Journal of Exercise & Organ Cross Talk

Abstract Eccentric contractions predispose muscles to damage. Type II muscle fibers are more susceptible than type I, so it seems that contraction velocity interferes in mechanical stress and thus muscle damage. The purpose of this study was to investigate the effect of contraction velocity of acute dominant knee extensor eccentric exercise-induced muscle damage (EIMD) on running economy and metabolic responses in trained young females. Twenty-one trained young females were randomly assigned into two groups: high-velocity contraction eccentric exercise (240°s-1) and low-velocity (60°s-1). To induce muscle damage subjects, in high and low-velocity groups performed 20 and 5 sets of 15 repetitions, respectively, with a load equal to 150٪ of the maximal voluntary isometric contraction (MVIC) torque of knee extensors with a dominant limb. Then; MVIC of knee extensors was recorded before, one and 48 h after EIMD, and running economy (submaximal Steady-state vo2), and metabolic responses were recorded at 60, 70, and 80% of pre-determined vVO2max, 24 h before and 48 h after EIMD. Both exercise bouts resulted in significant changes in MVIC of knee extensor (p<0.05) with no significant difference between the two groups. No significant difference was found in running economy and metabolic responses in three different intensities following both exercise conditions between the two groups. Results of the analysis showed that a four-fold difference in contraction velocity of eccentric exercise-induced muscle damage was not sufficient to induce a difference in muscle damage, running economy, and metabolic responses when the knee extensor muscle tension duration was equalized.

Abstract Intense exercise training is associated with Lung inflammation. Fasl protein on the cell surface is responsible for the initiation of the inflammatory response that finally leads to cell death at the site of inflammation, and can be interpreted as Fasl induced apoptosis. Therefore, the aim of this study was to investigate the effects of increasing and intense interval exercise training on Fasl levels of mature rat lungs. 30 rats within three weeks of birth with mean weight 68±9 g were randomly divided into three basic, control, and exercise groups. Increasing interval training for 6 sessions per week, each session 30 minutes at a speed of 15 to 70 meters per min was employed and Fasl levels were measured using the kitby Elisa method. The data were analyzed with two-way ANOVA and LSD test was done at p≤0.05 significant level. The results showed that Fasl protein levels in the interval training group compared to baseline group increased by 23.75 % and was significant (p≤0/05). However, although the amount of this protein in the interval training group compared to the control group was high, this value was not significant. In addition, Fasl protein levels in the control group compared to the baseline group increased by13.58 % and was significant (p≤0.05). The findings indicated that intense and prolonged exercise training causes damage of the respiratory tract, and in turn, leads to the increased levels of Fasl.

Abstract The present study was conducted to investigate the effect of six weeks of intermittent exercise and curcumin consumption on plasma Apo A and Apo B concentrations in male Wistar rats. 30 male Wistar rats were randomly divided into six groups (5 rats in each group): control, diabetic, healthy intermittent exercise, intermittent exercise diabetes, curcumin diabetes and curcumin exercise diabetes. Diabetes was induced by intraperitoneal injection of streptozotocin poison (50 mg/kg). Intermittent training consisted of 5-12 bouts of intense work (75 to 100% of maximum speed) of 60 seconds with active rest intervals of 75 seconds, six days a week for six weeks. Curcumin was fed to animals by gavage at a dose of 50 mg per kilogram of body weight. The results demonstrated that diabetes induction significantly decreased plasma Apo A concentration (p≤0.01) and increased plasma Apo B concentration (p≤0.01). Intermittent training caused a significant increase in Apo A and a significant decrease in Apo B plasma in diabetic rats. Also, it was found that six weeks of curcumin consumption significantly increased the concentration of Apo A in plasma and decreased the concentration of Apo B and the ratio of Apo B to Apo A (p≤0.01). At end, the results of the present study showed that intermittent exercise, curcumin and the combination of two interventions improve the disorders caused by diabetes in apolipoproteins.

Abstract Fat mass and obesity-associated gene (FTO) is directly associated with increased risk of obesity and type 2 diabetes mellitus (T2DM). The purpose of current study was to investigate the effect of 12 weeks of resistance training (RT) on FTO expression in subcutaneous adipose tissue, glucose, and insulin levels in T2DM rats. Sixteen males Wistar rats (220±10 gr) with T2DM induced by streptozotocin-nicotinamide injection were randomly assigned into resistance training (RT; n=8) and control (Con; n=8) groups. RT was performed for 12 weeks, 5 days per week. FTO expression in subcutaneous adipose tissue, fasting blood glucose (FBS), insulin and insulin resistance (HOMA-IR) were measured 48 hours after the last exercise training session.   After the exercise training intervention, the FTO expression (p=0.004) and FBS (p=0.001) were significantly lower in the RT compared to the Con group while the insulin in the RT was significantly higher than that in the Con group (p=0.001). There was no significant difference in the insulin resistance between the two groups (p˃0.05). According to findings, it seems that RT can decrease FBS and FTO expression in subcutaneous adipose tissue of T2DM rats. Improved blood glucose in diabetic rats might be partially attributed to reduced FTO expression in response to RT.   

