Experimental model of traumatic ulcer in the cheek mucosa of rats

The effect of biopolymer gel derived from sugarcane on healing of traumatic oral ulcers: an experimental study

PURPOSE

The extracellular polysaccharide (EPS) is produced by the bacterium Zoogloea sp. and plays a positive role in tissue repair. The purpose of this study was to clinically and histologically compare the effects of EPS in the healing of traumatic oral ulcers in rats with the effects of triamcinolone.

METHODS

Ulcers were induced in the oral mucous of 45 male Wistar rats, divided into three groups: control group, treated with triamcinolone, and treated with biopolymer gel. In the clinical evaluation, we considered the weight variation of the animals and the size of the lesion area, at baseline and on treatment days 1, 3 and 7. The histological parameters evaluated were the type and intensity of the inflammatory infiltration, the presence of necrosis and foreign body granuloma and the degree of re-epithelialization of the lesion.

RESULTS

The reduction of the lesion area was greater in the animals treated with EPS, with no difference in the intensity of the inflammatory infiltration between the groups on days 3 and 7 of treatment.

CONCLUSIONS

The results suggest that topical application of EPS in traumatic oral ulcers of rats promotes faster repair than triamcinolone ointment, without increasing the intensity of inflammatory infiltration under the lesion.

Armillariella tabescens polysaccharide treated rats with oral ulcers through modulation of oral microbiota and activation of the Nrf2/HO-1 pathway

We identified Armillariella tabescens polysaccharide (PAT-W), a compound isolated from a Chinese medicinal mushroom, as a potential novel oral ulcer (OU) drug. In treating OU rats with PAT-W, especially in the high-dose group, oral mucous tissue TNF-α, IL-1β, and IL-6 levels were markedly reduced, and pathological morphology and oxidative stress were effectively improved. Western blot analysis showed that the PAT-W channel ameliorated OU mucous tissue damage, which depends on the activation of the Nrf2/HO-1 antioxidant signaling pathway. Furthermore, high-throughput sequencing results showed that PAT-W regulated the maladjustment of the oral microbiota caused by OU. Therefore, based on the new viewpoint of activating the Nrf2/HO-1 pathway and regulating oral microbiota, PAT-W is expected to become a new natural drug for treating oral ulcers and improving patients' quality of life.

An In-Vivo Study of Effects of Platelet-Rich Plasma on Transforming Growth Factor-β1 and Matrix Metalloprotein 9 Expression in Traumatic Ulcers with Diabetes Mellitus

OBJECTIVE

 Diabetes mellitus is not only characterized by alterations in the wound healing process but also during oral ulcer healing. The platelet-rich plasma (PRP) can be used to stimulate the healing process. This study was performed to analyze the effect of PRP on traumatic ulcers with diabetes mellitus in an animal model by analyzing the expression of transforming growth factor β1 (TGF-β1) and matrix metalloprotein 9 (MMP-9).

MATERIALS AND METHODS

 The diabetes mellitus model was developed using streptozotocin that was administrated to Rattus novergicus. The traumatic ulcer model was obtained by placing a heated tip of a ball burnisher for 5 seconds on the lower mucosa labial. Then, the traumatic ulcer was treated with PRP for 3, 5, and 7 days. The expression of TGF-β1 and MMP-9 was analyzed with indirect immunohistochemistry, and differences between each marker were analyzed with statistical analysis.

RESULTS

 All animals showed clinical oral ulceration as a yellow base during the experiment. The application of PRP showed a higher level of TGF-β1 expression than the controls for 3, 5, and 7 days (p < 0.05). In contrast, the MMP-9 expression was lower than the control for 5 and 7 days (p < 0.05).

CONCLUSION

 The PRP affected traumatic ulcers with diabetes mellitus by promoting healing through TGF-β1 expression and suppressing the MMP-9 expression. This material can serve to develop a promising topical therapy for traumatic ulcers, especially with an underlying disease such as diabetes mellitus.

Effect of Nigella sativa Versus Wheat Germ Oil on the Healing of Traumatic Ulcers in Albino Rats

BACKGROUND AND OBJECTIVE

Nigella sativa (NS) oil has been used as an ointment for relief from abscesses, nasal ulcers, orchitis, eczema, and swollen joints. The nutritional and biological values of wheat germ oil (WGO) are imperative points for testing its wound healing properties in traumatic ulcer. The aim of the study was to evaluate and compare the ability of NS versus WGO in promoting the healing of induced traumatic ulcer in albino rats clinically and histologically.

