Medicinal Leech CNS as a Model for Exosome Studies in the Crosstalk between Microglia and Neurons
Basic science / preclinical published in International journal of molecular sciences (2018)
Abstract
In healthy or pathological brains, the neuroinflammatory state is supported by a strong communication involving microglia and neurons. Recent studies indicate that extracellular vesicles (EVs), including exosomes and microvesicles, play a key role in the physiological interactions between cells allowing central nervous system (CNS) development and/or integrity. The present report used medicinal leech CNS to investigate microglia/neuron crosstalk from ex vivo approaches as well as primary cultures. The results demonstrated a large production of exosomes from microglia. Their incubation to primary neuronal cultures showed a strong interaction with neurites. In addition, neurite outgrowth assays demonstrated microglia exosomes to exhibit significant neurotrophic activities using at least a Transforming Growth Factor beta (TGF-β) family member, called nGDF (nervous Growth/Differentiation Factor). Of interest, the results also showed an EV-mediated dialog between leech microglia and rat cells highlighting this communication to be more a matter of molecules than of species. Taken together, the present report brings a new insight into the microglia/neuron crosstalk in CNS and would help deciphering the molecular evolution of such a cell communication in brain.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Ex vivo and primary-culture studies of medicinal leech CNS show microglia produce abundant exosomes that interact with neurites and promote neurite outgrowth via at least the TGF-β family member nGDF; vesicle-mediated dialogue also occurred with rat cells.
Why This Matters for Hirudotherapy
This study used medicinal leech central nervous system tissue, through ex vivo approaches and primary cultures, to investigate how exosomes produced by microglia communicate with neurons and influence neurite outgrowth. The findings showed that microglia-derived exosomes exhibited significant neurotrophic activity mediated at least partly by a TGF-β family member called nGDF, and that extracellular vesicle-mediated communication occurred between leech microglia and rat cells, suggesting the process is governed more by conserved molecules than by species identity. This work is relevant because it uses medicinal leech tissue to characterize bioactive molecules involved in neural repair and neuroprotection, themes conceptually adjacent to therapeutic interest in leech-derived bioactive compounds. However, the study examines CNS microglia-neuron signaling rather than leech salivary secretions or clinical hirudotherapy, and the neurotrophic effects are demonstrated in culture systems rather than therapeutic contexts; its connection to hirudotherapy is indirect and limited to the leech as a research model.
Citation
Reference (Vancouver style)
Raffo-Romero A, Arab T, Al-Amri IS, Le Marrec-Croq F, Van Camp C, Lemaire Q, et al. Medicinal Leech CNS as a Model for Exosome Studies in the Crosstalk between Microglia and Neurons. Int J Mol Sci. 2018;19(12):4124. doi:10.3390/ijms19124124. PMID: 30572617
Bibliographic details (authors, volume, pages, DOI) are taken from the PubMed record.
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