Wound healing of nasal mucosa in a rat

Modified chitosan: Insight on biomedical and industrial applications

Chitosan (CS), a by -product of chitin deacetylation can be useful in a broad range of purposes, to mention agriculture, pharmaceuticals, material science, food and nutrition, biotechnology and of recent, in gene therapy. Chitosan is a highly desired biomolecule due to the existence of many sensitive functional groups inside the molecule and also because of its net cationicity. The latter provides flexibility for creating a wide range of derivatives for particular end users across various industries. This overview aims to compile some of the most recent research on the bio-related applications that chitosan and its derivatives can be used for. However, chitosan's reactive functional groups are amendable to chemical reaction. Modifying the material to show enhanced solubility, a greater range of application options and pH-sensitive targeting and others have been a major focus of chitosan research. This review describes the modifications of chitosan that have been made to improve its water solubility, pH sensitivity, and capacity to target chitosan derivatives. Applying the by-products of chitosan as antibacterial, in targeting, extended release and as delivery systems is also covered. The by-products of chitosan will be important and potentially useful in developing new biomedical drugs in time to come.

Effects of submucoperichondrial application of platelet-rich plasma on nasal mucosal healing after septoplasty

OBJECTIVE(S)

Our aim is to investigate the effects of the submucoperichondrial application of Platelet Rich Plasma (PRP) on nasal mucosal healing after septoplasty surgery.

METHOD(S)

This prospective randomized observational study was conducted between July 2019 and February 2021, with 40 patients aged 18-60 years who underwent closed the only septoplasty operation for similar septal deviations. Patient divided into two group; 21 patients were placed in PRP group to which PRP was applied on all mucosal surface and submucoperichondrial area of septum and 19 patients were placed in control group to which saline solution was applied on same regions. Nasal obstruction score, mucociliary clearance time, presence of nasal crusting, and bleeding time were evaluated on 5th, 10th, 15th day after surgery and compared between groups.

RESULTS

Intranasal crusting on day 10 was found to be lower in the PRP group (n:13 68.4 %) than control group (n:7 33.3 %) with a statistically significant difference (p = 0.028). The nasal obstruction score on day 10 and 15 were found to be lower in the PRP group (3,33 ± 2,75, 2,07 ± 2,20) (than the control group (5,44 ± 2,26, 3,37 ± 1,92) with a statistically significant difference (p = 0,003,p = 0,009). The mucociliary clearance rate was found to be higher and the bleeding time was found to be lower in the PRP group, but a statistically significant difference was not observed.

CONCLUSIONS

Application of submucoperichondrial PRP could have beneficial effects on nasal mucosal repair, nasal crusting, and congestion after septoplasty surgery.

The Effect of Rosmarinic Acid on Wound Healing of Nasal Mucosa in the Rats

BACKGROUND

The nose can be damaged by environmental pollutants and foreign bodies, as well as a result of trauma, infection or surgical interventions. Proper healing of the damaged nasal mucosa is important for health.

OBJECTIVE

There is no study in the literature investigating the effects of rosmarinic acid on mucosal healing. The aim of this study was to investigate the effect of rosmarinic acid on nasal mucosal healing.

METHODS

21 male, adult Spraque Dawley albino rats were divided into three groups as the control group, the local treatment group in which rosmarinic acid was applied locally to the nasal mucosa, and the systemic treatment group in which rosmarinic acid was injected intraperitoneally. The wound area was obtained by creating a trauma area by inserting a 10 mm interdental brush through the right nasal nostril into the right nasal cavities of all animals. For the following 15 days, the treatment agent was applied as indicated once a day and on the 15th day the animals were decapitated and tissue samples taken from the nasal mucosa were prepared for histopathological examination. The preparations were examined in terms of cellular hyperplasia, goblet cell hypertrophy and degeneration, leukocyte infiltration, cilia loss and degeneration, edema and vascular dilatation, and they have been classified into four categories as mild (+), moderate (++), severe (+++) and very severe (++++).

RESULTS

There was a significant difference between the groups in terms of all parameters evaluated, and there is a decrease in the intensity of the parameters with transition from the control group to the local group and from there to the systemic group.

CONCLUSION

Systemic rosmarinic acid administration showed an enhancing effect on the healing of experimentally induced nasal mucosal injury due to its possible anti-inflammatory effect.

Effect of Locally Administered Estradiol on Wound Healing in a Nasal Septal Perforation Animal Model

We aimed to investigate the effect of estradiol on wound healing in an experimental nasal septal perforation (NSP) model created in rats. Twenty-two Sprague Dawley healthy male rats were separated into two groups. NSP, approximately 2 mm in diameter, was created in each animal. The 0.1 mL 0.12% estradiol (12 g/L) (study group) and 0.1 mL 0.9% saline (9 g/L) (control group) were applied topically once a day for 14 days. The rats were sacrificed on the 14th day and the cartilage nasal septum of each animal was excised for histopathological examination. The nasal mucosal epithelial regeneration and degeneration, acute inflammatory cell count, fibroblast number, vascularization, granulation tissue formation, giant cell number, eosinophil number, degeneration and regeneration of the nasal cartilage, and collagen density were examined. The macroscopic closure rate of the perforations and histopathological parameters were evaluated statistically. In this study, the epithelial regeneration, the fibroblast count, the granulation tissue formation, and the amount of collagen were significantly higher in the study group than in the saline group (p < 0.05). The acute inflammatory activity was lower in the estradiol group than in the saline group (p < 0.05). There was no statistically significant difference in the closure rate of perforation between the two groups (p = 0.163). No significant difference was found in other comparisons (p > 0.05). The locally administered estradiol may improve wound healing of the nasal septum in an experimental NSP animal model. LEVEL OF EVIDENCE:  Not applicable.

