Comparison research on the therapeutic effects of botulinum toxin type A and stromal vascular fraction gel on hypertrophic scars in the rabbit ear model.

BACKGROUND AND

OBJECTIVES

Botulinum toxin type A (BTA) is often used for wrinkles and muscle convulsive diseases due to its blocking of the transmission of nerve impulses. Stromal vascular fraction gel (SVF-gel) prepared from adipose tissue has novel effects on skin depression and poor texture. Both BTA and SVF-gel are proved to possess anti-scar potential. This study aimed to assess and compare their therapeutic effects on hypertrophic scars.

MATERIALS AND

METHODS

The rabbit ear scar model was established and treated with BTA and SVF-gel, alone or in combination. Gross evaluation using Manchester Scar Scale (MSS) was conducted immediately, 4 and 8 weeks after initial treatment. After tissue sample harvest, histological and Western blot analyses were performed.

RESULTS

All the treatments alleviated scar hyperplasia in different degrees by inhibiting fibroblast activation (Ki-67, α-SMA), tissue inflammation (CD45, IL-1β) and the transforming growth factor-β1 (TGF-β1)/Smad3 pathway. Despite an excellent anti-inflammatory effect, improvement of scar appearance and pathological characteristics in SVF-gel-contained groups was not as good as that in BTA-only group, which might be related to the retention of M2-type macrophages (CD163 +) and partial maintenance of TGF-β1 expression.

CONCLUSION

Our data suggest that BTA has better anti-scar efficacy than SVF-gel, and the combination of these two treatments shows no obvious combinatorial effect.