Biological Effects of Tryptophol, Tryptophol Acetate and Tyrosol Acetate

Background/Objectives: Tryptophol and tyrosol are prominent secondary metabolites with diverse biological activities. Acetylation has been proposed as a strategy to modify the physicochemical properties of these compounds. Despite the proven neuroprotective and adaptogenic activity of tyrosol, in vivo studies, particularly concerning the anxiolytic effects of its acetylated forms, are currently limited. Materials and Methods: This study aimed to compare the behavioral effects of tryptophol, tryptophol acetate, and tyrosol acetate in mice using the chloral hydrate sleep model, the Open Field Test (OFT), and the Forced Swim Test (FST). Results: In the chloral hydrate sleep model, both tryptophol acetate and tyrosol acetate (100 mg/kg, i.g.) significantly prolonged sleep duration without affecting sleep latency, whereas none of the tested compounds induced sleep after single administration (100 mg/kg, i.p.). In the OFT, tyrosol acetate (100 mg/kg, i.g.) significantly increased exploratory activity, as reflected by increased time spent in the central zone and number/duration of verticalizations, indicating an anxiolytic-like behavioral profile. In the FST, tyrosol acetate (100 mg/kg, i.g.) significantly reduced immobility time, suggesting an effect on behavioral responses to acute inescapable stress. Conclusions: Overall, the tested compounds exhibited distinct behavioral profiles, with tyrosol acetate producing the most consistent behavioral effects across the experimental models. These findings suggest that acetylation modifies the neuropharmacological properties of naturally occurring aromatic alcohols and support further investigation of tyrosol acetate, including studies of its mechanisms of action and evaluation in additional anxiety-specific behavioral models.