Methylene Blue

122965-43-9

602-909-3

Methylene Blue hydrate

C16H20ClN3OS

337.9

CN(C)C1=CC2=C(C=C1)N=C3C=CC(=[N+](C)C)C=C3S2.O.[Cl-]

WQVSELLRAGBDLX-UHFFFAOYSA-M

Soluble in water, alcohol, acetic acid, glycerol and chloroform

Green to dark green powder

2-8℃

190ºC

Methylene-Blue1.png

Methylene Blue is an oxidoreduction cyclic compound that can pass through the blood-brain barrier. It belongs to the thiazine class of dyes and has multiple biological activities. It was initially used in the treatment of bacterial dysentery and malaria and is an important representative of modern synthetic dye-based drugs. The research field of Methylene Blue has expanded into areas such as neuroprotection, anti-infection, and anti-tumor, making it a multifunctional compound with extensive potential.

Methylene Blue, as a water-soluble thiazine dye with clear redox activity, its core mechanism of action is to selectively reduce methemoglobin (metHb) through a redox cycle. After entering the body, Methylene Blue is first reduced by NADPH reductase within red blood cells to the reduced form of methylene blue (LMB). LMB acts as an electron donor, reducing Fe³⁺ in metHb to Fe²⁺, allowing the hemoglobin to regain its oxygen-carrying function and itself being oxidized back to methylene blue to complete the catalytic cycle. The entire process does not rely on specific enzyme systems, is rapid in onset, and only acts on metHb, having no effect on normal hemoglobin.

Methylene Blue can be used as a chemical indicator, dye, biological stain and drug. Methylene Blue is approved for use in surgical staining, malaria, methemoglobinemia, etc. Besides, Methylene Blue can also be studied for application in areas such as sepsis and neuroprotection by inhibiting nitric oxide (NO) signaling and regulating mitochondrial function, etc.

Methylene Blue (MB) was the first artificially synthesized drug. Originally used for textile dyeing, it is now widely used in surgical marking, malaria treatment, methemoglobinemia treatment, etc. In recent years, it has been found to have the function of antioxidant, which can improve mitochondrial function and delay aging-related pathological processes.
MB is a reversible redox agent that can interconvert between the oxidized form (blue) and the reduced form (colorless). It is hydrophilic and lipophilic, and can enter biological membranes and mitochondria. The main mechanisms of action are to bypass complexes I and III of the mitochondrial electron transport chain (ETC), reduce the production of ROS, increase cytochrome oxidase activity and ATP synthesis, relieve oxidative stress, and break the vicious cycle between ROS and mitochondrial damage.
In terms of brain aging, MB can cross the blood-brain barrier, improve the mitochondrial function of nerve cells, reduce ROS production, inhibit the inhibition of cytochrome oxidase by nitric oxide (NO), and improve brain metabolism.
In terms of skin aging, MB can delay skin aging by removing ROS, promoting fibroblast proliferation, and increasing collagen and elastin expression. It has also been found to have ultraviolet absorption in a wide range of spectra. The absorption can reduce DNA damage caused by UVB, promote wound healing, and have better anti-aging effects than vitamin C and retinol.
MB has broad application prospects in delaying aging and has a positive impact on the improvement of neurodegenerative diseases, skin aging, and premature aging disorders.

Methylene-Blue2.png

Fig. 1 Effects of Methylene Blue in delaying skin aging. (Xue H.; et al. 2021)

Xue H, et al. The potentials of methylene blue as an anti-aging drug. Cells, 2021, 10(12): 3379.

[{
"question": "What is the solubility profile of Methylene Blue?",
"answer": "Methylene Blue is soluble in water, alcohol, acetic acid, glycerol, and chloroform, offering flexibility for various formulations."
},
{
"question": "How should Methylene Blue be stored?",
"answer": "Store Methylene Blue as a green to dark green powder at 2–8℃ to maintain stability and efficacy."
},
{
"question": "Is Methylene Blue approved for medical use?",
"answer": "Methylene Blue is approved for surgical staining, malaria, and methemoglobinemia, with ongoing research in sepsis and anti-aging."
},
{
"question": "How does Methylene Blue work in methemoglobinemia?",
"answer": "It reduces methemoglobin to functional hemoglobin via a redox cycle, restoring oxygen transport without affecting normal hemoglobin."
}
]