Nasal Packing Materials and Placement Duration on Wound Healing in Nasal Mucosa: An Animal Study

OBJECTIVE

The histological findings of wound healing depending on different nasal packing materials and replacement periods were lacking.

METHODS

Mucosal defects were created in the nasal septum of rabbits and covered with Spongel®, Algoderm®, or Nasopore®, which were cleaned on Day 14. To investigate the effect of replacement durations, Spongel® was removed on Days 3 and 7. All nasal septal specimens were collected on Day 28. Samples without packing material were prepared as controls. Depending on residual packing materials in the regenerated tissue, specimens were classified into the remnant and non-remnant groups, and morphology was compared using epithelium grade score and subepithelial thickness.

RESULTS

The epithelium grade score in the Spongel-14d group was lower than that in the other groups (p < 0.05). Subepithelial thickness was higher in the Algoderm-14d and Spongel-14d groups (p < 0.05). Epithelium grade scores were higher and subepithelial thicknesses were lower in the Spongel-3d and -7d groups than in the Spongel-14d group. Epithelium grade score was lower and subepithelial thickness was higher in the remnant group (n = 10) than in the non-remnant group (n = 15; p < 0.05).

CONCLUSIONS

Differences in packing materials and placement durations affected wound healing of nasal mucosa. The selection of appropriate packing materials and replacement duration was considered essential for ideal wound healing.

LEVEL OF EVIDENCE

NA Laryngoscope, 134:562-568, 2024.

Topical Intranasal Insulin Enhances Healing of Nasal Mucosa: An Experimental Animal Study

OBJECTIVE

Aim of this study was to evaluate the effect of topical intranasal insulin on healing of nasal mucosa in a rat model.

METHODS

Forty-eight Wistar rats, weighing between 250 and 300 g and aged 10-12 weeks were used and randomized into two equal groups. 1.9 mm curette was introduced through the left nostril and 1.9 mm mucosa from the left nasal septum was curetted. Postoperatively, animals in the control group received 1 mL of physiologic saline, 3 times a day in a nasal irrigation fashion. Animals in the experimental group received 1 mL of 5 IU/mL regular insulin in saline solution. Subjects were sacrificed after 5, 10, and 15 days and macroscopic and histomorphometric evaluations were performed.

RESULTS

There were no mucosal synechiae and septal perforation macroscopically. Histological examination revealed that the defect size reduction was 21% in the saline group versus 56% in the insulin group on the fifth day (p = 0.006). There was 62% defect reduction in the saline group versus 79% in the insulin group on the 10th day (p = 0.034). On the 15th day, only 67% of saline group animals had complete defect closure, whereas 100% of animals treated with insulin had complete closure (92% vs 100% mucosal defect reduction, p = 0.036). Both edema and inflammation were less in the insulin group on 15th day (p = 0.006; p = 0.023, respectively).

CONCLUSION

The results from this study support the safety and efficacy of topical insulin on wound healing in the literature. This study could guide further experimental studies that examine human sinonasal wound healing.

The Effect of Melatonin on Nasal Septal Wound Healing in an Experimental Animal Model

The purpose of our study was to examine the effect of melatonin (MLT) on wound healing in the nasal septum. Twenty-two Sprague-Dawley rats of the male sex were included in this experimental study. Nasal septal perforation (NSP), about 2 mm in diameter, was formed in each rat. MLT was applied topically to the subjects in the study group and saline was applied topically to the subjects in the control group once a day for 14 days. On day 14, the rats were sacrificed and the nasal septums of the subjects were resected for pathological evaluation. In the NSP area, degeneration and regeneration of nasal septal epithelium; degeneration and regeneration of the septal cartilage; number of cells involved in wound healing such as acute inflammatory cells (leukocytes), fibroblast, eosinophil, and giant cell; capillary vessel intensity; granulation tissue formation; and collagen intensity parameters were evaluated histopathologically. The macroscopic size and histopathologic examination results of NSPs were statistically analyzed. In the MLT group, the epithelium regeneration, cartilage regeneration, fibroblast number, collagen density, vascularity, and granulation formation were significantly higher, and the epithelial degeneration and acute inflammatory cells density were significantly lower, in the NSP area (p < 0.05). In addition, macroscopic healing was significantly higher in the MLT group (p = 0.044 and <0.05). Local application of MLT accelerates nasal septal wound healing. With this feature, the usage of MLT can be promising to prevent the formation of NSP.

Effect of Silver Nitrate Application on the Success of Endoscopic Dacryocystorhinostomy

OBJECTIVES

To compare the clinical outcomes of patients undergoing additional procedures in endoscopic endonasal dacryocystorhinostomy (End-DCR) surgery and discuss the factors affecting the success of End-DCR surgery in light of relevant literature.

