Adipose-Muscle crosstalk in age-related metabolic disorders: The emerging roles of adipo-myokines

The Impact of Exercise on Interleukin-6 to Counteract Immunosenescence: Methodological Quality and Overview of Systematic Reviews

OBJECTIVE

This study evaluated the methodological quality of published systematic reviews on randomized and non-randomized clinical trials to synthesize evidence on the association between IL-6, immunosenescence, and aerobic and/or resistance exercise.

METHOD

The Preferred Reporting Items for Overviews of Systematic Reviews (PRIO-harms) guideline was used, with registration number CRD42022346142-PROSPERO. Relevant databases such as Cochrane Library, PubMed, Web of Science, Scopus, and Google Scholar were searched using English Medical Subject Headings terms. Inclusion criteria were systematic reviews analyzing aerobic exercise, resistance exercise, or a combination of both and assessing IL-6 as a biomarker of cellular immunosenescence in humans. The Measurement Tool to Assess Systematic Reviews 2 (AMSTAR-2) was employed.

RESULTS

Out of 742 identified articles, 18 were eligible, and 13 were selected for analysis. Sample sizes ranged from 249 to 1421 participants, mostly female, with ages ranging from 17 to 95 years. Aerobic exercise was the most studied type (46.15%), followed by combined exercise (38.46%) and resistance exercise (15.38%). Aerobic exercise showed a statistically significant reduction in IL-6, C-reactive protein (CRP), and tumor necrosis factor-alpha (TNF-α) levels. Among the 13 reviews analyzed using AMSTAR-2, 8 were rated as critically low quality, and 5 were classified as low quality.

CONCLUSION

Aerobic exercise has anti-inflammatory properties and the potential to modulate IL-6, CRP, and TNF-α levels in immunosenescence. However, the limited methodological quality of the analyzed systematic reviews highlights the urgent need for robust, high-quality studies to improve access to information and facilitate evidence-based decision-making in healthcare.

New advances of adiponectin in regulating obesity and related metabolic syndromes

Obesity and related metabolic syndromes have been recognized as important disease risks, in which the role of adipokines cannot be ignored. Adiponectin (ADP) is one of the key adipokines with various beneficial effects, including improving glucose and lipid metabolism, enhancing insulin sensitivity, reducing oxidative stress and inflammation, promoting ceramides degradation, and stimulating adipose tissue vascularity. Based on those, it can serve as a positive regulator in many metabolic syndromes, such as type 2 diabetes (T2D), cardiovascular diseases, non-alcoholic fatty liver disease (NAFLD), sarcopenia, neurodegenerative diseases, and certain cancers. Therefore, a promising therapeutic approach for treating various metabolic diseases may involve elevating ADP levels or activating ADP receptors. The modulation of ADP genes, multimerization, and secretion covers the main processes of ADP generation, providing a comprehensive orientation for the development of more appropriate therapeutic strategies. In order to have a deeper understanding of ADP, this paper will provide an all-encompassing review of ADP.

Association of Obesity and Bariatric Surgery on Hair Health

Obesity and obesity-related conditions today constitute a public health problem worldwide. Obesity is an "epidemic" chronic disorder, which is defined by the WHO as normal or excessive fat accumulation that may impair health. It is also defined for adults as a BMI that is greater than or equal to 30. The most common obesity-related diseases are type 2 diabetes mellitus, cardiovascular diseases, metabolic syndrome, chronic kidney disease, hyperlipidemia, hypertension, nonalcoholic fatty liver disease, and certain types of cancer. It has been also proven that obesity can have a negative effect on hair. It can lead to hair thinning. Patients with obesity can undergo bariatric surgery if they meet the inclusion criteria. The four common types of weight loss surgery include a duodenal switch with biliopancreatic diversion, laparoscopic adjustable gastric banding, Roux-en-Y gastric bypass, and sleeve gastrectomy. Bariatric surgery can affect skin and hair and is associated with telogen effluvium due to weight loss, microelement deficiency, anesthesia, low calorie intake, and low protein intake. Patients who undergo bariatric surgery can experience post-bariatric surgery depression. Hair loss can have a major impact on self-esteem, negatively affecting one's self-image. The purpose of this narrative review is to critically review how obesity, obesity-related diseases, and bariatric surgery affect hair health in general and the hair development cycle, and how they influence hair loss.

Physical performance and negative events in very old adults: a longitudinal study examining the ilSIRENTE cohort

BACKGROUND

Declining physical performance in old age is associated with a wide range of negative health-related outcomes. However, it is unclear which physical capabilities should be prioritized to obtain prognostic information in older adults.

AIMS

To examine the associations between the performance on several physical function tests and falls, disability, and death in a well-characterized sample of very old Italian adults.

