INCREASED URINARY POLYAMINE EXCRETION AFTER STARTING A VERY-LOW-CALORIE DIET

Urinary polyamine excretion has been suggested to reflect hypermetabol ism or catabolism in different illnesses. In the present study, the ex cretion of urinary polyamines was examined in 12 obese subjects (3 men , 9 women aged 32-55 y, body mass index 33.3-64.7 kg m(-2)) before and during a very low calorie diet (the total calorie intake 2100-3350 kJ ). In addition, nitrogen balance, basal energy expenditure (BEE) and s erum thyroid hormone levels were examined. During the first week on a very low calorie diet (VLCD) the mean body weight declined from 121.8/127.3 to 117.4+/-26.2 kg (mean+/-SD, p<0.001), and after 12 weeks of treatment body weight was 106.6+/-24.6 kg. Immediate reduction of BEE from 1.44+/-0.24 to 1.34+/-0.24 kcal min(-1) (p<0.001) was found withi n the first week of therapy and BEE measured on weight-maintaining die t remained lower at 12 weeks (1.25+/-0.27 kcal min(-1), p<0.01). Serum free T3 decreased and reverse T3 increased significantly after starti ng VLCD. Nitrogen balance remained negative during the first 2 weeks o n VLCD. A significant increase in total (38%), and in N1-acetyl- and N 8-acetylspermidine excretions in the urine (40% and 27%, respectively, p<0.05) was found during the first week, but later on the levels were not significantly different from the baseline levels. The changes in free T3 and reverse T3 showed moderate correlations with the changes i n N1-acetylsperrnidine (r = -0.59 and r = 0.55, respectively, p less t han or equal to 0.05), and N8-acetylspermidine excretion rates (r = -0 .63, p<0.05 and r = 0.47, N.S.). The present results suggest that duri ng a very low calorie diet increased urinary acetylpolyamine excretion is a marker of catabolism.