Effects of Exercise on ACE2

Sex and diet, but not exercise, alter cardiovascular ACE2 and TMPRSS2 mRNA levels in aortic banded swine

SARS-COV-2, or COVID-19, is a respiratory virus that enters tissues via the angiotensin-converting enzyme 2 (ACE2) receptor and is primed and activated by transmembrane protease, serine 2 (TMPRSS2). An interesting dichotomy exists regarding the preventative/therapeutic effects of exercise on COVID-19 infection and severity. Although exercise training has been shown to increase ACE2 receptor levels (increasing susceptibility to COVID-19 infection), it also lowers cardiovascular risk factors, systemic inflammation, and preserves normal renin-angiotensin system axis equilibrium, which is considered to outweigh any enhanced risk of infection by decreasing disease severity. The goal of this study was to determine the effects of chronic exercise training, sex, and Western diet on ACE2 and TMPRSS2 mRNA levels in preclinical swine models of heart failure. We hypothesized chronic exercise training and male sex would increase ACE2 and TMPRSS2 mRNA levels. A retrospective analysis was conducted in previously completed studies including: 1) sedentary and exercise-trained aortic banded male, intact Yucatan mini-swine (n = 6 or 7/group); 2) ovariectomized and/or aortic banded female, intact Yucatan mini-swine (n = 5-8/group); and 3) lean control or Western diet-fed aortic banded female, intact Ossabaw swine (n = 4 or 5/group). Left ventricle, right ventricle, and coronary vascular tissue were evaluated using qRT-PCR. A multivariable regression analysis was used to determine differences between exercise training, sex, and Western diet. Chronic exercise training did not alter ACE2 or TMPRSS2 level regardless of intensity. ACE2 mRNA was altered in a tissue-specific manner due to sex and Western diet. TMPRSS2 mRNA was altered in a tissue-dependent manner due to sex, Western diet, and pig species. These results highlight differences in ACE2 and TMPRSS2 mRNA regulation in an experimental setting of preclinical heart failure that may provide insight into the risk of cardiovascular complications of SARS-COV-2 infection.NEW & NOTEWORTHY This retrospective analysis evaluated the impact of exercise, sex, and diet on ACE2 and TMPRSS2 mRNA levels in preclinical swine heart failure models. Unlike normal exercise intensities, exercise training of an intensity tolerable to a patient with heart failure had no influence on ACE2 or TMPRSS2 mRNA. In a tissue-specific manner, ACE2 mRNA levels were altered due to sex and Western diet, whereas TMPRSS2 mRNA levels were sensitive to sex, Western diet, and pig species.

COVID-19 and aerobic exercise: possible role of angiotensin converting enzyme 2

The emergence and circulation of a novel coronavirus (2019-nCoV)—Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)—set off a global health crisis. SARS-CoV-2 spreads faster than its two ancestors, SARS-CoV and MERS-CoV. Several modes of transmission have been identified: via respiratory droplets, contact with infected people or contaminated surfaces, and potentially, bioaerosols. Various countries have taken preventive measures that may include partial or total lockdowns lasting weeks. The physical inactivity associated with lockdowns may promote cardiometabolic or other diseases, while physical activity may play a critical role in preventing them. Here we develop the hypothesis of the involvement of aerosols in the contamination process, the role of angiotensin converting enzyme 2 (ACE2), the potential benefits and harm of physical activity during lockdowns, and we suggest directions for future research.

The role of physical activity in the clinical outcomes of people diagnosed with Covid-19: A systematic review

Objective

This review aimed to compile the evidence on PA and clinical outcomes of people receiving a positive diagnosis of covid-19.

Design

Systematic review.

Methods

The search was performed in five databases: EMBASE, MEDLINE via PubMed portal, Scopus, SPORTDiscus via EBSCO platform, and Web of Science. In addition, the "gray" literature was searched through Google Scholar and medRxiv published between January 2020 and July 2022. Studies were assessed for risk of bias, with the extraction of relevant data. Our search revealed a total of 10,028 studies.

Results

After applying the eligibility criteria 32 studies were included. Thirty-one studies were at low to moderate risk of bias. Physically active individuals, who were diagnosed with covid-19, presented attenuation of clinical outcomes, such as decreased risk of hospitalization, recovery time, number of symptoms, severity, and ICU and death when compared to individuals with low levels of PA or classified as sedentary.

Conclusions

Physically active individuals when diagnosed with covid-19 may have decreased risk of several clinical outcomes related to covid-19, including but not limited to hospitalization and number of symptoms. Public health authorities should develop strategies and initiatives that promote safe PA environments to improve the clinical prognosis of people diagnosed with covid-19.

Study registration

Open Science Framework (OSF), DOI registry 10.17605/OSF.IO/PV6NF. It can be consulted through the access link: https://doi.org/10.17605/OSF.IO/PV6NF, October 07, 2021.

Physical activity and the risk of SARS-CoV-2 infection, severe COVID-19 illness and COVID-19 related mortality in South Korea: a nationwide cohort study

PURPOSE

To determine the potential associations between physical activity and risk of SARS-CoV-2 infection, severe illness from COVID-19 and COVID-19 related death using a nationwide cohort from South Korea.

