Adipose-derived stem cell peptide 5 (ADSCP5) alleviates hypertrophic scarring by modulating PI3K/AKT/mTOR and NF-κB/IL-6 pathways
Background
Hypertrophic scarring (HTS) represents a significant clinical challenge, often leading to functional impairment and cosmetic disfigurement, with current treatments offering limited efficacy. Adipose-derived stem cells (ADSCs) are recognized for their role in inhibiting pathological scar formation, yet the precise molecular mechanisms remain largely undefined. This study investigates ADSCP5, a novel peptide derived from ADSC-conditioned medium, to elucidate its function, mechanism, and therapeutic potential in mitigating HTS by targeting specific intracellular signaling pathways.
Study Design
Researchers investigated ADSCP5 using in vitro hypertrophic scar fibroblast, macrophage-fibroblast coculture, and human umbilical vein endothelial cell (HUVEC) assays. They employed a comprehensive suite of techniques including RNA sequencing, pathway analysis, peptide pull-down, molecular docking, cellular thermal shift assays, surface plasmon resonance, immunofluorescence colocalization analysis, western blotting, rescue experiments, reactive oxygen species (ROS) and autophagy tests, mitochondrial membrane potential assays, and untargeted metabolomics. The therapeutic efficacy of ADSCP5 was further validated in established rabbit and porcine scar models, assessing its ability to attenuate scar formation.
Results
In hypertrophic scar fibroblasts, ADSCP5 significantly downregulated the expression of collagen genes, specifically COL1A1, COL1A2, and COL3A1, along with actin alpha 2, smooth muscle, without affecting cell proliferation, apoptosis, or migration. Transcriptomic, enrichment, and western blot analyses confirmed that ADSCP5 reduced the protein levels of phosphorylated p65 (an NF-κB subunit), p-PI3K, p-AKT, and p-mTOR. Furthermore, ADSCP5 decreased IL-6 transcription. Mechanistically, ADSCP5 directly bound to either pyruvate carboxylase (PC) or the NF-κB subunit p50. This interaction led to the downregulation of PC or the upregulation of p50, which ultimately inhibited collagen expression, a finding corroborated by rescue assays. Additionally, ADSCP5 induced ROS generation and autophagy, altered global metabolism, and modulated macrophage-fibroblast crosstalk to suppress fibrosis. It also exhibited antiangiogenic effects in HUVECs. > In both the rabbit and porcine scar models, ADSCP5 treatment effectively attenuated collagen deposition and scar formation, demonstrating its therapeutic potential in vivo.
Key Findings
- ADSCP5 significantly downregulated
COL1A1,COL1A2, andCOL3A1gene expression in hypertrophic scar fibroblasts. - ADSCP5 reduced protein levels of
p-p65,p-PI3K,p-AKT, andp-mTOR, and decreasedIL-6transcription. - ADSCP5 directly bound to
pyruvate carboxylase (PC)or theNF-κBsubunitp50. - ADSCP5 induced
ROSgeneration and autophagy, modulating macrophage-fibroblast crosstalk to suppress fibrosis. - ADSCP5 treatment effectively attenuated hypertrophic scarring in both rabbit and porcine models.
Why It Matters
This research identifies ADSCP5 as a promising therapeutic agent for hypertrophic scarring, offering a novel peptide-based strategy beyond current limited treatments. The detailed mechanistic insights into its dual targeting of PI3K/AKT/mTOR-autophagy and NF-κB/IL-6 pathways provide a deeper understanding of scar biology and potential intervention points. For clinicians and biohackers, ADSCP5 represents a potential future protocol for scar management, moving beyond symptomatic relief to address underlying fibrotic mechanisms. While preclinical, these findings suggest a path toward developing a usable protocol for reducing collagen overproduction and inflammation in scar tissue, potentially improving both functional and aesthetic outcomes. Further research is needed to translate these findings into human clinical applications and establish optimal dosing and administration.
adscp5
hypertrophic scarring
fibrosis
collagen
pi3k-akt-mtor
nf-kb