A 20-hydroxyecdysone-enriched fraction from Pfaffia glomerata (Spreng.) pedersen roots alleviates stress, anxiety, and depression in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Pfaffia glomerata roots are widely used in Brazil to treat various pathological conditions, particularly psychological disorders. 20-hydroxyecdysone, a phytosteroid present in the plant, can promote greater body resistance against exogenous and endogenous stressors. The objective of this study was to evaluate the possible neuroprotective effect of a 20-hydroxyecdysone-enriched fraction (20E-EF), obtained from P. glomerata roots, in an acute murine stress model. MATERIAL AND METHODS: The 20E-EF was obtained by partitioning the methanol extract from P. glomerata roots with dichloromethane. Mice were treated by gavage with three doses of 20E-EF (3, 10, and 30 mg/kg) and parameters of stress, anxiety, and depression were evaluated. Biomarkers of oxidative stress (enzymes, antioxidant profile, and oxidized molecules) were evaluated in the cortex, striatum (basal ganglia), and hippocampus of animals treated with 30 mg/kg of 20E-EF. RESULTS: Mass spectrometry revealed that 20E was the main compound in the dichloromethane fraction. At a dose of 30 mg/kg, 20E-EF reduced stress, anxiety, and depression, while stimulating antioxidant enzymes (catalase, superoxide dismutase, and glutathione peroxidase), promoting antioxidant activity (antioxidant capacity, sulfhydryl groups, and reduced glutathione), and reducing oxidative markers (lipid peroxidation). In addition, 20E increased the concentration of NO in the striatum, possibly improving memory function and antioxidant activity. CONCLUSION: A 30 mg/kg dose of 20E-EF was able to reduce stress, anxiety, and depression, in addition to maintaining antioxidant defenses of the cortex and striatum. These findings open new perspectives for understanding the therapeutic properties of P. glomerata and the underlying mechanism(s).