Journal of Exercise & Organ Cross Talk

Abstract Obesity is a major risk factor for metabolic diseases. Subfatin, an adipokine with potential metabolic benefits, is of increasing interest. This study investigated the effects of eight weeks of Moderate-Intensity Interval Training (MIIT) on plasma subfatin levels and body composition in sedentary, obese, middle-aged women. Thirty sedentary women (aged 50-60 years; BMI >30 kg/m²) were purposively selected and randomly assigned to an experimental (n=15) or a control (n=15) group. The experimental group performed an eight-week MIIT program (three sessions/week) at an intensity of 50-75% of heart rate reserve, following the principle of progressive overload. The control group maintained their usual sedentary routine. Fasting plasma subfatin levels were measured via enzyme-linked immunosorbent assay (ELISA), and body composition indices (BMI, body fat percentage [BFP], waist-to-hip ratio [WHR]) were assessed pre- and post-intervention. The MIIT group exhibited a significant increase in plasma subfatin levels (p=0.016) and a significant decrease in BFP (p=0.01) compared to the control group. While positive trends were observed, no significant inter-group differences were found for BMI (p>0.05) or WHR (p=0.095). An eight-week MIIT program effectively elevated plasma subfatin concentration and reduced body fat percentage in sedentary, obese, middle-aged women. These results suggest that MIIT may be a valuable exercise strategy for improving adipokine profile and body composition in this population.

 
 


 

Abstract The prevalence of obesity among children and adolescents is one of the most serious public health challenges of the 21st century. Implementing social distancing policy measures, such as the stay-at-home order, to control the spread of coronavirus disease 2019 (COVID-19) not only has affected lifestyles and weights in children but has also created an obesity-inducing environment, leading to modifications in the patterns of interactions between this age group and their surrounding environment. Therefore, the COVID-19 pandemic has been effective in childhood obesity and its prevalence rate may continue increasing. This narrative review aimed to synthesize evidence from global studies on physical inactivity, and obesity among children and adolescents during COVID-19, and then prescribe an evidence-based home exercise guideline for this age group. The study findings revealed that the COVID-19 restrictions have drastically multiplied physical inactivity and obesity in children. It has been further established that childhood obesity leads to numerous chronic diseases, including diabetes mellitus, cardiovascular diseases (CVDs), psychosomatic disorders, lung diseases, and other metabolic problems in childhood and even as children grow up. Physical activity/exercise at home during and after COVID-19 has been correspondingly demonstrated to mitigate the problems associated with obesity. A wide range of resistance, aerobic, balance, flexibility and other types of exercises have been accordingly shown to protect against the negative effects of the pandemic on child health. Hence, efforts to facilitate such exercises are suggested to continue and be scaled up to prevent childhood obesity and relevant diseases during and after this unusual period.

Abstract The purpose of this research was to conduct a systematic review and meta-analysis on the effect of exercise training on neurotrophin levels in obese and overweight individuals. The research evaluated the effect of exercise training on neurotrophins in the databases of PubMed, Science Direct, Scopus, and Google Scholar with identified keywords among papers published from 2000 onwards. After preliminary screening, full-text studies as well as critical evaluation of the papers meeting the inclusion criteria were analyzed. Finally, 12 studies entered systematic research, and 6 studies entered meta-analysis research. The results show that exercise training has an addictive effect on neurotrophin levels in obese individuals, but this addictive effect is not significant. The present meta-analyze shows that the brain -Derived Neurotrophic Factor (BDNF) response to exercise in obese individuals is increasing, but the increase is not significant (Difference in means = -0.42 pg/ml, P = 0.460). On the other hand, the Nerve Growth Factor (NGF) response to exercise is also increasing which is significant (Z = 2.12, P = 0.034).  Thus, it can be concluded that exercise cannot increase neurotrophins in obese and overweight individuals; although, further studies are needed in this area.

Abstract Daily stair walking is a time-efficient everyday activity that improves cardiorespiratory fitness, muscle strength, body composition, blood pressure, lipid profiles, and is associated with a reduction in all-cause mortality. However, more than one in three adult Europeans is physically inactive in their everyday life and the exemplary current rate of stair walking in Germany is not known. Therefore, 2,521 people were monitored climbing the stairs or using a parallel escalator over a period of one week in an underground train station in Munich, Germany (January 3rd to 9th, 2022). 53.4% were women and 46.6% men, 30.7% (N = 774) were classified as obviously overweight-obese. 9.1% (N = 229) of all people counted used the ascending stairs - these were slightly more male than female and a total of 19 persons who were obviously overweight-obese. On two observation days, the pedestrians' mode of descent (stairs/escalator) was also recorded on 457 people, of whom 28% (N = 128) were categorized as obviously overweight-obese. With an equal gender distribution, 27.8% (N = 127) of the people counted used the descending stairs, including 22 obviously overweight-obese people. A very small proportion of adults used the stairs in our exemplary sample (every eleventh chose the stairs for ascent and every fourth chose the stairs for descent), which confirms the high development potential for promoting short repetitive bouts of non-exercise physical activity in everyday life - also for overweight-obese people. Internalize the mantra: Stairs are good friends and not enemies!

