Immune stress in late pregnant rats decreases length of gestation and fecundity, and alters later cognitive and affective behaviour of surviving pre-adolescent offspring

Immune challenge during pregnancy is associated with preterm birth and poor perinatal development. The mechanisms of these effects are not known. 5α-Pregnan-3α-ol-20-one (3α,5α-THP), the neuroactive metabolite of progesterone, is critical for neurodevelopment and stress responses, and can influence cognition and affective behaviours. To develop an immune challenge model of preterm birth, pregnant Long–Evans rat dams were administered lipopolysaccharide [LPS; 30 μg/kg/ml, intraperitoneal (IP)], interleukin-1β (IL-1β; 1 μg/rat, IP) or vehicle (0.9% saline, IP) daily on gestational days 17–21. Compared to control treatment, prenatal LPS or IL-1β reduced gestational length and the number of viable pups born. At 28–30 days of age, male and female offspring of mothers exposed to prenatal IL-1β had reduced cognitive performance in the object recognition task compared to controls. In females, but not males, prenatal IL-1β reduced anxiety-like behaviour, indicated by entries to the centre of an open field. In the hippocampus, progesterone turnover to its 5α-reduced metabolites was lower in prenatally exposed IL-1β female, but not in male offspring. IL-1β-exposed males and females had reduced oestradiol content in hippocampus, medial prefrontal cortex and diencephalon compared to controls. Thus, immune stress during late pregnancy reduced gestational length and negatively impacted birth outcomes, hippocampal function and central neurosteroid formation in the offspring

Protein/Emulsifier Interactions

An important consequence of protein-lipid interaction is the effect on stability of the protein in solution as well as on its behavior at interfaces. Here we will discuss key aspects of protein aggregation and unfolding as well as the effects of protein structure (random coil proteins versus globular) that are relevant for our understanding protein-lipid interaction. The main types of emulsifiers are the (1) aqueous soluble, surfactant type and (2) lipids with low aqueous solubility. The monomer concentration as defined by cmc is an important parameter for the soluble lipids. For emulsifiers with low aqueous solubility the emulsifier self-assembly structure and its properties control the interaction with proteins. We will therefore summarize the main features of lipid self-assembly. It also allows us to define different plausible scenarios and principles and models for factors that control the interactions in real food (and Pharmaceutical) systems. For the food applications the fate of the lipid during digestion is important and therefore we will discuss some aspects of enzyme-catalyzed lipolysis in terms of the structural evolution. New products and concepts of using protein/emulsifier interactions will be exemplified by illustrating how food nanotechnology possibly can be used for the delivery of functionality