Effects of High-Intensity Interval Training on Melatonin Function and Cellular Lymphocyte Apoptosis in Sedentary Middle-Aged Men

Background: Physical performance increased by controlled interventions of high-intensity intermittent training (HIIT); however, little is known about their influence as anti-aging and antioxidant effects, or their role in mitochondrial biogenesis. Purpose: This study aimed to determine the effects of HIIT for 12 weeks on melatonin function, lymphocyte cell apoptosis, oxidative stress on aging, and physical performance. Methods: Eighty healthy male subjects aged 18-65 years randomly participated in a HIIT-exercise training program for 12 weeks. Anthropometric analysis, cardiovascular fitness, total antioxidant capacity (TAC), lymphocyte count and apoptosis, and serum melatonin and cytochrome c oxidase (COX), were estimated for all subjects before and after HIIT-exercise training. HIIT training was performed in subjects for 12 weeks. Results: Data analysis showed a significant increase in the expression levels of the melatonin hormone (11.2 ± 2.3, p < 0.001), TAC (48.7 ± 7.1, p < 0.002), COX (3.7 ± 0.75, p < 0.001), and a higher percentage of lymphocyte apoptosis (5.2 ± 0.31, p < 0.003). In addition, there was an improvement in fitness scores (W; 196.5 ± 4.6, VO₂max; 58.9 ± 2.5, p < 0.001), adiposity markers (p < 0.001); BMI, WHtR, and glycemic control parameters (p < 0.01); FG, HbA1c (%), FI, and serum C-peptide were significantly improved following HIIT intervention. Both melatonin and lymphocyte apoptosis significantly correlated with the studied parameters, especially TAC and COX. Furthermore, the correlation of lymphocyte apoptosis with longer exercise duration was significantly associated with increased serum melatonin following exercise training. This association supports the mechanistic role of melatonin in promoting lymphocyte apoptosis either via the extrinsic mediator pathway or via inhibition of lymphocyte division in the thymus and lymph nodes. Additionally, the correlation between melatonin, lymphocyte apoptosis, TAC, and COX activities significantly supports their role in enhancing physical performance. Conclusions: The main findings of this study were that HIIT exercise training for 12 weeks significantly improved adiposity markers, glycemic control parameters, and physical performance of sedentary older adult men. In addition, melatonin secretion, % of lymphocyte apoptosis, COX activities, and TAC as biological aging markers were significantly increased following HIIT exercise training interventions for 12 weeks. The use of HIIT exercise was effective in improving biological aging, which is adequate for supporting chronological age, especially regarding aging problems. However, subsequent studies are required with long-term follow-up to consider HIIT as a modulator for several cardiometabolic health problems in older individuals with obesity.

Association between adiponectin and newly diagnosed type 2 diabetes in population with the clustering of obesity, dyslipidaemia and hypertension: a cross-sectional study

OBJECTIVES

Adiponectin is closely related to glucose metabolism and traditional diabetes risk factors (obesity, hypertension and dyslipidaemia). We aimed to explore the association between adiponectin levels and newly diagnosed type 2 diabetes mellitus (T2DM) and pre-diabetes in subgroups classified according to T2DM risk factors.

SETTING

Sun Yat-sen Memorial Hospital of Sun Yat-sen University.

PARTICIPANTS

3680 individuals (1753 men and 1927 women) aged 18-70 years from Guangzhou and Dongguan, China, were enrolled from December 2018 to October 2019.

PRIMARY AND SECONDARY OUTCOME MEASURES

T2DM was defined as fasting plasma glucose (FPG)≥7.0 mmol/L or HbA1c≥6.5%, and pre-diabetes was defined as 6.1 mmol/L≤FPG<7.0 mmol/L or 5.7≤HbA1c<6.5%.

RESULTS

With the increasing number of T2DM risk factors, the proportion of the population with high-quartile adiponectin levels gradually decreased (p<0.001). A low level of adiponectin was significantly associated with diabetes and pre-diabetes in a population with ≥1 T2DM risk factor, whereas its association was not consistently significant in the population with all three T2DM risk factors. For instance, participants were more likely to have diabetes or prediabetes with low levels of adiponectin when they had ≥ one T2DM risk factor (quartile 2 vs. 1: OR 0.71 [95%CI: 0.56-0.89]; P=0.003; quartile 3 vs. 1: OR 0.57 [95%CIs: 0.44-0.72]; P<0.001; and quartile 4 vs. 1: OR 0.52 [95%CIs: 0.40-0.67]; P<0.001).

CONCLUSION

Adiponectin was negatively associated with diabetes and pre-diabetes in a population with few T2DM risk factors, while their relationship gradually attenuated with the accumulation of T2DM risk factors, especially in a population with coexisting diseases such as obesity, hypertension and dyslipidaemia.

Aerobic physical training impact on adipokines in women with polycystic ovary syndrome - Effects of body fat percentage

Objective

We investigated the effects of aerobic training on adipokine concentrations in women with polycystic ovary syndrome (PCOS).

Subjects and methods

120 women, including 60 with PCOS and 60 without PCOS, were divided into six groups (n = 20) based on body fat percentages of 22%-27%, 28%-32%, and 33%-37%. All groups were submitted the same evaluations before and after 16 weeks of aerobic training. These included anthropometric and hemodynamic analyses, cardiopulmonary tests, and laboratory tests. Two-way analysis of variance was performed to evaluate the differences between women with and without PCOS, effect of the body fat percentage, and effect of aerobic training.

