Angiotensin II (AngII), via the AngII type 1 receptor (AT1R), contributes to oxidative stress. Aerobic exercise training (AEXT) reduces the risk of cardiovascular (CV) disease, presumably by reducing the grade of oxidative stress. We investigated the independent and combined influence of the AGTR1 A1166C and −825 T/A polymorphisms on oxidative stress and plasma AngII responses to AEXT in pre- and stage 1 hypertensives. Urinary 8-iso-PGF2α significantly increased with AEXT (p=0.002); however, there were no significant changes in superoxide dismutase activity or AngII levels. There was a significant difference in the change in AngII levels with AEXT between A1166C genotype groups (p=0.04) resulting in a significant interactive effect of the A1166C polymorphism and AEXT on the change in AngII (p<0.05). Only the TT genotype group of the −825 T/A polymorphism had a significant reduction in plasma AngII (p=0.02). Risk allele analysis revealed a significant reduction in plasma AngII (p=0.04) and a significant increase in urinary 8-iso-PGF2α (p=0.01) with AEXT in individuals with two risk alleles only. Our findings suggest that variation in the AGTR1 gene is associated with differential changes in plasma AngII but not oxidative stress.
AGTR1; angiotensin II; exercise; isoprostanes; oxidative stress
African Americans have the highest prevalence of hypertension in the world which may emanate from their predisposition to heightened endothelial inflammation. The purpose of this study was to determine the effects of a 6-month aerobic exercise training (AEXT) intervention on the inflammatory biomarkers interleukin-10 (IL-10), interleukin-6 (IL-6), and endothelial microparticle (EMP) CD62E+ and endothelial function assessed by flow-mediated dilation (FMD) in African Americans. A secondary purpose was to evaluate whether changes in IL-10, IL-6, or CD62E+ EMPs predicted the change in FMD following the 6-month AEXT intervention. A pre-post design was employed with baseline evaluation including office blood pressure, FMD, fasting blood sampling, and graded exercise testing. Participants engaged in 6 months of AEXT. Following the AEXT intervention, all baseline tests were repeated. FMD significantly increased, CD62E+ EMPs and IL-6 significantly decreased, and IL-10 increased but not significantly following AEXT. Changes in inflammatory biomarkers did not significantly predict the change in FMD. The change in VO2 max significantly predicted the change in IL-10. Based on these results, AEXT may be a viable, nonpharmacological method to improve inflammation status and endothelial function and thereby contribute to risk reduction for cardiovascular disease in African Americans.
This study investigated the effect of physical training and oxidative stress on the antioxidative activity and on plasma lipid profile. Forty eight rats were given either a physical training or no training for 4 weeks and were then subdivided into 3 groups: before-exercise (BE); during-exercise (DE); after-exercise (AE). The antioxidative activity was evaluated with the activities of catalase in plasma and superoxide dismutase (SOD), the ratio of reduced glutathione/oxidized glutathione (GSH/GSSG) and the level of malondialdehyde (MDA) in liver. The plasma concentrations of triglyceride (TG), total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-C)) were also compared. Compared to those of non-training group, catalase activities of training group were lower before exercise but higher during and after exercise. SOD activities were higher regardless of exercise. GSH/GSSG ratio was higher before exercise but was not significantly different during exercise and even lower after exercise. There were no differences between non-training group and training group in MDA levels regardless of exercise. Compared to those of non-training group, atherosclerotic index of training group was lower after exercise and there were no significant differences before and during exercise. There were no differences between non-training group and training group in HDL-C regardless of exercise. These results suggest that moderate physical training can activate antioxidant defenses and decrease the atherosclerotic index and this beneficial effect is evident under exercise-induced oxidative stress.
Physical training; exercise induced-oxidative stress; antioxidative enzyme activity; lipid profile
Oxidative stress that is mediated through NADPH oxidase activity plays a role in the pathology of hypertension, and aerobic exercise training reduces NADPH oxidase activity. The involvement of genetic variation in the p22phox (CYBA) subunit genes in individual oxidative stress responses to aerobic exercise training has yet to be examined in Pre and Stage 1 hypertensives.
Ninety-four sedentary Pre and Stage 1 hypertensive adults underwent 6 months of aerobic exercise training at a level of 70% V̇O2max to determine whether the CYBA polymorphisms, C242T and A640G, were associated with changes in urinary 8-iso-prostaglandin F2α (8-iso-PGF2α), urinary nitric oxide metabolites (NOx), and plasma total antioxidant capacity (TAC).
Demographic and subject characteristics were similar among genotype groups for both polymorphisms. At baseline, a significant (P = 0.03) difference among the C2424T genotype groups in 8-iso-PGF2α levels was detected, with the TT homozygotes having the lowest levels and the CC homozygotes having the highest levels. However, no differences were found at baseline between the A640G genotype groups. After 6 months of aerobic exercise training, there was a significant increase in V̇O2max (P < 0.0001) in the entire study population. In addition, there were significant increases in both urinary 8-iso-PGF2α (P = 0.002) and plasma TAC (P = 0.03) levels and a significant decrease in endogenous urinary NOx (P < 0.0001). Overall, aerobic exercise training elicited no significant differences among genotype groups in either CYBA variant for any of the oxidative stress variables.
