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Key summary points: Aim: Medical doctors making decisions without consulting their patients has gradually shifted towards shared decision making. Findings: Nevertheless, in this study from geriatric wards in Norway, only half of health care professionals (HCP) report that patient preferences were clarified, and the majority of HCP reported that they did not inform, involve, and treat patients based on patient preferences. Message: Measures are needed to improve integration of patient's preferences into decision-making. Purpose: We aimed to identify whether health care professionals (HCP) examine their patient and next-of-kin preferences, and to study whether medical decisions follow these preferences. Method: A cross-sectional web-based survey was conducted with multidisciplinary HCP from 12 geriatric wards in the South-Eastern Norway Regional Health Authority. Results: Of the 289 HCPs responding (response rate 61%), mean age 37.8 years (SD 11.3), 235 (81.3%) women, 12.4 (SD 9.6) years of experience and 67 (23.2%) medical doctors, only half report clarifying patients' preferences. The majority reported that they did not inform, involve and treat in line with such preferences. However, 53% believe that HCP, patients and next-of-kin should make clinical decisions together. Discussion: Our findings indicate a lack of engagement in conversation and inclusion of patient preferences when providing health interventions in geriatric wards. Measures for change of culture are needed. [ABSTRACT FROM AUTHOR]

Background/objectives: To investigate whether intake of whey protein and butter naturally enriched in medium-chain fatty acids (MC-SFAs) (C6-C12) affected body composition, insulin sensitivity, blood pressure (BP) and plasma cholesterol concentrations.Subjects/methods: A 12-week randomised, double-blinded, intervention study was completed in 52 abdominally obese adults. Subjects were assigned to one of four dietary supplementations: 63 g per day of milk fat with either high- (8.5 g per day) or low-MC-SFA (6.9 g per day) content combined with 60 g per day of whey or casein.We examined changes in the body composition by dual-energy X-ray absorption scan, insulin sensitivity using homoeostatic model assessment of insulin resistance (HOMA-IR) and Matsuda index, and diurnal BP and plasma cholesterol concentrations. Two-factor analysis of variance was used to examine the impact of MC-SFA content and protein type.Results: We observed that lean body mass increased by 981 g (95% confidence interval (CI): 248-1713; P=0.010) after high-MC-SFA compared with low-MC-SFA supplementation. Concomitantly, total body-fat percentage increased by 0.70 percentage points (95% CI: 0.10-1.31; P=0.024) after intake of low-MC-SFA butter compared with intake of high-MC-SFA butter. Both changes were independent of protein type (P=0.96 and P=0.99, respectively). We found no difference in HOMA-IR, Matsuda index, diurnal BP or plasma cholesterol concentrations related to MC-SFA content or protein type.Conclusions: Enhanced intake of MC-SFA increased the lean body mass and caused a significantly lower total body-fat percentage compared with lower intake of MC-SFA. Consequently, the composition of dairy fat should be considered when evaluating the impact of dairy products on body composition. [ABSTRACT FROM AUTHOR]

Background/Objectives:Subjects with type 2 diabetes (T2D) and their nondiabetic first-degree relatives (REL) have increased risk of cardiovascular disease (CVD). Postprandial triglyceridemia (PPL), influenced by diet, is an independent risk factor for CVD. Dietary fat elicits increased PPL in T2D compared with nondiabetic controls, but our knowledge of PPL responses to fat in REL is sparse. Our aim was to test the hypothesis that REL respond to a monounsaturated fatty acid (MUFA) challenge with a higher PPL response compared with controls who have no family history of T2D (CON) and that MUFAs exert a differential impact on incretin responses and on the expression of genes involved in carbohydrate and lipid metabolism in muscle and adipose tissues of REL and CON.Subjects/Methods:A total of 17 REL and 17 CON consumed a meal with 72 energy percent derived from MUFAs (macadamia nut oil). Plasma triglycerides, free fatty acids, insulin, glucose, glucagon-like peptide 1, glucose-dependent insulintropic peptide and ghrelin were measured at baseline and regular intervals until 4 h postprandially. Muscle and adipose tissue biopsies were collected at baseline and at 210 min after the meal.Results:The MUFA-rich meal did not elicit different responses (P>0.05) in PPL, insulin, glucose, incretins or ghrelin in REL and CON. Several genes were differentially regulated in muscle and adipose tissues of REL and CON.Conclusions:A MUFA-rich meal elicits similar PPL, insulin and incretin responses in REL and CON. MUFAs have a differential impact on gene expression in muscle and adipose tissues in a pattern pointing toward early defects in lipid metabolism in REL. [ABSTRACT FROM AUTHOR]

