Preoperative Exercise Training Decreases Complications of Minimally Invasive Lung Cancer Surgery- A Randomized Controlled Trial

OBJECTIVE

Limited evidence exists regarding the efficacy of preoperative exercise (PE) in reducing short-term complications after minimally invasive surgery in patients with non-small cell lung cancer (NSCLC). This study aims to investigate the impact of PE on short-term complications following minimally invasive lung resection.

METHODS

In this prospective, open-label, randomized (1:1) controlled trial at Xiangya Hospital, China (Sep 2020-Feb 2022), patients were randomly assigned to a PE group with 16-day alternate supervised exercise or a control. The primary outcome assessed was short-term postoperative complications, with a follow-up period of 30 days post-surgery.

RESULTS

A total of 124 patients were recruited (PE group n=62; control n=62). Finally, 101 patients (PE group; n=51 and control; n=50) with a median age of 56 years (interquartile range, 50-62 years) completed the study. Compared with the control, the PE group showed fewer postoperative complications (PE:3/51 vs. Control 10/50; OR [95% CI], 0.17 [0.04 to 0.86], P=0.03) and shorter hospital stays (mean difference [95% CI], -2 [-3 to -1], P=0.01). PE significantly improved depression, stress, functional capacity, and quality of life (all P<0.05) before surgery. Furthermore, PE demonstrated a significantly lower minimum blood pressure during surgery, lower increases body temperature on day 2 after surgery, neutrophil-to-lymphocyte ratio, and neutrophil count after surgery (all P<0.05). Exploratory research on lung tissue RNA sequencing (5 in each group) showed downregulation of the tumor necrosis factor signaling pathway in the PE group compared with control.

CONCLUSIONS

Preoperative exercise training decreased short-term postoperative complications in patients with NSCLC.

Preoperative diagnostic value of coronary CT angiography in acute Stanford type A aortic dissection involving the coronary arteries

AIM

To assess the diagnostic value of coronary computed tomography angiography (CCTA) in acute type A aortic dissection (ATAAD) with coronary artery involvement and to evaluate whether CCTA could provide potentially useful information for selecting the surgical method.

MATERIALS AND METHODS

Patients with ATAAD treated from January 2019 to December 2020 were reviewed retrospectively. Involvement of the coronary arteries based on CCTA findings were grouped into three major types and five subtypes. Interobserver and intraobserver diagnostic agreement for five subtypes were determined. The patients were divided into the coronary artery bypass grafting (CABG) and non-CABG groups, and the proportions of the five subtypes between the two groups were compared.

RESULTS

A total of 95 patients were enrolled in this study. Interobserver and intraobserver diagnostic agreement were both substantial in the left and right coronary arteries. Overall, the proportions of the five subtypes of coronary artery involvement were significantly different between the two groups (p<0.001). The proportion of Type A was elevated in the non-CABG group compared with the CABG group (22.6% versus 71.9%); by contrast, the proportions of Type B1 (35.5% versus 14.1%), Type B2 (19.4% versus 10.9%), Type C1 (6.5% versus 0%), and Type C2 (16.1% versus 3.1%) were elevated in the CABG group.

CONCLUSION

CCTA is reliable in evaluating coronary artery involvement by ATAAD. The present retrospective study indicated that CABG may be considered if the intimal flap disrupts the coronary orifice and causes luminal stenosis >50%, particularly Type B, or if an intimal tear occurs in the coronary orifice (Type C), which deserve further validation through prospective studies.

Cardiorespiratory fitness and morbidity and mortality in patients with non-small cell lung cancer: a prospective study with propensity score weighting

INTRODUCTION

This study aimed to investigate the association between cardiorespiratory fitness (CRF) and perioperative morbidity and long-term mortality in operable patients with early-stage non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

This prospective study included consecutive patients with early-stage NSCLC who underwent presurgical cardiopulmonary exercise testing between November 2014 and December 2019 (registration number: ChiCTR2100048120). Logistic and Cox proportional hazards regression were applied to evaluate the correlation between CRF and perioperative complications and long-term mortality, respectively. Propensity score overlap weighting was used to adjust for the covariates. We performed sensitivity analyses to determine the stability of our results.

RESULTS

A total of 895 patients were followed for a median of 40 months [interquartile range 25]. The median age of the patients was 59 years [range 26-83], and 62.5% were male. During the study period, 156 perioperative complications and 146 deaths were observed. Low CRF was associated with a higher risk of death (62.9 versus 33.6 per 1000 person-years; weighted incidence rate difference, 29.34 [95% CI, 0.32 to 58.36] per 1000 person-years) and perioperative morbidity (241.6 versus 141.9 per 1000 surgeries; weighted incidence rate difference, 99.72 [95% CI, 34.75 to 164.70] per 1000 surgeries). A CRF of ≤ 20 ml/kg/min was significantly associated with a high risk of long-term mortality (weighted hazard ratio, 1.98 [95% CI, 1.31 to 2.98], p < 0.001) and perioperative morbidity (weighted odds ratio, 1.93 [1.28 to 2.90], p = 0.002) compared to higher CRF.

CONCLUSION

The study found that low CRF is significantly associated with increased perioperative morbidity and long-term mortality in operable patients with early-stage NSCLC.

The long-term impact of the COVID-19 pandemic on physical fitness in young adults: a historical control study

The strength of evidence regarding long-term changes to fitness resulting from the coronavirus disease 2019 (COVID-19) lockdowns is deficient. This two-site retrospective study aimed to investigate the long-term changes in physical fitness among young adults a year after the onset of the pandemic using a robust historical control. University freshmen who underwent physical fitness tests in 2019 and completed a follow-up in 2020 (study group) were included. The primary focus was to compare the current cohort with a historical control group who completed the same tests a year prior (2018). A total of 5376 individuals were recruited, of which 2239 were in the study group. Compared with the control, the study group exhibited a decrease in anaerobic fitness, with an overall difference of -0.84 (95% confidence interval [CI], [-1.33 to -0.36]); declines in aerobic fitness, with a difference of -2.25 [-3.92 to -0.57] for males and -4.28 [-4.97 to -3.59] for females; a reduced explosive fitness (-2.68 [-3.24 to -2.12]); and a decreased upper-body strength in females (-1.52 [-2.16 to -0.87]). The fitness of young adults has been considerably compromised by COVID-19 lockdowns, highlighting the importance of promoting physical activity to prevent long-term health implications.

Prognostic role of minute ventilation/carbon dioxide production slope for perioperative morbidity and long-term survival in resectable patients with nonsmall-cell lung cancer: a prospective study using propensity score overlap weighting

BACKGROUND

The role of minute ventilation/carbon dioxide production ( / CO 2 ) slope, a ventilation efficiency marker, in predicting short-term and long-term health outcomes for patients with nonsmall-cell lung cancer (NSCLC) undergoing lung resection has not been well investigated.

MATERIAL AND METHODS

This prospective cohort study consecutively enrolled NSCLC patients who underwent a presurgical cardiopulmonary exercise test from November 2014 to December 2019. The association of / CO 2 slope with relapse-free survival (RFS), overall survival (OS), and perioperative mortality was evaluated using the Cox proportional hazards and logistic models. Covariates were adjusted using propensity score overlap weighting. The optimal cut-off point of the E/ CO 2 slope was estimated using the receiver operating characteristics curve. Internal validation was completed through bootstrap resampling.