We found that compared with CYBA polymorphisms C242T and A640G, it was aerobic exercise training that had the greatest influence on the selected biomarkers; furthermore, our results suggest that the C242T CYBA variant influences baseline levels of urinary 8-iso-PGF2α but not the aerobic exercise-induced responses.
OXIDATIVE STRESS; AEROBIC EXERCISE; CYBA GENE; NITRIC OXIDE; ISOPROSTANES
Yoga has been shown to be a simple and economical therapeutic modality that may be considered as a beneficial adjuvant for type 2 diabetes mellitus. This study investigated the impact of Hatha yoga and conventional physical training (PT) exercise regimens on biochemical, oxidative stress indicators and oxidant status in patients with type 2 diabetes.
This prospective randomized study consisted of 77 type 2 diabetic patients in the Hatha yoga exercise group that were matched with a similar number of type 2 diabetic patients in the conventional PT exercise and control groups. Biochemical parameters such as fasting blood glucose (FBG), serum total cholesterol (TC), triglycerides, low-density lipoprotein (LDL), very low-density lipoproteins (VLDL) and high-density lipoprotein (HDL) were determined at baseline and at two consecutive three monthly intervals. The oxidative stress indicators (malondialdehyde – MDA, protein oxidation – POX, phospholipase A2 – PLA2 activity) and oxidative status [superoxide dismutase (SOD) and catalase activities] were measured.
The concentrations of FBG in the Hatha yoga and conventional PT exercise groups after six months decreased by 29.48% and 27.43% respectively (P < 0.0001) and there was a significant reduction in serum TC in both groups (P < 0.0001). The concentrations of VLDL in the managed groups after six months differed significantly from baseline values (P = 0.036). Lipid peroxidation as indicated by MDA significantly decreased by 19.9% and 18.1% in the Hatha yoga and conventional PT exercise groups respectively (P < 0.0001); whilst the activity of SOD significantly increased by 24.08% and 20.18% respectively (P = 0.031). There was no significant difference in the baseline and 6 months activities of PLA2 and catalase after six months although the latter increased by 13.68% and 13.19% in the Hatha yoga and conventional PT exercise groups respectively (P = 0.144).
The study demonstrate the efficacy of Hatha yoga exercise on fasting blood glucose, lipid profile, oxidative stress markers and antioxidant status in patients with type 2 diabetes and suggest that Hatha yoga exercise and conventional PT exercise may have therapeutic preventative and protective effects on diabetes mellitus by decreasing oxidative stress and improving antioxidant status.
Australian New Zealand Clinical Trials Registry (ANZCTR): ACTRN12608000217303
While aerobic training and, to a lesser degree, resistance training are known to reduce blood concentrations of low-density lipoprotein cholesterol (LDL-C), little is known about the effects of a combination of aerobic and resistance training on LDL-C concentrations. The aim of the investigation was to examine the effects of 16 weeks of no exercise, aerobic training or a combination of aerobic and resistance training on lowering blood concentrations of LDL-C.
Thirty-eight healthy, previously untrained men (mean age: 25 years and six months) with borderline high blood LDL-C concentrations volunteered to participate in this investigation. Each subject’s blood LDL-C concentrations were measured following a nine- to 12-hour fasting period and prior to any exercise. Aerobic training consisted of exercise using a combination of treadmills, rowers, steppers and cycle ergometers. Combined aerobic and resistance training consisted of a combination of aerobic training at 60% of heart rate maximum, and resistance training using eight prescribed exercises performed for two sets of 15 repetitions at 60% of the estimated one-repetition maximum (1-RM).
The no-exercise group was found to have had no significant (p ≤ 0.05) change in blood LDL-C concentrations (from 4.12 ± 0.27 to 4.21 ± 0.42 mmol.l-1), whereas the aerobic training and combined training groups showed significant and similar (p = 0.123) decreases in blood LDL-C concentrations (from 3.64 ± 2.87 to 2.87 ± 0.64 mmol.l-1 and from 4.39 ± 1.04 to 3.23 ± 0.71 mmol.l-1, respectively). This investigation indicates that a larger dose of aerobic exercise does not necessarily equate to a greater improvement in LDL-C concentrations if the lost aerobic exercise time is replaced with resistance exercise.
