AUTHOR=Yang Yang , Zhao Yuanji , Lei Huan 

TITLE=Protective effects of Lactococcus lactis subsp. lactis HFY14 supplementation on the brain, intestines, and motor function of antibiotic-treated mice

JOURNAL=Frontiers in Microbiology

VOLUME=15

YEAR=2024

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2024.1418556

DOI=10.3389/fmicb.2024.1418556

ISSN=1664-302X

ABSTRACT=<sec><title>Introduction</title><p>This study aimed to explore the anti-oxidative and anti-inflammatory properties of <italic>Lactococcus lactis subsp</italic>. <italic>lactis</italic> HFY14 (LLSLHFY14) and investigate its effects on the intestinal barrier, cranial nerve, and motor function in mice treated with antibiotics.</p></sec><sec><title>Methods</title><p>Mice were administered an antibiotic mixture (neomycin 5 mg/mL, vancomycin 25 mg/mL, amphotericin B 0.1 mg/mL, ampicillin 10 mg/mL, metronidazole file 5 mg/mL, and lipopolysaccharide 1.5 μg/mL) intraperitoneally, and oxidative stress and inflammatory markers in the serum and brain tissues, and liver index were measured. H&amp;E staining was performed to detect pathological alterations in brain tissues. The expression of intestinal-barrier-related genes and that of genes involved in inflammatory pathways in the brain were detected using polymerase chain reaction (PCR).</p></sec><sec><title>Results</title><p>LLSLHFY14 administration extended the weight-loaded swimming and running times of mice and decreased the liver index. Moreover, the levels of malondialdehyde (MDA), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α) in the serum and brain tissue were reduced, whereas those of superoxide dismutase (SOD), glutathione (GSH), and interleukin-10 (IL-10) were elevated. Elevated brain expression of the protein kinase B (<italic>AKT</italic>)/cAMP-response element binding protein (<italic>CREB</italic>)/brain-derived neurotrophic factor (<italic>BDNF</italic>)/extracellular signal-regulated kinase 1 (<italic>ERK1</italic>) pathway, decreased brain expression of the <italic>IL-6</italic> gene, and elevated cecum expression of <italic>zonula occludens-1 (ZO-1), occludin-1</italic>, and <italic>claudin-1</italic> genes were noted. LLSLHFY14 supplementation significantly increased <italic>Bacteroidetes</italic> expression but decreased <italic>Firmicutes</italic> expression, thus increasing the <italic>Bacteroidetes/Firmicutes</italic> ratio.</p></sec><sec><title>Discussion</title><p>Overall, LLSLHFY14 supplementation ameliorated antibiotic-induced oxidative stress and inflammation in the mouse central nervous system, intestinal barrier dysfunction, and increased motor function, thus confirming its potential application as probiotics.</p></sec>