RESULTS

A cohort of 895 patients [median age (interquartile range), 59 (13) years; 62.5% male] was followed for a median of 40 (range, 1-85) months. Throughout the study, there were 247 relapses or deaths and 156 perioperative complications. The incidence rates per 1000 person-years for relapses or deaths were 108.8 and 79.6 among patients with high and low E/ CO 2 slopes, respectively [weighted incidence rate difference per 1000 person-years, 29.21 (95% CI, 7.30-51.12)]. A E/ CO 2 slope of greater than or equal to 31 was associated with shorter RFS [hazard ratio for relapse or death, 1.38 (95% CI, 1.02-1.88), P =0.04] and poorer OS [hazard ratio for death, 1.69 (1.15-2.48), P =0.02] compared to a lower / CO 2 slope. A high E/ CO 2 slope increased the risk of perioperative morbidity compared with a low E/ CO 2 slope [odds ratio, 2.32 (1.54-3.49), P <0.001].

CONCLUSIONS

In patients with operable NSCLC, a high E/ CO 2 slope was significantly associated with elevated risks of poorer RFS, OS, and perioperative morbidity.

Exercise prevents fatal stress-induced myocardial injury in obese mice

Introduction

This study aimed to explore whether aerobic exercise (AE) can prevent fatal stress-induced myocardial injury.

Methods

Thirty C57BL/6J mice were divided into either a normal diet, high-fat diet, or high-fat diet plus AE (n=10 per group). The AE protocol consisted of eight weeks of swimming. At the end of the diet and AE interventions, the mice were stimulated with fatal stress caused by exhaustive exercise (forced weight-loaded swimming until exhaustion), after which cardiac function was evaluated using echocardiography, myocardial ultrastructure was examined using transmission electron microscopy, and myocardial apoptosis was assessed using western blotting and TUNEL. Mitophagy, mitochondrial biogenesis and dynamics, and activation of the macrophage migration inhibitor factor (MIF)/AMP-activated protein kinase (AMPK) pathway were evaluated using quantitative PCR and western blotting. Obesity phenotypes were assessed once per week.

Results

AE reversed high-fat diet-induced obesity as evidenced by reductions in body weight and visceral fat compared to obese mice without AE. Obesity exacerbated fatal stress-induced myocardial damage, as demonstrated by impaired left ventricular ejection fraction and myocardial structure. The apoptotic rate was also elevated upon fatal stress, and AE ameliorated this damage. Obesity suppressed mitophagy, mitochondrial fission and fusion, and mitochondrial biogenesis, and these effects were accompanied by suppression of the MIF/AMPK pathway in the myocardium of mice subjected to fatal stress. AE alleviated or reversed these effects.

Conclusion

This study provides evidence that AE ameliorated fatal stress-induced myocardial injury in obese mice. The cardioprotective effect of AE in obese mice might be attributed to improved mitochondrial quality.

Intermittent fasting activates macrophage migration inhibitory factor and alleviates high-fat diet-induced nonalcoholic fatty liver disease

Switching to normal diet (ND) is the regular therapy for high-fat diet (HFD)-induced nonalcoholic fatty liver disease (NAFLD). Intermittent fasting (IF) is a unique treatment which may exhibits better therapeutic efficacy. Thus, we aim to investigate the therapeutic effects of these treatments and exploring the mechanisms. In the present study, NAFLD mouse model was induced by a 10-week HFD. Thereafter, mice adopted continued HFD, ND, or IF for the next 12 weeks. Finally, the liver was then harvested to assess lipid deposition, lipid metabolism, apoptosis, and autophagy, while blood was collected to determine blood glucose and insulin. The results showed that IF and ND treatment improved lipid deposition and metabolic disorder of NAFLD mice; the increasing body weight, liver weight, and HOMA-IR index of HFD mice were also alleviated by IF and ND. Furthermore, IF and ND treatment activated the macrophage migration inhibitory factor (MIF)/AMPK pathway and regulated its downstream autophagy and apoptosis. However, the efficacy of IF was better than ND. Both IF and ND activates MIF signaling and alleviate the lipotoxicity of NAFLD while IF therapy is more effective than ND. The different MIF up-regulation might be the underlying mechanism of why IF benefits more than ND.

The Association Between a Second Course of Cardiac Rehabilitation and Cardiovascular Outcomes Following Repeat Percutaneous Coronary Intervention Events

PURPOSE

Survivors of coronary artery disease (CAD) events are at risk for repeat events. Although evidence supports cardiac rehabilitation (CR) after an initial CAD event, it is unclear whether a repeat course of CR (CR × 2) is beneficial after a recurrent CAD event. The purpose of this study was to determine the association of CR × 2 with clinical outcomes in persons undergoing repeat percutaneous coronary intervention (PCI).

METHODS

We assessed the prevalence of CR × 2 and its impact on cardiovascular outcomes in individuals who experienced a repeat PCI at the Mayo Clinic hospitals between January 1, 1998, and December 31, 2013. Landmark analyses were used to calculate unadjusted and propensity score adjusted mortality rates and cardiovascular (CV) events rates for patients who underwent CR × 2 compared with those who did not.

RESULTS

Among 240 individuals who had a repeat PCI and who had participated in CR after their first PCI, 97 (40%) participated in CR × 2. Outcomes were assessed for a mean follow-up time of 7.8 yr (IQR 7.1-9.0 yr). Propensity score-based inverse probability weighting analysis revealed that CR × 2 was associated with significantly lower target lesion revascularization (HR = 0.47: 95% CI, 0.26-0.86; P = .014), lower combined end point of CV death, myocardial infarction, and target lesion revascularization (HR = 0.57: 95% CI, 0.36-0.89; P = .014), and lower CV hospitalization (HR = 0.60; 95% CI, 0.43-0.84; P = .003).

CONCLUSION

A second course of CR following repeat PCI is associated with a lower risk of adverse clinical outcomes. These findings support current policies that allow for repeat courses of CR following recurrent CV events.

Rhodiola pre-conditioning reduces exhaustive exercise-induced myocardial injury of insulin resistant mice

Myocardial injury reduction and recovery under acute cardiac stress are adversely impacted by insulin resistance (IR). We previously demonstrated that Rhodiola improved cardiac anti-stress capacity in mice. Thus, this study focuses on the preventive efficacy of Rhodiola on exhaustive exercise (EE)-induced myocardial injury of IR mice. An 8-week high-fat diet (HFD) model of IR mice was established. Rhodiola was administrated by garaging. After the 8-week intervention, half of the mice performed EE to simulate acute cardiac stress, and determine myocardial injury; The remaining mice were sacrificed following fasting to assess metabolic disorder. We found myocardial injury induced by EE in IR mice was worse and was alleviated by Rhodiola pre-conditioning. Further, the nuclear factor erythroid 2-related factor 2 (Nrf2)-related antioxidant system was impaired by HFD, while mitochondrial dynamic fusion and fission were activated by HFD as a physiological protective compensation. The Rhodiola administration rescued Nrf2 impairment and further facilitated mitochondrial fusion and fission. All these results indicate that Rhodiola is a potential treatment for the prevention of cardiac events in type 2 diabetes mellitus and metabolic syndrome patients, and the Nrf2-related antioxidant activity and mitochondrial dynamics are the proposed mechanisms.

Rhodiola activates macrophage migration inhibitory factor to alleviate non-alcoholic fatty liver disease

AIMS

Rhodiola was found to be a potential treatment for nonalcoholic fatty liver disease (NAFLD). The macrophage migration inhibitory factor (MIF)-regulated lipophagy and lipid metabolism might be the therapeutic targets of Rhodiola.

