Effects of walking on low-grade inflammation and their implications for Type 2 Diabetes

Beyond muscles: Investigating immunoregulatory myokines in acute resistance exercise - A systematic review and meta-analysis

Myokines, released from the muscle, enable communication between the working muscles and other tissues. Their release during physical exercise is assumed to depend on immune-hormonal-metabolic interactions concerning mode (endurance or resistance exercise), duration, and intensity. This meta-analysis aims to examine the acute changes of circulating myokines inducing immunoregulatory effects caused by a bout of resistance exercise and to consider potential moderators of the results. Based on this selection strategy, a systematic literature search was conducted for resistance exercise intervention studies measuring interleukin (IL-) 6, IL-10, IL-1ra, tumor necrosis factor (TNF-) α, IL-15, IL-7, transforming growth factor (TGF-) β1, and fractalkines (FKN) before and immediately after resistance exercise in healthy individuals. Random-effects meta-analysis was performed for each myokine. We identified a moderate positive effect of resistance exercise for IL-6 and IL-1ra. Regarding IL-15 and TNF-α, small to moderate effects were found. For IL-10, no significant effect was observed. Due to no data, meta-analyses for IL-7, TGF-β1, and FKN could not be performed. No moderators (training status, type of exercise, risk of bias, age, sex, time of day, exercise volume, exercise intensity, exercise dose) of the results were detected for all tested myokines. Taken together, this systematic review and meta-analysis showed immediate positive effects of an acute resistance exercise session on IL-6, IL-1ra, TNF-α, and IL-15 levels.

Interpreting 'anti-inflammatory' cytokine responses to exercise: focus on interleukin-10

Circulating concentrations of canonically pro- and anti-inflammatory cytokines are commonly measured when evaluating the anti-inflammatory effects of exercise. An important caveat to interpreting systemic cytokine concentrations as evidence for the anti-inflammatory effects of exercise is the observed dissociation between circulating cytokine concentrations and cytokine function at the tissue/cellular level. The dichotomization of cytokines as pro- or anti-inflammatory also overlooks the context dependence of cytokine function, which can vary depending on the physiological state being studied, the cytokine's cellular source/target, and magnitude of cytokine responses. We re-evaluate our current understanding of anti-inflammatory cytokine responses to exercise by highlighting nuances surrounding the interpretation of altered systemic cytokine concentrations as evidence for changes in inflammatory processes occurring at the tissue/cellular level. We highlight the lesser known pro-inflammatory and immunostimulatory actions of the prototypical anti-inflammatory cytokine, interleukin (IL)-10, including the potentiation of interferon gamma production during endotoxaemia, CD8⁺ T cell activation in tumour bearing rodents and cancer patients in vivo, and CD8⁺ T lymphocyte and natural killer cell activation in vitro. IL-10's more well-established anti-inflammatory actions can also be blunted following exercise training and under chronic inflammatory states such as type 2 diabetes (T2D) independently of circulating IL-10 concentrations. The resistance to IL-10's anti-inflammatory action in T2D coincides with blunted STAT3 phosphorylation and can be restored with small-molecule activators of IL-10 signalling, highlighting potential therapeutic avenues for restoring IL-10 action. We posit that inferences based on altered circulating cytokine concentrations alone can miss important functional changes in cytokine action occurring at the tissue/cellular level.

Association of Inflammatory Metabolic Activity of Psoas Muscle and Acute Myocardial Infarction: A Preliminary Observational Study with 18F-FDG PET/CT

Inflamed skeletal muscle promotes chronic inflammation in atherosclerotic plaques, thereby contributing to the increased risk of coronary artery disease (CAD). In this study, we evaluated the metabolic activity of psoas muscle, using ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT), and its association with carotid artery inflammation and acute myocardial infarction (AMI). In total, 90 participants (32 AMI, 33 chronic stable angina (CSA), and 25 control) were enrolled in this prospective study. Metabolic activity of skeletal muscle (SM) was measured by using maximum standardized uptake value (SUVmax) of psoas muscle, and corresponding psoas muscle area (SM area) was also measured. Carotid artery inflammation was evaluated by using the target-to background ratio (TBR) of carotid artery. SM SUVmax was highest in AMI, intermediate in CSA, and lowest in control group. SM SUVmax was significantly correlated with carotid artery TBR and systemic inflammatory surrogate markers. Furthermore, SM SUVmax was independently associated with carotid artery TBR and showed better predictability than SM area for the prediction of AMI. Metabolic activity of psoas muscle assessed by ¹⁸F-FDG PET/CT was associated with coronary plaque vulnerability and synchronized with the carotid artery inflammation in the participants with CAD. Furthermore, it may also be useful to predict AMI.

