Microdosing of a Carbon-14 Labeled Protein in Healthy Volunteers Accurately Predicts Its Pharmacokinetics at Therapeutic Dosages.

Preclinical development of new biological entities (NBEs), such as human protein therapeutics, requires considerable expenditure of time and costs. Poor prediction of pharmacokinetics in humans further reduces net efficiency. In this study, we show for the first time that pharmacokinetic data of NBEs in humans can be successfully obtained early in the drug development process by the use of microdosing in a small group of healthy subjects combined with ultrasensitive accelerator mass spectrometry (AMS). After only minimal preclinical testing, we performed a first-in-human phase 0/phase 1 trial with a human recombinant therapeutic protein (RESCuing Alkaline Phosphatase, human recombinant placental alkaline phosphatase [hRESCAP]) to assess its safety and kinetics. Pharmacokinetic analysis showed dose linearity from microdose (53 µg) [(14) C]-hRESCAP to therapeutic doses (up to 5.3 mg) of the protein in healthy volunteers. This study demonstrates the value of a microdosing approach in a very small cohort for accelerating the clinical development of NBEs.

Nutrigenomics approach elucidates health-promoting effects of high vegetable intake in lean and obese men.

We aimed to explore whether vegetable consumption according to guidelines has beneficial health effects determined with classical biomarkers and nutrigenomics technologies. Fifteen lean (age 36 ± 7 years; BMI 23.4 ± 1.7 kg m(-2)) and 17 obese (age 40 ± 6 years; BMI 30.3 ± 2.4 kg m(-2)) men consumed 50- or 200-g vegetables for 4 weeks in a randomized, crossover trial. Afterward, all subjects underwent 4 weeks of energy restriction (60 % of normal energy intake). Despite the limited weight loss of 1.7 ± 2.4 kg for the lean and 2.1 ± 1.9 kg for the obese due to energy restriction, beneficial health effects were found, including lower total cholesterol, LDL cholesterol and HbA1c concentrations. The high vegetable intake resulted in increased levels of plasma amino acid metabolites, decreased levels of 9-HODE and prostaglandin D3 and decreased levels of ASAT and ALP compared to low vegetable intake. Adipose tissue gene expression changes in response to vegetable intake were identified, and sets of selected genes were submitted to network analysis. The network of inflammation genes illustrated a central role for NFkB in (adipose tissue) modulation of inflammation by increased vegetable intake, in lean as well as obese subjects. In obese subjects, high vegetable intake also resulted in changes related to energy metabolism, adhesion and inflammation. By inclusion of sensitive omics technologies and comparing the changes induced by high vegetable intake with changes induced by energy restriction, it has been shown that part of vegetables' health benefits are mediated by changes in energy metabolism, inflammatory processes and oxidative stress.

Short-term digestive tolerance of different doses of NUTRIOSE FB, a food dextrin, in adult men.

OBJECTIVE: To determine the tolerance of increasing dosages of an incompletely hydrolysed and/or incompletely absorbed food dextrin coming from wheat starch, NUTRIOSE FB, at daily levels of 10 and 15 g up to 60 and 80 g, respectively. DESIGN: A randomized, double-blind, multiple dose, placebo-controlled, combined crossover and parallel trial. SETTING: The metabolic ward of TNO Nutrition and Food Research. SUBJECTS: A total of 20 healthy men (age 31.7 +/- 9.1 y; BMI 24.5 +/- 2.9 kg/m2). INTERVENTION: One group of 10 subjects consumed on top of their diet 10, 30 and 60 g of NUTRIOSE FB or maltodextrin (placebo) daily. The other group of 10 subjects consumed 15, 45 and 80 g daily. Each dose was consumed for 7 days. RESULTS: Compared with placebo, flatulence occurred more frequently over the last 6 days on 30, 60 or 80 g/day of NUTRIOSE FB (P < 0.05). During the last 24 h, that is, days 6-7, of 60 and 80 g/day of NUTRIOSE FB, the frequency of flatulence was even higher (P < 0.05). During the last 24 h on a daily dose of 60 g NUTRIOSE FB, the frequency of defecation decreased (P < 0.05). Bloating occurred more often during the last 24 h on 80 g/day of NUTRIOSE FB (P < 0.05). None of the doses of NUTRIOSE FB resulted in diarrhoea. Compared to baseline levels, breath H2 excretion, which was only measured after a week with 10 and 15 g of NUTRIOSE FB daily, increased (P < 0.05). However, no difference in area under the curve was found. CONCLUSIONS: NUTRIOSE FB is a fermentable carbohydrate and is well tolerated up to a dose of 45 g daily. Higher daily dosages (60 and 80 g) may result in flatulence, but does not result in diarrhoea. SPONSORSHIP: TNO Nutrition and Food Research was assigned by Roquette Frères to perform the study.

