Influence of anaerobic and aerobic exercise on age-related pathways in skeletal muscle

Predicted lean body mass trajectories, and cancer risk and cancer-specific and all-cause mortality: A prospective cohort study

BACKGROUND

Although many studies have investigated the association between body composition, cancer risk and mortality, predicting these risks through a single body composition measurement undoubtedly increases the limitations of the study. Few studies have explored the association between the trajectory of changes in body composition and the risk of cancer and death. We aimed to explore the association of predicted lean mass trajectories with cancer risk, cancer-specific mortality and all-cause mortality.

METHODS

The participants in this study were all from the Kailuan cohort, a prospective, periodic, resurvey cohort study initiated in 2006. Latent mixture modelling was used to identify predicted lean mass trajectories for 2006-2010. The hazard ratios (HRs) and 95% confidence intervals (95% CIs) of the Cox proportional hazard models were used to describe the association between predicted lean mass trajectories and cancer risk and cancer-specific and all-cause mortality during follow-up (2010-2021).

RESULTS

A total of 44 374 participants (average age, 53.01 ± 11.41 years, 78.99% men and 21.01% women) were enrolled in this study. Five distinct trajectories were identified: low-stable (n = 12 060), low-increasing (n = 8027), moderately stable-decreasing (n = 4725), moderately stable-increasing (n = 8053) and high-stable (n = 11 509). During the 11-year follow-up period, 2183 cancer events were recorded. After adjusting for age, predicted fat mass in 2010, sex, BMI, sedentary, physical activity, smoke, alcohol use, salt consumption, high-fat diet, high-sensitivity C-reactive protein, serum creatinine, family history of tumour, hypertension, diabetes mellitus, compared with the low-stable group, participants in the low-increasing group (HR = 0.851, 95% CI, 0.748-0.969), moderately stable-increasing group (HR = 0.803, 95% CI, 0.697-0.925) and high-stable group (HR = 0.770, 95% CI, 0.659-0.901) had a lower cancer risk, but not in the moderately stable-decreasing group (HR = 0.864, 95% CI, 0.735-1.015). Compared with the low-stable group, the risk of cancer-specific mortality was reduced by 25.4% (8.8-38.9%), 36.5% (20.3-49.4%) and 35.4% (17.9-49.2%), and the risk of all-cause mortality was reduced by 24.2% (16.9-30.8%), 37.0% (30.0-43.2%) and 47.4% (41.0-53.1%) in the low-increasing, moderately stable-increasing group and high-stable groups, respectively.

CONCLUSIONS

Predicted lean mass trajectories may be closely associated with cancer risk and cancer-specific and all-cause mortality. Regular monitoring of body composition is necessary.

Impact of physical activity levels on the ability to maintain static trunk posture in older adults

PROPOSE

to assess the impact of physical activity (PA) levels on sitting posture in the older adults.

METHODS

One hundred and twenty individuals were divided into three groups according their PA levels: vigorous group (VG); moderate group (MG); low group (LG). The ability to maintain static trunk posture in sitting position as assessed based on the cervical angle (CA) and thoracic angle (TA) was measured.

RESULTS

There were no significant differences between measurements in CA for the VG. However, LG and MG participants exhibited a significant decrease in CA from minute 1 to 10 and from minute 2 to 10, respectively. In the thoracic region, only the MG exhibited significant differences in TA from minute 2 to 10 compared to minute 1 (p < 0.05). No significant differences were found in TA between measurements for either VG or LG.

CONCLUSIONS

PA has a high impact on the ability to maintain static trunk posture in the older adults.

