Physical exercise, nutrition and hormones: three pillars to fight sarcopenia

Non-Pharmacological Strategies for Managing Sarcopenia in Chronic Diseases

This article focuses on a range of non-pharmacological strategies for managing sarcopenia in chronic diseases, including exercise, dietary supplements, traditional Chinese exercise, intestinal microecology, and rehabilitation therapies for individuals with limited limb movement. By analyzing multiple studies, the article aims to summarize the available evidence to manage sarcopenia in individuals with chronic diseases. The results strongly emphasize the role of resistance training in addressing chronic diseases and secondary sarcopenia. Maintaining the appropriate frequency and intensity of resistance training can help prevent muscle atrophy and effectively reduce inflammation. Although aerobic exercise has limited ability to improve skeletal muscle mass, it does have some positive effects on physical function. Building upon this, the article explores the potential benefits of combined training approaches, highlighting their helpfulness for overall quality of life. Additionally, the article also highlights the importance of dietary supplements in combating muscle atrophy in chronic diseases. It focuses on the importance of protein intake, supplements rich in essential amino acids and omega-3, as well as sufficient vitamin D to prevent muscle atrophy. Combining exercise with dietary supplements appears to be an effective strategy for preventing sarcopenia, although the optimal dosage and type of supplement remain unclear. Furthermore, the article explores the potential benefits of intestinal microecology in sarcopenia. Probiotics, prebiotics, and bacterial products are suggested as new treatment options for sarcopenia. Additionally, emerging therapies such as whole body vibration training, blood flow restriction, and electrical stimulation show promise in treating sarcopenia with limited limb movement. Overall, this article provides valuable insights into non-pharmacological strategies for managing sarcopenia in individuals with chronic diseases. It emphasizes the importance of a holistic and integrated approach that incorporates exercise, nutrition, and multidisciplinary interventions, which have the potential to promote health in the elderly population. Future research should prioritize high-quality randomized controlled trials and utilize wearable devices, smartphone applications, and other advanced surveillance methods to investigate the most effective intervention strategies for sarcopenia associated with different chronic diseases.

Mitochondrial involvement in sarcopenia

Sarcopenia lowers the quality-of-life for millions of people across the world, as accelerated loss of skeletal muscle mass and function contributes to both age- and disease-related frailty. Physical activity remains the only proven therapy for sarcopenia to date, but alternatives are much sought after to manage this progressive muscle disorder in individuals who are unable to exercise. Mitochondria have been widely implicated in the etiology of sarcopenia and are increasingly suggested as attractive therapeutic targets to help restore the perturbed balance between protein synthesis and breakdown that underpins skeletal muscle atrophy. Reviewing current literature, we note that mitochondrial bioenergetic changes in sarcopenia are generally interpreted as intrinsic dysfunction that renders muscle cells incapable of making sufficient ATP to fuel protein synthesis. Based on the reported mitochondrial effects of therapeutic interventions, however, we argue that the observed bioenergetic changes may instead reflect an adaptation to pathologically decreased energy expenditure in sarcopenic muscle. Discrimination between these mechanistic possibilities will be crucial for improving the management of sarcopenia.

The Relationship Between Sarcopenia And Proteinuria, What Do We Know?

Sarcopenia is one of the most common geriatric syndromes in the elderly. It is defined as a decrease in muscle mass and function, and it can lead to physical disability, falls, poor quality of life, impaired immune system, and death. It is known that, the frequency of sarcopenia increases in the kidney patient population compared to healthy individuals. Although it is known that kidney disease can lead to sarcopenia; our knowledge of whether sarcopenia causes kidney disease is limited. Prior studies have suggested that protein energy wasting may be a risk of de novo CKD. Proteinuria is an important manifestation of kidney disease and there is a relationship between sarcopenia and proteinuria in diabetes, geriatric population, kidney transplant, and nephrotic syndrome. Does proteinuria cause sarcopenia or vice versa? Are they both the results of common mechanisms? This issue is not clearly known. In this review, we examined the relationship between sarcopenia and proteinuria in the light of other studies.

Prevalence of sarcopenia and its association with diet and physical activity in older adults with type 2 diabetes: A cross-sectional study

This cross-sectional study explored the prevalence of sarcopenia in older adults with type 2 diabetes and investigated the effects of diet and physical activity on sarcopenia. In total, 577 older adults with diabetes were recruited from a teaching hospital in Taiwan. Diet and physical activity were assessed using self-rated questionnaires, including the Healthy Diet Inventory, the Mini Nutritional Assessment-Short Form, and the International Physical Activity Questionnaire-Short Form. Sarcopenia was defined in accordance with the Asian Working Group for Sarcopenia 2019 guidelines. In total, 51.12% of participants had either possible sarcopenia, sarcopenia, or severe sarcopenia. Participants who were female, old age, prolonged sedentary times, poor nutritional status, and lower level of moderate-to-vigorous physical activity were identified as risk factors for possible to severe sarcopenia. Older adults with diabetes and possible to severe sarcopenia had poor nutrition status and engaged in inadequate physical activity. The findings indicate that sarcopenia may be related to nutrition status and physical activity, especially in older adults with diabetes.