Results

Body fat and PCOS were associated with high values of blood glucose, insulin, and testosterone. Body fat also reduced adiponectin levels and increased leptin, tumor necrosis factoralpha (TNF-α), and interleukin-6 (IL-6). In contrast, the PCOS increased only TNF-α and IL-6 levels. In the PCOS group, aerobic training reduced insulin, triglycerides, leptin, and IL-6 levels. It also promoted an increase in adiponectin and high-density lipoprotein levels. However, aerobic training did not alter TNF-α concentrations.

Conclusion

The body fat potentiates metabolic impairments that may be harmful to women with PCOS. Aerobic training appears to promote an important beneficial effect on the metabolic regulation of adipokines, except TNF-α.

Atherogenic Lipoproteins for the Statin Residual Cardiovascular Disease Risk

Randomized controlled trials (RCTs) show that decreases in low-density lipoprotein cholesterol (LDL-C) by the use of statins cause a significant reduction in the development of cardiovascular disease (CVD). However, one of our previous studies showed that, among eight RCTs that investigated the effect of statins vs. a placebo on CVD development, 56–79% of patients had residual CVD risk after the trials. In three RCTs that investigated the effect of a high dose vs. a usual dose of statins on CVD development, 78–87% of patients in the high-dose statin arms still had residual CVD risk. The risk of CVD development remains even when statins are used to strongly reduce LDL-C, and this type of risk is now regarded as statin residual CVD risk. Our study shows that elevated triglyceride (TG) levels, reduced high-density lipoprotein cholesterol (HDL-C), and the existence of obesity/insulin resistance and diabetes may be important metabolic factors that determine statin residual CVD risk. Here, we discuss atherogenic lipoproteins that were not investigated in such RCTs, such as lipoprotein (a) (Lp(a)), remnant lipoproteins, malondialdehyde-modified LDL (MDA-LDL), and small-dense LDL (Sd-LDL). Lp(a) is under strong genetic control by apolipoprotein (a), which is an LPA gene locus. Variations in the LPA gene account for 91% of the variability in the plasma concentration of Lp(a). A meta-analysis showed that genetic variations at the LPA locus are associated with CVD events during statin therapy, independent of the extent of LDL lowering, providing support for exploring strategies targeting circulating concentrations of Lp(a) to reduce CVD events in patients receiving statins. Remnant lipoproteins and small-dense LDL are highly associated with high TG levels, low HDL-C, and obesity/insulin resistance. MDA-LDL is a representative form of oxidized LDL and plays important roles in the formation and development of the primary lesions of atherosclerosis. MDA-LDL levels were higher in CVD patients and diabetic patients than in the control subjects. Furthermore, we demonstrated the atherogenic properties of such lipoproteins and their association with CVD as well as therapeutic approaches.

Exercise-Induced Browning of White Adipose Tissue and Improving Skeletal Muscle Insulin Sensitivity in Obese/Non-obese Growing Mice: Do Not Neglect Exosomal miR-27a

Exercise is considered as a favorable measure to prevent and treat childhood obesity. However, the underlying mechanisms of exercise-induced beneficial effects and the difference between obese and non-obese individuals are largely unclear. Recently, miR-27a is recognized as a central upstream regulator of proliferator-activated receptor γ (PPAR-γ) in contributing to various physiological and pathological processes. This study aims to explore the possible cause of exercise affecting white adipose tissue (WAT) browning and reversing skeletal muscle insulin resistance in obese/non-obese immature bodies. For simulating the process of childhood obesity, juvenile mice were fed with a basal diet or high-fat diet (HFD) and took 1 or 2 h swimming exercise simultaneously for 10 weeks. The obese animal model was induced by the HFD. We found that exercise hindered HFD-induced body fat development in growing mice. Exercise modified glucolipid metabolism parameters differently in the obese/non-obese groups, and the changes of the 2 h exercise mice were not consistent with the 1 h exercise mice. The level of serum exosomal miR-27a in the non-exercise obese group was increased obviously, which was reduced in the exercise obese groups. Results from bioinformatics analysis and dual-luciferase reporter assay showed that miR-27a targeted PPAR-γ. Exercise stimulated WAT browning; however, the response of obese WAT lagged behind normal WAT. In the HFD-fed mice, 2 h exercise activated the IRS-1/Akt/GLUT-4 signaling pathway in the skeletal muscles. In summary, our findings confirmed that exercise-induced beneficial effects are associated with exercise duration, and the response of obese and non-obese bodies is different. Exosomal miR-27a might be a crucial node for the process of exercise-induced browning of WAT and improving skeletal muscle insulin sensitivity.

Predictors of the Prevalence of Dyslipidemia and Influencing Factors for Young Health Examination Cohort: A Cross-Sectional Survey

