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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. Conclusions: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.

As of today, no literature has been reported on the efficacy of stevia on lipid regulations conducted in vitro. Thus, the current study was focusing on the potential of Stevia rebaudiana bertoni as an anti-hypercholesterolemia substitute in limiting the de novo cholesterol synthesis in Hep-G2 cell line. The cytotoxicity and lipid internalization effects of stevia on Hep-G2 cells were assessed quantitatively and qualitatively in this study. As evaluated by MTT assay, commercialized stevia (0.5-20.0 mg/ml) and stevioside (1.0-10 µM) inhibited Hep-G2 cells viability in a dose-dependent manner for 24 hours. IC50 was detected at 8.68 mg/ml (commercialized stevia) and 10.91 µM (stevioside). From the assay, suitable concentrations were chosen to study the effect of stevia on cholesterol internalization in Hep-G2 cells supplemented with exogenous lipids. Cholesterol quantification assay revealed that high concentration commercialized stevia and stevioside promoted significant cholesterol internalized in Hep-G2 cells as compared to simvastatin. Finally, immunofluorescent microscopy assessment was done to qualitatively observe the formation of lipid droplets and low-density lipoprotein receptor in relation to total cholesterol extracted. The microphotographs of immunofluorescent microscopy were in parallel to results obtained from the cholesterol quantification assay which further revealed the effect of stevia as a potential anti-hypercholesterolemia agent.

Background and Aim: The value of the pet food industry, which is majorly the prescribed diet, exponentially increased over the years due to increased awareness among pet owners to provide a healthy lifestyle for their pets. However, several factors such as aroma, flavor, texture, and shape of prescribed diets greatly influenced the palatability in cats. Therefore, this study aimed to determine the palatability of the prescribed diet for domestic shorthair (DSH) cats. Materials and Methods: The two-bowl method was employed to determine the palatability of prescribed diets on five DSH cats for 6 days. Furthermore, the four types of prescribed diet assessed in this study were struvite, renal, hypersensitivity, and intestinal. Furthermore, the pet food palatability was analyzed using “First Approached,” “First Consumed,” “Total Consumption,” and “Intake ratios.” Results: Our findings revealed that “Total Consumption” and “Intake Ratios” were significantly different in struvite, renal, and intestinal diets compared to the hypersensitivity diet. In addition, this result indicates that the hypersensitivity diet is the most unpalatable compared with other diets. Conclusion: A detailed investigation of the diet ingredients showed that a hypersensitivity diet lacks herbs and spices than the other diets. Therefore, these ingredients lacking in the hypersensitivity diet influence the palatability of pet foods.

Lipids such as glyceryl monooleate, phosphatidylcholine, and monoglyceride (CITREM) possess an amphipathic property that allows them to self-assemble into a complex internal structure when interacting with an aqueous solution. Since amphiphilic molecules possess hydrophilic heads and lipophilic tails, hydrophobic effects cause the spontaneous activity of the molecular rearrangement. The self-organization of the molecules often results in the phases of lipid polymorphism, for example microemulsion, inverse bicontinuous cubic (Q2), discontinuous hexagonal (H2), and micellar cubic (I2) Fd3m. Interestingly, these lamellar and non-lamellar phases have been applied in the development of nanocarriers for drug delivery due to their ability to provide a sustained drug release system, better drug bioavailability, and improved overall treatment. However, the attention that they are receiving from their application is not comparable to our understanding of the mechanisms involved in their synthesis. Elucidation of the spontaneous process helps in predicting and tuning the internal structure of an amphiphilic molecule to suit its application. Therefore, this review discusses the formation of lipid polymorphism from the thermodynamic point of view, critical packing parameter, and modified stalk theory.