skeletal muscle tissue regeneration

Definition

Target type: biologicalprocess

The regrowth of skeletal muscle tissue to repair injured or damaged muscle fibers in the postnatal stage. [GOC:ef, GOC:mtg_muscle, PMID:12021255, PMID:16607119]

Skeletal muscle regeneration is a complex and tightly regulated process that involves a coordinated interplay of various cellular and molecular events. It is initiated by muscle injury, which can occur due to trauma, overuse, or disease. The process can be broadly divided into three phases:

1. **Inflammation and Debris Removal:** Following injury, the damaged muscle fibers undergo necrosis, releasing inflammatory mediators and cellular debris. These signals attract immune cells, such as neutrophils and macrophages, to the injury site. Neutrophils primarily clear cellular debris, while macrophages phagocytose dead cells and release growth factors that promote tissue repair.

2. **Satellite Cell Activation and Proliferation:** Satellite cells, quiescent stem cells located beneath the basal lamina of muscle fibers, are activated in response to injury. They proliferate and differentiate into myoblasts, which are committed progenitor cells capable of fusing together to form new muscle fibers.

3. **Myoblast Differentiation and Fusion:** Myoblasts migrate to the injury site and fuse with each other or with existing muscle fibers, forming multinucleated myotubes. These myotubes undergo maturation and further differentiation, acquiring the characteristics of mature muscle fibers, such as contractile proteins and specialized organelles.

**Key Molecular Players:**

* **Growth Factors:** Multiple growth factors, including fibroblast growth factor (FGF), hepatocyte growth factor (HGF), insulin-like growth factor (IGF), and transforming growth factor (TGF)-beta, play crucial roles in regulating satellite cell activation, proliferation, and differentiation.
* **Cytokines:** Inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 (IL-1), are involved in the initial inflammatory response and recruit immune cells.
* **Extracellular Matrix Molecules:** Collagen, laminin, and fibronectin, components of the extracellular matrix, provide structural support and influence cell adhesion, migration, and differentiation.
* **Transcription Factors:** Transcription factors, such as MyoD, Myf5, and MRF4, regulate the expression of muscle-specific genes during myoblast differentiation.

**Factors Influencing Regeneration:**

* **Age:** Muscle regeneration capacity declines with age, resulting in slower and less efficient repair.
* **Severity of Injury:** The extent of muscle damage influences the regenerative response.
* **Underlying Conditions:** Conditions such as diabetes, obesity, and chronic inflammation can impair muscle regeneration.
* **Exercise and Nutrition:** Regular exercise and a balanced diet can enhance muscle regeneration.

Skeletal muscle regeneration is an essential process for maintaining muscle function and restoring tissue integrity after injury. Understanding the complex molecular mechanisms involved in this process is crucial for developing strategies to promote muscle repair and treat muscle-related diseases.'
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Proteins (3)

Compounds (8)