Objectives: The objective of this study was to estimate the prevalence of dyslipidemia and associated influencing factors in young adults in the southeastern coastal area of China. Methods: This study adopted a cross-sectional survey and included 7,859 young people who underwent examinations at three hospitals in Wenzhou, Zhejiang Province, China. All subjects completed a questionnaire in the form of face-to-face interviews and underwent anthropometric measurements and biochemical tests. The continuous data are presented as the means ± standard deviations and were compared using Student's t-tests. The categorical variables are presented as proportions. The influencing factors associated with dyslipidemia were evaluated through a multivariate logistic regression. Results: The prevalence of dyslipidemia among young adults aged 18-45 years in the southeastern coast of China was high with 7.1, 15.0, 22.9, and 4.0% for high-total cholesterol (TC), high-triglyceride (TG), low-high-density lipoprotein cholesterol (HDL-C), and high-low-density lipoprotein cholesterol (LDL-C). Among those with dyslipidemia, a statistically significant difference in sex was observed, and all types of dyslipidemia were associated with smoking and alcohol consumption. However, those with high-TG, high-LDL, and low-HDL levels did not significantly differ in education level or occupation. The presence of dyslipidemia was significantly associated with increased age, the male sex (OR: 1.85, 95% CI: 1.39-2.21), smoking (OR: 2.02, 95% CI: 1.98-2.13), alcohol consumption (OR: 1.33, 95% CI: 1.16-1.63), overweight or obesity (OR: 2.01, 95% CI: 1.79-2.41), and intellectual work (OR: 1.36, 95% CI: 1.11-1.72). Conclusion: The prevalence of dyslipidemia among young adults aged 18-45 years in the southeastern coast of China was high. To prevent dyslipidemia at an early age, it is essential to conduct effective intervention programs targeting risk factors and to implement routine screening programs.

The effects of exercise training on lipid metabolism and coronary heart disease

Blood lipoproteins are formed by various amounts of cholesterol (C), triglycerides (TGs), phospholipids, and apolipoproteins (Apos). ApoA1 is the major structural protein of high-density lipoprotein (HDL), accounting for ~70% of HDL protein, and mediates many of the antiatherogenic functions of HDL. Conversely, ApoB is the predominant low-density lipoprotein (LDL) Apo and is an indicator of circulating LDL, associated with higher coronary heart disease (CHD) risk. Thus, the ratio of ApoB to ApoA1 (ApoB/ApoA1) is used as a surrogate marker of the risk of CHD related to lipoproteins. Elevated or abnormal levels of lipids and/or lipoproteins in the blood are a significant CHD risk factor, and several studies support the idea that aerobic exercise decreases CHD risk by partially lowering serum TG and LDL-cholesterol (LDL-C) levels and increasing HDL-C levels. Exercise also exerts an effect on HDL-C maturation and composition and on reverse C transport from peripheral cells to the liver to favor its catabolism and excretion. This process prevents atherosclerosis, and several studies showed that exercise training increases heart lipid metabolism and protects against cardiovascular disease. In these and other ways, it more and more appears that regular exercise, nutrition, and strategies to modulate lipid profile should be viewed as an integrated whole. The purpose of this review is to assess the effects of endurance training on the nontraditional lipid biomarkers, including ApoB, ApoA1, and ApoB/ApoA1, in CHD risk.

Innovatively Established Analysis Method for Lipoprotein Profiles Based on High-Performance Anion-Exchange Liquid Chromatography

Separation analysis of lipoprotein classes have various methods, including ultracentrifugation, electrophoresis, and gel permeation chromatography (GPC). All major lipoprotein classes can be separated via ultracentrifugation, but performing the analysis takes a long time. Low-density lipoprotein (LDL), intermediate-density lipoprotein (IDL), and very low-density lipoprotein (VLDL) in patient samples cannot be sufficiently separated via electrophoresis or GPC. Thus, we established a new method [anion-exchange high-performance liquid chromatography (AEX-HPLC)] by using HPLC with an AEX column containing nonporous gel and an eluent containing chaotropic ions. AEX-HPLC can separate five lipoprotein fractions of high-density lipoprotein (HDL), LDL, IDL, VLDL, and others in human serum, which can be used in substitution for ultracentrifugation method. The method was also approved for clinical use in the public health-care insurance in Japan in 2014. Furthermore, we developed an additional method to measure cholesterol levels of the four leading lipoprotein fractions and two subsequent fractions (i.e., chylomicron and lipoprotein(a)). We evaluated the clinical usefulness of AEX-HPLC in patients with coronary heart disease (CHD), diabetes, and kidney disease and in healthy volunteers. Results indicate that the cholesterol levels in IDL and VLDL measured by AEX-HPLC may be useful risk markers of CHD or diabetes. Furthermore, we developed another new method for the determination of alpha-tocopherol (AT) in lipoprotein classes, and this method is composed of AEX-HPLC for the separation of lipoprotein classes and reverse-phase chromatography to separate AT in each lipoprotein class. The AT levels in LDL were significantly correlated with the lag time to copper ion-induced LDL oxidation, which is an index of oxidation resistance. The application of AEX-HPLC to measure various substances in lipoproteins will be clinically expected in the future.

Diabetic dyslipidemia: evaluation and mechanism

Diabetes is one of the well-established independent risk factors for cardiovascular diseases. Diabetes induces dyslipidemia which is characterized by elevated fasting triglyceride (TG) and reduced high-density lipoprotein-cholesterol (HDL-C), and such diabetic dyslipidemia is a crucial determinant for atherogenesis and atherosclerotic progression in patients with diabetes. Previous measurement methods of lipoproteins have problems including time-consuming (ultracentrifugation) and inaccurate and impossible measurements of TG-rich lipoproteins such as chylomicron, intermediate-density lipoprotein (IDL) and very low-density lipoprotein (VLDL). Our developed anion-exchange high-performance liquid chromatography (AEX-HPLC) can measure all fractions of lipoproteins accurately. Our studies using AEX-HPLC showed that IDL and VLDL in type 2 diabetes were higher than non-diabetic subjects, and IDL and VLDL were higher in the order of type 2 diabetic patients with obesity, type 2 diabetic patients without obesity, and non-diabetic subjects. Here, we also describe the underlying mechanisms for development of diabetic dyslipidemia.

