title: Age-dependent changes in cell proliferation and cell death in the periodontal tissue and the submandibular gland in mice: a comparison with other tissues and organs.
abstract: This study investigated the age-dependent changes in the number of BrdU- and TUNEL-positive cells in murine gingival tissue and submandibular gland, and compared the findings with those in other tissues and organs. The cell proliferative activity was decreased after 20 weeks of age in epithelial cells of the gingiva, tongue, buccal mucosa and skin. A decreased cell proliferative activity was also associated with aging in the liver and kidney parenchymal cells. Meanwhile, cell death showed peculiar changes in gingival subepithelial tissue, and mucous and serous acini of the submandibular gland. An increase of TUNEL-positive cells was demonstrated in gingival subepithelial tissue after 20-week-old of age. A significant increase of TUNEL-positive cells was also found in the mucous acinar cells in the 20-week-old mice and in the serous acini after 20 weeks. The fluctuation in the number of TUNEL-positive cells in the subepithelial tissue of the skin, and BrdU- and TUNEL-positive staining ratios in the liver was smaller than that in other tissue and organs throughout life. This study may provide useful information for better understanding the influence of aging on the functional alteration that occurs in the gingival tissue and submandibular gland of the elderly.
authors.affiliation: Laboratory of Oral Pathology and Medicine, Department of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Fukuoka 812-8582, Japan.
authors.forename: Norio
authors.initials: N
authors.lastname: Enoki
authors.forename: Tamotsu
authors.initials: T
authors.lastname: Kiyoshima
authors.forename: Takako
authors.initials: T
authors.lastname: Sakai
authors.forename: Ieyoshi
authors.initials: I
authors.lastname: Kobayashi
authors.forename: Keiko
authors.initials: K
authors.lastname: Takahashi
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Terada
authors.forename: Hidetaka
authors.initials: H
authors.lastname: Sakai
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D001973:Bromodeoxyuridine / Q000378:metabolism; D016923:Cell Death; D049109:Cell Proliferation; D004847:Epithelial Cells / Q000166:cytology; D005881:Gingiva / Q000166:cytology; D020287:In Situ Nick-End Labeling; D007668:Kidney / Q000166:cytology*; D007700:Kinetics; D008099:Liver / Q000166:cytology*; D051379:Mice; D009061:Mouth Mucosa / Q000166:cytology; D009928:Organ Specificity; D010519:Periodontium / Q000166:cytology*; D012867:Skin / Q000166:cytology*; D013363:Submandibular Gland / Q000166:cytology*
chemical_list: D001973:Bromodeoxyuridine