Study protocol for a comparative randomized controlled trial of Tai Chi and conventional exercise training on alleviating depression in older insomniacs

Background

Insomnia and depression are prevalent mental disorders that are often comorbid among older adults. Lifestyle intervention strategies incorporating Tai Chi or conventional exercise have been shown to alleviate symptoms of insomnia and depression. However, the comparative efficacy of these exercise modalities in individuals with both disorders has yet to be determined. Therefore, the aim of this study is to examine the efficacy of Tai Chi and conventional exercise for reducing depressive symptoms in older adults with chronic insomnia and depressive symptoms, when compared to a health education control.

Methods

This study is a prospective, assessor-blinded, three-arm, parallel group, randomized controlled trial. Older adults aged ≥60 years with a diagnosis of chronic insomnia and depressive symptoms will be randomly assigned to a Tai Chi, conventional exercise or health education control condition on a 1:1:1 basis. Interventions will last for 3 months, with a 6-month follow-up period. The primary outcome is depressive symptoms, assessed using the Hospital Anxiety and Depression Scale. Secondary outcomes include subjective sleep quality, 7-day actigraphy, 7-day sleep diary, anxiety symptoms, quality of life, medication usage and physical function. All measurements will be conducted at baseline, 3 months and 9 months by outcome assessors who are blinded to group allocation.

Discussion

This study will compare the efficacy of Tai Chi and conventional exercise in improving depression outcomes in older adults with chronic insomnia and depressive symptoms. Our results will shed light on the clinical potential of these interventions for combating insomnia and depression in older adults.

Effectiveness of Exercise, Cognitive Behavioral Therapy, and Pharmacotherapy on Improving Sleep in Adults with Chronic Insomnia: A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials

Despite the well-established treatment effectiveness of exercise, cognitive behavioral therapy for insomnia (CBT-I), and pharmacotherapy on improving sleep, there have been no studies to compare their long-term effectiveness, which is of clinical importance for sustainable management of chronic insomnia. This study compared the long-term effectiveness of these three interventions on improving sleep in adults with chronic insomnia. MEDLINE, PsycINFO, Embase, and SPORTDiscus were searched for eligible reports. Trials that investigated the long-term effectiveness of these three interventions on improving sleep were included. The post-intervention follow-up of the trial had to be ≥6 months to be eligible. The primary outcome was the long-term effectiveness of the three interventions on improving sleep. Treatment effectiveness was the secondary outcome. A random-effects network meta-analysis was carried out using a frequentist approach. Thirteen trials were included in the study. After an average post-intervention follow-up period of 10.3 months, both exercise (SMD, -0.29; 95% CI, -0.57 to -0.01) and CBT-I (-0.48; -0.68 to -0.28) showed superior long-term effectiveness on improving sleep compared with control. Temazepam was the only included pharmacotherapy, which demonstrated superior treatment effectiveness (-0.80; -1.25 to -0.36) but not long-term effectiveness (0.19; -0.32 to 0.69) compared with control. The findings support the use of both exercise and CBT-I for long-term management of chronic insomnia, while temazepam may be used for short-term treatment.

Dose-response effects of exercise and caloric restriction on visceral adiposity in overweight and obese adults: a systematic review and meta-analysis of randomised controlled trials

OBJECTIVE

To determine and compare the dose-response effects of exercise and caloric restriction on visceral adipose tissue in overweight and obese adults, while controlling for the weekly energy deficit induced by the interventions.

METHODS

PubMed, Embase, CINAHL and Web of Science were searched for randomised controlled trials comparing exercise or caloric restriction against eucaloric controls in overweight or obese adults. The primary outcome was the change in visceral fat measured by CT or MRI. Meta-analyses and meta-regressions were performed to determine the overall effect size (ES) and the dose-dependent relationship of exercise and caloric restriction on visceral fat. Heterogeneity, risk of bias and the certainty of evidence were also assessed.

RESULTS

Forty randomised controlled trials involving 2190 participants were included. Overall, exercise (ES -0.28 (-0.37 to -0.19); p<0.001; I2=25%) and caloric restriction (ES -0.53 (-0.71 to -0.35); p<0.001; I2=33%) reduced visceral fat compared with the controls. Exercise demonstrated a dose-response effect of -0.15 ((-0.23 to -0.07); p<0.001) per 1000 calories deficit per week, whereas the effect of caloric restriction was not dose-dependent (ES 0.03 (-0.12 to 0.18); p=0.64). Most of the studies showed a moderate risk of bias.

CONCLUSIONS

These findings support the dose-dependent effects of exercise to reduce visceral fat in overweight and obese adults. Caloric restriction did not demonstrate a dose-response relationship, although this may be attributed to the smaller number of studies available for analysis, compared with exercise studies.

PROSPERO REGISTRATION NUMBER

CRD42020210096.

Effects of exercise intensity and frequency on improving cognitive performance in middle-aged and older adults with mild cognitive impairment: A pilot randomized controlled trial on the minimum physical activity recommendation from WHO

Background: The World Health Organization physical activity guidelines recommend adults and older adults to accumulate at least 150–300 min of moderate or 75–150 min of vigorous aerobic-type physical activity weekly for health benefits including improvements of cognitive performance. However, the optimal exercise intensity and frequency for maximizing the cognitive benefits remain unclear.

Purpose: We conducted a parallel, assessor-blinded, pilot randomized controlled trial to evaluate the effectiveness of different intensities and frequencies of the WHO-recommended minimal volume of aerobic-type physical activity on improving cognitive performance in middle-aged and older adults with mild cognitive impairment (MCI).

Methods: Participants were randomly allocated to the stretching exercise control group (CON), once-a-week and thrice-a-week moderate-intensity walking groups (M1 and M3), and once-a-week and thrice-a-week vigorous-intensity walking groups (V1 and V3). Intervention duration was 12 weeks. The primary outcome was global cognitive performance assessed by the Hong Kong version of Montreal Cognitive Assessment. Secondary outcomes were self-report and objective cognitive performances, mental health, sleep quality, and cardiorespiratory fitness.

