application-consistent-massage-like-perturbations-on-mouse-calves

Application of Consistent Massage-Like Perturbations on Mouse Calves and Monitoring the Resulting Intramuscular Pressure Changes

Massage is generally recognized to be beneficial for relieving pain and inflammation. Although previous studies have reported anti-inflammatory effects of ...

application-passive-head-motion-to-generate-defined-accelerations-at

Application of Passive Head Motion to Generate Defined Accelerations at the Heads of Rodents

Exercise is widely recognized as effective for various diseases and physical disorders, including those related to brain dysfunction. However, molecular ...

National Rehabilitation Center for Persons with disabilities

Physical inactivity gives rise to numerous diseases and organismal dysfunctions, particularly those related to aging. Musculoskeletal disorders including muscle atrophy, which can result from a sedentary lifestyle, aggravate locomotive malfunction and evoke a vicious circle leading to severe functional disruptions of vital organs such as the brain and cardiovascular system. Although the significance of physical activity is evident, molecular mechanisms behind its beneficial effects are poorly understood. Here, we show that massage-like mechanical interventions modulate immobilization-induced pro-inflammatory responses of macrophages  and alleviate muscle atrophy. Local cyclical compression (LCC) on mouse calves, which generates intramuscular pressure waves with amplitude of 50 mmHg, partially restores the myofiber thickness and contracting forces of calf muscles that are decreased by hindlimb immobilization. LCC tempers the increase in the number of cells expressing pro-inflammatory proteins, tumor necrosis factor-α and monocyte chemoattractant protein-1 (MCP-1), including macrophages  The reversing effect of LCC on immobilization-induced thinning of myofibers is almost completely nullified when macrophages recruited from circulating blood are depleted by administration of clodronate liposomes. Furthermore, application of pulsatile fluid shear stress, but not hydrostatic pressure, reduces the expression of MCP-1 in macrophages  Together with the LCC-induced movement of intramuscular interstitial fluid detected by µCT analysis, these results suggest that mechanical modulation of macrophage function is involved in physical inactivity-induced muscle atrophy and inflammation. Our findings uncover the implication of mechanosensory function of macrophages in disuse muscle atrophy, thereby opening a new path to develop a novel therapeutic strategy utilizing mechanical interventions.

Local cyclical compression modulates macrophage function  and alleviates immobilization-induced muscle atrophy.

Performance enhancing substances are becoming increasingly popular amongst bodybuilders and people who want to enhance their physiques. However, due to the rise of the Internet and laws prohibiting sales of these substances without prescription, the route of procurement and administration practices have become more and more dangerous. Prior to the mid-1970's, anabolic steroids were not regulated and easily available from physicians and pharmacies in several countries. In 1990, the United States enacted the Anabolic Steroid Control Act, leading to the proliferation of black markets and underground laboratories. The shift from pharmacy to underground online sites for the procurement of anabolic steroids led to an increase of fake products with low purity and the ability to potentially endanger the health of anabolic steroid users. Underground laboratories emerged both locally and in countries with lax legal regulations. 'Anabolic steroid tourism' and large networks of online resellers emerged, leading to the banalisation of the illegal procurement of anabolic steroids. Furthermore, the increase of anecdotal information spreading on the internet among anabolic steroid user forums nourishes the rampant misinformation and dangerous practices that currently exist. The dosages and ways of administration recommended on these forums can be false and misleading to those who lack a medical background and cannot go to their physician to seek advice because of the fear of repercussions. This review aims to elucidate and describe current practices of the anabolic-androgenic steroids black market and draw attention to potential dangers for users.

Anabolic-androgenic steroids: procurement and administration practices of doping athletes.