MATERIALS AND METHODS

This study was carried out after the approval of the Research Ethics Committee (REC) of the Faculty of Dentistry, Suez Canal University, in Ismailia, Egypt, on 60 albino rats with induced labial ulcer according to calculated sample size. All animals were anaesthetized with an intraperitoneal injection of 10% ketamine. The ulcer was produced on the labial mucosa corresponding to the midline between the lower two incisors of each rat. After induction of the ulcer, rats were randomly divided into four groups according to the treatment medicament: Group A (negative control group): 15 rats which remained without treatment; Group B (positive control): 15 rats which received daily a topical application of 1 ml of cetylpyridinium chloride (CPC) and lidocaine gel; Group C (NS group): 15 rats which received a daily topical application of 1 mm of NS oil painted by a brush covering the whole area of the ulcer; and Group D (WGO group): 15 rats which received 1 mm of WGO. The ulcers were measured using a digital caliper and were recorded using a digital camera at days 0, 3, 7, and 9, the largest (D) and smallest (d) diameters of the lesion were recorded, and the ulcer area was calculated using the following formula: A=π×D/2×d/2. Tissue samples were taken for histological examination, and the labial mucosa was dissected out and embedded in paraffin wax blocks. The blocks were cut with microtome to obtain sections of 4-5 μm thickness to be stained with hematoxylin and eosin stain and Masson's trichrome stain. All sections were examined under a light microscope, and the presence of inflammatory cells and collagen tissue remodeling were evaluated.

RESULTS

Within the control group, there are statistically non-significant changes in the mean of the surface area of ulcer when comparing changes in 10 rats who survived till the seventh day and inflammatory cell count when comparing changes in five rats who were sacrificed at the seventhday. There was a significant decrease in surface area and inflammatory cell count in five rats who survived till the ninth day. Within the WGO group only, all survived rats had healed ulcer at the ninth day. There is a significant decrease in inflammatory cell count in five rats who survived till the ninth day.

CONCLUSION

WGO was significantly more effective in the treatment of animal-induced ulcer compared to NS oil or CPC and lidocaine oral gel.

Sustainable Treatment of Oral Traumatic Ulcers with Licorice Containing Hydrogels: Integrating Computational Modeling, Quality by Design, Green Synthesis, and Molecular Biological Evaluation

The urge to implement innovative approaches that align with eco-friendly practices and hold promise for enhancing oral health while promoting environmental sustainability has been increasing. This current work aims to develop a sustainable treatment for oral traumatic ulcers using licorice-based hydrogels (LHGs) containing hydroxyethyl cellulose (HEC) as the green gelling agent. Licorice root aqueous extract was phytochemically profiled using UPLC-ESI-MS/MS. Forty-three compounds were detected, with Glycyrrhizic acid being the major component of the extract (34.85 ± 2.77%). By implementing a Quality by Design (QbD) approach, the study investigates the effects of different licorice extract and HEC concentrations on key variables such as pH and viscosity of the prepared formulations, ulcer and wound healing scores, and tissue growth factors via a Full Factorial Experimental Design. The LHGs exhibited desirable consistency, spreadability, and clarity. Statistical analysis, employing an ANOVA test, revealed the high significance of the constructed models with the licorice concentration being the key independent factor affecting all dependent outputs. The pH as well as the viscosity of the prepared LHGs were positively influenced by licorice extract concentration, with higher concentrations leading to increased alkalinity and viscosity. Rheological behavior analysis revealed a pseudoplastic flow with demonstrated thixotropy which is advantageous for application and prolongation of residence time. The wound healing process was assessed through ulcer size, traumatic ulcer healing score (UHS), collagen-1 expression (COL-1), growth factors (EGF, VEGF), pro-inflammatory markers (TNF-α), wound healing score (WHS). LHGs prepared using higher levels of both factors, 30% dried licorice root extract and 4% HEC, demonstrated enhanced wound healing, elevated growth factor expression of 66.67% and 23.24%, respectively, and 88% reduced inflammation compared to the control group, indicating their potential in expediting oral ulcer recovery. Overall, these findings highlight the promising role of green licorice-based hydrogels in promoting sustainable oral mucosal healing.

Evaluation of the healing potential of Nile tilapia skin collagen in traumatic oral ulcers in male rats

OBJECTIVE

To evaluate the healing potential of Nile tilapia skin collagen using a rat model with experimentally induced traumatic oral ulcers.

DESIGN

Male Wistar rats were segregated into three experimental groups (n = 8/group/euthanasia day). Ulcers were induced using a dermatological punch on the left buccal mucosa. The rats were then euthanized on days 1, 5, 10, 15, and 20 (ntotal=120 rats). Each group received topical treatment, 2x/day, with 1 % Nile tilapia skin collagen orabase (experimental group), only orabase (negative control), or Oncilom-A® orabase (positive control). Ulcer area, closure percentage, and body mass variation were measured. Slides were prepared for histological analysis, which included Picrosirius red staining (collagen analysis), and immunohistochemistry (platelet endothelial cell adhesion molecule, alpha-smooth muscle actin, and transforming growth factor-beta).

RESULTS

On day 15, the experimental and positive control groups displayed smaller ulcer areas, a higher percentage of closure, complete re-epithelialization, superior histological repair scores, and a reduced count of polymorphonuclear cells in comparison to the negative control group (p < 0.05). Additionally, the experimental group exhibited an increased number of blood vessels, total collagen (types I and III) and expression of platelet endothelial cell adhesion molecule, alpha-smooth muscle actin, and transforming growth factor-beta relative to the negative and positive control groups (p < 0.05). By day 20, the experimental group showed a more significant weight gain compared to the other groups (p < 0.0001).

