Immunomodulatory Effect of Bifidobacterium, Lactobacillus, and Streptococcus Strains of Paraprobiotics in Lipopolysaccharide-Stimulated Inflammatory Responses in RAW-264.7 Macrophages.
Journal
Current microbiology
ISSN: 1432-0991
Titre abrégé: Curr Microbiol
Pays: United States
ID NLM: 7808448
Informations de publication
Date de publication:
14 Dec 2021
14 Dec 2021
Historique:
received:
04
03
2021
accepted:
11
10
2021
entrez:
14
12
2021
pubmed:
15
12
2021
medline:
17
12
2021
Statut:
epublish
Résumé
The discovery of the potential of paraprobiotics to exert different immunological benefits suggests that further studies should be carried out to determine their potential and mechanisms of action in modulating the immune system. The objective of this study was to investigate the immune response of several microbial-associated molecular patterns (MAMPS) used at different doses in macrophage cell lines RAW-264.7 stimulated with lipopolysaccharide (LPS). Two experiments were conducted. The first was performed to determine a dose response curve for each paraprobiotic (Bifidobacterium lactis, Lactobacillus casei, Lactobacillus gasseri, Lactobacillus paracasei, and Streptococcus thermophilus). Further experiments were carried using only two doses (0.01 g/ml and 0.1 g/ml). RAW-264.7 cells were cultivated in Dubelcco's Modified Eagle's medium supplemented with fetal bovine serum and penicillin/streptomycin. Cells were incubated with LPS (1 μg/ml) and six concentrations of MAMPs were added. RAW-264.7 viability, myeloperoxidase activity, nitrite/nitrate concentration, reactive oxygen species production, oxidative damage, and inflammatory parameters were measured. In the LPS group, there was a significant reduction in cell viability. Myeloperoxidase and nitrite/nitrate concentrations demonstrated a better effect at 0.01 and 0.1 g/ml doses. There was a significant reduction in interleukin-6 (IL-6) levels at 0.1 g/ml dose in all paraprobiotics. IL-10 levels decreased in the LPS group and increased at 0.1 g/ml dose in all paraprobiotics. The dichlorofluorescin diacetate results were reinforced by the observed in oxidative damage. Paraprobiotics are likely to contribute to the improvement of intestinal homeostasis, immunomodulation, and host metabolism.
Identifiants
pubmed: 34905100
doi: 10.1007/s00284-021-02708-1
pii: 10.1007/s00284-021-02708-1
doi:
Substances chimiques
Lipopolysaccharides
0
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
9Informations de copyright
© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
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