The effects of butyrate enemas on visceral perception in healthy volunteers.
Level 2 - randomized trial
Randomized, double-blind, placebo-controlled crossover trial
PubMed 19460106 · doi:10.1111/j.1365-2982.2009.01324.x
What was done
Eleven healthy volunteers participated in a randomized, double-blind, placebo-controlled crossover trial consisting of three 1-week periods. Participants self-administered daily rectal enemas before sleep containing 50 mmol/L butyrate, 100 mmol/L butyrate, or saline placebo. Visceral perception (pain, urge, and discomfort) was assessed at the start and end of each test period using rectal barostat distension testing.
What was found
Butyrate produced a dose-dependent reduction in visceral pain, urge, and discomfort across the tested pressure range. At 4 mmHg distension pressure, 50 and 100 mmol/L butyrate reduced pain scores by 23.9% and 42.1%, and discomfort scores by 44.2% and 69.0%, respectively. At 67 mmHg, 50 and 100 mmol/L butyrate decreased pain scores by 23.8% and 42%, and discomfort scores by 1.9% and 5.2%, respectively.
Why it matters
Contrary to rodent findings showing butyrate-induced visceral hypersensitivity, physiological concentrations of colonic butyrate reduced visceral pain and discomfort in humans. This suggests short-chain fatty acids may modulate visceral perception favorably in human colonic mucosa.
Limits
The study has a very small sample size (n = 11) and was conducted exclusively in healthy volunteers, limiting applicability to conditions like irritable bowel syndrome. Each treatment lasted only 1 week, and the abstract does not report p-values, confidence intervals, or washout period details.
Cited by
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