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Cellular Signalling Dec 2018Vascular smooth muscle cells (VSMCs) are the major cell type in blood vessels. Unlike many other mature cell types in the adult body, VSMC do not terminally... (Review)
Review
Vascular smooth muscle cells (VSMCs) are the major cell type in blood vessels. Unlike many other mature cell types in the adult body, VSMC do not terminally differentiate but retain a remarkable plasticity. Fully differentiated medial VSMCs of mature vessels maintain quiescence and express a range of genes and proteins important for contraction/dilation, which allows them to control systemic and local pressure through the regulation of vascular tone. In response to vascular injury or alterations in local environmental cues, differentiated/contractile VSMCs are capable of switching to a dedifferentiated phenotype characterized by increased proliferation, migration and extracellular matrix synthesis in concert with decreased expression of contractile markers. Imbalanced VSMC plasticity results in maladaptive phenotype alterations that ultimately lead to progression of a variety of VSMC-driven vascular diseases. The nature, extent and consequences of dysregulated VSMC phenotype alterations are diverse, reflecting the numerous environmental cues (e.g. biochemical factors, extracellular matrix components, physical) that prompt VSMC phenotype switching. In spite of decades of efforts to understand cues and processes that normally control VSMC differentiation and their disruption in VSMC-driven disease states, the crucial molecular mechanisms and signalling pathways that shape the VSMC phenotype programme have still not yet been precisely elucidated. In this article we introduce the physiological functions of vascular smooth muscle/VSMCs, outline VSMC-driven cardiovascular diseases and the concept of VSMC phenotype switching, and review molecular mechanisms that play crucial roles in the regulation of VSMC phenotypic plasticity.
Topics: Animals; Cell Differentiation; Cell Plasticity; Cell Proliferation; Cells, Cultured; Epigenesis, Genetic; Extracellular Matrix; Humans; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Phenotype; Signal Transduction; Vascular Diseases
PubMed: 30172025
DOI: 10.1016/j.cellsig.2018.08.019 -
The FEBS Journal Nov 2022Regeneration of the mammalian adult skeletal muscle is a well-orchestrated process regulated by multiple proteins and signalling pathways. Cytokines constitute a major... (Review)
Review
Regeneration of the mammalian adult skeletal muscle is a well-orchestrated process regulated by multiple proteins and signalling pathways. Cytokines constitute a major class of regulators of skeletal myogenesis. It is well established that infiltrating immune cells at the site of muscle injury secrete cytokines, which play critical roles in the myofibre repair and regeneration process. In the past 10-15 years, skeletal muscle itself has emerged as a prolific producer of cytokines. Much attention in the field has been focused on the endocrine effects of muscle-secreted cytokines (myokines) on metabolic regulation. However, ample evidence suggests that muscle-derived cytokines also regulate myogenic differentiation and muscle regeneration in an autocrine manner. In this review, we survey cytokines that meet two criteria: (a) evidence of expression by muscle cells; (b) evidence demonstrating a myogenic function. Dozens of cytokines representing several major classes make up this group, and together they regulate all steps of the myogenic process. How such a large array of cytokines coordinate their signalling to form a regulatory network is a fascinating, pressing question. Functional studies that can distinguish the source of the cytokines in vivo are also much needed in order to facilitate exploration of their full therapeutic potential.
Topics: Animals; Cell Differentiation; Cytokines; Mammals; Muscle Cells; Muscle Development; Muscle, Skeletal; Regeneration
PubMed: 35073461
DOI: 10.1111/febs.16372 -
Handbook of Experimental Pharmacology 2022In humans, smooth muscle cells (SMCs) are the main cell type in the artery medial layer, in pre-atherosclerotic diffuse thickening of the intima, and in all stages of... (Review)
Review
In humans, smooth muscle cells (SMCs) are the main cell type in the artery medial layer, in pre-atherosclerotic diffuse thickening of the intima, and in all stages of atherosclerotic lesion development. SMCs secrete the proteoglycans responsible for the initial binding and retention of atherogenic lipoproteins in the artery intima, with this retention driving foam cell formation and subsequent stages of atherosclerosis. In this chapter we review current knowledge of the extracellular matrix generated by SMCs in medial and intimal arterial layers, their relationship to atherosclerotic lesion development and stabilization, how these findings correlate with mouse models of atherosclerosis, and potential therapies aimed at targeting the SMC matrix-lipoprotein interaction for atherosclerosis prevention.
Topics: Animals; Atherosclerosis; Lipoproteins; Mice; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Proteoglycans
PubMed: 33340050
DOI: 10.1007/164_2020_364 -
Current Opinion in Pharmacology Jun 2017Under basal conditions, postnatal skeletal muscle displays little cell turnover. With injury, muscle initiates a rapid repair response to reseal damaged membrane,... (Review)
Review
Under basal conditions, postnatal skeletal muscle displays little cell turnover. With injury, muscle initiates a rapid repair response to reseal damaged membrane, reactivating many developmental pathways to facilitate muscle regeneration and prevent tissue loss. Muscle precursor cells become activated accompanied by differentiation and fusion during both muscle growth and regeneration; inter-cellular communication is required for successful completion of these processes. Cellular communication is mediated by lipids, fusogenic membrane proteins, and exosomes. Muscle-derived exosomes carry proteins and micro RNAs as cargo. Secreted factors such as IGF-1, TGFβ, and myostatin are also released by muscle cells providing local signaling cues to modulate muscle fusion and regeneration. Proteins that regulate myoblast fusion also participate in membrane repair and regeneration. Here we will review methods of muscle cell communication focusing on proteins that mediate membrane fusion, exosomes, and autocrine factors.
