Supplementation with extract of Gynostemma pentaphyllum leaves reduces anxiety in healthy subjects with chronic psychological stress: A randomized, double-blind, placebo-controlled clinical trial.

BACKGROUND

The ethanol extract of Gynostemma pentaphyllum Makino leaves (EGP) has been reported recently to have anxiolytic effects on chronically stressed mice models.

PURPOSE: We aimed to investigate the efficacy and safety of EGP on anxiety level in healthy Korean subjects under chronic stressful conditions.

STUDY

DESIGN

Double-blind, placebo-controlled trial.

METHODS

This study was conducted with 72 healthy adults who had perceived chronic stress and anxiety with a score on the State-Trait Anxiety Inventory (STAI) from 40 to 60. Participants were randomly assigned to receive either EGP (200 mg, twice a day, N = 36) or placebo (N = 36). All participants were exposed to repetitive loads of stress by performing the serial subtraction task for 5 min every second day during the 8-week intervention. Primary outcome of Trait-STAI and secondary outcomes of State-STAI, total score of STAI, Hamilton Anxiety Inventory (HAM-A), Beck Anxiety Inventory (BAI), blood norepinephrine and adrenocorticotropic hormone (ACTH), salivary cortisol and alpha-amylase, cardiovascular autonomic nervous system (ANS) functional test, and heart rate variability (HRV) test were measured before and after intervention.

RESULTS

After the 8-week intervention, the EGP significantly lowered the score of the Trait Anxiety Scale of the STAI (T-STAI) by 16.8% compared to the placebo (p = 0.041). The total score on the STAI decreased by 17.8% in the EGP group and tended to improve compared with that of the placebo group (p = 0.067). There were no significant differences in the changes in score of S-STAI, HAM-A, BAI, and other parameters from baseline between the two groups. There was no causal relationship between the ingestion of EGP and adverse drug reactions.

CONCLUSION

We found that supplementation with EGP reduced "anxiety proneness" in subjects under chronic psychological stress, as shown by a decrease in the score of T-STAI and the tendency for decrease in the total score of STAI. This result suggests that EGP supplementation can be used as a regimen to safely reduce stress and anxiety; however, more studies are needed to establish the long-term safety and effectiveness.