Results: Thirty-seven participants completed the study (CON: n = 7, M1: n = 7, M3: n = 7, V1: n = 8, V3: n = 8). Participants in all four walking exercise groups demonstrated significant improvements in global cognitive performance assessed by the Hong Kong version of the Montreal Cognitive Assessment after the intervention when compared to CON (p < 0.001). The walking exercise interventions also significantly mitigated the anxiety severity (p < 0.005) and improved the cardiorespiratory fitness (p < 0.05) of the participants in the walking exercise groups.

Conclusion: 150-min moderate- or 75-min vigorous-intensity walking exercise performed once- or thrice-weekly showed similar effects on improving cognitive performance in middle-aged and older adults with MCI. The 12-week walking exercise interventions also reduced anxiety severity and improved cardiorespiratory fitness of the participants.

Clinical Trial Registration:clinicaltrials.gov, identifier NCT04515563

Comparison of moderate and vigorous walking exercise on reducing depression in middle-aged and older adults: A pilot randomized controlled trial

The optimal intensity of physical activity for alleviating depression in middle-aged and older adults remains unclear. The comparative effects of moderate and vigorous physical activity on reducing depression have not been directly examined. The World Health Organization (WHO) physical activity guidelines recommend adults and older adults to accumulate at least 150-300 minutes of moderate or 75-150 minutes of vigorous aerobic-type physical activity weekly or an equivalent combination of both for health benefits including reduced risk of depression. This parallel, assessor-blinded, pilot randomized controlled trial preliminarily compared the effectiveness of the minimal volume of aerobic-type physical activity at different intensities as recommended by WHO (150 minutes of moderate walking exercise and 75 minutes of vigorous walking exercise weekly) on alleviating depression in middle-aged and older adults. Middle-aged and older adults diagnosed with depression were randomized to the control group (CON), moderate walking exercise group (MOD), or vigorous walking exercise group (VIG). The exercise frequency of the moderate and vigorous walking exercise were three times a week and the intervention duration were 12 weeks. The primary outcome was the severity of depression assessed by Beck Depression Inventory. Secondary outcomes included severity of anxiety, sleep quality, quality of life, and cardiorespiratory fitness. Thirty participants completed the study (CON: n = 10, MOD: n = 10, VIG: n = 10). Participants in both MOD and VIG had significantly decreased depression severity after the intervention compared to CON (both p < 0.001). There was no significant difference between MOD and VIG (p = 0.92). Both MOD and VIG interventions also mitigated anxiety severity, improved quality of life and cardiorespiratory fitness. The minimum volume of walking exercise at either moderate or vigorous intensity was found to alleviate depression in middle-aged and older adults.Trial registration: ClinicalTrials.gov identifier: NCT04403373..

Effects of Exercise Frequency and Intensity on Reducing Depressive Symptoms in Older Adults With Insomnia: A Pilot Randomized Controlled Trial

Background

The effects of exercise frequency and intensity on alleviating depressive symptoms in older adults with insomnia are unclear.

Purpose

The purpose of this study was to investigate the influence of different exercise frequencies and intensities on prescribed aerobic-type physical activity (i.e., 75 min of vigorous-intensity exercise or 150 min of moderate-intensity exercise weekly) for reducing depressive symptoms in older adults living with insomnia, as recommended by the WHO.

Design

This study is a randomized, controlled, assessor-blinded trial.

Setting

This study is conducted at a single research site in Hong Kong.

Participants

This study includes older adults aged 50 years or above with depressive symptoms and insomnia.

Intervention

Participants were randomly assigned in a 1:1:1:1:1 ratio to the following groups: attention control (CON), moderate walking once weekly (MOD × 1/week), moderate walking thrice weekly (MOD × 3/week), vigorous walking once weekly (VIG × 1/week), and vigorous walking thrice weekly (VIG × 3/week). The total weekly exercise volumes among the walking groups were matched to the minimum recommended physical activity volume.

Measurements

Depression, anxiety, self-perceived sleep quality, insomnia severity, actigraphy-assessed 7-day sleep data, 7-day sleep diary, cardiorespiratory fitness, adherence, and habitual physical activity were examined at baseline and after 12 weeks of intervention.

Results

Both MOD × 3/week and VIG × 3/week groups demonstrated reduced depression (Hospital Anxiety and Depression Scale [HADS] – Depression: MOD × 3/wk: −68.6%; VIG × 3/week: −67.4%) and anxiety levels (HADS – Anxiety: MOD × 3/week: −54.3%; VIG × 3/week: −59.8%) compared with CON (both p < 0.01). Self-perceived sleep quality was improved in MOD × 3/week (−31.4% of the Pittsburgh Sleep Quality Index [PSQI]), VIG × 1/week (−34.1% of PSQI), and VIG × 3/week (−38.3% of PSQI), but not in MOD × 1/week, when compared with CON (p < 0.05). No serious adverse events were observed in this study.

Conclusion

The effects of walking training on reducing depressive symptoms appeared to be dependent on exercise frequency. Our findings suggest that three sessions of walking per week at either moderate or vigorous-intensity effectively alleviate depressive symptoms in older adults with insomnia. Additional research is needed to further verify the effects of exercise frequency on depression.

Clinical Trial Registration

[ClinicalTrials.gov], identifier [NCT04354922].

Effects of Tai Chi or Conventional Exercise on Central Obesity in Middle-Aged and Older Adults : A Three-Group Randomized Controlled Trial

BACKGROUND

Central obesity is a major manifestation of metabolic syndrome, which is a common health problem in middle-aged and older adults.

OBJECTIVE

To examine the therapeutic efficacy of tai chi for management of central obesity.

DESIGN

Randomized, controlled, assessor-blinded trial. (ClinicalTrials.gov: NCT03107741).

SETTING

A single research site in Hong Kong between 27 February 2016 and 28 February 2019.

PARTICIPANTS

Adults aged 50 years or older with central obesity.

INTERVENTION

543 participants were randomly assigned in a 1:1:1 ratio to a control group with no exercise intervention (n = 181), conventional exercise consisting of aerobic exercise and strength training (EX group) (n = 181), and a tai chi group (TC group) (n = 181). Interventions lasted 12 weeks.

