Effects of a Topically Applied Oral Wound Dressing Film on Intra-oral Wound Healing in Rabbits.

BACKGROUND/AIM: Oral lesions are a common clinical symptom that can impair the quality of life of patients. Several treatments have been developed; however, therapies for wounds on the oral mucosa are symptomatic and unsatisfactory. This study aimed to evaluate the efficacy of an oral wound dressing (OWD) film in healing excision and chemical burns using a rabbit oral wound model and to demonstrate the effect of physical barriers during wound healing. MATERIALS AND METHODS: Excision and chemical burn wounds were induced on the oral hard palate of animals. Four experimental groups were established. The OWD film was applied immediately after surgery and replaced every 24 h over the following 3 days. The animals were sacrificed at 3, 7, and 14 days after surgery. The hard palate tissues were analyzed by histological and immunohistochemical evaluation. The degree of epithelialization, number of proliferating cells, and collagen deposition were evaluated. Statistical significance was analyzed using the Student's t-test. RESULTS: Following application of the OWD film to the excision and chemical burn wounds, the OWD treatment group's epithelial gap and proliferation showed a significant difference compared to those of the untreated group during the proliferative stage of wound healing. However, there was no difference in the epithelial gap in the chemical burn wound model, whereas the OWD treatment group showed a significantly reduced ulcerated area. Collagen deposition in the OWD treatment group was significantly increased during the remodeling stage of wound healing. CONCLUSION: The OWD film treatment promoted wound healing in the oral mucosa by accelerating wound closure and reconstruction.

Potent vasodilation effect of amurensin G is mediated through the phosphorylation of endothelial nitric oxide synthase.

Endothelial nitric oxide synthase (eNOS) has important regulatory functions in vascular tone, and impaired endothelium-dependent vasodilatation is a key event in diabetes and atherosclerosis. Vitis amurensis grapes containing resveratrol oligomers are consumed as wine and fruit and have antioxidative and neuroprotective effects. In this study, our goal was identify the most potent eNOS-activating compound among six stilbenes and oligostilbenes found in V. amurensis and to clarify its molecular mechanism. Among the six tested compounds, amurensin G most potently relaxed endothelium-intact aortic rings and increased eNOS phosphorylation and nitric oxide (NO) production. Amurensin G increased both estrogen receptor (ER) phosphorylation and ER-dependent gene transcription, and ERα or ERß inhibition suppressed amurensin G-mediated eNOS phosphorylation. Amurensin G enhanced the activities of phosphatidylinositol 3-kinase (PI3K) and Src and their chemical inhibitors suppressed amurensin G-stimulated eNOS phosphorylation. Moreover, amurensin G activated AMP-activated protein kinase (AMPK), and amurensin G-stimulated eNOS phosphorylation and PI3K activation were reversed by AMPK inhibition. ER inhibition reversed AMPK-dependent PI3K activation in response to amurensin G. Amurensin G-mediated endothelium-dependent relaxation was blocked by inhibition of AMPK, ER, Src, or PI3K. These results suggest that amurensin G enhances NO production via eNOS phosphorylation in endothelial cells, and ER-dependent AMPK/PI3K pathways are required. Amurensin G would be applicable to prevent atherosclerosis.

Antinociceptive and antiinflammatory effects of Niga-ichigoside F1 and 23-hydroxytormentic acid obtained from Rubus coreanus.

As an attempt to search for bioactive natural constituents exerting antinociceptive and antiinflammatory activities, we examined the potency of the extract of Rubus coreanus fruits by the activity-guided fractionation. The EtOAc- and BuOH fraction and those alkaline hydrolysates showed significant antinociceptive effects as assessed by writhing-, hot plate- and tail flicks tests in mice and rats as well as antiinflammatory effect in rats with carrageenan-induced edema. BuOH extract was subjected to column chromatography to obtain a large amount of niga-ichigoside F(1) (1,23-hydroxytormentic acid 28-O-glc), which was again hydrolyzed in NaOH solution to yield an aglycone 23-hydroxytormentic acid (1a). The aglycone, 23-hydroxytormentic acid, was much more potent in both antinociceptive and antiinflammatory tests than the glycoside, niga-ichigoside F(1). The antiinflammatory effects of these compounds were further supported by the reduction of carrageenan-induced lipid peroxidation and hydroxyl radical in serum. These results suggested that 23-hydroxytormentic acid might be an active moiety of niga-ichigoside F(1) present in R. coreanus.