Apelin as a Potential Regulator of Peak Athletic Performance

Exerkine-mediated organ interactions: A new interpretation of exercise on cardiovascular function improvement

Cardiovascular diseases impair the structure and function of distal organs, including the liver, skeletal muscle, kidney, and adipose tissue. Exercise stimulates the interaction between the cardiovascular system and distal organs that is important for disease rehabilitation and organ health. However, the mechanisms by which exercise improves cardiovascular function through exerkine-mediated organ crosstalk remain incompletely elucidated. We used cardiovascular, exercise, exerkines, skeletal muscle, liver, kidney, and adipose tissue as keywords to search for the relevant articles, sorted out the differences between different exercise types, summarized the functions of 17 exerkines, focused on reviewing and categorizing the molecular mechanisms of interactions between the cardiovascular system and remote organs. We also look forward to future research perspectives on exercise prevention and control of chronic metabolic diseases. The aim of this review is to provide a new theoretical basis for establishing clinical rehabilitation and exercise prescriptions for cardiovascular system diseases.

Circulating apelin levels fail to link sarcopenia-related muscle parameters in older adults

BACKGROUND

Based on the compelling experimental evidence supporting apelin's beneficial effects on muscle metabolism, our study aimed to evaluate the role of circulating apelin levels as a biomarker for muscle health in humans.

METHODS

This investigation employed a cross-sectional design, encompassing 237 community-dwelling older adults aged ≥65 years who underwent comprehensive geriatric evaluations in South Korea. Sarcopenia diagnosis was based on Asian-specific criteria, and serum apelin concentrations were determined using enzyme immunoassay techniques.

RESULTS

Following adjustment for potential confounding factors, no significant disparities in serum apelin levels were observed between sarcopenic and non-sarcopenic individuals, nor were differences detected based on skeletal muscle mass, strength, or physical performance categories (P = 0.335 to 0.765). Furthermore, circulating apelin concentrations showed no significant correlations with any sarcopenia assessment metrics, including skeletal muscle index, grip strength, gait speed, chair stand test duration, or short physical performance battery score (P = 0.170 to 0.832). Elevations in serum apelin levels were not significantly associated with the risk of sarcopenia or compromised muscle phenotypes (P = 0.452 to 0.896). Additionally, stratification of participants into quartiles based on serum apelin concentrations revealed no significant variations in sarcopenia-related parameters across groups (P = 0.197 to 0.592).

CONCLUSION

These findings suggest that, contrary to previous studies in cellular and animal models where apelin demonstrated a protective impact on muscle homeostasis, such effects may not translate to the human context, and contribute valuable clinical evidence indicating that serum apelin may not serve as a reliable biomarker for sarcopenia.

One Month of Brief Weekly Magnetic Field Therapy Enhances the Anticancer Potential of Female Human Sera: Randomized Double-Blind Pilot Study

Preclinical studies have shown that the blood from female mice exposed weekly to magnetic fields inhibited breast cancer growth. This double-blind randomized controlled trial investigated whether analogous magnetic therapy could produce similar anticancer sera from human subjects. Twenty-six healthy adult females (ages 30-45) were assigned to either a magnetic therapy group, receiving twice weekly 1 mT magnetic exposures (10 min/session) for 4 weeks, or a control group, who underwent identical sham exposure. Blood sera were evaluated for their capacity to modulate breast cancer-related cellular responses and epithelial-mesenchymal transition. The sera from the magnetic therapy group subjects exhibited significant anticancer effects that were strongest one month after the last magnetic exposure, whereas the sera from unexposed females or unexposed or exposed males showed no effect. Female sera from the magnetic therapy group (n = 12) reduced breast cancer cell proliferation (16.1%), migration (11.8%) and invasion (28.2%) and reduced the levels of key EMT markers relative to the control sera (n = 14). Magnetic therapy modulated the serum levels of angiogenic and myogenic biomarkers in a manner consistent with improved cancer management. Muscle-targeted magnetic therapy holds the potential to enhance the anticancer properties of human blood via an adaptive process, akin to exercise training.

