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bioRxiv · 10.1101/2023.04.10.536237

Palmitoylethanolamide shows limited efficacy in controlling cerebral cryptococcosis in vivo

Munzen, M. E.·Reguera Gomez, M.·Hamed, M.·Enriquez, V.·Charles-Nino, C. L.·Dores, M. R.·Alvina, K.·Martinez, L. R.
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Abstract

Cryptococcus neoformans (Cn) is an encapsulated neurotropic fungal pathogen and the causative agent of cryptococcal meningoencephalitis (CME) in humans. Recommended treatment for CME is Amphotericin B (AmpB) and 5-fluorocytosine (5-FC). Though effective, AmpB has displayed numerous adverse side effects due to its potency and nephrotoxicity, prompting investigation into alternative treatments. Palmitoylethanolamide (PEA) is an immunomodulatory compound capable of promoting neuroprotection and reducing inflammation. To investigate the efficacy of PEA as a therapeutic alternative for CME, we intracerebrally infected mice with Cn and treated them with PEA or AmpB alone or in combination. Our results demonstrate that PEA alone does not significantly prolong survival nor reduce fungal burden, but when combined with AmpB, PEA exerts an additive effect and promotes both survivability and fungal clearance. However, we compared this combination to traditional AmpB and 5-FC treatment in a survivability study and observed lower efficacy. Overall, our study revealed that PEA alone is not effective as an antifungal agent in the treatment of CME. Importantly, we describe the therapeutic capability of PEA in the context of Cn infection and show that its immunomodulatory properties may confer limited protection when combined with an effective fungicidal agent.

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Munzen, M. E., Reguera Gomez, M., Hamed, M., Enriquez, V., Charles-Nino, C. L., Dores, M. R., Alvina, K., Martinez, L. R.. 2023-04-12. Palmitoylethanolamide shows limited efficacy in controlling cerebral cryptococcosis in vivo. https://doi.org/10.1101/2023.04.10.536237

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