Effect of two breakfasts, different in carbohydrate composition, on hunger and satiety and mood in healthy men.

OBJECTIVE: To study the effect of simple vs complex carbohydrates (SCHO and CCHO respectively) containing breakfasts on blood parameters, hunger and satiety and mood. DESIGN: A 2-day, open, randomised, cross-over trial. SUBJECTS: A total of 26 male subjects (34+/-6 y; BMI 23.4+/-2.2 kg m(-2)). MEASUREMENTS: Blood glucose, insulin, triacylglycerols (TG), free fatty acids (FFA) and cholecystokinin (CCK) were determined repeatedly for 4 h on both test days after a breakfast containing SCHO or CCHO. Feelings of hunger and satiety were determined at similar time points as well. Mood state was examined 3 h after breakfast consumption. RESULTS: Consumption of a SCHO breakfast resulted in higher glucose and insulin levels at 30 min after breakfast consumption. TG at 180 min, and FFA at 180 and 240 min were higher after SCHO breakfast than after CCHO breakfast. Satiety scores were higher after CCHO breakfast consumption for the first 90 min after intake. Furthermore, the item 'fatigue' was scored higher after SCHO breakfast than after CCHO breakfast intake. CONCLUSION: Consumption of a CCHO breakfast is favourable in comparison to a SCHO breakfast, because of the lower perception of 'fatigue' and the higher degree of satiety after consumption.

Effects of sugar intake on body weight: a review.

Weight reduction programmes are mainly focused on reducing intake of fat and sugar. In this review we have evaluated whether the replacement of dietary (added) sugar by low-energy sweeteners or complex carbohydrates contributes to weight reduction. In two experimental studies, no short-term differences in weight loss were observed after use of aspartame as compared to sugar in obese subjects following a controlled energy-restricted diet. However, consumption of aspartame was associated with improved weight maintenance after a year. In two short-term studies in which energy intake was not restricted, substitution of sucrose by artificial sweeteners, investigated mostly in beverages, resulted in lower energy intake and lower body weight. Similarly, two short-term studies, comparing the effect of sucrose and starch on weight loss in obese subjects did not find differences when the total energy intake was equal and reduced. An ad libitum diet with complex carbohydrates resulted in lower energy intake compared to high-sugar diets. In two out of three studies, this was reflected in lower body weight in subjects consuming the complex carbohydrate diet. In conclusion, a limited number of relatively short-term studies suggest that replacing (added) sugar by low-energy sweeteners or by complex carbohydrates in an ad libitum diet might result in lower energy intake and reduced body weight. In the long term, this might be beneficial for weight maintenance. However, the number of studies is small and overall conclusions, in particular for the long term, cannot be drawn.

A model for regulation of the Mg(2+)-stimulated acto-myosin-ATPase activity: inhibition of the formation of actin-myosin complex and the Mg( 2+)-stimulated acto-myosin-ATPase activity by IMP and AMP.

