Effects of Tai Chi exercise on blood pressure and plasma levels of nitric oxide, carbon monoxide and hydrogen sulfide in real-world patients with essential hypertension

Tai Chi training as a primary care plan for the prevention and management of hypertension: an opinion and positioning article

Hypertension is a prevalent chronic condition worldwide that can impact patients' quality of life. Oral antihypertensive drugs are widely used to manage high blood pressure, primarily by regulating the renin-angiotensin-aldosterone system. Nevertheless, limited efficacy and low compliance represent significant obstacles, arising primarily from dose, duration, and medication type restrictions. Furthermore, the prolonged use of antihypertensive medication may result in dependence and adverse effects, without any substantial improvement in achieving targeted blood pressure leves. As a result, research has focused on using exercise therapy to treat hypertension. Tai Chi, a widely-practiced Chinese health exercise, has evolved into a form of exercise therapy that might help alleviate the risk associated with hypertension. Therefore, this article aims to outline the role of Tai Chi in preventing and managing hypertension.

Efficacy of Tai Chi exercise in patients with hypertension: systematic review and meta-analysis

BACKGROUND

An estimated 1.28 billion adults aged 30-79 years worldwide have hypertension, most (two-thirds) living in low- and middle-income countries. Pharmachological approaches have side effect, prompting exploration of Non-pharmacological approaches, like Tai Chi. Although early evidence suggests a potential favourable benefit with Tai Chi, it remains unclear whether the method can significantly reduced SBP and DBP. We aimed to assess by a systematic review and meta-analysis the effectiveness of Tai Chi in alleviating SBP and DBP on hypertension patients.

METHODS

Our study adhered to the PRISMA method and was registered in PROSPERO under the code CRD42024496192. The search was carried out in the PubMed, Web of Science, Embase, and the Cochrane Library databases in December 2023. Five randomized controlled trials were included (a total of 568 patients). Risk of bias was employed to assess the quality of individual studies, and a random-effects model was utilized to examine the overall effect.

RESULTS

The results showed that Tai Chi, when compared to routine care, had a statistically significant impact on SBP ((MD = 5.49, 95 % CI: 3.44 to 7.54, p = 0.001), with a heterogeneity I2 = 54%. Tai Chi did not show a significant difference in terms of DBP when compared to standard care (MD =3.18, 95 % CI: 1.89 to -4.48, p = 0.31). The included trials exhibited small sample sizes, substantial heterogeneity.

CONCLUSIONS

Tai Chi effectively lowers SBP levels in hypertension patients, however, did not show a statistically significant difference on DBP.

Twenty-Four week Taichi training improves pulmonary diffusion capacity and glycemic control in patients with Type 2 diabetes mellitus

This study evaluated the effect of 24-week Taichi training and Taichi plus resistance band training on pulmonary diffusion capacity and glycemic control in patients with Type 2 diabetes mellitus (T2DM). Forty-eight patients with T2DM were randomly divided into three groups: Group A-Taichi training: practiced Taichi 60 min/day, 6 days/week for 24 weeks; Group B-Taichi plus resistance band training: practiced 60-min Taichi 4 days/week plus 60-min resistance band training 2 days/week for 24 weeks; and Group C-controls: maintaining their daily lifestyles. Stepwise multiple regression analysis was applied to predict diffusion capacity of the lungs for carbon monoxide (DLCO) by fasting blood glucose, insulin, glycosylated hemoglobin (HbA1c), tumour necrosis factor alpha (TNF-α), von Willebrand Factor (vWF), interleukin-6 (IL-6), intercellular adhesion molecule 1 (ICAM-1), endothelial nitric oxide synthase (eNOS), nitric oxide (NO), endothelin-1 (ET-1), vascular endothelial growth factor, and prostaglandin I-2. Taichi with or without resistance band training significantly improved DLCO, increased insulin sensitivity, eNOS and NO, and reduced fasting blood glucose, insulin, HbA1c, TNF-α, vWF, IL-6, ICAM-1, and ET-1. There was no change in any of these variables in the control group. DLCO was significantly predicted (R2 = 0.82) by insulin sensitivity (standard-β = 0.415, P<0.001), eNOS (standard-β = 0.128, P = 0.017), TNF-α (standard-β = -0.259, P = 0.001), vWF (standard-β = -0.201, P = 0.007), and IL-6 (standard-β = -0.175, P = 0.032) in patients with T2DM. The impact of insulin sensitivity was the most important predictor for the variation of DLCO based on the multiple regression modeling. This study demonstrates that 24-week Taichi training and Taichi plus resistance band training effectively improve pulmonary diffusion capacity and blood glycemic control in patients with T2DM. Variation of DLCO is explained by improved insulin sensitivity and endothelial function, and reduced inflammatory markers, including TNF-α, vWF, and IL-6.

