Lactobacillus plantarum PS128 reversed visceral hypersensitivity in IBS-like rats by normalizing substance P, CGRP, BDNF, and NGF levels across the gut-brain axis.
14 days reversed VHTwo weeks of daily PS128 probiotic completely reversed serotonin-induced visceral hypersensitivity
What the researchers found
PS128 reversed 5-HTP-induced visceral hypersensitivity and normalized substance P, CGRP, BDNF, and NGF distribution between dorsal root ganglia and spinal cord.
Why it matters
IBS affects 10-15% of people globally with limited treatment options. A probiotic that modulates the gut-brain axis through neuropeptide pathways offers a mechanistically grounded approach.
The numbers in context
10^9 CFU/day x 14 days; reversed SP, CGRP, BDNF, NGF changes; lowered corticosterone
How the study worked
Rat IBS model (5-HTP-induced visceral hypersensitivity without inflammation); 14 days oral PS128 (10⁹ CFU/day); colorectal distension with EMG; neuropeptide and neurotrophin levels in DRG, spinal cord; serum corticosterone; amygdala receptor expression.
Who was studied
Male Sprague-Dawley rats with 5-HTP-induced visceral hypersensitivity (IBS model)
What this study cannot tell us
Rat model — IBS in humans is more complex; 5-HTP model mimics only one aspect of IBS; 14 days may not reflect long-term effects; single probiotic strain tested.
How to read the evidence
Moderate — well-designed animal study with comprehensive neuropeptide analysis, but rat IBS model may not fully represent human disease.
When this study was published
Published in 2020; PS128 has been studied in clinical trials for other conditions since.
The bigger picture
The gut-brain axis is central to IBS pathology. This study provides molecular evidence for how a specific probiotic strain modulates pain neuropeptides, moving beyond "probiotics are good for gut health" to mechanistic understanding.
Questions still open
- Would PS128 reduce visceral pain in human IBS clinical trials?
- Is the neuropeptide normalization a direct effect of PS128 or mediated through gut microbiome changes?
- Could PS128 be combined with other IBS treatments for enhanced benefit?
Common questions
How can a probiotic reduce pain?
Would this probiotic help my IBS?
Read the original research
Lactobacillus plantarum PS128 Ameliorated Visceral Hypersensitivity in Rats Through the Gut-Brain Axis.
Probiotics and antimicrobial proteins, 12(3), 980-993
Citation
Liu, Yen-Wenn; Wang, Yen-Po; Yen, Hsu-Fang; Liu, Pei-Yi; Tzeng, Wen-Jian; Tsai, Chia-Fen; Lin, Han-Chieh; Lee, Fa-Yauh; Jeng, One-Jang; Lu, Ching-Liang; Tsai, Ying-Chieh. (2020). Lactobacillus plantarum PS128 Ameliorated Visceral Hypersensitivity in Rats Through the Gut-Brain Axis.. Probiotics and antimicrobial proteins, 12(3), 980-993. https://doi.org/10.1007/s12602-019-09595-w