CONCLUSIONS

Nile tilapia skin collagen orabase optimizes the healing of traumatic ulcers by stimulating re-epithelialization, angiogenesis, and collagenesis. Transforming growth factor-beta plays a significant role in this process.

Marine collagen peptides: A novel biomaterial for the healing of oral mucosal ulcers

The purpose of this study was to analyze the therapeutic effects of marine collagen peptides (MCPs) from tilapia skin on oral mucosal ulcers in a rat model. CCK-8 and wound healing assays were performed in vitro to evaluate proliferation and migration of L929 cells after treatment with MCPs. The effects of MCPs on the healing of oral mucosal ulcers in a rat model were macroscopically and microscopically analyzed in vivo. Results showed that MCPs promoted proliferation and migration of L929 cells. Moreover, 75%MCPs enhanced the ulcer healing process, suppressed inflammatory response and up-regulated the expression levels of vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF). MCPs are potentially used as a new therapeutic strategy for oral mucosal ulceration.

The Evaluation of Healing Properties of Galium verum-Based Oral Gel in Aphthous Stomatitis in Rats

Although oral ulcers represent one of the most frequent oral mucosal diseases, the available treatment is not sufficient to provide complete ulcer recovery without side-effects. Therefore, the aim of our study was to prepare a mucoadhesive oral gel based on Galium verum ethanol extract (GVL gel) and reveal its healing effects in the model of aphthous stomatitis in rats. Rats with oral ulcers were divided into the following groups: control (untreated), gel base (ulcer was treated with the gel base, three times per day for 10 days), and GVL gel group (the ulcer was treated with GVL gel in the same way as the gel base). Animals from each group were sacrificed on days 0, 3, 6, and 10 for collecting blood and ulcer tissue samples. Healing properties of oral gel were determined by clinical evaluation, as well as biochemical and histopathological examinations. Our findings suggest a significant decrease in the ulcer size in GVL gel group, with healing effects achieved through the alleviation of oxidative stress, reduction in COX-2 immunopositivity, and increase in collagen content in buccal tissue. Significant ulcer repairing potential of GVL gel highlights this oral mucoadhesive gel as a promising tool for prevention and treatment of RAS.

Anti-Inflammatory Activity and Wound Healing Effect of Kaempferia galanga L. Rhizome on the Chemical-Induced Oral Mucosal Ulcer in Wistar Rats

Introduction

Kaempferia galanga L. (K. galanga; local name kencur, Zingiberaceae) is a plant commonly used as a kitchen spice, and empirically it is often used for medicinal purposes. This plant has been shown to have an anti-inflammatory role, but no research has been found on its effect on oral mucosal ulcer. This study aimed to investigate anti-inflammatory activity and wound healing effect of the ethanol extract of K. galanga L. rhizome (EEKG) on the chemical-induced oral mucosal ulcer in Wistar rats.

Methods

In this study, 35 rats were divided into 7 groups (normal, negative, triamcinolone acetonide, and 4 EEKG groups). Acetic acid 70% was used as the oral mucosal ulcer inducer. Parameters observed were macroscopic and microscopic histopathological examinations.

Results

The results revealed that dose of 0.5% of the EEKG was effective in increasing the percent recovery of ulcer area and inflammation sign scores. Meanwhile, doses of 0.5–2% of EEKG were effective in reducing the histopathological score. Interestingly, topical EEKG in our study was more effective compared with triamcinolone acetonide (the conventional therapy for oral mucosal ulceration).

Discussion

The EEKG has been confirmed its anti-inflammatory activity by accelerating the healing process on the chemical-induced oral mucosal ulcer in Wistar rats, based on the percent recovery of the ulcer area, the percent recovery of the inflammation sign score, and the histopathology score.

Conclusion

Taken together, K. galanga L. is very potential to be developed as a prospective phytopharmaceutical for the treatment of oral mucosal ulceration in human after clinical trials.

Fixation of free gingival grafts with cyanoacrylate glues: A histomorphometric and immunohistochemical study

Aim

The objective of this study was to evaluate the inflammatory process resulting from the use of two cyanoacrylate-based adhesives to stabilize grafts.

Methodology

A total of 45 male Wistar rats were randomly divided into three groups (n = 15/group) treated with ethyl cyanoacrylate glue (TG1), octyl-2-cyanoacrylate glue (TG2) or suture threads (CG). After de-epithelialization in the anterior gingival region of the mandible, the graft was removed from the donor site (hard palate), taken to the recipient site and stabilized according to the protocol of each group. After 7, 14, and 45 days, the animals were euthanized. The graft area was analysed macroscopically, histologically, histochemically (Masson trichrome), and immunohistochemically positive cell count for TGF-β, α-SMA, RANKL, OPG, FGF, and IL-10. The Kruskal-Wallis/Dunn test (SPSS 20.0, p < 0.05) was used for analysis.