MAIN METHODS

A 16-week high-fat diet (HFD) was used to simulate a NAFLD mouse model. Rhodiola extract or normal saline were administrated to mice. Blood was collected to assess blood glucose and insulin, and livers were harvested to assess lipid accumulation and metabolism. In cell experiments, the active ingredient of Rhodiola, salidroside, and recombinant MIF protein (rMIF) were used to treat palmitate (PA)-incubated HepG2 cells, with MIF-siRNA or NC-siRNA transfection. Then, the level of lipophagy and lipid metabolism was examined.

KEY FINDINGS

Rhodiola improved lipid accumulation and metabolism disorder of HFD mice. The oil red O staining of the liver showed that increased lipid droplets in the NAFLD liver could be relieved by Rhodiola; Rhodiola also alleviated the increasing body weight, liver weight, and HOMA-IR index of HFD mice. Results in cell experiments were consistent: salidroside relieved the lipid droplet accumulation and triglyceride release in PA cells, as well as reduced lipophagosome and lipid metabolism disorder in PA cells. However, all these effects of salidroside were partially blocked by MIF-siRNA transfection.

SIGNIFICANCE

Rhodiola reduces lipid accumulation in the liver of NAFLD by facilitating the MIF pathway and the downstream lipophagy and lipid metabolism. MIF may be an endogenous regulator of liver lipophagy and lipid metabolism and a potential therapeutic target for NAFLD.

Exercise intensity and energy expenditure of a multicomponent home-based training program: Xiangya hospital circuit training (X-CircuiT)

Introduction

Our previous studies showed that Xiangya Hospital Circuit Training (X-CircuiT) effectively improved physical fitness and reversed pre-frailty in community-dwelling older adults. This study aimed to explore the generalizability and applicability of X-CircuiT in different aged populations in the context of exercise intensity and energy expenditure.

Methods

We prospectively recruited 72 community-dwelling sedentary adults, twelve adults divided into 6 age groups ranging from 20 to 80 years old and separated by decades. Cardiopulmonary exercise testing was performed to determine peak heart rate (HR_peak). An individual HR-oxygen consumption regression equation was fit for each participant, and then a session of remote heart rate monitored X-CircuiT was performed. Exercise intensity (%HR_peak) and energy expenditure of X-CircuiT among the six age groups were assessed. Further sub-analysis was conducted by dividing the participants by peak metabolic equivalent (MET) values, <5 METs, 5–7 METs, and more than 7METs to explore the relationship between maximum exercise capacity and exercise intensity of X-CircuiT.

Results

The average %HR_peak of X-CircuiT for subjects in the 20–29, 30–39, 40–49, 50–59, 60–69, and 70–80 age groups were 54 ± 6, 59 ± 8, 60 ± 8, 62 ± 5, 66 ± 10, and 67 ± 13, respectively (p = 0.008); and the average energy expenditure was 121.9 ± 26.5, 123.3 ± 33.8, 129.2 ± 40.9, 130.9 ± 31.8, 146.8 ± 29.0, and 125.0 ± 28.4 kcal, respectively. The average %HR_peak for the warm-up, aerobic, acupoint patting, resistance, and stretching stages in overall subjects was 61 ± 9, 70 ± 10, 70 ± 10, 63 ± 9, and 57 ± 9, respectively. Furthermore, when subjects were divided by peak METs, it was found that the lower the peak METs, the greater the value of the relative exercise intensity indicators. The aerobic and acupoint stages of X-CircuiT could illicit a response of high intensity for those with peak METs <5, moderate intensity in those with peak METs of 5–7, and low-intensity for those with peak METs of more than 7.

Conclusion

Xiangya Hospital Circuit Training followed the principle of low-intensity warm-up and medium-intensity training with multicomponent exercise training. It is classified as a moderate-intensity exercise for sedentary middle-aged and older adults, or those with a maximum exercise capacity of 5–7 METs, and is classified as a low-intensity exercise for young people.

Exercise activates autophagy and regulates endoplasmic reticulum stress in muscle of high-fat diet mice to alleviate insulin resistance

Exercise training has been demonstrated as an effective therapy for insulin resistance (IR) to relieve skeletal muscle metabolic disorders. Physiologic protective autophagy was found blocked by IR induced severe endoplasmic reticulum (ER) stress, which may lead to progression of IR. However, the mechanisms are not fully understood. Therefore, this study sought to investigate that how exercise training act on IR through an exploration into the mechanism of ER stress and high-fat diet (HFD)-blocked autophagy. A rodent model was adopted in mice via a HFD and an 8-week swim exercise training intervention. The mouse IR model was successfully established through HFD treatment: body mass, adipose weight, HOMA-IR index increased, as well as IRS1, inhibited in the muscle of HFD mice. Moreover, the AMPK/PGC1α pathway was depressed and IRE1, PERK, ATF6-related ER stress signaling was activated in the muscle of HFD mice. While autophagy factors, including BNIP3, LC3II/LC3I, and PINK1, decreased. However, additional 8-week exercise training during HFD was found to reverse all these changes and alleviate IR. Thus, exercise training could facilitate HFD-blocked protective autophagy via the activation of the AMPK/PGC1α pathway to relieve insulin resistance in mice. Our study provides experimental data for the prevention of T2DM and insulin resistance.

Trimetazidine and exercise offer analogous improvements to the skeletal muscle insulin resistance of mice through Nrf2 signaling

INTRODUCTION

Insulin resistance (IR) plays a key role in the pathogenesis and clinical course of patients with multiple metabolic diseases and diabetes. This study aimed to explore the effect of trimetazidine (TMZ) on skeletal muscle IR in mice fed a high-fat diet (HFD) and explore the possible underlying mechanism.

RESEARCH DESIGN AND METHODS

In vivo, a HFD mouse IR model was adopted and TMZ and exercise were used to intervene. Postintervention the following were determined: blood levels of glucose and insulin, homeostasis model assessment of IR index, expression of skeletal muscle insulin signaling-related proteins phosphorylated insulin receptor substrate 1 (p-IRS1/IRS1) and phosphorylated protein kinase B (p-AKT/AKT), nuclear factor erythroid 2 related factor 2 (Nrf2) signaling pathway, and oxidative stress. In vitro, a palmitate-treated C2C12 myotube IR model was constructed. Cellular glucose uptake, p-IRS1/IRS1, and p-AKT/AKT were determined, and reactive oxygen species (ROS) production was analyzed based on treatments with specific small interfering RNA of Nrf2 with or without TMZ. Western blot was used to obtain the protein expression level and ROS production by functional analysis kits.

RESULTS

In vivo, TMZ and exercise decreased the blood glucose and insulin levels and homeostasis model assessment of IR index, increased skeletal muscle insulin signaling-related protein ratios of p-IRS1/IRS1 and p-AKT/AKT, and both interventions activated Nrf2 signaling and reduced oxidative stress production in HFD mice. In vitro, TMZ reduced the oxidative stress reaction, increased the ratios of p-AKT/AKT and p-IRS1/IRS1, and attenuated the insulin stimulation of PA-induced glucose uptake. However, in the absence of Nrf2, TMZ failed to resist the effects of IR.

CONCLUSIONS

This study showed that TMZ, like exercise, brought about marked improvements to HFD-induced skeletal muscle IR through TMZ, a common pathway with exercise in the form of Nrf2, regulating oxidative stress. We provide new evidence to support the use of TMZ for diabetes treatment.

Effectiveness of a multicomponent exercise program to reverse pre-frailty in community-dwelling Chinese older adults: a randomised controlled trial

BACKGROUND

the Xiangya Hospital circuit training (X-CircuiT), was developed to reverse pre-frailty in Chinese older adults and determine potential mechanisms through which pre-frailty is reversed.

