Centre for Nutrition, Exercise and Metabolism (CNEM), Department for Health, University of Bath, Bath, BA2 7AY, UK.
Department of Systems Biology, Harvard Medical School, Boston, MA, MA02115, USA.
Int J Obes (Lond). 2024 Jul;48(7):993-1002. doi: 10.1038/s41366-024-01513-7. Epub 2024 Mar 27.
T-Lymphocyte activation is modulated by the adipokine leptin and serum concentrations of this hormone can be reduced with short-term calorie restriction. The aim of this study was to understand whether leptin per se is important in determining levels of T-lymphocyte activation in humans, by investigating whether the reduction in leptin concentration following calorie restriction is associated with a decrease in T-Lymphocyte activation in blood and adipose tissue.
Twelve men with overweight and obesity (age 35-55 years, waist circumference 95-115 cm) reduced their calorie intake by 50% for 3 consecutive days. Blood and subcutaneous adipose tissue were obtained for isolation of immune cells and cytokine analysis. CD4+ and CD8 + T-Lymphocytes were identified and characterised according to their expression of activation markers CD25 and CD69 by flow cytometry.
Serum leptin was reduced by (mean ± SEM) 31 ± 16% (p < 0.001) following calorie restriction. The percentage of blood CD4 + CD25 + T-lymphocytes and level of CD25 expression on these lymphocytes were significantly reduced by 8 ± 10% (p = 0.016) and 8 ± 4% (p = 0.058), respectively. After calorie restriction, ex vivo leptin secretion from abdominal subcutaneous adipose tissue explants was not changed, and this corresponded with a lack of change in adipose tissue resident T-Lymphocyte activation.
Serum leptin was reduced after calorie restriction and this was temporally associated with a reduction in activation of blood CD4 + CD25 + T-Lymphocytes. In abdominal subcutaneous adipose tissue, however, leptin secretion was unaltered, and there were no observed changes in adipose resident T-Lymphocyte activation.
T 淋巴细胞的激活受到脂肪因子瘦素的调节，而这种激素的血清浓度可以通过短期热量限制来降低。本研究的目的是通过研究热量限制后瘦素浓度的降低是否与血液和脂肪组织中 T 淋巴细胞激活的减少有关，来了解瘦素本身是否对人类 T 淋巴细胞激活水平的决定很重要。
12 名超重和肥胖的男性（年龄 35-55 岁，腰围 95-115cm）连续 3 天减少 50%的热量摄入。采集血液和皮下脂肪组织，用于分离免疫细胞和细胞因子分析。通过流式细胞术根据激活标志物 CD25 和 CD69 的表达来鉴定和描述 CD4+和 CD8+T 淋巴细胞。
热量限制后，血清瘦素降低（平均值±SEM 为 31±16%，p<0.001）。血液中 CD4+CD25+T 淋巴细胞的百分比和这些淋巴细胞上 CD25 的表达水平分别显著降低了 8±10%（p=0.016）和 8±4%（p=0.058）。热量限制后，腹部皮下脂肪组织活检标本中离体的瘦素分泌没有改变，这与脂肪组织中驻留 T 淋巴细胞激活没有改变相对应。
热量限制后血清瘦素降低，与血液中 CD4+CD25+T 淋巴细胞的激活减少呈时间相关性。然而，在腹部皮下脂肪组织中，瘦素分泌没有改变，脂肪组织中驻留 T 淋巴细胞的激活也没有观察到变化。