Previously, we showed that the decrease in force output during continuous isometric contractions in rat skeletal muscle was related to an increase in the concentration of IMP. In this paper we report on additional experiments in which the effect of IMP on the Mg(2+)-stimulated acto-myosin-ATPase activity of isolated actin and myosin is measured at 35 degrees C. The results show that 1) the binding of actin to myosin is co-operative (Hill coefficient = 3.82); 2) in the presence of IMP or AMP the Mg(2+)-stimulated acto-myosin-ATPase activity is inhibited up to 60% at 10 mM; 3) in the presence of IMP or AMP not only the Mg(2+)-stimulated acto-myosin-ATPase activity decreases, but also K(50). From these results we conclude that IMP and AMP may be considered as uncompetitive inhibitors. Our results suggest that IMP and AMP can prevent an 'energy crisis' during exhaustive exercise of short duration by down-regulating the contractile machinery.

Predictors of weight maintenance.

OBJECTIVE: To obtain predictors of weight maintenance after a weight-loss intervention. RESEARCH METHODS AND PROCEDURES: An overall analysis of data from two-long intervention studies [n=67 women; age: 37.9+/-1.0 years; body weight (BW): 87.0+/-1.2 kg; body mass index: 32.1+/-0.5 kg.m(-2); % body fat: 42.4+/-0.5%]. Subjects were measured before a very low energy diet (month 0), after the very low energy diet of 2 months (month 2) and after a 14-month follow-up phase (at 16 months), in which fiber or a carbohydrate-containing food supplement was supplied. The baseline measurements and the changes in parameters induced by the diet intervention were used to predict the changes in BW in the follow-up phase [deltaBW(2-16)]. RESULTS: Multiple regression analysis revealed that 50% (p<0.001) of the variability in weight regain could be explained by physiological and behavioral factors. These were: frequency of previous dieting (r2=0.27, p<0.05), hunger score (measured with the three-factor eating behavior questionnaire), and change in 24-hour resting metabolic rate (RMR). Frequent dieters showed significantly more weight regain than less frequent dieters (8.8+/-1.0 kg vs. 5.1+/-0.8 kg, p<0.01). Subjects having parents with obesity regained almost significantly more weight than subjects with lean parents (8.5+/-0.2 kg vs. 5.1+/-1.5 kg, respectively; p = 0.06). DISCUSSION: Physiological (deltaRMR-24 hours) and behavioral factors (previous frequency of dieting and hunger score) predicted failure of weight maintenance and, as such, can be used to identify women who are at risk for weight regain.

Effect of exercise training on long-term weight maintenance in weight-reduced men.

This study investigated whether endurance training is effective for successful long-term weight maintenance after weight reduction. Fifteen male obese subjects (age, 37.3+/-5.2 years; body weight [BW], 96.2+/-13.6 kg; body mass index [BMI], 30.9+/-2.8 kg x m(-2)) participated in a 16-month exercise-intervention study. During the first 4 months, all subjects trained three to four times weekly, consuming a very-low-energy diet (VLED) during the first 2 months. After the 4-month treatment period, seven subjects continued training for 12 months (3 to 4 times per week). The other eight subjects served as a control group not involved in a training program. The regain (increase during the intervention period as a percentage of the 4-month treatment) of BW at 16 months was 64% (+/-26%) for the whole group (trained v. control, 52%+/-28% v. 74%+/-20%, P = .09). The increase in absolute fat mass (FM) was significantly lower at 16 months for the trained group (trained v. control, 4.8+/-1.9 v. 9.0+/-3.3 kg), as was the regain of FM at 16 months (trained v. control, 61%+/-24% v. 92%+/-32%, P = .05). The amount of regain of the waist circumference, waist to hip ratio (WHR), and sagittal diameter were correlated with the amount of training (hours) performed weekly (deltawaist, r = -.55, P<.05; deltaWHR, r = -.50, P = .06; deltasagittal diameter, r = -.53, P<.05). Physical fitness parameters (maximal power output [Wmax] and oxygen uptake [Vo2 max]) were significantly increased in both groups at 4 months. Trained subjects maintained high levels of physical fitness at 16 months, in contrast to the control group. In conclusion, although BW regain was not significantly different between the groups, trained subjects showed less regain of FM and higher levels of physical fitness, factors related to a lower risk for cardiovascular disease (CVD), compared with the control group. Furthermore, the regain of FM, which occurred even in the exercising group with a relatively intensive training program, suggests that maintenance of fat loss is extremely difficult.

