The Role of High Fat Diet in Non Alcoholic Fatty Liver Disease (NAFLD)
A Don-Wauchope, H El-Zimaity, A Holloway. McMaster University, Hamilton, ON, Canada; Hamilton Regional Laboratory Medicine Program, Hamilton, ON, Canada
Background: Fatty Liver is an increasing health problem contributing to cirrhosis. The increased incidence is associated with the rise of obesity. To understand its early development we examined the development of fatty liver from high fat diet in Wistar Rats.
Design: We introduced high fat feed and normal diet to weaning pups. The high fat diet was selected to simulate the typical western high fat diet (RD Western Diet, Opensource Diets TM). One third of the animals were selected for necropsy at 7 weeks of age after 4 weeks of a high fat diet. The animals were weighed twice a week and at necropsy. The intra-abdominal fat pads were weighed at necropsy. Blood was collected in serum tubes and the liver was sampled for histology and proteomics. At 7 week necropsy a portion of the liver samples were collected after perfusion with 0.9% saline solution.
Results: Thirty-one animals were selected at random for necropsy. Twelve pairs (5 female and 7 male) and 7 individual (6 female and 1 male) animals were processed. The weights of the animals were not significantly different between the high fat and the low fat diet. However, the abdominal fat pads were significantly different (p<0.0003). When analyzed by gender the females showed significant weight gain (p< 0.002) and increase in abdominal fat weight (p<0.001). In contrast, the males only showed a significant increase in abdominal fat (p<0.001). On histology 6 out of 8 of the females on the high fat diet developed fatty liver whereas only 3 of 8 males developed fatty liver (p=0.14). The distribution of fatty change was different to that usually reported with steatosis in zone 1 rather than the zone 3. The findings on histology are shown in table 1.
|Diet||Gender||N||Fat present||Fat Type|
|High Fat||Female||8||6 (p=0.03)||Macrovesicular 6 (p= 0.03)|
|High Fat||Male||8||3 (p=0.08)||Macrovesicular 3 (p= 0.08)|