Liebmann P M, Reibnegger G, Lehofer M, Moser M, Pürstner P, Mangge H, Schauenstein K
Department of General and Experimental Pathology, University of Graz, Austria.
Int Immunol. 1998 Sep;10(9):1393-6. doi: 10.1093/intimm/10.9.1393.
Circadian alterations of several immune functions in vivo are well established, and may have important physiological and clinical implications. In line with this, tumor necrosis factor (TNF)-alpha has been implicated in the circadian regulation of body temperature. As soluble TNF receptors (TNF-R) act as naturally occurring competitive inhibitors of this cytokine, we investigated plasma levels of the soluble sTNF-R55 and sTNF-R75 in comparison with plasma cortisol and body temperature in nine healthy male volunteers during a defined 16 h light/8 h dark cycle. It was found that sTNF-R75, but not sTNF-R55, exhibited a clear-cut circadian rhythm with a significant (P < 0.01) peak at 7:51 a.m. +/- 58 min. The phase of the sTNF-R75 rhythm preceded that of cortisol by approximately 1 h and inversely corresponded to the circadian rhythm of body temperature. Moreover, the individual amplitudes of sTNF-R75 and body temperature exhibited a significant (P < 0.01) positive correlation. These results suggest that (i) the two sTNF-R are regulated independently, (ii) the sTNF-R75 rhythm is not primarily due to the cortisol rhythm and (iii) the fluctuation of the sTNF-R may contribute to the regulation of body temperature by modulating the availability of free TNF.
体内多种免疫功能的昼夜节律变化已得到充分证实，且可能具有重要的生理和临床意义。与此相符的是，肿瘤坏死因子（TNF）-α参与了体温的昼夜调节。由于可溶性TNF受体（TNF-R）作为这种细胞因子的天然竞争性抑制剂，我们在9名健康男性志愿者的16小时光照/8小时黑暗周期中，研究了可溶性sTNF-R55和sTNF-R75的血浆水平，并与血浆皮质醇和体温进行了比较。结果发现，sTNF-R75而非sTNF-R55呈现出明显的昼夜节律，在上午7:51±58分钟出现显著（P<0.01）峰值。sTNF-R75节律的相位比皮质醇提前约1小时，且与体温的昼夜节律相反。此外，sTNF-R75和体温的个体振幅呈现出显著（P<0.01）的正相关。这些结果表明：（i）两种sTNF-R是独立调节的；（ii）sTNF-R75节律并非主要由皮质醇节律引起；（iii）sTNF-R的波动可能通过调节游离TNF的可用性来参与体温调节。
