Common Dietary Modifications in Preclinical Models to Study Skeletal Health

Abstract

Bone is a highly dynamic tissue that undergoes continuous remodeling by bone resorbing osteoclasts and bone forming osteoblasts, a process regulated in large part by osteocytes. Dysregulation of these coupled catabolic and anabolic processes as in the case of menopause, type 2 diabetes mellitus, anorexia nervosa, and chronic kidney disease is known to increase fracture risk. Recent advances in the field of bone cell metabolism and bioenergetics have revealed that maintenance of the skeleton places a high energy demand on these cells involved in bone remodeling. These new insights highlight the reason that bone tissue is the beneficiary of a substantial proportion of cardiac output and post-prandial chylomicron remnants and requires a rich supply of nutrients. Studies designed for the specific purpose of investigating the impact of dietary modifications on bone homeostasis or that alter diet composition and food intake to produce the model can be found throughout the literature; however, confounding dietary factors are often overlooked in some of the preclinical models. This review will examine some of the common pre-clinical models used to study skeletal biology and its pathologies and the subsequent impact of various dietary factors on these model systems. Furthermore, the review will include how inadvertent effects of some of these dietary components can influence bone cell function and study outcomes.

Current Discoveries and Future Implications of Eating Disorders

“…AN is an eating disorder that is characterized by strict restrictions of food intake, leading to abnormally low body weight and an intense fear of gaining weight [12]. While past epidemiological studies have focused on young women in Western countries, anorexia nervosa has been reported in men and women of all ages worldwide.…”

“…AN results in a notable reduction in bone mineral density (BMD) in approximately 40% of patients and a three times increased lifetime fracture risk [12]. Another noticeable skeletal phenotype concerning anorexia is the increased number and size of bone marrow adipocytes despite a lipodystrophic response.…”

“…Clinically, there is a general negative correlation between BMD and bone marrow adipose tissue (BMAT). Unique fat depots are of particular interest in AN study [12]. Bone health in adolescents with AN has been extensively reviewed [15].…”