scholarly journals Altered Ca2+ Handling and Oxidative Stress Underlie Mitochondrial Damage and Skeletal Muscle Dysfunction in Aging and Disease

Metabolites ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 424
Author(s):  
Antonio Michelucci ◽  
Chen Liang ◽  
Feliciano Protasi ◽  
Robert T. Dirksen
Keyword(s):  
Skeletal Muscle ◽  
Muscle Dysfunction ◽  
Disuse Atrophy ◽  
Muscle Disorders ◽  
Atp Production ◽  
Skeletal Muscle Dysfunction ◽  
Structural Framework ◽  
Skeletal Muscle Contraction ◽  
Wide Range ◽  
The Impact

Skeletal muscle contraction relies on both high-fidelity calcium (Ca2+) signals and robust capacity for adenosine triphosphate (ATP) generation. Ca2+ release units (CRUs) are highly organized junctions between the terminal cisternae of the sarcoplasmic reticulum (SR) and the transverse tubule (T-tubule). CRUs provide the structural framework for rapid elevations in myoplasmic Ca2+ during excitation–contraction (EC) coupling, the process whereby depolarization of the T-tubule membrane triggers SR Ca2+ release through ryanodine receptor-1 (RyR1) channels. Under conditions of local or global depletion of SR Ca2+ stores, store-operated Ca2+ entry (SOCE) provides an additional source of Ca2+ that originates from the extracellular space. In addition to Ca2+, skeletal muscle also requires ATP to both produce force and to replenish SR Ca2+ stores. Mitochondria are the principal intracellular organelles responsible for ATP production via aerobic respiration. This review provides a broad overview of the literature supporting a role for impaired Ca2+ handling, dysfunctional Ca2+-dependent production of reactive oxygen/nitrogen species (ROS/RNS), and structural/functional alterations in CRUs and mitochondria in the loss of muscle mass, reduction in muscle contractility, and increase in muscle damage in sarcopenia and a wide range of muscle disorders including muscular dystrophy, rhabdomyolysis, central core disease, and disuse atrophy. Understanding the impact of these processes on normal muscle function will provide important insights into potential therapeutic targets designed to prevent or reverse muscle dysfunction during aging and disease.

scholarly journals Sarcopenia in chronic kidney disease – A brief review

2021 ◽  
Vol 35 (2) ◽  
Author(s):  
Beatriz Donato ◽  
◽  
Catarina Teixeira ◽  
Sónia Velho ◽  
Edgar Almeida ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Chronic Kidney Disease ◽  
Kidney Disease ◽  
Muscle Mass ◽  
Physical Performance ◽  
Functional Independence ◽  
Muscle Dysfunction ◽  
Skeletal Muscle Dysfunction ◽  
Age Related ◽  
The Impact

Sarcopenia is a progressive age -related loss of muscle mass associated with a decline in muscle function and physical performance. Patients with chronic kidney disease experience substantial loss of muscle mass, weakness, and poor physical performance. Indeed, with the progression of chronic kidney disease, skeletal muscle dysfunction contributes to mobility limitation, loss of functional independence, and vulnerability to disease complications. There is a lack of robust data on the negative effect of the impact of kidney disease on skeletal muscle dysfunction, as well as on screening and treatment strategies that can be used in clinical practice to prevent functional decline and disability. Therefore, sarcopenia may be an underestimated condition with major implications for people with chronic kidney disease, even before the start of dialysis, which makes research into this topic necessary. The purpose of this review is to expand on some fundamental topics of sarcopenia, with an emphasis on the setting of chronic kidney disease patients.

141 Mild Burns Combined with Diet Induced Demyelination Does Not Affect Skeletal Muscle Function

2021 ◽  
Vol 42 (Supplement_1) ◽  
pp. S94-S94
Author(s):  
Emre Vardarli ◽  
Nisha Bhattarai ◽  
Amina El Ayadi ◽  
Y E Wang ◽  
Jayson W Jay ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Muscle Function ◽  
Diet Group ◽  
Muscle Dysfunction ◽  
Skeletal Muscle Function ◽  
Regular Diet ◽  
Skeletal Muscle Dysfunction ◽  
Significant Difference ◽  
The Impact

Abstract Introduction Severe burns result in decreased skeletal muscle mass and function. Recent evidence suggests that massive burns disrupt the motor-neural system including motor neurons to partially explain skeletal muscle dysfunction in response to burns. However, impact of demyelination on burn induced skeletal muscle dysfunction has not been investigated. The purpose of this study was to determine the impact of exaggerated demyelination on skeletal muscle dysfunction after burn. Methods C57BL/6 (20-25g, male, n = 26) mice were separated into 6 groups (4–5 animals per group) by diet, burn injury and timepoint (burn or sham groups with two different diets measured at two different timepoints). Mice were fed with either cuprizone diet (0.2 %) to induce severe demyelination or regular diet (18 % protein) for 5 weeks prior to injury. Burns were administered by immersing the dorsal side of the animal into ~95 °C hot water for 10 seconds (~15 % body surface area, full thickness burn). In-situ gastrocnemius function was assessed by attaching the distal tendon of the muscle to a lever arm of a force transducer and stimulating the muscle via exposed sciatic nerve while the animal was under anesthesia. In-situ gastrocnemius muscle function was evaluated 3- and 7-days after burn. Results Food intake was 30 % higher in cuprizone diet group compared to the regular diet group (p=0.002). However, there was no significant difference in body weight among groups (p=0.071). No significant difference was found in gastrocnemius wet weight, peak twitch tension, time to reach peak twitch tension, peak twitch half relaxation time, force-frequency relationship, maximum tetanic force, and fatigue index among groups (burn effect, diet effect, time effect, and their interactions; NS). Conclusions Mild burns combined with demyelination by diet had no effect on skeletal muscle function on our timepoints, and 15 % TBSA burn size was not sufficient to induce skeletal muscle dysfunction. The impact of burn induced neural damage on muscle function and performance indicates further investigation.