METHODS

The study included 155 patients who underwent End-DCR surgery in our clinic due to epiphora. This was a prospective randomized, single-blind, controlled trial. Group I (control) included 54 patients who did not undergo silicone stent insertion or silver nitrate application, group II included 51 patients who underwent silicone stent insertion only, and group III included 50 patients who underwent silver nitrate application only. Statistical analysis was performed on follow-up data regarding anatomic and functional success rates.

RESULTS

Revision surgery was performed in 16 patients who developed persistent epiphora in the postoperative period, including 6 in group I, 7 in group II, and 3 in group III (P = .4). The most common reason for revision surgery was stenosis of the neo-ostium (n = 8), followed by granulation tissue formation (n = 5) and synechia formation (n = 3). Granuloma formation was the most common postoperative complication, and a significant difference was found among the groups with regard to granuloma formation (P = .04). At postoperative month 12, the functional success rate was estimated to be 88%, 86%, and 94%, and the anatomic success rate was estimated to be 94%, 92%, and 96% in groups I, II, and III, respectively, with no significant difference, found among the 3 groups with regard to both rates (P = .79 and P = .76, respectively).

CONCLUSION

The results indicated that stenting and silver nitrate application did not affect surgical success. Our preliminary results on silver nitrate cauterization showed that it is an effective, inexpensive, and practical method to reduce granulation formation in the postoperative period.

Consensus on Methodology for Experimental Studies of Nasal Mucosal Injury

OBJECTIVES

The way wounds heal involves significant complexity, resulting in restoration of functional and anatomical integrity to tissues damaged as a result of trauma (whether mechanical, chemical, or radiation-induced). The authors reviewed the consensus on methodology for experimental studies of nasal mucosal injury.

METHODS

The review aims to find where consensus exists amongst different experimental studies in nasal wound healing about the use of animal models. To achieve this, the authors queried the Pubmed, Proquest Central and Google databases for the last 20 years (i.e. 1996-2016). The search terms were: "mucosa injury," "nasal mucosa injury," "injury," "wound healing," "nasal," "nasal wound healing," "experimental," "animal," "model," "rat," "rabbit," "guinea pig," and "mice." These terms were searched for whether they occurred singly or in combination. The search uncovered 18 papers, on the basis of which this review has been prepared.

RESULTS

The choice of an appropriate animal model is key in investigating nasal mucosal injury. Suitable animals include rodents such as rats or guinea pigs. There are reports in the literature concerning mechanical injury in rat nasal mucosae without attempts to treat it. Mechanical injury was induced unilaterally by means of an interdental brush. Other techniques involved the use of distilled water or irradiating the tissue to induce trauma.

CONCLUSION

In this review, the use of a rat, guinea pig or rabbit model for human nasal mucosal injury is reviewed. Such models are suitable for use in well-designed experimental studies.

Pathological Features of Free Graft and Pedicled Flap in the Nasal Cavity: An Animal Study

OBJECTIVES/HYPOTHESIS

Recent developments in reconstructive techniques for mucosal defects using mucoperiosteal materials have enabled rapid recovery of physiological function after endoscopic sinus surgery. Clinical trials have described the advantages, disadvantages, and different outcomes of free graft and pedicled flap, which, respectively, sacrifice or preserve blood flow. However, histological changes, that affect the postoperative outcomes after reconstruction, remain unclear. We created an animal model for the reconstruction of mucosal defects using free grafts and pedicled flaps, and evaluated them histologically.

STUDY DESIGN

Animal study.

METHODS

We created mucosal defects in the left nasal septum of 20 rabbits and performed reconstruction with free grafts and pedicled flaps. The distribution of ciliary and goblet cells at the reconstruction site was evaluated after 7 and 28 days using hematoxylin and eosin-stained sections to calculate the Ciliary Cell Index and Goblet Cell Index. The severity of inflammation was assessed using the Cartilage Inflammatory Cell Score.

RESULTS

Crusting and changes in the mucosal morphology at the reconstruction site occurred only in the free graft group. In addition, the pedicled flap group had significantly greater preservation of ciliary and goblet cells and less inflammatory cell infiltration into the septal cartilage (P < .05) than the free graft group.

CONCLUSIONS

After reconstruction procedures for mucosal defects, histopathological differences were observed between the free graft and pedicled flap. Reconstruction with pedicled flaps had advantages including preservation of healthy mucosal epithelium and suppression of inflammation on the reconstruction site. This indicated that reconstruction with pedicled flaps might have advantages over that with free grafts.

LEVEL OF EVIDENCE

NA Laryngoscope, 131:E428-E433, 2021.

Effect of expanding nanocellulose sponge on nasal mucosal defects in an animal model

Nanocellulose has emerged for a wide range of applications in biomedical engineering because of its water absorption capacity, appropriate elasticity. We investigated the hemostatic and regenerative abilities of an expanding polyvinyl alcohol (PVA)-nanocellulose sponge on nasal mucosal defects. A 3 mm-diameter nasal defect was made in experimental rabbits. Rabbits were divided into four groups with control, vaseline, PVA and PVA-nanocellulose packing groups. After the defect was created, bleeding times and amounts were monitored. Packing materials were removed on experimental day (ED) 2. On ED 3, 7 and 14, histological analysis and immunohistochemical study for neutrophils were performed. Inflammatory cells were counted and epithelial thicknesses were evaluated. Bleeding amounts and times in the vaseline packing group were smaller than in the PVA groups. PVA-nanocellulose group showed less neutrophils than in the other groups on ED 7. Average epithelium thickness in the PVA-nanocellulose group was significantly smaller than in the control group at ED 7, but at ED 14, there was no significant intergroup difference. PVA-nanocellulose group had a significant lower inflammatory cell count than the control group on ED 7. PVA-nanocellulose sponge applied to nasal mucosal defects can significantly enhance mucosal regeneration during early wound healing.