MEASUREMENTS

Outcomes were assessed at baseline, week 12, and week 38. The primary outcome was waist circumference (WC). Secondary outcomes were body weight; body mass index; high-density lipoprotein cholesterol (HDL-C), triglyceride, and fasting plasma glucose levels; blood pressure; and incidence of remission of central obesity.

RESULTS

The adjusted mean difference in WC from baseline to week 12 in the control group was 0.8 cm (95% CI, -4.1 to 5.7 cm). Both intervention groups showed reductions in WC relative to control (adjusted mean differences: TC group vs. control, -1.8 cm [CI, -2.3 to -1.4 cm]; P < 0.001; EX group vs. control: -1.3 cm [CI, -1.8 to -0.9 cm]; P < 0.001); both intervention groups also showed reductions in body weight (P < 0.05) and attenuation of the decrease in HDL-C level relative to the control group. The favorable changes in WC and body weight were maintained in both the TC and EX groups, whereas the beneficial effect on HDL-C was only maintained in the TC group at week 38.

LIMITATIONS

High attrition and no dietary intervention.

CONCLUSION

Tai chi is an effective approach to reduce WC in adults with central obesity aged 50 years or older.

PRIMARY FUNDING SOURCE

Health and Medical Research Fund.

Effects of Tai Chi or Exercise on Sleep in Older Adults With Insomnia: A Randomized Clinical Trial

IMPORTANCE

Previous studies that have shown tai chi to improve sleep were mainly based on subjective assessments, which might have produced results confounded by self-reporting bias.

OBJECTIVE

To compare the effectiveness of tai chi for improving sleep in older adults with insomnia with conventional exercise and a passive control group using actigraphy-based objective measurements.

DESIGN, SETTING, AND PARTICIPANTS

This randomized, 3-arm, parallel group, assessor-masked clinical trial was conducted at a single research unit in Hong Kong between August 2014 and August 2018. Eligible participants, aged 60 years or older and with chronic insomnia, were randomly allocated into tai chi training, exercise, and control groups.

INTERVENTIONS

12-week tai chi training, 12-week conventional exercise, and no intervention control.

MAIN OUTCOMES AND MEASURES

Primary outcomes were measures taken from actigraphy sleep assessment. Secondary outcomes included remission of insomnia, insomnia treatment response, Pittsburgh Sleep Quality Index score, Insomnia Severity Index score, and self-reported sleep using a 7-day sleep diary. Assessments were performed at baseline, end of the intervention (postintervention), and 24 months after the intervention (follow-up). Data analysis was performed from September 2018 to August 2020.

RESULTS

A total of 320 participants (mean [SD] age, 67.3 [6.8] years; mean [SD] insomnia duration, 124.4 [134.5] months; 256 [80.0%] women) were randomly allocated into control (110 participants), exercise (105 participants), and tai chi (105 participants) groups and included in the data analysis. Compared with the control group, the exercise and tai chi groups showed improved sleep efficiency (exercise vs control: adjusted mean difference, +3.5%; 95% CI, 1.8-5.2; P < .001; tai chi vs control: adjusted mean difference, +3.4%; 95% CI, 1.6-5.1; P < .001) and reductions of wake time after sleep onset (exercise vs control: -17.0 minutes; 95% CI, -24.9 to -9.0; P < .001; tai chi vs control: -13.3 minutes; 95% CI, -21.3 to -5.2; P = .001) and number of awakenings (exercise vs control: -2.8 times; 95% CI, -4.0 to -1.6; P < .001; tai chi vs control: -2.2 times; 95% CI, -3.5 to -1.0; P < .001) as assessed by actigraphy at postintervention; although there were no significant differences between the exercise and tai chi groups. The actigraphy-assessed beneficial effects were maintained in both intervention groups at follow-up.

CONCLUSIONS AND RELEVANCE

Conventional exercise and tai chi improved sleep and the beneficial effects sustained for 24 months, although the absolute improvements in sleep parameters were modest. Improvements in objective sleep parameters were not different between the tai chi and exercise groups, suggesting that tai chi can be an alternative approach for managing insomnia.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02260843.

Obestatin and growth hormone reveal the interaction of central obesity and other cardiometabolic risk factors of metabolic syndrome

Metabolic syndrome (MetS) is a multi-factorial disorder including central obesity (CO), insulin resistance, hyperglycemia, dyslipidemia and hypertension which increases the risk of diabetes mellitus and cardiovascular diseases. CO is considered as an essential component of MetS according to International Diabetes Federation (IDF), which may further modulate distinct signalling pathways compared with the other four MetS risk factors. Given that ghrelin signalling and the growth hormone/insulin-like growth factor-1 (GH/IGF-1) axis regulates energy balance and metabolic homeostasis, this study examined the changes in various ghrelin products and circulating hormones in response to the interaction between CO and other MetS components including blood pressure, fasting blood glucose, triglycerides, and high-density lipoprotein cholesterol in 133 Hong Kong Chinese adults. Circulating obestatin and GH were increased and reduced, respectively, by either CO or the other 4-risk factor cluster. These changes were further augmented by the presence of all MetS risk factors. However, changes of ghrelin levels were not mediated by CO but the other MetS risk factors. Our findings suggest that CO does not predict all the dysregulation of signalling pathways in individuals with MetS. Although CO and other MetS may share common signalling targets (i.e., obestatin and GH), CO does not contribute to the perturbation of ghrelin signalling.

