Increased fructose concentrations in blood and urine in patients with diabetes.
OBJECTIVE
To investigate fructose metabolic changes in patients with diabetes.


METHODS
Serum and urinary fructose concentrations were determined in healthy subjects (n = 23) and in nondiabetic (n = 23) and diabetic patients (n = 26). Fructose was measured using our newly developed method, and (13)C(6)-fructose was used as the internal standard. After adding sample to a fixed amount of internal standard, ion-exchange resins and high-performance liquid chromatography pretreatments were performed. Then, the amount of fructose in the sample was measured by gas chromatography-mass spectrometry.


RESULTS
Serum fructose concentrations in patients with diabetes (12.0 +/- 3.8 micromol/l) were significantly higher than those in healthy subjects (8.1 +/- 1.0 micromol/l, P < 0.001) and nondiabetic patients (7.7 +/- 1.6 micromol/l, P < 0.001), and daily urinary fructose excretion was significantly greater in patients with diabetes (127.8 +/- 106.7 micromol/day) than in nondiabetic patients (37.7 +/- 23.0 micromol/day, P < 0.001). In patients with diabetes (n = 20), serum fructose concentrations (8.6 +/- 1.8 micromol/l, P < 0.001) and daily urinary fructose excretion (63.4 +/- 63.8 micromol/day, P < 0.01) significantly decreased by week 2 after admission.


CONCLUSIONS
The present results differed from those of previous studies in that we found that the serum and urinary fructose concentrations decreased rapidly, concomitant with an improvement in glycemia. Therefore, hyperglycemia was associated with increased serum and urinary fructose concentrations in patients with diabetes.
Kawasaki
Takahiro
T
Department of Internal Medicine, Teikyo University, School of Medicine, 11-1, 2-chome Kaga, Itabashi-ku, Tokyo, Japan 173-0003. t-kawa@med.teikyo-u.ac.jp
Akanuma
Hiroshi
H
Yamanouchi
Toshikazu
T
D000328:Adult; D000368:Aged; D003920:Diabetes Mellitus / Q000097:blood* / Q000652:urine*; D005215:Fasting; D005260:Female; D005632:Fructose / Q000097:blood* / Q000652:urine*; D006760:Hospitalization; D006801:Humans; D006943:Hyperglycemia / Q000097:blood / Q000652:urine; D008297:Male; D008875:Middle Aged
D005632:Fructose