We've written several times now about maizinol, an extract from the leaves of young corn plants that lowers cortisol levels and improves sleep. Today we read an animal study that demonstrates maizinol's mechanism of action. It's extremely interesting.

Study
In 2024, Korean scientists published an animal study in Food Bioscience in which they gave mice either no supplements or a low or high dose of maizinol daily for four weeks. If the mice in the experimental groups had been adults weighing 70 kilograms, they would have received approximately 250 or 500 milligrams of maizinol daily.

The researchers were affiliated with Korea University and Naturetech, the company that developed maizinol. In their publication, the researchers still refer to this extract as UP165.

Results
As in the trials we discussed earlier, supplementation improved the mice's sleep. Maizinol extended the total sleep duration and altered sleep architecture. The duration of slow-wave or delta sleep increased, while REM sleep remained unchanged.

Delta sleep is the sleep phase during which the body focuses on tissue repair, activates the immune system, and initiates the production of anabolic hormones such as growth hormone.

Click on the figures and tables below for a larger version.

Supplementing with maizinol increased the number of receptors for melatonin, serotonin, and GABA. This is interesting. Maizinol contains substances like 6-MBOA, which can bind to melatonin receptors.

Melatonin administration itself ultimately reduces the production of these receptors, particularly type 1A receptors, in the long run. These receptors are involved in falling asleep after taking melatonin. But maizinol does the exact opposite.

Due to the negative effect on receptor production, a dose of melatonin is only effective temporarily. Ultimately, the dosage needed to fall asleep faster will need to be increased. Therefore, maizinol likely does not have this disadvantage.

Finally, maizinol supplementation increased the melatonin concentration (plus that of serotonin and GABA) in the test animals. This is also striking. You would expect a substance that mimics the effect of melatonin to lower melatonin concentrations.