Circulating Levels of Hydrogen Sulfide (H2S) in Patients with Age-Related Diseases: A Systematic Review and Meta-Analysis

Hydrogen sulfide (H₂S) is an endogenous gasotransmitter that promotes multiple biological effects in many organs and tissues. An imbalanced biosynthesis of H₂S has been observed in animal models of age-related pathological conditions. However, the results from human studies are inconsistent. We performed a systematic review with meta-analysis of studies searched in Medline, Embase, Scopus, and CENTRAL databases. We included observational studies on patients with age-related diseases showing levels of H₂S in blood, plasma, or serum. All the analyses were carried out with R software. 31 studies were included in the systematic review and 21 in the meta-analysis. The circulating levels of H₂S were significantly reduced in patients with progressive, chronic, and degenerative diseases compared with healthy people (standardized mean difference, SMD: -1.25; 95% confidence interval, CI: -1.98; -0.52). When we stratified results by type of disorder, we observed a significant reduction in circulating levels of H₂S in patients with vascular disease (e.g., hypertension) (SMD: -1.32; 95% CI: -2.43; -0.22) or kidney disease (SMD: -2.24; 95% CI: -4.40; -0.08) compared with the control group. These results could support the potential use of compounds targeting the "H₂S system" to slow down the progression of many diseases in the elderly.

Effects of the different Tai Chi exercise cycles on patients with essential hypertension: A systematic review and meta-analysis

Objective

The main treatment for essential hypertension at this stage is pharmacotherapy. Long-term pharmacotherapy is costly with some side effects. Tai Chi, a bright star in traditional Chinese arts, relaxes both mind and body and has been shown to relax blood vessels and lower blood pressure. This study aimed to systematically review the therapeutic effectiveness of the Tai Chi exercise cycle on blood pressure and cardiovascular risk factors of patients with essential hypertension.

Methods

Searching CNKI, VIP, CBM, PubMed, EBSCO, Embase, Cochrane Library, and Web of Science to collect randomized controlled trials about Tai Chi exercise in the treatment of patients with essential hypertension according to the inclusion and exclusion criteria. The search time ranged from the date of database construction to December 2022. The Cochrane risk-of-bias tool was used to evaluate the included trials. The meta-analysis was performed with RevMan5.3 and Stata12.0 software.

Results

According to the meta-analysis, compared with the controls, Tai Chi exercise with a cycle of more than 12 weeks may be better for the reduction of systolic blood pressure (SBP) [MD = -11.72, 95% CI (-15.52, -7.91)] and diastolic blood pressure (DBP) [MD = -4.68, 95% CI (-7.23, -2.12)], as well as increasing the content of nitric oxide (NO) [MD = 0.99, 95% CI (0.69, 1.28)]. The blood lipid metabolism ability may also be improved after more than 12 weeks of Tai Chi exercise, total cholesterol (TC) [SMD = -0.68, 95% CI (-0.89, -0.46), triglyceride (TG) [SMD = -0.84, 95% CI (-1.25, -0.43)], low-density lipoprotein cholesterol (LDL-C) [SMD = -1.58, 95% CI (-2.29, -0.86)]. However, the improvement of high-density lipoprotein cholesterol (HDL-C) [SMD = 0.54, 95% CI (0.28, 0.79)] was better with a less than 12 weeks exercise cycle. A subgroup analysis for exercise frequency and time showed that the exercise frequency should preferably be more than or equal to 5 times per week for patients with hypertension, and for patients with hypertension plus hyperlipidemia, the exercise frequency less than 5 times per week with exercise time less than 60 min each day may be more beneficial.