Background/objectives:Prospective studies have shown an inverse relationship between whole grain consumption and the risk of type 2 diabetes, where short chain fatty acids (SCFA) may be involved. Our objective was to determine the effect of isolated arabinoxylan alone or in combination with whole grain rye kernels on postprandial glucose, insulin, free fatty acids (FFA), gut hormones, SCFA and appetite in subjects with the metabolic syndrome (MetS).Subjects/methods:Fifteen subjects with MetS participated in this acute, randomised, cross-over study. The test meals each providing 50 g of digestible carbohydrate were as follows: semolina porridge added concentrated arabinoxylan (AX), rye kernels (RK) or concentrated arabinoxylan combined with rye kernels (AXRK) and semolina porridge as control (SE). A standard lunch was served 4 h after the test meals. Blood samples were drawn during a 6-h period, and appetite scores and breath hydrogen were assessed every 30 min.Results:The AXRK meal reduced the acute glucose (P=0.005) and insulin responses (P<0.001) and the feeling of hunger (P=0.005; 0-360 min) compared with the control meal. The AX and AXRK meals increased butyrate and acetate concentrations after 6 h. No significant differences were found for the second meal responses of glucose, insulin, FFA, glucagon-like peptide-1 or ghrelin.Conclusions:Our results indicate a stimulatory effect of arabinoxylan on butyrate and acetate production, however, with no detectable effect on the second meal glucose response. It remains to be tested in a long-term study if a beneficial effect on the glucose response of the isolated arabinoxylan will be related to the SCFA production. [ABSTRACT FROM AUTHOR]

Background/Objectives:Few studies have used biomarkers of whole-grain intake to study its relation to glucose metabolism. We aimed to investigate the association between plasma alkylresorcinols (AR), a biomarker of whole-grain rye and wheat intake, and glucose metabolism in individuals with metabolic syndrome (MetS).Subjects/Methods:Participants were 30-65 years of age, with body mass index 27-40 kg/m2 and had MetS without diabetes. Individuals were recruited through six centers in the Nordic countries and randomized to a healthy Nordic diet (ND, n=96), rich in whole-grain rye and wheat, or a control diet (n=70), for 18-24 weeks. In addition, associations between total plasma AR concentration and C17:0/C21:0 homolog ratio as an indication of the relative whole-grain rye intake, and glucose metabolism measures from oral glucose tolerance tests were investigated in pooled (ND+control) regression analyses at 18/24 weeks.Results:ND did not improve glucose metabolism compared with control diet, but the AR C17:0/C21:0 ratio was inversely associated with fasting insulin concentrations (P=0.002) and positively associated with the insulin sensitivity indices Matsuda ISI (P=0.026) and disposition index (P=0.022) in pooled analyses at 18/24 weeks, even after adjustment for confounders. The AR C17:0/C21:0 ratio was not significantly associated with insulin secretion indices. Total plasma AR concentration was not related to fasting plasma glucose or fasting insulin at 18/24 weeks.Conclusions:The AR C17:0/C21:0 ratio, an indicator of relative whole-grain rye intake, is associated with increased insulin sensitivity in a population with MetS. [ABSTRACT FROM AUTHOR]

BACKGROUND/OBJECTIVES: Several studies emphasise that arabinoxylan and β-glucan have more beneficial effects on glucose metabolism than low-dietary fibre (DF) meals. Less attention has been paid to the effects of concentrated DF compared with whole grain. We compared the effects of DF and whole grain on glucose, hormone responses and appetite in subjects with the metabolic syndrome (MetS). SUBJECTS/METHODS: Fifteen subjects with MetS participated in this acute, randomised, cross-over intervention study. The test breads provided 50 g of digestible carbohydrate: wheat bread with concentrated arabinoxylan (AX) or β-glucan (BG), rye bread with kernels (RK) and wheat bread (WB) as control. Blood samples were drawn for 270 min to determine glucose, insulin, glucagon-like peptide-1, glucose-dependent insulinotropic peptide (GIP) and ghrelin. Appetite score was addressed every 30 min. Ad libitum energy intake (EI) was measured 270 min after test meals. RESULTS: Compared with WB, BG and RK induced lower initial glycaemic responses (P<0.001), whereas AX only reduced the glucose peak value (P<0.001). RK reduced insulin (P<0.001) and GIP responses (P<0.001) compared with the other breads. BG lowered insulin responses more than AX (P<0.001). AX, BG and RK increased satiety feeling (P<0.001) more than WB, but did not differ significantly in terms of subsequent EI (P=0.089). CONCLUSION: BG and RK had beneficial impact on the glucose response, whereas AX had only effect on the postprandial glucose peak. The impact of the AX bread was influenced by higher protein content. Whether the metabolic effects of the breads are still present to mixed meals remains to be tested. [ABSTRACT FROM AUTHOR]

BACKGROUND/OBJECTIVES: Dietary pattern is central in the prevention of hypertension and blood pressure (BP)-related diseases. A diet based on healthy Nordic foods may have a favourable impact on BP. The objective was to clarify whether a Nordic alternative for a healthy food pattern would have beneficial effects on ambulatory BP in subjects with metabolic syndrome (MetS). SUBJECTS/METHODS: In total, 37 subjects were randomized to either a healthy Nordic diet or a control diet. A healthy Nordic diet embraced whole grains, rapeseed oil, berries, fruits, vegetables, fish, nuts and low-fat dairy products of Nordic origin. The mean nutrient intake in the Nordic countries formed the control diet, embracing wheat products, dairy fat-based spread and a lower intake of fruits, vegetables and fish. Diets were isoenergetic. Ambulatory BP was monitored and 24-h urine was collected before and after 12 weeks of intervention. RESULTS: After 12 weeks, ambulatory diastolic BP (-4.4mmHg; P=0.001) and mean arterial pressure (-4.2mm Hg; P=0.006) were lowered by the healthy Nordic diet compared with the control diet, whereas changes in ambulatory systolic BP did not differ significantly between diets (-3.5mmHg; P=0.122). Heart rate tended to be lower in those on the healthy Nordic diet (P=0.057). Urinary sodium and potassium excretions were unaffected by diets and consequently not associated with the healthy Nordic diet-induced lowering of BP. CONCLUSIONS: Consumption of Nordic varieties of health-enhancing foods for 12 weeks decreased diastolic ambulatory BP and mean arterial pressure in subjects with features of MetS during weight-stable condition, suggesting beneficial effects of a healthy Nordic dietary pattern on ambulatory BP. [ABSTRACT FROM AUTHOR]

