The response of serum apolipoprotein H to an oral fat load.
BACKGROUND
We tested the hypothesis that serum apolipoprotein H (apo H) concentration increases after an oral fat load. Such a study would give valuable insight into whether apo H was influenced by the postprandial state.


METHODS
Ten male subjects aged 24-48 years were fed 62.5 g of total fat (saturates 12 g, monounsaturates 35.3 g, polyunsaturates 12.5 g). Venous blood was sampled hourly for 5 h post-oral fat load.


RESULTS
No significant change in serum apo H concentration occurred following the oral fat load. However, serum apo H in the baseline samples correlated significantly with subject body mass index (r = 0.683, P < 0.05), body fat mass (r = 0.778, P < 0.01), lean body mass (r = 0.693, P < 0.05), serum triglyceride (r = 0.732, P < 0.02), serum insulin (r = 0.808, P < 0.01) and insulin resistance index (r = 0.794, P < 0.01). In stepwise multiple linear regression model, with serum apo A1, apo B, lipoprotein(a), total cholesterol, triglyceride, HDL-cholesterol, LDL-cholesterol, plasma glucose and insulin and apo H as the dependent variable, insulin remained in the model (r = 0.81, P < 0.01). Conversely, with body mass index, body fat mass, lean body mass and waist/hip ratio in the model and apo H as dependent variable, only body fat mass remained in the model (r = 0.78, P < 0.01).


CONCLUSIONS
Serum apo H may be involved in insulin resistance and relates to various indices of adipose tissue, including body fat mass. However, serum apo H concentrations do not significantly change postprandially.
Zahedi
R G
RG
Department of Diabetes, Endocrinology and Metabolic Medicine, St Thomas' Hospital, London.
Summers
L K M
LK
Lumb
P
P
Chik
G
G
Crook
M A
MA
D000328:Adult; D001161:Arteriosclerosis / Q000209:etiology / Q000378:metabolism; D004041:Dietary Fats / Q000008:administration & dosage* / Q000009:adverse effects; D006023:Glycoproteins / Q000097:blood*; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D050356:Lipid Metabolism; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D053482:beta 2-Glycoprotein I
D004041:Dietary Fats; D006023:Glycoproteins; D007328:Insulin; D053482:beta 2-Glycoprotein I