Mattacks Christine A, Sadler Dawn, Pond Caroline M
Department of Biological Sciences, The Open University, Milton Keynes, UK.
J Anat. 2003 Jun;202(6):551-61. doi: 10.1046/j.1469-7580.2003.00188.x.
To test the hypothesis that chronic immune stimulation of a peripheral lymph node induces the formation of additional mature adipocytes in adjacent adipose tissue, one popliteal lymph node of large male rats was stimulated by local injection of 10 microg or 20 microg lipopolysaccharide three times a week for 6 weeks. Adipocyte volumes in sites defined by their anatomical relations to the stimulated and homologous unstimulated popliteal lymph nodes were measured, plus adipocyte complement of the popliteal depot, and the lipid and protein content of adipocytes and adipose stroma. The higher dose of lipopolysaccharide doubled the mass of the locally stimulated lymph node and the surrounding adipose tissue enlarged by the appearance of additional mature adipocytes. Similar but smaller changes were observed in the popliteal adipose depot of the unstimulated leg and in a nodeless depot. The lipid content of the adipocytes decreased and that of the stroma increased dose-dependently in all samples measured but the changes were consistently greater in the depot surrounding the stimulated lymph node. The protein content of both adipocytes and stroma increased in samples surrounding the stimulated node. We conclude that chronic immune stimulation of lymphoid tissues induces the formation of more adipocytes in the adjacent adipose tissue. These findings suggest a mechanism for the selective hypertrophy of lymphoid-containing adipose depots in the HIV-associated adipose redistribution syndrome.
为了验证外周淋巴结的慢性免疫刺激会诱导相邻脂肪组织中形成更多成熟脂肪细胞这一假说，对大型雄性大鼠的一侧腘淋巴结每周进行3次局部注射10微克或20微克脂多糖刺激，持续6周。测量了根据其与受刺激和同源未受刺激腘淋巴结的解剖关系所定义部位的脂肪细胞体积，以及腘窝脂肪库的脂肪细胞数量，还有脂肪细胞和脂肪基质的脂质及蛋白质含量。较高剂量的脂多糖使局部受刺激淋巴结的质量增加了一倍，周围脂肪组织因出现更多成熟脂肪细胞而增大。在未受刺激腿部的腘窝脂肪库以及无淋巴结的脂肪库中观察到了类似但程度较小的变化。在所测量的所有样本中，脂肪细胞的脂质含量降低，基质的脂质含量呈剂量依赖性增加，但受刺激淋巴结周围脂肪库中的变化始终更大。受刺激淋巴结周围样本中的脂肪细胞和基质的蛋白质含量均增加。我们得出结论，淋巴组织的慢性免疫刺激会诱导相邻脂肪组织中形成更多脂肪细胞。这些发现提示了一种机制，可解释在与HIV相关的脂肪重新分布综合征中含淋巴结脂肪库的选择性肥大。