Topics: Animals; Cell Communication; Cell Membrane; Exosomes; Humans; MicroRNAs; Muscle Cells; Muscle, Skeletal; Phospholipids; Regeneration
PubMed: 28419894
DOI: 10.1016/j.coph.2017.03.008 -
Physiological Reviews Oct 2021The design of the energy metabolism system in striated muscle remains a major area of investigation. Here, we review our current understanding and emerging hypotheses... (Review)
Review
The design of the energy metabolism system in striated muscle remains a major area of investigation. Here, we review our current understanding and emerging hypotheses regarding the metabolic support of muscle contraction. Maintenance of ATP free energy, so called energy homeostasis, via mitochondrial oxidative phosphorylation is critical to sustained contractile activity, and this major design criterion is the focus of this review. Cell volume invested in mitochondria reduces the space available for generating contractile force, and this spatial balance between mitochondria acontractile elements to meet the varying sustained power demands across muscle types is another important design criterion. This is accomplished with remarkably similar mass-specific mitochondrial protein composition across muscle types, implying that it is the organization of mitochondria within the muscle cell that is critical to supporting sustained muscle function. Beyond the production of ATP, ubiquitous distribution of ATPases throughout the muscle requires rapid distribution of potential energy across these large cells. Distribution of potential energy has long been thought to occur primarily through facilitated metabolite diffusion, but recent analysis has questioned the importance of this process under normal physiological conditions. Recent structural and functional studies have supported the hypothesis that the mitochondrial reticulum provides a rapid energy distribution system via the conduction of the mitochondrial membrane potential to maintain metabolic homeostasis during contractile activity. We extensively review this aspect of the energy metabolism design contrasting it with metabolite diffusion models and how mitochondrial structure can play a role in the delivery of energy in the striated muscle.
Topics: Animals; Energy Metabolism; Humans; Mitochondria, Muscle; Muscle Cells; Muscle, Striated
PubMed: 33733879
DOI: 10.1152/physrev.00040.2020 -
Critical Reviews in Biomedical... 2022This paper presents a review of studies on the effects of local vibration training (LVT) on muscle strength along with the associated changes in neuromuscular and cell... (Review)
Review
This paper presents a review of studies on the effects of local vibration training (LVT) on muscle strength along with the associated changes in neuromuscular and cell dynamic responses. Application of local/direct vibration can significantly change the structural properties of muscle cell and can improve muscle strength. The improvement is largely dependent on vibration parameters such as amplitude and frequency. The results of 20 clinical studies reveal that electromyography (EMG) and maximal voluntary contraction (MVC) vary depending on vibration frequency, and studies using frequencies of 28-30 Hz reported greater increases in muscle activity in terms of EMG (rms) value and MVC data than the studies using higher frequencies. A greater muscle activity can be related to the recruitment of large motor units due to the application of local vibration. A greater increase in EMG (rms) values for biceps and triceps during extension than flexion under LVT suggests that types of muscles and their functions play an important role. Although a number of clinical trials and animal studies have demonstrated positive effects of vibration on muscle, an optimum training protocol has not been established. An attempt is made in this study to investigate the optimal LVT conditions on different muscles through review and analysis of published results in the literature pertaining to the changes in the neuromuscular activity. Directions for future research are discussed with regard to identifying optimal conditions for LVT and better understanding of the mechanisms associated with effects of vibration on muscles.
Topics: Electromyography; Muscle Cells; Muscle Contraction; Muscle Strength; Muscle, Skeletal; Vibration
PubMed: 35997107
DOI: 10.1615/CritRevBiomedEng.2022041625 -
Food Research International (Ottawa,... Jun 2023Scaffolds suitable for use in food products are essential in cultured meat production. Simultaneously, efforts are being undertaken to strengthen the scaffolding to... (Review)
Review
Scaffolds suitable for use in food products are essential in cultured meat production. Simultaneously, efforts are being undertaken to strengthen the scaffolding to improve cell proliferation, differentiation, and tissue formation. Muscle cells proliferate and differentiate according to the directional patterns of the scaffold, similar to natural tissue and native muscle tissue. Therefore, establishing an aligned pattern in the scaffolding architecture is vital for cultured meat applications. Recent studies on the fabrication of scaffolds with aligned porosity structures and their utility in manufacturing cultured meat are highlighted in this review. In addition, the directional growth of muscle cells in terms of proliferation and differentiation has also been explored, along with the aligned scaffolding architectures. The aligned porosity architecture of the scaffolds supports the texture and quality of meat-like structures. Although it is difficult to build adequate scaffolds for culturing meat manufactured from diverse biopolymers, it is necessary to develop novel methods to create aligned scaffolding structures. Furthermore, to avoid animal slaughter in the future, it will be imperative to adopt non-animal-based biomaterials, growth factors, and serum-free media conditions for quality meat production.