Objective. The aim of the present study was to evaluate the oxidative stress biomarkers in patients with subclinical hypothyroidism (n = 20) and health controls (n = 20). Subjects and Methods. Total cholesterol (TC), triglycerides (TGs), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), thiobarbituric acid reactive substances (TBARSs), catalase (CAT), superoxide dismutase (SOD), and arylesterase (ARE) were analyzed. Results. TC, LDL-C, TBARS, and CAT were higher in subclinical hypothyroidism patients, whereas SOD did not change. Arylesterase activity was significantly lower in the SH group, compared with the control group. Correlation analyses revealed the association of lipids (TC and LDL-C) with both oxidative stress biomarkers and thyrotropin (TSH). Thyroid hormones were correlated only with triglyceride levels. In addition, TSH was significantly correlated with TBARS, CAT, and SOD. However, no significant correlations were observed after controlling TC levels. Conclusions. We found that SH patients are under increased oxidative stress manifested by reduced ARE activity and elevated lipoperoxidation and CAT activity. Secondary hypercholesterolemia to thyroid dysfunction and not hypothyroidism per se appears to be associated with oxidative stress in subclinical hypothyroidism.
There is a relationship among hypercholesterolemia, oxidative stress and inflammation in the atherogenesis. Thus, the objective of the present study was to assess paraoxonase (PON1), superoxide dismutase (SOD) and thioredoxin reductase (TrxR-1) activities and their relationship with lipids, oxidative stress and inflammation in subjects with different low density lipoprotein-cholesterol (LDL) levels.
Serum lipids, highly sensitive C-reactive protein (hs-CRP), lipid and protein oxidation, oxidized LDL (LDLox) and LDLox autoantibodies (LDLoxAB) levels and enzymes activities were measured in a total of 116 subjects that were divided into the following groups according to their LDL levels: low-LDL group (LDL < 100 mg/dL, n = 23), intermediate-LDL group (LDL 100–160 mg/dL, n = 50) and high-LDL group (LDL > 160 mg/dL, n = 43).
The LDLox and hs-CRP levels increased in the high-LDL group (2.7- and 3.7- fold, respectively), whereas the intermediate and high-LDL groups had higher LDLoxAB (2.2- and 3.1-fold) when compared to low-LDL group (p < 0.05). Similarly, SOD activity, the atherogenic index (AI) and protein oxidation were also higher in the intermediate (1.3-, 1.3- and 1.2-fold) and high-LDL (1.6-, 2.3- and 1.6-fold) groups when compared to the low-LDL group (p < 0.05). Lipid oxidation and SOD/TrxR-1 ratio increased only in the high-LDL group (1.3- and 1.6-fold) when compared to the low-LDL group (p < 0.05). The SOD/TrxR-1 ratio was positively correlated to TBARS (r = 0.23, p < 0.05), LDLox (r = 0.18, p < 0.05), LDLoxAB (r = 0.21, p < 0.05), LDL (r = 0.19, p < 0.05) and AI (r = 0.22, p < 0.05). PON1 and TrxR-1 activities were similar among groups.
Some oxidative events initiate when LDL levels are clinically acceptable. Moreover, hypercholesterolemic patients have an imbalance in SOD and TrxR-1 activities that is positively associated to LDL oxidation.
Atherogenic index; Hypercholesterolemia; Oxidized low density lipoprotein; Superoxide dismutase; Thioredoxin reductase
The present study was designed to evaluate the effects of aerobic and strength training on cardiac variables such as blood pressure, heart rate (HR), and metabolic parameters like cholesterol, high density lipoprotein (HDL), triglycerides and anthropometric parameters of obese women of Punjab.
This study was performed as an experimental study, in which subjects were randomly selected. There were thirty obese women, aged between 35-45yrs with body mass index (BMI) of above 30. Subjects were grouped into control (n=10), aerobic training (n=10) and resistance training (n=10). Aerobic training was given for three days a week at 60-70% of maximum HR for 6 weeks. Resistance training (Delorme and Watkins Technique) was given for alternate days for 6 weeks. HR and blood pressure were measured before and after the exercise. Recovery HR was also measured.
The findings of the study indicate statistically significant differences in recovery heart rate [Pre-exercise: 97.40± 5.378 (mean±standard deviation (SD)), post-exercise: 90.70±4.599, t=8.066, P<0.001] and in post-diastolic blood pressure [Pre-exercise: 85±3.265, post-exercise: 86.20±2.820, P<0.001] in aerobic training and in systolic blood pressure [Pre- and post-exercise] in both training groups (P<0.001). Significant differences were observed in very low-density lipoprotein [pre-exercise: 28.10±1.415, post-exercise: 26.86±0.760, t=5.378] and HDL [pre-exercise: 45.40±3.533, post-exercise: 53.60±3.134, t=6.318] levels in aerobic training group with P<0.001. BMI and body fat percentage showed significant improvements in both training groups.
Aerobic training is more beneficial and can be used as a preventive measure in patients who are at risk of developing cardiovascular diseases due to obesity.
Aerobic exercise; Resistance training; Obesity; Heart rate; Physical fitness
We aimed to investigate the effects of creatine (Cr) supplementation on the plasma lipid profile in sedentary male subjects undergoing aerobic training.
