An exploratory investigation of endotoxin levels in novice long distance triathletes, and the effects of a multi-strain probiotic/prebiotic, antioxidant intervention.

Abstract: Gastrointestinal (GI) ischemia during exercise is associated with luminal permeability and increased systemic lipopolysaccharides (LPS). This study aimed to assess the impact of a multistrain pro/prebiotic/ antioxidant intervention on endotoxin unit levels and GI permeability in recreational athletes. Thirty healthy participants (25 males, 5 females) were randomly assigned either a multistrain pro/prebiotic/ antioxidant (LAB4ANTI; 30 billion CFU.d-1 containing 10 billion CFU.d-1 Lactobacillus acidophilus CUL-60 [NCIMB 30157], 10 billion CFU.d-1 Lactobacillus acidophillus CUL-21 [NCIMB 30156], 9.5 billion CFU.d-1 Bifidobacterium bifidum CUL-20 [NCIMB 30172] and 0.5 billion CFU.d-1 Bifidobacterium animalis subspecies lactis CUL-34 [NCIMB 30153]/ 55.8 mg.d-1 fructooligosaccharides/ 400 mg.d-1 α-lipoic acid, 600 mg.d-1 N-acetyl-carnitine); matched pro/prebiotic (LAB4) or placebo (PL) for 12 weeks preceding a long-distance triathlon. Plasma endotoxin units (via Limulus amebocyte lysate chromogenic quantification) and GI permeability (via 5 hour urinary lactulose (L): mannitol (M) recovery) were assessed at baseline, pre-race and 6 days post-race. Endotoxin unit levels were not significantly different between groups at baseline (LAB4ANTI: 8.20±1.60 pg.ml-1; LAB4: 8.92±1.20 pg.ml-1; PL: 9.72± 2.42 pg.ml-1). The use of a 12 week LAB4ANTI intervention significantly reduced endotoxin units both pre-race (4.37± 0.51 pg.ml-1) and 6 days post-race (5.18±0.57 pg.ml-1; p=0.03, ηp2 = 0.35), but only 6 days post-race with LAB4 (5.01± 0.28 pg.ml-1; p=0.01, ηp2 = 0.43). In contrast, endotoxin units remained unchanged with PL. L:M significantly increased from 0.01±0.01 at baseline to 0.06± 0.01 with PL only (p=0.004, ηp2 = 0.51). Mean race times (hr:min:sec) were not statistically different between groups despite faster times with both pro/prebiotoic groups (LAB4ANTI:13:17:07±34:48; LAB4: 12:47:13±25:06; PL: 14:12:51±29:54; p>0.05). Combined multistrain pro/prebiotic use may reduce endotoxin unit levels, with LAB4ANTI potentially conferring an additive effect via combined GI modulation and antioxidant protection.