title: Drug-induced gingival overgrowth--a review.
abstract: Drug-induced gingival overgrowth is a side effect associated with 3 types of drugs: anticonvulsants (phenytoin), immunosuppressive agents (cyclosporine A), and various calcium channel blockers for cardiovascular diseases. Gingival overgrowth is characterized by the accumulation of extracellular matrix in gingival connective tissues, particularly collagenous components with various degrees of inflammation. Although the mechanisms of these disorders have not been elucidated, recent studies suggest that these disorders seem to be induced by the disruption of homeostasis of collagen synthesis and degradation in gingival connective tissue, predominantly through the inhibition of collagen phagocytosis of gingival fibroblasts. The integrins are a large family of heterodimeric transmembrane receptors for extracellular matrix molecules. alpha2beta1 integrin serves as a specific receptor for type I collagen on fibroblasts, and alpha2 integrin has been shown to play a crucial role in collagen phagocytosis. Actin filaments, which are assembled from monomers and oligomers, are involved in collagen internalization after binding to integrins. Furthermore, the implication of intracellular calcium in the regulation of integrin-mediated binding activity and gelsolin activity, known as a calcium-dependent actin-severing protein, is also described. In this review, we focus on collagen metabolism in drug-induced gingival overgrowth, focusing on the regulation of collagen phagocytosis in fibroblasts.
authors.affiliation: Division of Gene Expression, Institute for Genome Research, The University of Tokushima; 3-18-15 Kuramoto, Tokushima 770-8503, Japan. kataoka@genome.tokushima-u.ac.jp
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Kataoka
authors.forename: Jun-ichi
authors.initials: J
authors.lastname: Kido
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Shinohara
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Nagata
mesh_terms: D000927:Anticonvulsants / Q000009:adverse effects*; D002118:Calcium / Q000502:physiology; D002121:Calcium Channel Blockers / Q000009:adverse effects*; D024042:Collagen Type I / Q000378:metabolism; D005881:Gingiva / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D006801:Humans; D007166:Immunosuppressive Agents / Q000009:adverse effects*; D039421:Integrin alpha2 / Q000502:physiology; D010587:Phagocytosis / Q000502:physiology
chemical_list: D000927:Anticonvulsants; D002121:Calcium Channel Blockers; D024042:Collagen Type I; D007166:Immunosuppressive Agents; D039421:Integrin alpha2; D002118:Calcium