One Year of Yoga Training Alters Ghrelin Axis in Centrally Obese Adults With Metabolic Syndrome

Introduction: Metabolic syndrome (MetS) is a multiplex cardiometabolic manifestation associated with type 2 diabetes mellitus and cardiovascular diseases. Yoga training has been shown to alleviate MetS. Recently, circulatory ghrelin profile was demonstrated to be associated with MetS. This study examined the effects of 1 year of yoga training on β-cell function and insulin resistance, and the involvement of metabolic peptides, including unacylated ghrelin (UnAG), acylated ghrelin (AG), obestatin, growth hormone (GH), and insulin, in the beneficial effects of yoga training in centrally obese adults with MetS. Methods: This was a follow up study, in which data of risk factors of MetS, physical performance tests [resting heart rate (HR), chair stand test (CS), chair sit and reach test (CSR), back scratch test (BS), and single leg stand tests (SLS)] and serum samples of 79 centrally obese MetS subjects aged 58 ± 8 years (39 subjects received 1-year yoga training and 40 subjects received no training) were retrieved for analyses. β-cell function and insulin resistance were examined by Homeostasis Model Assessment (HOMA). Circulating levels of UnAG, AG, obestatin, GH, and insulin were determined by enzyme-linked immunosorbent assay using fasting serum samples. Generalized estimating equation analysis and Mann-Whitney U-test were used to detect statistically significant differences between groups. Results: Waist circumference (WC) was significantly decreased after yoga intervention (control: +2%; yoga: -4%). Significant improvements in HR (control: +2%; yoga: -5%), CS (control: -1%; yoga: +24%), CSR left (control: worsen by 0.90 cm; yoga: improved by 4.21 cm), CSR right (control: worsen by 0.75 cm; yoga: improved by 4.28 cm), right side of BS (control: improved by 0.19 cm; yoga: improved by 4.31 cm), SLS left (control: -10%; yoga: +86%), and SLS right (control: -6%; yoga: +47%) were observed after 1-year yoga training. No significant difference was found between the two groups in insulin, HOMA indices, and disposition index. Yoga training significantly increased circulating GH (control: -3%; yoga: +22%), total circulating ghrelin (control: -26%; yoga: +13%), and UnAG (control: -27%; yoga: +14%), whereas decreased AG (control: -7%; yoga: -33%) and obestatin (control: +24%; yoga: -29%). Conclusion: One-year of yoga training modulated total ghrelin, UnAG, AG, obestatin, and GH while exerting beneficial effects on physical functions and central obesity in adults with MetS. The beneficial effects of yoga may be associated with the alteration of ghrelin gene product and GH.

Adipokines demonstrate the interacting influence of central obesity with other cardiometabolic risk factors of metabolic syndrome in Hong Kong Chinese adults

OBJECTIVE

Metabolic syndrome (MetS) or prediabetes is a complex disorder that is defined by a clustering of cardiometabolic risk factors, including obesity, hypertriglyceridemia, reduced high-density lipoprotein (HDL) cholesterol, hypertension, and insulin resistance. Among cardiometabolic risk factors, central obesity plays a key role in the development of MetS through alterations in the secretion of adipokines and interacts with other MetS risk factors to unfavorably influence overall cardiometabolic risk. Obesity has grasped epidemic proportions in Asia, which has the highest number of people with diabetes in the world. But, the importance of central obesity in the clustering of all four MetS risk factors or vice versa in predicting severity of MetS has not yet been investigated in Asian population. Therefore, the present study examined the influence of central obesity on circulating levels of adipokines through its interaction with the clustering of cardiometabolic risk factors of MetS including hyperglycemia, hypertriglyceridemia, dyslipidemia and hypertension in Hong Kong Chinese adults.

SUBJECTS

Blood samples from 83 Hong Kong Chinese adults, who were previously screened for MetS according to the guideline of the United States National Cholesterol Education Program Expert Panel Adult Treatment Panel III criteria were selected. Insulin and adipokines, including visfatin, chemerin, plasminogen activator inhibitor-1 (PAI-1), resistin, C-C motif chemokine ligand 2 (CCL-2), interleukin-6 (IL-6), interleukin-8 (IL-8), interleukin-10 (IL-10), tumour necrosis factor-α (TNF-α), leptin and adiponectin were assessed.

RESULTS

The interacting effect of central obesity with all of the other four MetS risk factors increased the proinflammatory status of adipokines (TNF-α, leptin) and decreased the anti-inflammatory status of adipokine (adiponectin).

CONCLUSION

Our results indicate that the inflammatory status of MetS may be more severe in the presence of central obesity. Adipokines, as biomarkers for pathophysiological changes, may help to improve early patient identification and to predict MetS-associated morbidity and mortality.

Revealing the Neural Mechanisms Underlying the Beneficial Effects of Tai Chi: A Neuroimaging Perspective

Tai Chi Chuan (TCC), a traditional Chinese martial art, is well-documented to result in beneficial consequences in physical and mental health. TCC is regarded as a mind-body exercise that is comprised of physical exercise and meditation. Favorable effects of TCC on body balance, gait, bone mineral density, metabolic parameters, anxiety, depression, cognitive function, and sleep have been previously reported. However, the underlying mechanisms explaining the effects of TCC remain largely unclear. Recently, advances in neuroimaging technology have offered new investigative opportunities to reveal the effects of TCC on anatomical morphologies and neurological activities in different regions of the brain. These neuroimaging findings have provided new clues for revealing the mechanisms behind the observed effects of TCC. In this review paper, we discussed the possible effects of TCC-induced modulation of brain morphology, functional homogeneity and connectivity, regional activity and macro-scale network activity on health. Moreover, we identified possible links between the alterations in brain and beneficial effects of TCC, such as improved motor functions, pain perception, metabolic profile, cognitive functions, mental health and sleep quality. This paper aimed to stimulate further mechanistic neuroimaging studies in TCC and its effects on brain morphology, functional homogeneity and connectivity, regional activity and macro-scale network activity, which ultimately lead to a better understanding of the mechanisms responsible for the beneficial effects of TCC on human health.

Adipokine Profiling in Adult Women With Central Obesity and Hypertension

Central obesity and hypertension are common risk factors for the metabolic syndrome, cardiovascular and renal diseases. Studies have shown that it is more difficult to control blood pressure and prevent end-organ damage in obese individuals with hypertension compared to their non-obese counterparts, especially among women. Obese females have a 6 times higher risk of developing hypertension than non-obese females while obese males are at a 1.5 times higher risk of developing hypertension, compared to their non-obese counterparts. Indeed, the inter-relationship between obesity and hypertension is unclear. Adipokines have been proposed to play a mediating role in the relationship between obesity and hypertension and are involved in the pathogenesis of metabolic diseases. Therefore, this study sought to determine the role of adipokines (adiponectin, plasminogen activator inhibitor-1, leptin, and tumor necrosis factor-α) in hypertensive Hong Kong Chinese women with central obesity. A total of 387 women aged 58 ± 11 years who were examined with a 2 × 2 factorial design for central obesity (waist circumference ≥ 80 cm) and hypertension (blood pressure ≥ 140/90 mmHg), were recruited from a pool of 1,492 Hong Kong Chinese adults who were previously screened for metabolic syndrome. Subjects with hyperglycemia, hypertriglyceridemia, and dyslipidemia were excluded to eliminate confounding effects. Our findings revealed that hypertensive women with central obesity had a lower anti-inflammatory status (adiponectin) and a higher pro-inflammatory status (TNF-α) than obese alone or hypertensive alone women. Also, women with central obesity had higher circulatory PAI-1 and leptin concentrations than their non-obese counterparts. We conclude that obesity may shift toward a more pro-inflammatory state and may become more severe in the presence of hypertension or vice versa.

