Glycolysis inhibition improves photodynamic therapy response rates for equine sarcoids.

The research article presents a new Photodynamic therapy (PDT) technique for treating equine sarcoids that significantly improves treatment outcomes by combining topical application of 5-aminolevulinic acid (ALA) photosensitiser with glycolysis inhibitor lonidamine.

Background and Objectives

• The study is based on the application of Photodynamic therapy (PDT) as a potential treatment for both veterinary and human dermatological neoplasms, including equine sarcoids. The limitation of PDT lies in the delivery capacity for photosensitiser and light towards lesions that are thicker than 2mm, and antioxidant defenses of tumor cells.

Methodology

• The researchers devised a new PDT method that included a proficient transdermal penetration enhancer solution for 5-aminolevulinic acid (ALA) photosensitiser delivery along with acute topical post-PDT application of glycolysis inhibitor lonidamine.
• This method was tested in vitro, showing significant cell death in sarcoid cells, with an increase in the sensitization of these cells to PDT with each round of treatment.

Results

• In in vivo studies, the combination of ALA PDT followed by a 600 μM dosage of lonidamine produced significant improvements in the treatment outcomes for various types of sarcoids (occult, verrucous, nodular, and fibroblastic), showing a 93% treatment response in 27 sarcoids after one month.
• This was in contrast to PDT using only the ALA, which showed a significantly lower 14% treatment response in 7 sarcoids.

Conclusion

• The study concludes that inhibition of glycolysis can substantially improve PDT response rates for treating equine sarcoids. The results show the potential of the combined use of a glycolysis inhibitor with ALA-PDT to provide a more efficacious treatment option for these conditions.