Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.23 (beta-galactosidase)
 14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The in vitro life-span of human periodontal ligament fibroblasts (PDLF) was studied on clones from periodontium of teeth extracted due to periodontitis and dental caries (69 clones/192 individuals, aged 20-80 years) and from periodontium of teeth extracted for orthodontic reasons (23 clones/26 individuals, aged 15-19 years). In the primary cultures the ratio of the number of cells expressing senescence-associated beta-galactosidase (SA-beta-Gal) to the total number of cells is significantly larger in PDLF (92 clones; 11.1+/-4.9%) than in human gingival fibroblasts (GF) (10 clones; 0.5+/-0.1 %). The finite population doubling numbers (PD) of PDLF are not age-matched and the mean PD of PDLF (7.1+/-2.9) is significantly smaller than GF (28.5+/-3.2), IMR-90 (human lung fibroblasts, 5 clones; 44.3 +/- 2.2), and human osteoblasts (5 clones; 19.7+/-1.4). Comparing the ratio of the number of SA-beta-Gal positive cells to the total number of cells in primary culture, and the finite PD in PDLF cultures: 1) the ratio of 15-19 years old donor group is significantly smaller than in the other donor groups (20-29, 30-39, 40-49, 50-59 and 60-80 years old), and 2) there were no statistically significant differences among the 20-29, 30-39, 40-49 and 50-59 year old donor groups, and the 30-39, 40-49, 50-59 and 60-80 year old donor groups. These findings suggest that the in vitro life-span of PDLF is shorter than other fibroblasts in the connective tissues and that PDLF may undergo senescence in adult clones without relation to donor's age. There may be more aged fibroblasts in periodontium than in other tissues, such as gingiva and lung.
 ...
PMID:The in vitro life-span of human periodontal ligament fibroblasts. 1085 2

Osteocalcin production of senescent periodontal ligament fibroblasts (PDLF) with the expression of senescence-associated beta-galactosidase (SA-beta-Gal) was investigated on clones from 50-80 years old donors (n=20) with teeth extracted due to periodontitis and dental caries, and from 15-19 year old donors (n=20) with normal teeth extracted for orthodontic reasons. Immunohistochemically, the nonsenescent PDLF in all cultures in passage 2 showed strong reactivity with anti-osteocalcin. The reactive intensity of PDLF (passage 2, PD 3.0) was significantly stronger in 50-80 year old donor group than in 15-19 year old donor group, suggesting that osteocalcin production of PDLF cultured in early passage is larger in cells from adult population than in cells from adolescent population. In PDLF cultures in passage 2 from 50-80 year old donor, two types of senescent cells were found: one with strong reactivity to anti-osteocalcin and the other with little detectable reactivity. The culture consisted of senescent PDLF (passage 8, PD 14.8) did not include cells which have a detectable reactivity with anti-osteocalcin immunohistochemically and the reactive intensity was significantly weaker in the senescent culture than in the culture in passage 2 by ELISA. This suggests that the production potential of osteocalcin is impaired in PDLF with aging in culture. Further, the reactive intensity with anti-osteocalcin of PDLF in passage 2 deprived of serum for 48 h was 6% of that of cells cultured with serum and the reaction increased after serum stimulation, suggesting that the osteocalcin production in PDLF in early passage is implicated in mitogenic stimulation.
 ...
PMID:Impairment of osteocalcin production in senescent periodontal ligament fibroblasts. 1085 6