Comparative Analysis of Collagen Induction in Sprague Dawley Rat Model Using Absorbable Threads for Facial Lifting and Rejuvenation.

BACKGROUND

This study aimed to evaluate the efficacy and biocompatibility of various absorbable threads from Hans BioMed for facial lifting in a Sprague Dawley rat model, focusing on collagen production, inflammatory responses, and overall skin remodeling.

METHODS

Six types of absorbable threads, PCL, PDO, PDLLA, PLCL, and two P4HB variants (55 and 90% elongation) from Hans BioMed, were analyzed using histological, immunohistochemical, and molecular methods for observation, including 1, 2, 4, and 8 weeks post-thread insertion. Total 140 rats were used with 20 rats for each thread group, in which five rats for each time point.

RESULTS

Firstly, inflammatory markers, including TNF-α and IL-6, peaked at 1 week and subsided significantly by 8 weeks, confirming the safety profile of all threads. The overall results demonstrated that all threads induced collagen formation and reduced inflammation over time. Notably, collagen 1 levels in all testing groups steadily increased from 2 to 8 weeks, complemented by reduced metalloproteinase expression, indicating preserved collagen stability, observed in Western Blotting. Additionally, RT-PCR highlighted increased expression of collagen-related genes and elevated TGF-β and α-SMA levels, suggesting enhanced skin remodeling capabilities.

CONCLUSION

All tested absorbable threads promoted collagen formation and showed minimal response to inflammation over time. The findings provide a foundation for developing advanced thread-lifting products, offering improved skin elasticity, firmness, and collagen synthesis outcomes.

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