Obesity and overweight are classified using Body Mass Index (BMI), calculated as weight in kilograms divided by height in meters squared. A BMI of 25-29.9 represents overweight, a BMI of 30 or greater represents obesity, while a BMI of 18.5-24.9 is considered normal weight. (Read More: )Being overweight or obese is associated with higher risk of heart disease, stroke, diabetes, cancer and many other diseases.
Now a research from Germany provides new insight into the effects of hunger on the body's metabolic function. The research team has revealed that when mice are hungry, a specific protein is generated and helps to regulate metabolism in the liver. This study appears in the Open Access Journal EMBO Molecular Medicine.
Reducing the number of calories that a person take will help to promote recovery of normal metabolism. Scientists wonder what the molecular mechanism of this process is.
To address this question, the research team investigated how food deprivation influenced genetic activity of liver cell. Using transcript arrays, they identified that diet greatly affected the expression of a specific gene, which encodes the protein GADD45ß, or called Growth Arrest and DNA Damage-inducible. The greater the hunger, the higher GADD45ß levels were.
The team found that the protein GADD45ß plays a key role in regulating the absorption of fatty acids in the liver. In addition, mice experiments showed that lacking the specific gene might increase the risk of fatty liver disease. After the protein was restored, sugar metabolism was improved and liver fat content returned to normal.
The researchers also found the same mechanism in humans. The study could help to understand how hunger impacts metabolism, providing new ways to improve metabolism function.