The relationship of abdominal fat mass assessed by helical or conventional computed tomography to serum leptin concentration.

In the present study, we focused on the relationship of intra-abdominal visceral fat (VF) or subcutaneous fat (SF) mass to serum leptin levels, and also on the relationship of leptin to serum lipid and lipoprotein concentration. Subjects with obesity (26 men, 26 women) were recruited for this study. We obtained helical CT scans with a tube current of 150 mA, voltage of 120 kV and 2:1 pitch (table speed in relation to slice thickness), starting at the upper edge of the liver and continuing to the pelvis. The intra-abdominal visceral fat (VF) volume was measured by drawing a line within the muscle wall surrounding the abdominal cavity. The abdominal SF volume was calculated by subtracting the VF volume from the total abdominal fat volume. By comparison, the abdominal VF and SF areas were determined at the umbilical level by the established slice-by-slice CT scanning technique. We found: 1) abdominal SF mass, either as volume or area, was a more important determinant of serum leptin than was VF mass; 2) among TC, TG, HDL-C and LDL-C, only TG had a positive correlation to serum leptin levels in men, whereas in women no lipid parameters had any relationship with leptin; and 3) VF mass had a positive correlation to serum TC and TG in men, whereas SF did not. The present study provides considerable evidence on the relationship between abdominal fat mass and serum leptin, and shows that the relationships between serum leptin and serum lipids and lipoproteins are not straightforward. We also suggest that fat area measured by conventional CT is a better indicator than its corresponding volume assessed by helical CT, based on the present results showing its closer association to serum lipids.

Gender differences in the effect of type 2 diabetes on serum lipids, pre-heparin plasma lipoprotein lipase mass and other metabolic parameters in Japanese population.

DESIGN: Cross-sectional study of fasting serum lipid and lipoprotein levels, pre-heparin lipoprotein lipase (LPL) mass, several other metabolic parameters, and intra-abdominal fat areas in 26 Japanese poorly controlled type 2 diabetic men and 23 women when matched for age, body mass index (BMI), and HbA1c between genders. SUBJECTS: Study subjects were Japanese type 2 diabetic patients who were admitted to our hospital between Jun 2001 and Aug 2002 because of their poorly controlled diabetes. A total of 49 subjects [40-79 years of age, average age 61.5 +/- 8.7; mean BMI 23.2 +/- 3.7 kg/m2] with fasting plasma glucose (PG) and HbA1c levels being 251 +/- 76.5 mg/dl and 10.8 +/- 2.2%, respectively, were involved in this study. METHODS: Pre-heparin LPL mass was determined by enzyme linked immunosorbent assay. Remnant like particle cholesterol (RLP-C) level was measured using an immunoaffinity mixed gel containing anti-apolipoprotein (apo) A-I and anti-apo B monoclonal antibodies. Serum leptin level was determined by radioimmunoassay. Intra-abdominal fat area was determined by computerized tomography analysis at the umbilical level. RESULTS: The men group showed a higher serum triglycerides (TG) and RLP-C levels, and lower high density lipoprotein-cholesterol levels and pre-heparin plasma LPL mass than did women. Serum leptin level was higher in women than in men counterparts. The intra-abdominal subcutaneous fat areas were significantly larger in women than in men counterparts, whereas the visceral fat areas did not differ. CONCLUSION: In Japanese population, poorly controlled type 2 diabetic men had more unfavorable lipid profile than did women counterparts, which may be associated with decreased lipolysis of plasma TG-rich lipoproteins by LPL.

Clinical features of a young Japanese woman having marked obesity and abrupt onset of diabetes mellitus with ketoacidosis.

The subject was a 26-year-old Japanese woman of 148 cm height, 96.2 kg of body weight (BW) (body mass index (BMI) of 43.8 kg/m(2)). She was referred to our hospital on May 1, 2000 for the evaluation of marked hyperglycemia with clinical symptom of general malaise, polydipsia, and ketonuria (3+). She did not smoke, or drink alcohol. But, she tended to eat lots of sweet food every day before the onset of this symptom. Her father was diagnosed type 2 diabetes mellitus. Her fasting plasma glucose and HbA(1c), and serum C-peptide were 398 mg/dl, 7.8% and less than 0.05 ng/ml [normal range: 0.94-2.8], respectively. She tested negative for anti-glutamic acid decarboxylase (GAD) antibodies and islet-cell antibodies. C-peptide level in her urine was as low as 3.4 microg/day. We immediately started insulin treatment under the diagnosis of abrupt onset of diabetes mellitus with diabetic ketoacidosis on the day of her admission, and the insulin treatment was continued after her being discharged. She showed continuous BW reduction until her BW reached approximately 60 kg, followed by her BW being plateau. During the period, intra-abdominal visceral fat (VF) and subcutaneous fat (SF) volume assessed by helical computerized tomography (CT) showed a substantial reduction [3.9-0.5 l for VF, 19-3.2 l for SF volume]. Pre-heparin plasma lipoprotein lipase (LPL) mass showed a considerably lower value when she had continuous BW reduction than did it when her BW reduction discontinued. These findings suggest that in this subject, continuous BW reduction after the abrupt onset of diabetes is closely associated with intra-abdominal fat mass reduction, which may be related to decreased production of LPL.