Abstract The present study was conducted to investigate the effect of six weeks of intermittent exercise and curcumin consumption on the lipid profile of diabetic male rats. In an experimental trial, 30 male Wistar rats were randomly divided into six groups (5 rats in each group): control, diabetic, healthy intermittent exercise, intermittent exercise +diabetes, curcumin +diabetes and curcumin+ exercise +diabetes. Diabetes was induced by intraperitoneal injection of streptozotocin poison (50 mg/kg). Intermittent training consisted of 5-12 bouts of intense work (75 to 100% of maximum speed) of 60 seconds with active rest intervals of 75 seconds, six days a week for six weeks. Curcumin was fed to animals by gavage at a dose of 50 mg per kilogram of body weight. After six weeks, unconscious animals and blood samples were collected from their hearts. The data were analyzed using ANOVA statistical test and Bonferroni post hoc test. Induction of diabetes caused an increase in cholesterol, TG and LDL levels (P=0.01). Intermittent training and curcumin, each alone, caused them to decrease (P=0.01). In addition, diabetes decreased HDL while intermittent exercise increased it, but curcumin supplementation did not have a significant effect. The effect of combining interval training with curcumin supplement was significant only for TG and did not have a significant effect on other data. Exercise training and curcumin can have an anti-inflammatory effect with reducing lipid profile and increasing HDL in diabetic animal.

Abstract High-intensity exercise training is one of the effective strategies to improve the performance of athletes to achieve excellent physical fitness. In the meantime, a look at the history of sports immunology reveals the idea of window theory, which has been of great concern. According to the history of exercise immunology, high-intensity exercise training can suppress the immune system leading to respiratory infections. It has recently been shown that high-intensity exercise training has no effect on suppressing the immune system. In this review, a new perspective on the immune system and high-intensity exercise training was presented to readers. Moreover, a new look at the history of high-intensity exercise training and the immune system and recent review studies was provided and some suggestions are offered.

Abstract Omicron, a new type of SARS-CoV-2 was first reported by South Africa to the World Health Organization (WHO) on November 24, 2021. Two days after Africa was reported to the World Health Organization, the Omicron was identified as a global threat. Omicron has many genetic mutations, the potential effects of which are more dangerous than other SARS-CoV-2 genetic mutations. With the increase in vaccination in the world, the amount of physical activity to improve the functioning of the immune system decreased. Relying on vaccines alone cannot guarantee an improvement in the functioning of the immune system and the people of the world, given the lack of knowledge about the prevalence of omicron and its potential dangers, should look for ways to boost the immune system. In this study, we highlight the importance of increasing physical activity at the time of omicron outbreaks, along with the proposed protocols.

Abstract Dear Editor-in-Chief
 
Based on recent studies, it is now clear that there is a muscle–brain endocrine loop that can be partly mediated by myokine signaling. There are also other metabolites as mediators which can affect circulating compounds (Rai & Demontis, 2016) and these include noncoding RNAs (Makarova et al., 2014), hormone-associated responses, as well as, muscular enzymes (Pedersen, 2019). Brain-Derived Neurotrophic Factor (BDNF) is considered to be a key role in helping to mediate the impacts of exercise on the hippocampus (Loprinzi & Frith, 2019). Studies conducted on laboratory rats showed an increase in BDNF mRNA and BDNF protein in the hippocampus of these animals when wheel running exercise was performed for 1 to 8 weeks (Adlard, Perreau, & Cotman, 2005; Farmer et al., 2004; Liu & Nusslock, 2018; Neeper, Góauctemez-Pinilla, Choi, & Cotman, 1995; Oliff, Berchtold, Isackson, & Cotman, 1998; Van Hoomissen, Chambliss, Holmes, & Dishman, 2003). In terms of cognitive functions, i.e. memory and learning, BDNF has also been demonstrated to be effective in the improvement of such functions (Vaynman, Ying, & Gomez‐Pinilla, 2004; Vaynman, Ying, & Gómez‐Pinilla, 2004).
Research on humans indicates that their brains can release BDNF while cycling (Rasmussen et al., 2009; Seifert et al., 2010), also in another study in healthy people as well as people with schizophrenia who had been training in aerobic exercise for three months, the level of BDNF increased in their hippocampus by 12% and 16%, respectively (Pajonk et al., 2010). As a growth factor for the hippocampus, BDNF plays a significant role in learning and improving cell survival (Wrann et al., 2013). Interestingly enough, research findings show that BDNF can also be expressed in skeletal muscle tissues during exercise in humans; nonetheless, it is not clear whether muscle-derived BDNF can get into the bloodstream from the muscle to create a direct interaction between muscle and brain (Matthews et al., 2009).
Some fascinating studies indicate that irisin and myokines cathepsin-B might cross the (BBB) blood-brain barrier, and consequently, BDNF levels may increase. In recent a study conducted by Moon et al. (Moon et al., 2016) a novel myokine, cathepsin B (CTSB) was identified. Other work also demonstrated that exercise can increase CTSB systemic level, therefore, BDNF expression will be promoted in the hippocampus and lead to the formation of nerve tissue as well. Running on a treadmill for four months increased CTSB plasma levels, as well as CTSB gene expression in humans, mice, and rhesus monkeys. In addition, it was indicated that CTSB could cross BBB in mice. In studies by Moon et al. (2016) on CTSB knockout mice, it was made clear that mice without CTSB refused to do voluntary exercise regarding hippocampal growth and cognitive development. It is not clear whether myokine CTSB can lead to cognitive function development in humans regarding exercise training or not (Moon et al., 2016; Suzuki, 2016).
The PGC-1α-dependent myokine irisin, which is famous for its browning impacts (Boström et al., 2012), can play a role in the intervention of the brain’s physical activity (Wrann et al., 2013). An excessive expression of irisin in the primary cortical neurons can cause a higher BDNF expression, while FNDC5 knockdown mediated by RNAi can cause a lower BDNF expression. Furthermore, irisin delivery to the mice’s liver by adenoviral vectors will raise the systemic irisin level, consequently resulting in a higher level of BDNF in the hippocampus. Whether doing exercise can increase irisin plasma concentration in humans (Albrecht et al., 2015; Wrann, 2015), and whether irisin is affected by a muscle–brain endocrine loop is a disputable issue.