A comparative study on dyslipidaemia inducing diets in various rat strains

Area of Science:

• Animal models
• Lipid metabolism
• Nutritional science

Background:

• Serum lipoprotein lipid composition varies between rat strains.
• Dietary interventions significantly impact lipid profiles.
• Understanding these variations is crucial for metabolic research.

Purpose of the Study:

• To compare serum lipoprotein lipid composition in Fischer 344 (F344), Long-Evans (LE) rats, and their hybrids (FLF1).
• To evaluate the effects of different diets (standard, butter-rich, cholesterol-rich, and a combined modified Hartroft-Sós diet) on lipid profiles over 2, 4, and 8 weeks.
• To assess the suitability of this model for dyslipidemia research and chemoprevention studies.

Main Methods:

• Feeding F344, LE rats, and FLF1 hybrids with four distinct diets for up to 8 weeks.
• Analyzing serum total cholesterol, LDL-cholesterol, HDL-cholesterol, and triglyceride levels.
• Measuring LDL/HDL ratio and PON-1 activity.
• Histopathological examination of the abdominal aorta for lipid deposition.

Main Results:

• The modified Hartroft-Sós diet significantly elevated serum total cholesterol, LDL-cholesterol, HDL-cholesterol, and triglycerides in F344 female rats within two weeks.
• LE male rats showed moderately increased lipid values, while FLF1 female hybrids exhibited profiles closer to their F344 mothers.
• Despite increased LDL/HDL ratio and decreased PON-1 activity, significant aortic lipid deposition was not observed even after two months.

Conclusions:

• The experimental model effectively induces dyslipidemia in F344 female rats using a modified Hartroft-Sós diet.
• This model is suitable for the chemoprevention of dyslipidemia and rapid testing of therapeutic molecules.
• Further research may explore the long-term effects and mechanisms underlying the lack of aortic lipid deposition.