Novel Sodium Channel Inhibitor From Leeches
Research article published in Frontiers in pharmacology (2018)
Abstract
Considering blood-sucking habits of leeches from surviving strategy of view, it can be hypothesized that leech saliva has analgesia or anesthesia functions for leeches to stay undetected by the host. However, no specific substance with analgesic function has been reported from leech saliva although clinical applications strongly indicated that leech therapy produces a strong and long lasting pain-reducing effect. Herein, a novel family of small peptides (HSTXs) including 11 members which show low similarity with known peptides was identified from salivary glands of the leech Haemadipsa sylvestris. A typical HSTX is composed of 22-25 amino acid residues including four half-cysteines, forming two intra-molecular disulfide bridges, and an amidated C-terminus. HSTX-I exerts significant analgesic function by specifically inhibiting voltage-gated sodium (NaV) channels (NaV1.8 and NaV1.9) which contribute to action potential electrogenesis in neurons and potential targets to develop analgesics. This study reveals that sodium channel inhibitors are analgesic substances in the leech. HSTXs are excellent candidates or templates for development of analgesics.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Considering blood-sucking habits of leeches from surviving strategy of view, it can be hypothesized that leech saliva has analgesia or anesthesia functions for leeches to stay undetected by the host.
Why This Matters for Hirudotherapy
This study identified a novel family of 11 small peptides (HSTXs) from the salivary glands of the leech Haemadipsa sylvestris and demonstrated that HSTX-I produces analgesic effects by specifically inhibiting voltage-gated sodium channels NaV1.8 and NaV1.9, which are key targets in neuronal pain signaling. The findings are directly relevant to hirudotherapy as they provide a molecular basis for the pain-reducing effects long observed in clinical leech therapy, identifying a specific salivary secretome component responsible for analgesia rather than relying on anecdotal observation alone. This discovery contributes to understanding the pharmacological complexity of leech saliva and highlights HSTXs as potential templates for analgesic drug development. However, the work centers on peptide identification and functional characterization at the molecular level, and its practical implications for clinical hirudotherapy or pharmaceutical translation will require further investigation beyond what is reported here.
Citation
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