METHODS

this randomised controlled trial was performed at Xiangya Hospital, Changsha, China from September 2020 to May 2021. Forty-eight pre-frail older adults were enrolled. Participants were randomly assigned (1:1) to X-CircuiT (46 min/session, three supervised sessions/week for 3 months at a community health centre) or control (1-time advice on physical activity without supervised exercise). The primary outcome was the proportion of participants with pre-frailty after 3-month intervention. The secondary outcomes included absolute risk reduction (ARR), number needed to treat (NNT), and the changes in senior fitness, body composition and clinical measures.

RESULTS

among 48 participants (mean age, 72 years; women [65%]), 22 participants in the X-CircuiT (92%) and 21 participants in the control (88%) completed the study. After 3 months, the proportion of pre-frailty was significantly lower in the X-CircuiT group than the control (14% versus 95%, P < 0.001). The ARR and NNT were 82% [95% CI, 65-99] and 1 [1-2], respectively. X-CircuiT was associated with significant improvements in senior fitness indicators and body composition. No significant difference in blood chemistry, carotid ultrasound and echocardiography parameters was found between groups. No significant interaction was detected between sex, BMI, baseline peak oxygen consumption and study groups.

CONCLUSION

this study demonstrates that X-CircuiT could significantly reverse pre-frailty in Chinese older adults. The underlying mechanisms may involve X-CircuiT-induced improvements in body composition and senior fitness.The trial is registered at Chictr.org.cn. Number: ChiCTR2100048125.

Identification of differentially expressed genes associated with coronary in-stent restenosis by integrated bioinformatics approaches

BACKGROUND

In-stent restenosis (ISR) is a common complication following percutaneous coronary intervention (PCI). Designing ISR-specific therapeutic targets is important for optimizing coronary stenosis therapy. This study aims to find new potential key genes related to ISR and the usefulness of differentially expressed genes (DEGs) as diagnostic biomarkers for ISR.

METHODS

: Microarray datasets of peripheral blood was downloaded from the Gene Expression Omnibus (GEO) public database (GSE46560, n=11). The DEGs between the ISR group and the control were obtained through the limma package analysis of the R language. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were used to obtain the related signal pathways. STRING database was used to constructed a protein-to-protein interaction network with DEGs. Networkanalyst database was used to predict the target miRNA of the target gene. The area under the curve (AUC) value obtained from receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic effectiveness of the hub gene in distinguishing ISR patients from normal individuals.

RESULTS

A total of 154 DEGs were identified between ISR group and control group, including 57 up-regulated and 97 down-regulated DEGs. GO enrichment analysis showed that genes were enriched in homeostasis, cell morphology and cell connection. KEGG pathway analysis shows that genes are mainly involved in human papillomavirus infection, salmonella infection, human T-cell leukemia virus type 1 infection, axon guidance and MAPK signaling pathway. CLTA, CAT, STAT5A, CD300A, CA1, NCF2, HBQ1, AHSP, SLC4A1 and EPB42 were identified as 10 hub genes. A total of 151 target miRNAs of 7 DEGs were obtained, and 149 mRNA-miRNA pairs were identified. ROC curve indicates that CA1, STAT5A and HBQ1 have high diagnostic value in ISR.

CONCLUSIONS

CA1, STAT5A and HBQ1 are identified as specific related genes for ISR patients. These genes may provide new targets for the early identification and treatment of ISR.

Cardiorespiratory Responses During High-Intensity Interval Training Prescribed by Rating of Perceived Exertion in Patients After Myocardial Infarction Enrolled in Early Outpatient Cardiac Rehabilitation

Objective: We aimed to determine the cardiorespiratory responses during, and adaptations to, high-intensity interval training (HIIT) prescribed using ratings of perceived exertion (RPE) in patients after myocardial infarction (MI) during early outpatient cardiac rehabilitation (CR).

Methods: We prospectively recruited 29 MI patients after percutaneous coronary intervention who began CR within 2 weeks after hospital discharge. Eleven patients (seven men; four women; age: 61 ± 11 yrs) who completed ≥24 supervised HIIT sessions with metabolic gas exchange measured during HIIT once weekly for 8 weeks and performed pre- and post- CR cardiopulmonary exercise tests were included in the study. Each HIIT session consisted of 5–8 high-intensity intervals [HIIs, 1-min RPE 14–17 (Borg 6–20 scale)] and low-intensity intervals (LIIs, 4-min RPE < 12). Metabolic gas exchange, heart rate (HR), and blood pressure during HIIT were measured.

Results: The mean oxygen uptake (V˙O₂) during HIIs across 88 sessions of HIITs [91 (14)% of V˙O_2peak, median (interquartile range, IQR)] was significantly higher than the lower limit of target V˙O₂ zone (75% of V˙O_2peak) recommended for the HII (p < 0.001). Exercise intensity during RPE-prescribed HIITs, determined as %V˙O_2peak, was highly repeatable with intra-class correlations of 0.95 (95% CI 0.86– 0.99, p < 0.001). For cardiorespiratory adaptations from the first to the last session of HIIT, treadmill speed, treadmill grade, treadmill power, V˙O_2HII, %V˙O_2peak, and V_E during HIIs were increased (all p < 0.05), while no difference was found for HR, %HR_peak and systolic blood pressure (all p > 0.05). V˙O_2peak increased by an average of 9% from pre-CR to post-CR. No adverse events occurred.

Conclusion: Our results demonstrate that HIIT can be effectively prescribed using RPE in MI patients during early outpatient CR. Participation in RPE-prescribed HIIT increases exercise workload and V˙O₂ during exercise training without increased perception of effort or excessive increases in heart rate or blood pressure.

Exercise inhibits JNK pathway activation and lipotoxicity via macrophage migration inhibitory factor in nonalcoholic fatty liver disease

The macrophage migration inhibitory factor (MIF) expressed in hepatocytes can limit steatosis during obesity. Lipotoxicity in nonalcoholic fatty liver disease is mediated in part by the activation of the stress kinase JNK, but whether MIF modulates JNK in lipotoxicity is unknown. In this study, we investigated the role of MIF in regulating JNK activation and high-fat fostered liver lipotoxicity during simultaneous exercise treatment. Fifteen mice were equally divided into three groups: normal diet, high-fat diet, and high-fat and exercise groups. High-fat feeding for extended periods elicited evident hyperlipemia, liver steatosis, and cell apoptosis in mice, with inhibited MIF and activated downstream MAPK kinase 4 phosphorylation and JNK. These effects were then reversed following prescribed swimming exercise, indicating that the advent of exercise could prevent liver lipotoxicity induced by lipid overload and might correlate to the action of modulating MIF and its downstream JNK pathway. Similar detrimental effects of lipotoxicity were observed in in vitro HepG2 cells palmitic acid treatment. Suppressed JNK reduced the hepatocyte lipotoxicity by regulating the BCL family, and the excess JNK activation could also be attenuated through MIF supplementation or exacerbated by MIF siRNA administration. The results found suggest that exercise reduces lipotoxicity and inhibits JNK activation by modulating endogenous hepatic MIF in NAFLD. These findings have clinical implications for the prevention and intervention of patients with immoderate diet evoked NAFLD.

Six-month outcomes and effect of pulmonary rehabilitation among patients hospitalized with COVID-19: a retrospective cohort study

BACKGROUND

Patients appear to maintain sequelae post-coronavirus disease 2019 (COVID-19) affecting daily life and physical health. We investigated the changes in and the effects of pulmonary rehabilitation (PR) on exercise capacity and immunology six months after COVID-19 hospitalization.

