Tendon stem/progenitor cell ageing: Modulation and rejuvenation

Table 1 Recent main factors for regulating tendon stem/progenitor cells biological features

Factor	Cell source	Interventional details	Results	Ref.
PRP	SD rats	10% PRP	10% PRP augments and accelerates the effects of TSPCs on the healing process	[37]
BMACs and PRP complex	Human	A T75 flask (450 μL of BMACs and PRP)	BMAC–PRP enhances the proliferation and migration of TSPCs	[38]
PRP	SD rats	2% PRGF	PRP can activate TSPCs to improve the quality of Achilles tendon rupture healing	[39]
IGF-1, GDF-5 and TGFβ1	Lewis rats	Each growth factor (1, 10, and 100 ng/mL)	GDF-5 promotes TSPCs tenogenic differentiation, and TGFβ1 and IGF-1 increase TSPCs proliferation and are beneficial for phenotype maintenance	[40]
IL-1β	Dogs	-	The expression of inflammatory cytokines is dramatically up-regulated in injured tendon	[41,42]
IL-1β	Mouse	IL-1β (1, 5 or 10 ng/mL)	IL-1β strongly and irreversibly impairs tenogenic and osteogenic differentiation potentials of TSPCs	[43]
IL-6	SD rats	IL-6 (0, 0.1, 1, 10, and 100 ng/mL)	IL-6 enhances proliferation and inhibites tenogenic differentiation in TSPCs via the JAK/Stat3 pathway	[44]
IL-10	SD rats	IL‑10 (0, 0.1, 1, 10 or 100 ng/mL)	IL‑10 enhances cell proliferation and migration, and inhibites tenogenic differentiation in TSPCs	[7]
CTGF	SD rats	CTGF (100 ng/mL)	CTGF plays a role in anti-inflammatory, leading to enhanced tendon healing	[45]
Annexin A1	WT and DF508 mice	-	Decreased annexin A1 expression resulted in elevation of inflammation during the mouse tendon injury process	[46]
Celastrol	Human	celastrol (0, 1, 2, and 4 μM)	Celastrol exerts beneficial effects on human TSPCs stemness and the vital role of the HIF1α-Smad7 pathway in the process is elucidated	[47]
Celecoxib	C57 mouse	celecox (0.1, 1, 10 and 100 ug/mL)	Celecoxib inhibits tenogenic differentiation of TSPCs but has no effects on cell proliferation	[48]
Aspirin	SD rats	Aspirin (1, 2, and 5 mM)	A high concentration of aspirin induces apoptosis in TPSCs by delaying the activation of Wnt/β-catenin pathway	[49]

PRP: Platelet-rich plasma; SD: Sprague–Dawley; TSPCs: Tendon stem/progenitor cells; BMACs: Bone marrow aspirate concentrates; PRGF: Platelet-rich growth factors; CTGF: Connective tissue growth factor; IL-10: Interleukin-10; IL-1β: Interleukin‑1β; TGFβ1: Transforming growth factor-β1; GDF-5: Growth and differentiation factor-5; IGF-1: Insulin-like growth factor1.