Beneficial Effects of Adiponectin on Glucose and Lipid Metabolism and Atherosclerotic Progression: Mechanisms and Perspectives

Circulating adiponectin concentrations are reduced in obese individuals, and this reduction has been proposed to have a crucial role in the pathogenesis of atherosclerosis and cardiovascular diseases associated with obesity and the metabolic syndrome. We focus on the effects of adiponectin on glucose and lipid metabolism and on the molecular anti-atherosclerotic properties of adiponectin and also discuss the factors that increase the circulating levels of adiponectin. Adiponectin reduces inflammatory cytokines and oxidative stress, which leads to an improvement of insulin resistance. Adiponectin-induced improvement of insulin resistance and adiponectin itself reduce hepatic glucose production and increase the utilization of glucose and fatty acids by skeletal muscles, lowering blood glucose levels. Adiponectin has also β cell protective effects and may prevent the development of diabetes. Adiponectin concentration has been found to be correlated with lipoprotein metabolism; especially, it is associated with the metabolism of high-density lipoprotein (HDL) and triglyceride (TG). Adiponectin appears to increase HDL and decrease TG. Adiponectin increases ATP-binding cassette transporter A1 and lipoprotein lipase (LPL) and decreases hepatic lipase, which may elevate HDL. Increased LPL mass/activity and very low density lipoprotein (VLDL) receptor and reduced apo-CIII may increase VLDL catabolism and result in the reduction of serum TG. Further, adiponectin has various molecular anti-atherosclerotic properties, such as reduction of scavenger receptors in macrophages and increase of cholesterol efflux. These findings suggest that high levels of circulating adiponectin can protect against atherosclerosis. Weight loss, exercise, nutritional factors, anti-diabetic drugs, lipid-lowering drugs, and anti-hypertensive drugs have been associated with an increase of serum adiponectin level.

Effectiveness of Low to Moderate Physical Exercise Training on the Level of Low-Density Lipoproteins: A Systematic Review

Background

Regular exercise reduces risk factors associated with cardiovascular disease (CVD). Elevated low-density lipoprotein (LDL) contributes to atherosclerosis formation, which is associated with an increased risk of CVD. The relationship between exercise therapy and lipid levels has been widely studied, but it is established that high-intensity exercise improves lipid profile. However, the effectiveness of low- to moderate-intensity exercise in altering LDL levels is controversial. This review aims to identify the current evidence and existing gaps in literature in this area.

Methods

We searched and reviewed various randomized controlled clinical trials in the electronic databases EMBASE, CINAHL, the Web of Science, Cochrane, Pedro, Medline (PubMed), and Google Scholar using the keywords “low and moderate aerobic training,” “exercise”, “low-density lipoproteins,” “cholesterol,” “atherosclerosis,” and “coronary artery diseases markers.” We included studies that involved low- and/or moderate-intensity exercise training in apparently healthy adults over a period of 8 weeks and its effect on LDL levels. We selected a total of 11 studies from 469; nine were randomized controlled trials and two were systematic reviews.

Results

Aerobic exercise of both low and moderate intensity resulted in a significant reduction of total cholesterol. Effects on low-density lipoprotein levels were significant, and most of the studies showed changes in the level without significant relation to the type of exercise. At the same time, exercise improved the health status and physical fitness of all the participants in the included studies.

Conclusion

This study found that low- and moderate-intensity exercise and low-density lipoprotein levels were not proven to be significantly related, except in a few studies that were limited to dyslipidemia population.

Adiponectin response to supervised aerobic training in type II diabetic patients

Background: Cross-sectional studies have linked decreased adiponectin levels with several metabolic traits, including insulin resistance, dyslipidemia, and metabolic syndrome. Previous studies conducted to investigate the effects of acute or chronic exercise on the serum adiponectin have produced conflicting and controversial results.

Objective: To investigate the effect of supervised aerobic training of moderate intensity on the total serum levels of adiponectin and its relationship to insulin resistance and body weight in subjects with type 2 diabetes (DM2).

Methods: Thirty-five patient participants diagnosed as having DM2 mellitus for more than 5 years with normal or near normal body weight took part in this study. The diagnosis of DM was based on the American Diabetes Association criteria for type 2 diabetes mellitus. Serum levels of blood glucose, insulin, total adiponectin, high molecular weight adiponectin, and insulin resistance were determined before and after a 12-week program of supervised moderate intensity aerobic training.

Results: Twelve weeks of supervised moderate intensity aerobic training produced a significant reduction of fasting blood sugar, fasting insulin, glycosylated hemoglobin, and insulin resistance in male subjects with DM2. By contrast, a significant increase in the total serum adiponectin and high molecular weight adiponectin has been reported. There was no significant correlation between the reduction of the body mass index, insulin resistance, and the increase of the total serum adiponectin or high molecular weight adiponectin.

Conclusion: Prolonged exercise training of at least moderate intensity improves levels of adiponectin and insulin sensitivity in men with type 2 diabetes.

Body Mass Index Modifies an Association between Self-Reported Regular Exercise and Proteinuria

AIM

Regular exercise habits are well-known to exert a favorable effect on the metabolic syndrome, which may cause proteinuria and chronic kidney disease (CKD). However, it remains unknown if exercise exerts a favorable effect on proteinuria and kidney dysfunction. The aim of this study was to reveal the association between exercise and the prevalence of proteinuria and kidney dysfunction and the attenuation by obesity.