Results

There was no difference in the clinical parameters among the three groups, but TG1 showed the lowest mononuclear inflammatory cell count and the highest amount of total collagen. FGF immunoexpression was significantly higher for the CG group, but the TG2 showed a significant reduction in the RANKL/OPG ratio.

Conclusion

TG1 had a mild inflammatory response and a higher collagen deposition than other glues, and TG2 had a reduction in the RANKL / OPG ratio.

Anti-inflammatory effect of HGF responses to oral traumatic ulcers using an HGF-Tg mouse model

Hepatocyte growth factor (HGF) has been implicated in inhibiting diverse types of inflammation. Oral traumatic ulceration (OTU) is a common disease of the oral mucosa, and inflammation is the main process for ulcer healing. This study aimed to explore the expression of HGF in oral ulcers and its role in ulcer inflammation. The saliva of 14 recurrent alphous stomatitis (RAS) patients, 18 OTU patients and 17 healthy controls was collected. Traumatic ulcers of the left mucosa were observed in 42 wild-type (WT) and 42 HGF-overexpressing transgenic (HGF-Tg) mice. Histological scores, inflammatory cell expression and serum cytokine expression were measured and analyzed on the 5th day. The HGF protein level in ulcer-affected human saliva was 9.3-fold higher than that in healthy saliva. The HGF protein levels in RAS and OTU saliva were 14- and 5.7-fold higher, respectively, than those in healthy saliva. Traumatic ulcers enhanced HGF expression in ulcer-affected oral mucosa and in the blood of C57BL/6 mice by 1.21- and 1.40-fold, respectively. In HGF-Tg mouse traumatic ulcers, HGF expression was 1.34-fold higher than that in wild-type mice. HGF-Tg mice had lower weight loss, less ulcer area and lower histopathology scores than WT mice. The results from immunohistochemistry, flow cytometry and serum cytokine analysis showed that HGF-Tg animals presented fewer Ly6G-positive neutrophils and higher levels of circulating inflammatory cytokines. HGF overexpression alleviated weight loss, ulcer area and inflammation, suggesting the role of HGF in promoting the healing of oral ulcers.

Evaluation of clinical, histology, TNF-α, and collagen expressions on oral ulcer in rats after treatment with areca nut and chrysanthemum oral gel

Background: Areca nut (Areca catechu Linn.) is the seed of the fruit of the oriental palm that is commonly used among Southeast Asian communities. Chrysanthemum (Dendrathema grandiflora) is a flowering plant originating from East Asia and dominantly grows in China. Both of these plants have strong antioxidant activities. To investigate the mechanism of their wound healing activities, we prepared areca nut and chrysanthemum polyethylene oral gel and performed several in vivo assays using Sprague–Dawley rats. Methods: Sprague–Dawley rats were divided into five groups: Negative control group (rats with base gel treatment), positive control group (rats treated with triamcinolone acetonide), F1 (treatment with 20% areca nut:80% chrysanthemum), F2 (treatment with 50% areca nut:50% chrysanthemum), and F3 (treatment with 80% areca nut:20% chrysanthemum). Traumatic ulcers were performed on the buccal mucosa of all experimental animals that received topical oral gel and triamcinolone acetonide twice a day for seven days. The clinical and histological characteristics were analyzed and scored. Results: During the six days, the ulcerated area receded linearly over time and was completely cicatrized in F2 and positive control group (Dependent t-test, p<0.05). There were significant increases in body weight in F2 and positive control groups. There were no significant differences between groups in histology examination (Kruskal Wallis test, p<0.05). The moderate score of TNF-α levels was seen in F2 and positive control groups (ANOVA/Tukey test). Similar results were seen in the collagenases assay. Conclusions: A balanced combination of areca nut and chrysanthemum extract in the oral gel can optimize the healing of traumatic oral ulcers in rats through the increase of TNF-α and collagen deposition.

A proline derivative-enriched methanol fraction from Sideroxylon obtusifolium leaves (MFSOL) stimulates human keratinocyte cells and exerts a healing effect in a burn wound model

It was previously demonstrated that the methanol fraction of Sideroxylon obtusifolium (MFSOL) promoted anti-inflammatory and healing activity in excisional wounds. Thus, the present work investigated the healing effects of MFSOL on human keratinocyte cells (HaCaT) and experimental burn model injuries. HaCaT cells were used to study MFSOL's effect on cell migration and proliferation rates. Female Swiss mice were subjected to a second-degree superficial burn protocol and divided into four treatment groups: Vehicle, 1.0% silver sulfadiazine, and 0.5 or 1.0% MFSOL Cream (CrMFSOL). Samples were collected to quantify the inflammatory mediators, and histological analyses were performed after 3, 7, and 14 days. The results showed that MFSOL (50 μg/mL) stimulated HaCaT cells by increasing proliferation and migration rates. Moreover, 0.5% CrMFSOL attenuated myeloperoxidase (MPO) activity and also stimulated the release of interleukin (IL)-1β and IL-10 after 3 days of treatment. CrMFSOL (0.5%) also enhanced wound contraction, promoted improvement of tissue remodeling, and increased collagen production after 7 days and VEGF release after 14 days. Therefore, MFSOL stimulated human keratinocyte (HaCaT) cells and improved wound healing via modulation of inflammatory mediators of burn injuries.

