EFFECT OF EXERCISE TRAINING ON THE CAPACITY OF HDL TO RECEIVE UNESTERIFIED AND ESTERIFIED CHOLESTEROL AND ON PARAOXONASE 1 ACTIVITY IN AGED INDIVIDUALS

Background and Aims : Aim: To investigate influence of exercise training on cholesterol transfer to HDL and paraoxonase 1 (PON1) activity in aged individuals.Methods: 43 aged individuals were enrolled in two groups according their self-reported exercise training history: 22 exercised (13 males, 67 ± 6 yrs) and 21 non-exercised (9 males, 68 ± 5 yrs). PON1 activity was measured by p-nitrophenol consumption method. Cholesterol transfer to HDL was performed by incubating plasma with a donor lipoprotein-like nanoparticle containing radioactively labeled unesterified (UC) and esterified cholesterol (EC), followed by chemical precipitation and radioactive count. All subjects performed cardiopulmonary test to determine VO2 peak.Results: Body-mass index (28.1 ± 4.8 kg/m2 vs. 24.7 ± 2.8 kg/m2; p=0.0072) and waist circumference (95 ± 10 cm vs. 87 ± 10 cm; p=0.0135) were lower and VO2 peak was higher in the exercised (27.3 ± 5.9 ml/kg/min vs. 32.7 ±5.0 ml/kg/min; p=0.0024) than in non-exercised group. HDL-C (51 ± 14 mg/dL vs. 68 ±14 mg/dL; p=0.0002), apo A-I (1.5 ± 0.3 g/L vs. 1.7 ± 0.2 g/L; p= 0.0420), PON1 activity (65 ± 48 U/L vs. 84 ± 33 U/L; p=0.0477) were also higher in exercised group. In respect to cholesterol transfer, both EC (4.2 (3.2:5.9) % vs. 4.7 (3.6:5.5) %; p=0.0477) and UC (5.5 (3.8:8.2) % vs. 6.4 (4.8:8.9) %; p=0.0026) were greater in the exercised than in non-exercised.Conclusions: Conclusion: Exercise training not only increased HDL-C but also improved protective HDL functions such as capacity to receive both forms of cholesterol and HDL-associated PON1 activity. Background and Aims : Aim: To investigate influence of exercise training on cholesterol transfer to HDL and paraoxonase 1 (PON1) activity in aged individuals. Methods: 43 aged individuals were enrolled in two groups according their self-reported exercise training history: 22 exercised (13 males, 67 ± 6 yrs) and 21 non-exercised (9 males, 68 ± 5 yrs). PON1 activity was measured by p-nitrophenol consumption method. Cholesterol transfer to HDL was performed by incubating plasma with a donor lipoprotein-like nanoparticle containing radioactively labeled unesterified (UC) and esterified cholesterol (EC), followed by chemical precipitation and radioactive count. All subjects performed cardiopulmonary test to determine VO2 peak. Results: Body-mass index (28.1 ± 4.8 kg/m2 vs. 24.7 ± 2.8 kg/m2; p=0.0072) and waist circumference (95 ± 10 cm vs. 87 ± 10 cm; p=0.0135) were lower and VO2 peak was higher in the exercised (27.3 ± 5.9 ml/kg/min vs. 32.7 ±5.0 ml/kg/min; p=0.0024) than in non-exercised group. HDL-C (51 ± 14 mg/dL vs. 68 ±14 mg/dL; p=0.0002), apo A-I (1.5 ± 0.3 g/L vs. 1.7 ± 0.2 g/L; p= 0.0420), PON1 activity (65 ± 48 U/L vs. 84 ± 33 U/L; p=0.0477) were also higher in exercised group. In respect to cholesterol transfer, both EC (4.2 (3.2:5.9) % vs. 4.7 (3.6:5.5) %; p=0.0477) and UC (5.5 (3.8:8.2) % vs. 6.4 (4.8:8.9) %; p=0.0026) were greater in the exercised than in non-exercised. Conclusions: Conclusion: Exercise training not only increased HDL-C but also improved protective HDL functions such as capacity to receive both forms of cholesterol and HDL-associated PON1 activity.