Acute Metabolic And Endocrine Responses Of Fructose And Glucose In Healthy Subjects

Background and aim:The relationship between fructose and metabolic disorder and CVD risk has gained increased interest in recent years. No related clinical study has been reported in China. The aim of the present study was to investigate the different acute metabolic and endocrine responses of dietary fructose or glucose.Method:This was a randomized, crossover and double-blinded postprandial trial. Twenty healthy young subjects aged 23.5y (10 males and 10 females) were recruited in Hangzhou, China. All volunteers were randomized to two groups (A and B):after an 8-h overnight fasting, subjects either ingested 300 mL of 22.5% glucose (group A) or fructose (group B) solution at 0830 within 5 minutes. After one-week washout period, volunteers were crossed over to the other group. During each intervention, venous blood was collected at Oh,0.5h, lh,2 h and 3h. Blood pressure was measured at Oh, 1h,2h and 3h.Result:There were 18 subjects who completed the study. In glucose, serum glucose concentration in serum significantly increased from baseline at 0.5h and 1h (p<0.01 and p<0.001); insulin concentration significantly increased from baseline in glucose at 0.5h, 1h and 2h (p<0.001, p≤0.05 and p≤0.01); insulin-c significantly increased from baseline in glucose at 0.5h, 1h and 2h 3h (p<0.001, p≤0.001and p<0.05). In fructose, serum glucose and C-peptide did not vary significantly from baseline; both insulin and C-peptide significantly rose at 1h (p≤0.05 and p≤0.05).3h-AUC of serum glucose, insulin and C-peptide were significantly lower in fructose than glucose (p≤0.001, p≤0.001 and p≤0.001).AG, TC, LDL-C, HDL-C in both glucose and fructose did not vary significantly from baseline.3h-AUC of TAG, TC, LDL-C, HDL-C did not differ between fructose and glucose. In fructose, nitric oxide concentration in serum significantly decreased from baseline at 1h and 2h (p≤0.05 and p≤0.05); serum uric acid concentration increased significantly from baseline at 1h and 2h (p≤0.05 and p≤0.05); systolic blood pressure increased significantly from baseline at lh (p≤0.05); diastolic blood pressure did not vary significantly from baseline. In glucose, nitric oxide, serum uric acid, systolic blood pressure, diastolic blood pressure did not differ significantly.3h-AUC of NO was significantly lower after ingesting fructose than glucose (p≤0.05); 3h-AUC of SUA, SBP were significantly higher in fructose than glucose (p≤0.05 and p<0.05).3h-AUC of DBP was not different between fructose and glucose.In glucose, serum phosphofructokinase level increased at 1h (p≤0.01); aldose reductase level did not differ significantly. In fructose, LDH level increased significantly at lh and 2h (p≤0.05 and p≤0.05); AR level significantly increased at lh (p≤0.05).3h-AUC of AR was significantly higher in fructose than glucose (p≤0.05); 3h-AUC of LDH was significant higher in fructose than glucose.3h-AUC of PFK was significant lower in fructose than glucose (p≤0.01).Conclusion:Fructose and glucose had different acute effects on metabolic and CVD parameters and an underlying causation between fructose and hypertension via endothelial dysfunction may exist.