Background/Objectives:Exacerbated postprandial lipid responses are associated with an increased cardiovascular risk. Dietary proteins influence postprandial lipemia differently, and whey protein has a preferential lipid-lowering effect. We compared the effects of different whey protein fractions on postprandial lipid and hormone responses added to a high-fat meal in type 2 diabetic subjects.Subjects/Methods:A total of 12 type 2 diabetic subjects ingested four isocaloric test meals in randomized order. The test meals contained 100 g of butter and 45 g of carbohydrate in combination with 45 g of whey isolate (iso-meal), whey hydrolysate (hydro-meal), α-lactalbumin enhanced whey (lac-meal) or caseinoglycomacropeptide enhanced whey (CGMP-meal). Plasma concentrations of triglyceride, retinyl palmitate, free fatty acid, insulin, glucose, glucagon, glucagon-like peptide 1 and glucose-dependent insulinotropic peptide were measured before and at regular intervals until 8-h postprandially.Results:We found no statistical significant differences between meals on our primary variable triglyceride. The retinyl palmitate response was higher after the hydro-meal than after the iso- and lac-meal in the chylomicron-rich fraction (P=0.008) while no significant differences were found in the chylomicron-poor fraction. The hydro- and iso-meal produced a higher insulin response compared with the lac- and CGMP-meal (P<0.001). Otherwise no significant differences in the hormone responses were found in the incremental area under the curve over the 480-min period.Conclusions:A supplement of four different whey protein fractions to a fat-rich meal had similar effects on postprandial triglyceride responses in type 2 diabetic subjects. Whey isolate and whey hydrolysate caused a higher insulin response. [ABSTRACT FROM AUTHOR]

Background/Objectives:Postprandial lipaemia is an established risk factor for atherosclerosis. To investigate the acute effect of four milk-derived dietary proteins (alpha-lactalbumin, whey isolate, caseinoglycomacropeptide and whey hydrolysate) on postprandial lipaemia, we have conducted a randomized, acute, single-blinded clinical intervention study with crossover design.Subjects/Methods:A total of 11 obese non-diabetic subjects (age: 44-74, BMI: 30-41.4 kg m-2) were included. On 4 different days the subjects ingested a high-fat meal with the following energy distribution: 66% energy from fat (100 g of butter), 15% of energy from carbohydrate (90 g of white wheat bread) and 19% of energy from protein (45 g of pure protein). Our primary variable was plasma triglyceride measured in the 8-h postprandial period. Secondarily, retinyl palmitate, non-esterified free fatty acids, glucose, insulin, glucagon, GLP-1 and GIP, active and total grehlin and cholecystokinin were measured.Results:We observed no statistically significant (P=0.8) differences between meals on our primary variable that is, triglycerides. Whey hydrolysate was associated with a significantly (P=0.02) smaller postprandial suppression of non-esterified free fatty acids compared with the other dietary proteins.Conclusion:We did not observe significant differences in postprandial lipaemia to the four milk-derived dietary proteins. Whey hydrolysate caused less postprandial suppression of free fatty acids. [ABSTRACT FROM AUTHOR]

Background: Studies on soy supplementation suggest a cardioprotective potential. Objective: To examine the effects on LDL cholesterol and arterial function as a result of dietary enrichment with soy supplementation. Design: A Randomized, double blind, parallel intervention trial. Setting: Department of Endocrinology and Metabolism C, Aarhus University Hospital, and Department of Human Nutrition, The Royal Veterinary and Agricultural University, Denmark. Subjects: In all, 100 hypercholesterolaemic but otherwise healthy subjects were included in the study of which 89 completed it. Interventions: Subjects were randomly assigned to 24 weeks of daily intake of either a soy supplement, Abalon® (30 g soy protein, 9 g cotyledon fibre and 100 mg isoflavones) or placebo (30 g of casein). The soy supplement and placebo were provided in two sachets daily that were stirred in water. Fasting plasma lipids, TNF-α, homocysteine, insulin sensitivity, homeostasis model assessment (HOMA-IR), serum insulin, serum glucose, blood pressure as well as Glucagon-like peptide 1 (GLP-1), glucose-dependent insulinotropic peptide (GIP) and plasma lipids to a fat-rich meal were recorded before and after the intervention. In a sub study in 32 subjects, arterial dilatory capacity, compliance, and distensibility were recorded before and after the intervention. Results: In the main study, no difference in fasting plasma lipid levels or insulin sensitivity was found between soy-based supplement and placebo. A significant postprandial increase in CIP to the meal test was observed in the soy group (P<0.05). In a substudy, no difference between the groups in changes in flow-mediated vasodilatation (P= 0.84) was detected, while the soy supplementation caused a reduction in LDL and total cholesterol. Conclusions: No significant effects on blood lipids were observed in the main study to a soy supplementation in hypercholesterolaemic subjects after 24 weeks. In the substudy, the soy supplementation, however, reduced LDL and total cholesterol but did not influence markers of arterial function. [ABSTRACT FROM AUTHOR]

