Höfundar:
Kirstine Nolling Jensen, Marieke Heijink, Martin Giera, Jona Freysdottir, Ingibjorg Hardardottir
Introduction: Acute inflammation is characterized by influx of inflammatory cells and production of pro-inflammatory mediators. If improperly resolved it progresses into chronic inflammation, which contributes to approximately half of disease-associated deaths worldwide. Resolution of inflammation is promoted by specialized pro-resolving lipid mediators synthesized from omega-3 and omega-6 polyunsaturated fatty acids (PUFAs). The aim of this study was to determine the effects of dietary fish oil, rich in omega-3 PUFAs, on hallmarks of resolution of inflammation in antigen-induced peritonitis.
Methods: Mice were fed fish oil-enriched or control diets, immunized twice and challenged intraperitoneally with methylated bovine serum albumin. Surface molecule expression on peritoneal cells was determined by flow cytometry; concentration of soluble mediators by ELISA and Luminex; lipid mediators by LC-MS/MS; and number of apoptotic cells in lymph nodes by TUNEL staining.
Results: Dietary fish oil shortened the resolution interval (the time it takes to decrease the number of neutrophils from peak to half); decreased peritoneal neutrophil numbers, increased their apoptosis levels, and decreased neutrophil expression of an ‘eat-me-not’ molecule in inflamed mice. Concentrations of pro-inflammatory mediators were lower in inflamed mice fed the fish oil diet compared to that in mice fed the control diet while growth factor and decoy receptor levels were higher. Finally, dietary fish oil dampened peritoneal concentrations of prostanoids while increasing pro-resolving lipid mediator concentrations in inflamed mice.
Conclusions: Our data indicate that dietary fish oil can alleviate inflammatory flare-ups by enhancing resolution of inflammation. Thus, dietary fish oil could be beneficial in inflammation-related degenerative diseases.