METHODS

This study was a cross-sectional cohort study that included 292,013 participants who underwent the Specific Health Check and Guidance in Japan. The exercise score (range 0-3) was based on the number of positive answers to three questions regarding exercise habits. The outcome was defined as urinary protein detected by a dipstick test and kidney dysfunction [estimated glomerular filtration rate (GFR) less than 45 ml/min/1.73 m(2)].

RESULTS

The exercise score was significantly associated with the prevalence of proteinuria in both males [vs. exercise score 0; exercise score 1, multivariate-adjusted odds ratio 0.86 (95% confidence interval 0.81-0.92), P<0.001; exercise score 2, 0.84 (0.79-0.90), P<0.001; exercise score 3, 0.77 (0.72-0.82), P<0.001] and females (same as in males). After the male subjects were divided into quintiles according to body mass index (BMI) in more than three groups (22.9<BMI<24.1), there was no significant association between the exercise score and the prevalence of proteinuria. In females, a higher exercise score was associated with a lower prevalence of proteinuria, regardless of BMI. The association between the exercise score and kidney dysfunction was as similar as that between the exercise score and proteinuria, except the attenuation of BMI.

CONCLUSION

Exercise may associate with a lower prevalence of proteinuria and kidney dysfunction, and a high BMI may attenuate this association between exercise and proteinuria in male subjects.

Exercise Training and Insulin Resistance: A Current Review

There is a general perception that increased physical activity will improve glucose homeostasis in all individuals. While this is an attractive concept, this conclusion may be overly simplistic and even misleading. The topic was reviewed extensively over 30 years ago and it was concluded that acute exercise enhances glucose uptake. However, in some cases the chronic influence of interventions utilizing exercise may have little effect on glucose metabolism. Moreover, insulin resistance often returns to near baseline levels within a couple of days following cessation of the exercise bout; leaving the overall effectiveness of the intervention in question. Since improving glucose homeostasis should be the focal endpoint of any intervention designed to mitigate the overwhelming degree of insulin resistance in individuals at risk for metabolic disease, it is essential to evaluate the key components of a successful approach.

Ten weeks of aerobic training does not result in persistent changes in VLDL triglyceride turnover or oxidation in healthy men

OBJECTIVE

Very low density lipoprotein triglyceride (VLDL-TG) and free fatty acids (FFA) constitute a substantial proportion of human energy supply both at rest and during exercise. Exercise acutely decreases VLDL-TG concentration, and VLDL-TG clearance is increased after an exercise bout. However, the effects of long-term training are not clear.

DESIGN

The aim was to investigate long-term effects of training by direct assessments of VLDL-TG and palmitate kinetics and oxidation in healthy lean men (n=9) at rest, before and after a 10-week training program, compared with a non-training control group (n=9).

METHODS

VLDL-TG kinetics were assessed by a primed constant infusion of [1-14C]VLDL-TG, and VLDL-TG oxidation by specific activity (14CO2) in expired air. The metabolic study days were placed 60-72 h after the last exercise bout.

RESULTS

Palmitate kinetics and oxidation were assessed by a 2 h constant infusion of [9,10-(3)H]palmitate. In the training group (n=9), maximal oxygen uptake increased significantly by ≈20% (P<0.05), and the insulin sensitivity (assessed by the hyperinsulinemic-euglycemic clamp) improved significantly (P<0.05). Despite these metabolic improvements, no changes were observed in VLDL-TG secretion, clearance, or oxidation or in palmitate kinetics.

CONCLUSION

We conclude that 10 weeks of exercise training did not induce changes in VLDL-TG and palmitate kinetics in healthy lean men.

Atherogenic subfractions of lipoproteins in the treatment of metabolic syndrome by physical activity and diet - the RESOLVE trial

Background

We aimed to comprehensively evaluate lipoprotein profile including lipid particle size following a lifestyle intervention in metabolic syndrome (MetS) volunteers and to assess the associations between lipoprotein subfractions and carotid-intima-media-thickness (CIMT) – a surrogate indicator of atherogenesis.

Methods

100 participants (50–70 years) from the RESOLVE trial, underwent a one-year follow-up beginning with a three-week residential program combining high exercise volume (15-20 h/week), restrictive diet (-500 kcal/day), and education. For baseline references, 40 aged-matched healthy controls were recruited. Independent associations between subfractions of lipoproteins and CIMT were evaluated using a generalized estimating equations model accounting for variation in correlations between repeated measures. The lipoprotein subfractions profile was assessed using Lipoprint® electrophoresis allowing to separate: the very low-density lipoprotein (VLDL) fraction, then the intermediate-density lipoprotein (IDL) C, B and A, the low-density lipoprotein (LDL) with subfractions 1 and 2 as large LDL and subfractions 3 to 7 as small dense LDL (sdLDL), and the high density lipoprotein (HDL) subfractions categorized into large, intermediate, and small HDL. Apolipoproteins A1 and B were also measured.

Results

78 participants completed the program. At baseline, apolipoproteins B/A1, VLDL, sdLDL and small HDL were higher in MetS than in healthy controls; IDL, LDL size, large and intermediate HDL were lower. Despite time-related regains during the follow-up, lipoprotein subfractions traditionally involved in cardiovascular risk, such as sdLDL, improved immediately after the residential program with values closest to those of healthy controls. CIMT improved throughout the lifestyle intervention. Using a generalized estimating equations model, none of the subfractions of lipoproteins nor apolipoproteins were linked to CIMT.