Effects of submucosal PRP injection on wound healing in endonasal surgeries: an experimental study

PURPOSE

To investigate the effects of submucosal platelet-rich plasma (PRP) injection on nasal mucosal wound healing after endoscopic sinus surgery.

METHODS

24 New Zealand white rabbits were randomly divided into three groups. To mimic surgery, injury was created using 3-mm punch forceps on ventral turbinate mucosa for all groups. Submucosal PRP was injected to the damaged mucosa in the first group (PRP group, n = 8), where 0.9% saline solution to the second group (saline group, n = 8) and no injection to the third one (control group, n = 8). All the animals were sacrificed 14 days after surgery; histopathological examination and hydroxyproline measurements were performed on the mucosa of all groups.

RESULTS

Neutrophils, goblet cells, and collagen intensity were found significantly lower (p < 0.05) in PRP group than the control group. Also, the number of ciliary and goblet cells, and collagen intensity were found significantly lower (p < 0.05) in PRP group, than the saline group. In PRP group, hydroxyproline levels were found (p < 0.05) significantly lower than the saline and the control group, and no significant difference was found between the saline group and the control group (p > 0.05).

CONCLUSION

There are many studies in literature showing the positive effects of PRP on wound healing. The results of this study also demonstrated positive effects of PRP on the nasal mucosa. According to these results, PRP injection to the injured nasal mucosa showed anti-inflammatory, mucus-softening, and synechia-reducing effects. Therefore, submucosal PRP injection after endonasal surgeries can be considered an effective application for maintaining nasal physiology.

The Effects of Postoperative Astaxanthin Administration on Nasal Mucosa Wound Healing

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BACKGROUND

Wound healing of the nasal mucosa after endoscopic sinus surgery (ESS) is frequently complicated by scaring and consequently recurrences are encountered. Methods of optimizing results have been sought. In the present study we evaluated the effects of a powerful antioxidant, astaxanthin, on nasal mucosa healing after surgery, comparing it to the extensively studied properties of dexamethasone.

MATERIALS AND METHODS

63 Wistar rats were used. The nasal mucosa from one side was damaged employing the brushing method. They were randomly divided into three experimental groups, one treated with astaxanthin, the second treated with dexamethasone and the third one acted as the control and was given normal saline. The rats were killed on days 5, 14 and 28 following injury. We observed the temporal evolution of the wound healing process and quantified the results by assessing four parameters: the epithelial thickness index (ETI), the subepithelial thickness index (STI), the goblet cell count and the subepithelial fibrosis index (SFI).

RESULTS

At 28 days, the ETI was significantly lower in the astaxanthin group (p < 0.05) compared to the other two groups. The STI was also lower in the astaxanthin group (p < 0.05), but comparable to the dexamethasone group at 28 days. The goblet cell count was higher in the astaxanthin group. The SFI had similar results in both dexamethasone and astaxanthin groups, with lower values compared to the control group. In the astaxanthin group there was no synechia formation.

CONCLUSION

Astaxanthin given in the post injury period significantly decreases fibrosis, inhibits synechia development and significantly decreases subepithelial fibrosis. Moreover, it has no general or local toxic effects.

The Effects of Halofuginone on Wound Healing in the Rat Nasal Mucosa

Background

Halofuginone is an alkaloid febrifugine analogue and bioactive molecule that was isolated incidentally from the Dichroa febrifuga plant. The therapeutic efficacy of halofuginone in parasitic infections, scleroderma, inflammation, and fibrosis-related diseases, as well as in some types of cancer, has been previously reported. The effects of halofuginone on nasal mucosal damage are not yet known.

Objective

The aim of this study was to investigate the potential effect of topically applied halofuginone on wound healing in the mechanically injured nasal mucosa of rats.

Methods

A unilateral mucosal wound was created in the nasal cavity of 32 rats (aged 4 weeks) using the brushing technique. These rats were randomly divided into 4 groups. Although the control group did not receive an intervention, a dry pad, a saline-impregnated pad, or a pad impregnated with halofuginone were placed in the rats of the other 3 groups and left for 5 minutes. Rats were sacrificed on the 14th day, and a histological examination was performed. The nasal mucosa was assessed via hematoxylin-eosin and Masson’s trichrome staining.

Results

There were no statistically significant differences in epithelial thickness, inflammation, goblet cell formation, and epithelial disarray values between the halofuginone group and the control group ( P > .05). The subepithelial thickness was significantly decreased in the saline-treated group and the halofuginone-treated group ( P < .05), but a significantly lower level of subepithelial fibrosis was only observed in the halofuginone group compared to the other groups ( P < .05).

Conclusions

Topical halofuginone administration reduces the development of fibrosis and subepithelial edema after experimentally induced nasal mucosal injury, but it does not exert therapeutic or preventive effects on epithelial damage, inflammation, and goblet cell hyperplasia.

