Article
Biochemistry & Molecular Biology
Bo Song, Yating Cheng, Md. Abul Kalam Azad, Sujuan Ding, Kang Yao, Xiangfeng Kong
Summary: This study investigated the molecular basis for differences in meat yield and quality between Duroc, Taoyuan black (TB), and Xiangcun black (XB) pigs. The results show that TB pigs have higher fat percentage, intramuscular fat content, and antioxidant capacity, but lower carcass weight, lean percentage, pH decline, and glycolytic potential compared to Duroc pigs. Moreover, TB pigs have lower expression of protein synthesis and lipolysis genes in their muscles. Targeted metabolome analysis revealed significant differences in 24 metabolites among the three pig breeds. Correlation analysis suggests that l-malic acid and β-alanine contents in muscles are closely related to meat quality. These findings suggest that the excellent meat quality of TB pigs is attributed to muscle metabolism and fiber characteristics, while lower protein synthesis and lipolysis contribute to less meat yield.
Article
Biochemistry & Molecular Biology
Shoji Tanaka, Naotoshi Sugimoto, Takako Ohno-Shosaku, Sachiko Madokoro, Pleiades Tiharu Inaoka, Toshiaki Yamazaki
Summary: This study examined the effects of theobromine on skeletal muscles in rats. The results showed that long-term consumption of a 0.05% theobromine diet had no significant effect on muscle hypertrophy and contractile properties. However, theobromine had similar effects to clenbuterol in upregulating the expression of myosin heavy chain 2x and myogenic differentiation 1.
MOLECULAR BIOLOGY REPORTS
(2022)
Review
Cell Biology
Shoko Sawano, Wataru Mizunoya
Summary: This review summarizes the history of muscle fiber type classification and various staining methods used. The development of experimental methods for detecting myosin heavy chain proteins and the improvement in immunostaining with monoclonal antibodies are discussed. The information presented in this review will guide researchers in selecting optimal staining methods for their experimental conditions and purposes.
HISTOLOGY AND HISTOPATHOLOGY
(2022)
Article
Cell Biology
Michaeljohn Kalakoutis, Ross D. D. Pollock, Norman R. R. Lazarus, R. Andrew Atkinson, Marc George, Onur Berber, Roger C. C. Woledge, Julien Ochala, Stephen D. R. Harridge
Summary: The specific force (SF) of human aging in single muscle fibers is inconsistent in different studies, which may result from variations in the health status/physical activity levels and methodological differences. This study compared SF in fibers from older hip fracture patients, healthy master cyclists, and healthy nontrained young adults using two different activating solutions. The results showed that the activating solution significantly affected the force and revealed a difference in sensitivity in muscle fibers of hip fracture patients.
AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY
(2023)
Article
Geriatrics & Gerontology
David Martin, Kevin Nay, Francois Robin, Amelie Rebillard, Luz Orfila, Brice Martin, Patricia Leroyer, Pascal Guggenbuhl, Suzanne Dufresne, Philippe Noirez, Martine Ropert, Olivier Loreal, Frederic Derbre
Summary: This study investigates the impact of iron excess on skeletal muscle structure and metabolic adaptations. The results suggest that skeletal muscle can protect itself from the deleterious effects of iron overload under pathophysiological conditions.
JOURNAL OF CACHEXIA SARCOPENIA AND MUSCLE
(2022)
Article
Orthopedics
Lisanne Aranha, Charu Eapen, Vivek D. Patel, Ashish J. Prabhakar, Karthik Hariharan
Summary: Alterations in body postures and elevation angles affect the fatigue response of rotator cuff muscles, with supraspinatus muscle showing significant fatigue during standing with 90-degree elevation.
ARCHIVES OF ORTHOPAEDIC AND TRAUMA SURGERY
(2023)
Article
Physiology
Kyle B. Spainhower, Allan K. Metz, Abdel-Ruhman S. Yusuf, Lydia E. Johnson, Judy A. Avey-Arroyo, Michael T. Butcher
Summary: The research found differences in slow myosin heavy chain fiber type distribution and energy metabolism in the hindlimbs of three-toed and two-toed sloths, indicating potential adaptations for force production and energy savings in sloth hindlimb muscles. Furthermore, differences in enzyme activity levels between anaerobic and aerobic enzymes suggest potential functional adaptations in sloth limbs beyond muscle fiber type expression.