SIRT6 in Aging, Metabolism, Inflammation and Cardiovascular Diseases

As an important NAD⁺-dependent enzyme, SIRT6 has received significant attention since its discovery. In view of observations that SIRT6-deficient animals exhibit genomic instability and metabolic disorders and undergo early death, SIRT6 has long been considered a protein of longevity. Recently, growing evidence has demonstrated that SIRT6 functions as a deacetylase, mono-ADP-ribosyltransferase and long fatty deacylase and participates in a variety of cellular signaling pathways from DNA damage repair in the early stage to disease progression. In this review, we elaborate on the specific substrates and molecular mechanisms of SIRT6 in various physiological and pathological processes in detail, emphasizing its links to aging (genomic damage, telomere integrity, DNA repair), metabolism (glycolysis, gluconeogenesis, insulin secretion and lipid synthesis, lipolysis, thermogenesis), inflammation and cardiovascular diseases (atherosclerosis, cardiac hypertrophy, heart failure, ischemia-reperfusion injury). In addition, the most recent advances regarding SIRT6 modulators (agonists and inhibitors) as potential therapeutic agents for SIRT6-mediated diseases are reviewed.

Age-dependent impact of two exercise training regimens on genomic and metabolic remodeling in skeletal muscle and liver of male mice

Skeletal muscle adapts to different exercise training modalities with age; however, the impact of both variables at the systemic and tissue levels is not fully understood. Here, adult and old C57BL/6 male mice were assigned to one of three groups: sedentary, daily high-intensity intermittent training (HIIT), or moderate intensity continuous training (MICT) for 4 weeks, compatible with the older group's exercise capacity. Improvements in body composition, fasting blood glucose, and muscle strength were mostly observed in the MICT old group, while effects of HIIT training in adult and old animals was less clear. Skeletal muscle exhibited structural and functional adaptations to exercise training, as revealed by electron microscopy, OXPHOS assays, respirometry, and muscle protein biomarkers. Transcriptomics analysis of gastrocnemius muscle combined with liver and serum metabolomics unveiled an age-dependent metabolic remodeling in response to exercise training. These results support a tailored exercise prescription approach aimed at improving health and ameliorating age-associated loss of muscle strength and function in the elderly.

Exercise Therapy for People With Sarcopenic Obesity: Myokines and Adipokines as Effective Actors

Sarcopenic obesity is defined as a multifactorial disease in aging with decreased body muscle, decreased muscle strength, decreased independence, increased fat mass, due to decreased physical activity, changes in adipokines and myokines, and decreased satellite cells. People with sarcopenic obesity cause harmful changes in myokines and adipokines. These changes are due to a decrease interleukin-10 (IL-10), interleukin-15 (IL-15), insulin-like growth factor hormone (IGF-1), irisin, leukemia inhibitory factor (LIF), fibroblast growth factor-21 (FGF-21), adiponectin, and apelin. While factors such as myostatin, leptin, interleukin-6 (IL-6), interleukin-8 (IL-8), and resistin increase. The consequences of these changes are an increase in inflammatory factors, increased degradation of muscle proteins, increased fat mass, and decreased muscle tissue, which exacerbates sarcopenia obesity. In contrast, exercise, especially strength training, reverses this process, which includes increasing muscle protein synthesis, increasing myogenesis, increasing mitochondrial biogenesis, increasing brown fat, reducing white fat, reducing inflammatory factors, and reducing muscle atrophy. Since some people with chronic diseases are not able to do high-intensity strength training, exercises with blood flow restriction (BFR) are newly recommended. Numerous studies have shown that low-intensity BFR training produces the same increase in hypertrophy and muscle strength such as high-intensity strength training. Therefore, it seems that exercise interventions with BFR can be an effective way to prevent the exacerbation of sarcopenia obesity. However, due to limited studies on adipokines and exercises with BFR in people with sarcopenic obesity, more research is needed.

Body adaptation to Dance: A Gerontological Perspective

A number of studies have investigated the effectiveness of dance in older adults in the context of healthy aging. Analysing results across studies is important to understand whether dance in older adults is an effective adjunctive intervention for the healthy aging. To summarize the current research results about the effectiveness of dance in older adults in the context of healthy aging, and to identify key areas for future research. The search was conducted in Web of Science, PubMed and Google Scholar databases, using the following search string and Boolean logic (‘AND’, ‘OR’) locating studies published between database inception and September 2018: Dance OR contemporary dance OR ballroom dance OR Latin dance OR standard dance OR hip-hop dance OR tango AND Cardiovascular OR circulation AND Emotion OR well-being OR blood pressure OR disease OR thrombosis OR vascular OR glucose OR blood OR cardiac OR mental OR heart rate. Two reviewers independently extracted studies data. Eight suitable publications were included. The results showed that dance promote improvements in cognitive parameters when compared to other types of exercise or no-exercise. Significant effects were found on some physiological parameters, even after a short intervention period. Dance proved to be able to assist older adults in the context of healthy aging. The improvements in the cognitive, physiological and motor control parameters are very relevant for this population, due to the impact in a better quality of life.