Abstract Dear Editor-in-Chief
Overweight and obesity are considered as the most important lifestyle-related diseases today such that they are known as the fifth leading causes of death worldwide according to the published statistics. Moreover, as previous studies have shown, low-grade chronic inflammation is among the symptoms of these diseases and plays a key role in the pathogenesis of various physical problems and chronic diseases, such as cancer, diabetes, metabolic syndrome, cardiovascular, and neurodegenerative diseases (Safaei et al., 2021).
Meanwhile, new evidence suggests that leucine-rich α 2-glycoprotein 1 (LRG1) proinflammatory factor, an important upstream signaling pathway of transforming growth factor_⁃β (TGF_⁃β), will cause several pathological processes (Zou et al., 2022). In other words, it can be stated that LRG1, alone or in combination with other known factors, is considered as a potential biomarker for inflammation and obesity. There is a positive relationship between high levels of LRG1 and obesity, while low levels of plasma LRG1 predict weight loss in surgery for obesity and metabolic diseases (Pek et al., 2018). Investigation of the importance and the relationship of this issue in a broad study on 2,058 patients with type 2 diabetes showed that higher plasma LRG1 levels in women than men have a significant relationship with several risk factors for cardiovascular disease, namely arterial stiffness, endothelial dysfunction, systolic blood pressure, obesity, kidney disease, and high-sensitivity C-reactive protein (Pek et al., 2018; Zou et al., 2022). A recent 8-year longitudinal study also found that pigment epithelial-derived factor and plasma LRG1 mediated the inverse relationship between skeletal muscle mass and chronic kidney disease progression in patients with type 2 diabetes (Low et al., 2021). In other words, there is a positive correlation between high LRG1 levels in blood serum and adipose stores and high levels of body-mass-index (BMI), visceral adipose tissue, and waist circumference of obese people. According to these results and laboratory observations, LRG1 has been assumed to increase fat accumulation via suppression of fatty acids catabolism and inducing lipid biosynthesis through sterol regulatory element-binding transcription factor 1 activation or may enable hyperglycemia by decreasing expression of insulin receptor substrates (IRS1 and IRS2) (He et al., 2021).
On the other hand, consistent with the findings of studies showing the high serum levels of LRG1, it is possible that LRG1 binds preferentially to liver cells. With this assumption, LRG1 is considered a new adipokine that can play a role in obesity conditions by regulating an almost unique cross-talk between adipose tissue and the liver. More broad research is required to know whether LRG1 also exerts metabolic functions in physiological circumstances or not. However, the results of a study on LRG1 knockout mice with a high-fat diet revealed weight loss, smaller fat cell size, and preservation of brown adipose tissue in this type of mice. In other words, an increase in LRG1 gene expression during the process of fat lipogenesis can play an important role in regulating energy homeostasis (He et al., 2021; MacCannell et al., 2021). However, changing lifestyle by performing regular physical activity and a balanced diet have been introduced as a useful solution to prevent obesity. In this regard, a recent study on the elderly with an average BMI of 34 ± 1 kg / m2 showed that exercise combined with diet resulted in an 8-10 % weight loss in these individuals, indicating the possibility that molecular changes in peroxisome proliferator-activated receptor γ (PPARγ) coactivator 1α (PGC-1α) pathway can help transport fat and oxidize it in the skeletal muscles of older and obese people and in some ways regulate insulin resistance (Mulya et al., 2017).
Previous research studies have referred to the key role of PGC-1α in regulating mitochondrial function and helping regulate cellular energy status by enabling cellular energy in conditions 
when the body needs energy, such as fasting, performing exercise activities, or inhibiting it when the body has enough energy available. However, the evidence obtained regarding the role of PGC-1α and its relationship with LRG1 gene expression in obesity therapy showed that LRG1 expression in white adipose tissue reduced in mice model of insulin - resistant type II diabetes and obesity following treatment with PPARγ agonists (Muise et al., 2008). Moreover, evidence regarding the positive effects of exercise activity and the role of PGC-1α showed that probably five proteins, including interleukin 15 (IL-15), fibronectin type III domain- containing protein 5 (FNDC5), vascular endothelial growth factor B (VEGF-B), LRG1, and tissue inhibitor of metalloproteinase 4 (TIMP4), secreted in skeletal muscles, increase following endurance exercise activity and contribute to longevity as well (Boström et al., 2012).
Considering the evidence presented, LRG1 seems to play a key role in the pathogenesis of obesity. However, more broad research is required to better understand its relationship with other transcription factors, vital signaling pathways in this process, as well as the important effect of type, intensity, and duration of exercise activity, and type of diet in regulating its expression and its regulatory role in cross-talk with other organs to prevent obesity (Yang et al., 2021). 

Abstract Puberty with interactive growth in tissues is a sensitive period in life that can be more affected by obesity. Also the increase of leptin and insulin resistant independent of obesity have been seen in puberty. The aim of our study was to investigate the role of puberty on changes in leptin, testosterone, and insulin resistance in sedentary obese boy with considering possible crosstalk between leptin and insulin resistance. 58 sedentary obese boys (14.10 + 1.37 years) participated in this study. Tanner stage scales were used to measure puberty by self-reporting. Initially anthropometric characteristics and then, fasting serum’s glucose, insulin, leptin and testosterone, were measured. With increasing mature from TS2 to TS5, the increasing of testosterone, body mass and lean body mass and the reduction of body fat percentage were significantly (p≤0.05). but the changes in leptin and HOMA-IR were not significant. However, the decreased leptin after adjusting for BMI between TS3 and TS4 were significant (p≤0.05). During puberty, rapid growth in muscle tissue were associated with decreased body fat percent, serum leptin and insulin resistance. Among the possible reasons is a 15-fold increase in serum testosterone from TS2 to TS5. These changes reflect the cross talk between muscle and adipose tissue by hormonal mediators.