In the current aging society, the occurrence of the locomotive syndrome, a condition in which the locomotive organs are impaired, is increasing. The locomotive system includes support (bones), mobility and impact absorption (joints and intervertebral disks), drive and control (muscles, nerves), and network (blood vessels). The impairment of any of those systems can lead to a major decrease in quality of life. In recent years, several studies on methods to improve and prevent conditions impairing the locomotive syndrome have been conducted. Almost in parallel with the structure supporting mobility and body functions, testosterone levels decrease with age. Testosterone is a hormone-regulating several pathways affecting each aspect of the locomotive syndrome. Testosterone is regulated by the pituitary gland triggering several processes in the body through genomic and non-genomic pathways, affecting muscles, bones, nerves, joints, intervertebral discs, and blood vessels. The purpose of this review is to investigate the role of testosterone in each of the systems involved in the locomotive syndrome.

Mobility and Biomechanical Functions in the Aging Male: Testosterone and the Locomotive Syndrome.

Mechanical forces are known to be involved in various biological processes. However, it remains unclear whether brain functions are mechanically regulated under physiological conditions. Here, we demonstrate that treadmill running and passive head motion (PHM), both of which produce mechanical impact on the head, have similar effects on the hallucinogenic 5-hydroxytryptamine (5-HT) receptor subtype 2A (5-HT) signaling in the prefrontal cortex (PFC) of rodents. PHM generates interstitial fluid movement that is estimated to exert shear stress of a few pascals on cells in the PFC. Fluid shear stress of a relevant magnitude on cultured neuronal cells induces ligand-independent internalization of 5-HT receptor, which is observed in mouse PFC neurons after treadmill running or PHM. Furthermore, inhibition of interstitial fluid movement by introducing polyethylene glycol hydrogel eliminates the effect of PHM on 5-HT receptor signaling in the PFC. Our findings indicate that neuronal cell function can be physiologically regulated by mechanical forces in the brain.

Mechanical Regulation Underlies Effects of Exercise on Serotonin-Induced Signaling in the Prefrontal Cortex Neurons.

: Low testosterone and its symptoms is a condition affecting many males with severe repercussions on health. Testosterone affects metabolism, bones, joints, and ligaments, the cardiovascular system, liver, sexual functions, muscle mass, and the nervous system. Nowadays, due to recent research showing the benefits of testosterone replacement therapy, this treatment is gaining in popularity among aging men. However, testosterone replacement can increase the risk of infertility. : Human chorionic gonadotropin (HCG) is used in the treatment of male infertility due to its luteinizing hormone (LH)-like action triggering testosterone and sperm production. Due to these positive effects on testosterone production, HCG has also been used to treat secondary hypogonadism. In this review, based on a literature review for the years 1977-2020 via Google Scholar, we summarize the current research on HCG as treatment for patients suffering from low testosterone and provide an overview of the pros and contras for HCG therapy as compared to testosterone replacement therapy for the treatment of secondary hypogonadism. : The testosterone and sperm production triggering effects of HCG without the side effects on fertility seen in testosterone replacement therapy make HCG therapy a prime candidate for patients suffering from secondary hypogonadism.

ArticleTotal : 2	Year
Publication title Cited by 5	2019
Publication title Cited by 1	2022

Article	Year
Local cyclical compression modulates macrophage function and alleviates immobilization-induced muscle atrophy. Clinical science (London, England : 1979)\| PubMed ID: 30209036	2018
Anabolic-androgenic steroids: procurement and administration practices of doping athletes. The Physician and sportsmedicine\| PubMed ID: 30247933	2019
Mobility and Biomechanical Functions in the Aging Male: Testosterone and the Locomotive Syndrome. The aging male : the official journal of the International Society for the Study of the Aging Male\| PubMed ID: 30269622	2020
Mechanical Regulation Underlies Effects of Exercise on Serotonin-Induced Signaling in the Prefrontal Cortex Neurons. iScience\| PubMed ID: 32062453	2020
Human chorionic gonadotropin treatment: a viable option for management of secondary hypogonadism and male infertility. Expert review of endocrinology & metabolism\| PubMed ID: 33345656	2021

Takahiro Maekawa

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