The effect of body weight changes and endurance training on 24h substrate oxidation.

OBJECTIVE: To investigate the effect of exercise training and dietary macronutrient composition on 24 h substrate oxidation in male, obese subjects. DESIGN: A 16 month exercise intervention study was executed, including a weight loss period with a very low energy diet (VLED) for 2 months at the start of the study. SUBJECTS: Twelve male, obese subjects (age 36.3+/-5.1 y; body weight 94.6+/-13.9 kg; body mass index, BMI 30.8+/-3.0 kg/m2) and in an additional study 15 lean, well-trained subjects (age 36.2+/-7.2 y; body weight 72.2+/-5.9 kg; BMI 22.3+/-1.7 kg/m2) participated. MEASUREMENTS: Substrate oxidation was measured during a standardized 36 h stay in the respiration chamber at the start of the study (0 months), and at 4, 10 and 16 months. In the respiration chamber subjects were randomly assigned to a high-fat (Hi.F) diet (60% of energy (En%) fat) or a reduced-fat (Red.F) diet (30 En% fat). The well-trained group was measured once in the respiration chamber for 36 h according to the same protocol. RESULTS: At any time point, independent of the diet consumed, the 24 h carbohydrate (CHO) balances in the chamber were mostly negative (means ranging from +31 to -98 g/d) and the fat balances mostly positive (means ranging from -26 to +38 g/d) for the obese a well as for the lean, well-trained group. For both diets an increased shortage of 70 g of CHO was found at 16 months compared with 4 months, and an increase in fat balance of 33 g during the same time period in the obese subjects, indicating that CHO oxidation had increased with 12 months endurance training. In the well-trained group the 24h CHO balance was even more negative for both types of diet (-103 to -185 g/d for the Red.F and Hi.F diet, respectively) under similar conditions compared with the trained obese group. CONCLUSION: The changes in 24 h substrate utilization in the obese, as well as in the well-trained group, suggest that endurance training increased the reliance on carbohydrate oxidation and therefore did not increase 24 fat oxidation.

The effect of exercise training on leptin levels in obese males.

The effect of endurance training on plasma leptin levels was investigated in 15 obese male subjects (age 37.3 +/- 5.2 yr, body weight 96.5 +/- 13.6 kg, and body mass index 29.8 +/- 3.0 kg/m2) in a weight loss and exercise program. After 4 mo of treatment consisting of a very low energy diet (VLED) and endurance exercise training (3-4 times weekly, 1 h sessions, moderate intensity), two groups were formed. One group continued the exercise sessions (trained subjects, n = 7) and the other group stopped with the exercise program (control, n = 8). Measurements of anthropometry, aerobic power, and fasted blood samples were executed at fixed time points (0, 2, 4, 10, and 16 mo). With partial regression analysis, keeping the changes in insulin and body fat percentage constant, it was shown that the number of hours of exercise training was significantly correlated with changes in leptin levels, during the 16-mo period (r = 0.56, P < 0.05). Changes in insulin levels were significantly related to the changes in leptin levels (r = 0.47, P < 0.05), which were less for changes in body fat percentage (r = 0.42, P = 0.07). During the VLED, the change in insulin concentration affected leptin levels significantly (r = 0.79) but changes in body fat percentage were not noted. It is concluded that endurance exercise training decreased plasma leptin levels independently of changes in plasma insulin levels and body fat percentage.

Effect of one week of fibre supplementation on hunger and satiety ratings and energy intake.