The effect of indocyanine green-mediated photodynamic therapy in healing of experimentally induced oral mucosal traumatic ulcer in rat

Photodynamic therapy (PDT) is a promising approach for the healing of ulcerative lesions. This study aimed to investigate the effect of PDT using indocyanine green (ICG) in the healing of the experimentally induced oral mucosal traumatic ulcer in rat. Sixty adult male Sprague-Dawley rats were recruited in this experimental study. The ulceration was surgically made in the left cheek mucosa, and the rats were randomly assigned into four equal groups (n = 15). Oral ulcers in groups 1 and 2 were treated with the sterile saline solution (0.9%) and ICG (1 mg/ml). In group 3, laser irradiation was applied using the 810 nm diode laser in the continuous-wave mode for 30 s (light dose: 55 J/cm2, power: 300 mW, spot size: 4.5 mm). Following the topical application of ICG (1 mg/ml) in group 4, laser irradiation was performed in the same way as the previous group. After 24 h, treatments were repeated once more in all groups. The healing process was histopathologically assessed at the 3rd, 7th, and 14th days after ulceration. Wound healing was significantly accelerated in the ICG-mediated PDT group in comparison to the control group at all sampling time points (p < 0.005). However, the other groups displayed a similar healing rate (p > 0.05). Data suggest that ICG-mediated PDT has the potential to accelerate wound healing and prevent clinical infection in oral mucosal traumatic ulcers. However, further studies are required to confirm whether our results can be generalized to other wounds.

Photodynamic antimicrobial chemotherapy using indocyanine green in experimentally induced intraoral ulcers in rats

BACKGROUND

Photodynamic antimicrobial chemotherapy (PACT) is a promising modality for eradication of microorganisms from the wound. This study aimed to investigate the effectiveness of PACT using indocyanine green (ICG) for reduction of bacterial load of oral ulcers in rats and its impact on the healing process.

METHODS

In this experimental study, 50 adult male Sprague Dawley rats were recruited. Oral ulcers were surgically made on the left cheek mucosa, and animals were randomly assigned into five groups (n = 10). Wound site in groups 1, 2, and 3 was irrigated with the sterile saline (0.9%), chlorhexidine (CHX; 0.2%), and ICG solutions (1 mg/mL), respectively. Group 4 was exposed to laser irradiation using 810 nm diode laser on continuous-wave mode for 30 seconds (fluence: 55 J/cm² , power: 300 mW, spot size: 4.5 mm). In group 5, PACT was performed using topical application of ICG followed by laser irradiation in the same way as the previous group. Bacterial load of oral ulcers was assessed before and after each treatment modality. Besides, rats were sacrificed on the 5th day post ulceration and histological features of healing were evaluated.

RESULTS

Bacterial load was significantly reduced merely in the PACT-ICG-treated group by one log (P < .0001). Animals in the PACT-ICG-treated group also showed an accelerated healing in comparison with others on the 5th day of an experiment.

CONCLUSION

Photodynamic antimicrobial chemotherapy using topical application of ICG has a potential to reduce the bacterial load of oral ulcers and accelerate wound repair. Therefore, it can be considered as an alternative to currently available modalities for wound management.

Effect of ozone therapy on wound healing in the buccal mucosa of rats

OBJECTIVE

The objective of this study was to evaluate the effects of ozone therapy on wound healing formed experimentally in the oral cavity of rats.

DESIGN

Two surgical wounds were generated on the cheeks of 24 Wistar rats, bilaterally. Half of the animals were submitted to ozone therapy on both wounds (experimental group) and the other half received no treatment (control group). In the experimental group, wounds were exposed to ozone gas 1, 2 or 3 (60 μg/mL) times. Evaluation of wound healing of the buccal mucosa was followed for 1, 3 and 7 days. The distribution of neutrophils, fibroplasia and angiogenesis were analyzed. Samples were classified in a healing numerical scale according to the inflammatory intensity. Data were submitted to Mann-Whitney and Kruskal-Wallis tests (α = 0.05).

RESULTS

On day 1, wounds were similar in both groups, lesions were open and bloody with slightly minor bleeding in the ozone therapy group. On day 3, the group with ozone therapy was almost all refurbished and with higher angiogenesis, while the control group still had more bloody points and lower blood vessels. On day 7, both wounds were remodeled, with higher fibroplasia in the group that received ozone therapy.

CONCLUSION

It can be concluded that ozone therapy was effective in improving angiogenesis and fibroblasts count in the buccal mucosa of rats.

Transoral Low-Level Laser Therapy Via a Cylindrical Device to Treat Oral Ulcers in a Rodent Model

BACKGROUND AND OBJECTIVE

Various clinical and animal studies have applied low-level laser therapy (LLLT) to treat oral ulcers. However, most previous studies applied lasers with small pinpoint irradiation, which required multiple laser irradiations to cover the complete extent of the ulcer. The objective of this study was to evaluate the effect of LLLT using a 635 nm diode laser via a transoral device to cover the whole lesion on oral ulcers in an animal model.