Early temporal prediction of Type 2 Diabetes Risk Condition from a General Practitioner Electronic Health Record: A Multiple Instance Boosting Approach

Early prediction of target patients at high risk of developing Type 2 diabetes (T2D) plays a significant role in preventing the onset of overt disease and its associated comorbidities. Although fundamental in early phases of T2D natural history, insulin resistance is not usually quantified by General Practitioners (GPs). Triglyceride-glucose (TyG) index has been proven useful in clinical studies for quantifying insulin resistance and for the early identification of individuals at T2D risk but still not applied by GPs for diagnostic purposes. The aim of this study is to propose a multiple instance learning boosting algorithm (MIL-Boost) for creating a predictive model capable of early prediction of worsening insulin resistance (low vs high T2D risk) in terms of TyG index. The MIL-Boost is applied to past electronic health record (EHR) patients' information stored by a single GP. The proposed MIL-Boost algorithm proved to be effective in dealing with this task, by performing better than the other state-of-the-art ML competitors (Recall from 0.70 and up to 0.83). The proposed MIL-based approach is able to extract hidden patterns from past EHR temporal data, even not directly exploiting triglycerides and glucose measurements. The major advantages of our method can be found in its ability to model the temporal evolution of longitudinal EHR data while dealing with small sample size and variability in the observations (e.g., a small variable number of prescriptions for non-hospitalized patients). The proposed algorithm may represent the main core of a clinical decision support system.

M2 macrophage immunotherapy abolishes glucose intolerance by increasing IL-10 expression and AKT activation

Aim: Glucose intolerance associates with M1/M2 macrophage unbalance. We thus wanted to examine the effect of M2 macrophage administration on mouse model of glucose intolerance. Materials & methods: C57BL/6 mice fed a high-fat diet (HFD) for 12 weeks and then received thrice 20 mg/kg streptozotocin (HFD-GI). Bone marrow-derived stem cells were collected from donor mice and differentiated/activated into M2 macrophages for intraperitoneal administration into HFD-GI mice. Results: M2 macrophage treatment abolished glucose intolerance independently of obesity. M2 macrophage administration increased IL-10 in visceral adipose tissue and serum, but showed no effect on serum insulin. While nitric oxide synthase-2 and arginase-1 remained unaltered, M2 macrophage treatment restored AKT phosphorylation in visceral adipose tissue. Conclusion: M2 macrophage treatment abolishes glucose intolerance by increasing IL-10 and phosphorylated AKT.

Effects of chia (Salvia hispanica L.) on oxidative stress and inflammation in ovariectomized adult female Wistar rats

The present study investigated the influence of chia consumption on inflammation, oxidative stress, and lipid profiles in adult female ovariectomized rats fed a high-fat diet. Forty ovariectomized and 40 intact (SHAM) rats were allocated into 8 groups (n = 10), and each rat received one of the following four diets: standard diet (ST); standard diet + chia (STC); high-fat diet (HF); and high-fat diet + chia (HFC) for 126 days. Biochemical parameters and biomarkers of lipid peroxidation, inflammation, and oxidative stress were evaluated. The mRNA expression levels of PPAR-α, NFκB, TNF-α and Zn-SOD1 were analyzed, as well as those of TNF-α and IL-1β. Chia intake increased HDL cholesterol (HDL-c) and reduced LDL cholesterol (LDL-c) levels. Plasma catalase activity was elevated in the STC group. Concentrations of TBARS were higher in all groups fed HF. PPAR-α mRNA expression was elevated, and levels of NFκB mRNA expression were reduced in the STC group. mRNA expression and protein levels of TNF-α were lower in rats fed the standard diet. Protein levels of IL-1β were reduced in rats fed the standard diet, and the high fat diet with chia. In general, ovariectomy did not influence the inflammatory and oxidative stress parameters. Chia intake improved antioxidant activity by increasing SOD expression, PPAR-α expression, catalase activity, and HDL-c levels. In addition, chia consumption decreased the concentrations of the inflammatory markers IL-1β and LDL-c.

En Balance: The Contribution of Physical Activity to the Efficacy of Spanish Diabetes Education of Hispanic Americans with Type 2 Diabetes

PURPOSE

En Balance, a culturally sensitive diabetes education program, improves glycemic control in Hispanics with type 2 diabetes. The program emphasized diet, physical activity, and other factors important for glycemic control. However, the individual contributions of these education factors are unclear. The purpose of this study is to assess the contribution of physical activity to the success of En Balance in improving the health of Mexican Americans with type 2 diabetes.

METHODS

A retrospective study was conducted with plasma samples collected pre- and post-3-month study. Samples from 58 (18 males and 40 females) Hispanic subjects with type 2 diabetes were analyzed for the concentration of kynurenines, known to decrease in response to exercise. After three months, health outcomes for the active group (decreased kynurenines) and the rest of the cohort were evaluated by paired Wilcoxon signed-rank test.

RESULTS

Half of the subjects had increased kynurenine levels at the end of the educational program. We found that the subjects in the active group with decreased kynurenine concentrations displayed statistically greater improvements in fasting blood glucose, A1C, cholesterol, and triglycerides despite weight loss being higher in the group with increased kynurenine concentrations.

CONCLUSIONS

En Balance participants with decreased kynurenine levels had significantly improved glycemic control. These data suggest that physical activity significantly contributes to the success of the En Balance education program. This analysis indicates that diabetes public health educators should emphasize the benefit of physical activity on glycemic control even in the absence of major weight loss.

Moderate increases in daily step count are associated with reduced IL6 and CRP in women with PCOS

Aims Physical activity has been proposed to be an effective non-pharmacological method of reducing systemic inflammation and therefore may prove particularly efficacious for women with polycystic ovary syndrome (PCOS) who have been shown to have high levels of inflammation and an increased risk of type 2 diabetes (T2DM) and cardiovascular disease (CVD). Therefore, the aim of the present study was to assess whether modest changes in daily step count could significantly reduce levels of inflammatory markers in women with PCOS. Subjects and Methods Sixty-five women with PCOS were assessed at baseline and again at 6 months. All had been provided with an accelerometer and encouraged to increase activity levels. Multivariate linear regression analyses (adjusted for age, ethnicity, baseline step count, change in BMI and change in accelerometer wear-time) were used to assess changes in daily step count against clinical and research biomarkers of inflammation, CVD and T2DM. Results Mean step count/day at baseline was 6337 (±270). An increase in step count (by 1000 steps) was associated with a 13% reduction in IL6 (β: -0.81 ng/L; 95% CI, -1.37, -0.25, P = 0.005) and a 13% reduction in CRP (β: -0.68 mg/L; 95% CI, -1.30, -0.06, P = 0.033). Additionally, there was a modest decrease in BMI (β: 0.20 kg/m2; 95% CI, -0.38, -0.01, P = 0.038). Clinical markers of T2DM and CVD were not affected by increased step count. Conclusions Modest increases in step count/day can reduce levels of inflammatory markers in women with PCOS, which may reduce the future risk of T2DM and CVD.

Diets along with interval training regimes improves inflammatory & anti-inflammatory condition in obesity with type 2 diabetes subjects

Background

Different physical activities and diets change the regulation of inflammations in both type 2 diabetes (T2D) patients and obese individuals, but the effect of both (Physical activity and diet) on pro/anti-inflammations has remained unknown. We investigated pro/anti-inflammations control, cardiovascular function, and total physiological parameters before and after 24 weeks of low volume high intensity interval training (HIIT) on a cycle ergometer along with four dietary regimes in obesity with T2D patients.

Methods

33 non-active obesity T2D patients (BMI ≥ 30) midges (47 yrs. ± 5) were volunteered to participate and randomly divided into three experimental(n = 11) [(1) LCD = low Carbohydrate Diet, (2) LFD = Low Fat Diet and (3) HFD = High Fat Diet)] and one control (n = 9) [ND = normal diet] groups. The whole groups performed underwent 8-week dietary regimes and then performed 3 days/weeks (3 set 10 × 60 s) HIIT on a cycle ergometer for 12 weeks, which followed by a 4-week diet period again. Also, prior to and after 8 weeks diet-12 weeks High Intensity Interval Training (HIIT) and 4 weeks diet 2-h oral glucose tolerance test (OGTT), resting blood pressure, incremental maximal oxygen uptake (VO2peak) cycle ergometer test and blood sample was collected from the subjects in order to measure pro/anti-inflammatory cytokines (IL-6, TNF-α, leptin, resistin, adiponectin, and FGF21).

Results

After 24 weeks of intervention, the results indicated that the highest improvement in the percentage of changes in glucose happened in LCD (-34.76), insulin in ND (+16.43), cholesterol in LCD (-33.35), LDL in LFD (-9.14), HDL in LCD (+41.81), TG in LCD (-40.71), weight in LCD (-12.49) and HOMA-IR in HFD (-6.82). The results also indicated that after 24 weeks of HIIT and diet interventions, highest benefit percentage change IL-6, resistin and leptin occurred in LCD (-32.10, -28.29 and - 53.92, respectively), TNF-α, FGF21 and adiponectin in LFD (-48.06, +55.30 and + 42.32, respectively). However, these changes were observed in other groups.

Conclusions

These results demonstrated that HIIT along with low carbohydrate regimes improves overall cardiovascular parameters and reduce pro-inflammatory markers and increase anti-inflammatory markers in type 2 diabetic patients. Additionally, as with HIIT along with low carbohydrate, HIIT coupled with low fat would improve inflammation markers, though these effects were less significant. These findings suggest that HIIT along with low carbohydrate is a beneficial exercise and dietary strategy in T2D patients.