The effect of one week of supplementation with a water-soluble fibre (guar gum) was studied in obese women who had lost weight. In study 1 (N=17; mean+/-SEM: age 38.5+/-2.3 yrs; weight 86.8+/-2.3 kg; BMI 32.2+/-0.9 kg.m-2) energy intake and hunger and satiety scores were assessed under free-living conditions. In study 2 (N=14; age 44. 5+/-1.8 yrs; weight 78.8+/-3.1 kg; BMI 29.0+/-0.9 kg.m-2) energy intake was fixed at 6 MJ.day-1 (their normal energy intake at that time) or 4 MJ.day-1 (low energy intake). In both studies, the effect of one week of fibre supplementation (40 g in study 1 and 20 g in study 2) was compared with no supplementation. In study 1, mean energy intake decreased significantly from 6.7+/-0.4 MJ to 5.4+/-0.2 MJ daily after fibre supplementation, while hunger and satiety scores did not change. At a low energy intake level of 4 MJ given in study 2, hunger scores were significantly decreased after fibre supplementation. No changes were seen in hunger and satiety scores during fibre supplementation at 6 MJ. The reduction in energy intake by soluble fibre under free living conditions and the hunger-reducing effect of fibre at the low energy intake level (4 MJ) suggests that fibre may be useful in the treatment of obesity, by facilitating compliance to low energy intake.

The effectiveness of long-term fibre supplementation on weight maintenance in weight-reduced women.

OBJECTIVE: To investigate whether fibre supplementation is effective in weight-reduced subjects for maintenance of weight-loss in the long-term. DESIGN: Longitudinal, randomly assigned intervention study with supplementation of 20 g of water soluble fibre (guar gum) daily for 14 months after an energy-restricted period of two months (VLCD). SUBJECTS: Thirty-one female, obese subjects (age: 41.4 +/- 7.4 y: BMI 33.2 +/- 3.7 kg/m-2); 20 subjects were supplemented with fibre and 11 subjects served as the control group. MEASUREMENTS: Body weight (BW), blood lipids and blood pressure, anthropometry, and eating behaviour were measured before the VLCD (0), after VLCD (2), and at 4, 10, and 16 months. RESULTS: The fibre group with at least 80% compliance (group A) and the control group showed the same weight regain response after VLCD. The fibre consuming group with 50-80% compliance (group B) differed with respect to relapse. The rate and amount of BW regain was significantly higher for group B. After 14 months group B had returned to baseline levels, whereas group A and the control group showed a tendency to a lower BW than at baseline (P = 0.09). No effect of fibre supplementation was found on blood lipids, blood pressure and energy intake. Eating behaviour characteristics changed during the intervention and might explain differences in weight maintenance. CONCLUSIONS: No effect of 14 months fibre supplementation was found on weight maintenance in weight-reduced subjects. Guar gum intake did not result in reduction of blood pressure or cholesterol, or in suppression of energy intake.

The effectiveness of long-term supplementation of carbohydrate, chromium, fibre and caffeine on weight maintenance.

OBJECTIVE: To investigate whether supplementation of carbohydrate, chromium, dietary fibre and caffeine is effective for maintenance of weight-loss in the long-term. DESIGN: A longitudinal, double-blind, randomly assigned intervention study of 16 months with supplementation of either 50g of carbohydrates (CHO), 200 micrograms chromium-picolinate (Cr-Pic), 20g of soluble fibre plus 100 mg caffeine (CHO+) or 50g of plain CHO, for 16 months besides a very low energy diet (VLED) during the first two months. SUBJECTS: Thirty-three female obese subjects (age, 34.8 +/- 7.0 y; body weight (BW): 85.5 +/- 10.0 kg; body mass index (BMI) 31.2 +/- 3.7 kg.m-2) participated, 13 subjects were supplemented with CHO+, 11 subjects were supplemented with CHO and 9 subjects served as a control group. MEASUREMENTS: SW, body composition, energy intake and blood parameters were measured before the VLED (0), after the VLED at 2 months (2), and at 4, 10 and 16 months. RESULTS: The amount and course of relapse of BW was equal for the supplemented and control groups. The average regain at 16 months (the weight gained as a percentage of the total weight loss during the VLED) was 66.1 +/- 81.2%, and was not different between the groups. No differences in body composition were found between the groups at 16 months. The CHO supplements resulted in significantly elevated energy percentage (En %) intake of CHO daily, in both supplemented groups, although this did not result in less regain. Pearson correlation analysis for all subjects revealed that the more fat consumed, the more regain was found at 16 months (r = 0.41, P < 0.05). A high CHO consumption was correlated with less regain (r = -0.40, P = 0.05). Furthermore, chromium intake did not result in significant changes in blood parameters and body composition. CONCLUSION: Although additional supplementation of CHO, chromium, dietary fibre and caffeine intake did not affect BW, the En % CHO daily was increased significantly. Our results indicate that a high En% intake of CHO and a low En% intake of fat daily is beneficial for prevention of weight regain.