METHODS

This was a prospective cohort study of older adults who lived in the mountain community of the Sirente geographic area in Central Italy. Physical performance was assessed using isometric handgrip strength (IHG), walking speed (WS) at a usual and fast pace, 5-time sit-to-stand test (5STS), and sit-to-stand power measures. Appendicular skeletal muscle mass was estimated from calf circumference using a validated equation. History of falls, incident falls, and disability status according to basic Activities of Daily Living (ADLs) were recorded over two years. Survival status was obtained from the participants' general practitioners and was confirmed by the National Death Registry over 10 years from enrolment. Linear, binary, and Cox regressions were performed to evaluate the association between physical performance measures and health outcomes.

RESULTS

The mean age of the 255 participants was 84.2 ± 5.1 years, and 161 (63.1%) were women. Logistic regression indicated that IHG was significantly associated with incident ADL disability, whereas specific sit-to-stand muscle power was an independent predictor of death. No significant associations were observed between physical function and falls.

CONCLUSIONS

Our findings indicate selective associations between physical function tests and the occurrence of negative events in very old adults, with poor IHG predicting disability and specific sit-to-stand muscle power being longitudinally associated with death.

Special Issue "Adipokines, Myokines, and Physical Exercise in Health and Disease 2.0"

We are pleased to present our Editorial to this Special Issue on "Adipokines, Myokines, and Physical Exercise in Health and Disease 2 [...].

Sarcolipin relates to fattening, but not sarco/endoplasmic reticulum Ca2+-ATPase uncoupling, in captive migratory gray catbirds

In order to complete their energetically demanding journeys, migratory birds undergo a suite of physiological changes to prepare for long-duration endurance flight, including hyperphagia, fat deposition, reliance on fat as a fuel source, and flight muscle hypertrophy. In mammalian muscle, SLN is a small regulatory protein which binds to sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) and uncouples Ca2+ transport from ATP hydrolysis, increasing energy consumption, heat production, and cytosolic Ca2+ transients that signal for mitochondrial biogenesis, fatigue resistance and a shift to fatty acid oxidation. Using a photoperiod manipulation of captive gray catbirds (Dumetella carolinensis), we investigated whether SLN may play a role in coordinating the development of the migratory phenotype. In response to long-day photostimulation, catbirds demonstrated migratory restlessness and significant body fat stores, alongside higher SLN transcription while SERCA2 remained constant. SLN transcription was strongly correlated with h-FABP and PGC1α transcription, as well as fat mass. However, SLN was not significantly correlated with HOAD or CD36 transcripts or measurements of SERCA activity, SR membrane Ca2+ leak, Ca2+ uptake rates, pumping efficiency or mitochondrial biogenesis. Therefore, SLN may be involved in the process of storing fat and shifting to fat as a fuel, but the mechanism of its involvement remains unclear.

High-intensity combination exercise has the highest effect on increasing serum irisin and interleukin 6 levels in women with obesity

OBJECTIVES

Lifestyle, overnutrition, socioeconomic status, environmental conditions, and genetics are factors that cause obesity. Lifestyle modification with a nonpharmacological approach based on physical exercise is the starting point in overcoming obesity. However, physical exercise with the appropriate and effective intensity for obese subjects is still debated. Therefore, this study aims to prove the effect of intensity differences with aerobic-resistance combination exercise on increasing irisin and IL-6 levels in obese women.

METHODS

A total of 32 obese women were selected as subjects and administered the interventions of low-intensity combination exercise (Q2), moderate-intensity combination exercise (Q3), and high-intensity combination exercise (Q4). ELISA was used to measure irisin and IL-6 levels in all samples. Statistical analysis used one-way ANOVA and Turkey's-Honest Significant Difference (HSD) post hoc test.

RESULTS

The mean Δ IL-6 levels in the control groups (Q1), Q2, Q3, and Q4 were 0.27 ± 2.54, 2.07 ± 2.55, 5.99 ± 6.25, and 7.98 ± 2.82 pg/mL with (p=0.015). The mean Δ irisin levels were 0.06 ± 0.81 ng/mL in Q1, 0.59 ± 0.67 ng/mL in Q2, 1.99 ± 1.65 ng/mL in Q3, 4.63 ± 3.57 ng/mL in Q4 with (p=0.001).

CONCLUSIONS

This study proved that all three types of combined exercise intensity increased myokine levels, such as irisin and IL-6. However, high-intensity combination exercise provided the most optimal improvement in myokine levels in obese women. Future studies are needed to design long-term exercise programs specifically for obese adolescent women using the findings from this study.