Aims/hypothesis. The aim of the trial was to compare the efficacy and tolerability of two types of basal-bolus therapy, using either the soluble long-acting basal insulin analogue, insulin detemir, in combination with the rapid-acting analogue, insulin aspart, or NPH insulin in combination with mealtime regular human insulin. Methods. In this 18-week, 1:1 randomised, open-labelled, parallel trial, 595 patients with Type 1 diabetes mellitus received insulin detemir or NPH insulin in the morning and at bedtime in combination with mealtime insulin aspart or regular human insulin respectively. Results. Glycaemic control with insulin detemir/insulin aspart was improved in comparison with NPH insulin/ regular human insulin (HbA1c: 7.88% vs 8.11%; mean difference: -0.22% point [95% CI: -0.34 to -0.10]; p<0.001). Self-measured 8-point plasma glucose profiles differed between the groups (p<0.001), with lower postprandial plasma glucose levels in the insulin detemir/insulin aspart group. Within-person day-to-day variation in plasma glucose was lower with insulin detemir/insulin aspart than with NPH insulin/ regular human insulin (SD: 2.88 vs 3.12 mmol/l; p<0.001). Risk of overall and nocturnal hypoglycaemia (23.00–06.00 hours) was, respectively, 21% (p=0.036) and 55% (p<0.001) lower in the insulin detemir/insulin aspart group than in the NPH insulin/regular human insulin group. Body weight (adjusted for baseline and change in HbA1c) was 1 kg lower with insulin detemir/insulin aspart than with NPH insulin/regular human insulin (p<0.001). Conclusions/interpretation. Basal-bolus therapy using insulin detemir/insulin aspart offers a better balance of control and tolerability than with NPH insulin/regular human insulin. The low variability and more physiological action profiles generated with these insulin analogues resulted in improved glycaemic control with lower risk of hypoglycaemia and no concomitant body weight increase. [ABSTRACT FROM AUTHOR]

Abnormal lipid levels contribute significantly to the risk of coronary heart disease, a major cardiovascular disease and a serious health problem. Various dietary and pharmacologic treatments have been devised to reduce elevated blood cholesterol levels. Soy protein, soluble fiber, and plant sterol/ester-containing margarines are promising new food-component candidates that may help to realize this goal. Of particular interest in this context is the LDL:HDL ratio, a strong predictor of cardiac events. This report is a review of more than 50 recent trials to determine how such dietary components and garlic affect the LDL:HDL ratio and other lipid parameters. Consumption of new soy products containing high, fixed levels of isoflavones, cotyledon soy fiber, and soy phospholipids (Abaco and Abalon) significantly reduced the LDL:HDL ratio by up to 27%. Soluble dietary fibers such as psyllium and beta glucan from oat bran had a variable effect on LDL-cholesterol levels in the studies analyzed. Plant sterol esters, when consumed in margarines, lowered the LDL:HDL ratio by up to 22%. On average, Abacor and Abalon reduced the LDL:HDL ratio by 20%, LDL cholesterol by 15%, total cholesterol by 10%, and triglycerides by 6%, and increased HDL cholesterol by 5%. The new soy-based supplements may therefore play a valuable role in reducing cardiovascular risk. [ABSTRACT FROM AUTHOR]

Evaluates the effect of a diet rich in monounsaturated fatty acids on blood pressure, glycemic control, lipids and insulin sensitivity in women with gestational diabetes mellitus (GDM). Background on GDM; Clinical data of 27 women with GDM; Composition of the diets of the 27 women.

Aims/hypothesis. The amount and quality of fat in the diet could be of importance for development of insulin resistance and related metabolic disorders. Our aim was to determine whether a change in dietary fat quality alone could alter insulin action in humans. Methods. The KANWU study included 162 healthy subjects chosen at random to receive a controlled, isoenergetic diet for 3 months containing either a high proportion of saturated (SAFA diet) or monounsaturated (MUFA diet) fatty acids. Within each group there was a second assignment at random to supplements with fish oil (3.6 g n-3 fatty acids/d) or placebo. Results. Insulin sensitivity was significantly impaired on the saturated fatty acid diet (-10 %, p = 0.03) but did not change on the monounsaturated fatty acid diet ( + 2 %, NS) (p = 0.05 for difference between diets). Insulin secretion was not affected. The addition of n-3 fatty acids influenced neither insulin sensitivity nor insulin secretion. The favourable effects of substituting a monounsaturated fatty acid diet for a saturated fatty acid diet on insulin sensitivity were only seen at a total fat intake below median (37E %). Here, insulin sensitivity was 12.5 % lower and 8.8 % higher on the saturated fatty acid diet and monounsaturated fatty acid diet respectively (p = 0.03). Low density lipoprotein cholesterol (LDL) increased on the saturated fatty acid diet ( + 4.1 %, p < 0.01) but decreased on the monounsaturated fatty acid diet (MUFA) (–5.2, p < 0.001), whereas lipoprotein (a) [Lp(a)] increased on a monounsaturated fatty acid diet by 12 % (p < 0.001). Conclusions/interpretation. A change of the proportions of dietary fatty acids, decreasing saturated fatty acid and increasing monounsaturated fatty acid, improves insulin sensitivity but has no effect on insulin secretion. A beneficial impact of the fat quality on insulin sensitivity is not seen in individuals with a high fat intake ( > 37E %). [Diabetologia (2001) 44: 312–319] [ABSTRACT FROM AUTHOR]