JOURNAL OF COMPARATIVE PHYSIOLOGY B-BIOCHEMICAL SYSTEMS AND ENVIRONMENTAL PHYSIOLOGY
(2021)
Review
Biochemistry & Molecular Biology
Gabryela Kuhnen, Tiago Guedes Russomanno, Marta Murgia, Nicolas J. Pillon, Martin Schoenfelder, Henning Wackerhage
Summary: Adult skeletal muscle fibres can be classified into different types based on the expression of specific genes. The proportions of these muscle fibre types can be altered through gene gain or loss-of-function. In particular, transcriptional regulators play a significant role in regulating the expression of muscle fibre-specific genes. After exercise, the expression of certain genes increases or decreases, suggesting their involvement in muscle fibre adaptation. DNA sequence variants of muscle fibre genes may contribute to the variation in muscle fibre type proportions in the human population.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Biophysics
Takuma Yuri, Jose H. Trevino, Alexander Hooke, Hugo Giambini
Summary: This study investigated the moment arms of different subregions of four muscles during shoulder flexion, revealing that they have varying roles in stabilizing and flexing the shoulder. The posterior deep subregion of the supraspinatus muscle acts as a flexor in early range and as a stabilizer in mid-to-end range of flexion.
JOURNAL OF BIOMECHANICS
(2022)
Review
Biology
Daniela D'Amico, Roberto Fiore, Daniela Caporossi, Valentina Di Felice, Francesco Cappello, Ivan Dimauro, Rosario Barone
Summary: Skeletal muscle is a plastic tissue rich in proteins, and physical exercise serves as a physiological stressor that stimulates the increase of heat shock proteins, such as Hsp60 and alpha B-crystallin, which play important roles in muscle physiopathology. The modulation of these proteins is essential for facilitating cellular remodeling processes related to training adaptations, and understanding their specific distribution within skeletal muscle fiber-types could lead to better personalized training protocols.
Article
Orthopedics
Michael B. B. Kuenzler, Michelle H. H. McGarry, Masaki Akeda, Hansel Ihn, Agnieszka Karol, Brigitte von Rechenberg, Michael O. O. Schaer, Matthias A. A. Zumstein, Thay Q. Q. Lee
Summary: This study aimed to examine the feasibility of oral PARP-1 inhibition and investigate its influence on rat supraspinatus enthesis and muscle healing after rotator cuff repair. The results showed that oral veliparib was safe for the rats and improved enthesis healing and muscle fiber size. Therefore, it can be considered as a potential treatment to promote healing after rotator cuff tear.
AMERICAN JOURNAL OF SPORTS MEDICINE
(2023)
Article
Physiology
Laura S. S. Vasquez-Bolanos, Michael C. C. Gibbons, Severin Ruoss, Isabella T. T. Wu, Mario Vargas-Vila, Sydnee A. A. Hyman, Mary C. C. Esparza, Donald C. C. Fithian, John G. G. Lane, Anshuman Singh, Chanond A. A. Nasamran, Kathleen M. M. Fisch, Samuel R. R. Ward
Summary: This study analyzed transcriptional changes in rabbit supraspinatus muscle tissue at different time points post-tenotomy, revealing unique patterns of gene expression with the greatest changes observed at 1 week and a resurgence at 16 weeks. The findings provide insights into the biological mechanisms of chronic muscle degeneration after rotator cuff tears.
FRONTIERS IN PHYSIOLOGY
(2021)
Article
Anatomy & Morphology
Colin W. Moore, Jacob Fanous, Charles L. Rice
Summary: The study compared the proportion of type I and type II muscle fibers in the APB based on its relationship with the PL tendon, indicating that APB fascicles arranged in a digastric relationship with the PL may have the capacity to produce more powerful contractions than those with rudimentary PL tendons.
JOURNAL OF ANATOMY
(2021)
Article
Anatomy & Morphology
Anton Ronnblom, Lars-Eric Thornell, Farhan Shah, Krister Tano, Per Stal
Summary: The function of the middle ear muscles in hearing and protection is still unclear. This study analyzed the morphology, fiber composition, and metabolic properties of these muscles, and found that they have a high proportion of fast contracting myosin fibers and unique muscle characteristics. The middle ear muscles differ from other muscles in terms of fiber size, capillarization, oxidative activity, and nerve density.
JOURNAL OF ANATOMY
(2023)
Article
Orthopedics
Jun Umehara, Masahide Yagi, Yasuyuki Ueda, Shusuke Nojiri, Kotono Kobayashi, Takashi Tachibana, Katsuya Nobuhara, Noriaki Ichihashi
Summary: Rotator cuff tear is a common shoulder injury that causes shoulder dysfunction and pain. Surgical repair is the primary treatment, but impaired force exertion and compensatory changes in synergist muscles persist even after repair. This study aimed to identify the compensation strategy of shoulder abductors in patients with rotator cuff repair. The results showed individual variations in the compensatory increase of specific muscles, suggesting a non-stereotypical compensation strategy in these patients.
JOURNAL OF ORTHOPAEDIC RESEARCH
(2023)
