Zinc attenuation of GDP binding to brown adipocytes mitochondria in genetically obese (ob/ob) mice
- 48 Downloads
In this study, we investigate the in vitro effect of zinc addition on guanosine diphosphate (GDP) binding to mitochondria in brown adipocytes of genetically obese (ob/ob) mice. Interscapular brown adipocytes of male mice (obese; lean) at 4 and 12 wk of age were incubated with 0, 50, 100, or 200 μM zinc sulfate. Mitochondria were then isolated and their GDP binding capacities were measured. The GDP-binding capacities of ob/ob mice were lower than lean mice, with or without zinc addition, in both age groups (p<0.05). Zinc addition did not have any significant effect on GDP binding in lean mice. GDP binding decreased with increasing zinc addition in ob/ob mice, and this attenuation was more predominant in 12-wk old ob/ob mice. Moreover, we found that high magnesium addition (5 mM) increased GDP binding in lean mice, but this effect was not significant in ob/ob mice. This study reveals that brown adipose tissue thermogenesis in ob/ob mice could be greatly attenuated by zinc addition, suggesting that zinc may play a regulatory role in obesity.
Index EntriesZinc magnesium brown adipocytes GDP binding obesity ob/ob mice
Unable to display preview. Download preview PDF.
- 7.M. D. Chen, W. H. Lin, and P. Y. Lin, Zinc sulfate and thyroxine treatment on the obese patients,Chin. Med. J. 48, 210–216 (1991).Google Scholar
- 9.P. Y. Lin, S. J. Liou, M. D. Chen, V. Cheng, P. Alexander, and W. H. Lin, Effects of zinc supplementation on the plasma glucose level and insulin activity in genetically obese (ob/ob) mice,Int. J. Obesity 19 (Suppl. 2), 63 (1995).Google Scholar
- 21.Statistical Analysis System Institute Inc.,SAS User's Guide: Statistics, SAS Institute, Cary (1985).Google Scholar
- 22.M. K. Hambidge, C. E. Casey, and N. F. Krebs, Zinc, inTrace Elements in Human and Animal Nutrition, 5th ed., W. Mertz, ed., Academic, New York, pp. 1–137 (1986).Google Scholar
- 24.T. A. Link, and G. von Jagow, Zinc ions inhibit the Qp center of bovine heart mitochondrial bc1 complex by blocking a protonatable group,J. Biol. Chem. 270, 25,001–25,006 (1995).Google Scholar