Amirul Nazhan Ilias1, Intan Safinar Ismail2, Hazilawati Hamzah3, Taznim Begam Mohd Mohidin4, Mohd Faiz Idris5, Mokrish Ajat1. 1. Department of Veterinary Preclinical Science, Faculty of Veterinary Medicine, Universiti Putra Malaysia, 43400 UPM, Selangor, Malaysia. 2. Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, 43400 UPM, Selangor, Malaysia. 3. Department of Veterinary Pathology and Microbiology, Faculty of Veterinary Medicine, Universiti Putra Malaysia, 43400 UPM, elangor, Malaysia. 4. Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia. 5. Pusat Bahasa dan Pengajian Umum, Universiti Pendidikan Sultan Idris, 35900 Tanjong Malim, Perak, Malaysia.
Abstract
BACKGROUND: Rebaudioside A is one of the major diterpene glycosides found in Stevia had been reported to possess anti-hyperlipidemic effects. In this study, we explore the potential cholesterol-regulating mechanisms of Rebaudioside A in the human hepatoma (HepG2) cell line in comparison with simvastatin. METHODS: Cells were incubated with Rebaudioside A at several concentrations (0-10 µM) to determine the cytotoxicity by the MTT assay. Cells were treated with selected dosage (1 and 5 µM) in further experiments. Total cellular lipid was extracted by Bligh and Dyer method and subjected to quantitative colorimetric assay. To illustrate the effect of Rebaudioside A on cellular lipid droplets and low-density lipoprotein receptors, treated cells were subjected to immunofluorescence microscopy. Finally, we investigated the expression of experimental gene patterns of cells in response to treatment. RESULTS: In this study, cytotoxicity of Rebaudioside A was determined at 27.72 µM. Treatment of cells with a higher concentration of Rebaudioside A promotes better hepatocellular cholesterol internalization and ameliorates cholesterol-regulating genes such as HMGCR, LDLR, and ACAT2. CONCLUSION: In conclusion, our data demonstrated that Rebaudioside A is capable to regulate cholesterol levels in HepG2 cells. Hence, we proposed that Rebaudioside A offers a potential alternative to statins for atherosclerosis therapy.
BACKGROUND: Rebaudioside A is one of the major diterpene glycosides found in Stevia had been reported to possess anti-hyperlipidemic effects. In this study, we explore the potential cholesterol-regulating mechanisms of Rebaudioside A in the human hepatoma (HepG2) cell line in comparison with simvastatin. METHODS: Cells were incubated with Rebaudioside A at several concentrations (0-10 µM) to determine the cytotoxicity by the MTT assay. Cells were treated with selected dosage (1 and 5 µM) in further experiments. Total cellular lipid was extracted by Bligh and Dyer method and subjected to quantitative colorimetric assay. To illustrate the effect of Rebaudioside A on cellular lipid droplets and low-density lipoprotein receptors, treated cells were subjected to immunofluorescence microscopy. Finally, we investigated the expression of experimental gene patterns of cells in response to treatment. RESULTS: In this study, cytotoxicity of Rebaudioside A was determined at 27.72 µM. Treatment of cells with a higher concentration of Rebaudioside A promotes better hepatocellular cholesterol internalization and ameliorates cholesterol-regulating genes such as HMGCR, LDLR, and ACAT2. CONCLUSION: In conclusion, our data demonstrated that Rebaudioside A is capable to regulate cholesterol levels in HepG2 cells. Hence, we proposed that Rebaudioside A offers a potential alternative to statins for atherosclerosis therapy.
Entities:
Keywords:
Anti-hypercholesterolemia; HMGCR; Lipid droplets; Low-density lipoprotein; Rebaudioside A