Ethnic variation in the activity of lipid desaturases and their relationships with cardiovascular risk factors in control women and an at-risk group with previous gestational diabetes mellitus: a cross-sectional study.

Background: Lipid desaturase enzymes mediate the metabolism of fatty acids to long chain polyunsaturated fatty acids and their activities are related to metabolic risk factors for Type 2 diabetes (T2DM) and coronary heart disease (CHD). There are marked ethnic differences in risks of CHD and T2DM but little is known about ethnic differences in desaturase activities.

Methods: Samples from a study of CVD risk in women with previous gestational diabetes were analysed for percentage fatty acids in plasma free fatty acid, triglyceride, cholesterol ester and phospholipid pools for 89 white European, 53 African Caribbean and 56 Asian Indian women.

Early metabolic defects following gestational diabetes in three ethnic groups of anti-GAD antibodies negative women with normal fasting glucose.

Objective: To characterise early metabolic abnormalities and the impact of ethnicity following gestational diabetes mellitus (GDM).

Design: Women with a history of GDM belonging to three different ethnic groups were evaluated. Using the insulin-modified, frequently-sampled intravenous glucose tolerance test (FSIVGTT) and HOMA we studied 34 European, 16 South Asian and 10 Afro-Caribbean women with normal fasting glucose following GDM and 44 European, 16 South Asian and 19 Afro-Caribbean controls to assess insulin action and secretion.

Coronary calcification, homocysteine, C-reactive protein and the metabolic syndrome in Type 2 diabetes: the Prospective Evaluation of Diabetic Ischaemic Heart Disease by Coronary Tomography (PREDICT) Study.

Aims: The PREDICT Study aims to determine: (i) the association between cardiovascular risk factors and coronary artery calcification score (CACS) obtained by electron beam tomography and (ii) the predictive value of CACS for coronary heart disease (CHD) events in Type 2 diabetes.

Methods: Having previously reported relationships between CACS and conventional risk factors, we have now studied the novel risk factors, plasma high-sensitivity C-reactive protein (CRP) and homocysteine, insulin resistance, serum apoprotein A1 and B concentrations, the serum triglyceride/high-density lipoprotein cholesterol ratio and metabolic syndrome (International Diabetes Federation definition) in 573 subjects of the PREDICT Type 2 diabetes cohort.

Results: In univariate analyses, the only significant positive novel correlate of CACS was homocysteine (P = 0.

Sustained endogenous glucose production, diminished lipolysis and non-esterified fatty acid appearance and oxidation in non-obese women at high risk of type 2 diabetes.

Objective: To evaluate early defects in glucose production, lipolysis and fatty acid oxidation in non-obese, normally glucose tolerant women, who are nevertheless at risk of type 2 diabetes.

Methods: Ten women with previous gestational diabetes (pGDM) and ten controls were studied in two 4 h infusions of stable isotopes 6,6-(2)H(2)-glucose, 1-(13)C-palmitate, and 1,1,2,3,3-(2)H(5)-glycerol with and without infusion of adrenaline. Fatty acid oxidation was quantified using indirect calorimetry and (13)CO(2) measurements.

The impact of ethnicity on glucose regulation and the metabolic syndrome following gestational diabetes.

Aims/hypothesis: We assessed the impact of ethnic origin on metabolism in women following gestational diabetes mellitus (GDM).

Materials And Methods: Glucose regulation and other features of the metabolic syndrome were studied at 20.0 (18.

Impaired circulating glucagon-like peptide-1 response to oral glucose in women with previous gestational diabetes.

Background And Objective: Women with previous gestational diabetes (pGDM) are at risk of developing Type 2 diabetes. Glucagon-like peptide-1 (GLP-1) potentiates the insulin response to oral glucose, and its secretion is diminished in Type 2 diabetes. The aim of the study was to see if decreased GLP-1 secretion might be an early abnormality in the progression to Type 2 diabetes and would therefore be diminished in women with pGDM.

Insulin resistance and beta-cell dysfunction in normoglycaemic European women with a history of gestational diabetes.

Objective: Women with previous gestational diabetes (GDM) are at increased risk of subsequent type 2 diabetes. To characterize early metabolic abnormalities associated with this increased risk, we studied normoglycaemic women with a history of GDM.

