Brain News: Scientists uncovered that the effects of alcohol intoxication such as slurred speech and poor coordination, are actually due to the breakdown of alcohol products produced in the brain, not in the liver.
Currently, most scientists think that alcohol metabolism occurs in the liver with the help of the enzyme alcohol dehydrogenase, which converts alcohol into acetaldehyde, which is a toxic byproduct and is considered to be responsible for cognitive impairment. Another enzyme called acetaldehyde dehydrogenase 2 (ALDH2), then breaks acetaldehyde into acetate that is not so harmful to the body.
The new study published in the Journal Nature Metabolism examined the role of the brain in alcohol metabolism. They measured the distribution of ALDH2 enzyme in the cerebellum, using magnetic resonance (MR) scanners in both mice and in human tissue. The cerebellum is a brain region that controls balance and motor coordination.
Researchers found that ALDH2 was expressed in the cerebellum, in both human brain tissue, and in living mice. Alcohol-induced cellular and behavioral effects of alcohol were observed in the specific brain regions.
They noted that ALDH2 can convert acetaldehyde into acetate in the brain. Acetate was found to interact with the brain messenger chemical called GABA, which is known to decrease activity in the nervous system causing drowsiness, impaired coordination, and lower normal feelings of inhibition. When ALDH2 was removed from these cells, the mice were resistant to motor impairment induced by alcohol consumption.
There is a need for further research on the human brain to better understand alcohol metabolism and find a potential target for treating alcohol use disorder.
To Know More, You May Refer To:
Shiyun Jin, Qi Cao, Fanghan Yang, Hongying Zhu, Su Xu, Qi Chen, Ziyi Wang, Yuhong Lin, Resat Cinar, Robert J. Pawlosky, Ye Zhang, Wei Xiong, Bin Gao, George F. Koob, David M. Lovinger, Li Zhang. Brain ethanol metabolism by astrocytic ALDH2 drives the behavioural effects of ethanol intoxication. Nature Metabolism, 2021; 3 (3): 337 DOI: 10.1038/s42255-021-00357-z