| First Author | Okamatsu-Ogura Y | Year | 2007 |
| Journal | Am J Physiol Endocrinol Metab | Volume | 292 |
| Issue | 4 | Pages | E1135-9 |
| PubMed ID | 17164436 | Mgi Jnum | J:120398 |
| Mgi Id | MGI:3706480 | Doi | 10.1152/ajpendo.00425.2006 |
| Citation | Okamatsu-Ogura Y, et al. (2007) Brown fat UCP1 is not involved in the febrile and thermogenic responses to IL-1beta in mice. Am J Physiol Endocrinol Metab 292(4):E1135-9 |
| abstractText | The activity of brown adipose tissue (BAT), a site of nonshivering metabolic thermogenesis, has been reported to increase after interleukin (IL)-1beta/lipopolysaccharide injection. To clarify the possible contribution of BAT thermogenesis to whole body febrile response, we investigated febrile and thermogenic response to IL-1beta using mice deficient in uncoupling protein-1 (UCP1), a key molecule for BAT thermogenesis. In wild-type (WT) mice, IL-1beta injection (5 mug/kg ip) increased body temperature (+1.82 degrees C at 20 min), decreased physical activity (-37% at 1 h), and produced a slight and insignificant rise (+15% at 1 h) in oxygen consumption (Vo(2)). Vo(2) dependent on metabolic thermogenesis (DeltaVo(2 thermogenesis)) calculated by correcting the effect of physical activity was increased after IL-1beta injection (726 +/- 200 ml.h(-1).kg(-1) at 1 h). Almost the same responses were observed in UCP1-deficient mice, showing 638 +/- 87 ml.h(-1).kg(-1) of DeltaVo(2 thermogenesis) at 1 h. In contrast, CL316,243, a selective activator of BAT thermogenesis, increased body temperature, decreased physical activity, and produced a significant rise in Vo(2) in WT mice, showing 1,229 +/- 35 ml.h(-1).kg(-1) of DeltaVo(2 thermogenesis) at 1 h. These changes were not observed in UCP1-deficient mice. These results, conflicting with a previously proposed idea of a role of BAT in fever, suggest a minor contribution of BAT thermogenesis to IL-1beta-induced fever. In support of this, we found no effect of IL-1beta on triglyceride content and UCP1 mRNA level in BAT, in contrast with apparent effects of CL316,243. |
