Lactobacillus plantarum and Bifidobacterium bifidum alleviate dry eye. - GreenMedInfo Summary
Lactobacillus plantarum and Bifidobacterium bifidum alleviate dry eye in mice with exorbital lacrimal gland excision by modulating gut inflammation and microbiota.
Food Funct. 2021 Mar 21 ;12(6):2489-2497. Epub 2021 Mar 3. PMID: 33656499
In order to understand the efficacy of probiotics against dry eye syndrome, we selected anti-inflammatory probiotics Lactobacillus plantarum NK151 and Bifidobacterium bifidum NK175, which increased the ratio of IL-10 to TNF-α expression, from the human gut bacteria collection and examined their effects on tear secretion and cornea/conjunctiva inflammation in mice with excision of the unilateral exorbital lacrimal gland and 1% atropine and 0.1% benzalkonium chloride solution (ELA)-induced dry eye. Exposure to ELA significantly reduced tear secretion in mice, assessed by the phenol red thread tear test. However, oral gavage of NK151 and/or NK175 significantly increased ELA-suppressed tear secretion, IL-10 expression, and goblet cell population and decreased the ELA-induced corneal fluorescein-staining score, IL-1βand TNF-α expression in the conjunctiva. They also suppressed ELA-induced myeloperoxidase, IL-1β, and TNF-α expression. In particular, they increased the ratio of IL-10 to TNF-α expression in the colon. Their treatments increased ELA-induced α-diversity reduction to that of the control group and partially restored ELA-shifted β-diversity to that of the control group. Oral gavage of NK151 and/or NK175 reduced ELA-induced Verrucomicrobia and Actinobacteria populations at the phylum level. Furthermore, they reduced ELA-induced Bacteroidaceae, Akkemansiaceae, and AC160630_f populations andincreased ELA-suppressed Lactobacillaceae and Muribaculaceae populations at the family level. These gut bacteria populations exhibited significant correlation with the tear secretion volume. In conclusion, NK151 and/or NK175 alleviated dry eye by modulating the expression ratio of pro-inflammatory cytokines such as TNF-α and anti-inflammatory cytokines such as IL-10 and gut microbiota composition.