Dataset Information

Insulin receptor signaling in osteoblasts regulates postnatal bone acquisition and body composition

ABSTRACT: Global energy balance in mammals is controlled by the actions of circulating hormones that coordinate fuel production and utilization in metabolically active tissues. Bone-derived osteocalcin, in its undercarboxylated, hormonal form, regulates fat deposition and is a potent insulin secretagogue. Here, we show that insulin receptor (IR) signaling in osteoblasts controls osteoblast development and osteocalcin expression by suppressing the Runx2 inhibitor Twist-2. Mice lacking IR in osteoblasts have low circulating undercarboxylated osteocalcin and reduced bone acquisition due to decreased bone formation and deficient numbers of osteoblasts. With age, these mice develop marked peripheral adiposity and hyperglycemia accompanied by severe glucose intolerance and insulin resistance. The metabolic abnormalities in these mice are improved by infusion of exogenous under-carboxylated osteocalcin. These results indicate the existence of a bone-pancreas endocrine loop through which insulin signaling in the osteoblast ensures osteoblast differentiation and stimulates osteocalcin production, which in turn regulates insulin sensitivity and pancreatic insulin secretion to control glucose homeostasis. We used microarrays to detail the global gene expression changes in response to insulin acting through insulin receptor in osteoblasts and identified distinct genes specifically involved in bone remodeling process.

ORGANISM(S): Mus musculus

PROVIDER: GSE21710 | GEO | 2010/05/07

SECONDARY ACCESSION(S): PRJNA127163

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Paleoproteomics and the study of ancient proteins has become an important consideration in bioarchaeological research as we seek to understand the relationship between the physical skeleton and its underlying biochemistry. Osteocalcin (OC) is an abundant, non-collagenous protein that is accessible archaeologically due to its affinity for hydroxyapatite in bone. Manufactured by the osteoblast cells during normal bone metabolism, osteocalcin is inherently linked to the process of bone remodelling. Clinical studies have consistently shown the impact of biological (i.e., sex and age) and pathological (i.e., disease) factors on osteocalcin concentrations within the body; however, this connection has yet to be fully explored bioarchaeologically. For this study, 46 individuals from the Danish Sct. Albert’s cemetery (AD 1250-1536) were analyzed with cortical bone samples harvested from the femur. Each sample was demineralized and quantified using established paleoproteomic methods (ELISA) and tested for diagenesis using FTIR-ATR. 4 samples were validated by LC-MS. No significant differences were found in the osteocalcin concentrations between adult males and females. However, males had a wider range of osteocalcin variability perhaps explained in part by their increased prevalence of pathological conditions characterized by bone remodelling. Similarly, non-adults had a wide range of osteocalcin variability but there were no significant differences when compared to the adult mean. No correlations were found between osteocalcin concentrations and diagenesis suggesting that the protein can survive across a range of temporal periods and variable burial environments. While no clear pattern emerged between osteocalcin concentrations and biological and/or pathological factors, this study is significant in that it further explores the use of paleoproteomics in bioarchaeological contexts and how we may unite our macroscopic and biochemical assessments of human skeletal remains.

Dataset Information

Insulin receptor signaling in osteoblasts regulates postnatal bone acquisition and body composition

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure