Cellular fibronectin response to supervised moderate aerobic training in patients with type 2 diabetes

Decrease in serum asprosin levels following six weeks of spinning and stationary cycling training in overweight women

OBJECTIVES

Secreted by white adipose tissue, asprosin is a newly recognized adipokine whose physiological function is not well comprehended. This study intended to determine the effect of spinning and stationary cycling on serum asprosin levels in overweight women.

METHODS

Forty-five overweight women with BMI>25 kg/m² in the age range of 30-40 years were assigned randomly to three groups of 15 participants: control, spinning (group cycling with music), and stationary bike (individual pedaling on a stationary bike). The participants performed the exercises three sessions per week for six weeks. Lipid profile and asprosin levels were measured by enzymatic and ELISA methods, respectively. Moreover, the paired t-test and one-way ANOVA were employed to make within-group and between-group comparisons, respectively.

RESULTS

The stationary cycling and spinning exercise groups experienced significant reductions in weight, BMI, serum triglyceride, and asprosin levels from the pretest to the posttest. The control group showed no statistically significant differences. Serum concentrations of total cholesterol and low-density lipoprotein only declined in the spinning group. In this regard, neither the control group nor the stationary bicycle exhibited no significant change over time. The spinning group demonstrated a significant rise in high-density lipoprotein levels, which was not observed in the control group. In addition, there was no significant difference in WHR index between the intervention groups.

CONCLUSIONS

By lowering the serum asprosin level, a spinning exercise program appears to be effective in reducing disorders linked to metabolic diseases in overweight women.

M. Simoes D. Exercise Training-Induced Extracellular Matrix Protein Adaptation in Locomotor Muscles: A Systematic Review

Exercise training promotes muscle adaptation and remodelling by balancing the processes of anabolism and catabolism; however, the mechanisms by which exercise delays accelerated muscle wasting are not fully understood. Intramuscular extracellular matrix (ECM) proteins are essential to tissue structure and function, as they create a responsive environment for the survival and repair of the muscle fibres. However, their role in muscle adaptation is underappreciated and underinvestigated. The PubMed, COCHRANE, Scopus and CIHNAL databases were systematically searched from inception until February 2021. The inclusion criteria were on ECM adaptation after exercise training in healthy adult population. Evidence from 21 studies on 402 participants demonstrates that exercise training induces muscle remodelling, and this is accompanied by ECM adaptation. All types of exercise interventions promoted a widespread increase in collagens, glycoproteins and proteoglycans ECM transcriptomes in younger and older participants. The ECM controlling mechanisms highlighted here were concerned with myogenic and angiogenic processes during muscle adaptation and remodelling. Further research identifying the mechanisms underlying the link between ECMs and muscle adaptation will support the discovery of novel therapeutic targets and the development of personalised exercise training medicine.

Aerobic Physical Exercise Improves Exercise Tolerance and Fasting Glycemia Independent of Body Weight Change in Obese Females

Obesity is associated with increased risk of several chronic diseases and the loss of disease-free years, which has increased the focus of much research for the discovery of therapy to combat it. Under healthy conditions, women tend to store more fat in subcutaneous deposits. However, this sexual dimorphism tends to be lost in the presence of comorbidities, such as type 2 diabetes mellitus (T2DM). Aerobic physical exercise (APE) has been applied in the management of obesity, however, is still necessary to better understand the effects of APE in obese female. Thus, we investigated the effect of APE on body weight, adiposity, exercise tolerance and glucose metabolism in female ob/ob mice. Eight-weeks-old female wild-type C57BL/6J and leptin-deficient ob/ob mice (Lep^ob) were distributed into three groups: wild-type sedentary group (Wt; n = 6), leptin-deficient sedentary group (Lep^obS; n = 5) and leptin-deficient trained group (Lep^obT; n = 8). The Lep^obT mice were subjected to 8 weeks of aerobic physical exercise (APE) at 60% of the maximum velocity achieved in the running capacity test. The APE had no effect in attenuating body weight gain, and did not reduce subcutaneous and retroperitoneal white adipose tissue (SC-WAT and RP-WAT, respectively) and interscapular brown adipose tissue (iBAT) weights. The APE neither improved glucose intolerance nor insulin resistance in the Lep^obT group. Also, the APE did not reduce the diameter or the area of RP-WAT adipocytes, but the APE reduced the diameter and the area of SC-WAT adipocytes, which was associated with lower fasting glycemia and islet/pancreas area ratio in the Lep^obT group. In addition, the APE increased exercise tolerance and this response was also associated with lower fasting glycemia in the Lep^obT group. In conclusion, starting APE at a later age with a more severe degree of obesity did not attenuate the excessive body weight gain, however the APE promoted benefits that can improve the female health, and for this reason it should be recommended as a non-pharmacological therapy for obesity.

Cellular Fibronectin Containing Extra Domain A Causes Insulin Resistance via Toll-like Receptor 4

We determined the role of cellular fibronectin (CFN) containing the alternatively spliced extra domain A (FN-EDA) in causing insulin resistance (IR) through toll-like receptor 4 (TLR4). Circulating FN-EDA level was evaluated in mouse and rat IR models. Specific anti-FN-EDA antibody and TLR4 inhibitor were used to study its role in IR in mice. CFN protein was injected to evaluate TLR4 dependent effect of FN-EDA in IR. Furthermore, FN-EDA was estimated in blood plasma and correlated with demographic and clinical characteristics in healthy human participants (n = 38). High-fat diet feeding significantly increased circulating FN-EDA in both mouse (P = 0.03) and rat (P = 0.02) IR models. Antibody against FN-EDA protected mice from IR by increasing glucose disposal rate following glucose (P = 0.02) and insulin (P = 0.01) tolerance tests. CFN protein injection caused IR, however, TLR4 inhibitor protected the mice from CFN induced IR. Multivariate regression analysis predicted an independent positive correlation between circulating FN-EDA and fasting plasma glucose (P = 0.003) in healthy human participants. In conclusion, FN-EDA may cause IR through TLR4 by decreasing glucose disposal rate following glucose and insulin load. Targeting FN-EDA thus can be considered as a possible therapeutic strategy to delay prediabetes progression to diabetes.

The effect of 12 weeks of aerobic training on serum levels high sensitivity C-reactive protein, tumor necrosis factor-alpha, lipid profile and anthropometric characteristics in middle-age women patients with type 2 diabetes

AIMS

The aim of this study was to investigate the effect of 12 weeks of aerobic training on serum levels of high sensitivity C- reactive protein (hs-CRP), tumor necrosis factor-alpha (TNF-α), lipid profile and anthropometric characteristics in middle-aged women patients with type-2 diabetes.

METHODS

A quasi-experimental study, 20 women patients with type-2 diabetes (mean age, 50.25 ± 4.36 years, Body mass index, 25.51 ± 2.91 kg/m², and body fat percentage 23.67 ± 3.05%) were randomly categorized into two experimental and control groups. The protocol aerobic training included eight-minute jogging and eight-minute running with 75-85 percent maximum heart rate reserve in the first session. Per both sessions, one minute added to running time and it increased up to 32 min after 12 weeks. Blood sampling and anthropometric measurements, 24 h before and 48 h after the last training session were conducted.

RESULT

The result showed a significant reduction in hs-CRP and TNF-α in the experimental than control group (P = 0.01). Exercise training-treated patients showed a significant decrease in TG, LDL and increase HDL in comparison with baseline and the control group (P < .05). The results also showed a significant decrease in weight, body mass index, body fat percentage, and waist-hip ratio (P values 0.02, 0.03, 001, 0.04 respectively) following the 12 weeks aerobic training.

CONCLUSION

It seems that long-term aerobic training, improved some important anthropometric and biochemical parameters in patients with type-2 diabetes. These observations give a new insight into the mechanisms by which aerobic training can reduce the cardiovascular risk in diabetes.