Conclusion

The meta-analysis indicated that a more than 12 weeks Tai Chi exercise cycle with less than 60 min each time and more than 5 times per week may be more beneficial in blood pressure reduction, NO level increasing and blood lipid metabolism improving in the comparison with the other exercise cycles. For patients with hypertension plus hyperlipidemia, exercise frequency of less than 5 times per week may be better.

Systematic Review Registration

[http://www.crd.york.ac.uk/prospero], identifier [CRD42022352035].

The Effect of Mind-Body Exercise on Blood Pressure in Middle-Aged and Elderly Patients with Hypertension: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Objectives. The effects and safety of mind-body exercise in improving blood pressure in middle-aged and elderly patients with hypertension were explored in this meta-analysis. Methods. A meta-analysis of studies from the China National Knowledge Infrastructure, Web of Science, PubMed, and Cochrane was performed to identify related experimental studies by screening out the randomized controlled trials from the time of respective database creation until January 22, 2021. In addition, first, we completed the research registration on the INPLASY platform on March 20, 2021 (registration number: INPLASY202130072) and, second, on the PROSPERO platform on December 28, 2021 (registration number: CRD42021289125). The data were analyzed using a random-effects model with the help of Stata 14.0 software. Results. A total of 2,277 patients from 30 studies were reflected in the present study. The results show that mind-body exercise can effectively improve systolic blood pressure [SMD = −0.994, 95% CI: −1.239∼−0.748, $P<0.01$ ] and diastolic blood pressure [SMD = −0.757, 95% CI: −1.009∼−0.505, $P<0.01$ ] in middle-aged and elderly patients with hypertension. Conclusion. The results of this meta-analysis show that mind-body exercise can effectively improve blood pressure in middle-aged and elderly patients with hypertension without adverse events.

The role of brain gaseous neurotransmitters in anxiety

Although anxiety is perhaps one of the most significant current medical and social problems, the neurochemical mechanistic background of this common condition remains to be fully understood. Multifunctional regulatory gasotransmitters are novel, atypical inorganic factors of the brain that are involved in the mechanisms of anxiety responses. Nitric oxide (NO) signaling shows ambiguous action in animal models of anxiety, while NO donors exert anxiogenic or anxiolytic effect depending on their chemical structure, dose, treatment schedule and gas release rapidity. The majority of NO synthase inhibitors act as a relatively potent axiolytic agents, while hydrogen sulfide (H₂S) and carbon monoxide (CO) delivered experimentally in the form of "slow" or "fast" releasing donors have recently been considered as anxiolytic neurotransmitters. In this comprehensive review we critically summarize the literature regarding the intriguing roles of NO, H₂S and CO in the neuromolecular mechanisms of anxiety in the context of their putative, yet promising therapeutic application. A possible mechanism of gasotransmitter action at the level of anxiety-related synaptic transmission is also presented. Brain gasesous neuromediators urgently require further wide ranging studies to clarify their potential value for the current neuropharmacology of anxiety disorders.

Tai Ji Quan as antihypertensive lifestyle therapy: A systematic review and meta-analysis

BACKGROUND

Professional health organizations are not currently recommending Tai Ji Quan alongside aerobic exercise to treat hypertension. We aimed to examine the efficacy of Tai Ji Quan as antihypertensive lifestyle therapy.

METHODS

Tai Ji Quan interventions published in English and Chinese were included when they involved healthy adults, reported pre- and post-intervention blood pressure (BP), and had a non-exercise/non-diet control group. We systematically searched 11 electronic databases for studies published through July 31, 2018, yielding 31 qualifying controlled trials. We (1) evaluated the risk of bias and methodological study quality, (2) performed meta-regression analyses following random-effects assumptions, and (3) generated additive models representing the largest possible clinically relevant BP reductions.