Sarcopenia with Depression Presents a More Severe Disability Than Only Sarcopenia among Japanese Older Adults in Need of Long-Term Care

Background and objectives: The combination of depression and sarcopenia, a condition prevalent worldwide, may cause dis-tinct problems that should not be underestimated. However, to the best of our knowledge, no reports have investigated the combined effects of depression and sarcopenia. In this study, we compared physical function, nutritional status, and daily functioning among older adults with only depression (OD), those with only sarcopenia (OS), and those with sarcopenia with depression (SD) to examine the effects of the combination of depression and sarcopenia. Materials and Methods: The participants were 186 communi-ty-dwelling older individuals who required support or care. The participants were classified into four groups based on the presence or absence of sarcopenia and depression: Control, OD, OS, and SD. The following parameters were evaluated in the four groups: grip strength, walking speed, skeletal muscle mass index (SMI), Mini Nutritional Assessment Short-Form (MNA-sf), and long-term care certification level. In addition, univariate and multivariate analyses of the survey results were performed to identify risk factors leading from OS to SD. Results: We found that 31.2% of older participants who needed support or nursing care had SD, which had more pronounced adverse effects on grip strength, walking speed, SMI, MNA-sf, and level of nursing care than OD or OS. Furthermore, multivariate analysis of SD vs. OS showed that decreased grip strength and worsening MNA-sf were independent risk factors. Conclusions: SD is common among older individuals living in the community. Patients with SD require support and care, and the condition has a greater impact on physical function, nutritional status, and decline in life function compared to OD and OS. Therefore, it is desirable to elucidate the process leading to SD and investigate the risk factors and prognosis. It is expected that sarcopenia with depression will be investigated worldwide in the future.

Value of neutrophil-to-lymphocyte ratio for diagnosing sarcopenia in patients undergoing maintenance hemodialysis and efficacy of Baduanjin exercise combined with nutritional support

Objective

To investigate the value of neutrophil-to-lymphocyte ratio (NLR) for diagnosing sarcopenia in patients undergoing maintenance hemodialysis (MHD) and efficacy of Baduanjin exercise combined with nutritional support on MHD patients with sarcopenia.

Methods

A total of 220 patients undergoing MHD in MHD centers were selected, among which 84 had occurred with sarcopenia confirmed by measurements from the Asian Working Group for Sarcopenia. Data were collected for analyzing the influencing factors that lead to the onset of sarcopenia in MHD patients with the use of one-way analysis of variance and multivariate logistic regression. The role of NLR in the diagnosis of sarcopenia was explored, and its correlation with relevant diagnostic measurement performance such as grip strength, gait speed and skeletal muscle mass index was analyzed. In the end, some 74 patients with sarcopenia that qualify for further intervention and observation standards were divided into observation group (Baduanjin exercise plus nutritional support) and control group (nutritional support only), which were both intervened for 12 weeks. A total of 68 patients finished all interventions, with 33 patients in the observation group and 35 in the control group. The grip strength, gait speed, skeletal muscle mass index as well as the NLR were compared between the two groups.

Results

With the employment of multivariate logistic regression analysis, it was found that age, hemodialysis duration and NLR were risk factors for the onset of sarcopenia in MHD patients (P < 0.05). The area under ROC curve for NLR of MHD patients with sarcopenia was 0.695, and NLR was negatively correlated with a biochemical indicator-human blood albumin (P < 0.05). NLR was also negatively correlated with patient's grip strength, gait speed and skeletal muscle mass index, with the same correlation found in sarcopenia patients (all P < 0.05). After intervention, patient's grip strength and gait speed were both higher, and the NLR lower in the observation group than those in the control group (P < 0.05).

Conclusion

The occurrence of sarcopenia in MHD patients is associated with patient's age, hemodialysis duration and NLR. Therefore, it has been concluded that NLR has certain values in the diagnosis of sarcopenia in patients undergoing MHD. Moreover, the muscular strength can be enhanced and inflammation decreased in sarcopenia patients through nutritional support and physical exercise, i.e., Bajinduan exercise.