Energy intake adaptation of food intake to extreme energy densities of food by obese and non-obese women.

OBJECTIVE: Examination of energy intake in relation to energy density of food in obese and non-obese women. Assessment of energy and macronutrient intake over a day. DESIGN: Controlled food intake diaries of two weekdays and one weekend day. SETTING: Daily life, with visits to the department of Human Biology, State University of Limburg. SUBJECTS: 96 women: 68 subjects: 34 obese and 34 non-obese were matched for age (20-50y) and were selected based on completing the food intake diaries accurately, i.e. underreporting < 10% of their estimated energy intake. RESULTS: The obese women showed a food intake distribution of 24 en% (0-7.5 kJ/g), 52 en% (7.5-15 kJ/g) and 24 en% (15-22.5 kJ/g), with a macronutrient composition of C/P/F: 39/17/44 en%. (Significantly different from the values of non-obese (P = 0.007) and of the Dutch food guidelines values (P = 0.008)). Non-obese women showed a food intake distribution of 38 en% (0-7.5 kJ/g), 49 en% (7.5-15 kJ/g), 13 en% (15-22.5 kJ/g), with a macronutrient composition of C/P/F: 46/17/37 en%. Energy intake per meal increased from 1.2 or 1.3 MJ to 4.1 or 4.5 MJ over a day. CONCLUSIONS: In obese women food intake was adapted to extreme energy densities of the food and in non-obese women food intake was overadapted to extreme energy densities. Energy intake per meal increased during the day.

The effect of different dosages of caffeine on endurance performance time.

The effect of different dosages of caffeine (0-5-9-13 mg.kg body weight-1) on endurance performance was examined. Nine well-trained cyclists participated in this study (VO2max 65.1 +/- 2.6 ml.kg-1.min-1). Caffeine capsules were administered in random order and double-blind. One hour after capsule ingestion, subjects cycled until exhaustion at 80% Wmax on an electromagnetically braked cycle ergometer. Blood samples were taken before, during and after the exercise test. Before and after the test a urine sample was obtained. A significant increase in endurance performance was found for all caffeine tests compared to placebo (endurance time 47 +/- 13, 58 +/- 11, 59 +/- 12 and 58 +/- 12 min for 0, 5, 9 and 13 mg.kg-1 body weight, respectively). No differences were found in endurance performance between the three caffeine dosages which indicates that no dose-response relation of caffeine and endurance performance was found. An increased free fatty acid and glycerol concentration was found after caffeine consumption compared with placebo. The mean urinary caffeine concentrations after exercise were 4.8 +/- 1.8, 8.9 +/- 5.2 and 14.9 +/- 6.9 micrograms.ml-1 urine for 5, 9 and 13 mg of caffeine.kg-1 body weight. Only the lowest dose of caffeine resulted in urine caffeine concentrations below the doping limit of the International Olympic Committee of 12 micrograms.ml-1 urine in all individuals. It is concluded that caffeine is an ergogenic aid that stimulates endurance performance. A dose-response relation between caffeine and endurance time was not found for the dose-range investigated.(ABSTRACT TRUNCATED AT 250 WORDS)