METHODS

This retrospective cohort reviewed 233 COVID-19 patients admitted from 17 January 2020 to 29 February 2020. Ninety-eight patients who completed 2-week and 6-month follow-ups and tests were included. Among 98 patients, 27 completed at least five sessions of PR at the First Hospital of Changsha, China, during the 6-month convalescence were allocated to the PR group; the reminder who had not performed any PR were assigned to the control group. The primary outcome was the change in six-minute walk distance (6-MWD) between the 2-week and 6-month follow-ups, which was assessed via analysis of covariance with a covariate of propensity score that adjusted for the potential confounders. Secondary outcomes were the changes in 6-MWD, SARS-CoV-2 immunoglobulins, T-lymphocytes and blood chemistry, which were evaluated via paired tests.

RESULTS

Participants' ages ranged from 19 to 84 years (M = 47, standard deviation (SD)=15) 45.9% identified as male. During the 6-month convalescence, 6-MWD increased 27.0%, with a mean [95% CI] of 113 [92-134] m (p < .001). SARS-CoV-2 IgG and IgM decreased 33.3% (p = .002) and 43.8% (p = .009), CD4+ T cells increased 7.9% (p = .04), and the majority of blood chemistry significantly changed. The patients in the PR group acquired a greater increase in 6-MWD than those in control (unadjusted, 194 [167-221] m, p < .001; adjusted, 123 [68-181] m, p < .001), dose-responsiveness of PR on 6-MWD was observed (p < .001). No differences in immunity variables and blood chemistry were observed between groups.

CONCLUSIONS

These findings suggest PR may be a strategy to promote the improvement of exercise capacity after COVID-19.

Screening for Asymptomatic Coronary Artery Disease via Exercise Stress Testing in Patients With Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis

Objectives: This meta-analysis aims to investigate the diagnostic value of exercise stress testing (EST) for asymptomatic coronary artery disease (CAD) among patients with type 2 diabetes mellitus (T2DM) and to ascertain the influence of different variables on the sensitivity and specificity of EST. Background: Asymptomatic CAD occurs in >1 in five diabetes mellitus patients, and it is associated with an increased risk of complications. Methods for screening asymptomatic CAD in T2DM patients are still not unified. Methods: MEDLINE (via Ovid), Embase (via Ovid), Cochrane Library, SCOPUS, PubMed, Ovid, EBSCO ASP, and Web of Science were systematically searched on June 8 and 9, 2021, for diagnostic cohort and case-control studies. We included studies that used EST to screen for CAD in asymptomatic patients with T2DM, and that used coronary angiography to diagnose CAD and had reported the basic diagnostic indicators. The Quality Assessment of Diagnostic Accuracy Studies 2 tool was used to assess study quality. The combined effect sizes were calculated by overall analysis and multiple variable effects were explored by regression analysis and subgroup analysis. Results: Nine groups of data from eight diagnostic cohort studies, totaling 515 participants, were included. Included studies showed a low risk of bias in most items, except for flow and timing. The combined sensitivity and specificity of EST for asymptomatic CAD in patients with T2DM were 55 (48 to 61%) and 66 (61 to 70%), respectively. When non-diagnostic tests were excluded, sensitivity increased to 73 (56 to 88%). The proportion receiving angiography also significantly affected sensitivity. No significant difference was found in the duration of diabetes or other additional risk factors. Conclusions: EST is a tool of moderate sensitivity and specificity to be used for the initial screening of asymptomatic CAD in T2DM. It has the advantage of being non-invasive, relatively inexpensive, easily available in most settings, and has no radiation associated with its use. Additional research with higher quality studies in which tests that are non-diagnostic are included and flow and timing is described clearly, will be important to further our understanding of EST for asymptomatic CAD detection in patients with T2DM. Systematic review registration: PROSPERO CRD42021259555.

Weight gain in Chinese youth during a 4-month COVID-19 lockdown: a retrospective observational study

OBJECTIVES

To observe the weight change in Chinese youth during a 4-month COVID-19 lockdown, and the association between weight change and mental health, physical activity and sedentary time changes, and dietary habits.

DESIGN

A retrospective observational study.

SETTINGS

Two universities located in Zhejiang and Hunan provinces, China.

PARTICIPANTS

This study enrolled 12 889 college students whose body weight was measured before the lockdown (1 December 2019-20 January 2020) at the two universities, and reported their weight measured at home or community after the end of the lockdown (1-23 May 2020) via an online follow-up questionnaire.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was the weight change in Chinese youth during a 4-month lockdown resulting from the COVID-19 pandemic. The secondary outcomes were the relationships of weight change to COVID-19-related stress, depression, anxiety, physical activity and sedentary time changes, and dietary habits.

RESULTS

Participants' ages ranged from 17 to 27 years (M=19, SD=1) with 80.2% identified as female. The average absolute and relative changes in body weight were 2.6 (95% CI 2.0 to 3.2)) kg and 4.2% (95% CI 4.0% to 4.3%) for men, and 2.1 (1.9 to 2.4) kg and 4.2% (95% CI 3.9% to 4.4%) for women. An increase in overweight and obese individuals according to Asian cut-off points as a demographic percentage by 4.5% and 2.7% and 4.8% and 3.4% in men and women, respectively (P<0.001), was observed. Weight gain was significantly associated with increased sedentary time and an increase in COVID-19-related stress and depression score.

CONCLUSION

The present study's results suggest that the risk of weight gain in Chinese youth during the lockdown increased and that strategies to decrease sedentary time and improve mental health may be warranted to mitigate weight gain during and after the COVID-19 pandemic.

The Treatment of Rhodiola Mimics Exercise to Resist High-Fat Diet-Induced Muscle Dysfunction via Sirtuin1-Dependent Mechanisms

Muscle dysfunction is a complication of high-fat diet (HFD)-induced obesity that could be prevented by exercise, but patients did not get enough therapeutic efficacy from exercise due to multiple reasons. To explore alternative or supplementary approaches to prevent or treat muscle dysfunction in individuals with obesity, we investigated the effects of Rhodiola on muscle dysfunction as exercise pills. SIRT1 might suppress atrogenes expression and improve mitochondrial quality control, which could be a therapeutic target stimulated by exercise and Rhodiola, but further mechanisms remain unclear. We verified the lipid metabolism disorders and skeletal muscle dysfunction in HFD feeding mice. Moreover, exercise and Rhodiola were used to intervene mice with a HFD. Our results showed that exercise and Rhodiola prevented muscle atrophy and dysfunction in obese mice and activating the SIRT1 pathway, while atrogenes were suppressed and mitochondrial quality control was improved. EX-527, SIRT1 inhibitor, was used to validate the essential role of SIRT1 in salidroside benefit. Results of cell culture experiment showed that salidroside alleviated high palmitate-induced atrophy and mitochondrial quality control impairments, but these improvements of salidroside were inhibited by EX-527 in C2C12 myotubes. Overall, Rhodiola mimics exercise that activates SIRT1 signaling leading to improvement of HFD-induced muscle dysfunction.

Successful Implementation and Development of a Phase II Cardiac Rehabilitation Program: A China-Wide Cross-Sectional Study Tracking In-service Training Clinical Staff

Background: Despite the benefits of cardiac rehabilitation (CR), phase II CR remains highly unavailable; the factors influential to the successful implementation and development of phase II CR programs have not been fully explored.

Methods: A cross-sectional survey was completed by 168 nationwide clinical staff. Parameters associated with the successful implementation and development of phase II CR and the factors associated with the quality of CR were explored by multivariable logistic regression.

