Endocrine Abstracts

Obesity and type II diabetes have been linked to several health issues, including an increased risk of bone fractures. It is well known that an increase of visceral fat affects bone health causing fragility, mechanical strength reduction and increased propensity of fractures because of impaired bone matrix microstructure and aberrant bone cells function. Adult Danio rerio (zebrafish) represents a powerful model to study fat and bone metabolism. Then, the aim of this study was to evaluate bone and metabolic effects of high fat diet in adult zebrafish. Fish blood glucose levels have been monitored in time course experiments and glycaemia curve was found altered in fat fish compared to non-fat ones (Figure 1). The adult bone remodeling has been evaluated in fish using the scales as read-out system. The scales of high-fat diet fish shown bone resorption lacunae associated with an intense osteoclast activity. In addition, high-fat fish scales shown a significant decrease of alkaline phosphatase (ALP) activity and increase of tartrate-resistant acid phosphatase (TRAP) activity. These data suggests that an imbalance in fat metabolism leads to an alteration of glucose metabolism and an osteoporotic-like phenotype in adult zebrafish. The zebrafish model of obesity can contribute to elucidate in vivo the molecular mechanisms of metabolic changes derived from a high fat diet, which influence the bone tissues regulation and insulin signaling in human obese patients.

Figure 1