Ablation of Bax and Bak protects skeletal muscle against pressure-induced injury

Pressure-induced injury (PI), such as a pressure ulcer, in patients with limited mobility is a healthcare issue worldwide. PI is an injury to skin and its underlying tissue such as skeletal muscle. Muscle compression, composed of mechanical deformation of muscle and external load, leads to localized ischemia and subsequent unloading reperfusion and, hence, a pressure ulcer in bed-bound patients. Although the gross factors involved in PI have been identified, little is known about the exact disease mechanism or its links to apoptosis, autophagy and inflammation. Here, we report that PI is mediated by intrinsic apoptosis and exacerbated by autophagy. Conditional ablation of Bax and Bak activates the Akt-mTOR pathway and Bnip3-mediated mitophagy and preserves mitochondrial contents in compressed muscle. Moreover, we find that the presence/absence of Bax and Bak alters the roles and functions of autophagy in PI. Our results suggest that manipulating apoptosis and autophagy are potential therapeutic targets for treatment and prevention of PI.

Yoga training modulates adipokines in adults with high-normal blood pressure and metabolic syndrome

Metabolic syndrome (MetS) is associated with diabetes mellitus and cardiovascular diseases. Our previous study indicated that people with MetS showed a decrease in waist circumference and a decreasing trend in blood pressure after 1-year yoga. This study investigated the effect of yoga on MetS people with high-normal blood pressure by exploring modulations in proinflammatory adipokines (leptin, chemerin, visfatin, and plasminogen activator inhibitor-1 or PAI-1) and an anti-inflammatory adipokine (adiponectin). A total of 97 Hong Kong Chinese individuals aged 57.6 ± 9.1 years with MetS and high-normal blood pressure were randomly assigned to control (n = 45) and yoga groups (n = 52). Participants in the control group were not given any intervention but were contacted monthly to monitor their health status. Participants in the yoga group underwent a yoga training program with three 1-hour yoga sessions weekly for 1 year. The participants' sera were harvested and assessed for adipokines. Generalized estimating equation (GEE) was used to examine the interaction effect between 1-year time (pre vs post), and intervention (control vs yoga). GEE analyses revealed significant interaction effects between 1-year time and yoga intervention for the decreases in leptin and chemerin and the increase in adiponectin concentration in the sera examined. These results demonstrated that 1-year yoga training decreased proinflammatory adipokines and increased anti-inflammatory adipokine in adults with MetS and high-normal blood pressure. These findings support the beneficial role of yoga in managing MetS by favorably modulating adipokines.

Association of Markers of Proinflammatory Phenotype and Beige Adipogenesis with Metabolic Syndrome in Chinese Centrally Obese Adults

BACKGROUND

Visceral adiposity is associated with higher productions of C-reactive protein (CRP) and interleukin-6 (IL-6). Inflammation of obese adipose tissues could contribute to systemic metabolic dysregulation, especially thermogenic activity of white adipose tissues, namely, beige adipogenesis, characterized by altered irisin expression. Thus, we investigated the roles of inflammation and adipocyte beiging in Chinese centrally obese (CO) adults with metabolic syndrome (MetS).

METHODS

This cross-sectional study was conducted on 54 CO and 58 non-CO subjects drawn from 1492 Chinese people with age and sex matched during November 2010 and August 2013. Twenty (37.0%) of the CO subjects fulfilled the IDF worldwide definition of MetS. Serum CRP, IL-6, and irisin levels were examined.

RESULTS

Higher CRP and IL-6, but lower irisin, levels were manifested in MetS versus non-MetS subjects with or without CO. Multiple linear regression identified high-density lipoprotein cholesterol level as the only independent risk factor for irisin level. Categorized by median of CRP and IL-6 levels, a lower irisin level was only observed in high CRP group.

CONCLUSION

Under the condition of central obesity, chronic inflammation and impaired beige adipogenesis are associated with MetS in Chinese adults.

Ghrelin Axis Reveals the Interacting Influence of Central Obesity and Hypertension

Objective: This study aimed to investigate how central obesity and hypertension modulate unacylated ghrelin (UnAG), acylated ghrelin (AG), obestatin, growth hormone (GH), and the ratios of UnAG/obestatin, AG/obestatin, and total ghrelin/obestatin. Methods: Circulatory abundances of UnAG, AG, obestatin and GH were determined in 387 Hong Kong Chinese female adults with age between 24 to 86 years based on a 2 × 2 factorial design of hypertension (blood pressure ≥140/90 mmHg) and central obesity (waist circumference or WC ≥80 cm). Participants were categorized as neither hypertensive nor centrally obese (NHNO; n = 105), hypertensive but not centrally obese (HNO; n = 102), centrally obese but not hypertensive (NHO; n = 74) and hypertensive and centrally obese (NO; n = 106). Pearson's correlation analyses were performed to detect the association between the peptides examined with WC and blood pressure. The main and interaction effects of hypertension and central obesity were examined by generalized estimating equations analyses. Results: Correlation analyses revealed that systolic blood pressure was negatively correlated with AG/obestatin, UnAG/obestatin and total ghrelin/obestatin ratios, AG, total ghrelin, and GH, while diastolic blood pressure was negatively correlated with UnAG/obestatin, total ghrelin/obestatin ratios, and GH. WC was negatively correlated with AG/obestatin, UnAG/obestatin, and total ghrelin/obestatin ratios, UnAG, AG, total ghrelin, GH, and obestatin. Interaction effects of hypertension and central obesity were observed on UnAG/obestatin, AG/obestatin and total ghrelin/obestatin ratios, and obestatin. Obestatin in NHO group was significantly higher compared to NHNO and HO groups. UnAG/obestatin, AG/obestatin, and total ghrelin/obestatin ratios were higher in NHNO group compared to HNO and HO groups. Main effects of central obesity and hypertension were observed in UnAG, total ghrelin and GH. The HO group manifested the lowest level of UnAG, total ghrelin and GH among all the groups studied. Main effect of hypertension was observed on AG, suggesting that hypertensive individuals exhibited lower levels of AG regardless of central obesity. Conclusion: Circulatory ghrelin gene products and GH exhibit different modes of modulation in response to the co-manifestation of multiple cardiovascular risk factors compared with a single risk factor alone.

