RESUMEN
BACKGROUND: This study evaluated the ameliorative effect of hesperidin (HES), an anti-inflammatory flavanone, in rats with ligation (Lig)-induced periodontitis. METHODS: A total of 48 rats were randomly divided into non-ligation group (NL), Lig group, and two ligation-plus-HES groups (L+H). HES was administered immediately after ligature placement at a dose of 75 or 150 mg/kg by intragastric feeding. Destruction of the ligated maxillary second and mandibular first molars were evaluated by dental radiography, microcomputed tomography (micro-CT), and histometry performed after sacrificing the rats on the seventh day. The expression levels of interleukin (IL)-1ß, IL-6, and inducible nitric oxide synthase (iNOS) messenger (m)RNAs in the gingiva were determined by reverse-transcription polymerase chain reaction. The expression of iNOS was examined by immunohistochemistry. RESULTS: The dental radiography and micro-CT findings revealed significantly increased alveolar bone loss in the Lig group, which was significantly prevented by HES. The histometry results revealed less gingival inflammation and connective tissue loss in the L+H groups compared with that in the Lig group. The mRNA expression levels of IL-6, IL-1 ß, and iNOS were significantly increased in the Lig group but were reduced in the L+H groups. The immunostaining results showed that the ligation-induced iNOS expression was also decreased by HES. CONCLUSIONS: Oral administration of HES promotes an ameliorative effect against the ligation-induced alveolar bone loss and effectively inhibits the production of proinflammatory mediators in rats with experimentally induced periodontitis. Therefore, HES may be a good candidate for modulating oral inflammatory diseases.