METHODS

Data regarding 212 768 Korean adults (age ≥20 years), who tested for SARS-CoV-2, from 1 January 2020 to 30 May 2020, were obtained from the National Health Insurance Service of South Korea and further linked with the national general health examination from 1 January 2018 to 31 December 2019 to assess physical activity levels. SARS-CoV-2 positivity, severe COVID-19 illness and COVID-19 related death were the main outcomes. The observation period was between 1 January 2020 and 31 July 2020.

RESULTS

Out of 76 395 participants who completed the general health examination and were tested for SARS-CoV-2, 2295 (3.0%) were positive for SARS-CoV-2, 446 (0.58%) had severe illness from COVID-19 and 45 (0.059%) died from COVID-19. Adults who engaged in both aerobic and muscle strengthening activities according to the 2018 physical activity guidelines had a lower risk of SARS-CoV-2 infection (2.6% vs 3.1%; adjusted relative risk (aRR), 0.85; 95% CI 0.72 to 0.96), severe COVID-19 illness (0.35% vs 0.66%; aRR 0.42; 95% CI 0.19 to 0.91) and COVID-19 related death (0.02% vs 0.08%; aRR 0.24; 95% CI 0.05 to 0.99) than those who engaged in insufficient aerobic and muscle strengthening activities. Furthermore, the recommended range of metabolic equivalent task (MET; 500-1000 MET min/week) was associated with the maximum beneficial effect size for reduced risk of SARS-CoV-2 infection (aRR 0.78; 95% CI 0.66 to 0.92), severe COVID-19 illness (aRR 0.62; 95% CI 0.43 to 0.90) and COVID-19 related death (aRR 0.17; 95% CI 0.07 to 0.98). Similar patterns of association were observed in different sensitivity analyses.

CONCLUSION

Adults who engaged in the recommended levels of physical activity were associated with a decreased likelihood of SARS-CoV-2 infection, severe COVID-19 illness and COVID-19 related death. Our findings suggest that engaging in physical activity has substantial public health value and demonstrates potential benefits to combat COVID-19.

Intrinsic Exercise Capacity Affects Glycine and Angiotensin-Converting Enzyme 2 (ACE2) Levels in Sedentary and Exercise Trained Rats

Angiotensin-converting enzyme 2 (ACE2) has been identified as the cellular entry receptor for the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). High ACE2 tissue expression and low glycine levels were suggested to increase susceptibility for SARS-CoV-2 infection and increasing circulating ACE2 has been proposed as one possible strategy to combat COVID-19. In humans, aerobic physical exercise induces an increase in plasma ACE2 in some individuals. However, it is not clear whether glycine and ACE2 levels depend on intrinsic exercise capacity or on exercise training. We used rats selectively bred for high intrinsic exercise capacity (HCR) or low exercise capacity (LCR) and tested the influence of this genetic predetermination and/or aerobic exercise on metabolites, ACE2 tissue expression and circulating ACE 2. ACE2 expression was measured in different tissues in the sedentary animals and again after 4 weeks of high-intensity aerobic exercise in both LCRs and HCRs. Sedentary HCRs exhibited significantly higher circulating ACE2 concentrations compared to LCRs, but a lower expression of ACE2 in all investigated tissues except for adipose tissue. Body weight was negatively correlated with serum ACE2 and positively correlated with ACE2 expression in the heart. Aerobic exercise caused a significant decrease in ACE2 expression in the lung, heart, muscle, and kidney both in LCRs and HCRs. Our results suggest that ACE2 expression, circulating ACE2 and glycine serum concentration are related to aerobic intrinsic exercise capacity and can be influenced with exercise. These results may support the hypothesis that physically fit individuals have a lower susceptibility for COVID-19 infection.

Combined Effects of Exercise Training and Nutritional Supplementation in Cancer Patients in the Context of the COVID-19: A Perspective Study

The 2019 coronavirus (COVID-19) epidemic, has caused unprecedented global social and economic impacts and many deaths. Many risk factors have been identified in the progression of COVID-19 to severe and critical stages, and it is shown that the coronavirus appears more severely in people with cancer. Pro-inflammatory status and weakened immune system due to cancer-related treatments can be determinants in the immune system’s response to the coronavirus in these patients. Higher physical activity levels are associated with lower hospitalization rates and mortality in COVID-19. Also, regular exercise training can improve immune system responses, modulate inflammatory responses, and improve psychological parameters in cancer patients. The interactive effects of nutritional supplements on immune responses and anti-inflammatory status have been shown in some studies. The purpose of this perspective article was to investigate the interaction between dietary supplementation and regular physical exercise in controlling risk factors associated with coronavirus in cancer patients. In addition to appropriate dietary habits, some nutritional supplements, especially vitamin D, have been shown to improve the immune system’s response against COVID-19 and cancer. Using lifestyle strategies such as regular physical activity and intake of functional compounds as supplements can be effective in treatment outcomes, quality of life, and overall survival in cancer patients. We proposed that combining dietary supplements and exercise training in cancer patients can boost immune responses against COVID-19 and probably improve vaccine responses. Angiotensin (ANG)-(1-7) Mas receptor axis can probably activate following exercise training and vitamin D combination. And can prevent pulmonary injury, hematological alterations, and hyperinflammatory state in COVID-19.

