Krill oil reduces intestinal inflammation by improving epithelial integrity and impairing adherent-invasive Escherichia coli pathogenicity.
BACKGROUND
Krill oil is a marine derived oil rich in phospholipids, astaxanthin and omega-3 fatty acids. Several studies have found benefits of krill oil against oxidative and inflammatory damage.


OBJECTIVE
We aimed at assessing the ability of krill oil to reduce intestinal inflammation by improving epithelial barrier integrity, increasing cell survival and reducing pathogenicity of adherent-invasive Escherichia coli.


METHODS
CACO2 and HT29 cells were exposed to cytomix (TNFα and IFNγ) to induce inflammation and co-exposed to cytomix and krill oil. E-cadherin, ZO-1 and F-actin levels were analyzed by immunofluorescence to assess barrier integrity. Scratch test was performed to measure wound healing. Cell survival was analyzed by flow cytometry. Adherent-invasive Escherichia coli LF82 was used for adhesion/invasion assay.


RESULTS
In inflamed cells E-cadherin and ZO-1 decreased, with loss of cell-cell adhesion, and F-actin polymerization increased stress fibres; krill oil restored initial conditions and improved wound healing, reduced bacterial adhesion/invasion in epithelial cells and survival within macrophages; krill oil reduced LF82-induced mRNA expression of pro-inflammatory cytokines.


CONCLUSIONS
Krill oil improves intestinal barrier integrity and epithelial restitution during inflammation and controls bacterial adhesion and invasion to epithelial cells. Thus, krill oil may represent an innovative tool to reduce intestinal inflammation.
Department of Radiobiology and Human Health, ENEA, Rome, Italy.
Manuela
M
Costanzo
Department of Radiobiology and Human Health, ENEA, Rome, Italy.
Vincenzo
V
Cesi
Department of Radiobiology and Human Health, ENEA, Rome, Italy.
Enrica
E
Prete
Department of Radiobiology and Human Health, ENEA, Rome, Italy.
Anna
A
Negroni
Department of Radiobiology and Human Health, ENEA, Rome, Italy.
Francesca
F
Palone
Department of Paediatrics and Infantile Neuropsychiatry, Paediatric Gastroenterology and Liver Unit, Sapienza University of Rome, Italy.
Salvatore
S
Cucchiara
Department of Paediatrics and Infantile Neuropsychiatry, Paediatric Gastroenterology and Liver Unit, Sapienza University of Rome, Italy.
Salvatore
S
Oliva
Department of Paediatrics and Infantile Neuropsychiatry, Paediatric Gastroenterology and Liver Unit, Sapienza University of Rome, Italy.
Beatrice
B
Leter
Department of Radiobiology and Human Health, ENEA, Rome, Italy. Electronic address: laura.stronati@enea.it.
Laura
L
Stronati
D000199:Actins / Q000378:metabolism; D000818:Animals; D001422:Bacterial Adhesion / Q000187:drug effects*; D018938:Caco-2 Cells; D015820:Cadherins / Q000378:metabolism; D002448:Cell Adhesion / Q000187:drug effects; D016923:Cell Death / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects*; D004926:Escherichia coli / Q000472:pathogenicity / Q000502:physiology; D004927:Escherichia coli Infections / Q000276:immunology; D033201:Euphausiacea; D015525:Fatty Acids, Omega-3 / Q000494:pharmacology*; D019073:HT29 Cells; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology; D016209:Interleukin-8 / Q000235:genetics / Q000378:metabolism; D051379:Mice; D050296:Microbial Viability / Q000187:drug effects*; D000067996:RAW 264.7 Cells; D012333:RNA, Messenger / Q000187:drug effects*; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D014945:Wound Healing / Q000187:drug effects; D062826:Zonula Occludens-1 Protein / Q000378:metabolism
D000199:Actins; D015820:Cadherins; D015525:Fatty Acids, Omega-3; D016209:Interleukin-8; D012333:RNA, Messenger; C569042:TJP1 protein, human; D014409:Tumor Necrosis Factor-alpha; D062826:Zonula Occludens-1 Protein; D007371:Interferon-gamma
Antarctic krill; Intestinal epithelium; Luminal bacteria