RESULTS

Participants (n = 3223) were middle-aged (56.6 ± 15.1 years of age, mean ± SD) adults with prehypertension (systolic BP (SBP) = 136.9 ± 15.2 mmHg, diastolic BP (DBP) = 83.4 ± 8.7 mmHg). Tai Ji Quan was practiced 4.0 ± 1.4 sessions/week for 54.0 ± 10.6 min/session for 22.3 ± 20.2 weeks. Overall, Tai Ji Quan elicited significant reductions in SBP (-11.3 mmHg, 95%CI: -14.6 to -8.0; d+ = -0.75) and DBP (-4.8 mmHg, 95%CI: -6.4 to -3.1; d+ = -0.53) vs. control (p < 0.001). Controlling for publication bias among samples with hypertension, Tai Ji Quan trials published in English elicited SBP reductions of 10.4 mmHg and DBP reductions of 4.0 mmHg, which was half the magnitude of trials published in Chinese (SBP reductions of 18.6 mmHg and DBP reductions of 8.8 mmHg).

CONCLUSION

Our results indicate that Tai Ji Quan is a viable antihypertensive lifestyle therapy that produces clinically meaningful BP reductions (i.e., 10.4 mmHg and 4.0 mmHg of SBP and DBP reductions, respectively) among individuals with hypertension. Such magnitude of BP reductions can lower the incidence of cardiovascular disease by up to 40%.

Effect of Tai Chi Combined with Mental Imagery on Cutaneous Microcirculatory Function and Blood Pressure in a Diabetic and Elderly Population

The purpose of this study was to investigate the effects of Tai Chi (TC) training combined with mental imagery (MI) on blood pressure and cutaneous microcirculatory function in individuals with diabetes and age-matched healthy subjects. All subjects participated in a one-hour Yang style TC exercise with MI twice per week for 8 weeks. An activities-specific balance confidence (ABC) measurement, a single-leg stance (SLS), a functional reach test (FRT), systolic and diastolic blood pressure, and skin blood flow were assessed. All functional outcomes were significantly improved in both groups, and systolic and diastolic blood pressures were lower in both groups after the TC training (p < 0.05), but there was no significant group effect. Skin blood flow decreased in the age-matched elderly group when heat and occlusion were applied (p < 0.05), but no difference was found in the diabetes group. Combining TC with MI showed an improvement in functional outcomes and blood pressure but cutaneous microcirculatory function did not improve. Combining TC intervention with MI theory showed an improvement in functional outcomes and blood pressure, which showed cardiovascular benefits not only in diabetes but in age-matched healthy subjects. However, cutaneous microcirculatory function was increased only in age-matched healthy subjects.

Irisin lowers blood pressure by activating the Nrf2 signaling pathway in the hypothalamic paraventricular nucleus of spontaneously hypertensive rats

Exercise training is one of the major non-pharmacological treatments for hypertension. However, the central mechanism by which exercise training attenuates the hypertensive responses remains unclear. Irisin is a muscle-secreted cytokine derived from fibronectin type III domain containing 5 (FNDC5) that will be released into the circulation during exercise. We hypothesized that irisin may play a role in the blood pressure regulation by exercise. To examine the hypothesis, our study investigated the effect of irisin on hypertension and its central mechanism. The study was performed in spontaneously hypertensive rats (SHRs) and normotensive Wistar-Kyoto rats. We found that intravenous injection of irisin effectively reduced blood pressure, plasma norepinephrine, paraventricular nucleus (PVN) levels of neuronal activation, oxidative stress and inflammation in SHRs. Moreover, irisin activated nuclear factor E2-related factor-2 (Nrf2) and restored the imbalance of neurotransmitters in the PVN. Our study also found PVN knockdown of Nrf2 abolished the protective effects of irisin on hypertension. These findings demonstrate irisin can improve hypertension via Nrf2-mediated antioxidant in the PVN.

