The effects of aging and maternal protein restriction during lactation on thymic involution and peripheral immunosenescence in adult mice

Effect of Lactational Low-Protein Diet on Skeletal Muscle during Adulthood and Ageing in Male and Female Mouse Offspring

Sarcopenia is characterised by the loss of skeletal muscle mass and function, which leads to a high risk of increased morbidity and mortality. Maternal malnutrition has been linked to impaired development of skeletal muscle of the offspring; however, there are limited studies that report the long-term effect of a maternal low-protein diet during lactation on the ageing of skeletal muscles. This study aimed to examine how a maternal low-protein diet (LPD) during lactation affects skeletal muscle ageing in the offspring. Pups born from control mothers were lactated by mothers fed with an LPD. Post-weaning, mice were either maintained on an LPD or switched to a control, normal-protein diet (NPD). In males, an LPD mainly affected the size of the myofibres without a major effect on fibre number and led to reduced grip strength in ageing mice (24 months). Female mice from mothers on an LPD had a lower body and muscle weight at weaning but caught up with control mice at 3 months. During ageing, the muscle weight, myofibre number and survival rate of female pups were significantly affected. These findings highlight the effect of an LPD during lactation on skeletal muscle ageing, the lifespan of offspring and the importance of sexual dimorphism in response to dietary challenges.

Protein-restricted maternal diet during lactation decreases type I and type III tropocollagen synthesis in the skin of mice offspring

We investigated the effects of a low protein (LP) maternal diet during lactation on type I and III tropocollagen synthesis in infant mouse skin. The LP diet decreased the levels of type I and III tropocollagen proteins and COL1A1 and COL3A1 mRNA. Thus, the protein composition of the maternal perinatal diet may influence the skin health of offspring.

Nutritional Programming Effects on the Immune System

The relationship between patterns of early growth and age-associated diseases such as type 2 diabetes and cardiovascular disease is well established. There is also strong evidence from both human and animal studies that early environmental factors such as maternal nutrition may influence lifespan. Interestingly, more recent studies have demonstrated that nutritional programming in early life effects immunity, such that altered lifespan can also lead to programmed changes in immune function. Here we describe the use of immunohistology and flow cytometry techniques to study two key immune lymphoid organs: one that is involved in developing immune cells (thymus) and another which is the site of immune activation (spleen).

Nutritional Programming Effects on Development of Metabolic Disorders in Later Life

Developmental programming resulting from maternal malnutrition can lead to an increased risk of metabolic disorders such as obesity, insulin resistance, type 2 diabetes and cardiovascular disorders in the offspring in later life. Furthermore, many conditions linked with developmental programming are also known to be associated with the aging process. This review summarizes the available evidence about the molecular mechanisms underlying these effects, with the potential to identify novel areas of therapeutic intervention. This could also lead to the discovery of new treatment options for improved patient outcomes.

Nutrition in early life and age-associated diseases

The prevalence of age-associated disease is increasing at a striking rate globally. It is known that a strong association exists between a suboptimal maternal and/or early-life environment and increased propensity of developing age-associated disease, including cardiovascular disease (CVD), type-2 diabetes (T2D) and obesity. The dissection of underlying molecular mechanisms to explain this phenomenon, which is known as 'developmental programming' is still emerging; however three common mechanisms have emerged in many models of developmental programming. These mechanisms are (a) changes in tissue structure, (b) epigenetic regulation and (c) accelerated cellular ageing. This review will examine the epidemiological evidence and the animal models of suboptimal maternal environments, focusing upon these molecular mechanisms and will discuss the progress being made in the development of safe and effective intervention strategies which ultimately could target those 'programmed' individuals who are known to be at-risk of age-associated disease.