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Arbiser, J. L.

Publications and source records attributed to Arbiser, J. L..

2 recordsLinked to original sources

Hexafluoro slows retinal degeneration and improves visual function in zebrafish models of Usher syndrome 1F

Usher syndrome is the leading genetic cause of deafblindness, affecting hundreds of thousands of people worldwide. The deafness can be addressed with hearing aids or cochlear implants, but there is currently no treatment for the vision loss, which is due to progressive degeneration of retinal photoreceptors. Studies in animal models of Usher syndrome have shown that photoreceptor degeneration is exacerbated by exposure to bright light, and other studies have shown that light-induced photostress reduces mitochondrial function. We previously synthesized hexafluoro and showed that it is a potent Sirt3 activator that promotes mitochondrial respiration. Here we examined the efficacy of hexafluoro as a potential therapeutic for treatment of vison loss in a zebrafish model of Usher syndrome type 1F, which exhibits early and severe vision defects along with vestibular dysfunction as seen in Usher type 1 pathology. We find that hexafluoro improves visual function, reduces photoreceptor degeneration, and protects the retina against exposure to bright light in this USH1F model.

neuroscience↗

Honokiol inhibits SARS-CoV-2 replication in cell culture

SARS-CoV-2 emerged in 2019 and since its global spread has caused the death of over 6 million people. There are currently few antiviral options for treatment of COVID-19. Repurposing of known drugs can be a fast route to obtain molecules that inhibit viral infection and/or modulate pathogenic host responses. Honokiol is a small molecule from Magnolia trees, for which several biological effects have been reported,, including anticancer and anti-inflammatory activity. Honokiol has also been shown to inhibit several viruses in cell culture. In this study, we show that honokiol protected Vero E6 cells from SARS-CoV-2-mediated cytopathic effect with an EC50 of 7.8 {micro}M. In viral load reduction assays we observed that honokiol decreased viral RNA copies as well as viral infectious progeny titers. The compound also inhibited SARS-CoV-2 replication in the more relevant A549 cells, expressing ACE2 and TMPRSS2. A time-of-addition assay showed that honokiol inhibited virus replication even when added post infection, suggesting it acts at a post-entry step of the replication cycle. Honokiol was also effective against more recent variants of SARS-CoV-2, including omicron and it inhibited other human coronaviruses as well. Our study suggests that honokiol is an interesting molecule to evaluate in animal studies and clinical trials to investigate its effect on virus replication and pathogenic (inflammatory) host responses.

microbiology↗