Topics: Biocompatible Materials; Tissue Scaffolds; Porosity; Tissue Engineering; Muscles; Muscle Cells; Cell Proliferation
PubMed: 37120206
DOI: 10.1016/j.foodres.2023.112755 -
Ageing Research Reviews Jan 2011Skeletal muscle regeneration is a coordinate process in which several factors are sequentially activated to maintain and preserve muscle structure and function. The... (Review)
Review
Skeletal muscle regeneration is a coordinate process in which several factors are sequentially activated to maintain and preserve muscle structure and function. The major role in the growth, remodeling and regeneration is played by satellite cells, a quiescent population of myogenic cells that reside between the basal lamina and plasmalemma and are rapidly activated in response to appropriate stimuli. However, in several muscle conditions, including aging, the capacity of skeletal muscle to sustain an efficient regenerative pathway is severely compromised. Nevertheless, if skeletal muscle possesses a stem cell compartment it is not clear why the muscle fails to regenerate under pathological conditions. Either the resident muscle stem cells are too rare or intrinsically incapable of repairing major damage, or perhaps the injured/pathological muscle is a prohibitive environment for stem cell activation and function. Although we lack definitive answers, recent experimental evidences suggest that the mere presence of endogenous stem cells may not be sufficient to guarantee muscle regeneration, and that the presence of appropriate stimuli and factors are necessary to provide a permissive environment that permits stem cell mediated muscle regeneration and repair. In this review we discuss the molecular basis of muscle regeneration and how aging impacts stem cell mediated muscle regeneration and repair.
Topics: Aging; Animals; Humans; Inflammation; Muscle Cells; Muscle, Skeletal; Muscles; Regeneration; Satellite Cells, Skeletal Muscle
PubMed: 19683075
DOI: 10.1016/j.arr.2009.08.001 -
Wiley Interdisciplinary Reviews.... 2009Muscle stem cells comprise different populations of stem and progenitor cells found in embryonic and adult tissues. A number of signaling and transcriptional networks... (Review)
Review
Muscle stem cells comprise different populations of stem and progenitor cells found in embryonic and adult tissues. A number of signaling and transcriptional networks are responsible for specification and survival of these cell populations and regulation of their behavior during growth and regeneration. Muscle progenitor cells are mostly derived from the somites of developing embryos, while satellite cells are the progenitor cells responsible for the majority of postnatal growth and adult muscle regeneration. In resting muscle, these stem cells are quiescent, but reenter the cell cycle during their activation, whereby they undergo decisions to self-renew, proliferate, or differentiate and fuse into multinucleated myofibers to repair damaged muscle. Regulation of muscle stem cell activity is under the precise control of a number of extrinsic signaling pathways and active transcriptional networks that dictate their behavior, fate, and regenerative potential. Here, we review the networks responsible for these different aspects of muscle stem cell biology and discuss prevalent parallels between mechanisms regulating the activity of embryonic muscle progenitor cells and adult satellite cells.
Topics: Animals; Gene Expression Regulation; Gene Regulatory Networks; Humans; Mice; Muscle Cells; Signal Transduction; Stem Cells
PubMed: 20835986
DOI: 10.1002/wsbm.11 -
Biomedical Microdevices Dec 2012Actuation is an essential function of any artificial or living machine, allowing its movement and its interaction with the surrounding environment. Living muscles have... (Review)
Review
Actuation is an essential function of any artificial or living machine, allowing its movement and its interaction with the surrounding environment. Living muscles have evolved over millions of years within animals as nature's premier living generators of force, work and power, showing unique characteristics in comparison with standard artificial actuators. Current actuation technologies actually represent a real bottleneck in many robotics and ICT applications, including the bio-inspired ones. Main limitations involve inertia and backdrivability, stiffness control and power consumption. The development of novel actuators able to better mimic or even to overcome living muscle performances would open new horizons in robotics and ICT technologies: these components would allow the raise of a new generation of machines, with life-like movements and outstanding performances. An innovative solution to achieve this goal is represented by the merging between artificial and living entities, towards the realization of bio-hybrid devices. The aim of the present article is to describe the scientific and technological efforts made by researchers in the last two decades to achieve cell- or tissue-based actuators, with the dream of matching or outperforming natural muscles and to efficiently power micro- and mini-devices. The main challenges connected to the development of a cell-based actuator are highlighted and the most recent solutions to this scientific/technological problem are depicted, reporting advantages and drawbacks of each single approach. Future perspectives are also described, envisioning bio-hybrid actuators as key components of a new generation of machines able to show life-like movements and behaviors.
Topics: Animals; Computer Simulation; Equipment Design; Models, Biological; Muscle Cells; Muscle Contraction; Muscle, Skeletal; Robotics; Tissue Engineering
PubMed: 22960907
DOI: 10.1007/s10544-012-9697-9