Subjects (n = 22) were randomly divided into two groups and were allocated to receive treatment with either creatine monohydrate (CR) (~20 g·day-1 for one week followed by ~10 g·day-1 for a further eleven weeks) or placebo (PL) (dextrose) in a double blind fashion. All subjects undertook moderate intensity aerobic training during three 40-minute sessions per week, over 3 months. High-density lipoprotein cholesterol (HDL), low-density lipoprotein cholesterol (LDL), very low-density lipoprotein cholesterol (VLDL), total cholesterol (TC), triglyceride (TAG), fasting insulin and fasting glycemia were analyzed in plasma. Thereafter, the homeostasis model assessment (HOMA) was calculated. Tests were performed at baseline (Pre) and after four (Post 4), eight (Post 8) and twelve (Post 12) weeks.
We observed main time effects in both groups for HDL (Post 4 versus Post 8; P = 0.01), TAG and VLDL (Pre versus Post 4 and Post 8; P = 0.02 and P = 0.01, respectively). However, no between group differences were noted in HDL, LDL, CT, VLDL and TAG. Additionally, fasting insulin, fasting glycemia and HOMA did not change significantly.
These findings suggest that Cr supplementation does not exert any additional effect on the improvement in the plasma lipid profile than aerobic training alone.
Fenofibrate significantly reduces circulating triglyceride (TG) concentrations, particularly in individuals with elevated levels. The purpose of the current study was to determine whether fenofibrate treatment reduces markers of oxidative stress, oxidized low density lipoprotein (ox-LDL) and 8-isoprostane (8-isoP), in a manner similar to TG where those with the highest levels show the greatest reductions.
The concentrations of TG, 8-isoP, and ox-LDL were measured in plasma before and after 3 weeks of fenofibrate treatment (160 mg/d) in a sub-cohort (n=187) of the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) study.
Data were divided into tertiles as determined by pre-treatment values of the respective target. Fenofibrate treatment resulted in significant reductions in TG concentrations by 24.2% (p<0.0001), 41.9% (p<0.0001), and 46.6% (p<0.0001) in tertiles 1, 2, and 3, respectively. Significant reductions were also observed in ox-LDL of 7.2% (p=0.0096), 8.5% (p=0.0019) and 12.1% (p<0.0001) in tertiles 1, 2, and 3, respectively. Finally, fenofibrate treatment resulted in a 32.7% increase (p=0.0201) in 8-isoP levels in tertile 1, but a significant decrease of 34.4% (p<0.0001) in tertile 3.
This study is the largest to date to demonstrate that fenofibrate reduces oxidative stress and the first to show a suppressive effect on 8-isoP levels in individuals with a high oxidative burden following short term (3 wk) drug therapy. Those with the highest baseline levels of ox-LDL and 8-isoP showed the greatest reductions following fenofibrate treatment. Given the role of oxidative stress in atherosclerosis and coronary heart disease, our observations may partially explain the efficacy of fenofibrate in reducing cardiovascular events in select patients.
Fenofibrate; atherosclerosis; isoprostane; ox-LDL; triglyceride; GOLDN
The mechanisms of the changes in plasma lipids concentrations observed after beta-blockade were examined in 53 patients with hypertension receiving treatment with atenolol, metoprolol, propranolol, and oxprenolol in a randomised cross-over trial. Significant increases in mean plasma total and very-low-density lipoprotein (VLDL) triglyceride and reductions in high-density lipoprotein (HDL) cholesterol and free fatty acids concentrations wer observed with all four drugs, the increase in plasma triglyceride concentration being greatest after propranolol and oxprenolol. No significant changes were observed in total of LDL cholesterol concentrations, but HDL:LDL ratios and HDL cholesterol as a proportion of total cholesterol fell significantly. Thus plasma lipid concentrations should be monitored after three to six months of long-term treatment. Changes in triglyceride, HDL cholesterol and free fatty acid concentrations were associated with a highly significant reduction in clearance of soya oil (Intralipid) in 25 patients studied but were unrelated to changes in blood pressure. The fall in HDL cholesterol and rise in free fatty acid concentrations were significantly less in those with initially reduced HDL cholesterol or raised free fatty acid concentrations respectively. It is proposed that unopposed alpha stimulation inhibits lipoprotein lipase with a subsequent rise in plasma triglyceride and fall in HDL cholesterol concentration. Analysis of the relation between pretreatment concentrations and subsequent changes suggests that excessive alpha stimulation may impair production of HDL cholesterol in those with low HDL cholesterol concentrations before treatment. Subtle catecholamine-mediated changes in plasma lipid concentrations might provide a mechanism for the relation between stress and the development of cardiovascular events.
