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We sought to delineate the effects of acute and chronic exercise on the regulation of intracellular nitric oxide (N[O.sub.i]) production in putative endothelial progenitor cells (EPCs). Putative EPC colony-forming units (CFU-EC) were cultured from blood drawn before and after 30 min of treadmill exercise at 75% of maximal oxygen uptake in active (n = 8) and inactive (n = 8) men. CFU-EC were similar between groups at baseline, but increased after exercise in active men only (P = 0.04). CFU-EC expressed Dower NADPH oxidase subunit [gp91.sup.phox] mRNA and elevated endothelial nitric oxide synthase mRNA in active relative to inactive men at baseline (P < 0.05). Acute exercise reduced [gp91.sup.phox] mRNA in CFU-EC of both groups (P < 0.05), whereas [p47.sup.phox] mRNA levels were reduced in the inactive group only (P = 0.02). There were no differences between groups or with acute exercise in xanthine oxidase, superoxide dismutase isoforms, or gluthathione peroxidase-1 mRNA levels. N[O.sub.i] was significantly greater in CFU-EC of active men at baseline (P = 0.004). N[O.sub.i] increased in CFU-EC of inactive men with acute exercise, and in vitro experiments with apocynin indicated the increased N[O.sub.i] production was caused by suppression of NADPH oxidase. However, the increases in N[O.sub.i] with the different treatments in the inactive group did not reach the baseline levels in the active group (P < 0.05). We conclude that acute exercise increases N[O.sub.i] in cells generated by the CFU-EC assay through an NADPH oxidase-inhibition mechanism in sedentary men. However, differences due to chronic exercise must involve additional factors. Our findings support exercise as a means to improve putative EPC function and suggest a novel mechanism that may explain this effect. physical activity; angiogenesis; oxidative stress doi: 10.1152/ajpheart.00347.2009.

In endothelial cells, [NF-[kappa]B is an important intracellular signaling molecule by which changes in wall shear stress are transduced into the nucleus to initiate downstream endothelial nitric oxide synthase (NOS3) gene expression. We investigated whether NF-[kappa] light-chain gene enhancer in B cells 1 (NFKB 1) promoter polymorphism ([sup.-94]NFKB1 I/D, where I is the insertion allele and D is the deletion allele) was associated with 1) NOS3 gene expression in endothelial cells under physiological levels of unidirectional laminar shear stress (LSS) and 2) endothelial function in prehypertensive and stage I hypertensive individuals before and after a 6-mo supervised endurance exercise intervention. Competitive EMSAs revealed that proteins present in the nuclei of endothelial cells preferentially bound to the I allele NFKB1 promoter compared with the D allele. Reporter gene assays showed that the I allele promoter had significantly higher activity than the D allele. In agreement with these observations, homozygous II genotype cells had higher p50 expression levels than homozygous DD genotype cells. Cells with the homozygous II genotype showed a greater increase in NOS3 protein expression than did homozygous DD genotype cells under LSS. Functional experiments on volunteers confirmed higher baseline reactive hyperemic forearm blood flow, and, furthermore, the subgroup analysis revealed that DD homozygotes were significantly less prevalent in the exercise responder group compared with II and ID genotypes. We conclude that the [sup.-94]NFKB1 I/D promoter variation contributes to the modulation of vascular function and adaptability to exercise-induced flow shear stress, most likely due to differences in NFKB1 gene transactivity. nuclear factor-[kappa] light-chain gene enhancer in B cells 1; nitric oxide synthase 3; shear stress

In its role as an endothelial cell proliferation and migration factor, vascular endothelial growth factor (VEGF) can affect peripheral circulation and therefore impact maximal oxygen consumption (V[O.sub.2 max]). Because of the role of VEGF, and because variation in the VEGF gene has the ability to alter VEGF gene expression and VEGF protein level, we hypothesized that VEGF gene polylnorphisms are related to VEGF gene expression in human myoblasts and V[O.sub.2 max] before and after aerobic exercise training. We analyzed the effects of the VEGF -2578/ -1154/-634 protnoter region haplotype on VEGF gene expression by using a luciferase reporter assay in cultured human myoblasts and found that the AAG and CGC haplotypes resulted m significantly higher hypoxia-stimulated VEGF gene expression than the AGG and CGG haplotypes. Consistent with these results, we found that individuals with at least one copy of the AAG or CGC haplotype had higher V[O.sub.2 max] before and after aerobic exercise training than did subjects with only the AGG and/or CGG haplotype. In conclusion, we found that VEGF-2578/-1154/-634 haplotype impacts VEGF gene expression in human myoblasts and is associated with V[O.sub.2 max]. These results have potential implications for aerobic exercise training and may prove relevant in the study of pathological conditions that can be affected by angiogenesis, such as coronary artery disease and peripheral artery disease. angiogenesis; exercise; genetics; polymorphism

This influence of long-term aerobic exercise practice on insulin functioning is measured in aged humans by the process of comparison of maximal responsiveness and insulin sensitivity. The measured values reveal that insulin sensitivity is increased considerably by the continuous practice of aerobic exercise. This indicates that regular aerobic exercise eliminates the occurrence of age-related enhancement in insulin resistance and abdominal obesity.