STUDY DESIGN/MATERIALS AND METHODS

An animal model of oral ulcers was developed with a 6 mm skin punch in the right buccal mucosa of Wistar rats (males, body weight 200-250 g). Three days after the mucosal injury, LLLT (spot size 2 cm² ) was conducted once a day for 5 days. Twenty-eight rats were randomly assigned into four groups according to energy density (control group, 5, 20, 75 J/cm² ). The size of the ulcers was measured and histologic analysis were performed ten days after the initial mucosal injury.

RESULTS

The mean size of the oral ulcers was significantly smaller in rats treated with an energy density of 20 J/cm² than that of any other group (control group or energy densities of 5 or 75 J/cm² ). The irradiation of oral ulcers with an energy density of 20 J/cm² accelerated the oral mucosa wound healing process and decreased inflammation and granulation tissue, resulting in good reepithelization. However, the histologic outcomes of rats irradiated with energy densities of 5 or 75 J/cm² were comparable with those of the control group.

CONCLUSION

LLLT using a 635 nm diode laser for oral ulcers with a transoral cylindrical device for wide light distribution may accelerate the wound healing process. LLLT with large-surface irradiation may be a substitute for previous LLLT for oral mucosal lesions conducted in a punctuate manner. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

Topical Niosome Gel Containing an Anthocyanin Complex: a Potential Oral Wound Healing in Rats

Anthocyanins from dietary sources showing potential benefits as anti-inflammatory in oral lesions were developed as an anthocyanin complex (AC), comprised of extracts of Zea mays (CC) and Clitoria ternatea (CT), and formulated into a niosome gel to prove its topical oral wound healing in vitro and in vivo investigations. The AC formed nano-sized clusters of crystalline-like aggregates, occurring through both intra- and inter-molecular interactions, resulting in delivery depots of anthocyanins, following encapsulation in niosomes and incorporation into a mucoadhesive gel. In vitro permeation of anthocyanins was improved by complexation and further enhanced by encapsulation in niosomes. Collagen production in human gingival fibroblasts was promoted by AC and AC niosomes, but not CC or CT. The in vivo wound healing properties of AC gel (1 and 10%), AC niosome gel (1 and 10%), fluocinolone acetonide gel, and placebo gel were investigated for incisional wounds in the buccal cavities of Wistar rats. AC gel and AC niosome gel both reduced wound sizes after 3 days. AC niosome gel (10%) gave the highest reduction in wound sizes after day 3 (compared to fluocinolone acetonide gel, p < 0.05), and resulted in 100% wound healing by day 5. Histological observations of cross-sectioned wound tissues revealed the adverse effects of fluocinolone gel and wound healing potential of AC niosome gel. Topical application of AC niosome gel exhibited an anti-inflammatory effect and promoted oral wound closure in rats, possibly due to the improved mucosal permeability and presence of delivery depots of AC in the niosome gel.

Experimental model of oral ulcer in mice: Comparing wound healing in three immunologically distinct animal lines

Background:

The oral wound healing is dependent of immune participation and the absence or augment of one specific immune profile can delayed wound healing.

Objectives:

So, the objective of this study was t evaluate the wound healing of oral traumatic ulcer (OTU) in cheek mucosa of swiss, balb/c and c57bl6J mice.

Materials and Methods:

A total of 144 mice (25-30g) were distributed in three groups: swiss (n = 48), balb/c (n = 48) and c57bl/6j (n = 48). An OTU was performed using a dermatological punch in left cheek mucosa. The animals were euthanized daily (n = 6/group/day by 8 days) for evaluation of the ulcer area, weight loss and histological analysis.

Results:

There are no differences between ulcer area in three groups; however only swiss group showed total wound healing. Swiss group showed weight loss in 2^nd and 3^rd days recovering the body mass in 4^th day (P < 0.01). Balb/c group showed the greater weight loss (P < 0.05) and c57bl/6j did not show body mass variation (P = 0.258). Histologically swiss group was the only group that showed total reepithelization (P < 0.001). Balb/c (P = 0.022) and c57bl/6j (P < 0.001) showed decrease in histological scores, chronic inflammation on the 8^th day. Actinomyces was significantly more observed in surface of OTU of balb/c.

Conclusion:

Balb/c mice showed high infection of OTU surface delaying wound healing, and greater weight loss. C57bl/6J mice showed low infection of OTU, but not healing along the eight days. Only the Swiss mice showed wound healing of OTU.

The effects of freeze-dried Ganoderma lucidum mycelia on a recurrent oral ulceration rat model

Background

Conventional scientific studies had supported the use of polysaccharides and β-glucans from a number of fungi, including Ganoderma lucidum for the treatment of recurrent oral ulceration (ROU). Our aim of the present study was to evaluate whether freeze-dried powder from G. lucidum mycelia (FDPGLM) prevents ROU in rats.