Muscle Strength Moderates the Relationship between Nutritional Health Risk and Depression in Korean Older Adults

Background: Little is known about the relationships between muscle strength and nutritional health risk with late-in-life depression. This study aimed to investigate the moderating effect of lower-extremity muscle strength on the relationship between nutritional health risk and depression in Korean older adults. Methods: Data obtained from 5949 women and 3971 men aged ≥ 65 years in the 2020 Korea Longitudinal Study on Aging were used in this study. Exposures included lower-extremity muscle strength and nutritional health risk. Lower-extremity muscle strength was measured with a modified sit-to-stand test. The nutritional health risk was assessed using a screening tool. Depression was defined as a score ≥ 8 points on the Geriatric Depression Scale (GDS). Results: Logistic regression analyses showed that depression was positively associated with nutritional health risk (p < 0.001) and inversely associated with lower-extremity muscle strength (p < 0.001). A moderation analysis with Andrew Hayes’ PROCESS macro showed a significant moderating effect of lower-extremity muscle strength (β = −0.119; 95% confidence interval, −0.172 to −0.066; p < 0.001) on the relationship between nutritional health risk and depression; the weaker was the muscle strength, the steeper was the slope of the GDS score for nutritional health risk. Conclusions: The current findings suggest the need for an intervention targeting both high nutritional risk and weak muscle strength as a therapeutic strategy against depression in Korean older adults.

Dyadic Satisfaction and Shared Affectivity Are Associated with Psycho-Sexual Functioning in Elderly Men and Women

Objectives The quality of sexual life of elderly people represents an understudied topic of sexual medicine and of psycho-sexology. Hence, we aimed to evaluate the association of specific psycho-relational variables, such as intimacy, increased affective gestures towards a partner (AGtP), daily shared activities, and dyadic satisfaction, with the psychosexual wellbeing of elderly people, expressed in terms of sexual satisfaction. Methods: A cohort of elderly people was selected from a sample of a broader study evaluating the role of sexual activity in protecting the emotional wellbeing of a population subjected to quarantine due to the COVID-19 pandemic. Specifically, the presence of sexual dysfunctions, the emotional wellbeing (i.e., absence of anxiety and/or depression), and the quality of the partners’ relationships were studied. For the study’s purpose, the Sexual Health Inventory for Males (SHIM), the Female Sexual Function Index (FSFI), the Orgasmometer and the Orgasmometer-F, the Generalized Anxiety Disorder scale (GAD-7), the Patient Health Questionnaire (PHQ-9), and the Dyadic Adjustment Scale were adopted. Results: A group of 124 elderly subjects (≥60) was selected for the study’s purposes. Among these, 84% were males (120/124), and 16% were females (20/124). All the subjects declared to be in a stable relationship and to be sexually active during the first lockdown period. Gender differences were found for the Dyadic Satisfaction subscale (males: 37.04 ± 6.57; females: 32.85 ± 10.04; p < 0.05) and the Orgasmometer (males: 7.64 ± 1.30; females: 6.60 ± 2.46; p < 0.01). Linear regression analysis showed the association between higher Orgasmometer scores and: (i) the absence of sexual dysfunctions (β = −1.213; SE = 0.271; p < 0.0001), (ii) higher dyadic satisfaction (β = 0.042; SE = 0.019; p < 0.05), and (iii) reduced shared activities with partner (β = −0.463; SE = 0.143; p < 0.01) and increased affective gestures towards partner (DAS measured AGtP) (β = 0.595; SE = 0.065; p < 0.0001). Post hoc analysis of ANCOVA with the Bonferroni correction method showed a significant difference in the Orgasmometer scores between subjects with and without sexual dysfunction (mean difference: 2.102; SE = 0.340; pBonf < 0.001), with healthy subjects reporting higher scores compared to dysfunctional ones. Conclusions: It is reasonable to suppose that, beyond the presence of sexual dysfunctions, the sexual health of elderly people may benefit from the quality of the relationship, and, specifically, from the presence of affective gestures towards the partner and the dyadic satisfaction. To the contrary, the quantity of time spent together, sharing specific activities, may be considered a factor worsening relational and sexual health. These data should be considered during the evaluation of sexual health among elderly people.

Exercise and Nutrition Impact on Osteoporosis and Sarcopenia-The Incidence of Osteosarcopenia: A Narrative Review

Osteoporosis and sarcopenia are diseases which affect the myoskeletal system and often occur in older adults. They are characterized by low bone density and loss of muscle mass and strength, factors which reduce the quality of life and mobility. Recently, apart from pharmaceutical interventions, many studies have focused on non-pharmaceutical approaches for the prevention of osteoporosis and sarcopenia with exercise and nutrition to being the most important and well studied of those. The purpose of the current narrative review is to describe the role of exercise and nutrition on prevention of osteoporosis and sarcopenia in older adults and to define the incidence of osteosarcopenia. Most of the publications which were included in this review show that resistance and endurance exercises prevent the development of osteoporosis and sarcopenia. Furthermore, protein and vitamin D intake, as well as a healthy diet, present a protective role against the development of the above bone diseases. However, current scientific data are not sufficient for reaching solid conclusions. Although the roles of exercise and nutrition on osteoporosis and sarcopenia seem to have been largely evaluated in literature over the recent years, most of the studies which have been conducted present high heterogeneity and small sample sizes. Therefore, they cannot reach final conclusions. In addition, osteosarcopenia seems to be caused by the effects of osteoporosis and sarcopenia on elderly. Larger meta-analyses and randomized controlled trials are needed designed based on strict inclusion criteria, in order to describe the exact role of exercise and nutrition on osteoporosis and sarcopenia.

