Immunomodulatory activity and protective effects of chokeberry fruit extract on Listeria monocytogenes infection in mice

• Published in: Food & function Vol. 11; no. 9; pp. 7793 - 7803
• Main Authors: Gajić, Dragica, Saksida, Tamara, Koprivica, Ivan, Šenerović, Lidija, Morić, Ivana, Šavikin, Katarina, Menković, Nebojša, Pejnović, Nada, Stojanović, Ivana
• Format: Journal Article
• Language: English
• Published: England Royal Society of Chemistry 23.09.2020
• Subjects: Animal tissues; Animals; Antiinfectives and antibacterials; Antiviral agents; Bacteria; Bacterial diseases; Bacterial infections; Body weight; CD11b antigen; CD11c antigen; CD8 antigen; CD86 antigen; Cell differentiation; Cytotoxicity; Dendritic cells; Dendritic Cells - immunology; Dendritic Cells - metabolism; Differentiation (biology); Fruit - chemistry; Fruits; Gut-associated lymphoid tissues; Immunologic Factors - pharmacology; Immunomodulation; Infections; Interleukin 6; Intestine, Small - immunology; Listeria; Listeria monocytogenes; Listeria monocytogenes - isolation & purification; Listeriosis - drug therapy; Listeriosis - immunology; Listeriosis - microbiology; Lymphocytes; Lymphocytes T; Lymphoid tissue; Lymphoid Tissue - immunology; Macrophages; Macrophages - immunology; Macrophages - metabolism; Male; Mice; Mice, Inbred BALB C; Myeloid cells; Nitric oxide; Nitric Oxide Synthase Type II - metabolism; Nitric-oxide synthase; Notch1 protein; Perforin; Peritoneum; Phagocytosis; Phosphorylation; Photinia - chemistry; Phytotherapy; Plant Extracts - pharmacology; Polyphenols; Pretreatment; Reactive oxygen species; Reactive Oxygen Species - metabolism; Rodents; Spleen; Spleen - immunology; Spleen - microbiology; T-Lymphocytes, Cytotoxic - immunology; T-Lymphocytes, Cytotoxic - metabolism
• ISSN: 2042-6496; 2042-650X
• DOI: 10.1039/d0fo00946f

Chokeberry (Aronia melanocarpa) fruit extracts (CE) are rich in polyphenols and usually exhibit immunomodulatory, anti-viral and anti-bacterial effects. We have previously shown that the CE used in this study activated macrophages and stimulated effector T cell differentiation in vitro. When applied orally to healthy mice, CE increased the proportion of CD11c+ dendritic cells in the gut-associated lymphoid tissue. CE-pretreated BALB/c mice readily eradicated orally ingested Listeria monocytogenes as evidenced by a slighter decrease in body weight and number of bacteria recovered from the spleen and reduced spleen size compared to the control infected mice. CE pretreatment in infected mice resulted in higher proportions of CD11b+ macrophages and CD8+ cytotoxic T cells both in the gut and the spleen. Phagocytosis, reactive oxygen species production and the proportions of activated CD86+ macrophages (CD11b+) and dendritic cells (CD11c+) were also enhanced in CE-pretreated infected mice. Furthermore, the expression of inducible nitric oxide synthase and IL-6 was increased in CE-pretreated infected mice and similar results were obtained in peritoneal macrophages in vitro. This effect of CE was associated with increased phosphorylation of IκB and Notch1 production. Finally, CE pretreatment elevated the proportion of perforin-producing cells in the spleen compared to control infected mice. This study demonstrates that prophylactic treatment with CE leads to more rapid eradication of bacterial infection with L. monocytogenes predominantly through increased activity of myeloid cells in the gut and in the spleen.