Investigating the extremes of the continuum of paracrine functions in CD34-/CD31+ CACs across diverse populations. Am J Physiol Heart Circ Physiol 312: H162-H172, 2017. First published October 28, 2016; doi:10.1152/ajpheart.00342.2016.--Paracrine function of circulating angiogenic cells (CACs) is thought to contribute to vascular maintenance. We previously identified S100A8 and S100A9 secreted from physically inactive individuals' CD34-/CD31+ CACs as negative regulators of capillary-like network formation. The purpose of this study was to investigate further the extremes of the continuum of CAC paracrine actions using two distinctly different groups representing "healthy" and "impaired" CAC function. We aimed to determine how capillary-like network formation in human umbilical vein endothelial cells (HUVECs) is affected by S100A8 and S100A9 in concentrations secreted by CACs from different ends of the health spectrum. CD34-/CD31+ CACs were isolated and cultured from 10 impaired function individuals defined as older (50-89 yr), non-ST-elevation myocardial infarction patients and 10 healthy individuals defined as younger (18-35 yr), healthy individuals, and conditioned media (CM) was generated. CM from the impaired function group's CACs significantly diminished network formation compared with CM from the healthy group (P<0.05). We identified elevations in S100A8, S100A9, and S100A8/A9 in the CM from the impaired function group (P<0.05). Pretreatment of HUVECs with inhibitors to a known S100A8 and S100A9 receptor, Toll-like receptor 4 (TLR4), but not receptor for advanced glycation end products, improved HUVEC network formation (P<0.05) compared with CM alone in the impaired function conditions. Exposure of HUVECs to the TLR4 signaling inhibitor also blocked recombinant S100A8- and S100A9-mediated reductions in network formation. Collectively, the results suggest that the mechanisms behind impaired CAC CD34-/CD31+ CM-mediated reductions in capillary-like network formation involve secretion of S100A8 and S100A9 and binding of these proteins to TLR4 receptors on HUVECs. [ABSTRACT FROM AUTHOR]

We aimed to determine if chronic endurance-exercise habits affected redox status and paracrine function of CD34+ and CD34-/CD31+ circulating angiogenic cells (CACs). Subjects were healthy, nonsmoking men and women aged 18-35 yr and categorized by chronic physical activity habits. Blood was drawn from each subject for isolation and culture of CD34+ and CD34-/CD31+ CACs. No differences in redox status were found in any group across either cell type. Conditioned media (CM) was generated from the cultured CACs and used in an in vitro human umbilical vein endothelial cell-based tube assay. CM from CD34+ cells from inactive individuals resulted in tube structures that were 29% shorter in length (P < 0.05) and 45% less complex (P < 0.05) than the endurance-trained group. CD34-/CD31+ CM from inactive subjects resulted in tube structures that were 26% shorter in length (P < 0.05) and 42% less complex (P < 0.05) than endurance-trained individuals. Proteomics analyses identified S100A8 and S100A9 in the CM. S100A9 levels were 103% higher (P < 0.05) and S100A8 was 97% higher in the CD34-/CD31+ CM of inactive subjects compared with their endurance-trained counterparts with no significant differences in either protein in the CM of CD34+ CACs as a function of training status. Recombinant S100A8/A9 treatment at concentrations detected in inactive subjects' CD34-/CD31+ CAC CM also reduced tube formation (P < 0.05). These findings are the first, to our knowledge, to demonstrate a differential paracrine role in CD34+ and CD34-/CD31+ CACs on tube formation as a function of chronic physical activity habits and identifies a differential secretion of S100A9 by CD34-/CD31+ CACs due to habitual exercise. [ABSTRACT FROM AUTHOR]

We investigated the influence of acute and chronic endurance exercise on levels of intracellular nitric oxide (NO), superoxide (Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed.), and expression of genes regulating the balance between these free radicals in CD34+ and CD34- peripheral blood mononuclear cells (PBMCs; isolated by immunomagnetic cell separation). Blood samples were obtained from age- and body mass index (BMI)-matched endurance-trained (n = 10) and sedentary (n = 10) men before and after 30 min of exercise at 75% maximal oxygen uptake (VO2max). Baseline levels of intracellu- lar NO (measured by DAF-FM diacetate) and Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed.) (measured by dihydroethidium) were 26% (P < 0.05) and 10% (P < 0.05) higher, respectively, in CD34+ PBMCs from the sedentary group compared with the endurance-trained group. CD34+ PBMCs from the sedentary group at baseline had twofold greater inducible nitric oxide synthase (iNOS) mRNA and 50% lower endothelial NOS (eNOS) mRNA levels compared with the trained group (P < 0.05). The baseline group difference in Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed.) was eliminated by acute exercise. Experi- ments with apocynin indicated that the training-related difference in Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed.) levels was explained by increased NADPH oxidase activity in the sedentary state, mRNA levels of additional angiogenic and anti- oxidant genes were consistent with a more angiogenic profile in CD34+ cells of trained subjects. CD34- PBMCs, examined for exploratory purposes, also displayed a more angiogenic mRNA profile in trained subjects, with vascular endothelial growth factor (VEGF) and eNOS being more highly expressed in trained subjects. Overall, our data suggest an association between the sedentary state and increased nitro-oxidative stress in CD34+ cells. [ABSTRACT FROM AUTHOR]

