Investigation of the effect of astaxanthin on alveolar bone loss in experimental periodontitis.

BACKGROUND AND OBJECTIVE: Astaxanthin is a keto-carotenoid that has a strong antioxidant effect. The purpose of this study was to evaluate the effects of astaxanthin on alveolar bone loss and histopathological changes in ligature-induced periodontitis in rats.

MATERIAL AND METHODS: Wistar rats were divided into four experimental groups: non-ligated (C, n = 6); ligature only (L, n = 6); ligature and astaxanthin (1 mg/kg/day astaxanthin, AS1 group, n = 8); ligature and astaxanthin (5 mg/kg/day astaxanthin, AS5 group, n = 8). Silk ligatures were placed at the gingival margin of lower first molars of the mandibular quadrant. The study duration was 11 days and the animals were killed at the end of this period. Changes in alveolar bone levels were clinically measured and tissues were immunohistochemically examined, osteocalcin, bone morphogenic protein-2, inducible nitric oxide synthase, Bax and bcl-2 levels in alveolar bone and tartrate-resistant acid phosphatase-positive osteoclast cells, osteoblast and inflammatory cell counts were determined.

RESULTS: Alveolar bone loss was highest in the L group and the differences among the L, AS1 and AS5 groups were also significant (P < .05). Both doses of astaxanthin decreased tartrate-resistant acid phosphatase-positive+ osteoclast cell and increased osteoblast cell counts (P < .05). The inflammation in the L group was also higher than those of the C and AS1 groups were (P < .05) indicating the anti-inflammatory effect of astaxanthin. Although inducible nitric oxide synthase, osteocalcin, bone morphogenic protein-2 and bax staining percentages were all highest in the AS5 group and bcl-2 staining percentage was highest in the AS1 group, values were close to each other (P > .05).

CONCLUSION: Within the limits of this study, it can be suggested that astaxanthin administration may reduce alveolar bone loss by increasing osteoblastic activity and decrease osteoclastic activity in experimental periodontitis model.