Lin E, Poetker DM, Garcia GJM. Clinical Importance of Nasal Air Conditioning: A Review of the Literature

Background

Nasal air conditioning (ie, heating and humidification of inspired air) is an important function of the nasal cavity. This function may be reduced in cases of aggressive nasal surgery. Future virtual surgery planning tools may be used to design surgical approaches that preserve the nasal air conditioning capacity while decreasing airflow resistance. However, it is unclear whether there is a threshold below which impaired nasal air conditioning is associated with negative health consequences.

Objective

This study aims to review the literature on the clinical impact of reduced nasal air conditioning and its implications for nasal surgery outcomes.

Methods

A literature search was performed on PubMed and Scopus databases for articles that investigated the effect of air temperature and humidity on mucociliary clearance, respiratory epithelial structure, and the prevalence and severity of respiratory diseases.

Results

Inspiration of cold, dry air has direct effects on the respiratory epithelium, such as reduced mucociliary clearance and loss of cilia. Nasal surgeries do inflict some changes to the nasal mucosa and geometry that may result in decreased heating and humidification, but it is unclear how long these effects last. Laryngectomy patients serve as a human model for the absence of nasal air conditioning. The heat and moisture exchangers that many laryngectomy patients wear have been shown to improve lung function and reduce pulmonary symptoms associated with breathing unconditioned air, such as increased coughing and thickened mucus.

Conclusion

Nasal air conditioning is an important mechanism to maintain mucociliary clearance and prevent infection by inhaled pathogens. Preservation of nasal air conditioning capacity should be considered in the implementation of future virtual surgery planning tools. However, a threshold for the onset of negative health consequences due to impaired nasal air conditioning is not yet available.

Establishment and verification of a mouse model of nasal wound healing

OBJECTIVES

Poor wound healing as reflected by the development of synechia and osteitis after endoscopic sinus surgery may trigger disease recurrence. Animal models provide insights into the pathogenesis of poor wound healing and may aid in the development of new therapeutics. Here, we established a mouse model of nasal wound healing and confirmed its utility.

STUDY DESIGN

Animal study.

METHODS

Unilateral intranasal wounds were induced using a small interdental brush in 6-week-old C57BL/6 mice. Forty-five mice were divided into three groups (each n = 15): one control and two experimental groups (intranasal vs. intraperitoneal dexamethasone). Mice were sacrificed on days 2, 14, and 28 after injury (each n = 5). Serial changes in nasal wound histopathology were described, and intergroup differences were analyzed.

RESULTS

On day 2, mucosal detachment, hemorrhage, and exudate were observed. On day 14, synechiae featuring neo-osteogenesis (bone lacunae, osteoblasts, and multinucleated osteoclasts) between the septum and the maxilloturbinate were prominent, followed by wound maturation on day 28: fewer lacunae and smaller osteoblasts. Macrophages were evident only on day 2, and lymphocytes were predominant on day 28. The amount of exudate on day 2 and the synechial area on day 28 were significantly reduced in mice that received dexamethasone systemically compared with control mice, with similar trends in those treated intranasally.

CONCLUSION

Our mouse model of nasal wound healing was characterized by the development of bony synechia and neo-osteogenesis, not soft-tissue synechia. The model may be useful in the assessment of novel therapeutics to prevent those wounds.

LEVEL OF EVIDENCE

NA Laryngoscope, 129:E266-E271, 2019.

Topical Corticosteroid Pretreatment Mitigates Cellular Damage After Caustic Injury to the Nasal Upper Airway Epithelium

BACKGROUND

Topical corticosteroids are currently employed to reduce established airway inflammation; their prophylactic use might help limit cellular damage against harmful stimuli.

OBJECTIVES

To determine the effects of a prophylactic topical application of budesonide (BD) on an in vivo nasal epithelium injury model induced by trichloroacetic acid (TCA).

METHODS

C57Bl/6 mice were exposed to intranasal TCA topical application. Three groups received topical intranasal BD, saline solution, or no intervention prior to a single topical exposure to TCA. Controls were not exposed to TCA. Whole nasal cavity coronal sections were analyzed at 1, 3, and 6 days postinjury at tissue and cellular levels using histopathological analysis, immunofluorescent staining, and fresh tissue RNA microarray analysis.

RESULTS

Prophylactic topical corticosteroid exposure protected the nasal epithelium from acute damage, maintaining epithelial thickness and cell survival. Six days following TCA exposure, epithelial and cellular changes were less pronounced on the BD-treated group compared to all exposure groups. The microarray analysis was used to evaluate the gene transcripts in all treatment groups. Ciliary tip protein, Sentan, and submucosal protein S100b were identified as potential factors in epithelial airway protection; immunofluorescent staining corroborated their presence and location within the respiratory epithelium.

CONCLUSION

Topical corticosteroid treatment to the nasal epithelium can mitigate several of the early deleterious effects of acute epithelial damage in experimental airway injuries caused by TCA. These findings suggest a novel, direct cytoprotective effect of corticosteroids on the nasal epithelium, and the potential of expanding the use of prophylactic periprocedural topical corticosteroids for respiratory epithelial tissues.

