Kelmer Bracht A, Alvarez M, Bracht A
Biochem Pharmacol. 1985 Mar 15;34(6):873-82. doi: 10.1016/0006-2952(85)90769-5.
The effects of several natural products extracted from the leaves of Stevia rebaudiana on rat liver mitochondria were investigated. The compounds used were stevioside (a non-caloric sweetener), steviolbioside, isosteviol and steviol. Total aqueous extracts of the leaves were also investigated. S. rebaudiana natural products inhibited oxidative phosphorylation, ATPase activity NADH-oxidase activity, succinate-oxidase activity, succinate dehydrogenase, and L-glutamate dehydrogenase. The ADP/O ratio was decreased. Substrate respiration (state II respiration) was increased at low concentrations (up to 0.5 mM) and inhibited at higher concentrations (1 mM or more). In uncoupled mitochondria, inhibition of substrate respiration was the only effect observed. Net proton ejection induced by succinate and swelling induced by several substrates were inhibited. Of the compounds investigated, the sweet principle stevioside was less active. It was concluded that, in addition to the inhibitory effects, S. rebaudiana natural products may also act as uncouplers of oxidative phosphorylation. The possible physiologic consequences of the ingestion of stevioside and S. rebaudiana aqueous extracts are discussed.
研究了从甜叶菊叶片中提取的几种天然产物对大鼠肝脏线粒体的影响。所使用的化合物有甜菊糖苷（一种无热量甜味剂）、甜菊双糖苷、异甜菊醇和甜菊醇。还研究了叶片的总水提取物。甜叶菊天然产物抑制氧化磷酸化、ATP酶活性、NADH氧化酶活性、琥珀酸氧化酶活性、琥珀酸脱氢酶和L-谷氨酸脱氢酶。ADP/O比值降低。在低浓度（高达0.5 mM）时底物呼吸（状态II呼吸）增加，而在较高浓度（1 mM或更高）时受到抑制。在解偶联的线粒体中，观察到的唯一作用是底物呼吸受到抑制。琥珀酸诱导的净质子排出和几种底物诱导的肿胀受到抑制。在所研究的化合物中，甜味成分甜菊糖苷的活性较低。得出的结论是，除了抑制作用外，甜叶菊天然产物还可能作为氧化磷酸化的解偶联剂。讨论了摄入甜菊糖苷和甜叶菊水提取物可能产生的生理后果。
