High-fat/high-sucrose feeding increases systemic intermediate monocyte population in two rat strains, but major bone changes are observed only in sprague dawley rats

Abstract

Purpose: Monocytes are the circulating precursors of macrophages and osteoclasts and three main monocyte subsets are defined: classical, intermediate and non-classical. The proportion of intermediate monocytes in the blood is known to increase in diseases such as asthma and rheumatoid arthritis, but also during obesity; one of the known risk factor for osteoarthritis (OA). This monocyte subset also has the highest capacity for bone resorption, when differentiated to osteoclasts in vitro. In addition, we know that especially early development of OA is associated with an increased bone resorption and fast remodeling, whereas only at later stages a slow turnover accompanied by subchondral plate thickening or sclerosis can be observed.