A Review on the Nonpharmacological Therapy of Traditional Chinese Medicine with Antihypertensive Effects

Hypertension is a global health concern. Although the pharmacological treatment has obvious antihypertensive effects, there are still some limitations on management of hypertension by drug therapy alone. In recent years, the nonpharmacological therapy of traditional Chinese medicine (TCM) has gradually become an important mean to help the prevention and treatment of hypertension in some Eastern countries. In this review, the nonpharmacological TCM therapies, including acupuncture, tuina, Tai Chi, and auricular-plaster, are covered along with the mechanism.

Chronic aerobic exercise training alleviates myocardial fibrosis in aged rats through restoring bioavailability of hydrogen sulfide

Age-related fibrosis is attenuated by aerobic exercise; however, little is known concerning the underlying molecular mechanism. To address this question, aged rats were given moderate-intensity exercise for 12 weeks. After exercise in aged rats, hydrogen sulfide levels in plasma and heart increased 39.8% and 90.9%, respectively. Exercise upregulated expression of cystathionine γ-lyase and 3-mercaptopyruvate sulfurtransferase in heart of aged rats. Furthermore, aged rats were given moderate-intensity exercise for 12 weeks or treated with NaHS (intraperitoneal injection of 0.1 mL/kg per day of 0.28 mol/L NaHS). After exercise in aged rats, Masson-trichrome staining area decreased 34.8% and myocardial hydroxyproline levels decreased 29.6%. Exercise downregulated expression of collagen-I and α- smooth muscle actin in heart of aged rats. Exercise in aged rats reduced malondialdehyde levels in plasma and heart and 3-nitrotyrosine in heart. Exercise in aged rats reduced mRNA and protein expression of C/EBP homologous protein, glucose regulated protein 78, and X-box protein 1. Exercise also reduced mRNA and protein expression of interleukin 6 and monocyte chemotactic protein 1and suppressed activation of c-Jun N-terminal kinase in aging heart. Similar effects were demonstrated in aged rats treated with NaHS. Collectively, exercise restored bioavailability of hydrogen sulfide in the heart of aged rats, which partly explained the benefits of exercise against myocardial fibrosis of aged population.

Effectiveness of Tai Chi on Cardiac Autonomic Function and Symptomatology in Women With Fibromyalgia: A Randomized Controlled Trial

The present study examined the effects of a 12-week Tai Chi (TC) training regimen on heart rate variability (HRV), symptomatology, muscle fitness and body composition in women with fibromyalgia. Participants were randomly assigned to either a TC training group (n = 18) or a control group (n = 19). HRV, symptomatology, muscle fitness and body composition were measured before and after 12 weeks. There were significant decreases (p < 0.05) in sympathovagal balance (LnLF/LnHF), sympathetic tone (LnLF, nLF), pain, and fatigue, and significant increases (p < 0.05) in parasympathetic tone (LnHF, nHF), strength and flexibility following TC compared with no changes after control. The changes in LnLF and LnLF/LnHF were correlated with changes in pain. There were no significant changes in HR, sleep quality and body composition after TC or control. TC may be an effective therapeutic intervention for improving sympathovagal balance, pain, fatigue, strength and flexibility in women with fibromyalgia.

Effects of 12-week brisk walking training on exercise blood pressure in elderly patients with essential hypertension: a pilot study

BACKGROUND

Essential hypertension (EP) is characterized by blood pressure (BP) elevations, which often lead to target organ damage and cardiovascular illness. The following study investigates whether aerobic exercise programs with different intensities could reduce the magnitude of BP rise.

METHODS

Patients with essential hypertension were recruited from the Baoshan Community Health Service Center. A total of 46 patients were finally selected and randomly assigned into two groups: control group (CON) included patients who did not participate in exercise intervention training; treatment group (TRG) included patients who participated in 12-week brisk walking training (60-min of brisk walking, three times a week for a total of 12 weeks). 3-minute step tests of low and high intensity were conducted pre- and post-intervention. To compare the effects of exercise intervention, 23 subjects with normal blood pressure (NBP) who did not participate in 12-week brisk walking training, were recruited.

