Role of polydeoxyribonucleotide (PDRN) in the treatment of experimental periodontitis

Objectives: To investigate the possible beneficial effect of a novel compound, polydeoxyribonucleotide (PDRN), in a well established rat model of experimental periodontitis. Methods: Male Sprague-Dawley rats (380-450 grams) were anesthetized with sodium pentobarbital (50mg/kg), mouth was open by using a retractor and a 4-0 silk suture was placed around the cervix of the lower left first molar and knotted medially. A group of animals was used as sham-operated controls. All animals were kept under normal environmental conditions for all the duration of the experiment and fed with smooth and sweet food in order to help the progression of periodontitis. After 7 days all animals were randomized to receive daily PDRN (oral gel containing a 25% mixture of polydeoxyribonucleotides) or its vehicle (a saline solution based gel) for 7 days. At the end of the experiment animals were sacrificed and the periodontal tissues excised and stored for histological and bio-molecular analysis. The contralateral tissues (right side) were used as internal control.Results:Histological findings confirmed the presence of periodontitis in saline-treated animals characterized by a strong inflammatory infiltrate in the gingivomucosal tissue sections compared to sham-operated animals, PDRN markedly reduced inflammation and restored the altered architecture. Molecular analysis (western blot) revealed an increase in Tumor Necrosis Factor-α p-JNK and Bax expression while decreased the anti-apoptotic Bcl-2 protein in saline-treated compared to sham-operated rats. PDRN administration restored the altered Bcl-2 expression and reduced TNF-α p-JNK and Bax expression in gingivomucosal specimens.Conclusions:PDRN might be a potential therapeutic option for patients affected by periodontitis.