Conclusions

Lipoprotein subfractions traditionally involved in CVR, decreased after the 3-week residential program. During a 12 month follow-up, the time-related regains remained closer to the values of healthy controls than they were at baseline. CIMT improved throughout the lifestyle intervention. However, we failed to demonstrate a link between some lipoprotein subfractions and the atherogenicity directly measured from the wall thickness of arteries (CIMT). Further investigations are required to explore the atherogenicity of lipoprotein subfractions.

Trial registration

NCT00917917

Effect of exercise on serum adiponectin and lipoprotein levels in male rat

The effect of exercise and recovery period on adiponectin level is not still cleared. The aim of this study was to evaluate the effect of different intensities of running on serum adiponectin and lipoproteins levels in male rats. In this experimental study, one hundred and sixty rats aged 2 months years old (250 +/- 5 g) were randomly assigned into four groups including the control and the 3 groups running at the speeds of 18, 24 and 30 m min(-1) for 30 min. Serum adiponectin, Low Density Lipoprotein (LDL) and High Density Lipoprotein (HDL) levels were evaluated in four stages: Before running, immediately, 30 min and 5 h after the running finished. In different stages, 10 rats of each group were anesthetized and blood were collected from abdominal aorta. Serum adiponectin concentrations increased immediately after running in the rats ran with the speeds of 18, 24 and 30 m min(-1) in 30 min (p < 0.05). Thirty minute after running, serum adiponectin concentrations did not change only in the rats ran with the speed of 18 m min(-1) (p = 0.46). Five hours after running, serum adiponectin concentrations approximately reached into the before running levels in the rats ran with the speeds of 18, 24 and 30 m min(-1) (p < 0.05). There was no significant difference in serum LDL and HDL concentrations between and within rat groups (p > 0.05). Serum adiponectin concentrations rose when the running intensities in one exercise session increased in male rats. During recovery period, serum adiponectin concentrations decreased with the same pattern in different exercise intensities.

Roles of adiponectin and oxidative stress in obesity-associated metabolic and cardiovascular diseases

The recent increase in populations with obesity is a worldwide social problem, and the enhanced susceptibility of obese people to metabolic and cardiovascular diseases has become a growing health threat. An understanding of the molecular basis for obesity-associated disease development is required to prevent these diseases. Many studies have revealed that the mechanism involves various bioactive molecules that are released from adipose tissues and designated as adipocytokines/adipokines. Adiponectin is an adipocytokine that exerts insulin-sensitizing effects in the liver and skeletal muscle via adenosine monophosphate-activated protein kinase and proliferator-activated receptor α activation. Additionally, adiponectin can suppress atherosclerosis development in vascular walls via various anti-inflammatory effects. In contrast, oxidative stress is a harmful factor that systemically increases during obesity and promotes the development of diabetes, atherosclerosis, and various other diseases. In obese mice, oxidative stress is enhanced in adipose tissue before diabetes development, but not in the liver, skeletal muscle, and aorta, suggesting that in obesity, adipose tissue may be a major source of reactive oxygen species (ROS). ROS suppress adiponectin production in adipocytes. Treatment of obese mice with anti-oxidative agents improves insulin resistance and restores adiponectin production. Recent studies have demonstrated that adiponectin protects against oxidative stress-induced damage in the vascular endothelium and myocardium. Thus, decreased circulating adiponectin levels and increased oxidative stress, which are closely linked to each other, should be deeply involved in obesity-associated metabolic and cardiovascular disease pathogenesis.

Increased blood cholesterol after a high saturated fat diet is prevented by aerobic exercise training

A high saturated fatty acids diet (HSFAD) deteriorates metabolic and cardiovascular health while aerobic training improves them. The aim of this study was to investigate in physically inactive and overweight people if 2 weeks of HSFAD leads to hyperlipemia or insulin resistance and if concurrent aerobic exercise training counteracts those effects. Fourteen overweight (body mass index, 27.5 ± 0.6 kg·m−2), healthy, young individuals (aged 24.8 ± 1.8 years) were randomly assigned to a diet (D) or a diet plus exercise (D + E) group. During 14 consecutive days both groups increased dietary saturated fatty acids from 31 ± 10 to 52 ± 14 g·day−1(p < 0.001) while maintaining total fat intake. Concurrent to the diet, the D + E group underwent 11 cycle-ergometer sessions of 55 min at 60% peak oxygen uptake (V˙O2peak). Before and after intervention, insulin sensitivity and body composition were estimated, and blood lipids, resting blood pressure, and V̇O2peakwere measured. Body weight and composition, plasma free fatty acids composition and concentration, and insulin sensitivity remained unchanged in both groups. However, post-intervention total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) increased above pre-intervention values in the D group (147 ± 8 to 161 ± 9 mg·dL−1, p = 0.018 and 71 ± 10 to 82 ± 10 mg·dL−1, p = 0.034, respectively). In contrast, in the D + E group, TCand LDL-C remained unchanged (153 ± 20 to 157 ± 24 mg·dL−1and 71 ± 21 to 70 ± 25 mg·dL−1). Additionally, the D + E group lowered systolic blood pressure (6 ± 2 mm Hg, p = 0.029) and increased V̇O2peak(6 ± 2 mL·kg−1·min−1, p = 0.020). Increases in TCand LDL-C concentration induced by 14 days of HSFAD can be prevented by concurrent aerobic exercise training, which, in addition, improves cardiorespiratory fitness.

Changes in body weight, C-reactive protein, and total adiponectin in non-obese women after 12 months of a small-volume, home-based exercise program

OBJECTIVE

Our objective was to evaluate the effects of small-volume, home-based exercise combined with slight caloric restriction on the inflammatory markers C-reactive protein and adiponectin.

