The Effects of Synbiotics Administration on Stress-Related Parameters in Thai Subjects—A Preliminary Study

Urbanization influences our lifestyle, especially in fast-paced environments where we are more prone to stress. Stress management is considered advantageous in terms of longevity. The use of probiotics for psychological treatment has a small amount of diverse proven evidence to support this. However, studies on stress management in stressed subjects using synbiotics are still limited. The present study aimed to investigate the effects of synbiotics on stress in the Thai population. A total of 32 volunteers were enrolled and screened using a Thai Stress Test (TST) to determine their stress status. Participants were divided into the stressed and the non-stressed groups. Synbiotics preparation comprised a mixture of probiotics strains in a total concentration of 1 × 10(10) CFU/day (5.0 × 10(9) CFU of Lactobacillus paracasei HII01 and 5.0 × 10(9) CFU of Bifidobacterium animalis subsp. lactis) and 10 g prebiotics (5 g galacto-oligosaccharides (GOS), and 5 g oligofructose (FOS)). All parameters were measured at baseline and after the 12th week of the study. In the stressed group, the administration of synbiotics significantly (p < 0.05) reduced the negative scale scores of TST, and tryptophan. In the non-stressed group, the synbiotics administration decreased tryptophan significantly (p < 0.05), whereas dehydroepiandrosterone sulfate (DHEA-S), tumor necrosis factor-α (TNF-α), 5-hydroxyindoleacetic acid (5-HIAA), and short-chain fatty acids (SCFAs), acetate and propionate were increased significantly (p < 0.05). In both groups, cortisol, and lipopolysaccharide (LPS) were reduced, whereas anti-inflammatory mediator interleukin-10 (IL-10) and immunoglobulin A (IgA) levels were increased. In conclusion, synbiotics administration attenuated the negative feelings via the negative scale scores of TST in stressed participants by modulating the HPA-axis, IL-10, IgA, and LPS. In comparison, synbiotics administration for participants without stress did not benefit stress status but showed remodeling SCFAs components, HPA-axis, and tryptophan catabolism.