Perilipins are lipid droplet-coating proteins that regulate intracellular lipolysis in adipocytes. A haplotype of two perilipin gene (PUN) single nucleotide polymorphisms, 13041A>G and 14995A>T, has been previously associated with obesity risk. Furthermore, the available data indicate that this association may be modified by sex. We hypothesized that this haplotype would associate with body fatness, aerobic fitness, and a number of cardiovascular (CV) risk factor phenotypes before and after a 6-mo endurance exercise training program in sedentary older Caucasians. The major haplotype group (13041A114995A; n = 57) had significantly lower body mass index (BMI) and body fatness compared with noncarriers of the AA haplotype (n = 44) before the training intervention. Training improved body composition in both groups, but fatness remained higher in noncarriers than AA carriers after training. This fat retention in noncarriers blunted their maximal oxygen uptake (VO2max) adaptation to training. Female noncarriers had substantially higher concentrations of several conventionally and NMR-measured HDL-C subfractions than male noncarriers before and after training, but only minimal differences were found between the sexes in the AA haplotype group. Haplotype group differences in baseline and after-training responses to an oral glucose tolerance test (OGTT) also differed by sex, as noncarrier men had the highest baseline area under the insulin curve (insulin AUC), but were the only group to significantly improve insulin AUC with training. The insulin sensitivity index and plasma glucose responses to the OGTT were more favorable in AA carriers than noncarriers before and after training. Overall, our findings suggest that PUN variation explains some of the interindividual differences in the response of obesity and CV phenotypes to exercise training. Furthermore, these data contribute to the growing under- standing of PUN as a candidate gene for human obesity and the cardiometabolic consequences of excess adiposity. [ABSTRACT FROM AUTHOR]

Systemic oxidative stress plays a role in many degenerative diseases. Although regular physical activity has been known as the most effective nonpharmacological intervention to alleviate the oxidative stress, the beneficial effect varies between individuals. We investigated whether NADPH oxidase p22phox gene C242T and A640G polymorphisms are associated with systemic oxidative stress level response to exercise training (ExTr). Fifty-nine sedentary middle-aged to older Caucasians with relatively high cardiovascular disease risk factors underwent a 6-mo standardized ExTr program. Body mass index, plasma lipoprotein-lipid profiles, cardiovascular fitness, and plasma thiobarbituric acid reactive substances (TBARS) were measured before and after ExTr. Demographic and initial levels of cardiovascular disease risk factors were similar among genotype groups for both polymorphisms. Overall, TBARS was decreased by 16% with ExTr in the entire group (P < 0.001). There was no significant difference in TBARS changes with ExTr among the C242T genotype groups. However, A allele carriers showed greater reduction in TBARS than noncarriers at the A640G locus (P = 0.05). There was a significant interaction (P = 0.05) between ExTr and A640G polymorphism in TBARS changes with ExTr. This interaction remained after accounting for age and baseline TBARS level. Furthermore, diplotype analysis showed that TBARS was decreased to a greater extent in the C242/A640 haplotype carriers compared with the noncarriers (P < 0.05). We found that p22phox polymorphisms, especially A640G, were associated with differential changes in systemic oxidative stress with aerobic exercise training. [ABSTRACT FROM AUTHOR]

A polymorphism in the IL-6 gene, a G-to-C substitution 176 bp upstream of the ATG translation initiation site, has been associated with diabetes prevalence and insulin resistance. Interventions including exercise training are frequently used to modify cardiovascular disease risk factors. Consequently, this project examined associations between the IL-6 -174 genotype and oral glucose tolerance test outcomes in 50- to 75-yr-old sedentary men and postmenopansal women before and after aerobic exercise training. Among the 87 individuals who started the study, 56 were retested after 6 mo of aerobic exercise training. Subject characteristics at baseline did not differ between the IL-6 genotype groups with the exception of fasting glucose, which was higher (P = 0.02, covariates age, gender, and ethnicity) in the CC genotype group. The training-induced change in glucose area under the curve during the oral glucose tolerance test varied between the IL-6 -174 genotype groups (P = 0.05, covariates age, gender, ethnicity, baseline glucose area under the curve, and percent body fat change) with a significant decrease occurring only in the GG genotype group. Insulin outcomes did not differ among the groups at baseline or after training. Training-induced changes in weight, percent body fat, maximal oxygen consumption, fasting glucose, and an insulin sensitivity index also changed similarly among the genotype groups. In conclusion, fasting glucose and the extent to which glucose tolerance changes with exercise training may be influenced by the IL-6 -174 gene polymorphism. [ABSTRACT FROM AUTHOR]

Examines the association between genetic variations at the &Beta[sub2] and Β[sub3] adrenergic receptor gene loci and cardiovascular hemodynamics in postmenopausal women. Quantification of cardiac output; Interaction of genotype and habitual physical activity; Detection of the association.