Insulin resistance is independently associated with postprandial alterations of triglyceride-rich lipoproteins in type 2 diabetes mellitus.
OBJECTIVE
To evaluate the role of insulin resistance in development of postprandial dyslipidemia in type 2 diabetic patients in an experimental setting in which these patients were compared with nondiabetic subjects at similar glucose and insulin blood levels.


RESULTS
Eight type 2 diabetic patients in optimal blood glucose control and 7 control subjects (aged 50.0+/-2.6 and 48.1+/-1.3 years; body mass index 28.3+/-1.2 and 25.6+/-1.1 kg/m2; fasting plasma triglycerides 1.12+/-0.13 and 0.87+/-0.08 mmol/L, respectively; mean+/-SEM; NS) consumed a mixed meal during an 8-hour hyperinsulinemic glycemic clamp. Mean blood glucose during clamp was approximately 7.8 mmol/L, and plasma insulin during the preprandial steady state was approximately 480 pmol/L in both groups, that differed for insulin sensitivity (M/I value lower in diabetic subjects [1.65+/-0.30 and 3.42+/-0.60; P<0.05]). Subjects with diabetes had higher postprandial levels of lipids and apolipoprotein B (apoB) in large very low-density lipoprotein (incremental area for triglycerides 1814+/-421 versus 549+/-153 micromol/Lx6 hours; P<0.05; cholesterol 694+/-167 versus 226+/-41 micromol/Lx6 hours; P<0.05; apoB-48 6.3+/-1.0 versus 2.6+/-0.7 mg/Lx6 hours; P<0.05; apoB-100 56.5+/-14.9 versus 26.2+/-11.0 mg/Lx6 hours; NS). Basal lipoprotein lipase (LPL) activity before and after meal was higher in diabetic subjects, whereas postheparin LPL activity 6 hours after the meal was similar.


CONCLUSIONS
Insulin resistance is also associated with postprandial lipoprotein abnormalities in type 2 diabetes after acute correction for hyperglycemia and hyperinsulinemia.
Department of Clinical and Experimental Medicine, Federico II University, Naples, Italy. annuzzi@unina.it
Giovanni
G
Annuzzi
Claudia
C
De Natale
Ciro
C
Iovine
Lidia
L
Patti
Lucrezia
L
Di Marino
Silvana
S
Coppola
Stefano
S
Del Prato
Gabriele
G
Riccardi
Angela A
AA
Rivellese
D001055:Apolipoproteins B / Q000097:blood; D001786:Blood Glucose; D002096:C-Peptide / Q000097:blood; D002914:Chylomicrons / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000201:enzymology / Q000378:metabolism*; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005260:Female; D005947:Glucose / Q000378:metabolism; D006801:Humans; D007262:Infusions, Intravenous / Q000379:methods; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000502:physiology*; D008049:Lipase / Q000097:blood; D008055:Lipids / Q000097:blood; D008071:Lipoprotein Lipase / Q000097:blood; D008074:Lipoproteins / Q000097:blood / Q000378:metabolism*; D008075:Lipoproteins, HDL / Q000097:blood; D053419:Lipoproteins, IDL; D008077:Lipoproteins, LDL / Q000097:blood; D008079:Lipoproteins, VLDL / Q000097:blood; D008297:Male; D008875:Middle Aged; D019518:Postprandial Period / Q000502:physiology*; D014280:Triglycerides / Q000097:blood / Q000378:metabolism*
D001055:Apolipoproteins B; D001786:Blood Glucose; D002096:C-Peptide; D002914:Chylomicrons; D005230:Fatty Acids, Nonesterified; D007328:Insulin; C504173:LIPC protein, human; D008055:Lipids; D008074:Lipoproteins; D008075:Lipoproteins, HDL; D053419:Lipoproteins, IDL; D008077:Lipoproteins, LDL; D008079:Lipoproteins, VLDL; D014280:Triglycerides; C030087:lipoprotein triglyceride; D008049:Lipase; D008071:Lipoprotein Lipase; D005947:Glucose