Minocci A, Savia G, Lucantoni R, Berselli M E, Tagliaferri M, Calò G, Petroni M L, de Medici C, Viberti G C, Liuzzi A
Division of Endocrinology and Metabolic Diseases, Ospedale San Giuseppe IRCCS, Istituto Auxologico Italiano, Verbania, Italy.
Int J Obes Relat Metab Disord. 2000 Sep;24(9):1139-44. doi: 10.1038/sj.ijo.0801385.
To evaluate whether fat distribution plays a role in determining serum leptin concentrations.
One-hundred and forty-seven obese patients, 77 males and 70 females, aged 45.1 +/- 13.2 y (mean +/- s.d.; range 21-73 y), with body mass index (BMI) ranging from 30 to 55 kg/m2 (mean 42.3 +/- 5.9). Ultrasound assessment of the thickness of subcutaneous and preperitoneal fat was carried out and calculation of their ratio as abdominal fat index (AFI), waist-hip ratio (WHR), body composition by bioelectrical impedance to evaluate the percentage of fat mass (FM%) and total amount of fat (FMKg) were also determined. Plasma leptin was measured by radio immuno assay (RIA).
In the whole group of patients, serum leptin concentrations were 37.2 +/- 18.4 ng/ml (range 6-101.3 ng/ml); in spite of BMI values not being significantly different, women had leptin values significantly higher (47.4 +/- 17.4 ng/ml) (P < 0.01) than males (28.1 +/- 15.1 ng/ml), also after correction for fat mass. The mean thickness of abdominal subcutaneous fat was 33.7 +/- 12.9 mm and it was significantly (P < 0.001) higher in female (40.9 +/- 10.6 mm) than in male (27.1 +/- 11.2 mm) patients; preperitoneal thickness was 22.9 +/- 7.1 mm, with significantly (P < 0.05) higher values in males (24.2 +/- 6.8 mm) than in females (21.7 +/- 7.3 mm). Accordingly, AFI (in all patients 0.84 +/- 0.6) was significantly higher in males (1.09 +/- 0.6) than in females (0.56 +/- 0.2). In the overall population, leptin concentrations were directly and significantly related to subcutaneous but not preperitoneal fat; they showed a strong inverse relationship with AFI and WHR. When the results were evaluated dividing the patients according to gender, subcutaneous fat thickness showed a stronger association with leptin levels in males than in females, whereas no association was found with preperitoneal fat thickness. Leptin and AFI values were significantly related only in men. WHR values were not correlated with leptin concentrations in either sex. When fat mass was added to the model, subcutaneous fat thickness, AFI and WHR remained independently associated with leptin concentrations. Age and diabetes did not influence these measures.
Fat distribution contributes to the variability in serum leptin in obese patients. In particular, subcutaneous abdominal fat is a determinant of leptin concentration, also independently of the amount of fat mass, whereas the contribution of preperitoneal visceral fat is not significant.
评估脂肪分布在决定血清瘦素浓度方面是否起作用。
147例肥胖患者，男性77例，女性70例，年龄45.1±13.2岁（均值±标准差；范围21 - 73岁），体重指数（BMI）为30至55kg/m²（均值42.3±5.9）。采用超声评估皮下及腹膜前脂肪厚度，并计算其比值作为腹部脂肪指数（AFI），同时测定腰臀比（WHR），通过生物电阻抗法评估身体成分以确定脂肪量百分比（FM%）和脂肪总量（FMKg）。采用放射免疫分析法（RIA）测定血浆瘦素。
在整个患者组中，血清瘦素浓度为37.2±18.4ng/ml（范围6 - 101.3ng/ml）；尽管BMI值无显著差异，但女性瘦素值（47.4±17.4ng/ml）经脂肪量校正后仍显著高于男性（28.1±15.1ng/ml）（P<0.01）。腹部皮下脂肪平均厚度为33.7±12.9mm，女性患者（40.9±10.6mm）显著高于男性患者（27.1±11.2mm）（P<0.001）；腹膜前脂肪厚度为22.9±7.1mm，男性（24.2±6.8mm）显著高于女性（21.7±7.3mm）（P<0.05）。相应地，AFI（所有患者为0.84±0.6）男性（1.09±0.6）显著高于女性（0.56±0.2）。在总体人群中，瘦素浓度与皮下脂肪直接且显著相关，但与腹膜前脂肪无关；与AFI和WHR呈强烈负相关。按性别对患者结果进行评估时，皮下脂肪厚度与瘦素水平在男性中的关联强于女性，而与腹膜前脂肪厚度无关联。瘦素与AFI值仅在男性中显著相关。WHR值在两性中均与瘦素浓度无相关性。当将脂肪量纳入模型时，皮下脂肪厚度、AFI和WHR仍与瘦素浓度独立相关。年龄和糖尿病不影响这些指标。
脂肪分布导致肥胖患者血清瘦素的变异性。特别是腹部皮下脂肪是瘦素浓度的决定因素，且独立于脂肪量，而腹膜前内脏脂肪的作用不显著。