Objective: Recent studies have demonstrated beneficial metabolic effects of dietary monounsaturated fatty acids (MUFA) in Type-2 diabetes mellitus (Type-2 DM). The question arises if dietary MUFA also has desirable effects on risk markers in subjects with high risk of developing Type-2 DM.Setting: University department of endocrinology.Subjects: Sixteen healthy, first-degree relatives (six men, 10 women, age (mean+/-s.d.): 35+/-2 years) with normal oral glucose tolerance tests.Interventions: Randomised study with two 4-week treatment periods with either a carbohydrate-rich (CHO) diet (55 E% carbohydrate, 30 E% fat, 15 E% protein) or a diet rich in olive oil [MUFA 40 E% fat (25 E% as MUFA), 45 E% carbohydrate, 15 E% protein]. The periods were divided by a 4-week wash-out period.Results: Similar lowering effects on total cholesterol, low density lipoprotein (LDL)-cholesterol, triglyceride and apoB levels were seen after the two diets. Slightly higher levels of high-density lipoprotein (HDL)-cholesterol (1.4+/-0.4 vs 1.3+/-0.4 mmol/l, P<0. 0001) and apoA-1 (1.2+/-0.3 vs 1.1+/-0.3 mmol/l, P<0.05) were found in the MUFA-diet. Furthermore, the insulin sensitivity, as assessed by Bergman's minimal model, and the first response insulin areas were similar, as were the 24-h blood pressures and the von Willebrand Factor (vWF) levels.Conclusions: Isocaloric diets rich in MUFA or rich in carbohydrate, respectively, seem to have similar effects on cardiovascular risk factors in persons at high risk of developing Type-2 DM. A potential risk, however, on body weight of high-fat diets should be kept in mind.Sponsorship: This study was supported by grants from the Danish Diabetes Association, Institute of Clinical Experimental Research, Aarhus University, The Danish Heart Foundation, The Danish Medical Research Council, Velux Foundation, Poul and Erna Sehested Hansens Foundation, Mogens Svarre Mogensens Foundation. [ABSTRACT FROM AUTHOR]

Aims/hypothesis. The circulating concentrations of endothelin-1 (ET-1), a peptide derived from endothelium, are increased in hypertension and diabetes. Endothelin-1 has recently been shown to be an insulinotropic agent. The mechanism of action of endothelin-1 on the endocrine pancreas has not yet been clarified. Methods. We investigated the action of endothelin-1 on the insulin secretion, the binding of 125I-ET-1 to beta cells as well as its effects on purified beta and non-beta cells from normal rats. The expression of endothelin receptors in alpha- and beta-cell lines and in normal rat islets was also studied. Results. First, we studied the effects of endothelin-1 on insulin secretion from beta-cell lines (INS-1, βTC3 and MIN6). At all endothelin-1 concentrations applied (1 pmol/l to 1 μmol/l) no change in insulin secretion was found. Ligand-binding experiments on βTC3 cells showed no specific binding of 125I-ET-1. A prominent expression of ETA-receptor mRNA in an alpha-cell line (αTC1.9) and in normal rat islets was found whereas no expression was found in INS-1 cells. No influence of endothelin-1(1 μmol/l) on insulin secretion stimulated by glucose was detected from purified beta cells. Endothelin-1-(100 nmol/l) increased, however, both insulin and glucagon secretion from a mixture of purified beta and non-beta cells indicating that alpha cells seem to have a key role for the action of ET-1 on insulin secretion. Conclusion/interpretation. The insulinotropic impact of endothelin-1 is not caused by a direct action on the beta cells but seems to be mediated by a paracrine action, probably secondary to enhanced release of glucagon from the endothelin receptor positive alpha cells. [Diabetologia (1999) 42: 1302–1307] [ABSTRACT FROM AUTHOR]

The current view of dietary carbohydrates as simply providing us with energy is outdated. Because of their varied chemistry and physical form the rate and extent to which the different types are digested in and absorbed from the small intestine varies. This in turn leads to affects on satiety, blood glucose and insulin, protein glycosylation, lipids and bile acids. Some carbohydrates reach the colon where they are fermented and affect many aspects of large bowel function, colonocyte and hepatic metabolism. A new framework for classifying and measuring food carbohydrates is needed to allow a greater understanding of the role of individual species in health and to inform the public of their importance. A classification based primarily on molecular size (degree of polymerisation) into sugars, oligosaccharides and polysaccharides, is suggested, with sub-groups identified by the nature of the monosaccharides. Greater knowledge of the chemical and physical properties of carbohydrates allow a more precise relation with physiology and health to be drawn. The Carbohydrate Group met in Paris in December 1995 at the invitation of Gerard Pascal, Director of CNERNA. Financial support for the meeting was provided by CNERNA. [ABSTRACT FROM AUTHOR]

