Carnosine is a dipeptide (2 amino acids) made of beta-alanine and l-histidine joined together by the enzyme, carnosine synthetase. Carnosine is found in liver, brain and skeletal muscles. This study was done to see whether carnosine or histidine can reduce lipid formation in the liver and fat tissue at times of a high fat diet in mice. The result is hepatic steatosis.
Hepatic steatosis, along with high blood fats and obesity, are risk factors for diseases of circulation and metabolism. Treatment to reduce fat formation would likely be of benefit to those with the disease.
The untreated control mice, fed high fat (55% saturated fats) diets, developed increased body weights and high liver triglycerides, high liver cholesterols, high blood levels of insulin and hepatic steatosis. They had increased amounts of epididymal white fat tissue.
In this project, one gram of histidine, alanine or carnosine was added to the drinking water of some of the mice on the high fat diets for 8 weeks. Histidine and carnosine increased the blood levels of histidine, alanine and carnosine. The animals which were given carnosine or histidine had lower body weights, lower triglycerides, lower cholesterols, lower epididymal white fat and less hepatic steatosis than the control animals not treated.
The high fat diet increased blood levels of the enzymes which form fats. Carnosine and histidine reduced the RNA expression of fat-forming enzymes and reduced the blood levels of these enzymes. Histidine and carnosine improved the hyperinsulinemia and the insulin resistance seen with fatty liver in mice.
Chicken and beef are good sources of carnosine. Carnosine can be absorbed with oral intake. Alanine supplementation increases the tissue content of carnosine.
CONCLUSION: Histidine seems to be an effective anti-lipogenic agent. It reduced the fatty liver caused by a high fat diet. There was reduced RNA expression of the enzymes which form fatty acids on either histidine or carnosine supplementation.
NOTE: Hepatic steatosis is sometimes called fatty liver. It is different from the liver disease caused by alcohol intake, but, can lead to liver cirrhosis. Fructose is associated with fatty liver and with kidney disease. Read about fructose and kidney disease.
Alanine is a precursor and a metabolic breakdown product of carnosine. Carnosine is composed of a single molecule of alanine and a molecule of histidine.
Miller, SL, scientist, was first created beta-alanine in 1953 under laboratory conditions. The study was designed to show that volcanic conditions could have created amino acids.