Myofibrillar but not actomyosin ATPase is depressed in failing myocardium from patients with dilated cardiomyopathy. Since there is a similar depression of myofibrillar ATPase in mitral regurgitation myocardium, we investigated whether or not the hydrolytic and mechanical performances of myosin are altered by comparing the maximal actomyosin ATPase activity and the in vitro myosin motility of myocardial myosin from patients with mitral regurgitation heart failure with that of patients with normal ventricular function. The results show that there is no significant difference (P > .05) between nonfailing and failing values for either the maximal actomyosin ATPase activity (0.3 s-1.head-1) or the myosin motility (1 micron/s). These observations suggest that changes, other than in the myosin heavy chain, contribute to the altered myocardial performance in mitral regurgitation myocardium.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1161/01.res.79.2.222 | DOI Listing |
Scand J Med Sci Sports
January 2025
Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark.
While acute exercise affects sarcoplasmic reticulum (SR) function, the impact of resistance training remains unclear. The purpose of the present study was to investigate SR Ca handling plasticity in response to moderate- and high-volume strength training in elite rowers. Twenty elite male (n = 12) and female (n = 8) rowers performed three weekly strength training sessions for 8 weeks and were randomly allocated to either perform 3 sets (3-SET) or progressive increase from 5 to 10 sets (10-SET) of 10 repetitions during the training period.
View Article and Find Full Text PDFUnlabelled: Myosin-IC (myo1c) is a class-I myosin that supports transport and remodeling of the plasma membrane and membrane-bound vesicles. Like other members of the myosin family, its biochemical kinetics are altered in response to changes in mechanical loads that resist the power stroke. However, myo1c is unique in that the primary force-sensitive kinetic transition is the isomerization that follows ATP binding, not ADP release as in other slow myosins.
View Article and Find Full Text PDFCirc Cardiovasc Qual Outcomes
January 2025
Division of Cardiovascular Medicine, Department of Internal Medicine, Lahey Hospital and Medical Center, Burlington, MA (S.S.D.).
Cells
December 2024
Department of Biological Sciences, Wayne State University, Detroit, MI 48202, USA.
The myosin light chains (MLCs) of non-muscle myosin II are known to regulate cellular architecture and generate cellular forces; they also have an increasingly emerging role in the progression of cancer. The phosphorylation state of the myosin light chains controls the activity of myosins that are implicated in invasion and proliferation. In cancers, when proliferation is greatly increased, cytokinesis relies on phosphorylated light chains to activate the contractile forces used to separate the cells.
View Article and Find Full Text PDFGenes (Basel)
November 2024
Institute of Animal Husbandry and Veterinary Medicine, Ji Lin Academy of Agricultural Sciences, Gongzhuling 136100, China.
: Cultivated meat, an alternative to conventional meat, has substantial potential for alleviating environmental and ethical concerns. This method of manufacturing meat involves the isolation of skeletal muscle satellite cells (SMSCs) from donor animals, after which they proliferate in vitro and differentiate into primitive muscle fibers. The aim of this research was to evaluate how the insulin-like growth factor 1 (IGF1) gene regulates the myogenic differentiation of bovine skeletal muscle satellite cells (bSMSCs).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!