Transaminase activities of gingiva in scurvy

Association of gingival crevicular fluid and serum intracytoplasmic enzyme levels in periodontally healthy homozygous (major) beta-thalassemia patients

OBJECTIVE

To assess tissue necrosis in beta-thalassemia major patients, as in other areas of medicine, lactate dehydrogenase (LDH), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) have been widely used. These markers of tissue degradation have also been studied in the gingival crevicular fluid (GCF) in relation to periodontal disease status. The purpose of this study was to investigate whether periodontal diagnostic tests based on these markers of tissue degradation are influenced from the enzymes' levels in serum and, therefore, could be used in the assessment of the patient's periodontal status.

MATERIAL AND METHODS

Forty-four periodontally healthy, homozygous beta-thalassemia patients were enrolled in the study. GCF and serum samples were obtained and the levels of AST, ALT and LDH were determined; the measurements took place in an automated analyzer (Hitachi 777) using the kits of Roche Company.

RESULTS

Lack of correlations between serum and GCF enzyme levels was demonstrated. Serum LDH and serum AST, serum AST and serum ALT are significantly positively correlated. Concerning the GCF, AST and ALT were proved to be significantly positively correlated.

CONCLUSIONS

Elevated values of LDH, ALT and AST in serum do not constitute a confounding factor in GCF measurements of the respective enzymes.

Relationship between crevicular aspartate aminotransferase levels and periodontal disease progression

BACKGROUND

Aspartate aminotransferase (AST), an enzyme released from necrotic cells, has been identified in gingival crevicular fluid (GCF), and elevated levels are associated with periodontal tissue destruction. The aim of this study was to examine the relationship between elevated GCF levels of AST and periodontal disease progression.

METHODS

Over a 12-month period, 8 to 10 interproximal sites in 41 periodontitis subjects (PS) and 15 healthy subjects (HS) were monitored. Clinical measurements included relative attachment level (RAL), probing depth, and bleeding on probing (BOP). Semiquantitative levels of GCF AST (< 800 microIU, > or = 800 microIU, and > or = 1,200 microIU) were determined using a chairside assay. At the 6- and 12-month visits, scaling and root planing and prophylaxis were performed in the PS and HS, respectively. Sensitivity, specificity, positive predictive values (PPV), and negative predictive values (NPV) were calculated for 2 diagnostic criteria (AST > or = 800 microIU, AST > or = 1,200 microIU) utilizing 4 thresholds of disease progression as determined by 2 methods (absolute change in relative attachment level and cumulative sum [CUSUM]).

RESULTS

The percentage of sites exhibiting AST > or = 800 microIU, AST > or = 1,200 microIU, and BOP in the PS was significantly (P<0.02) lower at 6 and 12 months compared to baseline. The use of crevicular AST activity to monitor periodontal disease progression was associated with many false-positive results. Overall, low specificities, PPV, and odds ratios were demonstrated by the assay when using 2 diagnostic criteria and 4 thresholds of disease progression. The high NPV suggest that a negative AST test result was indicative of a periodontally stable site.

CONCLUSIONS

These results demonstrate that elevated levels of AST were present at sites that did not subsequently exhibit disease progression. The high prevalence of AST-positive sites due to gingival inflammation diminished the test's ability to discriminate between progressive and stable, but inflamed, sites.

Aspartate aminotransferase increases in crevicular fluid during experimental periodontitis in beagle dogs

A ligature-induced periodontitis model employing the beagle dog was used to study the levels of aspartate aminotransferase (AST) in crevicular fluid before and after ligation. A significant increase in AST level occurred in crevicular fluid 2 weeks after ligation whereas no increase of enzyme was found in serum. Enzyme levels in crevicular fluid were 10- to 100-fold higher than in serum. Dental plaque did not appear to be the source of the enzyme. Since aspartate aminotransferase has been documented as a marker of cellular injury arising during heart disease and liver disease, this study suggests that aspartate aminotransferase, in like fashion, reflects cellular damage arising from active periodontal disease.

Deficiency of coenzyme Q 10 in gingival tissue from patients with periodontal disease

The specific activities of the succinate dehydrogenase-coenzyme Q(10) reductase in gingival tissue from patients with periodontal disease have been compared with the corresponding specific activities of normal human periodontal tissue. The gingival biopsies from patients having diseased periodontal tissue showed a deficiency of coenzyme Q(10), in contrast to those of the normal periodontal tissue which showed no deficiency. The presence or absence of a deficiency of coenzyme Q(10) in the succinate-coenzyme Q(10) enzyme system is appraised by determining the specific activity in the absence and again in the presence of exogenous coenzyme Q(3). An increase in specific activity of this mitochondrial enzyme system in the presence of exogenous coenzyme Q(3) reflects the mitochondrial deficiency of coenzyme Q(10). Such increases ranged from 38-120% and averaged 81% for the individuals with periodontal disease, and were highly significant statistically. These data correlate with clinical studies in Japan that have indicated a therapeutic benefit of the administration of coenzyme Q(7) to many patients with severe and destructive periodontal disease and with the benefit of administration of hexahydrocoenzyme Q(4) to one such patient in the current work.