Clarifying the relationship between sarcopenia and depression in geriatric outpatients

OBJECTIVE

We investigate the relationship between sarcopenia components and depression in geriatric outpatients, considering the effects of potential confounding factors.

METHODS

Adults ≥60 years of age were selected from outpatient clinics. Muscle strength was assessed using handgrip strength (HGS) measured using a hydraulic hand dynamometer and chair stand test (CSST). Physical performance was evaluated by usual gait speed (UGS), nutritional status, and frailty were screened by mini-nutritional assessment (MNA) questionnaire and FRAIL scale. Depression was diagnosed through a psychiatric interview and the administration of the Geriatric Depression Scale (GDS).

RESULTS

Participants with depression were similar to participants without depression regarding age (p = .055), education (p = .095), frailty (p = .857), and HGS scores (p = .053). The group with depression had longer CSST duration (p = .023), slower UGS (p =  .027), and more malnutrition (p = .001). Multivariate regression analysis revealed that only the malnutrition was independently associated factor with depression after adjusting for confounding factors.

CONCLUSIONS

Depression is associated with malnutrition and some components of sarcopenia in geriatric outpatients. Our results revealed that sarcopenia might be associated with depression through malnutrition. If malnutrition lasts for a long time, sarcopenia may become evident in the later stages of depression.

Effects of hormonal changes on sarcopenia in chronic kidney disease: where are we now and what can we do?

Sarcopenia or muscle wasting is a progressive and generalized skeletal muscle disorder involving the accelerated loss of muscle mass and function, often associated with muscle weakness (dynapenia) and frailty. Whereas primary sarcopenia is related to ageing, secondary sarcopenia happens independent of age in the context of chronic disease states such as chronic kidney disease (CKD). Sarcopenia has become a major focus of research and public policy debate due to its impact on patient's health-related quality of life, health-care expenditure, morbidity, and mortality. The development of sarcopenia in patients with CKD is multifactorial and it may occur independently of weight loss or cachexia including under obese sarcopenia. Hormonal imbalances can facilitate the development of sarcopenia in the general population and is a common finding in CKD. Hormones that may influence the development of sarcopenia are testosterone, growth hormone, insulin, thyroid hormones, and vitamin D. Although the relationship between free testosterone level that is low in uraemic patients and sarcopenia in CKD is not well-defined, functional improvement may be seen. Unlike testosterone, it is known that vitamin D is associated with muscle strength, muscle size, and physical performance in patients with CKD. Outcomes after vitamin D replacement therapy are still controversial. The half-life of growth hormone (GH) is prolonged in patients with CKD. Besides, IGF-1 levels are normal in patients with Stage 4 CKD-a minimal reduction is seen in the end-stage renal disease. Unresponsiveness or resistance of IGF-1 and changes in the GH/IGF-1 axis are the main causes of sarcopenia in CKD. Low serum T3 level is frequent in CKD, but the net effect on sarcopenia is not well-studied. CKD patients develop insulin resistance (IR) from the earliest period even before GFR decline begins. IR reduces glucose utilization as an energy source by hepatic gluconeogenesis, decreasing muscle glucose uptake, impairing intracellular glucose metabolism. This cascade results in muscle protein breakdown. IR and sarcopenia might also be a new pathway for targeting. Ghrelin, oestrogen, cortisol, and dehydroepiandrosterone may be other players in the setting of sarcopenia. In this review, we mainly examine the effects of hormonal changes on the occurrence of sarcopenia in patients with CKD via the available data.

The Therapeutic Intervention of Sex Steroid Hormones for Sarcopenia

Sarcopenia, characterized by the excessive loss of skeletal muscle mass, strength, and function, is associated with the overall poor muscle performance status of the elderly, and occurs more frequently in those with chronic diseases. The causes of sarcopenia are multifactorial due to the inherent relationship between muscles and molecular mechanisms, such as mitochondrial function, inflammatory pathways, and circulating hormones. Age-related changes in sex steroid hormone concentrations, including testosterone, estrogen, progesterone, and their precursors and derivatives, are an important aspect of the pathogenesis of sarcopenia. In this review, we provide an understanding of the treatment of sarcopenia through the regulation of sex steroid hormones. The potential benefits and future research emphasis of each sex steroid hormone therapeutic intervention (testosterone, SARMs, estrogen, SERMs, DHEA, and progesterone) for sarcopenia are discussed. Enhanced understanding of the role of sex steroid hormones in the treatment for sarcopenia could lead to the development of hormone therapeutic approaches in combination with specific exercise and nutrition regimens.

