Sheik Mohideen S, Yamasaki Y, Omata Y, Tsuda L, Yoshiike Y. Nontoxic singlet oxygen generator as a therapeutic candidate for treating tauopathies. Sci Rep. 2015 Jun 1;5:10821. PMID: 26027742; PMCID: PMC4450544.
From the abstract: "Methylene blue (MB) inhibits the aggregation of tau, a main constituent
of neurofibrillary tangles. However, MB's mode of action in vivo is not
fully understood. MB treatment reduced the amount of sarkosyl-insoluble
tau in Drosophila that express human wild-type tau. MB concurrently
ameliorated the climbing deficits of transgenic tau flies to a limited
extent and diminished the climbing activity of wild-type flies. MB also
decreased the survival rate of wild-type flies. Based on its
photosensitive efficacies, we surmised that singlet oxygen generated
through MB under light might contribute to both the beneficial and toxic
effects of MB in vivo. ...
Our findings indicate that singlet oxygen generators with little
toxicity may be suitable drug candidates for treating tauopathies."