Differences In Postprandial Levels Research Articles

Effects of Multiple Sedentary Days on Metabolic Risk Factors in Free-Living Conditions: Lessons Learned and Future Recommendations.

Background: Recent experimental studies in adults have demonstrated that interruptions to prolonged sitting have beneficial effects on metabolic risk factors in adults, compared to prolonged sitting. We explored the hypothesis that multiple consecutive days of predominantly prolonged sedentary time may have an unfavorable effect on the postprandial response of C-peptide, glucose, and triglycerides in free-living healthy young men.Methods: In this explorative pilot study, healthy young men (n = 7; 18–23 years) consumed standardized mixed meals at 1 and 5 h during two experimental laboratory-sitting days, with 6 days of predominantly prolonged sedentary time in between. Serum and plasma samples were obtained hourly from 0 to 8 h for measurement of glucose, C-peptide, and triglycerides. Participant's sedentary time was monitored using an accelerometer during the prolonged sedentary days as well as during 6 normal days prior to the first laboratory day. Differences in postprandial levels were assessed using generalized estimating equations analysis. Due to the explorative nature of this study and the small sample size, p-value was set at <0.10.Results: Overall, when expressed as % of wear time, sedentary time was 5% higher during the 6 prolonged sedentary days, which was not significantly different compared to the 6 normal days (n = 4). Following 6 prolonged sedentary days, postprandial levels of C-peptide were significantly higher than at baseline (B = 0.11; 90%CI = [0.002; 0.22]; n = 7). Postprandial levels of glucose and triglycerides were not significantly different between the 2 laboratory days.Conclusions: Due to the relatively high sedentary time at baseline, participants were unable to increase their sedentary time substantially. Nevertheless, postprandial C-peptide levels were slightly higher after 6 prolonged sedentary days than after 6 normal days.

Post-prandial anorexigenic gut peptide, appetite and glucometabolic responses at different eating rates in obese patients undergoing laparoscopic sleeve gastrectomy.

Although different hypotheses have been proposed, the underlying mechanism(s) of the weight loss induced by laparoscopic sleeve gastrectomy (LSG) is still unknown. The aim of this study was to determine whether eating the same meal at different rates (fast vs. slow feeding) evokes different post-prandial anorexigenic gut peptide responses in ten obese patients undergoing LSG. Circulating levels of GLP-1, PYY, glucose, insulin and triglycerides were measured before and 3months after LSG. Visual analogue scales were used to evaluate the subjective feelings of hunger and satiety. Irrespective of the operative state, either fast or slow feeding did not stimulate GLP-1 release (vs. 0min); plasma levels of PYY were increased (vs. 0min) by fast and slow feeding only after LSG. There were no differences in post-prandial levels of GLP-1 when comparing fast to slow feeding or pre-to-post-operative state. Plasma levels of PYY after fast or slow feeding were higher in post, rather than pre-operative state, with no differences when comparing PYY release after fast and slow feeding. Hunger and satiety were decreased and increased, respectively, (vs. 0min) by food intake. Fast feeding evoked a higher satiety than slow feeding in both pre- and post-operative states, with no differences in hunger. In both pre- and post-operative states, there were similar responses for hunger and satiety after food intake. Finally, LSG improved insulin resistance after either fast or slow feeding. These (negative) findings would suggest a negligible contribution of the anorexigenic gut peptide responses in LSG-induced weight loss.

Changes in serum lipids and blood glucose in non diabetic patients with metabolic syndrome after mixed meals of different composition.

Aims. To investigate the postprandial changes in serum lipoproteins and blood glucose and to verify whether different nutrient composition of the meal elicits different response in patients with (MetS+) and without (MetS−) metabolic syndrome. Research Design and Methods. 50 MetS+ patients and 50 age- and sex-matched MetS− consumed a regular lunch chosen among those more similar to their usual diet. Blood was drawn in the morning after 12-hour fasting and 2 and 4:30 hours after the meal. Results. Serum triglycerides increased more in MetS+ (35%, 4:30 hours after the meal) than in MetS− (29%), HDL-cholesterol decreased 2 hours after the meal in both groups (−4% and −5%, resp.). Blood sugar similarly increased in both groups (19%, 2 hours after the meal in MetS+ and 17% in MetS−) and plasma insulin increased more and remained high longer in MetS+ (73.5 and 52.3 μU/mL, 2 and 4:30 hours after the meal) than in MetS− (46.7 and 21.6 μU/mL). Difference in nutrient composition of the meal (carbohydrate 57%, fat 28% versus carbohydrate 45%, fat 35%) was not associated with differences in postprandial levels of triglycerides, HDL-cholesterol, glucose, and insulin within each group. Conclusions. As compared with MetS−, MetS+ patients show a greater hypertriglyceridemic and hyperinsulinemic response to a regular lunch whatever the carbohydrate or fat content of the meal.