The metabolism of hypertriglyceridemic low density lipoprotein (HTG-LDL) was investigated in upregulated cultured human skin fibroblasts. Low density lipoprotein (LDL) was isolated by zonal centrifugation from the plasma of seven HTG subjects, before and 2 wk after the initiation of bezafibrate (BZ) therapy. HTG-LDL is a cholesterol-poor, triglyceride-rich lipoprotein of smaller diameter than BZ-LDL or normal LDL (N-LDL). Binding, cell association, and proteolytic degradation of HTG-LDL were compared with that of BZ-LDL and N-LDL and were found to be significantly lower by a paired t test analysis (P less than 0.001). After 6 h preincubation with unlabeled HTG-LDL, the incorporation of [14C]acetate to sterols was significantly higher than with BZ-LDL or N-LDL (577 +/- 43.7; 330 +/- 41.5; 262 +/- 47, mean +/- SE, picomoles sterols per milligram cell protein per 2 h, respectively; P less than 0.001 by paired t test). To determine the effectiveness of HTG-LDL and BZ-LDL on the down-regulation of LDL receptor activity, up-regulated cells were incubated for 48 h with HTG-LDL and BZ-LDL. LDL receptor activity was significantly higher after preincubation with HTG-LDL compared with BZ-LDL, and the rates of sterol synthesis were similarly increased. These results demonstrate that HTG-LDL does not down-regulate the LDL receptor activity as efficiently as BZ-LDL and that its cholesterol content is not enough to adequately suppress cellular sterol synthesis. Significant correlation between LDL composition and cholesterol synthesis by cultured cells was found with all LDL preparations over a wide range of cholesteryl ester to protein ratio (0.8-2.2). This correlation indicates that the compositional and structural abnormalities of HTG-LDL, and especially the low cholesterol content of the lipoprotein, alter LDL metabolism and cellular cholesterol formation.
Use the meta-analytic approach to examine the effects of aerobic exercise on lipids and lipoproteins in adults with cardiovascular disease (CVD).
Studies were retrieved via electronic databases, review of reference lists from retrieved articles, including reviews, and hand searching. Inclusion criteria were: (1) randomized controlled trials, (2) aerobic exercise ≥4 weeks as an intervention, (3) studies published in English language only between January 1, 1955 and January 1, 2005, (4) studies published in journals or as dissertations or master's theses, (5) human subjects ≥18 years, (6) all subjects diagnosed with some type of CVD, and (7) pre and post data available for total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and/or triglycerides (TG). Random-effects models were used for data analysis.
Of the more than 3,000 studies reviewed, a total of 10 representing 1,260 subjects (580 exercise, 680 control) were included in our analysis. There was a statistically significant increase of 9% in HDL-C (mean ± SEM, 3.7 ± 1.3 mg/dL; 95% CI, 1.2 to 6.1 mg/dL) and a statistically significant decrease of 11% in TG (−19.3 ± 5.4 mg/dL; 95% CI, −30.1 to −8.5 mg/dL), but no statistically significant decreases in TC or LDL-C (TC, −8.8 ± 6.8 mg/dL; 95% CI, −22.3 to 4.7 mg/dL; LDL-C, −7.7 ± 6.0 mg/dL; 95% CI, −19.5 to 4.2 mg/dL).
The present findings suggest that chronic aerobic exercise increases HDL-C and decreases TG in adults, especially men, with CVD.
aerobic; cardiovascular disease; exercise; lipids; meta-analysis
The effects of beta adrenoceptor blockade with propranolol or pindolol on serum total cholesterol, low density lipoprotein cholesterol (LDL), high density lipoprotein cholesterol (HDL), and its subfractions HDL2 and HDL3, serum triglyceride, and Intralipid clearance were studied in 17 normolipidaemic, non-diabetic patients with hypertension or angina pectoris. Both pindolol and propranolol had similar effects on fasting serum total and lipoprotein cholesterol concentrations. HDL2 cholesterol concentrations were reduced by 9 +/- 29% and HDL3 cholesterol increased by 11 +/- 16%, but there were no significant changes in total or LDL cholesterol in the combined groups after six weeks' treatment. After 12 weeks' treatment total cholesterol concentrations were reduced by 7 +/- 10% mainly owing to a reduction in the LDL fraction of 9 +/- 15%. Concentrations of HDL2 remained low, 8% less than control values. Serum triglyceride concentrations were increased by both drugs at six weeks but had returned to base values in the pindolol group by the twelfth week. Pindolol, but not propranolol, enhanced the rate of clearance of intravenous Intralipid.
Cigarette smoke-induced oxidative stress leads to dyslipidemia and systemic inflammation. Morinda citrifolia (noni) fruit juice has been found previously to
have a significant antioxidant activity. One hundred thirty-two adult heavy smokers completed a randomized, double blind, placebo-controlled clinical trial designed to investigate the effect of noni juice on serum cholesterol, triglyceride, low density lipoprotein cholesterol (LDL), high density lipoprotein cholesterol (HDL), high-sensitivity C-reactive protein (hs-CRP), and homocysteine. Volunteers drank noni juice or a fruit juice placebo daily for one month. Drinking 29.5 mL to 188 mL of noni juice per day significantly reduced cholesterol levels, triglycerides, and hs-CRP. Decreases in LDL and homocysteine, as well increases in HDL, were also observed among noni juice drinkers. The placebo, which was devoid of iridoid glycosides, did not significantly influence blood lipid profiles or hs-CRP. Noni juice was able to mitigate cigarette smoke-induced dyslipidemia, an activity associated with the presence of iridoids.
