Researchers from the University of Notre Dame and the Indiana University School of Medicine have revealed a putative role for the circadian clock in the liver in the development of alcohol-induced hepatic steatosis, or fatty liver disease.
Hepatic steatosis is the abnormal accumulation of fats in the cells of the liver, and is linked to disturbed control of fat metabolism. Alcohol-induced liver steatosis is produced by excessive alcohol consumption and is linked to hepatitis, or inflammation of the liver. It can be a precursor to an even more serious illness, liver cirrhosis, which includes scarring of the liver. Ten percent to 35 percent of chronic heavy drinkers develop alcoholic hepatitis, and it is the main cause of liver disease in Western countries.
The team, led by associate professors Giles Duffield, from Notre Dame's Department of Biological Sciences and Eck Institute for Global Health, and Suthat Liangpunsakul from the Indiana University School of Medicine's Department of Medicine, Division of Gastroenterology and Hepatology, is interested in the molecular genetic basis for the molecular clock and liver steatosis.
The study, using molecular biological approaches and long-term alcohol feeding of experimental mice, reveals that the development of liver steatosis produced by alcohol abuse is intertwined with disturbances of the normal operation of the 24-hour clock system located in the cells of the liver. Importantly, this change in the liver clock seems to occur independently from the master clock system located in the brain.
The circadian clock regulates 24-hour rhythms in biochemistry, physiology and behavior, and its normal operation and appropriate synchronization to the external world, especially the alternating cycle of day and night, is critical to maintaining a normal healthy state. Disturbances of the clock have been linked to mental health disorders, to metabolic disease including obesity and diabetes, and
|Contact: Giles Duffield|
University of Notre Dame