The Leucine Catabolite and Dietary Supplement β-Hydroxy-β-Methyl Butyrate (HMB) as an Epigenetic Regulator in Muscle Progenitor Cells

β-Hydroxy-β-Methyl Butyrate (HMB) is a natural catabolite of leucine deemed to play a role in amino acid signaling and the maintenance of lean muscle mass. Accordingly, HMB is used as a dietary supplement by sportsmen and has shown some clinical effectiveness in preventing muscle wasting in cancer and chronic lung disease, as well as in age-dependent sarcopenia. However, the molecular cascades underlying these beneficial effects are largely unknown. HMB bears a significant structural similarity with Butyrate and β-Hydroxybutyrate (βHB), two compounds recognized for important epigenetic and histone-marking activities in multiple cell types including muscle cells. We asked whether similar chromatin-modifying actions could be assigned to HMB as well. Exposure of murine C2C12 myoblasts to millimolar concentrations of HMB led to an increase in global histone acetylation, as monitored by anti-acetylated lysine immunoblotting, while preventing myotube differentiation. In these effects, HMB resembled, although with less potency, the histone deacetylase (HDAC) inhibitor Sodium Butyrate. However, initial studies did not confirm a direct inhibitory effect of HMB on HDACs in vitro. β-Hydroxybutyrate, a ketone body produced by the liver during starvation or intense exercise, has a modest effect on histone acetylation of C2C12 cells or in vitro HDAC inhibitor activities, and, unlike Butyrate and HMB, did not interfere with myotube formation in a myoblast differentiation assay. Instead, βHB dramatically increased lysine β-hydroxybutyrylation (Kbhb) of histone tails, an epigenetic mark associated with fasting responses and muscle catabolic states. However, when C2C12 cells were exposed to βHB in the presence of equimolar HMB this chromatin modification was drastically reduced, pointing to a role for HMB in attenuating ketosis-associated muscle wasting. In conclusion, while their mechanistic underpinnings remain to be clarified, these preliminary observations highlight novel and potentially important activities of HMB as an epigenetic regulator and βHB antagonist in muscle precursor cells, to be further explored in their biomedical implications.

Movement as a Positive Modulator of Aging

The aging of human populations, including those in Europe, is an indisputable fact. The challenge for the future is not simply prolonging human life at any cost or by any means but rather extending self-sufficiency and quality of life. Even in the most advanced societies, the eternal questions remain. Who will take care of the older generations? Will adult children’s own circumstances be sufficient to support family members as they age? For a range of complex reasons, including socioeconomic conditions, adult children are often unable or unwilling to assume responsibility for the care of older family members. For this reason, it is imperative that aging adults maintain their independence and self-care for as long as possible. Movement is an important part of self-sufficiency. Moreover, movement has been shown to improve patients’ clinical status. At a time when the coronavirus pandemic is disrupting the world, older people are among the most vulnerable. Our paper explores current knowledge and offers insights into the significant benefits of movement for the elderly, including improved immunity. We discuss the biochemical processes of aging and the counteractive effects of exercise and endogenous substances, such as vitamin D.

Age above 70 years and Charlson Comorbidity Index higher than 3 are associated with reduced survival probabilities after radical cystectomy for bladder cancer. Data from a contemporary series of 334 consecutive patients

OBJECTIVE

To assess the joint effect of age and comorbidities on clinical outcomes of radical cystectomy (RC).

METHODS

334 consecutive patients undergoing open RC for bladder cancer (BC) during the years 2005-2015 were analyzed. Pre-, peri- and post-operative parameters, including age at RC (ARC) and Charlson Comorbidity Index (CCI), were evaluated. Overall and cancer-specific survivals (OS, CSS) were assessed by univariate and multivariate modelling. Furthermore, a three-knot restricted cubic spline (RCS) was fitted to survival data to detect dependency between death-rate ratio (HR) and ARC.

RESULTS

Median follow-up time was 3.8 years (IQR = 1.3-7.5) while median OS was 5.9 years (95%CL = 3.8-9.1). Globally, 180 patients died in our cohort (53.8%), 112 of which (62.2%) from BC and 68 patients (37.8%) for unrelated causes. After adjusting for preoperative, pathological and perioperative parameters, patients with CCI > 3 showed significantly higher death rates (HR = 1.61; p = 0.022). The highest death rate was recorded in ARC = 71-76 years (HR = 2.25; p = 0.034). After fitting an RCS to both OS and CSS rates, two overlapping nonlinear trends, with common highest risk values included in ARC = 70-75 years, were observed.

CONCLUSIONS

Age over 70 years and CCI > 3 were significant factors limiting the survival of RC and should both be considered when comparing current RC outcomes.

