Effect of docosahexenoic acid microalgae oil supplementation during pregnancy and lactation on levels of serum polyunsaturated fatty acid and tolerance to ovalbumin in suckling mice

Abstract

Objective: To study the tolerance to ovalbumin (OVA) in suckling mice whose mothers had different doses of docosahexenoic acid (DHA) microalgae oil (DMO) supplementation during pregnancy and lactation. Method: According to different doses of DMO fed to mother mice during pregnancy and lactation, 66 suckling mice were divided into four groups. Suckling mice whose mothers were fed with 0.7% DMO were designated as low dose group (group L) (n=16), 2.1% DMO as middle dose group (group M) (n=16), 3.5% DMO as high dose group (group H) (n=17) and no DMO as control group (n=17). Before exposing to OVA, 8 suckling mice were killed in each group at 21-day-old. Remaining suckling mice were killed at 59-day-old after repeated OVA exposure. The serum polyunsaturated fatty acid (PUFA) levels of suckling mice were analyzed by high performance liquid chromatography (HPLC) at the age of 21- and 59-day.Histological examinations of jejunum were performed by HE staining and the mast cells in jejunum were observed by toluidine blue staining. OVA-IgE in serum, total IgA and OVA-IgA in the feces and IL-4 and IFN-γ in the supernatants of splenic mononuclear cells (SMC) were measured by ELISA. Real time PCR was performed to identify the gene expression of IL-10, TGF-β1 mRNA in SMC. Differences among groups were compared by one-way AVOVA and that between each group were compared by LSD. Result: In group M and H, the serum levels of n-3DHA (108±29)μg/ml; (102±34)μg/ml vs.(40±19)μg/ml (F=12.052, P=0.000)and n-3 eicosapentaenoic acid (6.7±2.3)μg/ml; (7.7±2.0)μg/ml vs. (3.9±1.1)μg/ml(F=9.573, P=0.000) were significantly higher than that in control group at the age of 21-day. The serum levels of n-3DHA were higher in group H (17.1±2.9)μg/ml than that in control group (5.9±3.3) μg/ml after repeated OVA exposure at the age of 59-day (F=10.339, P<0.000). Compared with control group (53±12) pg/ml, the levels of IL-4 in SMC in group H (42±9)pg/ml were lower (F=2.484, P<0.05). Conclusion: The serum levels of DHA in baby mice, whose mothers was fed with DMO during pregnancy and lactation, were significantly increased till adulthood. However, the effect on tolerance to OVA was limited.