engleski

In vitro model of bone growth supported by bioglass and 4-hydroxynonenal

Healing of long bones and large joints is often extended or incomplete primarily in elderly people or in polytraumatized patients. Therefore, various attempts are done to solve this severe medical and social problem by the development of novel bioactive materials, among which bioactive glass is attractive because of its osteoconductive properties. On the other hand, lipid peroxidation was defined as an important parameter of systemic stress response in patients with traumatic brain injury and bone fractures, often accompanied by hypertrophic callus formation and heterotopic ossifications. The major bioactive marker and end product of lipid peroxidation, 4-hydroxynonenal (HNE), acts as a second messenger of free radicals and signaling molecule interfering with the activity of cytokines. Hence we carry studies of molecular mechanisms of lipid peroxidation associated with bone growth regulation. Our aim was to use HNE for functionalization of bioactive glass and thus develop further an in vitro model for enhanced osteogenesis. We use a human osteosarcoma HOS cell line as a human bone cell model and two different types of bioactive glasses: 45S5 and 1393, as well as normal glass for a reference. Cell growth, proliferation and differentiation are investigated on non-functionalized and on functionalized bioactive glasses and plain glass. Functionalization is done with HNE and combination of HNE plus bovine serum albumin (BSA) at different concentrations. Cell proliferation is estimated by the trypan-blue exclusion test assay while cell differentiation is determined with the alkaline phosphatase (ALP) staining method. Visual observation has shown a difference in morphology of cells grown on normal and bioactive glasses. Our results illustrate a difference upon cell proliferation and differentiation comparing the type of glasses and the HNE-functionalization used. Thus, HNE may become a bioactive tool for mod ulation of bone cell growth aiming to obtain control of enhanced osteogenesis. HNE may affect the growth of cultured human bone cells. HNE is particularly interesting because it regulates differentiation, proliferation and apoptosis of cells and may accordingly play an important role regulating regeneration of damaged tissue such as bone.

bone growth; 4-hydroxynonenal; bioactive glass

DOI: 0.1016/j.bone.2009.03.454