Results: One hundred and eighteen of 168 respondents' institutions had successfully developed phase II CR programs, 41 of which delivered high-quality CR. Independent factors associated with successful implementation and development of CR were leadership support from hospital administrators, support from resident physicians, staff perception in CR increasing medical risk, and department type (cardiology vs. rehabilitation department). Independent factors associated with CR quality were the availability of “professional CR providers” and staff perceptions of CR improving physician–patient relationships. The medical system factors did not affect the development and quality of CR, including hospital level, funding type, academic type, general/specialized hospital, located city, medical insurance, the existence of a CR outpatient clinic and independent space, the availability of professional CR providers, staff structure, and the availability of regular training and standard procedure.

Conclusions: The development and quality of a phase II CR program may benefit from factors including support from administrators and resident physicians, adequately training more CR providers, without viewing medical system factors as a major issue.

The association between prior physical fitness and depression in young adults during the COVID-19 pandemic-a cross-sectional, retrospective study

Background

The COVID-19 pandemic has led to a spike in deleterious mental health. This dual-center retrospective cross-sectional study assessed the prevalence of depression in young adults during this pandemic and explored its association with various physical fitness measures.

Methods

This study enrolled 12,889 (80% female) young adults (mean age 20 ± 1) who performed a National Student Physical Fitness battery from December 1st, 2019, to January 20th, 2020, and completed a questionnaire including Beck’s Depression Inventory in May 2020. Independent associations between prior physical fitness and depression during the pandemic were assessed using multivariable linear and binary logistic regressions accordingly, covariates including age, dwelling location, economic level, smoking, alcohol, living status, weight change, and exercise volume during the pandemic. Sex- and baseline stress-stratified analyses were performed.

Results

Of the study population 13.9% of men and 15.0% of women sampled qualified for a diagnosis of depression. After multivariable adjustment, anaerobic (mean change 95% CI −3.3 [−4.8 to 1.8]) aerobic (−1.5 [−2.64 to −0.5]), explosive (−1.64 [−2.7 to −0.6]) and muscular (−1.7 [−3.0 to −0.5]) fitness were independently and inversely associated with depression for the overall population. These remained consistent after sex- and baseline stress-stratification. In binary logistic regression, the combined participants with moderate, high or excellent fitness also showed a much lower risk compared to those least fit in anaerobic (odd ratio (OR) 95% CI 0.68 [0.55–0.82]), aerobic (0.80 [0.68–0.91]), explosive (0.72 [0.61–0.82]), and muscular (0.66 [0.57–0.75]) fitness.

Conclusions

These findings suggest that prior physical fitness may be inversely associated with depression in young adults during a pandemic.

Safety of Exercise Testing in the Clinical Chinese Population

This 18-year cross-sectional study was conducted to provide data on the safety of exercise testing in the clinical Chinese population. We retrospectively identified exercise tests completed at Xiangya Hospital of Central South University from January 1, 2002 to December 31, 2019. From 43,130 unique individuals (50.9% female), a total of consecutive 50,142 tests (standard exercise testing 29,466; cardiopulmonary exercise testing 20,696) were retrieved. Demographics, patients' medical history, exercise testing characteristics, and exercise testing-related adverse events were described. Safety data is expressed as the number of adverse events per 10,000 tests, with 95% confidence interval. The average patients' age was 51 ± 13 years. The majority of patients were diagnosed with at least one disease (N = 44,941, 89.6%). Tests were maximal or symptom-limited. Common clinical symptoms included dizziness (6,822, 13.6%), chest pain or distress (2,760, 5.5%), and musculoskeletal limitations (2,507, 5.0%). Out of 50,142 tests, three adverse events occurred, including one sustained ventricular tachycardia, one sinus arrest with junctional escape rhythm at a rate of 28 bpm, and one syncopal event with fecal and urinary incontinence. The rate of adverse events was 0.8 events per 10,000 tests (95% confidence interval, 0.2–3.0) in men, 0.4 per 10,000 tests (0.7–2.2) in women, and 0.6 per 10,000 tests (0.21.8) total. This study represents the largest dataset analysis of exercise testing in the clinical Chinese population. Our results demonstrate that clinical exercise testing is safe, and the low rate of adverse events related to exercise testing might be due to the overall changes in clinical practice over time.

Exercise combined with trimetazidine improves anti-fatal stress capacity through enhancing autophagy and heat shock protein 70 of myocardium in mice

Background: Anti-stress capacity is important to resist the occurrence of adverse events. To observe the effects of exercise, trimetazidine alone or combined on the anti-stress capacity of mice, and further explore its potential mechanism. Methods: Forty-four C57BL/6 male mice aged 8 weeks were randomly divided into four groups (n=11 for each group): control group (group C), exercise group (group E), trimetazidine group (group T), exercise combined with trimetazidine group (group TE). After the intervention, each group was randomly subdivided into the exhaustive exercise (EE, n=6) and the non-EE (n=5) subgroups. The mice in the EE-subgroup underwent EE. Mice were sacrificed 12 hours later after EE. The myocardial ultrastructure and autophagosomes were observed under an electron microscope. The expression of autophagy-related proteins: BNIP3, LC3-II, and P62 were analyzed and the heat shock protein 70 mRNA transcription and protein expression were also investigated. Results: Exercise or trimetazidine increased the expression of BNIP3, LC3-II, and heat shock protein 70, decreased the expression of P62 pre- and post-EE while the combination has the synergistic effect. Conclusion: Exercise and trimetazidine, alone or combined enhanced the anti-stress capacity of mice significantly. The underlying mechanism may be associated with the promotion of autography and the expression of heat shock protein 70.

Associations of medications used during hospitalization and immunological changes in patients with COVID-19 during 3-month follow-up

BACKGROUND

Understanding the immunological responses in COVID-19 patients during their recovery period is essential to the development of a vaccine and herd immunity.

METHODS

This retrospective cohort study screened 233 patients admitted to the First Hospital of Changsha, China with COVID-19 from January 17th to February 29th, 2020. After completion of SARS-CoV2-specific immunoglobulins, and T cells tests at 2-week and 3-month follow-up points after discharge, 87 were enrolled. Wilcoxon signed-rank test was performed to assess changes in the values of IgG and IgM, the number of CD3+, CD4+ and CD8+ T cells, and CD4+/CD8+ ratio during the 3-month follow-up. Linear regressions were used to evaluate the associations of immunological changes and medications during hospitalization.

RESULTS

The positive rate of IgG decreased from 98.6% (40/41) to 85.4% (35/41) in men and 100% (43/43) to 76.7% (33/43) in women, whereas IgM declined from 34.1% (14/41) to 12.2% (5/41) in men and 37.2% (16/43) to 27.9% (12/43) in women during the follow-up. CD4+ T cells increased from (median (IQR), 484 (384-635)) cells/ul to 543 (414-657) cells/ul (P = 0.01). Antibiotic use was negatively associated with IgG change (mean change [95%CI], 8.08 [0.80-15.37] U, P = 0.03), and glucocorticoid use was positively related to increased CD4+ T cells (100.85 [16.56-185.15] cells/ul, P = 0.02).

CONCLUSION

This study demonstrated that the positive rates and values of IgG and IgM decreased in COVID-19 patients over a 3-month follow-up, while CD4+ T cells significantly increased. Moreover, we found that antibiotic use during hospitalization was associated with IgG decrease, and glucocorticoid use was associated with increases in CD4+ T cells.

