Premenopausal Advantages in Postprandial Lipid Metabolism Are Lost in Women With Type 2 Diabetes

Premenopausal Advantages in Postprandial Lipid Metabolism Are Lost in Women With Type 2 Diabetes Michael G. Masding , MBBS, MRCP 1 2 , Anna J. Stears , MBBS, MRCP 1 2 , Graham C. Burdge , PHD 2 , Stephen A. Wootton , PHD 2 and Derek D. Sandeman , BSC, MBBS, FRCP 1 1 Southampton University Hospitals NHS Trust, Southampton, U.K 2 Institute of Human Nutrition, University of Southampton, Southampton, U.K Address correspondence and reprint requests to Dr. Mike Masding, Specialist Registrar in Diabetes & Endocrinology, Poole Hospital NHS Trust, Longfleet Road, Poole BH15 2JB, U.K. E-mail: mike.mas{at}lineone.net Abstract OBJECTIVE —Women with type 2 diabetes appear to lose the protection against cardiovascular disease afforded by estrogens. We examined the effects of menopausal status on postprandial clearance of dietary fat in healthy and diabetic women. RESEARCH DESIGN AND METHODS —Fasting subjects (premenopausal and postmenopausal control subjects, premenopausal and postmenopausal diabetic women, all n = 8) were given a meal containing the stable isotope 1,1,1- 13 C-tripalmitin, with blood and breath sampled for 6 and 24 h, respectively, in the postprandial period. Lower levels of 13 C-palmitic acid ( 13 C-PA) in the triglyceride fraction implies more efficient chylomicron clearance, lower levels of 13 C-PA in the nonesterified fatty acid (NEFA) fraction implies improved dietary NEFA entrapment, and higher levels of 13 CO 2 in the breath denote more efficient of oxidation of dietary-derived lipid. RESULTS —In diabetic women, there were no differences between the pre- and postmenopausal groups for any of these parameters. In contrast, premenopausal control subjects, compared with postmenopausal control subjects, had lower 13 C-PA in the triglyceride fraction area under the curve (AUC) (premenopausal median [range] 25.2 [12.1–49.4 mmol/l] per 6 h, postmenopausal 48.5 [15.5–77.2 mmol/l] per 6 h; P < 0.01) and higher 13 CO 2 levels in the breath AUC (premenopausal 22.5 [18.0–31.5%] of administered dose, postmenopausal 17.2 [11.2–31.5%] of administered dose; P < 0.01) with no difference between groups in levels of 13 C-PA in the NEFA fraction AUC. CONCLUSIONS —The premenopausal advantage in clearance of dietary lipid is not seen in premenopausal diabetic women. This is likely to promote an atherogenic lipoprotein profile and may contribute to the loss of cardiovascular disease protection seen in diabetic women. AUC, area under the curve CHD, coronary heart disease