Journal of Exercise & Organ Cross Talk

Abstract Steatosis is the most important cause for chronic liver disease, from simple steatosis to advanced stages such as liver fibrosis and cirrhosis and liver cancer. In this study, the effect of MICT and probiotic consumption on IL15 gene expression in animal model of non-alcoholic steatosis was examined. This study is an experimental laboratory study. Thirty-two male wistar rats were divided into 4 groups of 8 in the healthy (normal diet), steatosis, steatosis + probiotic, steatosis + probiotic +MICT groups and tested for 8 weeks. The exercise protocol was as follows: in the first week from 10 minutes of running at a speed of 18 meters per minute to the eighth week with 60 minutes of running at a speed of 28 meters per minute. Consumption of probiotics; Relevant groups received 109 CFU / ml of Lactobacillus rhamnosus GG by gavage daily for 5 weeks and 5 days a week. Statistical calculation of this study was performed using SPSS 25 software. Probiotic consumption and moderate-intensity continuous training significantly increased IL-15 (p =0.000) and significantly decreased TG (p =0.000) in the non-alcoholic steatosis animal model. It seems moderate-intensity continuous training with probiotic consumption can improve the liver function of non-alcoholic fatty liver patients.

Abstract The purpose of this study was to investigate and compare the effect of eight weeks of continuous and interval training on PGC-1α and FNDC5 gene expression in the gastrocnemius muscle of male Wistar rats. 30 eight-week-old rats with an average weight of 192 ± 10 were randomly divided into 3 groups (n=10): control group (Ctrl), interval endurance training group (IET) and continuous endurance training group (CET). The exercise groups participated in 8 weeks of continuous or interval training program (5 days per week). 24 hours after the last training session, all the rats were anesthetized and their gastrocnemius muscles were collected and transferred to the laboratory to measure the mRNA levels of PGC-1α and FNDC5 genes by Real Time-PCR method. The results showed that the expression level of FNDC5 in the gastrocnemius muscle was significantly higher in the interval and continuous endurance training groups than in the control group. Also, the expression of this gene was higher in the interval group than in the continuous group. It was also found that the expression of PGC-1α gene was significantly increased in both training groups compared to the control group. Also, the expression of this gene increased significantly in the interval training group compared to the continuous. It seems that interval endurance training has a greater effect on the expression of PGC-1α and FNDC5 factors in the gastrocnemius muscle.

Abstract The purpose of this study was to determining the range of aerobic exercise on a treadmill for male Wistar rats at different ages. Twelve male Wistar rats were divide in three groups of immature, adults, and old (n= 4 in each). At first session, the rats began to run at a rate of 2 m/min to perform the fatigue test, and the treadmill speed was increased by 2 m/min every 2 minutes. This process of acceleration continued until the rats were no longer able to continue moving on the treadmill and became exhausted. Then, blood lactate of each subject measured immediately and their maximum speed was recorded. After 48 hours of recovery, animal performed maximum recorded speed on a treadmill in three 10-minute steps of 25%, 50% and 75%, respectively. Immediately after each percent blood lactate were measured and recorded. Immature rats at an average speed of 18 m/min were reached to their maximum speed with an average lactate concentration of 8±1.8 mmol/l. Adults rats at an average speed of 36 m/min were reached to their maximum speed with an average lactate concentration of 6.8±0.4 mmol/l. The old rats reached their maximum velocity with an average of 30 m/min with an average lactate concentration of 6.95±0.9 mmol/l. Therefore, it recommended that aerobic exercise in untrained rats start at a light speed, i.e. 25% of their maximum speed, which is lower than the lactate threshold, and gradually continue up to 50% of their maximum speed.

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 Like other cells in the body, nerve cells need many proteins and substances to maintain homeostasis. As we know, the transcription and translation of proteins and necessary cellular substances occurs in the cell nucleus. The nucleus of nerve cell is located in the cell body. Another part of the nerve cell is “Axon”, which has a long structure. Even in some nerve cells axon’s length reaches up to 1000 mm. On the other hand, all parts of the neuron need substances and proteins synthesized in nucleus locating in the cell body. Therefore, a mechanism is necessary to express the movement of materials from nucleus along the axon. The movement of materials along the axon is called ‘Axoplasmic Transport’. It seems that disturbances in axoplasmic transport can cause various neuronal problems. The purpose of this study is to investigate the mechanism of axoplasmic transport and its types; moreover, the possible effect of exercise on this transition will be discussed.