Impact of Sustained Weight Loss Achieved through Roux-en-Y Gastric Bypass or a Lifestyle Intervention on Ghrelin, Obestatin, and Ghrelin/Obestatin Ratio in Morbidly Obese Patients

BackgroundAppetite-regulating hormones seem to play an important role in weight loss after bariatric surgery. Less is known regarding long-term weight loss maintenance. The objective of the study was to evaluate ghrelin and obestatin levels following long-term weight loss achieved through bariatric surgery or a lifestyle intervention in morbidly obese patients.MethodsThe study was cross-sectional in design carried out in a university research center setting. The participants were weight-stable morbidly obese patients who had undergone, on average, 3 years ago, Roux-en-Y gastric bypass (RYGB) surgery (n = 9) or a lifestyle weight loss intervention (n = 8), and patients on a waiting list for bariatric surgery (control group; n = 9). The main outcome measures were fasting/postprandial plasma levels of total ghrelin and obestatin and ghrelin/obestatin ratio.ResultsFasting ghrelin and obestatin plasma levels were significantly elevated in the RYGB, but not in the lifestyle group, as compared with the control group. There was no statistical significant difference in fasting ghrelin/obestatin ratio among study groups. Ghrelin levels were suppressed after breakfast in all groups, with no significant differences in postprandial levels overtime between them. Obestatin levels did not change postprandially in any of the groups, but the area under the curve was significantly higher in the RYGB than in the control group.ConclusionsSustained weight loss maintenance seems to be associated with increased fasting levels of ghrelin and obestatin after RYGB surgery, but not after a lifestyle intervention, while maintaining ghrelin/obestatin ratio. Ghrelin is, therefore, unlikely to contribute to weight loss maintenance after RYGB, and other mechanisms are probably involved.

Reduced serum cholecystokinin response to food intake in female athletes

Strenuous training in women has been shown to cause menstrual dysfunction and decreased bone mineral density. These endocrine and metabolic complications are associated with an insufficient dietary intake and decreased body fat content in female athletes. The present investigation was undertaken to study serum levels of cholecystokinin (CCK), insulin, gastrin, and cortisol in 14 female long-distance runners and 15 sex- and age-matched control subjects during intake of a standardized meal (500 kcal). The athletes showed a decreased response of the “satiety peptide” CCK to the meal and reported increased hunger compared with the control group. Meal-related insulin response was also decreased in the athletes, whereas gastrin levels were comparable to those of controls. Basal levels of glucose were increased in the athletes, but there was no difference in postprandial levels between the groups. Cortisol levels were clearly elevated in the female runners. We conclude that insufficient food intake in female athletes cannot be explained by increased CCK secretion and satiety. Since the athletes reported a larger caloric intake of a normal daily breakfast than the control subjects, the decreased CCK response may instead be explained by an adaptation to increased food intake. The decreased meal-related insulin response may be a reflection of increased insulin sensitivity as an adaptation to physical exercise. However, an impaired peptide secretion cannot be excluded. The role of elevated cortisol levels in the gastrointestinal hormone response needs further investigation.

Adult Cystic stic Fibrosis: Postprandial Response of Gut Regulatory Peptides

Responses of 11 gastrointestinal regulatory peptides to a standard test meal were assessed in 10 adult patients with cystic fibrosis. The basal plasma neurotensin was significantly elevated in patients with cystic fibrosis, being 31.5 +/- 6.1 pmol/L compared with a control value of 10.3 +/- 1.5 pmol/L (p less than 0.005). Plasma neurotensin remained elevated throughout the test period. Basal plasma enteroglucagon was similarly elevated, the patients with fibrocystic disease having levels of 51.3 +/- 4.6 pmol/L compared to controls with levels of 33.2 +/- 6.7 pmol/L (p less than 0.02). There was, however, no significant difference in postprandial levels of plasma enteroglucagon. Postprandial motilin was significantly elevated in the patients with cystic fibrosis; this elevation is in contrast with previous findings in children. Release of gastric inhibitory polypeptide was impaired, while release of cholecystokinin showed no significant difference in control values, although there was a tendency for delay. There was no significant postprandial rise of pancreatic polypeptide in the patients, whose levels were grossly lower than controls. Insulin showed a delayed response. No significant differences were observed between patients and controls in levels of gastrin, pancreatic glucagon, somatostatin, or vasoactive intestinal peptide. The elevation of plasma neurotensin and enteroglucagon in the basal state may reflect an adaptive response and may be part of the improved digestive function in adults compared with children with fibrocystic disease.