; P = 0.0001], and was higher still in reduced-obese rats (15.7 nmol FFA.10(6) cells-1.min-1; P = 0.002). Adipose tissue LPL increased with feeding in all three groups. In marked contrast, fasting cardiac muscle LPL was lower in obese rats relative to lean (28.8 vs. 38.5 nmol FFA.g-1.min-1; P = 0.0064) and was lower still in reduced-obese rats (14.5 nmol FFA.g-1.min-1; P = 0.0001). LPL mRNA levels increased in adipose tissue along with enzyme activity; however, the magnitude of the changes were relatively small, suggesting that the primary regulatory steps are posttranslational. Weight reduction studies were also carried out in Sprague-Dawley rats with similar results. These studies show that sustained weight reduction results in coordinate changes in tissue-specific LPL, favoring delivery of lipoprotein triglyceride fatty acids to adipose tissue relative to cardiac muscle and the restoration of energy stores.


2000 ◽  
pp. 71-78 ◽  
Author(s):  
A Gorla-Bajszczak ◽  
C Siegrist-Kaiser ◽  
O Boss ◽  
AG Burger ◽  
CA Meier

OBJECTIVE: Examination of the pattern of expression of peroxisome proliferator-activated receptor (PPAR) isoforms alpha and gamma in a model of obesity. DESIGN: Examination of adipose tissue and primary adipocyte cultures from lean and obese Zucker rats at different ages (28 days and 12 weeks). METHODS: mRNA levels were measured by RNase protection assay.RESULTS: The highest levels of PPARalpha and gamma mRNA were present in brown adipose tissue (BAT), followed by liver and white adipose tissue (WAT) for the alpha and gamma subtypes, respectively, at both ages examined. PPARalpha was expressed 100-fold higher in BAT compared with WAT, and PPARgamma mRNA levels were 2-fold higher in the WAT of obese compared with lean rats. PPARalpha and gamma expression was minimal in m. soleus, although higher levels of PPARgamma were found in the diaphragm. In marked contrast to the findings in vivo, virtually no PPARalpha mRNA could be detected in BAT cultures differentiated in vitro. CONCLUSION: PPARalpha and gamma are most highly expressed in BAT in vivo. However, PPARalpha is undetectable in brown adipose cells in vitro, suggesting that the expression of this receptor is induced by some external stimuli. In addition, the expression of PPARgamma was increased in WAT from young obese animals, compatible with an early adaptive phenomenon. Finally, the presence of PPARgamma mRNA is detectable only in particular muscles, such as the diaphragm, suggesting the possibility of an influence of fiber type on its expression, although exercise did not influence the expression of PPARgamma in other skeletal muscles.


1980 ◽  
Vol 239 (3) ◽  
pp. R337-R343 ◽  
Author(s):  
K. M. Milam ◽  
J. S. Stern ◽  
L. H. Storlien ◽  
R. E. Keesey

Obese and lean Zucker rats received bilateral electrolytic lesions of the lateral hypothalamus (LH) at 10 wk of age; control obese and lean rats were sham lesioned. After lesioning the body weights of both obese and lean animals were first reduced and then maintained until being killed (32 wk) at a stable percentage of the nonlesioned control levels (74.5 and 78.3%, respectively). Carcass analysis revealed that the adipose tissue mass was significantly lowered by LH lesions in both the obese and lean animals. Percent carcass fat of lesioned lean rats was less than that of controls (15.0 vs. 23.5%) due to the presence of slightly, but not significantly, smaller and fewer adipocytes. Though absolute levels of fat were likewise lowered in obese rats, their percent carcass fat remained at control levels (52.0 vs. 53.0%) due to equivalent decreases in other body compartments. In the lesioned rats the reduced levels of adipose tissue were associated with a significant reduction in adipocyte number; adipocyte size was unchanged. It is concluded that the lateral hypothalamus of obese Zucker rats participates in the regulation of body weight in the same manner as in lean rats. The differences noted in percent carcass fat between LH lesioned lean and obese Zucker rats are apparently related to the obese animal's known propensity to sequester energy in the form of lipid.


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