Patients And Measurements: We performed an insulin-modified, frequently sampled intravenous glucose tolerance test (FSIVGTT) in 34 normoglycaemic European women with previous GDM and 44 European control women, deriving measures of insulin sensitivity, glucose effectiveness, glucose disappearance rate and acute insulin response to glucose.

Relation between insulin kinetics and insulin sensitivity in pregnancy.

Background: Different time-concentration profiles of plasma insulin following insulin modification of a frequently sampled intravenous glucose-tolerance-test (FSIVGTT) were observed in a study investigating maternal metabolism and fetal macrosomia. We aimed to investigate whether these differences were related to the volume of distribution of insulin, insulin clearance, or both.

Design: Forty-four women were studied between 33 and 35 weeks' gestation using an insulin-modified FSIVGTT.

Delayed metabolic and thermogenic response to a mixed meal in normoglycemic European women with previous gestational diabetes.

We assessed postprandial thermogenesis (PPT) for 3 h following a mixed meal in 29 normoglycemic European women with previous gestational diabetes (GDM), compared with 37 control women. Given the potential role of catecholamines and insulin in the regulation of PPT, we assessed insulin and catecholamine responses to the meal. There was no significant difference between the two groups in resting energy expenditure, PPT (although lower in the GDM group), or catecholamine levels.

Prevalence and features of pancreatic islet cell autoimmunity in women with gestational diabetes from different ethnic groups.

Objective: To assess the prevalence and characteristics of islet cell autoimmunity amongst women with gestational diabetes selected from South Asian and Afro-Caribbean as well as European populations.

Design: Cross-sectional retrospective survey of subject cohort.

Population: Three hundred and twenty-one women with a recent history of gestational diabetes (173 European, 86 South Asian and 62 Afro-Caribbean), a median (range) of 22 (1-150) months postpartum.

Smoking is associated with increased hepatic lipase activity, insulin resistance, dyslipidaemia and early atherosclerosis in Type 2 diabetes.

We have studied the relationships between hepatic lipase activity, smoking, dyslipidaemia insulin resistance, and early atherosclerosis in 67 Type 2 diabetic subjects, 47 non-smokers and 20 smokers. Insulin resistance was measured using an insulin modified frequently sampled intravenous glucose tolerance test. Early atherosclerosis was assessed using high-resolution ultrasound to measure carotid intima media thickness (IMT) and an arterial ultrasonic score (AUS).

Insulin resistance, cardiovascular risk factors and ultrasonically measured early arterial disease in normotensive Type 2 diabetic subjects.

Background: The objective of the study was to examine the relationship between serum fasting insulin, insulin sensitivity S(i), cardiovascular risk factors, and asymptomatic early atherosclerosis in normotensive Type 2 diabetic subjects.

Methods: Specific insulin was measured using an enzyme-linked immunosorbent assay (ELISA) and insulin sensitivity was assessed with an insulin-modified frequently sampled intravenous glucose tolerance test (FSIVGTT). Early atherosclerotic change was assessed using carotid intima media thickness (IMT) and an arterial ultrasound score (AUS) measured by high-resolution B-mode ultrasound.

Effects of 7 years of growth hormone replacement therapy in hypopituitary adults.

Short-term studies of GH replacement in adult hypopituitarism have usually demonstrated beneficial effects on body composition and circulating lipids, with neutral or occasionally adverse effects on glucose tolerance. Fasting hyperinsulinemia has been reported. GH effects on cardiac function have been variable.

The effects of growth hormone replacement therapy on overnight metabolic fuels in hypopituitary patients.

Objective: Hypopituitary adults on conventional replacement have low concentrations of metabolic fuels throughout the night, possibly related to GH deficiency or to decreased cortisol levels overnight. We investigated whether GH replacement corrects the overnight fuel deficiency.

Design: We measured circulating levels of metabolic fuels: glucose, non-esterified fatty acids (NEFA), glycerol and 3-hydroxybutyrate (3-OHB) and insulin concentrations over 24 h (from 0730 h to 0700 h) in hypopituitary adults before and after GH treatment in a randomized double-blind placebo-controlled trial of 3 months' duration.

Effects of four years' treatment with biosynthetic human growth hormone (GH) on glucose homeostasis, insulin secretion and lipid metabolism in GH-deficient adults.