Methods

A Sprague-Dawley (SD) rat model with ROU was established by autoantigen injection. The ROU rats were treated with three different dosages of FDPGLM and prednisone acetate (PA), and their effects were evaluated according to the clinical therapeutic evaluation indices of ROU.

Results

High-dose FDPGLM induced significantly prolonged total intervals and a reduction in the number of ulcers and ulcer areas, thereby indicating that the treatment was effective in preventing ROU. Enzyme-linked immunosorbent assay (ELISA) showed that high-dose FDPGLM significantly enhanced the serum transforming growth factor-β1 (TGF-β1) levels, whereas reduced those of interleukin-6 (IL-6) and interleukin-17 (IL-17). Flow cytometry (FCM) showed that the proportion of CD4⁺ CD25⁺ Foxp3⁺ (forkhead box P3) regulatory T cells (Tregs) significantly increased by 1.5-fold in the high-dose FDPGLM group compared to that in the rat model group (P < 0.01). The application of middle- and high-dose FDPGLM also resulted in the upregulation of Foxp3 and downregulation of retinoid-related orphan receptor gamma t(RORγt) mRNA.

Conclusion

High-dose FDPGLM possibly plays a role in ROU by promoting CD4⁺ CD25⁺ Foxp3⁺ Treg and inhibiting T helper cell 17 differentiation. This study also shows that FDPGLM may be potentially used as a complementary and alternative medicine treatment scheme for ROU.

Electronic supplementary material

The online version of this article (10.1186/s12906-017-2021-8) contains supplementary material, which is available to authorized users.

Ketoprofen-loaded Eudragit electrospun nanofibers for the treatment of oral mucositis

Purpose

The purpose of this study was to formulate ketoprofen (KET)-loaded Eudragit L and Eudragit S nanofibers (NFs) by the electrospinning technique for buccal administration to treat oral mucositis as a safe alternative to orally administered KET, which causes gastrointestinal tract (GIT) side effects.

Materials and methods

NFs were prepared by electrospinning using Eudragit L and Eudragit S. Several variables were evaluated to optimize NF formulation, such as polymer types and concentrations, applied voltage, flow rate and drug concentrations. Differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) and analyses of drug contents, hydration capacity, surface pH, drug release and ex vivo permeation were performed to evaluate the NFs. The selected formulation (F1) was evaluated in vivo on induced oral mucositis in rabbits.

Results

SEM revealed that 20% polymer formed smooth and bead-free NFs. DSC results confirmed the amorphous nature of KET in the NFs. FTIR confirmed hydrogen bond formation between the drug and polymer, which stabilized the NFs. Both formulations (F1 and F2) had an acceptable surface pH. The drug loading was >90%. The amount of KET released from NF formulations was statistically significantly higher (P≤0.001) than that released from the corresponding solvent-casted films. The complete release of KET from F1 occurred within 2 hours. Ex vivo permeation study revealed that only a small fraction of drug permeated from F1, which was a better candidate than F2 for local buccal delivery. In vivo evaluation of F1 on oral mucositis induced in rabbits demonstrated that F1 reduced the clinical severity of mucositis in rabbits under the current experimental conditions. The attenuated clinical severity was accompanied by a marked reduction in inflammatory infiltrate and re-epithelization of the epithelial layer.

Conclusion

Eudragit L100 nanofibers (EL-NF) loaded with KET (F1) suppressed the inflammatory response associated with mucositis, which confirmed the efficacy of local buccal delivery of KET-loaded EL-NF in treating oral mucositis.

Modulator effect of a polysaccharide-rich extract from Caesalpinia ferrea stem barks in rat cutaneous wound healing: Role of TNF-α, IL-1β, NO, TGF-β

ETHNOPHARMACOLOGICAL RELEVANCE

In folk medicine stem barks of Caesalpinia ferrea (Caesalpinioideae) are used to treat enterocolitis, rheumatism and wounds and in experimental procedures, its aqueous extracts demonstrated antiulcer, anti-inflammatory, analgesic, and healing effects.

AIM OF THE STUDY

The healing mechanism of the polyssacharide-rich extract of C. ferrea stem barks (TPL-Cf) was investigated in a model of excisional cutaneous wound in Wistar rats.

MATERIALS AND METHODS

Excisional wounds received topical treatment with TPL-Cf (0.025-0.1%) during 21 days. Hypernociception, macroscopical, histological and immunohistochemical parameters were evaluated and analyzed by ANOVA, Bonferroni and Kruskal-Wallis tests, followed by Dunn and Chi-Square tests.

RESULTS

TPL-Cf (0.1%) reduced wound area and hypernociception, and increased wound contraction. TPL-Cf reduced leukocyte infiltration and vascular permeability, and stimulated fibroblasia, angiogenesis, well formed granulation tissue, collagen deposition and epithelial layer formation. TPL-Cf reduced TNF-α expression and the levels of PGE2 (73%-day 5), IL-1 (42%-day 2), MDA (38%-day 5), total protein (53%-day 2; 73%-day 5) and MPO activity (53%-day 2), but increased the expression of i-NOS (days 5 and 7), TGF-β (day 5) and the levels of NO (3.6 fold-day 5).