Use the meta-analytic approach to examine the effects of aerobic exercise on total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG) in children and adolescents.
Randomized controlled trials which were limited to aerobic exercise ≥4 weeks in children and adolescents 5–19 years of age.
Twelve outcomes representing 389 subjects were available for pooling. Using random-effects modeling, a trend for statistically significant decreases of 12% was found for TG (X̄ ± S.E.M., −11.0 ± 6.1 mg/dl; 95% CI, −22.8–0.8 mg/dl) with no statistically significant changes for TC, HDL-C, and LDL-C. Decreases in LDL-C were associated with increased training intensity (r = −0.89; 99% CI, −0.99 to −0.04) and older age (r = −0.90; 99% CI, −0.99 to −0.25) while increases in HDL-C were associated with lower initial HDL-C (r = −0.75; 99% CI, −0.94 to −0.80). Statistically significant decreases in TG were observed in overweight/obese subjects with a trend for increases in HDL-C (TG, X̄ ± S.E.M., −23.9 ± 7.0 mg/dl; 95% CI, −37.6 to −10.1 mg/dl; HDL-C, X̄ ± S.E.M., 4.0 ± 2.3 mg/dl; 95% CI, −0.5–8.5 mg/dl).
Aerobic exercise decreases TG in overweight/obese children and adolescents.
Children; Adolescents; Exercise; Cholesterol; Lipids; Meta-analysis; Systematic review
The growing evidences demonstrated hyperlipidemia in obesity and type 2 diabetes is characterized by high levels of free fatty acids, low-density lipoprotein (LDL), triglyceride, and cholesterol.
Method and Results
We investigated the effect of LDL particles (LDLs) loading on MIN6 cells derived from pancreatic β cells. Exposure of MIN6 cells to LDLs induced apoptosis in dose and time-dependent manner, demonstrated by the TUNEL in situ apoptotic assay. The immunocytochemical analysis and Western blotting revealed that the LDLs-induced apoptosis is associated with the activation of caspase 3 and upregulation of p53. The intracellular concentration of Reactive Oxygen Species (ROS) measured by use of DCFHDA was significantly increased after loading LDLs, demonstrating the induced apoptosis by LDLs loading was mediated through oxidative stress. Addition of reduced form of Glutathione (GSH) in the medium rescued MIN6 cells from apoptosis. The Cellular cholesterol level was increased significantly after LDLs loading, suggesting that the excess cholesterol induced by LDLs loading might contribute to the apoptosis in MIN6s. Agarose electrophoresis demonstrated that the LDLs added to the medium were not oxidized.
Taken together, these results demonstrate that the LDLs loading can induce apoptosis of MIN6 cells mediated by the excess cellular cholesterol and generation of oxidative stress.
LDLS; MIN6; apoptosis; ROS
Thymoquinone (TQ), derived from Nigella sativa seed, is an antioxidant. The present study investigated whether TQ attenuates the development of atherosclerosis, and/or reduces the serum lipid levels and oxidative stress in rabbits. New Zealand white female rabbits were assigned to four groups of six animals each: group I, control; group II, 1% cholesterol diet; group III, 1% cholesterol plus TQ (10 mg/kg/day; through a nasogastric tube) diet; and group IV, 1% cholesterol plus TQ (20 mg/kg/day; through a nasogastric tube) diet. Blood samples were collected at baseline and after four and eight weeks on the experimental diets for measurement of serum lipids, total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), TC/HDL-C ratio and oxidative stress biomarkers (malondialdehyde [MDA] and protein carbonyls). At the end of the eight weeks, the aorta was removed for the assessment of atherosclerotic changes, MDA and protein carbonyls. Group II animals developed atherosclerosis (45%±11% of the intimal surface of aorta was covered with atherosclerotic plaques), which was associated with an increase in the serum TC, TG, LDL-C, HDL-C, TC/HDL-C, MDA and protein carbonyls. In group III, TQ decreased serum TC, LDL-C, MDA and protein carbonyls by 26%, 29%, 85% and 62%, respectively, and aortic MDA by 73%, which was associated with a 40% reduction of the development of aortic atherosclerosis. The higher dose of TQ in group IV had effects similar to the lower dose (group III), except that this dose further decreased serum TG. It is concluded that TQ attenuates hypercholesterolemic atherosclerosis and this effect is associated with a decrease in serum lipids and oxidative stress.
Atherosclerosis; Hypercholesterolemia; Reactive oxygen species; Thymoquinone
Oxidative stress has been demonstrated in malaria. The potential oxidative modification of lipoproteins derived from malaria patients was studied. These oxidized lipids may have role in pathogenesis of malaria.