Endothelin-1 (ET-1), a potent endothelium-derived vasoconstrictor peptide, is secreted in response to insulin. Elevated circulating ET-1 levels have been found in patients with diabetes mellitus and vascular dysfunction. The question arises whether ET-1 acts as a direct modulator of insulin secretion. To test this, we studied the effects of ET-1 on isolated mouse islets of Langerhans. ET-1 (1 nmol/l-1 Μmol/l) dose-dependently stimulated insulin secretion from islets incubated in the presence of 16.7 mmol/l glucose ( p<0.05). The effect of ET-1 is glucose-dependent since no potentiation was found at 3.3 mmol/l glucose. Furthermore, ET-1 induced a large, transient increase in glucose-stimulated insulin secretion during islet perifusion in the presence ( p<0.001), but not in the absence, of extracellular Ca. The rate of Ca-efflux from Ca-prelabelled islets was transiently stimulated by ET-1 during perifusion at 16.7 mmol/l glucose in the presence of extracellular Ca ( p<0.001). A short-lived increase in Ca-efflux was also observed in the absence of extracellular Ca ( p<0.05). It is suggested that the effects of ET-1 on insulin secretion are critically dependent on influx via Ca-channels. In addition, ET-1 transiently enhanced Rb-efflux from Rb-prelabelled islets both in the presence ( p<0.001) and in the absence ( p<0.001) of extracellular Ca suggesting that ET-1 does not elicit insulin secretion by inhibition of the potassium permeability. Our study provides evidence that ET-1 stimulates insulin secretion via a direct effect on the islets of Langerhans. [ABSTRACT FROM AUTHOR]

Previous studies have shown that unsaturated fat-enriched diets may have a beneficial effect on blood pressure in non-insulin-dependent diabetic (NIDDM) patients, whereas little is known about the effects on albuminuria. In a 3-week cross-over design we compared the effects of a currently recommended high-carbohydrate diet (50% carbohydrate, 30% fat [10% monounsaturated fat]) vs a diet rich in monounsaturated fat (30% carbohydrate, 50% fat [30% monounsaturated fat]) on urinary albumin excretion rate, 24-h ambulatory blood pressure and metabolic control in ten NIDDM patients with persistent microalbuminuria. The 24-h ambulatory blood pressure was similar before and after both the high-carbohydrate diet (mean±SD: 145/78±25/10 vs 143/79±19/10 mmHg (NS) and the monounsaturated fat diet: 140/78±16/8 vs 143/79±15/8 mmHg (NS). No changes were observed in day or night-time blood pressures. Urinary albumin excretion rate was unaffected after 3 weeks' treatment by the diets: from (geometric mean ×/÷ tolerance factor) 32.4×/÷2.1 to 36.0×/÷1.9 Μg/min (NS) vs from 34.2×/÷1.9 to 32.1×/÷2.1 Μg/min (NS). Fasting plasma glucose, serum fructosamine and HbA as well as lipid and lipoprotein concentrations were stable during both diets. Compared to the high-carbohydrate diet a reduction in the LDL/HDL cholesterol ratio was observed during the monounsaturated fat diet (p<0.03). In conclusion, compared to a high-carbohydrate diet, 3 weeks' treatment with a monounsaturated fat diet did not affect the levels of 24-h ambulatory blood pressure or albuminuria in microalbuminuric NIDDM patients. Moreover, glycaemic control and lipoprotein levels were unchanged, although a potential beneficial effect on the LDL/HDL-cholesterol ratio was noted. Monounsaturated fat represents an alternative in the diets of NIDDM patients especially when caloric intake is not a concern. [ABSTRACT FROM AUTHOR]

The appearance of microalbuminuria in diabetic patients predicts development of macroalbuminuria and coronary heart disease. Autonomic dysfunction in ischaemic heart disease is related to an increased incidence of arrhythmic deaths. To assess sympathovagal balance in relation to microalbuminuria we performed 24-h spectral analysis of RR interval oscillations in 37 insulin-dependent diabetic patients. Patients were divided according to urinary albumin excretion as normo-(<20 Μg/min) ( n=12), micro-(>20 and <200 Μg/min) ( n=14) and macro-albuminuria (>200 Μg/min) ( n=11). None had symptoms or signs of ischaemic heart disease at clinical examination or during stress testing. Fourteen matched healthy subjects served as controls. Overall RR interval variability was calculated as the 24-h standard deviation. The square root of power of the low-frequency (0.04-0.15 Hz) and high-frequency (0.15-0.40 Hz) component were considered indices of the sympathovagal interaction and vagal function, respectively. Patients with micro and macroalbuminuria had, compared to control subjects, significantly reduced 24-h standard deviation, a much smaller day/night difference in mean RR level and a significantly reduced amplitude of the low frequency and high frequency oscillations, which were even more reduced in macroalbuminuria. The differences in vagal function were also present after correction for mean RR level, and differences in physical training level and smoking. Insulin-dependent diabetic patients who develop microalbuminuria have significantly impaired vagal function and abnormal sympathovagal interaction, which is further deranged in macroalbuminuria. This early autonomic dysfunction may later contribute to a increased risk for sudden cardiac death. [ABSTRACT FROM AUTHOR]

