Chronic administration of the soluble non-bacterial fraction of kefir attenuates lipid deposition in LDLr-/- mice

Abstract Background Kefir is obtained by the action of acidic bacteria and yeasts that exist in symbiotic association in kefir grains. Recently, this fermented milk drink has been recommended for the treatment of several clinical conditions, such as inflammatory, gastrointestinal and/or cardiovascular related-diseases. However, its effects on atherosclerosis are not yet clear. Then, our hypothesis was that chronic treatment with a soluble, non-bacterial fraction of kefir could reduce the progression of atherosclerosis in LDLr-/- mice. Methods LDLr-/- mice were divided into 4 groups. 1) The ND group received a normal diet without treatment. 2). The HD group received a high-fat diet without treatment. 3). The HD-Milk group received a high-fat diet and was orally treated with the vehicle (milk - 22 mL/kg). 4) The HD-Kefir group received a high-fat diet and was orally treated with soluble non-bacterial fraction of kefir (22 mL/kg) for 4 weeks. At the end of experiment, blood was collected to measure cholesterol and cytokines, and the aorta was collected to evaluate the lipid deposition by en face analysis. Results The soluble, non-bacterial fraction of kefir reduced lipid deposition (p