Do PON1-Q192R and PON1-L55M polymorphisms modify the effects of hypoxic training on paraoxonase and arylesterase activity?

BACKGROUND: Low levels of antioxidant paraoxonase 1 (PON1) enzyme activity, PON1-Q192R polymorphism (a glutamine (Q) to arginine (R) substitution at position 192), PON1-L55M polymorphism (a leucine (L) to methionine (M) substitution at position 55), and oxidized low-density lipoprotein (oxLDL) are risk factors for coronary heart disease. Aerobic exercise improves PON1 activity, but the effects of hypoxic exercise are yet unclear. The aim of this study was to determine the effects of hypoxic underwater rugby training on PON1 activity and oxLDL levels and the role of the mentioned polymorphisms. METHODS: Serum PON1 and arylesterase activities (ARE), PON1, PON3, and oxLDL protein levels (by using the enzyme-linked immunosorbent assays) were determined in an athletic group (42 trained male underwater rugby players; age = 21.7 ± 4.2 years, mean ± SD) and a control group (43 sedentary men; age = 23.9 ± 3.2 years). The polymorphisms were determined from genomic DNA samples. RESULTS: PON1 activity (25.1%, p = 0.052), PON3 (p < 0.001), and oxLDL (p < 0.001) of the athletic group, including most genotype groups, were higher than those of the control group. In comparison to the controls, PON1 activity levels (p = 0.005) of the PON1-Q192R homozygote QQ genotype group and PON1 activity levels (30%, p = 0.116) of the PON1-L55M homozygote LL genotype group were higher, whereas ARE activity values of athletic R allele carrier (Rc = QR + RR) (p = 0.005) and LL group (p = 0.002) were lower than the control genotype groups related to their polymorphisms. CONCLUSION: Hypoxic training can cause (1) significant oxidative stress, including oxLDL, and an antioxidant response (increase in PON1 activity and PON3), (2) differences in the activity of PON1 and ARE, which are modified by PON1-Q192R and PON1-L55M polymorphisms, respectively, and (3) improvements in PON1 activity of QQ and LL groups. However, hypoxic training can cause a disadvantage of LL and Rc groups for ARE.

Does the TMPRSS6 C > T Polymorphism Modify the Endurance Training Effects on Hematological Parameters?

This study investigated the role of TMPRSS6 C > T polymorphism (TMPRP) on the effects of chronic aerobic training on main hematological parameters in male soccer referees, which is yet unknown. Two groups composed of total of 45 healthy male soccer referees and 42 sedentary were compared for hemogram, serum hepcidin, ferritin, and iron levels. TMPRP was determined from genomic DNA samples. Participants' physical and physiological (Yoyo endurance level-2 test) measurements were carried out. The athletic T carrier (Tc = TT + TC) group RBC count was significantly higher than the control (p < 0.01), whereas the athletic CC homozygous group serum iron and transferrin saturation (TS) were lower than the control depending on the TMPRP. The ferritin and iron values of the athletic Tc group were higher than of the athletic CC group (29.2% and 14.1%, respectively; p > 0.05) although the control Tc group RBC (p < 0.05) and iron (23.8%, p > 0.05) values were lower than the control CC due to genetic tendency. The training did not change hepcidin levels. These results suggest that the TMPRP can modify the endurance training effects on iron and TS levels and RBC count (in the CC and Tc groups) respectively. The CC group may be adversely affected for iron and TS from endurance trainings. It may be recommended that the training programs should be organized according to phenotype characteristics.

The effects of regular aerobic exercise training on blood nitric oxide levels and oxidized LDL and the role of eNOS intron 4a/b polymorphism.

BACKGROUND: Nitric oxide (NO), oxidized LDL (OxLDL) and endothelial nitric oxide synthase intron 4a/b polymorphism (eNOSP) are related to atherosclerosis (AS). The present study investigated the effects of regular aerobic exercise training on the mentioned risk factors as well as blood lipids and lipoproteins (BLLPs) and the role of eNOSP, which is unclear. METHODS: The study was participated by 46 well trained male soccer referees as the athletic group (AG, age; 23.26 ± 2.84 years) and 43 sedentary controls (CG, age; 23.16 ± 3.28 years). Yoyo intermittent endurance (Yoyo IE-2 test) was performed to measure aerobic endurance levels of the participants. Serum NO, eNOS and oxidized LDL (OxLDL) levels (by ELISA method) and total oxidant /antioxidant status ratio (/TOS/TAS) as oxidative stress (OS) index (OSI) and BLLPs levels were determined. eNOSP was identified from genomic DNA samples with VNTR analysis. RESULTS: There is no significant difference between AG and CG including the genotype groups for NO, eNOS and BLLPs and eNOSP has no role. However, AG's NO (29%, p > .05) and TAS levels were significantly higher (p = .001) than those of CG, whereas OSI (p = .001) and OxLDL (p = .011) values were significantly lower. On the other hand, NO value of the athletic bb group was 29% higher compared with the control and the a carrier (aC = aa + ab) group. CONCLUSIONS: These findings suggest that regular aerobic exercise improves blood NO levels and antioxidant capacity, while decreasing OS levels including OxLDL, but not eNOS and BLLPs in the athletes. Although the polymorphism does not have a modifying effect on these effects, bb genotype group may benefit more from training for NO than aC group due to genetic tendency.