American Society of Hirudotherapy

Investigating the therapeutic potential of medical leech and leech saliva extract in flap survival: an experimental study using rats

Preclinical study published in Journal of Complementary & Integrative Medicine (2025)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Preclinical (animal)Clinical TrialsSalivary PharmacologyÜnal K et al. · Journal of complementary & integrative medicine, 2025

Abstract

OBJECTIVES: Medicinal leeches have long been recognized for the bioactive compounds present in their saliva. These compounds have been of interest due to their potential therapeutic properties. This research aimed to explore the impact of both medicinal leech application and the application of medicinal leech saliva extract on wound healing in a rat model with a dorsal random flap in vivo. METHODS: In this in vivo study, a dorsal random skin flap model was created in female Wistar albino rats. Rats were randomly assigned to three groups: control (flap only), medicinal leech therapy (MLT), and leech saliva extract (LSE) injection. Histological, immunohistochemical (VEGF), and ELISA-based biochemical analyses were performed to assess wound healing parameters on postoperative day 7. RESULTS: The flap necrosis area (%) in Group II and Group III was significantly lower than the control group (p<0.05). Vascular Endothelial Growth Factor (VEGF) (+) cell (%), neovascularisation, epithelial regeneration, and granulation tissue thickness in Group II and Group III were significantly higher than the control group (p<0.05). Also, inflammatory cells in group III were substantially lower than in the control group (p<0.05). CONCLUSIONS: To our knowledge, this study is the first in the literature to examine the effect of medicinal leech extract injection in the flap model. These findings emphasize the potential therapeutic benefits of medicinal leeches and their saliva extract in promoting efficient wound healing, with implications for future clinical applications.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeJournal Article
Indexed MeSH termsAnimalsSalivaFemaleRats, WistarWound HealingLeechesSurgical FlapsVascular Endothelial Growth Factor ARatsLeeching

Summary

Rat dorsal-flap experimental study comparing intact leech application, topical leech saliva extract, and control on flap survival. Both intact MLT and topical extract improved viable area versus control via enhanced microcirculation and angiogenesis.

Why This Matters for Hirudotherapy

This experimental in vivo study examined the impact of medicinal leech therapy (MLT) and leech saliva extract (LSE) injections on wound healing in a rat dorsal random skin flap model. Both MLT and LSE significantly reduced flap necrosis and increased VEGF-positive cells, neovascularization, epithelial regeneration, and granulation tissue thickness compared to controls, with LSE additionally lowering inflammatory cells. The authors conclude these findings emphasize potential therapeutic benefits of medicinal leeches and their saliva extract in promoting efficient wound healing. The primary limitation is that these results derive from an animal model; the abstract notes only 'implications for future clinical applications' and does not confirm human efficacy.

Citation

Investigating the therapeutic potential of medical leech and leech saliva extract in flap survival: an experimental study using rats.

Ünal K et al. · Journal of complementary & integrative medicine, 2025

Added to ASH library: May 27, 2026 · Site last updated: June 18, 2026

This website provides educational information and does not constitute medical advice, diagnosis, or treatment recommendations. Medicinal leech therapy carries clinically meaningful risks and should be performed only by qualified clinicians under institutionally approved protocols. FDA 510(k) clearance for medicinal leeches is limited to specific indications; investigational and off-label discussions are labeled accordingly. For patient-specific guidance, consult a qualified healthcare provider.