Anti-insulin resistance effects of salidroside through mitochondrial quality control

Mitochondrial quality control (MQC) and function are determinants for cellular energy metabolism, and their disorders are reported to play an important role in the development of insulin resistance (IR). Salidroside was reported to have beneficial effects on MQC through AMPK pathway; however, it is unknown whether salidroside exerts anti-IR effect with this action. This study sought to investigate the effects of salidroside on IR with an exploration of the mechanisms of its action. Experimental IR models were adopted in high-fat-diet (HFD)-fed mice and palmitate-treated C2C12 myotubes, respectively. Blood levels of glucose and insulin as well as cellular glucose uptake were determined, and mitochondrial function and MQC-associated parameters and reactive oxygen species (ROS) production were analyzed based on treatments with the activator (AICAR), inhibitors (compound C and EX-527) or specific siRNA of Ampk/Sirt1 and mitochondrial ROS scavenger (mito-TEMPO). Protein expression level was determined by Western blot, cellular observation by transmission electron microscope and ROS production by functional analysis kits. Salidroside reduced IR and activated insulin signaling along with the stimulation of AMPK/SIRT1 signaling and downstream regulation of MQC and ROS production. These salidroside effects were comparable to those of AICAR and could be prevented by AMPK/SIRT1 inhibitors or siRNAs, respectively. Salidroside reduces IR and regulates MQC and ROS production by activating AMPK/SIRT1 signaling pathway. Since IR is a critical issue for public health, to explore a potent agent against IR is of high interest. The anti-IR effects of salidroside warrant further experimental and clinical studies.

High-Intensity Interval Training in Cardiac Rehabilitation: Impact on Fat Mass in Patients With Myocardial Infarction

OBJECTIVE

To examine the effect of high-intensity interval training (HIIT) on body fat mass and distribution in patients with myocardial infarction (MI) who underwent cardiac rehabilitation (CR).

PATIENTS AND METHODS

We retrospectively screened 391 consecutive patients with MI enrolled in CR between September 1, 2015, and February 28, 2018. We included 120 patients who completed 36 CR sessions and underwent pretest-posttest dual-energy x-ray absorptiometry; 90 engaged in HIIT, and 30 engaged in moderate-intensity continuous training (MICT). High-intensity interval training included 4 to 8 alternating intervals of high- (30-60 seconds at a rating of perceived exertion [RPE] of 15-17 [Borg scale range, 6-20]) and low-intensity (1-5 minutes at RPE <14), and MICT performed for 20 to 45 minutes of exercise at an RPE of 12 to 14. Body weight, fat mass, and lean mass were measured via dual-energy x-ray absorptiometry with lipid profile measured via clinical procedures.

RESULTS

The HIIT and MICT groups were similar in age (67 vs 67 years), sex (26.7% [24 of 90 patients in the HIIT group] vs 26.7% [8 of 30 in the MICT group), and body mass index (30.3 vs 29.5 kg/m²) at baseline. The HIIT group had greater reductions in body fat percentage (P<.001), fat mass (P<.001), abdominal fat percentage (P<.001), waist circumference (P=.01), total cholesterol (P=.002), low-density lipoprotein cholesterol (P<.001), and triglycerides (P=.006). Improvements in total body mass and body mass index were not different across groups. After matching exercise duration, exercise intensity, and energy expenditure, HIIT-induced improvements in total fat mass (P=.02), body fat percentage (P=.01), and abdominal fat percentage (P=.02) persisted.

CONCLUSION

Our data suggest that supervised HIIT results in significant reductions in total fat mass (P<.001) and abdominal fat percentage (P<.001) and improved lipid profile in patients with MI who undergo CR.

High-intensity interval training improves metabolic syndrome and body composition in outpatient cardiac rehabilitation patients with myocardial infarction

BACKGROUND

To examine the effect of high-intensity interval training (HIIT) on metabolic syndrome (MetS) and body composition in cardiac rehabilitation (CR) patients with myocardial infarction (MI).

METHODS

We retrospectively screened 174 consecutive patients with MetS enrolled in CR following MI between 2015 and 2018. We included 56 patients who completed 36 CR sessions and pre-post dual-energy X-ray absorptiometry. Of these patients, 42 engaged in HIIT and 14 in moderate-intensity continuous training (MICT). HIIT included 4-8 intervals of high-intensity (30-60 s at RPE 15-17 [Borg 6-20]) and low-intensity (1-5 min at RPE < 14), and MICT included 20-45 min of exercise at RPE 12-14. MetS and body composition variables were compared between MICT and HIIT groups.

RESULTS

Compared to MICT, HIIT demonstrated greater reductions in MetS (relative risk = 0.5, 95% CI 0.33-0.75, P < .001), MetS z-score (- 3.6 ± 2.9 vs. - 0.8 ± 3.8, P < .001) and improved MetS components: waist circumference (- 3 ± 5 vs. 1 ± 5 cm, P = .01), fasting blood glucose (- 25.8 ± 34.8 vs. - 3.9 ± 25.8 mg/dl, P < .001), triglycerides (- 67.8 ± 86.7 vs. - 10.4 ± 105.3 mg/dl, P < .001), and diastolic blood pressure (- 7 ± 11 vs. 0 ± 13 mmHg, P = .001). HIIT group demonstrated greater reductions in body fat mass (- 2.1 ± 2.1 vs. 0 ± 2.2 kg, P = .002), with increased body lean mass (0.9 ± 1.9 vs. - 0.9 ± 3.2 kg, P = .01) than the MICT. After matching for exercise energy expenditure, HIIT-induced improvements persisted for MetS z-score (P < .001), MetS components (P < .05), body fat mass (P = .002), body fat (P = .01), and lean mass (P = .03).

CONCLUSIONS

Our data suggest that, compared to MICT, supervised HIIT results in greater improvements in MetS and body composition in MI patients with MetS undergoing CR.

High-Intensity Interval Training in Cardiac Rehabilitation

Recently, high-intensity interval training (HIIT) has been recognized as a safe and effective alternative to moderate-intensity continuous training for older patients with cardiovascular disease (CVD) in cardiac rehabilitation settings in an effort to improve health outcomes. This brief review considers general principles and suggestions for prescription of HIIT for older patients with CVD, specific challenges pertaining to older adults, the physiologic mechanisms by which HIIT contributes to improvements in peak Vo₂, and the effects of HIIT on cardiovascular health in older patients with coronary artery disease and heart failure.

Trimetazidine combined with exercise improves exercise capacity and anti-fatal stress ability through enhancing mitochondrial quality control

AIMS

To explore the effects of trimetazidine combined with exercise on EC and anti-fatal stress ability, and illustrate the underlying mechanism.

METHODS

C57BL/6 mice were randomly assigned to four groups (n = 11 in each group): the control, exercise, trimetazidine and trimetazidine + exercise (TE) groups. Mice were accordingly given saline (ig), Aerobic exercise (AE), trimetazidine (ig), or a combination of trimetazidine (ig) and AE for five weeks. After the intervention, each group was randomly subdivided into rest and exhaustive exercise (EE) subgroups. The mice in the control-EE and TE-EE subgroups underwent fatal stress experiments. EC and anti-fatal stress ability were assessed respectively. Mitochondrial quality control (MQC) in skeletal muscle were measured at the protein level and the organelle level.

KEY FINDINGS

A significantly increased exhaustive swimming time was observed in exercise (39.10 ± 12.58 min vs 14.18 ± 4.37 min), trimetazidine (33.73 ± 8.45 min vs 14.18 ± 4.37 min) and TE groups (73.78 ± 18.95 min vs 14.18 ± 4.37 min) compared with that in the control group, and a synergistic effect was detected (P < 0.05). Fatal stress experiments successfully induced skeletal muscle damage, including increased creatine kinase activity, myofibrosis, and impaired antioxidative enzyme system, all those were significantly alleviated by trimetazidine supplementation combined with AE precondition (P < 0.05). Meanwhile, AE and trimetazidine alone or combined, significantly enhanced the MQC in normal mice by activating mitochondrial biogenesis, dynamics and mitophagy, and that in mice underwent fatal stress stimulus (P < 0.05).