METHODS

In total, 54 women were randomly assigned to one of two groups for exercise intervention: the control or home-based exercise groups. Weight, waist and hip circumferences, and inflammatory markers were measured at baseline and after 6 and 12 months. Women allocated to the home-based exercise group received a booklet explaining the physical exercises to be practiced at home at least 3 times per week, 40 minutes per session, at low-to-moderate intensity. All participants received dietary counseling aimed at reducing caloric intake by 100-300 calories per day, with a normal distribution of macro-nutrients (26-28% of energy as fat). Clinicaltrials.gov: NCT01206413 RESULTS: The home-based exercise group showed a significantly greater reduction in weight and body mass index at six months, but no difference between groups was observed thereafter. With regard to the inflammatory markers, a greater but non-statistically significant reduction was found for C-reactive protein in the home-based exercise group at six months; however, this difference disappeared after adjusting for weight change. No differences in adiponectin were found at the 6- or 12-month follow-up.

CONCLUSION

Small-volume, home-based exercise did not promote changes in inflammatory markers independent of weight change.

Fasting remnant lipoproteins can predict postprandial hyperlipidemia

BACKGROUND

Hypertriglyceridemia and postprandial hyperlipidemia is thought to play an important role in atherosclerosis, but to select patients at high-risk for cardiovascular diseases is difficult with triglycerides (TG) alone in these patients.

METHODS

To predict postprandial hyperlipidemia without inconvenient test meal loading, we examined lipid concentrations before and after test meal loading and fasting adiponectin, and investigated which of these other than TG were significant during the fasting period in 45 healthy individuals (men: women, 26:19).

RESULTS

TG, remnant-like particle-cholesterol and -triglyceride (RemL-C, RLP-C, and RLP-TG), and TG/apolipoprotein(apo)B were significantly elevated after loading and fasting values significantly and positively correlated with incremental area under the curve (iAUC) (r=0.80, r=0.79, r=0.63, r=0.58, r=0.54; p<0.0001). Fasting adiponectin positively correlated with fasting high-density lipoprotein-cholesterol (r=0.43, p<0.005) and apoA-I (r=0.34, p<0.05), and negatively correlated with iAUC of TG, RemL-C, RLP-C, RLP-TG, and TG/apoB (r=-0.37, r=-0.41, r=-0.37, r=-0.36, r=-0.37; p<0.05). We constructed the model of multivariable linear regression analysis without fasting TG. In the sex-, BMI-, age-, and waist circumference-adjusted analysis of postprandial TG elevation 2 h after test meal loading in all participants, RemL-C, RLP-C, RLP-TG, and TG/apoB were significant factors, but adiponectin was not.

CONCLUSION

Fasting triglyceride-rich lipoprotein-related values, especially RemL-C, RLP-C, RLP-TG, and TG/apoB are useful predictors of postprandial hyperlipidemia in young healthy individuals. Although fasting adiponectin concentration correlated with the iAUCs for TG, RemL-C, RLP-C, RLP-TG, and TG/apoB, it was not a significant predictor of postprandial hyperlipidemia in multivariable linear regression analysis.

Physical activity and blood lipids and lipoproteins in dialysis patients

The relationship between physical activity and blood lipids and lipoproteins in dialysis patients is reviewed in the context of the potentially confounding factors such as nutritional intake, cigarette smoking, obesity, alcohol intake, and physical activity levels in the general population and additional confounding factors such as mode of dialysis and diabetes in dialysis patients. The known associations in the general population of physical activity with high-density-lipoprotein cholesterol subfractions and apolipoprotein A-I are more pronounced in hemodialysis patients than in peritoneal dialysis patients even after adjusting for these confounding factors. Examining studies on the effects of physical activity on blood lipids and lipoproteins, the most consistent observation is the noted decrease in triglycerides and increase in high-density-lipoprotein cholesterol and insulin sensitivity in hemodialysis patients. The changes in lipids and lipoproteins in hemodialysis patients could be caused by changes in activity levels of lipoprotein lipase, insulin sensitivity, and/or glucose metabolism. Future research investigating the relationship between physical activity and blood lipids and lipoproteins in dialysis patients should direct research towards the underlying mechanisms for changes in blood lipids and lipoproteins.

Cardiovascular benefits of exercise

Regular physical activity during leisure time has been shown to be associated with better health outcomes. The American Heart Association, the Centers for Disease Control and Prevention and the American College of Sports Medicine all recommend regular physical activity of moderate intensity for the prevention and complementary treatment of several diseases. The therapeutic role of exercise in maintaining good health and treating diseases is not new. The benefits of physical activity date back to Susruta, a 600 BC physician in India, who prescribed exercise to patients. Hippocrates (460–377 BC) wrote “in order to remain healthy, the entire day should be devoted exclusively to ways and means of increasing one’s strength and staying healthy, and the best way to do so is through physical exercise.” Plato (427–347 BC) referred to medicine as a sister art to physical exercise while the noted ancient Greek physician Galen (129–217 AD) penned several essays on aerobic fitness and strengthening muscles. This article briefly reviews the beneficial effects of physical activity on cardiovascular diseases.