Effects of Aging, Long-Term and Lifelong Exercise on the Urinary Metabolic Footprint of Rats

Life expectancy has risen in the past decades, resulting in an increase in the number of aged individuals. Exercise remains one of the most cost-effective treatments against disease and the physical consequences of aging. The purpose of this research was to investigate the effects of aging, long-term and lifelong exercise on the rat urinary metabolome. Thirty-six male Wistar rats were divided into four equal groups: exercise from 3 to 12 months of age (A), lifelong exercise from 3 to 21 months of age (B), no exercise (C), and exercise from 12 to 21 months of age (D). Exercise consisted in swimming for 20 min/day, 5 days/week. Urine samples collection was performed at 3, 12 and 21 months of life and their analysis was conducted by liquid chromatography-mass spectrometry. Multivariate analysis of the metabolite data did not show any discrimination between groups at any of the three aforementioned ages. However, multivariate analysis discriminated the three ages clearly when the groups were treated as one. Univariate analysis showed that training increased the levels of urinary amino acids and possibly protected against sarcopenia, as evidenced by the higher levels of creatine in the exercising groups. Aging was accompanied by decreased levels of urinary amino acids and signs of increased glycolysis. Concluding, both aging and, to a lesser degree, exercise affected the rat urinary metabolome, including metabolites related to energy metabolism, with exercise showing a potential to mitigate the consequences of aging.

p300 and cAMP response element-binding protein-binding protein in skeletal muscle homeostasis, contractile function, and survival

BACKGROUND

Reversible ε-amino acetylation of lysine residues regulates transcription as well as metabolic flux; however, roles for specific lysine acetyltransferases in skeletal muscle physiology and function are unknown. In this study, we investigated the role of the related acetyltransferases p300 and cAMP response element-binding protein-binding protein (CBP) in skeletal muscle transcriptional homeostasis and physiology in adult mice.

METHODS

Mice with skeletal muscle-specific and inducible knockout of p300 and CBP (PCKO) were generated by crossing mice with a tamoxifen-inducible Cre recombinase expressed under the human α-skeletal actin promoter with mice having LoxP sites flanking exon 9 of the Ep300 and Crebbp genes. Knockout of PCKO was induced at 13-15 weeks of age via oral gavage of tamoxifen for 5 days to both PCKO and littermate control [wildtype (WT)] mice. Body composition, food intake, and muscle function were assessed on day 0 (D0) through 5 (D5). Microarray and tandem mass tag mass spectrometry analyses were performed to assess global RNA and protein levels in skeletal muscle of PCKO and WT mice.

RESULTS

At D5 after initiating tamoxifen treatment, there was a reduction in body weight (-15%), food intake (-78%), stride length (-46%), and grip strength (-45%) in PCKO compared with WT mice. Additionally, ex vivo contractile function [tetanic tension (kPa)] was severely impaired in PCKO vs. WT mice at D3 (~70-80% lower) and D5 (~80-95% lower) and resulted in lethality within 1 week-a phenotype that is reversed by the presence of a single allele of either p300 or CBP. The impaired muscle function in PCKO mice was paralleled by substantial transcriptional alterations (3310 genes; false discovery rate < 0.1), especially in gene networks central to muscle contraction and structural integrity. This transcriptional uncoupling was accompanied by changes in protein expression patterns indicative of impaired muscle function, albeit to a smaller magnitude (446 proteins; fold-change > 1.25; false discovery rate < 0.1).

CONCLUSIONS

These data reveal that p300 and CBP are required for the control and maintenance of contractile function and transcriptional homeostasis in skeletal muscle and, ultimately, organism survival. By extension, modulating p300/CBP function may hold promise for the treatment of disorders characterized by impaired contractile function in humans.

