Chemotherapy effect on arginine / citrulline cycle indicators in patients with acute myeloid leukemia and concomitant obesity

The aim of study was to investigate the changes in the arginine / citrulline cycle in patients with acute myeloid leukemia (AML) with concomitant obesity in dynamics of chemotherapy (CT). The study included 20 patients with newly diagnosed AML who had a body mass index (BMI) above 25. The average BMI was 29.35±0.93 kg/m2. Patients have undergone a course of remission induction CT "7+3" or "5+2". All patients were examined twice: before CT and on the 28th day. Complete blood test was assessed. Arginine and citrulline content, arginase and ornithine decarboxylase (ODC) activity were measured in the blood serum. The study results showed a 3-fold decrease in arginine content in the blood serum of patients with AML, as well as a 3.9-fold increase in arginase activity, 1.9-fold – ODC, 7.6-fold higher citrulline concentration compared with control (p<0.05). After CT, against the background of complete blood count normalization in AML patients with concomitant obesity, a 1.3-fold decrease in arginine concentration was noted, while the arginase activity increased by 2.2 times, ODC activity – by 1.8 times and citrulline content – by 2.4 times (р<0.05). After CT a high direct correlation between BMI and arginine concentration in AML patients with concomitant obesity (r=+0.63; p<0.05), as well as between the activity of ODC and arginine content (r=+0,55; p<0.05) was revealed. Thus, in AML patients with obesity prior to CT the disorders in the arginine / citrulline cycle were present, which are caused by oncohematological disease. Excess weight and obesity affect serum arginine levels, which may contribute to chemotherapy resistance.