Objective: To study the effects of long-term growth hormone (GH) treatment on lipid metabolism and carbohydrate tolerance in GH-deficient adults.

Design: Open trial of GH treatment for 4 years. GH dose was (median, range) 0.

Elevated leptin concentrations in growth hormone-deficient hypopituitary adults.

Background: Hypopituitarism with growth hormone (GH) deficiency is associated with obesity characterized by central (abdominal) distribution of fat. Recent work has demonstrated that leptin, a product of obese gene, is raised in obesity.

Objective: To study circulating leptin levels in GH-deficient hypopituitary adults and to investigate its anthropometric, gender and metabolic relations.

Overnight metabolic fuel deficiency in patients treated conventionally for hypopituitarism.

Background: Hormone replacement in hypopituitary adults attempts to reproduce normal physiology. Conventional regimens fail to mimic normal hormone profiles over 24 hours.

Objective: To investigate the metabolic consequences of conventional hormone replacement in hypopituitary adults by measuring circulating levels of the major fuels, glucose, non-esterified fatty acids (NEFA), glycerol and 3-hydroxybutyrate (3-OHB) over 24 hours in hypopituitary subjects and controls.

Relative fasting hypoinsulinaemia and ultrasonically measured early arterial disease in type 2 diabetes. The SENDCAP Study Group, St. Mary's, Ealing, Northwick Park Diabetes Cardiovascular Disease Prevention Study.

Macrovasular disease is the most important cause of morbidity and mortality in Type 2 (non-insulin-dependent) diabetes. Dyslipidaemia and hyperinsulinaemia have been proposed as aetiological factors. This paper describes the interrelationships between fasting serum insulin, serum lipids, and the extent of ultrasonically measured early arterial disease in Type 2 diabetic subjects screened for entry into a prospective study set up to ascertain whether improving serum lipids can alter the progress of arterial disease in Type 2 diabetes.

Diurnal variation of sex hormone binding globulin and insulin-like growth factor binding protein-1 in women with polycystic ovary syndrome.

Objectives: The aim of this study was to examine (1) the diurnal variation in SHBG and (2) the inter-relationships of insulin, IGF-I, SHBG and IGFBP-1 over 24 hours in 10 women with anovulatory PCOS and compare them with weight-matched ovulatory controls.

Patients And Methods: The two groups comprised 10 anovulatory women with PCOS (as defined by clinical, ultrasound and biochemical criteria) and 10 weight matched controls. Serum samples were taken at two-hourly intervals for 24 hours and stored for measurement of SHBG, IGFBP-1, insulin and IGF-I.

The effects of short and long-term growth hormone replacement therapy in hypopituitary adults on lipid metabolism and carbohydrate tolerance.

The effects of replacement with biosynthetic human GH on carbohydrate tolerance and lipid metabolism were studied in 40 hypopituitary adults during a randomized double blind, placebo-controlled trial for 6 months, followed by a 12-month open trial. The daily GH dose was 0.04 +/- 0.

Replacement treatment with biosynthetic human growth hormone in growth hormone-deficient hypopituitary adults.

Objectives: The physiological role of growth hormone in adult life has recently attracted increased interest. We have studied the clinical effects and the effects on body composition of prolonged replacement with biosynthetic human GH in a large number of hypopituitary adults.

Design: A randomized double blind placebo controlled trial for 6 months followed by an open trial of GH treatment for 12 months.

Insulin resistance with respect to lipolysis in non-diabetic relatives of European patients with type 2 diabetes.

Type 2 diabetes is characterized by resistance to insulin action of glucose metabolism and lipolysis. First-degree relatives of diabetic patients are at increased risk of developing diabetes themselves and early metabolic abnormalities in these relatives may represent primary defects in the pathogenesis of diabetes. Our previous work has demonstrated impaired suppression of lipolysis after an oral glucose load in glucose-tolerant relatives of Asian origin, but not in European relatives.

Reduced postprandial energy expenditure in women predisposed to type 2 diabetes.

Type 2 (non-insulin dependent) diabetes is so common that it has been hypothesized that in the course of evolution the predisposition to it may have conferred some advantage, before or during the reproductive years. It is frequently preceded by gestational diabetes. In order to test the basis for the hypothetical advantage, energy expenditure was investigated in 10 women with documented transient diabetes in a previous pregnancy.