The blood glucose responses to cooked potato, rice and spaghetti were studied in six Type 1 (insulin-dependent) diabetic patients who had attained euglycaemia by the artificial pancreas prior to the meal intake. The amount of potato (raw weight 200 g), parboiled rice (raw weight 50 g), and spaghetti (raw weight 50 g) had approximately identical caloric content (range 203-225 kcal) and amount of available carbohydrate (range 39.4-43.4g). The postprandial blood glucose response areas after cooked potato and cooked parboiled rice were similar (180 min values: cooked potato: 1190 ±110 mmol/l x min, cooked rice: 1160 ± 140 mmol/l x min and 240min values: cooked potato: 1690 ± 140 mmol/l x min, cooked rice: 1740 ± 210 mmol/l x min). In contrast, the response after cooked spaghetti was slower and less pronounced (180 min value: 830 ± 80 mmol/1 x min and 240 min value: 1320 ± 120 mmol/1 x min), and was significantly smaller than those of cooked potato (180 min: 2 p < 0.01 and 240 min: 2 p < 0.01) as well as cooked rice (180 min: 2 p < 0.01 and 240 min: 2 p < 0.02). Our study emphasizes the importance of determining the glycaemic response of foodstuffs under conditions of isoinsulinaemia. [ABSTRACT FROM AUTHOR]

Cardiac function was investigated by echocardiography in 24 short-term Type 1 diabetic patients with a mean diabetes duration of 7 years (range 4-14 years) during conditions of ordinary metabolic control. Compared to 24 age and sex matched normal control subjects, measurements of myocardial contractility as left ventricular fractional shortening and mean circumferential shortening velocity were increased by 12% and 20% respectively. Another 8 Type 1 diabetic patients were examined during conditions of poor (hyperglycaemia and ketosis) and good metabolic control. Following improved glycaemic control, left ventricular fractional shortening and mean circumferential shortening velocity decreased by 16% and 24% respectively. Our findings show that short-term Type 1 diabetes is associated with increased myocardial contractility. Furthermore, this condition is related to the state of metabolic control. [ABSTRACT FROM AUTHOR]

Pancreatic D and A cell function is deranged in streptozotocin diabetes. To investigate this, the effect of D-glyceraldehyde, dihydroxyacetone, D-mannoheptulose and glucose variations during arginine stimulation on the release of somatostatin and glucagon from the isolated pancreas of normal and streptozotocin diabetic dogs was studied. Concentrations of the trioses, D-glyceraldehyde (1.25 and 2.5 mmol/l) and dihydroxyacetone (11 mmol/l), which normally stimulate D cells, did not influence the release of somatostatin in the diabetic dog. However, the higher concentration of D-glyceraldehyde (5 mmol/l) suppressed D cell secretion in the diabetic animals at 0 and 8.3 mmol/l glucose. A cell secretion was significantly suppressed at the higher glucose level in response to both 2.5 and 5 mmol/l of the triose. This inhibition may be explained by a non-specific effect induced by the high dose of this triose. The addition of 5 mmol/l mannoheptulose, which normally reduces glucose-induced somatostatin secretion and stimulates glucagon release, did not affect hormone secretion. In both the diabetic and the normal animals, arginine (5 mmol/l) stimulated somatostatin and glucagon secretion. Although arginine was able to stimulate D and A cell secretion in the diabetic dogs, it was however unable to restore the response to changes in glucose concentration between 1.4 and 8.3 mmol/l to normal. These results demonstrate that the abnormal pancreatic D and A cell function in streptozotocin diabetes is characterised by an impaired response to glucose and certain glucose metabolites and probably results from a specific defect in glucose recognition. [ABSTRACT FROM AUTHOR]

The role of cyclic AMP in the control of somatostatin release may be primarily that of a modulator without being an essential factor for initiation of somatostatin release. Much work is, however, still required to elucidate the exact nature of the role of cyclic AMP in the secretory mechanism of the D cell. All of the present evidence, however, points to a key regulatory role for calcium in the cascade of events that proceeds to the somatostatin secretion [24, 26, 30-33]. The data indicate that the changes in somatostatin secretion provoked by alterations in the extra-and intracellular levels of Na and K are secondary to changes in the intracellular level of calcium in the D cell. Caution should, however, be exercised in deducing from the results from cation fluxes in whole islets because of the mixed cell population studied. They cannot be assumed to represent the responses of the D cell alone because these cells make up only 5-15% of the total cell mass in the islet. [ABSTRACT FROM AUTHOR]

Somatostatin release from the isolated pancreas of 3 normal and 6 streptozotocin diabetic dogs has been measured in response to various stimuli to determine whether abnormalities in somatostatin release are present in the diabetic pancreas. Simultaneous measurement of glucagon secretion was also made. In the pancreas from normal dogs increases in perfusate glucose from 25 to 200 mg/100 ml induced a 2-3 fold increase in somatostatin release and a two thirds decrease in glucagon secretion. In contrast, in the diabetic pancreas glucose caused no change in the secretion of the two hormones. In the diabetic pancreas addition of insulin to the perfusate (25,000 μU/ml) for periods from 10 to 75 minutes aimed at restoring normal extracellular insulin levels in the islets failed to restore either somatostatin or glucagon secretion to normal. In contradistinction to the lack of effect of glucose, the somatostatin and glucagon responses to arginine (5 mmol/l), isoproterenol (2 ng/ml) and calcium (5 mmol/l) were normal in the diabetic pancreas. The data suggests the presence of a selective glucoreceptor abnormality of the D as well as of B and A cells in the streptozotocin diabetic dog. [ABSTRACT FROM AUTHOR]

