Choline intake in pregnancy and lactation modifies liver transcriptome profile in the offspring of female rats with nonalcoholic fatty liver disease

The aim of the study was to analyze the impact of choline intake during pregnancy and/or lactation on histological alternation and gene expression profile in the liver of NAFLD dam progeny. We hypothesized that offspring of mothers suffering from non-alcoholic fatty liver (NAFLD) is more prone to develop fatty liver, because of suboptimal intrauterine environment. The performed analyses included histological examination of liver tissue obtained from 24-day-old male rats, which were offspring of dams with fatty liver: provided with proper choline amount during pregnancy and lactation (NN), fed a choline-deficient diet during these both periods (DD), deprived with choline only during pregnancy (DN) or only during lactation (ND). The global gene expression profile was analyzed by using microarray approach (Affymetrix® Rat Gene 2.1 ST Array Strip). Thirty-four animals were included in the study: seventeen dams and seventeen male offspring. Eighteen female and nine male rats eight weeks old were obtained from Charles River Laboratories (Germany). Animals were housed at the Laboratory of the Department of Human Nutrition and Dietetics, Poznań University of Life Sciences under standard conditions (12/12 h light/dark cycle, 21 ± 1 °C, humidity 55 %–65 %,) and were kept in pairs/in threes within the same sex in stainless steel cages coated with metal-free enamel. After a five-day adaptation period, when animals have been fed standard maintenance diet Labofeed B (Morawski, Poland), females started to be fed with the AIN-93 M diet deficient in choline (D group, n=17, one dam was excluded from the study because of malocclusion) for 16 weeks to establish a fatty liver model. Next, dams were mated with healthy Wistar males fed with the standard AIN-93 M diet. A vaginal plug was the evidence of mating. Pregnant dams with fatty liver were randomized to two subgroups: one was still fed the diet deficient in choline (D group, n=9); the second one started to receive proper choline amounts in the diet (standard AIN-93 G diet; N group, n=8). Three days before expected delivery, dams started to be kept in a single cage. After delivery, the animals from the D group were randomized once again into two subgroups, which were still fed the diets deficient in choline (DD group, n=4) or with the standard AIN-93 G diet (DN group, n=5). The same was done with animals from the N group – one subgroup was still fed standard AIN-93 G diet (NN group, n=4) and the second started to be fed diet deficient in choline (ND group, n=4). This feeding method in the DD, DN, ND and NN groups were continued till 24. day after delivery, when one male from each litter was sacrificed for tissue collection.