Hydroxyproline and Total Protein Levels in Gingiva and Gingival Crevicular Fluid in Periodontally Healthy Human Subjects.

Abstract

Age is known to be one of the factors which affect the rate of collagen and protein turnover in the connective tissues of the periodontium. The aim of the present study was to determine the levels of hydroxyproline (Hyp) and total protein in both the gingiva and gingival crevicular fluid (GCF) of periodontally healthy human subjects of two different age groups. The subjects of the young group were selected from among patients scheduled for extraction of upper and lower first or second premolars for orthodontic reasons. The second (older) group included individuals whose teeth were to be extracted for endodontic reasons. GCF was obtained before gingival sampling. The tissues surrounding the sockets were harvested immediately after extraction of the indicated teeth. All samples were analyzed biochemically. No significant difference was found in gingival and GCF levels of Hyp (which is unique to collagen) between the groups. Total protein levels in gingiva were significantly higher in the young group than in the older group. GCF total protein levels showed no significant difference between the groups. The higher gingival protein levels in the younger group seem to conform to previous findings.

Gingival crevicular fluid protein content and alkaline phosphatase activity in relation to pubertal growth phase

“…In contrast, no differences in total GCF protein content were seen. 9 The lack of significant changes in total GCF protein content is consistent with the hypothesis that the amount of GCF, ie, the flow rate, is not sensitive to the different growth phases. Therefore, the GCF volume would also not be expected to be influenced by the pubertal growth phase.…”

“…Although not using any method for precise assessment of the individual growth phases, a previous study 9 reported greater gingival total protein content in growing subjects as compared with an older group. In contrast, no differences in total GCF protein content were seen.…”

“…during pubertal growth, 8 and the total protein content of the GCF has been reported to be greater in growing subjects as compared with an older group. 9 More recently, total GCF alkaline phosphatase (ALP) activity has been shown to be related to the pubertal growth spurt and has thus been proposed as a noninvasive diagnostic aid for the determination of optimal treatment timing in functional jaw orthopedics. 10 However, no studies have investigated whether the total GCF protein content is sensitive to the different growth phases, nor which of the total or normalized GCF ALP activities might be better suited as a biomarker for the pubertal growth phase.…”

Gingival Crevicular Fluid Biomarkers in Patients with Gingivitis and Chronic Periodontitis

“…Zymography evidenced differences between healthy and diseased subjects. Akalin et al (1992) 9) found that Hyp levels in gingival tissue and GCF from periodontally healthy human subjects of different age groups were higher in a younger group than in an older one.…”

“…Collagenases are associated with tissue destruction in periodontal disease; they degrade collagen and are also present in GCF, saliva and gingival tissue 7,8) . Since hydroxyproline (Hyp) is a specific amino acid of collagen, its detection in GCF is therefore considered a sign of destruction of gingival connective tissue 9) .…”