Adipokines in Rheumatoid Arthritis: Emerging Biomarkers and Therapeutic Targets

Rheumatoid arthritis (RA) is a chronic inflammatory disease manifested by joint involvement, extra-articular manifestations, and general symptoms. Adipose tissue, previously perceived as an inert energy storage organ, has been recognised as a significant contributor to RA pathophysiology. Adipokines modulate immune responses, inflammation, and metabolic pathways in RA. Although most adipokines have a pro-inflammatory and aggravating effect on RA, some could counteract this pathological process. The coexistence of RA and sarcopenic obesity (SO) has gained attention due to its impact on disease severity and outcomes. Sarcopenic obesity further contributes to the inflammatory milieu and metabolic disturbances. Recent research has highlighted the intricate crosstalk between adipose tissue and skeletal muscle, suggesting potential interactions between these tissues in RA. This review summarizes the roles of adipokines in RA, particularly in inflammation, immune modulation, and joint destruction. In addition, it explores the emerging role of adipomyokines, specifically irisin and myostatin, in the pathogenesis of RA and their potential as therapeutic targets. We discuss the therapeutic implications of targeting adipokines and adipomyokines in RA management and highlight the challenges and future directions for research in this field.

Metabolic diseases and healthy aging: identifying environmental and behavioral risk factors and promoting public health

Aging is a progressive and irreversible pathophysiological process that manifests as the decline in tissue and cellular functions, along with a significant increase in the risk of various aging-related diseases, including metabolic diseases. While advances in modern medicine have significantly promoted human health and extended human lifespan, metabolic diseases such as obesity and type 2 diabetes among the older adults pose a major challenge to global public health as societies age. Therefore, understanding the complex interaction between risk factors and metabolic diseases is crucial for promoting well-being and healthy aging. This review article explores the environmental and behavioral risk factors associated with metabolic diseases and their impact on healthy aging. The environment, including an obesogenic environment and exposure to environmental toxins, is strongly correlated with the rising prevalence of obesity and its comorbidities. Behavioral factors, such as diet, physical activity, smoking, alcohol consumption, and sleep patterns, significantly influence the risk of metabolic diseases throughout aging. Public health interventions targeting modifiable risk factors can effectively promote healthier lifestyles and prevent metabolic diseases. Collaboration between government agencies, healthcare providers and community organizations is essential for implementing these interventions and creating supportive environments that foster healthy aging.

The role of myokines in cancer: crosstalk between skeletal muscle and tumor

Loss of skeletal muscle mass is a primary feature of sarcopenia and cancer cachexia. In cancer patients, tumor-derived inflammatory factors promote muscle atrophy via tumor-to-muscle effects, which is closely associated with poor prognosis. During the past decade, skeletal muscle has been considered to function as an autocrine, paracrine, and endocrine organ by releasing numerous myokines. The circulating myokines can modulate pathophysiology in the other organs, as well as in the tumor microenvironment, suggesting myokines function as muscleto-tumor signaling molecules. Here, we highlight the roles of myokines in tumorigenesis, particularly in terms of crosstalk between skeletal muscle and tumor. Better understanding of tumor-to-muscle and muscle-to-tumor effects will shed light on novel strategies for the diagnosis and treatment of cancer. [BMB Reports 2023; 56(7): 365-373].

The role of myokines in cancer: crosstalk between skeletal muscle and tumor

Loss of skeletal muscle mass is a primary feature of sarcopenia and cancer cachexia. In cancer patients, tumor-derived inflammatory factors promote muscle atrophy via tumor-to-muscle effects, which is closely associated with poor prognosis. During the past decade, skeletal muscle has been considered to function as an autocrine, paracrine, and endocrine organ by releasing numerous myokines. The circulating myokines can modulate pathophysiology in the other organs, as well as in the tumor microenvironment, suggesting myokines function as muscleto-tumor signaling molecules. Here, we highlight the roles of myokines in tumorigenesis, particularly in terms of crosstalk between skeletal muscle and tumor. Better understanding of tumor-to-muscle and muscle-to-tumor effects will shed light on novel strategies for the diagnosis and treatment of cancer. [BMB Reports 2023; 56(7): 365-373].

Sclerostin decreases in regular swimmers after ice swimming and is associated with meteorin-like protein serum levels

Introduction: Cold and exercise are two important stimuli affecting the secretion of osteokines and adipomyokines, which often occur simultaneously. However, few studies have investigated the changes in osteokines and adipomyokines induced by exercise during severe cold and their corresponding associations. Therefore, this study aimed to investigate the changes in sclerostin and meteorin-like (metrnl) protein before and after cold exercise (ice swimming [IS]) and observe their correlation. Methods: For this, 56 daily ice swimmers' data were included in this study. Serum sclerostin and metrnl were measured 30 min before IS and 30 min after. The fat mass, visceral fat area, fat-free mass, skeletal muscle mass, lumbar spine, and femoral neck bone mineral density of the ice swimmers were measured. Results: After IS, sclerostin exhibited significant decreases, whereas metrnl showed no significant change. In addition, the baseline level of sclerostin and the decrease in sclerostin were positively correlated with serum metrnl after adjusting for age, gender, and body composition indicators. Discussion: IS caused a significant decrease in sclerostin but did not affect metrnl. Furthermore, the associations between sclerostin and metrnl suggested a correlation between osteokines and adipomyokines; this encourages future exploration of the interconnection between bone, muscle, and fat, which will be beneficial for identifying potential common therapeutic targets for diseases such as osteoporosis, sarcopenia, and obesity.