PHYSIOLOGICAL ACTIVITY OF AUTOPHAGY IN RESTRICTING CALORIE INTAKE AMONG MEN

Abstract

In a group of healthy men of different ages (18–75 years old), the level of autophagy marker – Beclin-1 in the initial state and after a course (on the 12th day) of limited (800–1200 kcal) calorie restriction (CR) was studied by the enzyme immunodetection. Body composition was determined using impedansometry. The degree of autophagy activation was assessed by the «delta» value – the difference between the initial concentration and after CR. Normally, men showed significant variability in the level of Beclin-1 from 6.14 to 844.78 pg / ml. As a result of the CR course, there was a significant decrease in body weight, soft lean, fat and muscle mass (p<0.0001), as well as intracellular water (p<0.006). As a result of the course of CR in the entire group, an increase of 2.0 times (p<0.01) in the concentration of Beclin-1 was noted. At the same time, positive correlations were revealed in the entire study group between weight, body mass index (r = 0.46 and r = 0.48, respectively, p<0.05), fat mass (r = 0.62; p<0,01). The same patterns were observed in middle-aged people. A direct correlation was found in obese individuals between the level of Beclin-1 and the content of fat mass. In the group of young people, positive correlations between the Beclin-1 delta and the delta of individual body composition indicators were revealed: muscle (r = 0.96; p<0.05), soft lean (r = 0.96; p<0.05) weight and total water (r = 0.96; p<0.05). The loss of these body components was accompanied by a parallel decrease in the activity of Beclin-1. In old age, fat loss occurred in parallel with an increase in Beclin-1 activity (r = -0.87; p<0.05), directly correlated with HDL (r = 0.94; p<0.01) and inversely correlated with LDL (r = -0.99; p<0.01) and total cholesterol (r = -0.98; p<0.01). In young people, the opposite pattern was observed. Each age group had its own characteristics in the ratios of the studied parameters.