Stem Cell Microenvironments and Beyond

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EC

PEC

Wnt

TGF-β

Fibronectin

M-Cadherin

MA

FI

dyMF

dySC

FAP

BL

RL

fat

Laminin-2

Integrin α7β1

TGF-β receptor

Fig. 8.4 The dystrophic niche. The dystrophic fiber (dyMF) is smaller in diameter with centrally
located nuclei, a hallmark of ongoing damage and regeneration. As a result, dySCs are under high
proliferative pressure. Similar to the aged niche, elevated levels of TGF-β and Wnt, as well as
increased numbers of fibroblasts (FIs), are common features of the dystrophic niche. In addition,
inflammation caused by high numbers of fibro/adipogenic progenitors (FAPs) and macrophages
(MAs) contributes to the formation of fat and scar tissue (a denser basal and reticular lamina—BL,
RL) at the expense of muscle tissue. Further abbreviations: EC endothelial cell; PEC periendothe-
lial cell

I. Dinulovic et al.