Bovine milk fat enriched in conjugated linoleic and vaccenic acids attenuates allergic airway disease in mice.
BACKGROUND
It has been argued that a reduction in the Western diet of anti-inflammatory unsaturated lipids, such as n-3 polyunsaturated fatty acids, has contributed to the increase in the frequency and severity of allergic diseases.


OBJECTIVE
We investigated whether feeding milk fat enriched in conjugated linoleic acid and vaccenic acids (VAs) ('enriched' milk fat), produced by supplementing the diet of pasture-fed cows with fish and sunflower oil, will prevent development of allergic airway responses.


METHODS
C57BL/6 mice were fed a control diet containing soybean oil and diets supplemented with milk lipids. They were sensitized by intraperitoneal injection of ovalbumin (OVA) on days 14 and 28, and challenged intranasally with OVA on day 42. Bronchoalveolar lavage fluid, lung tissues and serum samples were collected 6 days after the intranasal challenge.


RESULTS
Feeding of enriched milk fat led to marked suppression of airway inflammation as evidenced by reductions in eosinophilia and lymphocytosis in the airways, compared with feeding of normal milk fat and control diet. Enriched milk fat significantly reduced circulating allergen-specific IgE and IgG1 levels, together with reductions in bronchoalveolar lavage fluid of IL-5 and CCL11. Treatment significantly inhibited changes in the airway including airway epithelial cell hypertrophy, goblet cell metaplasia and mucus hypersecretion. The two major components of enriched milk fat, cis-9, trans-11 conjugated linoleic acid and VA, inhibited airway inflammation when fed together to mice, whereas alone they were not effective.


CONCLUSIONS
Milk fat enriched in conjugated linoleic and VAs suppresses inflammation and changes to the airways in an animal model of allergic airway disease.
Kanwar
R K
RK
LactoPharma Consortium, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand.
Macgibbon
A K
AK
Black
P N
PN
Kanwar
J R
JR
Rowan
A
A
Vale
M
M
Krissansen
G W
GW
D000485:Allergens / Q000276:immunology; D000818:Animals; D002470:Cell Survival; D054413:Chemokine CCL11 / Q000096:biosynthesis; D004804:Eosinophils / Q000166:cytology / Q000276:immunology; D005223:Fats / Q000276:immunology*; D005260:Female; D006967:Hypersensitivity / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D007136:Immunoglobulins / Q000096:biosynthesis / Q000276:immunology; D015848:Interleukin-5 / Q000096:biosynthesis; D019787:Linoleic Acid / Q000276:immunology*; D008173:Lung Diseases, Obstructive / Q000276:immunology* / Q000378:metabolism / Q000473:pathology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008892:Milk / Q000276:immunology*; D009829:Oleic Acids / Q000276:immunology*
D000485:Allergens; D054413:Chemokine CCL11; D005223:Fats; D007136:Immunoglobulins; D015848:Interleukin-5; D009829:Oleic Acids; D019787:Linoleic Acid; C050413:11-octadecenoic acid