Quadriceps muscle power and optimal shortening velocity are inversely related to angiotensin converting enzyme activity in older men

Background: Methods which potentially could prevent age-related loss of muscle mass and function are still being sought. There are various attempts to use pharmacological agents to prevent loss of muscle mass, but the effectiveness of many of them still needs to be confirmed. One of the promising therapeutics are Angiotensin Converting Enzyme Inhibitors (ACEIs) and lowering of serum ACE activity. The goal of this study was to assess if taking Angiotensin Converting Enzyme Inhibitors (ACEI) and other angiotensin system blocking medications (ASBMs) can modify muscle performance in older men as well as to assess the association of serum ACE activity with muscle strength, power, muscle contraction velocity and functional performance. Methods: Seventy-nine older men took part in the study. Muscle function was assessed with hand grip strength, maximum power relative to body mass (Pmax) and optimal shortening velocity (Ʋopt) of the knee extensor muscles. Anthropometric data, ACE activity and functional performance were also measured. Results: Negative correlations between ACE activity and Pmax (rho=-0.29, p=0.04) as well as Ʋopt  (rho=-0.31, p=0.03) in a group of patients not taking ACEI and between ACE activity and Ʋopt (rho=-0.22, p=0.05) in the whole group of men were found. Positive relationship between age and ACE activity was demonstrated (rho=0.26, p=0.02). Age was the only selected variable in the multiple regression analyses to determine both Pmax and Ʋopt. Conclusions: Serum ACE activity negatively associates to muscle power and muscle contraction velocity. The issues related to the impact of taking ACEI on the maintenance of muscle function and functional performance in older man require further studies.

Quadriceps muscle power and optimal shortening velocity are inversely related to angiotensin converting enzyme activity in older men

Background: Methods which potentially could prevent age-related loss of muscle mass and function are still being sought. There are various attempts to use pharmacological agents to prevent loss of muscle mass, but the effectiveness of many of them still needs to be confirmed. One of the promising therapeutics are Angiotensin Converting Enzyme Inhibitors (ACEIs) and lowering of serum ACE activity. The goal of this study was to assess if taking Angiotensin Converting Enzyme Inhibitors (ACEI) and other angiotensin system blocking medications (ASBMs) can modify muscle performance in older men as well as to assess the association of serum ACE activity with muscle strength, power, muscle contraction velocity and functional performance. Methods: Seventy-nine older men took part in the study. Muscle function was assessed with hand grip strength, maximum power relative to body mass (Pmax) and optimal shortening velocity (Ʋopt) of the knee extensor muscles. Anthropometric data, ACE activity and functional performance were also measured. Results: Negative correlations between ACE activity and Pmax (rho=-0.29, p=0.04) as well as Ʋopt  (rho=-0.31, p=0.03) in a group of patients not taking ACEI and between ACE activity and Ʋopt (rho=-0.22, p=0.05) in the whole group of men were found. Positive relationship between age and ACE activity was demonstrated (rho=0.26, p=0.02). Age was the only selected variable in the multiple regression analyses to determine both Pmax and Ʋopt. Conclusions: Taking ACEI is not associated with a functional performance in older men of the same age and with the same anthropometric parameters. Serum ACE activity negatively associates to muscle power and muscle contraction velocity.

The endocrinology of sarcopenia and frailty

Sarcopenia describes low muscle mass and strength associated with ageing, whilst reduced physical performance indicates the severity of the condition. It can happen independently of other medical conditions and can be a key feature of the frailty phenotype. Frailty is a syndrome of increased vulnerability to incomplete resolution of homeostasis, following a stressor event. Researchers have described the implications of hypothalamic pituitary dysregulation in the pathogenesis of both entities. This review summarizes the recent evidence in this area as well as other endocrine factors such as insulin resistance and vitamin D status and outlines current research priorities. We conducted searches to PubMed and Embase databases for articles, reviews and studies reporting new data on the interaction between hormones of the endocrine system and frailty and/ or sarcopenia in the last 5 years. Interventional studies, cohort studies, case-control studies and animal studies were included. Clinical trials register was also searched to identify ongoing relevant studies. Studies have given us insights into the complex relationships between factors such as anabolic hormones, glucocorticoids and vitamin D on muscle strength and performance and their involvement in ageing phenotypes. However, robust randomized controlled trials are needed to consolidate existing evidence in humans and inform clinical practice. Current evidence supports hormone replacement in patients with confirmed deficiencies, to optimize health and prevent complications. Hormone replacement has limited use for age-related conditions. Current interest is focused on muscle/bone/fat interactions and health outcomes in "sarcopenic obesity." A life-course approach to improving 'health-span' is advocated. Lifestyle factors such as nutrition and physical activity have important interactions with body composition, physical function and metabolic outcomes. Large-scale clinical trials will determine the efficacy and long-term safety of hormone supplementation in the management of sarcopenia and frailty.

Fat percentage cutoff values to define obesity and prevalence of sarcopenic obesity in community-dwelling older adults in Turkey

PURPOSE

Sarcopenic-obesity (SO) is associated with low-functional-status and mortality. Few studies evaluated the definition and prevalence of SO. We aimed to investigate the fat-percentage cut-off values for obesity and prevalences of obesity, SO in community-dwelling older adults in Turkey.

METHODS

Body-composition was measured using bioimpedance-analysis. Sarcopenia was defined by European-Working-Group-on-Sarcopenia-in-Older-People criteria. Obesity was defined by two different methods, a fat-percentile above 60th percentile (Zoico-method) or a BMI of ≥30 kg/m² (WHO-definition).