The effect of calcium on somatostatin secretion was investigated in the isolated, perfused canine pancreas preparation and compared with those of acetylcholine, glucose, isoproterenol and arginine. Calcium (5 mmol/l) stimulated somatostatin release in a typical biphasic response pattern being about 5 times as potent as acetylcholine (1 μmol/l), arginine (5 mmol/l), and isoproterenol (2 ng/ml) while the release of insulin and glucagon in response to calcium and the other secretagogues were of the same magnitude. Somatostatin release increased progressively when perfusate calcium was increased step-wise from 0 through 1.25 and 2.5 to 5.0 mmol/l. Calcium stimulated the secretion of somatostatin in the absence of glucose. The stimulatory effect of calcium was, however, modulated by the glucose concentration being about twice as large at 200 mg/100 ml as at 25 mg/100 ml glucose in the perfusion medium. [ABSTRACT FROM AUTHOR]

Since Mn apparently interferes with excitation-contraction coupling by both reducing inward movement of Ca across the cell membrane and by displacing Ca from an intracellular store, studies were performed in the isolated, perfused canine pancreas to elucidate the existence of a similar effect in stimulus-secretion coupling and to draw comparisons with the effect of Mg, which antagonizes Ca at the cell membrane. The results show: 1. that Mn (0.05, 0.125, and 0.25 mmol/l) inhibits the release of insulin and glucagon in a dose-dependent fashion during the first 3-4 min of infusion followed by a dose-dependent increase in hormone release, the 'escape phase'. 2. The inhibitory action of Mn (0.25 mmol/l) upon release of both hormones is progressively counteracted when perfusate calcium is increased from 0.7 to 1.3 to 5.0 mmol/l. 3. Mg (5 mmol/l) inhibits the release of both hormones with no sign of an 'escape phase'. 4. Mn (0.5 mmol/l) during calcium depletion causes a gradual stimulation of the release of both hormones. The dual action of Mn upon hormone release from the endocrine pancreas suggests that Mn can cross the cell membrane and can interfere with stimulus-secretion coupling both at the membrane level, by competitively inhibiting the Ca influx, and at some intracellular level by releasing calcium from an intracellular store. [ABSTRACT FROM AUTHOR]

The effect of haloperidol, a dopaminergic antagonist, on insulin and glucagon secretion was investigated using the isolated, perfused canine pancreas. Haloperidol at 4 × 10 to 10 mol/l caused a dose-dependent inhibition of glucagon release both at low (25 mg/100 ml) and high glucose concentrations (150 mg/100 ml). At the low glucose concentration insulin release was already maximally suppressed. At the high glucose concentration haloperidol (4 × 10 to 10 mol/l) also caused a dose-dependent inhibition of insulin release. Haloperidol (10 mol/l) inhibited dramatically pancreatic A and B cell responses to isoproterenol (2 ng/ml), acetylcholine (1 μmol/l) and arginine (5mmol/l). The inhibitory effect of haloperidol on both glucagon and insulin release could be eliminated by increasing perfusate calcium concentration from 1.3 to 8.8 mmol/l. These findings suggested that haloperidol blocks glucagon and insulin release in a somatostatin-like manner by affecting a fundamental step of the stimulus-secretion coupling, probably by interfering with calcium handling of the pancreatic A and B cells. [ABSTRACT FROM AUTHOR]

The release of pancreatic polypeptide (PP) by gut hormones, acetyl choline and adrenaline was investigated in an isolated perfused pancreas preparation. PP was potently released by 1 nmol/l caerulein (186±12%, p<0.001) and gastric inhibitory peptide (GIP) (211±31%, p<0.005) as well as by 1 [νmol/l acetyl choline (1097±59%, p<0.001). A significant two-fold release of PP was also evoked by 1 nmol/l vasoactive intestinal peptide (VIP) (129±38%, p<0.02 and gastrin (108±25% p<0.01). Insulin release, induced by high glucose concentration was enhanced by both GIP (210 ±38%, p<(0.01) and VIP (48±5%, p<0.001). In addition GIP enhanced the release of glucagon by 179±18% (p<0.001) at 1.4 mmol/l glucose and by 127±24% (p<0.005) at 8.3 mmol/l glucose. Thus no simple inter-relationship appears to exist between the control of the three circulating islet hormones. [ABSTRACT FROM AUTHOR]

Using the isolated, perfused canine pancreas the importance of calcium for the normal secretory function of the pancreatic alpha cell was investigated. It was found that 1. increases in perfusate Ca from 1.3 to 4.8 mM and from 1.3 to 8.2 mM during perfusion with glucose concentrations of 25 and 150 mg/100 ml stimulate the release of both glucagon and insulin in a dose-related and a glucose-dependent fashion. The hormone responses to increases in calcium were, with few exceptions, biphasic 2. a 'Ca free' medium inhibited release of both hormones, and increases in perfusate glucose from 25 to 150 mg/100 ml were unable to suppress glucagon or to stimulate insulin. Addition of calcium (8.2 mM) resulted in re-establishment of the normal regulatory role of glucose upon release of both hormones, now being in a hyperactivated state by the high Ca concentration; 3. sudden Ca depletion of the perfusate from 2 mM at a glucose concentration of 200 mg/100 ml inhibited immediately the release of both hormones to very low levels, which remained low until the addition of Ca (2 mM). Ca is therefore an essential requirement for the normal secretory process of pancreatic glucagon, possibly involving uptake and accumulation within the A cell, as established for the B cell. It is suggested that Ca exerts its effect on the microtubular microfilamentous system. [ABSTRACT FROM AUTHOR]

A correction to the article "A New Look at Dietary Carbohydrate: Chemistry, Physiology and Health," by J.H. Cummings and colleagues that was published in a previous issue is presented.