The plasma lipid profile and existence of oxidized forms of very low density lipoprotein (VLDL), low density lipoprotein (LDL) and high density lipoprotein (HDL) were investigated in malaria (17 mild and 24 severe patients) and 37 control subjects. Thiobarbituric acid reactive substances (TBARs), conjugated dienes, tryptophan fluorescence and fluidity of lipoproteins were determined as markers of oxidation. The biological effect of malarial lipoproteins was assessed by the expression of adhesion molecules on endothelial cells.
Malarial lipoproteins had decreased cholesterol (except in VLDL) and phospholipid. The triglyceride levels were unchanged. The cholesterol/phospholipid ratio of LDL was decreased in malaria, but increased in VLDL and HDL. TBARs and conjugate dienes were increased in malarial lipoproteins, while the tryptophan fluorescence was decreased. The fluidity of lipoproteins was increased in malaria. These indicated the presence of oxidized lipoproteins in malaria by which the degree of oxidation was correlated with severity. Of three lipoproteins from malarial patients, LDL displayed the most pronounced oxidative modification. In addition, oxidized LDL from malaria patients increased endothelial expression of adhesion molecules.
In malaria, the lipoproteins are oxidatively modified, and the degree of oxidation is related with severity. Oxidized LDL from malarial patients increases the endothelial expression of adhesion molecules. These suggest the role of oxidized lipoproteins, especially LDL, on the pathogenesis of disease.
malaria; oxidative stress; lipid profile; lipoprotein; oxidized LDL; endothelial cell; adhesion molecules
The following review aims to describe what is known about the effects of exercise training in children and adolescents on the following blood lipids and lipoproteins: total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), and triglycerides (TG). Only studies that described mode, frequency, duration and intensity of the exercise were included in the review. The results of the studies reviewed were equivocal. Clearly the effects of exercise training on the blood lipid and lipoprotein levels of normolipidemic children and adolescents are equivocal. Of the 14 studies reviewed, six observed a positive alteration in the blood lipid and lipoprotein profile, four of the studies observed no alteration in the blood lipid and lipoprotein profile and one study observed a negative effect on HDL-C but an overall improvement in the lipid and lipoprotein profile due to the decrease in the TC/HDL ratio. It appears that methodological problems present in the majority of the exercise training studies limits the ability to make a conclusive, evidence based statement regarding the effect exercise training has on blood lipid levels in normolipidemic children. Most of the research design flaws can be linked to one or more of the following: small numbers of subjects in each study, low or no representation of girls, inclusion of both boys and girls in the subject pool, inclusion of boys and girls at different maturational stages in the subject pool, exercise training regimes that do not adequately control for exercise intensity, exercise training regimes that do not last longer than 8 weeks and exercise training studies that do not have an adequate exercise volume to elicit a change. Ideally, future research should focus on longitudinal studies which examine the effects of exercise training from the primary school years through adulthood.
Exercise training has limited to no effect on blood lipid levels in children and adolescents.
Few well controlled studies have been done to examine the effect exercise training has on selected cardiovascular risk factors and those studies that have been completed contain methodological flaws which makes interpretation of the results difficult.
More studies, particularly those of a longitudinal design, are required before a conclusion can be drawn regarding the effects exercise training has on selected cardiovascular risk factors in children and adolescents.
Cardiovascular risk factors; children; adolescents; aerobic exercise training
Dyslipidemia has been established as a well-known traditional risk factor for cardiovascular disease in chronic kidney disease patients.
This study investigated the impact of Hatha yoga exercise on lipid parameters in patients with end-stage renal disease (ESRD) on hemodialysis.
Materials and Methods:
This prospective randomized study consisted of 33 ESRD patients in the Hatha yoga exercise group that was matched with 35 ESRD patients in the control group. Serum total cholesterol, triglycerides, low-density lipoprotein (LDL)-cholesterol, and high-density lipoprotein (HDL)-cholesterol were determined at baseline (0 month) and after 4 months.
Comparing values after 4 months versus baseline in the prehemodialysis Hatha yoga exercise group, there was found a significant decrease in total cholesterol from 5.126 ± 0.092 mmol/l to 4.891 ± 0.072 mmol/l (-4.58%; P = 0.0001), triglycerides from 2.699 ± 0.078 mmol/l to 2.530 ± 0.063 mmol/l (-6.26%; P = 0.0001), LDL-cholesterol from 2.729 ± 0.083 mmol/l to 2.420 ± 0.066 mmol/l (-11.32%; P = 0.0001), and total cholesterol/HDL-cholesterol ratio from 5.593 ± 0.119 mmol/l to 4.907 ± 0.116 mmol/l (-12.26%; P = 0.047). For patients in the Hatha yoga exercise group, 51.5% had normal total cholesterol at 0 month while 70.0% had normal total cholesterol (P < 0.05) after 4 four months and 54.5% of patients had normal LDL-cholesterol at 0 month while 84.9% had normal LDL-cholesterol after 4 months (P < 0.05).