RESULTS

We enrolled 992 subjects (308 men, 684 women). Body fat-percentage thresholds for obesity were 27.3% for men and 40.7% for women according to Zoico-method. The rates of obesity were about 40% in both genders by Zoico-method; 29.2% versus 53.7% for men and women by WHO definition. Prevalences-of-sarcopenia was 3.1% versus 0.4%; SO was 0.3% versus 0.1% when obesity was assessed with Zoico-method in men and women, respectively. No case of SO was defined when obesity was assessed using WHO-definition.

CONCLUSION

The threshold for obesity definition according to Zoico-method was similar to other European-populations. While obesity-prevalences were considerably high, SO prevalences were low but comparable to other populations. This low-prevalence seems to be due to underestimation of sarcopenia in obese subjects when skeletal-muscle-mass was adjusted by height² to recognize low-muscle-mass.

Exercise protects proliferative muscle satellite cells against exhaustion via the Igfbp7-Akt-mTOR axis

Background and Purpose: The exhaustion of muscle satellite cells (SCs) is correlated with muscle diseases, including sarcopenia and Duchenne muscular dystrophy. Exercise benefits skeletal muscle homeostasis and promotes proliferation of SCs. Elucidating the molecular mechanism underlying the muscle function-improving effect of exercise has important implications in regenerative medicine.

Methods: Herein, we investigated the effect of 4-week treadmill training on skeletal muscle and SCs in mice. Hematoxylin and eosin (HE) staining was utilized to detect the morphometry of skeletal muscles. Flow cytometry and immunofluorescence were conducted to analyze the abundance and cell cycle of SCs. RNA sequencing was performed to elucidate the transcriptional regulatory network of SCs. The ChIP-PCR assay was used to detect enrichment of H3K27ac at the promoters of Akt.

Results: We observed that exercise resulted in muscle hypertrophy and improved muscle regeneration in mice. Unexpectedly, exercise promoted cell cycling but suppressed the Akt-mTOR pathway in SCs. Proliferative SCs in “exercised mice” required suppressed mTOR activity to limit mitochondrial metabolism, maintaining the “limited activation status” of SCs against exhaustion. Mechanistically, exercise upregulated the expression of Igfbp7, thereby impeding the phosphorylation of Akt and resulting in inhibited mTOR activity and limited mitochondrial metabolism. The limited mitochondrial metabolism resulted in hypoacetylation of histone 3 and reduced enrichment of H3K27ac at promoters of Akt, decreasing the transcription of Akt. Moreover, repeatedly injured mice showed a preserved SC pool and improved muscle regeneration by the suppression of Akt-mTOR signaling.

Conclusions: The findings of our study show that exercise protects proliferative SCs against exhaustion via the Igfbp7-Akt-mTOR axis. These findings establish a link between mechanical signaling, mitochondrial metabolism, epigenetic modification, and stem cell fate decisions; thus, present potential therapeutic targets for muscle diseases correlated with SC exhaustion.

Disease-Related Malnutrition and Sarcopenia as Determinants of Clinical Outcome

BACKGROUND

Disease-related malnutrition (DRM) and sarcopenia are common complications in chronic or severe disease, with a prevalence in general patient population of 20-50% and 0.1-85.4%, respectively. In many patient populations, malnutrition and sarcopenia are present in parallel and often manifest clinically through a combination of decreased nutrient intake, inflammation, and decreased body weight, along with a decrease in muscle mass, strength, and/or physical function, resulting in a clinical condition termed malnutrition-sarcopenia syndrome.

SUMMARY

DRM and sarcopenia are associated with increases in all-cause mortality, morbidity, length of hospital stay, and functional impairments (including disabilities and fractures) that lead to a loss of independence and higher costs. Different mortality rates are reported in malnourished patients and well-nourished patients after hospitalization, and higher mortality is the most common complication in patients with sarcopenia. Sarcopenia is a predictor of cancer survival in patients with gastrointestinal, respiratory, and urothelial cancer, and is also related to worse outcomes in patients with liver failure, intestinal insufficiency, and intestinal failure. Length of hospital stay has been found to be longer in DRM and sarcopenic patients in several studies. Prolonged hospitalization due to higher complication rates is often accompanied by demographic changes, resulting in higher hospital and health insurance costs. There are more frequent readmissions by patients with sarcopenia than nonsarcopenic patients. In addition, postoperative complications, duration of hospital stay, and costs increase with advancing sarcopenia stage. A significantly higher complication rate is also reported for DRM, leading to delayed mobilization, lower values in health-related quality of life and more adverse events. DRM is independently associated with poorer clinical outcomes in intensive care unit patients. Muscle dysfunction, as reflected by a decreased handgrip strength, is a well-known consequence of DRM and a good marker of immediate postoperative complications. Most of these outcomes have potential direct or indirect effects on hospital and health care costs, both for the patient and the society at large.

