This study was aimed to assess effects of three strains of probiotics Lactobacillus acidophilus NCFM, Lactobacillus rhamnosus HN001, and Bifidobacterium animalis subsp. lactis Bi-07 on the intestinal motility and inflammation in the zebrafish models. The intestinal motility model was established using 5 days postfertilization (dpf) zebrafish administered with a fluorescent dye Nile red at 10 ng/mL for 16 h, followed by probiotics treatment for 24 h and the intestinal motility was inversely proportional to the intestinal fluorescence intensity that was quantitatively measured by image analysis. The intestinal inflammation was induced by treating 3 dpf neutrophil fluorescent zebrafish with 0.0125% of trinitrobenzenesulfonic acid for 48 h. Probiotics were administered at low, moderate, and high concentrations determined based on maximum tolerable concentration through soaking. All three strains of probiotics promoted intestinal movement, of which B. animalis subsp. lactis Bi-07 was most potent at lower concentrations. L. rhamnosus HN001 and B. animalis subsp. lactis Bi-07 had the therapeutic effects on the intestinal inflammation and the inflammation-associated mucosal damage recovery. The anti-inflammatory mechanisms of L. rhamnosus HN001 was related to both reduce inflammatory factor interleukin-6 (IL-6) and restored tissue repair factor transforming growth factor-β-1 (TGFβ-1); whereas B. animalis subsp. lactis Bi-07 was probably only associated with TGFβ-1 elevation. Using larval zebrafish models for probiotics screening and assessment would speed up product research and development and improve products' efficacy and quality.
Keywords: intestinal inflammation; intestinal motility; probiotics; zebrafish.