Corticopuncture Facilitated Microimplant-Assisted Rapid Palatal Expansion

Introduction

Microimplant-assisted rapid palatal expansion (MARPE) has been considered an alternative to avoid extensive surgical procedures. In order to obtain skeletal results of MARPE, force should be enough to overcome areas of resistance and the first one that is required to be disrupted is the midpalatal suture, which becomes increasingly interdigitated after adolescence.

Objective

The present study aimed at providing a novel approach using a minimally invasive method called corticopuncture (CP) in association with MARPE illustrated by a case report of a 35-year-old Brazilian female Caucasian patient presenting maxillary transverse deficiency.

Method

Treatment plan started with an orthopedic correction of the transverse problem using a MARPE device. After many unsuccessful attempts to activate MARPE, corticopunctures were performed along the midpalatal suture. CP procedure at the midpalatal suture included 8 perforations (2 mm apart), performed after previous predrilling followed by miniscrew insertion (5 mm thread length and 1.8 mm diameter).

Results

After CP and new activation protocol, the opening of the midpalatal suture was observed by CBCT images, showing skeletal results, suture split of 3.14 mm (premolar area) and 2.06 (molar area), an increase of 4.3 mm (premolar) and 3.03 mm (molar) in basal bone width, 4.43 mm (premolar) and 3.1 mm (molar) in cortical bone width, and minimal dental effects (mean of 1.2° of tooth tipping).

Conclusion

The combination of MARPE and corticopuncture method was proved to be a nonsurgical treatment option to correct maxillary transverse deficiency in an adult patient. CP was able to weaken suture interdigitation thus facilitating the split.

Histopathological effects of septoplasty techniques on nasal septum mucosa: an experimental study

OBJECTIVE

The aim of this study is to evaluate the histopathological effects of septoplasty techniques on the nasal septal mucosa of rabbits with light and electron microscope.

METHODS

The study was performed on 21 rabbits between August 2016 and February 2017. Rabbits were randomly divided into three groups. In Group-1, while preserving the L-strut structure of the septum, cartilage resection, was performed by open technique septoplasty. In Group-2, the same procedure was done except the resected cartilage was crushed and put back in place. No surgical procedure was performed on the Control group. Postoperative 2nd month; the specimens were histopathologically evaluated by light and electron microscope in terms of changes in the morphology of septum mucosa, perichondrial thickness, cilia and goblet cell deprivation, loss in glands, fibrosis and inflammatory cell infiltration in the lamina propria.

RESULTS

The deprivation in cilia, goblet cells, serous gland and increase in the amount of collagen fibers were examined in both Group-1 and 2. The difference in Group-1 and Group-2 were statistically significant in terms of presence of cilia, number of goblet cells and glands and increase in collagen fibers when compared to control (p < 0.001, p = 0.002, p = 0.020, p = 0.002, respectively). In terms of perichondrium thickness, statistically significant difference was found between the Control and Group-2 (p < 0.001). CONCLUSıON: In this study, histopathological findings supported that the presence of cartilage in the septum is necessary to prevent the mucosal changes. Long-term studies are needed to observe whether changes in the morphology of epithelium and gland proceed more than 2 months follow-up.

Effects of oral ısotretinoin on normal and wounded nasal mucosa: an experimental study

BACKGROUND

We aimed to investigate the effect of systemic isotretinoin therapy on normal and wounded nasal septal mucosa histopathologically in an experimental rabbit model.

METHODS

Circular mucosal defect with a 7 mm diameter was made in the left septum of 12 New Zealand white rabbits. The rabbits were divided into two groups (six rabbits in each group) oral isotretinoin was given with olive oil at the operation day to the first group. The control group was only oil given group. The harvested septum mucosas were divided into four groups (1-wounded-drug given side, 2-unwounded and drug-given side, 3-wounded-control and 4-unwounded-control side). The diameter of the defect, mucosal thickness, epithelial thickness, ciliated cell level, goblet cell level and inflammation were evaluated every week for 4 weeks.

RESULTS

At both wounded and normal side, thinning of normal respiratory ciliated epithelium was observed in the postoperative period. In study group at the wounded side; mean mucosal thickness was measured 139.66 µ (± 26.24), and in the control group, mean mucosal thickness was 238.33 µ (± 39.7) at the wounded side. (p < 0.001). The difference between the groups in thickness of normal septal mucosa was also statistically significant (p = 0.016) [190 µ (± 14.6) and 256.66 µ (± 44.66)]. The average cilia level was observed 1.16 in the wounded study group, while the average level was 2.33 in the wounded control group (p = 0.012). Average score measurements of the regenerated mucosa suggested that isotretinoin-given wounded animals have reduced goblet cell recovery, compared to the control both on the regenerated and unwounded mucosas (p = 0.007, p = 0.002, respectively). Inflammation was significantly higher in the wounded isotretinoin group (p = 0.018).

CONCLUSION

Oral isotretinoin has negative effects on epithelial and ciliary regeneration, significantly reduces mucosal thickness and goblet cell counts of the normal and regenerated mucosa, causes severe inflammation and significant reactive changes.

Random nasoseptal flap for revision skull base reconstruction

The nasoseptal flap (NSF) has become the workhorse of endoscopic skull base reconstruction (ESBR). With the increase in endoscopic skull base procedures, there has also been the need for staged and revision procedures where the use of the NSF is no longer an option. These cases have posed new and interesting challenges to skull base surgeons especially with regards to reconstructive options. While free mucosal or turbinate grafts may be too small for certain defects, others such as the pericranial flap require an open procedure with added morbidity. We describe the use of a random nasoseptal flap for the reconstruction of a skull base defect.

