Alterations in lipid metabolism due to a protein-restricted diet in rats during gestation and/or lactation

Non-coding RNAs: The link between maternal malnutrition and offspring metabolism

Early life nutrition is associated with the development and metabolism in later life, which is known as the Developmental Origin of Health and Diseases (DOHaD). Epigenetics have been proposed as an important explanation for this link between early life malnutrition and long-term diseases. Non-coding RNAs (ncRNAs) may play a role in this epigenetic programming. The expression of ncRNAs (such as long non-coding RNA H19, microRNA-122, and circular RNA-SETD2) was significantly altered in specific tissues of offspring exposed to maternal malnutrition. Changes in these downstream targets of ncRNAs lead to abnormal development and metabolism. This review aims to summarize the existing knowledge on ncRNAs linking the maternal nutrition condition and offspring metabolic diseases, such as obesity, type 2 diabetes (T2D) and non-alcoholic fatty liver disease (NAFLD).

Cardiometabolic Effects of Postnatal High-Fat Diet Consumption in Offspring Exposed to Maternal Protein Restriction In Utero

In recent decades, the high incidence of infectious and parasitic diseases has been replaced by a high prevalence of chronic and degenerative diseases. Concomitantly, there have been profound changes in the behavior and eating habits of families around the world, characterizing a "nutritional transition" phenomenon, which refers to a shift in diet in response to modernization, urbanization, or economic development from undernutrition to the excessive consumption of hypercaloric and ultra-processed foods. Protein malnutrition that was a health problem in the first half of the 20th century has now been replaced by high-fat diets, especially diets high in saturated fat, predisposing consumers to overweight and obesity. This panorama points us to the alarming coexistence of both malnutrition and obesity in the same population. In this way, individuals whose mothers were undernourished early in pregnancy and then exposed to postnatal hyperlipidic nutrition have increased risk factors for developing metabolic dysfunction and cardiovascular diseases in adulthood. Thus, our major aim was to review the cardiometabolic effects resulting from postnatal hyperlipidic diets in protein-restricted subjects, as well as to examine the epigenetic repercussions occasioned by the nutritional transition.

Animal Foetal Models of Obesity and Diabetes - From Laboratory to Clinical Settings

The prenatal period, during which a fully formed newborn capable of surviving outside its mother's body is built from a single cell, is critical for human development. It is also the time when the foetus is particularly vulnerable to environmental factors, which may modulate the course of its development. Both epidemiological and animal studies have shown that foetal programming of physiological systems may alter the growth and function of organs and lead to pathology in adulthood. Nutrition is a particularly important environmental factor for the pregnant mother as it affects the condition of offspring. Numerous studies have shown that an unbalanced maternal metabolic status (under- or overnutrition) may cause long-lasting physiological and behavioural alterations, resulting in metabolic disorders, such as obesity and type 2 diabetes (T2DM). Various diets are used in laboratory settings in order to induce maternal obesity and metabolic disorders, and to alter the offspring development. The most popular models are: high-fat, high-sugar, high-fat-high-sugar, and cafeteria diets. Maternal undernutrition models are also used, which results in metabolic problems in offspring. Similarly to animal data, human studies have shown the influence of mothers' diets on the development of children. There is a strong link between the maternal diet and the birth weight, metabolic state, changes in the cardiovascular and central nervous system of the offspring. The mechanisms linking impaired foetal development and adult diseases remain under discussion. Epigenetic mechanisms are believed to play a major role in prenatal programming. Additionally, sexually dimorphic effects on offspring are observed. Therefore, further research on both sexes is necessary.

Paternal High-Protein Diet Programs Offspring Insulin Sensitivity in a Sex-Specific Manner

The impact of maternal nutrition on offspring is well documented. However, the implication of pre-conceptional paternal nutrition on the metabolic health of the progeny remains underexplored. Here, we investigated the impact of paternal high-protein diet (HPD, 43.2% protein) consumption on the endocrine pancreas and the metabolic phenotype of offspring. Male Wistar rats were given HPD or standard diet (SD, 18.9% protein) for two months. The progenies (F1) were studied at fetal stage and in adulthood. Body weight, glycemia, glucose tolerance (GT), glucose-induced insulin secretion in vivo (GIIS) and whole-body insulin sensitivity were assessed in male and female F1 offspring. Insulin sensitivity, GT and GIIS were similar between F1 females from HPD (HPD/F1) and SD fathers (SD/F1). Conversely, male HPD/F1 exhibited increased insulin sensitivity (p < 0.05) and decreased GIIS (p < 0.05) compared to male SD/F1. The improvement of insulin sensitivity in HPD/F1 was sustained even after 2 months of high-fat feeding. In male HPD/F1, the β cell mass was preserved and the β cell plasticity, following metabolic challenge, was enhanced compared to SD/F1. In conclusion, we provide the first evidence of a sex-specific impact of paternal HPD on the insulin sensitivity and GIIS of their descendants, demonstrating that changes in paternal nutrition alter the metabolic status of their progeny in adulthood.

Enhanced hepatic cholesterol accumulation induced by maternal betaine exposure is associated with hypermethylation of CYP7A1 gene promoter

PURPOSE

Betaine contains three methyl groups and plays a critical role in regulating glucose and lipid metabolism via epigenetic modifications. However, it is unclear whether prenatal betaine intake could affect cholesterol metabolism of progeny through DNA methylation.

METHODS

Hence, pregnant rats were randomly divided into control and betaine groups fed standard diet or 1% betaine supplementation diet, respectively, throughout gestation and lactation.

RESULTS

Maternal betaine exposure significantly (P < 0.05) increased serum and hepatic cholesterol contents but not triglyceride levels in offspring rats. Accordantly, maternal intake of betaine markedly downregulated (P < 0.05) hepatic cholesterol 7 alpha-hydroxylase (CYP7A1) expression at both the mRNA and protein level, while the protein content of low-density lipoprotein receptor (LDLR) was upregulated in the liver of betaine-exposed rats. In addition, prenatal betaine supplementation extremely increased (P < 0.05) hepatic betaine-homocysteine methyltransferase (BHMT) expression at the mRNA and protein level but not affected the expression of other key enzymes involved in methionine metabolism. Furthermore, hepatic hypermethylation of CYP7A1 gene promoter was observed in progeny rats derived from betaine-supplemented dams.

CONCLUSIONS

Our results provide evidence that maternal betaine supplementation significantly enhances hepatic cholesterol contents accompanied with alterations of cholesterol metabolic genes and hypermethylation in offspring rats at weaning.