KEY MESSAGES

Consistent and robust data show DRM and sarcopenia are clinically relevant. They are an increasing problem with relevant medical consequences as well as socioeconomic implications.

Gut Microbiota, Muscle Mass and Function in Aging: A Focus on Physical Frailty and Sarcopenia

Human gut microbiota is able to influence the host physiology by regulating multiple processes, including nutrient absorption, inflammation, oxidative stress, immune function, and anabolic balance. Aging is associated with reduced microbiota biodiversity, increased inter-individual variability, and over-representation of pathobionts, and these phenomena may have great relevance for skeletal muscle mass and function. For this reason, the presence of a gut-muscle axis regulating the onset and progression of age-related physical frailty and sarcopenia has been recently hypothesized. In this narrative review, we summarize the studies supporting a possible association between gut microbiota-related parameters with measures of muscle mass, muscle function, and physical performance in animal models and humans. Reduced muscle mass has been associated with distinct microbiota composition and reduced fermentative capacity in mice, and the administration of probiotics or butyrate to mouse models of muscle wasting has been associated with improved muscle mass. However, no studies have targeted the human microbiome associated with sarcopenia. Limited evidence from human studies shows an association between microbiota composition, involving key taxa such as Faecalibacterium and Bifidobacterium, and grip strength. Similarly, few studies conducted on patients with parkinsonism showed a trend towards a different microbiota composition in those with reduced gait speed. No studies have assessed the association of fecal microbiota with other measures of physical performance. However, several studies, mainly with a cross-sectional design, suggest an association between microbiota composition and frailty, mostly assessed according to the deficit accumulation model. Namely, frailty was associated with reduced microbiota biodiversity, and lower representation of butyrate-producing bacteria. Therefore, we conclude that the causal link between microbiota and physical fitness is still uncertain due to the lack of targeted studies and the influence of a large number of covariates, including diet, exercise, multimorbidity, and polypharmacy, on both microbiota composition and physical function in older age. However, the relationship between gut microbiota and physical function remains a very promising area of research for the future.

Association between dietary nutrient intake and sarcopenia in the SarcoPhAge study

BACKGROUND

It has been suggested that a balanced nutritional intake may be useful in preventing or even reversing sarcopenia.

AIM

To describe cross-sectional associations between dietary nutrient intake and sarcopenia.

METHODS

Subjects recruited from the SarcoPhAge study population completed a food frequency questionnaire. The micronutrient and macronutrient intake was evaluated in both sarcopenic and non-sarcopenic participants. The Nutritional Belgian Recommendations of 2016 were used, i.e., adequate intake and estimated average requirement (EAR). For micronutrients, the prevalence of insufficient intake was estimated as the proportion of subjects whose intake was below the EAR.

RESULTS

A total of 331 subjects (mean age of 74.8 ± 5.9 years, 58.9% women) had complete data and were included in this study. Among them, 51 were diagnosed with sarcopenia (15.4%). In the fully adjusted model, analyses revealed that sarcopenic subjects consumed significantly lower amounts of two macronutrients (proteins, lipids) and five micronutrients (potassium, magnesium, phosphorus, iron, and vitamin K) than non-sarcopenic subjects (all p values < 0.005). A significantly increased prevalence of insufficiency was found for sarcopenic subjects compared to non-sarcopenic subjects for potassium, magnesium, iron, calcium and vitamins E and C (all p values < 0.005). The prevalence of sarcopenic subjects who were also below the Nutritional Belgian Recommendations for protein and lipids was significantly higher than that of non-sarcopenic subjects.

DISCUSSION AND CONCLUSIONS

Sarcopenic subjects seem to consume significantly reduced amounts of many micronutrients and macronutrients compared to non-sarcopenic subjects. These results suggest that a poorly balanced diet may be associated with sarcopenia and poor musculoskeletal health, although prospective studies are needed to confirm these findings.

Gender in Endocrine Diseases: Role of Sex Gonadal Hormones

Gender- and sex- related differences represent a new frontier towards patient-tailored medicine, taking into account that theoretically every medical specialty can be influenced by both of them. Sex hormones define the differences between males and females, and the different endocrine environment promoted by estrogens, progesterone, testosterone, and their precursors might influence both human physiology and pathophysiology. With the term Gender we refer, instead, to behaviors, roles, expectations, and activities carried out by the individual in society. In other words, "gender" refers to a sociocultural sphere of the individual, whereas "sex" only defines the biological sex. In the last decade, increasing attention has been paid to understand the influence that gender can have on both the human physiology and pathogenesis of diseases. Even the clinical response to therapy may be influenced by sex hormones and gender, but further research is needed to investigate and clarify how they can affect the human pathophysiology. The path to a tailored medicine in which every patient is able to receive early diagnosis, risk assessments, and optimal treatments cannot exclude the importance of gender. In this review, we have focused our attention on the involvement of sex hormones and gender on different endocrine diseases.