Efficacy of horse chestnut leaf extract ALH-L1005 as a matrix metalloproteinase inhibitor in ligature-induced periodontitis in canine model

Matrix metalloproteinases (MMPs) are the main proteinases associated with periodontal tissue destruction and remodeling. Therefore, inhibition of host-derived MMPs has a key role in the prevention and reduction of periodontitis progression. Horse chestnut (Aesculus hippocastanum L.) extracts have been used as treatments for inflammatory disease, traditionally. This study assessed the clinical effect as a MMP inhibitor of horse chestnut leaf extract ALH-L1005 on periodontitis. ALH-L1005 was obtained from horse chestnut leaf and its MMP inhibitory activities estimated. Periodontitis was induced in beagles assigned to 4 groups and medicated for 6 weeks: low dose test (LT; ALH-L1005, 100 mg/kg/day), high dose test (HT; ALH-L1005, 200 mg/kg/day), positive control (PC; doxycycline, 10 mg/kg/day), or negative control (NC; placebo). Before and after administration, clinical indices of the teeth and MMP quantity in gingival tissues using zymography were measured. Clinical conditions of the LT, HT, and PC groups were significantly improved after 6 weeks. In zymographic evaluations, gelatinolytic and caseinolytic activities were suppressed in LT, HT, and PC groups but not in the NC group. The results suggest that ALH-L1005 could be an effective agent for clinical prevention and treatment of periodontitis by inhibiting the gelatinase and collagenase activities, which can detach periodontal ligaments from alveolar bone.

Effects of conditioned media from human amniotic epithelial cells on corneal alkali injuries in rabbits

This study was performed to evaluate the effects of conditioned media (CM) from human amniotic epithelial cells (HAECs) on the corneal wound healing process. Eighteen rabbits (36 eyes) were used and randomly assigned to three groups according treatment: CM from HAECs (group 1), vehicle alone (group 2), and saline (group 3). Corneal alkali injuries were induced with 1 N sodium hydroxide. Each reagent used for treatment evaluation was injected into the dorsal bulbar subconjunctiva and the area of the corneal epithelial defect was measured every other day. Two animals from each group were euthanized at a time on days 3, 7, and 15, and the cornea was removed for histological examination. The sum of the epithelial defect areas measured on day 0 to day 6 as well as day 0 to day 14 in group 1 was significantly smaller than those of other groups. Histological examination revealed that the group 1 corneas had less inflammatory cell infiltration and showed more intact epithelial features compared to the other groups. These results suggest that CM from HAECs promote corneal wound healing in rabbits.

A modified method for inducing periodontitis in dogs using a silk-wire twisted ligature

This study was designed to assess the effectiveness of a modified silk ligature twisted with wire for inducing advanced periodontitis. Periodontitis was induced in five premolars and one molar of 20 healthy dogs over a 60-day period. The dogs were divided into four groups according to the ligature-inducing materials used: soft moistened food only, wire ligature (WL), silk ligature (SL) and twisted ligature with silk and wire (SWL). Periodontal indices were recorded, and dental radiographs were taken before and after 60 days of ligation. The ligatures were checked daily and the day the ligature fell out was noted. The period during which the ligatures were maintained was significantly shorter for the SL group compared to the SWL group (p < 0.05). Results of the clinical examination showed that almost all periodontal status parameters including the plaque index, gingival index, clinical attachment level, and bleeding on probing were significantly exacerbated in the SWL group compared to the other groups (p < 0.05). Radiographic evaluation demonstrated that alveolar bone levels were significantly lower in the SWL group than the other groups on day 60 (p < 0.05). These results suggested that experimental periodontitis induced by SWL could be an effective method for investigating periodontitis in canine models.