Research Progress on the Effects of Different Exercise Modes on the Secretion of Exerkines After Spinal Cord Injury

Exercise training is a conventional treatment strategy throughout the entire treatment process for patients with spinal cord injury (SCI). Currently, exercise modalities for SCI patients primarily include aerobic exercise, endurance training, strength training, high-intensity interval training, and mind-body exercises. These exercises play a positive role in enhancing skeletal muscle function, inducing neuroprotection and regeneration, thereby influencing neural plasticity, reducing limb spasticity, and improving motor function and daily living abilities in SCI patients. However, the mechanism by which exercise training promotes functional recovery after SCI is still unclear, and there is no consensus on a unified and standardized exercise treatment plan. Different exercise methods may bring different benefits. After SCI, patients' physical activity levels decrease significantly due to factors such as motor dysfunction, which may be a key factor affecting changes in exerkines. The changes in exerkines of SCI patients caused by exercise training are an important and highly relevant and visual evaluation index, which may provide a new research direction for revealing the intrinsic mechanism by which exercise promotes functional recovery after SCI. Therefore, this article summarizes the changes in the expression of common exerkines (neurotrophic factors, inflammatory factors, myokines, bioactive peptides) after SCI, and intends to analyze the impact and role of different exercise methods on functional recovery after SCI from the perspective of exerkines mechanism. We hope to provide theoretical basis and data support for scientific exercise treatment programs after SCI.

The function of previously unappreciated exerkines secreted by muscle in regulation of neurodegenerative diseases

The initiation and progression of neurodegenerative diseases (NDs), distinguished by compromised nervous system integrity, profoundly disrupt the quality of life of patients, concurrently exerting a considerable strain on both the economy and the social healthcare infrastructure. Exercise has demonstrated its potential as both an effective preventive intervention and a rehabilitation approach among the emerging therapeutics targeting NDs. As the largest secretory organ, skeletal muscle possesses the capacity to secrete myokines, and these myokines can partially improve the prognosis of NDs by mediating the muscle-brain axis. Besides the well-studied exerkines, which are secreted by skeletal muscle during exercise that pivotally exert their beneficial function, the physiological function of novel exerkines, e.g., apelin, kynurenic acid (KYNA), and lactate have been underappreciated previously. Herein, this review discusses the roles of these novel exerkines and their mechanisms in regulating the progression and improvement of NDs, especially the significance of their functions in improving NDs' prognoses through exercise. Furthermore, several myokines with potential implications in ameliorating ND progression are proposed as the future direction for investigation. Elucidation of the function of exerkines secreted by skeletal muscle in the regulation of NDs advances the understanding of its pathogenesis and facilitates the development of therapeutics that intervene in these processes to cure NDs.

Exercise-Induced Blood Pressure Dynamics: Insights from the General Population and the Athletic Cohort

Blood pressure (BP) dynamics during graded exercise testing provide important insights into cardiovascular health, particularly in athletes. These measurements, taken during intense physical exertion, complement and often enhance our understanding beyond traditional resting BP measurements. Historically, the challenge has been to distinguish 'normal' from 'exaggerated' BP responses in the athletic environment. While basic guidelines have served their purpose, they may not fully account for the complex nature of BP responses in today's athletes, as illuminated by contemporary research. This review critically evaluates existing guidelines in the context of athletic performance and cardiovascular health. Through a rigorous analysis of the current literature, we highlight the multifaceted nature of exercise-induced BP fluctuations in athletes, emphasising the myriad determinants that influence these responses, from specific training regimens to inherent physiological nuances. Our aim is to advocate a tailored, athlete-centred approach to BP assessment during exercise. Such a paradigm shift is intended to set the stage for evidence-based guidelines to improve athletic training, performance and overall cardiovascular well-being.

Beneficial effects of Apelin-13 on metabolic diseases and exercise

Apelin, a novel endogenous ligand of the G-protein-coupled receptor APJ, is encoded by the APLN gene and can be hydrolyzed into multiple subtypes, with Apelin-13 being one of the most active subtypes of the Apelin family. Recent studies have revealed that Apelin-13 functions as an adipokine that participates in the regulation of different biological processes, such as oxidative stress, inflammation, apoptosis, and energy metabolism, thereby playing an important role in the prevention and treatment of various metabolic diseases. However, the results of recent studies on the association between Apelin-13 and various metabolic states remain controversial. Furthermore, Apelin-13 is regulated or influenced by various forms of exercise and could therefore be categorized as a new type of exercise-sensitive factor that attenuates metabolic diseases. Thus, in this review, our purpose was to focus on the relationship between Apelin-13 and related metabolic diseases and the regulation of response movements, with particular reference to the establishment of a theoretical basis for improving and treating metabolic diseases.