Stimulation of bone resorption by the kallikrein-kinin system and the coagulation cascade

Abstract

The activities of bone forming osteoblasts and bone resorbing osteoclasts are regulated in physiological bone metabolism by several endocrine and paracrine factors, including peptide and steroid hormones as well as a variety of cytokines and growth factors (reviewed by Vaes 1988, Suda et al. 1992). Recently it has been demonstrated that also protooncogenes (c-fos and c-src) are involved in the regulation of bone cell activities (reviewed by Suda et al. 1995). Several pathological conditions, e.g. inflammation, tumors, Paget disease, intraosseous cysts, hyperparathyroidism, osteoporosis, also influence the activity of bone cells by the release of endocrine and paracrine factors. This may give rise to loss of bone tissue or to new bone formation. Inflammatory processes in the vicinity of the skeleton, e.g. rheumatoid arthritis, periodontitis and osteomyelitis, frequently result in loss of bone. The disappearance and changes in the architecture of bone tissue in these diseases are mostly a result of locally activated bone resorbing osteoclasts, although inhibition of bone forming osteoblasts also may contribute.