These findings suggest that Hatha yoga exercise has preventive and beneficial effects and may be a safe therapeutic modality in ESRD patients.
Cardiovascular; end-stage renal disease; hatha yoga exercise; total cholesterol
Studies were designed to explore the association of lipoprotein lipase (LPL) and hepatic triglyceride lipase (HTGL) activities with lipoproteins in human postheparin plasma (PHP). The major peak of LPL activity after gel filtration of PHP eluted after the triglyceride-rich lipoproteins and just before the peak of low density lipoprotein (LDL) cholesterol. When PHP contained chylomicrons, an additional peak of LPL activity eluted in the void volume of the column. Most HTGL activity eluted after the LDL and preceded the elution of high density lipoprotein cholesterol. LPL activity in preheparin plasma eluted in the same position, relative to lipoproteins, as did LPL in PHP. Gel filtration of purified human milk LPL mixed with plasma or isolated LDL produced a peak of activity eluting before LDL. During gel filtration of PHP in high salt buffer (1 M NaCl) or after isolation of lipoproteins by ultracentrifugation in high salt density solutions, most of the lipase activity was not associated with lipoproteins. LPL activity was removed from PHP by elution through immunoaffinity columns containing antibodies to apolipoprotein (apo) B and apo E. Since lipoproteins in PHP have undergone prior in vivo lipolysis, LPL activity in PHP may be bound to remnants of chylomicrons and very low density lipoproteins.
The purpose of this study was to determine independent relationships of intra-abdominal adipose tissue (IAAT), leg fat, and aerobic fitness with blood lipids and insulin sensitivity (Si) in European-American (EA) and African-American (AA) premenopausal women. Ninety-three EA and ninety-four AA with BMI between 27 and 30 kg/m2 had IAAT by computed tomography, total fat and leg fat by dual-energy X-ray absorptiometry, aerobic fitness by a graded exercise test, African admixture (AFADM) by ancestry informative markers, blood lipids by the Ektachem DT system, and Si by glucose tolerance test. Independent of age, aerobic fitness, AFADM, and leg fat, IAAT was positively related to low-density lipoprotein–cholesterol (LDL-C), cholesterol-high-density lipoprotein (HDL) ratio, triglycerides (TGs), and fasting insulin (standardized β varying 0.16–0.34) and negatively related to HDL-cholesterol (HDL-C) and Si (standardized β −0.15 and −0.25, respectively). In contrast, independent of age, aerobic fitness, AFADM, and IAAT, leg fat was negatively related to total cholesterol, LDL-C, cholesterol-HDL ratio, TGs, and fasting insulin (standardized β varying −0.15 to −0.21) and positively related to HDL-C and Si (standardized β 0.16 and 0.23). Age was not independently related to worsening of any blood lipid but was related to increased Si (standardized β for Si 0.25, insulin −0.31). With the exception of total cholesterol and LDL-C, aerobic fitness was independently related to worsened blood lipid profile and increased Si (standardized β varying 0.17 to −0.21). Maintenance of favorable fat distribution and aerobic fitness may be important strategies for healthy aging, at least in premenopausal EA and AA women.
Physical exercise protects against the development of cardiovascular disease, partly by lowering plasmatic total cholesterol, LDL-cholesterol and increased HDL-cholesterol levels. In addition, it is now established that reduction plasmatic adiponectin and increased C-reactive protein (CRP) and plasminogen activator inhibitor-1 (PAI-1) levels play a role in the maintenance of an inflammatory state and in the development of cardiovascular disease. This study aimed to examine plasma lipid profile and inflammatory markers levels in individual with sedentary lifestyle and/or highly trained athletes at rest. Methods: Fourteen male subjects (sedentary lifestyle n = 7 and highly trained athletes n = 7) were recruited. Blood samples were collected after an overnight fast (~12 h). The plasmatic lipid profile (Triglycerides, HDL-cholesterol, LDL-cholesterol, total cholesterol, LDL-oxidized and total cholesterol/HDL-c ratio), glucose, adiponectin, C - reactive protein and PAI-1 levels were determined. Results: Total cholesterol, LDL-cholesterol, TG and PAI-1 levels were lower in highly trained athletes group in relation to sedentary subjects (p < 0.01). In addition, we observed a positive correlation between PAI-1 and total cholesterol (r = 0.78; p < 0.0009), PAI-1 and LDL-c (r = 0.69; p < 0.006) and PAI-1 and TG levels (r = 0.56; p < 0.03). The plasma concentration of adiponectin, CRP, glucose, HDL-cholesterol and total cholesterol/HDL-c ratio levels were not different. These results indicate that lifestyle associated with high intensity and high volume exercise induces changes favourable in the lipid profile and PAI-1 levels and may reduce risk cardiovascular diseases.