Protective effects of baicalin on ligature-induced periodontitis in rats.
OBJECTIVE
Baicalin is a flavonoid compound purified from the medicinal plant, Scutellaria baicalensis Georgi, and has been reported to possess anti-inflammatory and antioxidant activities. The purpose of this study was to test the ability of baicalin to influence the progression of experimental periodontitis in rats, as well as the expression of cyclooxygenase-2 and inducible nitric oxide synthase.


METHODS
Adult male Sprague-Dawley rats were subjected to placement of a nylon thread around the bilateral lower first molars and killed after 7 d. Baicalin (50, 100 or 200 mg/kg) was supplied to the animals by oral gavage, starting 1 d before the induction of periodontitis. The ligature group consisted of rats subjected to periodontitis and receiving vehicle (0.5% carboxymethylcellulose) alone. The alveolar bone loss and the area fraction occupied by collagen fibers were assessed. The expression of cyclooxygenase-2 and inducible nitric oxide synthase protein in the gingiva were detected by immunohistochemistry and western blotting.


RESULTS
Baicalin-treated groups presented with lower alveolar bone loss than that of the ligature group, reaching statistical significance at the dose of 200 mg/kg (p = 0.009). The area fraction of collagen fibers was significantly higher in the baicalin (200 mg/kg)-treated group than in the ligature group (p = 0.047). Baicalin treatment significantly down-regulated the protein expression for cyclooxygenase-2 (p = 0.000) and inducible nitric oxide synthase (p = 0.003), compared with the ligature group.


CONCLUSIONS
Baicalin protects against tissue damage in ligature-induced periodontitis in rats, which might be mediated, in part, by its inhibitory effect on the expression of cyclooxygenase-2 and inducible nitric oxide synthase. These activities could support the continued investigation of baicalin as a potential therapeutic agent in periodontal disease.
Cai
X
X
Department of Periodontology, School and Hospital of Stomatology, Key Laboratory for Oral Biomedical Engineering of Ministry of Education, Wuhan University, Wuhan, China.
Li
C
C
Du
G
G
Cao
Z
Z
D016301:Alveolar Bone Loss / Q000188:drug therapy* / Q000517:prevention & control; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use*; D051546:Cyclooxygenase 2 / Q000187:drug effects* / Q000378:metabolism; D005419:Flavonoids / Q000627:therapeutic use*; D005881:Gingiva / Q000737:chemistry / Q000187:drug effects; D008026:Ligation; D008297:Male; D008336:Mandibular Diseases / Q000188:drug therapy / Q000517:prevention & control; D052247:Nitric Oxide Synthase Type II / Q000187:drug effects* / Q000378:metabolism; D010518:Periodontitis / Q000188:drug therapy* / Q000209:etiology; D051381:Rats; D017207:Rats, Sprague-Dawley
D000894:Anti-Inflammatory Agents, Non-Steroidal; D005419:Flavonoids; C038044:baicalin; D052247:Nitric Oxide Synthase Type II; D051546:Cyclooxygenase 2