Yaren Kayabaşı1, Oytun Erbaş1,2

1Institute of Experimental Medicine, Gebze-Kocaeli, Turkey
2Department of Physiology, Medical Faculty of Demiroğlu Bilim University, Istanbul, Turkey

Keywords: Alzheimer’s disease, antifungal, antimalarial therapy, candidiasis, electron transport chain, glutathione reductase, methylene blue, mitochondrial dysfunction, tau proteins.


Methylene blue (MB), a blue-colored aniline-based dye that was first developed for the dyeing of cotton, is a phenothiazine derivative that is soluble in water and organic solvents. Its reduced form, leucomethylene blue, is colorless and has a regulatory effect on the redox cycle. This feature allows it to be used in malarial therapy by inducing glutathione reductase (GR), an enzyme of glutathione metabolism. Malaria is a disease characterized by repeated growth cycles of Plasmodium group parasites in erythrocytes and changes in glutathione metabolism. Methylene blue was recognized as an antimalarial agent when it was observed that it reduced reactive oxygen species (ROS) by inhibiting Plasmodium falciparum glutathione reductase and by selectively inducing oxidative stress. It has also been observed that MB can reduce factors that cause aging and Alzheimer’s disease, such as the accumulation of tau proteins in plaques, mitochondrial dysfunction, and ROS increase due to disorders in the electron transport chain (ETC). Methylene blue has been used in Alzheimer's treatment, considering its features of tau protein inhibition, anti-ROS antioxidant properties, and ability to regulate ETC. Methylene blue, known for its antimalarial and antioxidant effects, has also been used in the treatment of Candida infections as an antifungal agent. In candidiasis infections, MB is aimed to cause mitochondrial dysfunction in yeast and treat the patient. In this review, the history of MB as an antimalarial, antioxidant and antifungal agent; malaria, Alzheimer's, and its role in the treatment of candidiasis. In this review, the history of MB and its role as an antimalarial, antioxidant, and antifungal agent in the treatment of malaria, Alzheimer's, and candidiasis are discussed.

Conflict of Interest

The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.

Financial Disclosure

The authors received no financial support for the research and/or authorship of this article.