RESULTS

After 12 weeks of brisk walking, SBP of TRG during resting, low and high-intensity exercise was significantly reduced by 8.3mmHg, 15.6mmHg, and 22.6mmHg, respectively; while HR of TRG's during resting, low and high intensity was significantly reduced by 3.6beats/minute, 8.7beats/minute and 11.3beats/minute, respectively. Meanwhile, after 12 weeks of brisk walking, TRG's steps per day, [Formula: see text]o_2max, moderate physical activity time and physical activity energy expenditure significantly increased by 6000 steps, 2.4 ml/kg/m, 40 minutes and 113 kcal, respectively. At the same time, TRG's body fat rate and sedentary time significantly reduced by 2% and 60 minutes per day.

CONCLUSION

Brisk walking can reduce the magnitude of BP rise during exercise of different intensities and may be reduced the risk of acute cardiovascular incidents in elderly patients with essential hypertension.

ABBREVIATIONS

EP: Essential hypertension; BP: blood pressure; CON: control group; TRG: treatment group; NBP: normal blood pressure; PA: physical activity.

High-intensity interval training lowers blood pressure and improves apelin and NOx plasma levels in older treated hypertensive individuals

Hypertension is the major risk factor for cardiovascular diseases and is one of the primary causes of morbidity and mortality worldwide. Apelin levels and NO bioavailability are impaired in older hypertensive patients. Exercise is an effective intervention for treating hypertension. Our purpose was to evaluate the effect of high-intensity interval training on blood pressure, apelin, and NOx plasma levels in older treated hypertensive individuals. Thirty treated hypertensive subjects (61.70 ± 5.78 years, 17 males, 13 females) were randomly divided into 6 weeks of high-intensity interval training (n = 15) and control (n = 15). The exercise training was conducted for three 35-min sessions a week (1.5-min interval at 85-90% of heart rate reserve [HRR] and 2 min active phase at 50-55% of HRR). Assessment of plasma apelin, nitrite/nitrate (NOx), and endothelin-1 (ET-1) was performed before and after the intervention. At the end of the study, apelin, and NOx plasma levels increased significantly in the high-intensity interval training (HIIT) group (P = 0.021, P = 0.003, respectively). Conversely, ET-1 plasma levels significantly decreased in the training group after the intervention (P = 0.015). Moreover, there was a positive correlation between the change of plasma apelin and change of plasma NOx (r = 0. 771, P = 0.0008). In addition, there was a negative correlation between the change of plasma ET-1, change of plasma apelin (r = - 0.595, P = 0.019), and variation of NOx (r = - 0.572, P = 0.025). This study indicates that, by increasing of apelin and NOx plasma levels, HIIT may be effective in reducing blood pressure.

Efficacy of Tai Chi and qigong for the prevention of stroke and stroke risk factors: A systematic review with meta-analysis

BACKGROUND

This review aims to summarize the evidence of Tai Chi and qigong interventions for the primary prevention of stroke, including the effects on populations with major stroke risk factors.

METHODS

A systematic literature search was conducted on January 16, 2017 using the PubMed, Scopus, Cochrane Library, and CINAHL databases. Randomized controlled trials examining the efficacy of Tai Chi or qigong for stroke prevention and stroke risk factors were included. Risk of bias was assessed using the Cochrane Risk of Bias tool.

RESULTS

Twenty-one trials with n = 1604 patients with hypertension, hyperlipidaemia, diabetes, overweight or obesity, or metabolic syndrome were included. No trials were found that examined the effects of Tai Chi/qigong on stroke incidence. Meta-analyses revealed significant, but not robust, benefits of Tai Chi/qigong over no interventions for hypertension (systolic blood pressure: -15.55 mm Hg (95% CI: -21.16; -9.95); diastolic blood pressure: -10.66 mm Hg (95% CI: -14.90, -6.43); the homeostatic model assessment (HOMA) index (-2.86%; 95% CI: -5.35, -0.38) and fasting blood glucose (-9.6 mg/dL; 95% CI: -17.28, -1.91), and for the body mass index compared with exercise controls (-1.65 kg/m; 95% CI: -3.11, -0.20). Risk of bias was unclear or high for the majority of trials and domains, and heterogeneity between trials was high. Only 6 trials adequately reported safety. No recommendation for the use of Tai Chi/qigong for the prevention of stroke can be given.