Non-thermal plasma treated solution with potential as a novel therapeutic agent for nasal mucosa regeneration

Adequate and rapid mucosal regeneration is one of the most important factors in the healing process of nasal mucosa after surgery or trauma. In particular, delayed mucosal regeneration after surgery is an important cause of surgical failure. However, no effective treatment is available yet. Non-thermal plasma (NTP) has several medical effects, but the existing probe type is limited to local direct treatment. Therefore, we investigated the various effects using liquid type plasma to overcome this limitation. In addition, the therapeutic effects of non-thermal plasma treated solution (NTS) on nasal mucosa have yet to be determined. Experiments were carried out using BEAS-2B, a human bronchial epithelial cell line similar to nasal mucosa epithelium. NTS had no cytotoxicity to the BEAS-2B cells and enhanced cell proliferation. NTS also promoted migration of BEAS-2B cells. NTS increased cell proliferation and migration via epidermal growth factor receptor (EGFR) activities and epithelial-to-mesenchymal transition (EMT) signaling. Furthermore, NTS enhanced wound healing of nasal mucosa in an animal model. Accordingly, NTS promotes nasal mucosa wound healing by increasing cell proliferation and migration. These findings suggest the therapeutic potential of NTS in nasal mucosa wound healing.

The Effects of Curcumin on Wound Healing in a Rat Model of Nasal Mucosal Trauma

We explored the effects of topical curcumin on the healing of nasal mucosal wounds. A total of 32 Sprague-Dawley Albino rats were randomized in equal numbers into four groups, and unilateral nasal wounds were created using an interdental brush. Group 1 (the sham-control group) contained untreated rats with traumatized right-side nasal cavities; Group 2 and 3 rats were similarly traumatized and treated with topical curcumin (5 and 10 mg/mL) dissolved in dimethyl sulfoxide daily for 7 days after trauma; Group 4 rats were treated with topical dimethyl sulfoxide only. All rats were decapitated on day 15 and the healing sites evaluated by blinded observers in terms of the presence of cellular hyperplasia, goblet cell hypertrophy and degeneration, leucocytic infiltration, ciliary loss and degeneration, edema, and vascular dilation. On histopathological evaluation, all of cellular hyperplasia, leukocytic infiltration, and edema were significantly reduced in Group 3 compared with Group 1 (p = 0.001, p = 0.004, and p = 0.008, resp.). Thus, curcumin reduced the inflammatory response and significantly accelerated wound healing.

Healing of the nasal septal mucosa in an experimental rabbit model of mucosal injury

Objective

The aim of this study was to investigate the regeneration process of the nasal mucosa after a surgically created mucosal defect in the rabbit nasal septum, and to evaluate the effects of different interventions.

Methods

A 7 mm-diameter circular mucosal defect was made in the septum of forty New Zealand white rabbits. The rabbits were divided into four groups (ten rabbits in each group) according to the type of intervention; no treatment (control), silastic sheet (SS), hyaluronic acid (HA), and silastic sheet and hyaluronic acid (SS + HA) group. The diameter of the defect, mucosal thickness, epithelial thickness, and ciliated cell count were evaluated every week for five weeks.

Results

The average diameter of the defect in the control group were 5.1, 3.65, 1.2, 0.75, and 0.05 mm at postoperative 1, 2, 3, 4, and 5 weeks. In the SS group, the diameter decreased to 4.35, 2.1, 0.35, 0.15, and 0 mm at postoperative 1, 2, 3, 4, and 5 weeks, respectively, in which the mean diameter of the postoperative week 2 was significantly smaller compared to control (3.65 mm vs. 2.1 mm, P = 0.039). For the HA group and SS + HA group, the diameter of the defect did not show a significant difference from the control group during the five weeks. The mucosal thickness, epithelial thickness, and ciliated cell count of the regenerated mucosa were not significantly different among the groups.

Conclusion

The regeneration process of the nasal septal mucosa was identified using a novel rabbit model. Mucosal regeneration can be accelerated by applying silastic sheets.

Effect of Cigarette Smoke on Wound Healing of the Septal Mucosa of the Rat

Objectives/Hypothesis. Proper wound healing following endoscopic sinus surgery (ESS) is influenced by several factors, like cigarette smoke (CS) exposure. This study aims to assess the influence of cigarette smoke on the healing of induced septal mucosal lesion in rats. Methods. Unilateral nasal wounds were created by means of the interdental brush in seventy-four-week-old male rats. Animals were randomly divided into two groups: control group and CS exposure group, each comprising 35 animals, divided into five groups (n = 7). Animals were sacrificed in groups of seven on day 2 and then on days 5, 14, and 28 and finally on day 42 following wound induction. Results. Histological analysis of mucosal specimens shows important changes at the CS exposure group. Starting with the infiltrates of neutrophils, eosinophils, macrophages, and lymphocytes, the histological changes were continued with the Goblet cell proliferation, ciliated cells loss, fibrosis, and epithelial and subepithelial hypertrophy. Conclusion. In this experimental model of nasal wound healing we demonstrated the deleterious effects of chronic CS exposure. The adverse effects of CS exposure are firstly a postponement of the healing process and secondly the persistence of inflammation which becomes chronic.