Role of Exercise Intensity on Th1/Th2 Immune Modulations During the COVID-19 Pandemic

The COVID-19 pandemic has led to several pioneering scientific discoveries resulting in no effective solutions with the exception of vaccination. Moderate exercise is a significant non-pharmacological strategy, to reduce the infection-related burden of COVID-19, especially in patients who are obese, elderly, and with additional comorbidities. The imbalance of T helper type 1 (Th1) or T helper type 2 (Th2) cells has been well documented among populations who have suffered as a result of the COVID-19 pandemic, and who are at maximum risk of infection and mortality. Moderate and low intensity exercise can benefit persons at risk from the disease and survivors by favorable modulation in Th1/Th2 ratios. Moreover, in COVID-19 patients, mild to moderate intensity aerobic exercise also increases immune system function but high intensity aerobic exercise may have adverse effects on immune responses. In addition, sustained hypoxia in COVID-19 patients has been reported to cause organ failure and cell death. Hypoxic conditions have also been highlighted to be triggered in COVID-19-susceptible individuals and COVID-19 survivors. This suggests that hypoxia inducible factor (HIF 1α) might be an important focus for researchers investigating effective strategies to minimize the effects of the pandemic. Intermittent hypoxic preconditioning (IHP) is a method of exposing subjects to short bouts of moderate hypoxia interspersed with brief periods of normal oxygen concentrations (recovery). This methodology inhibits the production of pro-inflammatory factors, activates HIF-1α to activate target genes, and subsequently leads to a higher production of red blood cells and hemoglobin. This increases angiogenesis and increases oxygen transport capacity. These factors can help alleviate virus induced cardiopulmonary hemodynamic disorders and endothelial dysfunction. Therefore, during the COVID-19 pandemic we propose that populations should engage in low to moderate exercise individually designed, prescribed and specific, that utilizes IHP including pranayama (yoga), swimming and high-altitude hiking exercise. This would be beneficial in affecting HIF-1α to combat the disease and its severity. Therefore, the promotion of certain exercises should be considered by all sections of the population. However, exercise recommendations and prescription for COVID-19 patients should be structured to match individual levels of capability and adaptability.

High serum angiotensin-converting enzyme 2 activity as a biomarker of frailty in nursing home residents

Angiotensin-converting enzyme (ACE) and angiotensin-converting enzyme 2 (ACE2) are two of the main components of the renin-angiotensin system (RAS). Imbalanced RAS showing lower ACE2 has been associated with increased cardiovascular risk, muscular pathologies, sarcopenia, frailty, other age-related pathologies and a poorer health status. However, its role in aging remains unclear. Thus, the aim of this work was to analyze the serum enzymatic activity of ACE and ACE2, the ACE/ACE2 ratio and its association with anthropometric parameters, blood pressure, physical function, dependence and frailty in older people living in nursing homes. This study is a secondary analysis of baseline data from two randomized clinical trials in a population of 228 older individuals living in nursing homes (Spain). Serum ACE and ACE2 enzymatic activities were measured by fluorimetry. Variables linked to cardiovascular risk, physical function, dependence and frailty were measured using validated tests, indexes and scales. Association between ACE, ACE2 serum activities, the ACE/ACE2 ratio and the rest of the quantitative variables were assessed by Pearson's correlations and by partial correlations controlled by age and sex. The association between serum ACE and ACE2 activities, the ACE/ACE2 ratio and frailty scores was analyzed by generalized linear models with and without controlling for sex and age. Differences in enzymatic activities between sexes and between frail and non-frail individuals were analyzed using Student's t-test and general linear models to control analysis by age and sex. We found that higher serum ACE2 activity was associated with a higher body mass index, worse physical function, greater dependence and increased frailty. This association is consistent with the elevation of circulating ACE2 in certain pathological conditions and in line with RAS deregulation in muscular dystrophies. Serum ACE2 activity, in combination with other molecules, could be proposed as a biomarker of poor physical function, higher dependence and frailty.

Moderate exercise may prevent the development of severe forms of COVID-19, whereas high-intensity exercise may result in the opposite

Sedentary lifestyle increases the risk of hospitalization for COVID-19 independently of other factors. There is enough statistics to show that exercise prevents severe forms of COVID-19, but current recommendations do not set an upper limit for exercise intensity. The hypothesis presented in the paper states that intense exercise, through blood hypoxia, increases the expression of transmembrane angiotensin-converting enzyme 2 (tACE2) in the vascular endothelium, increasing the risk of developing serious forms of disease, especially in the untrained. On the other hand, moderate-intensity exercise increases the blood concentration of soluble angiotensin-converting enzyme 2 (ACE2) which has a protective role for SARS-CoV-2 infection and may prevent complications. The importance of this hypothesis consists in the revision of COVID-19 prophylaxis programs through physical exercises, with the possibility of administration of antioxidants to speed up the adaptation of vascular endothelial cells to exertion.