Protective Effect of Unacylated Ghrelin on Compression-Induced Skeletal Muscle Injury Mediated by SIRT1-Signaling

Unacylated ghrelin, the predominant form of circulating ghrelin, protects myotubes from cell death, which is a known attribute of pressure ulcers. In this study, we investigated whether unacylated ghrelin protects skeletal muscle from pressure-induced deep tissue injury by abolishing necroptosis and apoptosis signaling and whether these effects were mediated by SIRT1 pathway. Fifteen adult Sprague Dawley rats were assigned to receive saline or unacylated ghrelin with or without EX527 (a SIRT1 inhibitor). Animals underwent two 6-h compression cycles with 100 mmHg static pressure applied over the mid-tibialis region of the right limb whereas the left uncompressed limb served as the intra-animal control. Muscle tissues underneath the compression region, and at the similar region of the opposite uncompressed limb, were collected for analysis. Unacylated ghrelin attenuated the compression-induced muscle pathohistological alterations including rounding contour of myofibers, extensive nucleus accumulation in the interstitial space, and increased interstitial space. Unacylated ghrelin abolished the increase in necroptosis proteins including RIP1 and RIP3 and attenuated the elevation of apoptotic proteins including p53, Bax, and AIF in the compressed muscle. Furthermore, unacylated ghrelin opposed the compression-induced phosphorylation and acetylation of p65 subunit of NF-kB. The anti-apoptotic effect of unacylated ghrelin was shown by a decrease in apoptotic DNA fragmentation and terminal dUTP nick-end labeling index in the compressed muscle. The protective effects of unacylated ghrelin vanished when co-treated with EX527. Our findings demonstrated that unacylated ghrelin protected skeletal muscle from compression-induced injury. The myoprotective effects of unacylated ghrelin on pressure-induced tissue injury were associated with SIRT1 signaling.

Effects of long-term resveratrol-induced SIRT1 activation on insulin and apoptotic signalling in aged skeletal muscle

AIMS

Activation of Foxo1 is known to promote apoptosis and disturbances to insulin signalling. However, their modulating roles in aged skeletal muscle are not clear. The present study tested the hypothesis that long-term (i.e. 8 month) resveratrol supplementation would improve physical traits including exercise capacity and basal voluntary activity of aged mice and modulate insulin/apoptotic signalling in aged skeletal muscle. This study also examined whether these resveratrol-associated alterations would involve orchestration of the SIRT1-Foxo1 signalling axis.

METHODS

Two-month-old SAMP8 mice were randomly assigned to young, aged and aged with resveratrol treatment (AR) groups. The AR mice were supplemented with 4.9 mg(-1) kg(-1) day(-1) resveratrol for 8 months. All animals were subject to endurance capacity test and voluntary motor behaviour assessment. The lateral gastrocnemius muscle tissues were harvested for further analyses.

RESULTS

Long-term resveratrol treatment significantly alleviated the age-associated reductions in exercise capacity and voluntary motor behaviour. The protein content, but not the deacetylase activity of SIRT1 was increased with concomitant elevations of p300 acetylase and acetylation of Foxo1 in aged muscle. The aged muscle also manifested signs of impaired insulin signalling including attenuated phosphorylation of Akt, activity of pyruvate dehydrogenase and membrane trafficking of GLUT4 and elevated levels of phosphorylated IRS1 and iNOS and apoptotic activation measured as Bim, p53 and apoptotic DNA fragmentation. Intriguingly, all these age-related adverse changes were mitigated with the activation of SIRT1 deacetylase activity after long-term resveratrol treatment.

CONCLUSIONS

These data suggest that modulation of the SIRT1-Foxo1 axis by long-term resveratrol treatment enhances physical traits and alleviates the unfavourable changes in insulin and apoptotic signalling in aged muscle.

Acute Treatment of Resveratrol Alleviates Doxorubicin-Induced Myotoxicity in Aged Skeletal Muscle Through SIRT1-Dependent Mechanisms

Study of the exacerbating effects of chemotherapeutics, such as doxorubicin, on the impairment of insulin metabolic signaling in aged skeletal muscle is very limited. Here, we tested the hypothesis that activation of sirtuin 1 deacetylase activity by resveratrol would prevent the disruption of insulin signaling and augmentation of catabolic markers induced by doxorubicin in aged skeletal muscle. Two- and 10-month-old senescence-accelerated mice (prone 8) were randomized to receive saline, doxorubicin, doxorubicin and resveratrol, or a combination of doxorubicin, resveratrol, and sirtinol or EX527. Doxorubicin reduced the sirtuin 1 activity without affecting the phosphorylation levels of IRS1(Ser307), mTOR(Ser2481), Akt(Thr308/Ser473), membranous glucose transporter 4, protein abundance of PDK4, and enzymatic activity of pyruvate dehydrogenase in aged muscles. Intriguingly, resveratrol attenuated the doxorubicin-induced elevations of apoptotic and catabolic markers measured as Bax, caspase 3 activity, apoptotic DNA fragmentation, MuRF-1, ubiquitinated proteins, and proteasomal activity in aged muscles, whereas these beneficial effects were abolished on inhibition of sirtuin 1 by sirtinol or EX527. Markers of insulin signaling were not affected by doxorubicin or resveratrol in the senescent skeletal muscle. Nevertheless, the antiapoptotic and anticatabolic effects of resveratrol in aged skeletal muscle treated with doxorubicin were mediated in a sirtuin 1-dependent signaling manner.