Physical Activity Levels and Cardiometabolic Risks in Obese African American Adults: A Pilot Intervention Study

Limited information is available regarding the effects of physical activity on risks of cardiometabolic diseases among obese African American adults. We conducted a church-based 12-week weight control and cardiometabolic risk reduction intervention (n=30, 22 females, 56.7±11.4 years old, BMI 37.4±6.7 kg/m2), after which body weight was slightly reduced (98.3±18.4 and 97.3±19 kg, p=.052); body fat percentage was significantly decreased among males (34.7±8.9 to 28.5±8.4 %; p=.049); and walking steps were increased, but not significantly. Among measured cardiometabolic risk biomarkers, hemoglobin A1c (HbA1c) was decreased significantly (6.8±1.1 to 6.1±1.1%; p=.0004) while time spent in sedentary behaviors was associated with less favorable change in total cholesterol (β=11.49, SE=3.55, p=.003) and tumor necrosis factor (TNF-α, β=0.3, SE=0.13, p=.038). Our study shows that adiposity reduction was feasible through a short-term healthy lifestyle program for obese African American adults, and suggests that reducing sedentary behaviors through light physical activity might lead to a decrease in cardiovascular risks.

A system model of the effects of exercise on plasma Interleukin-6 dynamics in healthy individuals: Role of skeletal muscle and adipose tissue

Interleukin-6 (IL-6) has been recently shown to play a central role in glucose homeostasis, since it stimulates the production and secretion of Glucagon-like Peptide-1 (GLP-1) from intestinal L-cells and pancreas, leading to an enhanced insulin response. In resting conditions, IL-6 is mainly produced by the adipose tissue whereas, during exercise, skeletal muscle contractions stimulate a marked IL-6 secretion as well. Available mathematical models describing the effects of exercise on glucose homeostasis, however, do not account for this IL-6 contribution. This study aimed at developing and validating a system model of exercise’s effects on plasma IL-6 dynamics in healthy humans, combining the contributions of both adipose tissue and skeletal muscle. A two-compartment description was adopted to model plasma IL-6 changes in response to oxygen uptake’s variation during an exercise bout. The free parameters of the model were estimated by means of a cross-validation procedure performed on four different datasets. A low coefficient of variation (<10%) was found for each parameter and the physiologically meaningful parameters were all consistent with literature data. Moreover, plasma IL-6 dynamics during exercise and post-exercise were consistent with literature data from exercise protocols differing in intensity, duration and modality. The model successfully emulated the physiological effects of exercise on plasma IL-6 levels and provided a reliable description of the role of skeletal muscle and adipose tissue on the dynamics of plasma IL-6. The system model here proposed is suitable to simulate IL-6 response to different exercise modalities. Its future integration with existing models of GLP-1-induced insulin secretion might provide a more reliable description of exercise’s effects on glucose homeostasis and hence support the definition of more tailored interventions for the treatment of type 2 diabetes.

Higher skeletal muscle mass may protect against ischemic stroke in community-dwelling adults without stroke and dementia: The PRESENT project

Background

It is well known that a low skeletal muscle mass (SMM) is associated with stroke. However, it is unknown whether increasing muscle mass can prevent stroke.

Methods

This community-based cross-sectional study was supported by the regional government. SMM measurements and brain computed tomography was performed in 722 stroke-free and dementia-free subjects (aged 50–75 years). Subjects were divided into quartiles (Q) by SMM, checked using the bioelectrical impedance analysis method (InBody 770, InBody, Seoul, Korea). Odds ratios (ORs) of brain white matter changes/silent infarction (WMC/SI) were calculated. The subjects were then divided into two groups by sex and evaluated.

Results

In the analysis of the four groups, the unadjusted ORs of Q2–Q4 were 0.616 (95% confidence interval [CI], 0.372–1.022; P = 0.061), 0.290 (CI, 0.159–0.530; P < 0.001), and 0.209 (CI, 0.108–0.403; P < 0.001) for the risk of WMC/SI. Adjusted ORs for age, hypertension, diabetes mellitus, education, hypercholesterolemia, and smoking were 0.994 (CI, 0.513–1.740; P = 0.085), 0.669 (CI, 0.329–1.362; P = 0.268), and 0.464 (CI, 0.219–0.984; P = 0.045). In the two–group (dichotomized) analysis, the unadjusted OR for the higher muscle mass groups (Q3 + Q4) was 0.313 (CI, 0.200–0.491; P < 0.001). The adjusted OR was 0.577 (CI, 0.340–0.979; P = 0.042). Considering sex, the adjusted OR were 0.351 (CI, 0.141–0.869; P = 0.024) in men and 0.771 (CI, 0.391–1.519; P = 0.452) in women.

Conclusions

Our findings suggest that increased SMM may protect against WMC/SI, especially in men.