scholarly journals Pathophysiological mechanisms of alcoholic myopathy - Lessons from rodent models

2021 ◽  
Vol 52 (2) ◽  
Author(s):  
Danielle E. Levitt ◽  
Patricia E. Molina ◽  
Patricia E.Molina Simon
Keyword(s):  
Skeletal Muscle ◽  
At Risk ◽  
Muscle Disease ◽  
Organ Injury ◽  
Muscle Dysfunction ◽  
Rodent Models ◽  
Pathophysiological Mechanisms ◽  
Alcoholic Myopathy ◽  
Skeletal Muscle Dysfunction ◽  
The Impact

Skeletal muscle dysfunction is highly prevalent and is one of the earliest pathological tissue changes among people with at-risk alcohol use. Clinical studies to elucidate pathophysiological mechanisms of alcohol-mediated muscle disease are hampered due to ethical considerations, and confounded by nutritional, lifestyle, and comorbid conditions. Rodent models have been developed to study the impact of at-risk alcohol consumption and alcohol-mediated end organ injury, including skeletal muscle dysfunction. This review discusses results from well-established rodent models of alcohol administration and highlights key pathophysiological mechanisms underlying alcoholic myopathy identified in rodent models. Salient pathways include impaired regenerative capacity, altered anabolic/catabolic balance, impaired mitochondrial bioenergetic function, and skeletal muscle morphological and contractile changes.

scholarly journals Skeletal muscle dysfunction in chronic renal failure: effects of exercise

2006 ◽  
Vol 290 (4) ◽  
pp. F753-F761 ◽  
Author(s):  
Gregory R. Adams ◽  
Nosratola D. Vaziri
Keyword(s):  
Skeletal Muscle ◽  
Renal Failure ◽  
Exercise Capacity ◽  
Muscle Function ◽  
Chronic Illnesses ◽  
Treatment Modalities ◽  
Muscle Dysfunction ◽  
Obstructive Pulmonary Disease ◽  
Skeletal Muscle Dysfunction

A number of chronic illnesses such as renal failure (CRF), obstructive pulmonary disease, and congestive heart failure result in a significant decrease in exercise tolerance. There is an increasing awareness that prescribed exercise, designed to restore some level of physical performance and quality of life, can be beneficial in these conditions. In CRF patients, muscle function can be affected by a number of direct and indirect mechanisms caused by renal disease as well as various treatment modalities. The aims of this review are twofold: first, to briefly discuss the mechanisms by which CRF negatively impacts skeletal muscle and, therefore, exercise capacity, and, second, to discuss the available data on the effects of programmed exercise on muscle function, exercise capacity, and various other parameters in CRF.

scholarly journals Targeted overexpression of mitochondrial catalase protects against cancer chemotherapy-induced skeletal muscle dysfunction

2016 ◽  
Vol 311 (2) ◽  
pp. E293-E301 ◽  
Author(s):  
Laura A. A. Gilliam ◽  
Daniel S. Lark ◽  
Lauren R. Reese ◽  
Maria J. Torres ◽  
Terence E. Ryan ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Cancer Chemotherapy ◽  
Protein Oxidation ◽  
Muscle Function ◽  
Contractile Function ◽  
Muscle Dysfunction ◽  
Skeletal Muscle Dysfunction ◽  
Whole Muscle ◽  
Loss Of Strength ◽  
Mitochondrial Respiratory

The loss of strength in combination with constant fatigue is a burden on cancer patients undergoing chemotherapy. Doxorubicin, a standard chemotherapy drug used in the clinic, causes skeletal muscle dysfunction and increases mitochondrial H2O2. We hypothesized that the combined effect of cancer and chemotherapy in an immunocompetent breast cancer mouse model (E0771) would compromise skeletal muscle mitochondrial respiratory function, leading to an increase in H2O2-emitting potential and impaired muscle function. Here, we demonstrate that cancer chemotherapy decreases mitochondrial respiratory capacity supported with complex I (pyruvate/glutamate/malate) and complex II (succinate) substrates. Mitochondrial H2O2-emitting potential was altered in skeletal muscle, and global protein oxidation was elevated with cancer chemotherapy. Muscle contractile function was impaired following exposure to cancer chemotherapy. Genetically engineering the overexpression of catalase in mitochondria of muscle attenuated mitochondrial H2O2 emission and protein oxidation, preserving mitochondrial and whole muscle function despite cancer chemotherapy. These findings suggest mitochondrial oxidants as a mediator of cancer chemotherapy-induced skeletal muscle dysfunction.

Sign in / Sign up

Export Citation Format

Share Document