CONCLUSION

Although Tai Chi and qigong show some potential more robust studies are required to provide conclusive evidence on the efficacy and safety of Tai Chi and qigong for reducing major stroke risk factors.

The Effect of Three Different Meditation Exercises on Hypertension: A Network Meta-Analysis

We aimed to use the pairwise and network meta-analysis to estimate the effects of different meditation exercises on the control of systolic blood pressure (SBP) and diastolic blood pressure (DBP). Randomized controlled trials (RCTs) were retrieved from PubMed and Embase up to June 2016, which are published in English and reported on meditation exercise for hypertensive patients. Risks of bias assessment of the included studies were assessed by Cochrane Collaboration Recommendations and network meta-analysis was performed by ADDIS. Mean difference (MD) and its 95% confidence interval (CI) were used as the effect size. A number of 19 RCTs were included in this study. Results of pairwise comparisons indicated that meditation exercise could significantly decrease the SBP and DBP, compared with other interventions (MD = −7.10, 95% CI: −10.82 to −3.39; MD = −4.02, 95% CI: −6.12 to −1.92). With good consistence and convergence, network meta-analysis showed that there were no significant differences between meditation and other interventions on SBP. For DBP, Qigong was significantly lower than “no intervention” (MD = −11.73, 95% CI: −19.85 to −3.69). Qigong may be the optimal exercise way in lowering SBP and DBP of hypertensive patients, but a detailed long-term clinical research should be needed in the future.

Cardiovascular effects of gasotransmitter donors

Gasotransmitters represent a subfamily of the endogenous gaseous signaling molecules that include nitric oxide (NO), carbon monoxide (CO), and hydrogen sulphide (H(2)S). These particular gases share many common features in their production and function, but they fulfill their physiological tasks in unique ways that differ from those of classical signaling molecules found in tissues and organs. These gasotransmitters may antagonize or potentiate each other's cellular effects at the level of their production, their downstream molecular targets and their direct interactions. All three gasotransmitters induce vasodilatation, inhibit apoptosis directly or by increasing the expression of anti-apoptotic genes, and activate antioxidants while inhibiting inflammatory actions. NO and CO may concomitantly participate in vasorelaxation, anti-inflammation and angiogenesis. NO and H(2)S collaborate in the regulation of vascular tone. Finally, H(2)S may upregulate the heme oxygenase/carbon monoxide (HO/CO) pathway during hypoxic conditions. All three gasotransmitters are produced by specific enzymes in different cell types that include cardiomyocytes, endothelial cells and smooth muscle cells. As translational research on gasotransmitters has exploded over the past years, drugs that alter the production/levels of the gasotransmitters themselves or modulate their signaling pathways are now being developed. This review is focused on the cardiovascular effects of NO, CO, and H(2)S. Moreover, their donors as drug targeting the cardiovascular system are briefly described.

