Bioactivity-Guided isolation of β-Sitosterol and Some Fatty Acids as Active Compounds in the Anxiolytic and Sedative Effects of Tilia americana var. mexicana

Abstract

Tilia species have been used as anxiolytics for many years. In a previous study anxiolytic-like effects of a hexane extract of Tilia americana var. mexicana inflorescences were observed in experimental models in mice. To get additional insights into the neuroactive actions of this particular Tilia species, in this study we report a bioactivity guided-fractionation of the extract and separation by column chromatographic methods to isolate three fatty acids and a triterpene identified as beta-sitosterol as major constituents. Our results revealed that the crude extract at 10 and 30 mg/kg I. P. and some pooled fractions at the same dosages potentiated sodium pentobarbital-induced sleeping time and caused a significant increase in the time spent at the open-arm sides in the plus-maze test. A reduction in the exploratory behavioral pattern manifested as ambulatory activity, as well as head dipping and rearing tests was also observed. Further fractionation and purification yielded four major fractions containing fatty acids and beta-sitosterol as the active compounds. A dose-response curve of beta-sitosterol in the range 1 to 30 mg/kg doses indicated that this compound produced an anxiolytic-like action from 1 to 10 mg/kg and a sedative response when the dose was increased to 30 mg/kg, these effects resemble those produced by diazepam (0.1 mg/kg). Our results suggest that hexane extract of Tilia americana var. mexicana produces depressant actions on the central nervous system, at least in part, because of the presence of beta-sitosterol and some fatty acids that remain to be identified.

Anti-ulcer activity of Cyrtocarpa procera analogous to that of Amphipterygium adstringens, both assayed on the experimental gastric injury in rats

“…␤-sitosterol has also been described to have activity as cytotoxic (Nguyen et al, 2004;Matos et al, 2006), antioxidant (Vivancos and Moreno, 2005;Ai-li and Changhai, 2006), anti-inflammatory (Gupta et al, 1980;Gómez et al, 1999) antihyperglycemic (Ortiz-Andrade et al, 2006), sedative and anxiolytic (Aguirre-Hernández et al, 2007) and gastro-protective (Navarrete et al, 2002). With regard to ␤-amyrin, this compound has been described as possessing anti-inflammatory, antinociceptive, and cytotoxic (Oliveira et al, 2004) qualities.…”

Flavonoids from Tilia americana with anxiolytic activity in plus-maze test

“…By means of intraperitoneal (i.p.) administration, the animals showed a decrease of spontaneous motor activity and toxic signs (Aguirre-Hernández et al, 2007a); biological effects were attributed to non-polar compounds (Aguirre-Hernández et al, 2007b). Several populations of this species gathered in the U.S. present metabolic pattern differences: species originating in southern areas contain quercetin-3-O-glucoside and quercetin-1,3,-O-diglucoside, while these glycosyl flavonoids were not detected in species from northern regions (Hockok and Anway, 1972).…”

Interactions of a standardized flavonoid fraction from Tilia americana with Serotoninergic drugs in elevated plus maze

“…In the traditional medicine around the world, Tilia genus species (Tiliaceae Family) has been used for its tranquilizing properties (Viola et al, 1994;Coleta et al, 2001;Aguirre-Hernández et al, 2007a, 2007bPérez-Ortega et al, 2008). This genus has about 25 species; 17 are found in Asia, 6 in Europe and 1 in North of America: Tilia americana (Tang and Zhuge, 1996).…”