The Legacy of Parental Obesity: Mechanisms of Non-Genetic Transmission and Reversibility

Effect of Trust in Science on Parental Reactions to Messaging about Children's Epigenetics-Related Obesity Risk

INTRODUCTION

Accumulating evidence suggests that preconception epigenetic changes elevate the risk for obesity throughout the lifespan. Little is known about how parents may react to learning about parent-child epigenetic transmission of obesity risk. Further, it is unclear how trust in science may moderate these responses.

METHODS

We compared risk perceptions, behavioral intentions, perceived control, and information-focused ratings of 322 parents with high weight status who were randomized to read an article about the role of preconception epigenetics in intergenerational obesity risk transmission, versus three comparators that focused on genetics, family environment, or an unrelated topic.

RESULTS

Parents had largely similar reactions to the epigenetics, genetics, and family environment articles in terms of perceived credibility, relevance, and threat response, but the epigenetics article failed to produce the elevated cognitive (F(3, 310) = 3.027, p = 0.030) and affective/intuitive (F(3, 310) = 3.05, p = 0.029) risk perceptions observed in response to the genetics and family environment articles compared to control. Science trust moderated individual reactions to the epigenetics concepts, such that those with low science trust exhibited lower attentiveness to the epigenetics article (F(4, 249) = 2.92, p = 0.022), and groups with low, medium, or high science trust exhibited distinct reaction profiles in terms of affective/intuitive risk perception (F(6, 310) = 2.40, p = 0.028).

CONCLUSION

An audience's trust in science should be considered when tailoring messages about the role of epigenetics in conveying obesity risk from parent to child.

Lipotoxicity and Oocyte Quality in Mammals: Pathogenesis, Consequences, and Reversibility

Metabolic stress conditions are often characterized by upregulated lipolysis and subsequently increased serum free fatty acid (FFA) concentrations, leading to the uptake of FFAs by non-adipose tissues and impairment of their function. This phenomenon is known as lipotoxicity. The increased serum FFA concentrations are reflected in the ovarian follicular fluid, which can have harmful effects on oocyte development. Several studies using in vitro and in vivo mammalian models showed that altered oocyte metabolism, increased oxidative stress, and mitochondrial dysfunction are crucial mechanisms underlying this detrimental impact. Ultimately, this can impair offspring health through the persistence of defective mitochondria in the embryo, hampering epigenetic reprogramming and early development. In vitro and in vivo treatments to enhance oocyte mitochondrial function are increasingly being developed. This can help to improve pregnancy rates and safeguard offspring health in metabolically compromised individuals.

Bee Pollen Phytochemicals and Nutrients as Unequaled Pool of Epigenetic Regulators: Implications for Age-Related Diseases

Bee pollen is characterized by an exceptional diversity and abundance of micronutrients and bioactive phytochemicals. This richness remains very sparsely investigated, but accumulating evidence strongly supports a promising future for bee pollen in human nutrition and medicine. Epigenetic regulation is among the most compelling biomedical topics that remain completely untapped in bee pollen and bee derivative research. In our current research, we identified numerous ubiquitous compounds that are consistently present in this matrix, regardless of its botanical and geographical origins, and that have been well studied and documented as epigenetic regulators in recent years. Given the relative newness of both bee pollen biomedical research and epigenetic studies within nutritional, pharmaceutical, and medical sciences, this review aims to bridge these valuable fields and advance related experimental investigations. To the best of our knowledge, this is the first work that has aimed to comprehensively investigate the epigenetic modulatory potential of bee pollen compounds. Our findings have also unveiled several intriguing phenomena, such as a dual effect of the same compound depending on the cellular context or the effect of some compounds on the cross-generational heritability of epigenetic traits. Although experimental studies of epigenetic regulation by bee pollen as a whole or by its extract are still lacking, our current study clearly indicates that this research avenue is very promising and worth further investigations. We hope that our current work constitutes a foundational cornerstone of future investigations for this avenue of research.

Paternal impact on the developmental programming of sexual dimorphism

Sexual dimorphism involves distinct anatomical, physiological, behavioral, and developmental differences between males and females of the same species, influenced by factors prior to conception and during early development. These sex-specific traits contribute to varied phenotypes and individual disease risks within and across generations and understanding them is essential in mammalian studies. Hormones, sex chromosomes, and imprinted genes drive this dimorphism, with over half of quantitative traits in wildtype mice showing sex-based variation. This review focuses on the impact of paternal non-genetic factors on sexual dimorphism. We synthesize current research on how paternal health before conception affects offspring phenotypes in a sex-specific manner, examining mechanisms such as DNA methylation, paternally imprinted genes, sperm RNA, and seminal plasma. Additionally, we explore how paternal influences indirectly shape offspring through maternal behavior, uterine environment, and placental changes, affecting males and females differently. We propose mechanisms modulating sexual dimorphism during development, underscoring the need for sex-specific documentation in animal studies.

Thermoneutral Housing Enables Studies of Vertical Transmission of Obesogenic Diet-Driven Metabolic Diseases

Vertical transmission of obesity is a critical contributor to the unabated obesity pandemic and the associated surge in metabolic diseases. Existing experimental models insufficiently recapitulate "human-like" obesity phenotypes, limiting the discovery of how severe obesity in pregnancy instructs vertical transmission of obesity. Here, via utility of thermoneutral housing and obesogenic diet feeding coupled to syngeneic mating of WT obese female and lean male mice on a C57BL/6 background, we present a tractable, more "human-like" approach to specifically investigate how maternal obesity contributes to offspring health. Using this model, we found that maternal obesity decreased neonatal survival, increased offspring adiposity, and accelerated offspring predisposition to obesity and metabolic disease. We also show that severe maternal obesity was sufficient to skew offspring microbiome and create a proinflammatory gestational environment that correlated with inflammatory changes in the offspring in utero and adulthood. Analysis of a human birth cohort study of mothers with and without obesity and their infants was consistent with mouse study findings of maternal inflammation and offspring weight gain propensity. Together, our results show that dietary induction of obesity in female mice coupled to thermoneutral housing can be used for future mechanistic interrogations of obesity and metabolic disease in pregnancy and vertical transmission of pathogenic traits.

Role of Fish Oil in Preventing Paternal Obesity and Improving Offspring Skeletal Muscle Health

This study investigates the effects of fish oil supplementation during the periconceptional period in male mice. Specifically, it examines the impact of fish oil on intergenerational health, as determined by skeletal muscle markers. To mimic paternal obesity, thirty mice were separated into three groups with distinct dietary regimes for 10 weeks: a high-fat diet (HF), a high-fat diet supplemented with fish oil (FO), and a low-fat diet (LF). Then, these mice mated with control female mice. Dams and offspring consumed a chow diet during gestation and lactation, and the offspring continued on a chow diet. To study short-term (8 weeks) and long-term (16 weeks) effects of FO, skeletal muscle was isolated at the time of sacrifice, and gene analyses were performed. Results suggest that offspring born to FO-supplemented sires exhibited a significant, short-term upregulation of genes associated with insulin signaling, fatty acid oxidation, and skeletal muscle growth with significant downregulation of genes involved in fatty acid synthesis at 8 weeks. Prominent differences in the above markers were observed at 8 weeks compared to 16 weeks. These findings suggest the potential benefits of FO supplementation for fathers during the periconceptional period in reducing the health risks of offspring due to paternal obesity.