SIGNIFICANCE

This study for the first time found that trimetazidine and AE have synergistic effects on improving EC. Moreover, the combination of both interventions enhances anti-fatal stress ability. Enhancing MQC may be a key mechanism of AE combined with trimetazidine that improves EC and anti-fatal stress ability.

Functional and molecular analysis of D-serine transport in retinal Müller cells

D-serine, an endogenous co-agonist of NMDA receptors in vertebrate retina, may modulate glutamate sensitivity of retinal neurons. This study determined at the functional and molecular level the transport process responsible for D-serine in retinal Müller cells. RT-PCR and immunoblotting showed that serine racemase (SR), the synthesizing enzyme for D-serine, is expressed in the rMC-1 Müller cell line and primary cultures of mouse Müller cells (1 degrees MCs). The relative contributions of different amino acid transport systems to d-serine uptake were determined based on differential substrate specificities and ion dependencies. D-serine uptake was obligatorily dependent on Na+, eliminating Na+-independent transporters (asc-1 and system L) for D-serine in Müller cells. The Na+:substrate stoichiometry for the transport process was 1:1. D-serine transport was inhibited by alanine, serine, cysteine, glutamine, and asparagine, but not anionic amino acids or cationic amino acids, suggesting that D-serine transport in Müller cells occurs via ASCT2 rather than ASCT1 or ATB0,+. The expression of mRNAs specific for ASCT1, ASCT2, and ATB0,+ was analyzed by RT-PCR confirming the expression of ASCT2 (and ASCT1) mRNA, but not ATB0,+, in Müller cells. Immunoblotting detected ASCT2 in neural retina and in 1 degrees MCs; immunohistochemistry confirmed these data in retinal sections and in cultures of 1 degrees MCs. The efflux of D-serine via ASCT2 by ASCT2 substrates was demonstrable using the Xenopus laevis oocyte heterologous expression system. These data provide the first molecular evidence for SR and ASCT2 expression in a Müller cell line and in 1 degrees MCs and suggest that D-serine, synthesized in Müller cells by SR, is effluxed via ASCT2 to regulate NMDA receptors in adjacent neurons.

Activated polymorphonuclear leukocytes induce cardiomyocyte apoptosis and the protective effects of carvedilol

Previous studies have shown that ischemia and reperfusion are potent stimuli for eliciting cardiomyocyte apoptosis, and that polymorphonuclear leukocytes (PMNs) are involved in the development of myocardial injury induced by ischemia and reperfusion. The present study examined whether PMN could directly induce cardiomyocyte apoptosis and, if so, it possible signal transduction pathways. In addition, we also investigated the effects of carvedilol, a potent antioxidant, on PMN-induced apoptosis. Cultured primary neonatal rat cardiomyocytes were exposed to PAF-activated PMNs at concentrations of 10(5), 3 x 10(5) and 10(6) cells/well for 48 h. Multiple detecting techniques, including electron microscopy, DNA gel electrophoresis. TUNEL assay and flow cytometry were used to identify myocyte apoptosis. All of these techniques demonstrated that activated PMNs directly induced cardiomyocyte apoptosis in a concentration-dependent manner, while unactivated PMNs showed no such effect. Activated PMN-induced apoptosis was partially inhibited by SB203580, a specific inhibitor of the p38-MAPK signaling system. Carvedilol (at a dose range of 1-10 mumol/l) significantly prevented activated PMN-induced cardiomyocyte apoptosis. These results suggest that PMNs, when activated, directly induce cardiomyocyte apoptosis and that the p38-MAPK signaling pathway might be involved in this process. Carvedilol may prevent PMN-induced apoptosis possibly because of its antioxidant properties.

Protective effects of nitroglycerin-induced preconditioning mediated by calcitonin gene-related peptide in rat small intestine

Previous studies of myocardium have shown that ischemic preconditioning could be mimicked by nitroglycerin through stimulating the release of calcitonin gene-related peptide (CGRP). The present study examined whether nitroglycerin could also provide a preconditioning stimulus in the peripheral vascular bed (the anse intestinalis of rat), and whether endogenous CGRP is involved in this process. The model of in situ perfusion was prepared with rat small intestine. One hour of ischemia and 15 min of reperfusion caused a significant impairment of intestinal morphology and an increase in the release of both lactate dehydrogenase and malondialdehyde. Pretreatment with nitroglycerin, 10(-7), 3 x 10(-7), 10(-6) M for 5 min produced a significant improvement of intestinal tissue morphology and a decrease in the release of both lactate dehydrogenase and malondialdehyde. However, the protection afforded by nitroglycerin was abolished by CGRP-(8-37), a selective CGRP acceptor antagonist. Pretreatment with capsaicin, which specifically depletes the transmitter content of sensory nerves, also abolished the protection by nitroglycerin. In addition, the content of CGRP-like immunoreactivity in the effluent was increased during nitroglycerin perfusion. On the other hand, the results from the in vivo experiment showed that nitroglycerin (i.v. 0.13 mg/kg) injected 5 min before prolonged ischemia could provide significant protection against the injury caused by 30-min ischemia and 1-h reperfusion in the rat small intestine, but would also cause a significant increase in the levels of CGRP in the plasma. All these findings suggest that nitroglycerin-induced preconditioning is related to stimulation of CGRP release in the rat small intestine.

Role of endogenous opioid peptides in protection of ischemic preconditioning in rat small intestine

This study investigated the protective effects of ischemic preconditioning on intestinal ischemic injury and the role of endogenous opioid peptides (EOP) in these effects. Ischemia-reperfusion (I/R) induced by 30-min of ischemia and 60-min of reperfusion significantly increased the levels of malondialdehyde (MDA) and lactate dehydrogenase (LDH) and resulted in serious intestinal edema (wet weight/dry weight). The ischemic preconditioning (PC) elicited by three 8-min occlusion periods interspersed with 10-min reperfusion markedly attenuated intestinal injury caused by ischemia-reperfusion. Pretreatment with morphine (300 microg x kg(-1), i.v.) 10-min before ischemia and reperfusion mimicked the protection produced by PC. Naloxone (3 mg x kg(-1), i.v.) abolished the protection of morphine-induced preconditioning and ischemic preconditioning in rat intestine. However, there were no changes between naloxone alone and control groups. Treatment with naloxone before ischemia-reperfusion had no effect on animals compared with the I/R group. In addition, we also measured the content of endogenous opioid peptides (Leu-enkephalin) in the effluent which was collected before and during preconditioning. It was shown that the release of leu-enkephalin was markedly increased during preconditioning. These results suggested that EOP might play an important role in PC in rat small intestine.

A comparative study of the effects of magnetic stimulation and electric stimulation on peripheral nerve injury in rat

The influence of pulsed magnetic stimulation (MS) on the sciatic nerve injury was investigated. Thirty rats were divided into three groups equally: MS group (A), electric stimulation (ES) group (B) and the control group (C). The MS and ES were applied immediately after the first 10 min of the sciatic nerve crush. Sciatic function index (SFI), toe spreading reflex (TSR), muscular weight and volume were measured after the experiment. The TSR of in the groups A and B occurred at 4th day while in the control group it occurs at 10th day. There was statistically significant difference in SFI between groups A and B (P < 0.01). The weight and volume of the gastrocnemius muscle were statistically greater in the groups A and B than in the control group (P < 0.01). The effect of MS was similar to that of ES. It was suggested that the application of MS immediately after the nerve injury might have an important clinical value as it can accelerate functional recovery and prevent or minimize muscle atrophy. The technique is easily to operate, non-invasion, painless and permits tolerance of high intensity output to be used.