Effects of lifelong exercise and aging on the blood metabolic fingerprint of rats

Regular exercise is an important part of a healthy lifestyle, as it helps maintain a healthy weight and reduces the risk of chronic diseases. We explored the effects of lifelong exercise and aging on rat metabolism through a metabolomics approach. Thirty-six rats were divided into four equal groups: exercise during the 1st half of life (3-12 months), lifelong exercise (3-21 months), no exercise, and exercise during the 2nd half of life (12-21 months). Exercise consisted in swimming for 20 min, five times a week. Blood samples collected at 3, 12, and 21 months of life were analysed by ¹H NMR spectroscopy. The groups that exercised during the 2nd half of life weighed less than the groups that did not. Exercise had an orexigenic effect during the 1st half and an anorexigenic effect during the 2nd half. Multivariate analysis showed a clear discrimination between ages when groups were treated as one and between the exercising and non-exercising groups at 12 months. Univariate analysis showed many effects of aging and some effects of exercise on metabolites involved in carbohydrate, lipid and protein metabolism. Especially during the 1st half, exercise had anabolic effects, whereas aging had catabolic effects on amino acid metabolism. In two cases (glycine and succinate), exercise (especially during the 1st half) mitigated potentially harmful effects of aging. The higher values of succinate and the lower values of lactate during the 1st half in the exercising groups suggest increased oxidative metabolism. In conclusion, moderate-intensity exercise for life or half-life had strong and potentially healthful effects on body weight and (partly) appetite, as well as on some blood metabolites. The effects of aging on the rat blood metabolome seemed to be stronger than those of exercise.

The Effect of Balance and Coordination Exercises on Quality of Life in Older Adults: A Mini-Review

The ability to control balance during activities of daily living (ADL) is impaired in older adults as a result of deterioration in the sensory systems (i.e., vestibular, visual, somatosensory), the cognitive system (central nervous system), and the musculoskeletal system. Consequently, many older adults face a risk of falling during their ADL. In most cases, falls and related injuries impair the quality of life and result in physical limitations, anxiety, loss of confidence, and fear of falling. Among a variety of fall prevention interventions, adapted physical activity programs have been suggested for improving balance control during ADL. These programs challenge the sensory, cognitive, and musculoskeletal systems while addressing balance constraints such as orientation in space, changes in direction, and the speed or height of the center of mass during static and dynamic situations resembling ADL. The above-mentioned elements can be dealt with through a combination of balance and coordination exercises that challenge the postural control systems in multiple dimensions—including vertical and horizontal changes of the center of mass, standing on unstable surfaces with a reduced base of support, and changing body directions. Consequently, such exercises require environmental information-processing. The combination of dual-task, function-oriented challenges while controlling balance stimulates the sensory and neuromuscular control mechanisms. Among older adults, these programs have been found to improve static and dynamic stability, as well as a number of aspects in the quality of life. Recently, they have also been found to improve cognitive functions such as memory and spatial cognition.

Physical Exercise Inhibits Inflammation and Microglial Activation

Accumulating evidence indicates that exercise can enhance brain function and attenuate neurodegeneration. Besides improving neuroplasticity by altering the synaptic structure and function in various brain regions, exercise also modulates multiple systems that are known to regulate neuroinflammation and glial activation. Activated microglia and several pro-inflammatory cytokines play active roles in the pathogenesis of neurodegenerative diseases, such as Alzheimer’s disease and Parkinson’s disease. The purpose of this review is to highlight the impacts of exercise on microglial activation. Possible mechanisms involved in exercise-modulated microglial activation are also discussed. Undoubtedly, more studies are needed in order to disclose the detailed mechanisms, but this approach offers therapeutic potential for improving the brain health of millions of aging people where pharmacological intervention has failed.

