Rebaudioside A

Rebaudioside A is an orally effective steviol glycoside with high sweetness. Rebaudioside A acts as an inhibitor of α-glucosidase with an IC₅₀ value of 35.01 μg/mL. Rebaudioside A increases the ATP/ADP ratio in β cells in a glucose-dependent manner, thereby inhibiting KATP channels, leading to membrane depolarization, calcium influx, and ultimately stimulating insulin secretion. Rebaudioside A activates the SREBP signaling pathway by inhibiting HMGCR, the rate-limiting enzyme in cholesterol synthesis, resulting in increased expression of LDLR on the cell surface, thus promoting the uptake of LDL-C in the blood. Rebaudioside A can be used for studies on blood glucose and lipid regulation as well as anti-obesity^{[1][2][3][4][5]}. In Vitro:Rebaudioside A (0.1 pM-0.1 μM; 1 h) stimulates insulin secretion from MIN6 cells in a glucose-dependent manner under the condition of 16.7 mM glucose^[1].
Rebaudioside A (1 nM; 2 h) significantly increases the ATP/ADP ratio in isolated mouse islets under the condition of 16.7 mM glucose^[1].
Rebaudioside A (1 nM) inhibits K_ATP channel conductance in dispersed mouse β-cells in a glucose-dependent manner, exerting significant inhibitory effects at a glucose concentration of 16.7 mM but showing no effect at 3.3 mM glucose^[1].
Rebaudioside A (1-10 μM; 24 h) exhibits dose-dependent cytotoxicity in HepG2 cells, with an IC₅₀ of 27.72 μM^[3].
Rebaudioside A (1-5 μM; 24 h) increases the total cellular cholesterol level in HepG2 cells treated with 5 μM lipid stimulant^[3].
Rebaudioside A (1-5 μM; 24 h) upregulates LDLR expression and enhances lipid droplet formation in HepG2 cells treated with lipid stimulants, with a more potent effect observed at 5 μM than at 1 μM^[3].
Rebaudioside A (1-5 μM; 24 h) significantly regulates cholesterol-regulating genes in HepG2 cells by downregulating HMGCR and upregulating LDLR and ACAT2, with a more potent effect observed at 5 μM than at 1 μM^[3]. In Vivo:Rebaudioside A (50 mg/kg; p.o.; 5 days per week; 4 weeks) reduces total adipose tissue weight by 21.87% and perirenal adipocyte area by 8.9% in ob/ob mice^[4].