Objective: The aim of this study was to evaluate the effect of therapeutic ultrasound (TUS) on dermal delivery and therapeutic effect for frostbite of nanogel containing triterpenoids isolated from Ganoderma lucidum (GLT).
Methods: GLT nanosuspension (GLT-NS) was prepared by high pressure homogenization and then suitably gelled to obtain GLT nanogel. The effects of TUS on GLT releasing from GLT nanogel and GLT permeation through the excised rat abdominal skin were evaluated. Moreover, a comparative study was also undertaken between different treatments of frostbite in rats: topical application of GLT nanogel (alone), TUS (alone) and GLT nanogel + TUS (plus).
Results: In the in vitro release study, TUS has no influence on drug release from the nanogel. Results of the in vitro transdermal study indicated that TUS significantly increased the cumulative amount of GLT permeating across and into the skin and reduced the lag time in comparison with passive diffusion (without TUS). As evidenced by the significant increase of wound healing area and the improvement in frostbite, TUS applied with simultaneous treatment method could improve the therapeutic effect of the GLT nanogel for frostbite.
Conclusion: The present study revealed that the TUS can be effectively used to actively enhance topical delivery of GLT from nanogel and improve the therapeutic effect for frostbite in rats.
Keywords: Frostbite treatment; Ganoderma lucidum; nanogel; therapeutic ultrasound; topical application.