[D-Lys3]-GHRP-6 exhibits pro-autophagic effects on skeletal muscle

[D-Lys3]-GHRP-6 is regarded as a highly selective growth-hormone secretagogue receptor (GHSR) antagonist and has been widely used to investigate the dependency of GHSR-1a signalling mediated by acylated ghrelin. However, [D-Lys3]-GHRP-6 has been reported to influence other cellular processes which are unrelated to GHSR-1a. This study aimed to examine the effects of [D-Lys3]-GHRP-6 on autophagic and apoptotic cellular signalling in skeletal muscle. [D-Lys3]-GHRP-6 enhanced the autophagic signalling demonstrated by the increases in protein abundances of beclin-1 and LC3 II-to-LC3 1 ratio in both normal muscle and doxorubicin-injured muscle. [D-Lys3]-GHRP-6 reduced the activation of muscle apoptosis induced by doxorubicin. No histological abnormalities were observed in the [D-Lys3]-GHRP-6-treated muscle. Intriguingly, the doxorubicin-induced increase in centronucleated muscle fibres was not observed in muscle treated with [D-Lys3]-GHRP-6, suggesting the myoprotective effects of [D-Lys3]-GHRP-6 against doxorubicin injury. The [D-Lys3]-GHRP-6-induced activation of autophagy was found to be abolished by the co-treatment of CXCR4 antagonist, suggesting that the pro-autophagic effects of [D-Lys3]-GHRP-6 might be mediated through CXCR4. In conclusion, [D-Lys3]-GHRP-6 exhibits pro-autophagic effects on skeletal muscle under both normal and doxorubicin-injured conditions.

Effects of 1-year yoga on cardiovascular risk factors in middle-aged and older adults with metabolic syndrome: a randomized trial

BACKGROUND

Metabolic syndrome (MetS) is a clustering of cardiovascular risk factors, which is associated with diabetes mellitus and cardiovascular disease. Lifestyle interventions applied to people with MetS has considerable beneficial effects on disease preventive outcomes. This study aimed to examine the effects of 1-year of yoga exercise on the cardiovascular risk factors including central obesity, hypertension, dyslipidemia and hyperglycemia in middle-aged and older Hong Kong Chinese adults with MetS.

METHODS

Adults diagnosed with MetS using National Cholesterol Education Program criteria (n = 182; mean ± SD age = 56 ± 9.1) were randomly assigned to a 1-year yoga intervention group or control group. Systolic and diastolic blood pressure, waist circumference, fasting plasma glucose, triglycerides, and high-density lipoprotein cholesterol were examined at baseline, midway, and on completion of the study. Physical activity level and caloric intake were assessed and included in the covariate analyses.

RESULTS

A reduction of the number of diagnostic components for MetS was found to be associated with the yoga intervention. Waist circumference was significantly improved after the 1-year yoga intervention. A trend towards a decrease in systolic blood pressure was observed following yoga intervention.

CONCLUSION

These results suggest that yoga exercise improves the cardiovascular risk factors including central obesity and blood pressure in middle-aged and older adults with MetS. These findings support the complementary beneficial role of yoga in managing MetS.

Modulating effect of SIRT1 activation induced by resveratrol on Foxo1-associated apoptotic signalling in senescent heart

Elevations of cardiomyocyte apoptosis and fibrotic deposition are major characteristics of the ageing heart. Resveratrol, a polyphenol in grapes and red wine, is known to improve insulin resistance and increase mitochondrial biogenesis through the SIRT1-PGC-1α signalling axis. Recent studies attempted to relate SIRT1 activation by resveratrol to the regulation of apoptosis in various disease models of cardiac muscle. In the present study, we tested the hypothesis that long-term (8-month) treatment of resveratrol would activate SIRT1 and improve the cardiac function of senescent mice through suppression of Foxo1-associated pro-apoptotic signalling. Our echocardiographic measurements indicated that the cardiac systolic function measured as fractional shortening and ejection fraction was significantly reduced in aged mice when compared with the young mice. These reductions, however, were not observed in resveratrol-treated hearts. Ageing significantly reduced the deacetylase activity, but not the protein abundance of SIRT1 in the heart. This reduction was accompanied by increased acetylation of the Foxo1 transcription factor and transactivation of its target, pro-apoptotic Bim. Subsequent analyses indicated that pro-apoptotic signalling measured as p53, Bax and apoptotic DNA fragmentation was up-regulated in the heart of aged mice. In contrast, resveratrol restored SIRT1 activity and suppressed elevations of Foxo1 acetylation, Bim and pro-apoptotic signalling in the aged heart. In parallel, resveratrol also attenuated the ageing-induced elevations of fibrotic collagen deposition and markers of oxidative damage including 4HNE and nitrotyrosine. In conclusion, these novel data demonstrate that resveratrol mitigates pro-apoptotic signalling in senescent heart through a deacetylation mechanism of SIRT1 that represses the Foxo1-Bim-associated pro-apoptotic signalling axis.

The CHOICE trial: adalimumab demonstrates safety, fistula healing, improved quality of life and increased work productivity in patients with Crohn's disease who failed prior infliximab therapy

BACKGROUND

Adalimumab induces and maintains remission in adults with Crohn's disease.

AIM

To evaluate safety, fistula healing, quality of life and work productivity in adalimumab-treated patients who failed infliximab, including primary nonresponders.

METHODS

After a ≥8-week infliximab washout, patients with moderate-to-severe Crohn's disease received open-label adalimumab as induction (160/80 mg at weeks 0/2) and maintenance (40 mg every other week) therapies. At/after 8 weeks, patients with flare/nonresponse could receive weekly therapy. Minimum study duration was 8 weeks, continuing until the commercial availability of adalimumab for Crohn's disease.

RESULTS

Of 673 patients enrolled, 17% were infliximab primary nonresponders and 83% were initial responders. Three percent of patients had serious infections (mainly abscesses). Complete fistula healing was achieved by 34/88 (39%) patients with baseline fistulas. Improvements in quality of life and work productivity were sustained from week 4 to week 24 for all patients, as well as the subgroup of primary nonresponders.

