CCN2 induces cellular senescence in fibroblasts

Area of Science:

• Cell Biology
• Fibrosis Research
• Wound Healing

Background:

• Connective tissue growth factor (CCN2) is implicated in fibrosis, but its role in fibroblast behavior and fibrogenesis remains debated.
• Understanding CCN2's precise mechanisms is crucial for developing anti-fibrotic therapies.

Purpose of the Study:

• To investigate the role of CCN2 in inducing fibroblast senescence and its subsequent effects on fibrogenesis.
• To elucidate the molecular pathways through which CCN2 influences fibroblast senescence and extracellular matrix production.

Main Methods:

• In vitro and in vivo studies using fibroblasts.
• Analysis of senescence markers, reactive oxygen species, and key signaling proteins (p53, p16INK4a).
• Cutaneous wound healing models with CCN2 knockdown and protein application.

Main Results:

• CCN2 induces fibroblast senescence via integrin α6β1, leading to reactive oxygen species accumulation, p53 activation, and p16INK4a induction.
• Senescent cells exhibit an anti-fibrotic senescence-associated secretory phenotype (SASP) with reduced collagen and increased matrix metalloproteinases.
• CCN2 application accelerates wound healing by promoting senescence and reducing collagen deposition, while its knockdown has minimal impact.

Conclusions:

• CCN2 acts as an inducer of fibroblast senescence, promoting an anti-fibrotic SASP.
• CCN2 exhibits context-dependent anti-fibrotic effects, particularly evident in wound healing models.
• Targeting CCN2-induced senescence presents a potential therapeutic strategy for fibrotic diseases.