A study will be published on March 21, 2009 in World Journal of Gastroenterology addresses the question. A research group in King Saud University, Kingdom of Saudi Arabia investigated, for the first time, the role of carnitine, a naturally occurring compound that is synthesized mainly in the liver, during the development of hepatocarcinogenesis. Authors of the study reported that carnitine deficiency is a risk factor and should be viewed as a mechanism in hepatic carcinogenesis, and that long-term L-carnitine supplementation prevents the development of liver cancer. Therefore, carnitine supplementation alone or in combination with other natural chemopreventive compounds could be used to prevent, slow or reverse the occurrence of liver cancer.
Chemoprevention is defined as the use of naturally occurring and/or synthetic compounds in cancer therapy in which the occurrence of cancer can be entirely prevented, slowed or reversed. L-carnitine is a naturally occurring compound which is primarily located in mitochondria and possesses potential protective effects against many mitochondrial toxic agents. It is derived from two sources; endogenous synthesis, in the liver and kidney, and from exogenous dietary sources such as red meat and dairy products. L-carnitine is an essential cofactor for the translocation of long chain fatty acids from the cytoplasmic compartment into mitochondria, where beta-oxidation enzymes are located for ATP production. Despite the liver being the main organ responsible for endogenous synthesis of L-carnitine, we were unable to find any studies investigating the role of long-term endogenous carnitine depletion and/or carnitine deficiency during induction of hepatic carcinogenesis.
The research team by Professor Sayed-Ahmed from College of Pharmacy, King Saud University used an experimental model of hepatocarcinogenesis under conditions of carnitine depletion and carnitine supplementation.
In the carnitine-depleted rat model, there were a progressive increase in the activities of liver enzymes as well as massive degenerative changes and evidence of pre-neoplastic lesions in liver tissues including clusters of hepatocytes with atypia and an increased proliferative rate, diffuse bridging fibrosis and nodule formation, bile ducts with marked reactive atypia showing nuclear enlargement, high nuclear/cytoplasmic ratio and prominent nucleoli. Interestingly, L-carnitine supplementation resulted in a complete reversal of the increase in liver enzymes compared to normal values, as well as normal liver histology with unremarkable central vein and no evidence of pre-neoplastic lesions in liver tissues.
Due to the fact that liver cancer is one of the major health problems in the world and a large sector of patients seek medical attention at a relatively late stage which increases the cost of treatment, King Saud University granted Prof. Sayed-Ahmed and his colleagues a research project with the following specific aims: (1) to understand the possible molecular mechanisms whereby carnitine deficiency provokes hepatic carcinogenesis. (2) to understand the relationship between hepatic cancer and its resistance to cancer chemotherapy, and (3) to gain knowledge on the possible mechanisms by which carnitine supplementation alone or in combination with other natural chemopreventive compounds could be used to prevent, slow or reverse the occurrence of liver cancer.
Reference: Al-Rejaie SS, Aleisa AM, Al-Yahya AA, Bakheet SA,Alsheikh A, Fatani AG, Al-Shabanah OA, Sayed-Ahmed MM. Progression of diethylnitrosamine-induced hepatic carcinogenesis in carnitine-depleted rats World J Gastroenterol 2009; 15(11): 1373-1380
Correspondence to: Dr. Mohamed M Sayed-Ahmed, Department of Pharmacology, College of Pharmacy, King Saud University, PO Box 2457, Riyadh 11451, Kingdom of Saudi Arabia. firstname.lastname@example.org Telephone: +966-506065734 Fax: +966-1-14677200