CONCLUSIONS

Blinded clinical trials have shown adalimumab to be both an effective first-line therapy for anti-TNF-naïve patients and an important treatment option for infliximab-refractory or -intolerant patients. This trial presents open-label experience to support further the safety and effectiveness of adalimumab in patients who failed infliximab therapy, including primary nonresponders (NCT00338650).

Economic impact of switching from valsartan to other angiotensin receptor blockers in patients with hypertension

BACKGROUND

The approaching availability of lower-cost generic angiotensin receptor blockers (ARBs) may affect formulary policies for patients maintained on the ARB valsartan.

OBJECTIVE

Estimate the economic impact of switching from valsartan (including valsartan-based single-pill combinations) to other ARBs without apparent medical reasons.

RESEARCH DESIGN AND METHODS

Patients with essential hypertension and at least 6 months of continuous valsartan treatment free of hospitalization, cardiovascular events, renal events or ARB-associated adverse events were identified from the MarketScan administrative claims database from January 1, 2004 to March 31, 2008. Those who subsequently switched to a different ARB with at least a 5% copayment decrease (switchers) were matched to those who did not switch (maintainers) according to propensity score quintiles and selected baseline characteristics. Refills were not required after the index fill for the switched-to ARB or maintained valsartan. Matched switchers and maintainers were compared in terms of medication discontinuation, healthcare resource use and costs during the 6 months following the index fill.

RESULTS

A total of 99,926 valsartan maintainers and 2150 switchers (with a mean copayment decrease of $16.5 per month) were identified and matched. After matching, switching from versus maintaining valsartan was associated with an 8% higher risk of medication discontinuation (p < 0.008), 19.1 additional outpatient visits/100 patients (p = 0.002) and 9.3 additional hypertension-related inpatient days/100 patients (p = 0.030). Concurrently, switching from versus maintaining valsartan was associated with higher total medical costs by $748/patient (p < 0.001), driven largely by higher costs for hypertension-related medical services by $492/patient (p = 0.004).

LIMITATIONS

Exact reasons for switching were not available and the study assessed only the short-term impacts of switching.

CONCLUSIONS

Hypertension patients maintained on valsartan who switched to a different ARB with a lower copayment experienced substantial increases in medication discontinuation, healthcare resource use and costs compared to those who maintained valsartan treatment.

Systematic review: the costs of ulcerative colitis in Western countries

BACKGROUND

Early onset and complications such as hospitalization and surgery contribute to the economic burden of ulcerative colitis.

AIM

To review systematically the literature on costs of ulcerative colitis in Western countries.

METHODS

Studies estimating costs of ulcerative colitis in Western countries were identified using Medline, EMBASE and ISI Web of Science and were rated based on relevance and reliability of estimates. All costs were adjusted to 2008 currency values. A parallel review focused on the impact of disease severity on costs, hospitalizations and surgeries.

RESULTS

Estimated annual per-patient direct medical costs of ulcerative colitis ranged from $6217 to $11,477 in the United States and from euro8949 to euro10,395 in Europe. Hospitalizations accounted for 41-55% of direct medical costs. Indirect costs accounted for approximately one-third of total costs in the United States and 54-68% in Europe. Total economic burden of ulcerative colitis was estimated at $8.1-14.9 billion annually in the United States and at euro12.5-29.1 billion in Europe; total direct costs were $3.4-8.6 billion in the United States and euro5.4-12.6 billion in Europe. Direct costs, hospitalizations and surgeries increased with worsening disease severity.

CONCLUSIONS

Ulcerative colitis is a costly disease. Hospitalizations contribute significantly to direct medical costs, and indirect costs are considerable, having previously been substantially underestimated.

Asthma severity categorization using a claims-based algorithm or pulmonary function testing

OBJECTIVES

This study was performed to determine whether pulmonary function test results would appreciably alter asthma severity categorization determined by an algorithm using information readily available in administrative databases.

METHODS

Patients 6 to 64 years of age with asthma diagnosed from 1999-2005, who had at least one pulmonary function test, were identified from a claims database of a medical group practice located in central Massachusetts. Asthma severity for these patients was categorized using information available in an administrative database (claims-based algorithm) and by percent predicted forced expiratory volume in 1 second (FEV(1)) or peak expiratory flow (PEF) abstracted from medical charts (pulmonary function test method). Gamma rank correlation index was used to measure the association between the two severity categorization methods. Total and asthma-related healthcare costs for each severity category were compared between the two different approaches.

RESULTS

There was a significant ordinal association between severity categorization with the two classification approaches (p = 0.0002). The pulmonary function test method resulted in more frequent mild categorizations and less frequent moderate and severe categorizations than the claims-based algorithm. In only 10.9% of patients did the pulmonary function test method result in a more severe asthma category than the claims-based algorithm. Patients with more severe asthma, determined by both methods, had higher total and asthma-related health care costs. Total and asthma-related health care costs were similar for each asthma severity categorization for the two classification approaches, except for asthma-related costs in the moderate severity categories.

CONCLUSION

The claims-based algorithm generally categorized patients as having more severe asthma than the approach using pulmonary function test results. Pulmonary function test results would have appreciably changed asthma severity categorization in only a small percent of patients. These findings add further support to the use of administrative database analyses for the evaluation of asthma care in large populations.

Are sex differences in child motor activity level a function of sex differences in maturational status?

By virtue of being farther along a developmental path for motor activity level, girls may appear to be the less active sex when compared to less physically mature but same-aged boys. If so, observed sex differences in activity level may be an epiphenomenon of sex differences in maturity related declines in AL. To test this hypothesis and the associated premise that females would be more mature and less active than males, the customary activity levels and relative physical maturities of 83 5-8-year-olds were assessed. Relative maturity (percentage of estimated adult height attained) was negatively related to activity level, and girls were both less motorically active and more mature than boys. Though reduced in magnitude, the sex effect remained significant after maturity was added as a predictor of AL. Thus, sex differences are not due only to maturity differences but may be partially mediated by them.