Fatty liver disease is a rapidly increasing health concern for both humans and animals. A recent discovery made by researchers at NSAC may help identify targets for effective ways of preventing or treating the development of a fatty liver.

“These results were surprising in that they provide the first evidence for the activation of the fat synthesis pathway in mink with fatty liver”, says Kirsti Rouvinen-Watt, “It will be very interesting to see if this interferes with other physiological processes in the body and how it may impact the liver’s ability to cope with the excess fat.”

Fatty liver may develop due to several causes. Of these, lifestyle related factors such as a diet high in fat and rapid mobilization of body fat during weight loss are the most common.

Dr. Rouvinen-Watt and her research team, using the mink as a model animal, has discovered new pathophysiological mechanisms that contribute to the progression of fatty liver disease in mink, a strict carnivore.

The team has shown that while the initial accumulation of liver fat is a result of the release of fatty acids from fat deposits, the liver also makes new fat which further increases the liver lipid load. Following the initial accumulation of excess fat in the liver cells, a transformation of the liver tissue takes place. As a result, the liver begins to turn on genes that are normally expressed in the fatty tissue and begins to produce more fat. This increases the severity of fatty liver disease in two ways; firstly by further increasing the amount of fat within the liver, but it may also inhibit the burning of fat for energy purposes.

Mink are at risk of developing fatty liver several times in their production cycle: during the fall when they deposit body fat in preparation for winter, during winter when slimming down in preparation for breeding and again during lactation when fat is mobilized for milk production for the young.

The results of this research will be very useful to the agricultural sector in Nova Scotia, as mink is currently the number one agricultural export of the province, bringing in over $100 million in annual revenue. This new understanding of fatty liver development is also highly beneficial to the human health sector as the incidence of non-alcoholic fatty liver disease is rapidly increasing together with the associated metabolic syndrome, obesity and Type II diabetes.

The team also includes research assistant Lora Harris, recent NSAC M.Sc. graduates Morag Dick and Catherine Pal and Sha Lei, a visiting Ph.D. student from China, together with their Finnish collaborators Dr. Petteri Nieminen and Dr. Anne-Mari Mustonen. Results of this research are reported in the British Journal of Nutrition.

View the complete paper online.