Hypertension and Exercise Training: Evidence from Clinical Studies

Hypertension is a worldwide prevalent disease, mostly manifested as its primary ethiology, characterized by a chronic, multifactorial, asymptomatic, and usually incurable state. It is estimated that more than one billion of the world population is hypertensive. Also, hypertension is the main cause of the two most frequent causes of death worldwide: myocardial infarction and stroke. Due to the necessity of the cardiovascular system to manage chronically increased levels of blood pressure, hypertension causes severe alterations in multiple organs, as the heart, vessels, kidneys, eyes and brain, thus increasing the risk of health complications. The heart is the main target organ and suffers several adaptations to compensate the increased blood pressure levels; nevertheless, long-term adaptations without proper control are extremely harmful to cardiovascular health. On the other hand, hypertension is a modifiable risk factor and its adequate control is highly dependent on lifestyle. Pharmacological treatment is of great success when adherence is high. Several classes of antihypertensive drugs are prescribed and can effectively maintain blood pressure within acceptable levels. However, non-pharmacological methods, as diet and exercise training, can not only optimize the treatment but also prevent or postpone hypertension development as well as its complications, acting as important complements to the ideal control of elevated blood pressure, and bringing together benefits beyond blood pressure decrease, as a general health status improvement and increased quality of life. There is consistent evidence that regular exercise training promotes several benefits when properly prescribed and practised, acting as "medicine" for dozens of chronic diseases. The effects of exercise training in blood pressure levels and in its mechanisms of control are of clinical relevance and efficacy. This chapter will describe the classical and recent results on the beneficial effects of different modalities of exercise training in the cardiovascular system of human primary hypertension, focusing on the mechanisms influenced by exercise training which help to decrease blood pressure and improve the cardiovascular system.

Irisin Lowers Blood Pressure by Improvement of Endothelial Dysfunction via AMPK-Akt-eNOS-NO Pathway in the Spontaneously Hypertensive Rat

BACKGROUND

Exercise is a major nonpharmacological treatment for hypertension, but its underlying mechanisms are still not completely elucidated. Irisin, a polypeptide containing 112 amino acids, which is secreted mainly by skeletal muscle cells during exercise, exerts a protective role in metabolic diseases, such as diabetes mellitus and obesity. Because of the close relationship between irisin and metabolic diseases, we hypothesized that irisin may play a role in the regulation of blood pressure.

METHODS AND RESULTS

Blood pressures of male Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHRs) were monitored through the carotid artery. Our study found that acute intravenous injection of irisin reduced blood pressure in SHRs, but not WKY rats. Irisin, by itself, had no direct vasorelaxing effect in phenylephrine-preconstricted mesenteric arteries from SHRs. However, irisin augmented the acetylcholine-induced vasorelaxation in mesenteric arteries from SHRs that could be reversed by Nω-nitro-l-arginine-methyl ester (L-NAME; 100 μmol/L), indicating a role of nitric oxide (NO) in this action. Indeed, irisin increased NO production and phosphorylation of endothelial nirtic oxide synthase (eNOS) in endothelial cells. 5'-AMP-activated protein kinase (AMPK) was involved in the vasorelaxing effect of irisin because compound C (20 μmol/L), an AMPK inhibitor, blocked the irisin-mediated increase in phosphorylation of eNOS and protein kinase B (Akt) in endothelial cells and vasodilation in mesenteric arteries.

CONCLUSIONS

We conclude that acute administration of irisin lowers blood pressure of SHRs by amelioration of endothelial dysfunction of the mesenteric artery through the AMPK-Akt-eNOS-NO signaling pathway.

Physical exercise associated with NO production: signaling pathways and significance in health and disease

Here we review available data on nitric oxide (NO)-mediated signaling in skeletal muscle during physical exercise. Nitric oxide modulates skeletal myocyte function, hormone regulation, and local microcirculation. Nitric oxide underlies the therapeutic effects of physical activity whereas the pharmacological modulators of NO-mediated signaling are the promising therapeutic agents in different diseases. Nitric oxide production increases in skeletal muscle in response to physical activity. This molecule can alter energy supply in skeletal muscle through hormonal modulation. Mitochondria in skeletal muscle tissue are highly abundant and play a pivotal role in metabolism. Considering NO a plausible regulator of mitochondrial biogenesis that directly affects cellular respiration, we discuss the mechanisms of NO-induced mitochondrial biogenesis in the skeletal muscle cells. We also review available data on myokines, the molecules that are expressed and released by the muscle fibers and exert autocrine, paracrine and/or endocrine effects. The article suggests the presence of putative interplay between NO-mediated signaling and myokines in skeletal muscle. Data demonstrate an important role of NO in various diseases and suggest that physical training may improve health of patients with diabetes, chronic heart failure, and even degenerative muscle diseases. We conclude that NO-associated signaling represents a promising target for the treatment of various diseases and for the achievement of better athletic performance.