May salivary gland secretory proteins from hematophagous leeches reach pharmacologically relevant concentrations in the vertebrate host?

Pharmacology study published in PLoS ONE (2013)

Última actualización: 18 de junio de 2026Revisado por: ASH Editorial Board

Artículo de investigación — revisión de evidenciaReferencia del artículo

Evidence: Research reportFarmacología salivalEnsayos clínicosLemke S et al. · PloS one, 2013

Abstract

Saliva of hematophagous leeches (Hirudo sp.) contains bioactive proteins which allow the leech proper feeding and storage of ingested blood, but may also exert effects in the host. Leech therapy is used to treat many different ailments in humans, although only a small fraction of salivary proteins are characterized yet. Moreover, we do not know whether complete transfer of salivary proteins stored in the unicellular salivary glands in a leech to the host during feeding may generate concentrations that are sufficiently high to affect physiological processes in the host. Our 3D reconstruction of a portion of internal leech tissue from histological sections revealed that one leech contains approx. 37,000 salivary gland cells. Using tissue slices from pig liver and mouse skeletal muscle for reference, we obtained data for protein densities in leech salivary gland cells. As individual salivary cells are voluminous (67,000 µm(3)) and the stored proteins are densely packed (approx. 500 µg/mm(3)), we extrapolated that a single leech may contain up to 1.2 mg of salivary proteins. Analyzing protein extracts of unfed or fed leeches by 2D electrophoresis, we calculated the relative molar amounts of individual salivary proteins in the mass range of 17-60 kDa which may be released from a single leech during feeding. Distribution of these salivary proteins in the host (assumed plasma volume of 5 l) may result in concentrations of individual compounds between 3 and 236 pmol/l. Such concentrations seem sufficiently high to exert biochemical interactions with target molecules in the host.

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

Publication typeJournal Article

Indexed MeSH termsAnimalsDensitometryElectrophoresis, Gel, Two-DimensionalHumansLeechesLiverMiceMicrotomyModels, AnatomicMuscle, SkeletalReference StandardsSalivary Glands

Resumen

Quantitative analysis of leech salivary protein release during feeding to determine whether host-tissue concentrations reach pharmacologically active levels.

Por qué esto importa para la hirudoterapia

Este estudio empleó reconstrucción 3D del tejido interno de la sanguijuela a partir de secciones histológicas, mediciones de densidad proteica en tejidos de referencia de hígado de cerdo y músculo esquelético de ratón, y electroforesis 2D de sanguijuelas alimentadas y en ayunas para estimar que una sola sanguijuela Hirudo puede contener hasta 1,2 mg de proteínas salivales, lo que potencialmente generaría concentraciones plasmáticas en el huésped de compuestos individuales entre 3 y 236 pmol/L. Para la hirudoterapia, esto es relevante porque aporta una estimación cuantitativa de si las proteínas salivales bioactivas transferidas durante la alimentación de la sanguijuela podrían alcanzar niveles suficientes para afectar procesos fisiológicos en el huésped; los autores sugieren que estas concentraciones parecen lo bastante altas como para ejercer interacciones bioquímicas con las moléculas diana. Sin embargo, se trata de extrapolaciones basadas en un volumen plasmático asumido (5 L) y en un contenido glandular total estimado —no de concentraciones in vivo medidas durante eventos reales de alimentación— y el estudio no confirma la actividad biológica a estos niveles.