Abstract Dear Editor-in-Chief
Diabesity is a modern epidemic challenge associated with metabolic disorder and chronic inflammation (Ng et al., 2021). Diabesity is reported to cause several complications in the musculoskeletal system such as sarcopenia and osteoporosis (Collins et al., 2018). Evidence suggests that obesity and diabetes negatively affect musculoskeletal system which is in favor of increasing sarcopenia and osteoporosis (Barazzoni et al., 2018; Trierweiler et al., 2018). Sarcopenic obesity (SO) is a multifactorial condition ultimately leading to body composition changes (muscle mass decrease and fat mass increase) (Wang et al., 2020) while osteoporosis is a condition in which bone density gradually decreases, increasing bone fracture risk. Diabetes has been strongly associated with an increased risk of osteoporosis-associated fractures (Romero-Díaz et al.,  2021).
Hormonal changes are suggested as one of the contributing factors involved in the pathogenesis of diabesity (Wang et al., 2020). Both muscles and bones are recognized as endocrine organs secreting hormones involved in regulating metabolic and inflammatory pathways. There are numerous indications that muscle secretome contains osteoinducer and osteoinhibitor myokines; it also seems likely that bone cells secrete myoinducer and myoinhibitor osteokines (Trajanoska et al.,  2019). 
Meanwhile, irisin and meteorin-like hormone (Metrnl) are signaling proteins that have opened a new window at the diabetes research. Scientists from the Dasman diabetes institute in Kuwait in collaboration with scientists from other departments of surgery, pharmacology and toxicology at Kuwait university have been investigating Irisin and Metrnl involvements in obesity and type 2 diabetes (T2D) (Jamal et al., 2020).  As Irisin and Metrnl are discovered in the last decade, they are relatively new to scientific research. These proteins are signaling molecules produced by muscle and fat tissues in response to exercise and exposure to cold temperatures. These proteins signal mitochondria to generate energy which elevates energy expenditure and ultimately promotes weight loss (Jamal et al., 2020). This makes Irisin and Metrnl promising targets for obesity and T2D. Interestingly, researchers from Dasman diabetes institute recently discovered that these molecules are already elevated in people with obesity and T2D (AlKhairi et al., 2019). High levels of Irisin and Metrnl can be a sign that the body is attempting to restore its normal functioning. In rats undergoing a weight loss surgery (sleeve gastrectomy), the research team found increases in Irisin and Metrnl levels correlated with improvement in metabolic health (Jamal et al., 2020). This increase was also beneficial in boosting heat production as reflected by higher expression of the thermal protein UCP-1 in mitochondria. Separate experiments revealed how Irisin and Metrnl interact with muscle and the bone (Cherian et al., 2021). Results show a strong association between Irisin and Metrnl and the bone markers osteoactivin and osteoprotegerin which are involved in bone formation (Cherian et al., 2021). This molecular crosstalk might play a role in bone and muscle complications associated with T2D and obesity. More research is needed to understand the interaction between these various markers. Mapping these relationships could lead to new treatments counteracting the effects of T2D and obesity. 

Abstract Dear Editor-in-Chief
In recent years, exercise has been called an ‘amazing’ medicine and a ‘miracle’ cure. Scientific research shows that regular exercise is effective in preventing and treating many common diseases, including type 2 diabetes, dementia, depression, heart disease, some cancers, and other common diseases (Fang et al., 2022). In fact, exercise in a specific dose and formula is prescribed for each patient who is diagnosed with the disease. The prescription should be very clear in terms of modality, intensity, frequency, and duration.
In this regard, the American College of Sports Medicine (ACSM) has launched the "Exercise is Medicine" project to recognize the myriad health benefits of exercise. These include reducing the incidence of a number of different cancers, lowering the risk of excessive weight gain (along with related health problems as well as diabetes), and improving cardiovascular health (as well as reducing the risk of high blood pressure in addition to heart stroke) (Ghardashi-Afousi et al., 2018).
The acute effect of exercise has been shown to lead to a transient decrease in triglyceride levels, an increase in HDL cholesterol levels, a decrease in blood pressure, a decrease in insulin resistance, and an improvement in glucose control. Regular exercise increases blood flow and oxygen to the brain which improves memory and mental function. It also increases the production of a number of hormones that stimulate the growth of brain cells (Ueno-Pardi et al., 2022).
In addition, some literature describes exercise even better than medicine. For example, a review of more than 300 randomized controlled trials found that exercise was as effective as drugs at risk for heart disease and diabetes, and more effective than post-stroke rehabilitation drugs (Naci & Ioannidis, 2013).
It has previously been suggested that vaccinating children with exercise can control the obesity epidemic in them. Recently, in the coronavirus outbreak, exercise has been referred to as a vaccine or vaccine adjuvant (Naci & Ioannidis, 2013). A recent study in the British Journal of Sports Medicine (BJSM) suggests that routine activities may protect people with COVID-19 from serious illness.
Evidence suggests that exercise and obesity are involved in the pathogenesis of COVID-19 disease and vaccine efficacy. Regular exercise has been shown to exert immune regulatory effects, control viral gateway, modulate inflammation, stimulate NO production pathways, and control oxidative stress. Adaptation to ordinary exercise seems to affect immune function, particularly innate and adaptive immunity, and ameliorate humoral immunity with enhanced vaccination responses. Exercise may at least partially reduce the detrimental effect of SARS-CoV-2 binding to the ECA2 receptor. Exercise training can activate anti-inflammatory signaling pathways (Shirvani & Rostamkhani, 2020). Today, COVID-19 vaccination has shown that individuals who exercise continuously and regularly may develop higher antibody titers to the SARS-CoV-2 strain contained in the vaccine compared to individuals who do not exercise (Hallam et al., 2022).
On the other hand, understanding how obesity and adiposity affect immunity and more specifically the production and function of antibodies is of great importance (Malavazos et al., 2020). Numerous studies have shown the effect of obesity on antibody properties. For example, adaptive immune responses to influenza virus are impaired during obesity, innate and adaptive immune responses to influenza are delayed in obese patients, and obesity was suggested to decline influenza antibody titers following influenza vaccination and reduce vaccine efficacy with poor vaccine immunization. In the same manner, lower COVID-19 mRNA vaccine-induced antibody titers have been related to central obesity and severe acute respiratory syndrome (Ghanemi et al., 2021).     
In general, recent research on the Covid-19 epidemic has shown that exercise is not only a wonderful medicine in the prevention and treatment of many diseases, but also regular exercise can act as an adjunct vaccine. Therefore, prescribing exercise will always help promote community health and is completely in line with the P4 medicine approach (predictive, preventative, personalized, and participatory).