Adiponectin promotes the migration of circulating angiogenic cells through p38-mediated induction of the CXCR4 receptor

AIMS

Adiponectin (adipo) and exercise training (ET) contribute to the maintenance of a normal vascular tone by influencing vascular NO bioavailability and concentration and function of circulating angiogenic cells (CAC). The molecular mechanisms are only partially understood. Aim of the present study was to elucidate the effects of adipo on CAC migration and the underlying signaling pathways. Furthermore, the impact of ET on adiponectin-mediated CAC migration was investigated.

METHODS AND RESULTS

CACs were isolated from peripheral blood and exposed to different adipo concentrations. Adipo (5μg/ml) enhanced the ability of CACs to migrate following an SDF-1 gradient by 345%. This was associated with a significant increase in CXCR4 expression on the surface of CACs as compared to control (10.1 ± 1.5 vs. 33.2 ± 4.5% CXCR4 positive cells, p<0.05). Adiponectin-induced CAC migration and CXCR4-upregulation were mediated through adipo-receptor 1 (AdipoR1) and blocked by an inhibitor of PI3-kinase, p38MAP kinase and NFκb. Adipo-stimulated migration of CACs, CXCR4 expression and p38MAPK-activation is impaired in patients with coronary artery disease (CAD). ET over 4 weeks partially corrects adiponectin-stimulated CAC migration and CXCR4 expression in patients with CAD (n=10). No change was observed in the control group (n=10).

CONCLUSION

Adipo improves the migratory capacity of CACs in response to SDF1, partially through an upregulation of CXCR4. This is mediated through a pathway that involves binding of adipo to the AdipoR1 and subsequent PI3kinase/p38MAPK/ NFκb activation. In addition ET corrects the adiponectin responsiveness of CACs, and thereby might promote endogenous repair of damaged endothelium.

Exercise-associated generation of PPARγ ligands activates PPARγ signaling events and upregulates genes related to lipid metabolism

The aim of the present study was to test the hypotheses that exercise is associated with generation of peroxisome proliferator-activated receptor-γ (PPARγ) ligands in the plasma and that this may activate PPARγ signaling within circulating monocytes, thus providing a mechanism to underpin the exercise-induced antiatherogenic benefits observed in previous studies. A cohort of healthy individuals undertook an 8-wk exercise-training program; samples were obtained before (Pre) and after (Post) standardized submaximal exercise bouts (45 min of cycling at 70% of maximal O2 uptake, determined at baseline) at weeks 0, 4, and 8. Addition of plasma samples to PPARγ response element (PPRE)-luciferase reporter gene assays showed increased PPARγ activity following standardized exercise bouts (Post/Pre = 1.23 ± 0.10 at week 0, P < 0.05), suggesting that PPARγ ligands were generated during exercise. However, increases in PPARγ/PPRE-luciferase activity in response to the same standardized exercise bout were blunted during the training program (Post/Pre = 1.18 ± 0.14 and 1.10 ± 0.10 at weeks 4 and 8, respectively, P > 0.05 for both), suggesting that the relative intensity of the exercise may affect PPARγ ligand generation. In untrained individuals, specific transient increases in monocyte expression of PPARγ-regulated genes were observed within 1.5–3 h of exercise (1.7 ± 0.4, 2.6 ± 0.4, and 1.4 ± 0.1 fold for CD36, liver X receptor-α, and ATP-binding cassette subfamily A member 1, respectively, P < 0.05), with expression returning to basal levels within 24 h. In contrast, by the end of the exercise program, expression at the protein level of PPARγ target genes had undergone sustained increases that were not associated with an individual exercise bout (e.g., week 8 Pre/ week 0 Pre = 2.79 ± 0.61 for CD36, P < 0.05). Exercise is known to upregulate PPARγ-controlled genes to induce beneficial effects in skeletal muscle (e.g., mitochondrial biogenesis and aerobic respiration). We suggest that parallel exercise-induced benefits may occur in monocytes, as monocyte PPARγ activation has been linked to beneficial antidiabetic effects (e.g., exercise-induced upregulation of monocytic PPARγ-controlled genes is associated with reverse cholesterol transport and anti-inflammatory effects). Thus, exercise-triggered monocyte PPARγ activation may constitute an additional rationale for prescribing exercise to type 2 diabetes patients.

The impact of one session resistance exercise on plasma adiponectin and RBP4 concentration in trained and untrained healthy young men

We designed this study, to investigate the predicting effect of a single resistance exercise session on serum level of RBP4 and adiponectin in trained and untrained subjects and to evaluate whether regular training may affect the response of these adipokines to exercise. Thirty four healthy young male students including 19 trained and 15 untrained participated in this study; each group was then randomly assigned to intervention and control groups. The exercise session prolonged 120 minutes intensive resistance program at 70%-80% of 1RM. The blood samples were collected just before the start of training program and 4 hours post exercise to evaluate concentration of adiponectin, RBP4 and CRP as well as other metabolic markers. The serum level of adiponectin, RBP4 and CRP was not significantly different between trained and untrained groups at baseline. More over four hours post exercise adipokines concentration and CRP didn't differ between groups. Adjusted regression model showed, basal adiponectin (β=0.59, p=<0.001) and HDL cholesterol (β=0.28, p=0.09) were the main predictors of post exercise adiponectin concentration. In addition, the basic level of RBP4 appeared to be the only predictor of after exercise RBP4 concentration (β=0.46, p=0.02). Neither one session of high intensity resistance exercise nor long term training had predicting effect on post exercise adiponectin and RBP4 concentration in healthy young men. In the other hand, the beneficial effect of acute resistance exercise training may not be reflected by changes in adiponectin, RBP4 and CRP concentration in healthy young individual no matter they trained or untrained.