Targets for steroid hormone mediated actions of periodontal pathogens, cytokines and therapeutic agents: some implications on tissue turnover in the periodontium.

Abstract

This review attempts to encapsulate the relevance of steroid hormone action in the periodontal tissues, during inflammation, repair and in response to current treatment modalities. Periodontal pathogens metabolise steroid hormones which could contribute to their nutritional requirements and host evasion mechanisms, by forming capsular proteins; their culture supernatants stimulate the synthesis of physiologically active steroid hormones by fibroblasts, which aid inflammatory repair. The functions of glucocorticoids, androgens, oestrogen and progesterone on connective tissue and bone, are applicable to the periodontium, being target tissue. This results in physiological effects on these tissues, during puberty, the menstrual cycle, pregnancy and the menopause. The effects of oral contraceptives and hormone replacement therapy on the periodontium have focused interest in the relationship between sex steroid hormones and periodontal health. Receptor expression and the role of the specific enzyme inhibitors, such as the anti-androgen finasteride and the anti-oestrogen tamoxifen, confirm target tissue activity for steroid hormones in the periodontium. The pro-anabolic and anti-inflammatory actions of tetracyclines, are an intriguing model for hormone mediated pathways of action. The effects of the specific alkaline phosphatase inhibitor levamisole on matrix turnover are linked to steroid hormone action, with direct implications on the healing periodontium. Drugs which contribute to gingival overgrowth are an interesting model, for explanation of an exaggerated 'scar tissue' response mediated by hormones, cytokines and a variety of enzyme systems. Cell dynamics of the periodontium plays an important role in co-ordinating the diverse interactions between steroid hormones and therapeutic agents.