老化ニッチは,筋肉幹細胞の静止状態を乱します
Joe V Chakkalakal1, Kieran M Jones, M Albert Basson
1Center of Regenerative Medicine, Massachusetts General Hospital, Boston, Massachusetts 02114, USA.
Nature
|October 2, 2012
まとめ
老化している筋肉幹細胞は,ニッチの変化のために機能を失います. 高齢化ニッチにおける線維細胞成長因子 (FGF) 信号伝達の増加は,幹細胞の枯渇を促し,再生を阻害する.
科学分野:
- 幹細胞生物学 幹細胞生物学とは
- 老化に関する研究.
- 筋肉の再生 筋肉の再生
背景:
- 幹細胞の機能は年齢とともに低下し,組織再生に影響を及ぼします.
- 年齢関連の機能低下における幹細胞ニッチの役割は完全に理解されていません.
研究 の 目的:
- 筋肉幹細胞のニッチにおける年齢関連の変化が幹細胞の静止状態と機能にどのように影響するかを調査する.
- ニッチが幹細胞の老化に影響を与える分子メカニズムを特定する.
主な方法:
- 老化における筋肉幹細胞の行動を研究するためにマウスモデルを使用した.
- 操作された線維芽細胞成長因子 (FGF) は,衛星細胞とそのニッチの信号伝達経路です.
- 衛星細胞の静止,枯渇,再生能力を評価した.
主要な成果:
- 老化した筋肉幹細胞のニッチ (筋肉繊維) はFGF2を発現させ,衛星細胞の活性化と自己再生の喪失を促進します.
- 歳をとった衛星細胞は,FGFシグナル伝達阻害体であるsprouty1 (Spry1) を発現する.
- Spry1を阻害したり,FGFのシグナリングを増加させたりすると,衛星細胞の枯渇と再生の減少につながった.
- FGFR1を抑制したり,Spry1を過剰に発現させたりすることで,FGFシグナル伝達を減少させ,保存された衛星細胞数を保存します.
結論:
- 筋肉幹細胞のニッチにおける年齢依存の変化を特定した.
- ニッチ派生FGFシグナリングが,高齢化中の幹細胞の静止状態と機能に直接影響することを実証した.
- FGFシグナリングを調節し,老化組織における幹細胞機能を維持する可能性を強調した.
関連する概念動画
Adult Stem Cells
27.8K
Stem cells are undifferentiated cells that divide and produce more stem cells or progenitor cells that differentiate into mature, specialized cell types. All the cells in the body are generated from stem cells in the early embryo, but small populations of stem cells are also present in many adult tissues including the bone marrow, brain, skin, and gut. These adult stem cells typically produce the various cell types found in that tissue—to replace cells that are damaged or to continuously...
27.8K
Multipotency of Hematopoietic Stem Cells
3.1K
The hematopoietic stem cells or HSCs are multipotent, meaning they can differentiate and give rise to all blood and immune cells. HSCs are maintained in the quiescent stage until an external stimulus initiates their differentiation. The multipotent HSCs exist as two heterogeneous populations, long-term repopulating cells (LTRC) and short-term repopulating cells (STRC). The two HSC populations have different surface markers or receptors and are classified based on quiescence and long-term...
3.1K
Satellite Stem Cells and Muscular Dystrophy
1.7K
Satellite stem cells or myosatellite cells are quiescent stem cells that Alexander Mauro first identified in 1961. These cells are located between the sarcolemma, the plasma membrane of muscle fibers, and the basal lamina, the connective tissue sheath covering it. These mononucleated cells are activated in response to muscle injury, can transform into myoblasts, and may form or repair muscle fibers. Myosatellite cells can provide additional myonuclei for muscle regeneration or return to a...
1.7K
Stem Cell Niche
5.0K
The stem cell niche is the dynamic microenvironment where stem cells reside. Inside these niches, the cells may remain undifferentiated, undergo high self-renewal, or become lineage-specific progenitors. Stem cells coexist with other niche cells, such as stromal cells. They also interact closely with the ECM. Cell-cell and cell-matrix communication occur via adhesion molecules or soluble factors that signal the stem cells and determine their fate. Stromal cells also provide survival signals to...
5.0K
Multipotency and Niche of Bulge Stem Cell
2.9K
A hair follicle or HF is a small part of the skin that produces the hair shaft. Paul Gerson Unna was the first to observe a bulge in the human hair follicle's outer root sheath (ORS). The bulge is present between the sebaceous gland and the arrector pili muscle and is the niche for hair follicle stem cells (HFSCs). The bulge is also a niche for melanocyte stem cells, and their loss results in graying of hair. The HFSCs express Sox9 and Lhx2, which help them maintain stemness and prevent...
2.9K
The Effect of Aging on Tissues
3.6K
Several body functions deteriorate with age. The external signs of aging are easily identifiable. For example, the skin becomes dry, less elastic, and thins out, forming wrinkles. The skin of the face begins to appear looser due to a decrease in the levels of elastic and collagen fibers in the connective tissue. Additionally, melanin production in the hair follicle decreases with age, resulting in gray hair. Moreover, the senses of sight and hearing decline, so glasses and hearing aids may...
3.6K