CONCLUSION

The polysaccharide-rich extract of C. ferra stem barks accelerates wound healing by the control of the inflammatory phase and attenuates hypernociception via modulation of inflammatory mediators (TNF-α, IL-1β, NO, TGF-β).

TNF-alpha expression, evaluation of collagen, and TUNEL of Matricaria recutita L. extract and triamcinolone on oral ulcer in diabetic rats

OBJECTIVE

to evaluate the influence of Tumor Necrosis Factor alpha (TNF-α) and apoptosis in rats with DM treated with chamomile extract or triamcinolone.

MATERIAL AND METHODS

Wistar male rats (210.0±4.2 g) were divided into five groups: negative control group (NCG) without diabetes; positive control group (PCG) with DM (alloxan, 45 mg/kg); and groups treated with chamomile extract (normoglycemic= NCG group and diabetic= DCG group) and with triamcinolone (TG). Traumatic ulcers were performed on all animals that received topical triamcinolone, chamomile extract or saline 12/12 hours for ten days.

RESULTS

On days five and ten the animals were euthanized and the ulcers were analyzed by light microscopy, TUNEL assay, and immunohistochemically (TNF-α). The NCG (p=0.0062), PCG (p=0.0285), NCG (p=0.0041), and DCG (p<0.0001) groups were completely healed on the 10th day, however, there was no healing on the TG (p=0.5127) group. The TNF-α expression showed a significant reduction from the 5th to the 10th day in NCG (p=0.0266) and DCG (p=0.0062). In connective tissue, the TUNEL assay showed a significant reduction in the number of positive cells in NCG (p=0.0273) and CNG (p=0.0469) and in the epithelium only in CDG (p=0.0320).

CONCLUSIONS

Chamomile extract can optimize the healing of traumatic oral ulcers in diabetic rats through the reduction of apoptosis in the epithelium and TNF-α expression.

Effect of laser (λ 660 nm) and LED (λ 630 nm) photobiomodulation on formocresol-induced oral ulcers: a clinical and histological study on rodents

The aim of this study was to evaluate, clinically and histologically, the influence of laser and LED photobiomodulation in the healing of formocresol-induced oral mucosa ulcers of rats. We used 60 Wistar rats in which oral ulcers were induced on the gingiva of the lower incisors. Forty-eight hours after inducing the ulcers, the animals were divided into three groups: laser, LED, and untreated. Animals from the laser group received irradiation with GaAlAs, 660 nm, CW, 40 mW, φ 4 mm(2), 4.8 J/cm(2). Animals from the LED group received irradiation with InGaAIP, 630 nm, 150 mW, 4.8 J/cm(2), 0.8 cm spot. Forty-eight hours after oral ulcer induction, both irradiations were applied in a punctuate manner in the center of the ulcer at 48-h interval until the end of the experimental period. The animals were killed at 3, 5, 7, and 11 days after day 0. The results of the clinical evaluation showed that the laser and LED phototherapies were able to accelerate the healing of formocresol-induced oral ulcers, which occurred first in the laser group (ANOVA, p < 0.05). Histologically, there was a slight variation between LED and laser therapy; therefore, the laser group proved to be effective in accelerating wound healing, especially at 5 days, whereas the LED group was more effective at the end of the experimental period. It was concluded that laser and LED photobiomodulation were effective in accelerating the healing of formocresol-induced oral ulcers in both clinical and histological aspects.

Topical treatment of the buccal mucosa and wounded skin in rats with a triamcinolone acetonide-loaded hydrogel prepared using an electron beam

In this study, a triamcinolone acetonide-loaded hydrogel was prepared by electron beam irradiation and evaluated for use as a buccal mucoadhesive drug delivery system. A poloxamer was modified to have vinyl end groups for preparation of the hydrogel via an irradiation cross-linking reaction. Carbopol was introduced to improve the mucoadhesive properties of the hydrogel. The in vitro release of triamcinolone acetonide from the hydrogel was examined at 37 °C. To investigate the topical therapeutic effect of triamcinolone acetonide on wounded rat skin and buccal mucosa, the appearance and histological changes were evaluated for 15 days after treatment with saline, triamcinolone acetonide solution, triamcinolone acetonide hydrogel, and blank hydrogel, respectively. Triamcinolone acetonide was released constantly from the gel formulation at 37 °C and reach 100% at about 48 h. After 15 days, in the skin of the group treated with the triamcinolone acetonide-loaded hydrogel, the wound was almost completely free of crust and a number of skin appendages, including hair follicles, had formed at the margins of the tissue. Moreover, the inflammatory response in the buccal mucosa was milder than that in the other groups, and the wound surface was completely covered with regenerating, hyperkeratotic, thickened epithelial cells. Our results indicate that the triamcinolone-acetonide hydrogel showed sustained drug release behavior, while causing no significant histopathological changes in buccal and skin tissues. Therefore, this hydrogel system may be a powerful means of drug delivery for buccal administration with controlled release and no tissue irritation.