Purpose: The objective of this study was to determine the effect of feeding a maternal diet supplemented with docosahexaenoic acid (DHA) while also containing adequate amounts of arachidonic acid on immune system development and function in suckled offspring and lactating rats.
Methods: Sprague-Dawley dams were randomized to one of the two nutritionally adequate experimental diets 24-48 h prior to parturition: control diet (N = 12, 0 % DHA) or high DHA diet (N = 8, 0.9 % DHA of total fatty acids). Diets were fed throughout the lactating/suckling period (21 days), and then, dams and pups were terminated, and immune cell phenotypes and cytokine production by mitogen- or ovalbumin-stimulated splenocytes were measured.
Results: Feeding dams a high DHA diet resulted in a higher proportion of 18:3n-3, 22:5n-3 and 22:6n-3 found in pup's stomach content (breast milk; P < 0.01). Feeding the high DHA diet had no impact on growth parameters or the ex vivo cytokine production by mitogen-stimulated splenocytes in both dams and pups. There was a higher proportion of OX12+CD80+ cells and a lower production of TGF-β by splenocytes after ovalbumin stimulation in pups from dams fed the DHA diet (both P < 0.05) while maintaining a similar IL-2 production. LPS-stimulated splenocytes from dams fed the high DHA diet produced more TNF-α versus control diet (P < 0.05).
Conclusions: Overall, our results suggest that DHA supplementation in the maternal diet does not change the immune response to mitogens but positively affects the activation of B cells as well as the response to a potential food antigen upon challenge in suckled offspring.
Keywords: Development; Immune system; Lactation; Offspring; Spleen.