Healthy aging: A bibliometric analysis of the literature

Due to dramatic growth of the aging population worldwide, there has been an urgent call for a public health strategy to manage healthy aging, with the ultimate goal being advancement of aging research. Considerable progress has been made in uncovering the mystery of aging process using multidisciplinary methods. There is a growing consensus in the field that aging traits which were originally thought to be disparate are likely to be interconnected. Thus, emerging research is needed to incorporate current findings of aging by building multiscale network models. This study reported the network of healthy aging research using bibliometric approaches. Based on the results, aging of the brain and muscle is a primary research focus which is a critical part of the multiscale network regulating the aging process. Among aging-associated diseases, Alzheimer's disease and frailty are among the main research focuses, and emerging work has focused on developing diagnostic tools for these diseases. For research on anti-aging interventions, calorie restriction, physical activity, and anti-aging pharmacology are the main interventions, of which the underlying mechanisms have been comprehensively studied in animal models.

Dorsal-zone-specific reduction of sensory neuron density in the olfactory epithelium following long-term exercise or caloric restriction

Exercise (Ex) and caloric restriction (CR) reduce oxidative stress and improve organ function. For instance, voluntary Ex or CR is known to reduce age-related cochlear damage in male C57BL/6J mice. However, the effect of Ex and CR on the olfactory system is unknown. In this study, we confirmed the positive effect of Ex and CR on age-related cochlear damage, but found that Ex and CR affected negatively cell dynamics in the olfactory epithelium (OE) by reducing the number of mature olfactory sensory neurons (OSNs) and increasing the number of proliferative basal cells and apoptotic OSNs in the dorsal zone of the olfactory epithelium (OE), which contains neurons expressing NADPH quinone oxido-reductase 1 (NQO1). In addition, these interventions resulted in lower odor-induced c-fos expression in areas of the olfactory bulb receiving projections from dorsal-zone OSNs than in areas receiving ventral-zone projections. Further, we observed substantial oxidative stress in NQO1-positive cells and apoptotic OSNs in the dorsal zone in Ex and CR animals. These results suggest that, in contrast to their positive effects in other organs, Ex and CR facilitate oxidative stress and negatively impact structure and function in dorsal-zone OSNs, probably in association with NQO1 bioactivation.

Overexpression of CYB5R3 and NQO1, two NAD+ -producing enzymes, mimics aspects of caloric restriction

Calorie restriction (CR) is one of the most robust means to improve health and survival in model organisms. CR imposes a metabolic program that leads to increased stress resistance and delayed onset of chronic diseases, including cancer. In rodents, CR induces the upregulation of two NADH-dehydrogenases, namely NAD(P)H:quinone oxidoreductase 1 (Nqo1) and cytochrome b5 reductase 3 (Cyb5r3), which provide electrons for energy metabolism. It has been proposed that this upregulation may be responsible for some of the beneficial effects of CR, and defects in their activity are linked to aging and several age-associated diseases. However, it is unclear whether changes in metabolic homeostasis solely through upregulation of these NADH-dehydrogenases have a positive impact on health and survival. We generated a mouse that overexpresses both metabolic enzymes leading to phenotypes that resemble aspects of CR including a modest increase in lifespan, greater physical performance, a decrease in chronic inflammation, and, importantly, protection against carcinogenesis, one of the main hallmarks of CR. Furthermore, these animals showed an enhancement of metabolic flexibility and a significant upregulation of the NAD+ /sirtuin pathway. The results highlight the importance of these NAD+ producers for the promotion of health and extended lifespan.

In Vivo Assessment of Mitochondrial Dysfunction in Clinical Populations Using Near-Infrared Spectroscopy

The ability to sustain submaximal exercise is largely dependent on the oxidative capacity of mitochondria within skeletal muscle, and impairments in oxidative metabolism have been implicated in many neurologic and cardiovascular pathologies. Here we review studies which have demonstrated the utility of Near-infrared spectroscopy (NIRS) as a method of evaluating of skeletal muscle mitochondrial dysfunction in clinical human populations. NIRS has been previously used to noninvasively measure tissue oxygen saturation, but recent studies have demonstrated the utility of NIRS as a method of evaluating skeletal muscle oxidative capacity using post-exercise recovery kinetics of oxygen metabolism. In comparison to historical methods of measuring muscle metabolic dysfunction in vivo, NIRS provides a more versatile and economical method of evaluating mitochondrial oxidative capacity in humans. These advantages generate great potential for the clinical applicability of NIRS as a means of evaluating muscle dysfunction in clinical populations.