The Effect of Propolis in Healing Injured Nasal Mucosa: An Experimental Study

Introduction

 Mechanical trauma to the nasal mucosa increases the risk of synechia formation, especially after chronic rhinosinusitis and nasal surgeries.

Objective

 This study was carried to assess the effect of propolis administration in healing injured nasal mucosa in rats.

Methods

 We randomly divided eighteen rats into three equal experimental groups: (1) non-treated group; (2) gum tragacanth (suspending agent for propolis) treated group; and (3) propolis treated group. The non-treated group received no treatment for 15 days. The second group received gum tragacanth administration (5 ml/kg, orally) once daily for 15 days. The third group received propolis suspension orally at a dose of 100 mg/kg once daily for 15 days. At the beginning of this study, we induced unilateral mechanical nasal trauma on the right nasal mucosa of all rats in the three groups using a brushing technique. A pathologist stained tissue samples using hematoxylin and examined eosin by using a light microscope.

Results

 The severity of inflammation was milder with the absence of ulcerations in the propolis treated group compared with the non-treated and gum tragacanth groups. Goblet cell and ciliated cell loss was substantially lower in patients treated with propolis compared with groups without treatment and those treated with gum tragacanth.

Conclusion

 Propolis decreased inflammation and enhanced healing of wounds of the nasal mucosa in rats.

Efficacy of N-Acetylcysteine on Wound Healing of Nasal Mucosa

Postoperative nasal mucosa healing is a highly complex and organized process, and the success rates of endoscopic sinus surgery and septoplasty surgeries are closely associated with the postoperative wound healing processes. In this experimental study, the authors' aim was to use histopathologic examination to investigate the effects of N-Acetylcysteine (NAC) on the wound healing of rat nasal mucosa after mechanical trauma. Twenty-one Sprague-Dawley rats were randomly divided into 3 groups: the nontreated group (N = 7), the control saline group (N = 7), and the NAC group (N = 7). No treatment was given to the nontreated group for 15 days. The control saline group received intraperitoneal injection of saline (2.5  mL/kg, intraperitoneal) for 15 days and the NAC group was intraperitoneally injected with NAC at a dose of 300  mg/kg/day for 15 days. At the beginning of the study, unilateral mechanical nasal trauma was induced with an interdental brush inserted through the right nostril in all rats. Samples were stained using hematoxylin and eosin solution, and were examined by a pathologist using a light microscope. The severity of inflammation was milder in the NAC group compared with that in the nontreated and saline groups (P < 0.05). The subepithelial thickness index was lower in the experimental group (P < 0.05). Goblet cell loss was reduced in the experimental group compared with the nontreated and saline groups (P < 0.05). NAC decreases inflammation and goblet cell loss. Therefore, NAC has potential beneficial effects on the wound healing of nasal mucosa in rats.

Inhibitory effect of prostaglandin E(2) on the migration of nasal fibroblasts

BACKGROUND

Fibroblast migration is crucial for normal wound repair after sinonasal surgery. Prostaglandin E2 (PGE2) is a potent inhibitor of fibroblast functions including chemotaxis, proliferation, and matrix production. The purpose of this study was to determine whether PGE2 affects the migration of nasal fibroblasts and to investigate the mechanism of action of PGE2 on nasal fibroblasts.

METHODS

Primary cultures of nasal fibroblasts were established from inferior turbinate samples. Fibroblast migration was evaluated with scratch assays. Reverse-transcription polymerase chain reaction was performed for E prostanoid (EP) 1, EP2, EP3, and EP4 receptors. EP receptor-selective agonists and antagonists were used to evaluate receptor functions. Stimulatory G (Gs) proteins were activated to evaluate mechanisms. Intracellular cyclic adenosine monophosphate (cAMP) levels were measured by ELISA, and fibroblast cytoskeletal structures were visualized with immunocytochemistry.

RESULTS

PGE2 significantly reduced the migration of nasal fibroblasts. Agonists selective for the EP2 and EP4 receptors significantly reduced the nasal fibroblast migration. Antagonists of the EP2 and EP4 receptors inhibited the effect of PGE2 on nasal fibroblast migration. Activation of Gs protein and adenyl cyclase reduced nasal fibroblast migration.

CONCLUSION

PGE2 inhibited the migration of nasal fibroblasts via the EP2 and EP4 receptors, and this inhibition was mediated by cAMP elevation. Targeting specific EP receptors could offer therapeutic opportunities for conditions such as delayed wound healing after nasal surgery.

Regenerative medicine and nasal surgery

Nasal surgery is a constellation of operations that are intended to restore form and function to the nose. The amount of augmentation required for a given case is a delicate interplay between patient aesthetic desires and corrective measures taken for optimal nasal airflow. Traditional surgical techniques make use of autologous donor tissue or implanted alloplastic materials to restore nasal deficits. Limited availability of donor tissue and associated harvest site morbidity have pushed surgeons and researchers to investigate methods to bioengineer nasal tissues. For this article, we conducted a review of the literature on regenerative medicine as it pertains to nasal surgery. PubMed was searched for articles dating from January 1, 1994, through August 1, 2014. Journal articles with a focus on regenerative medicine and nasal tissue engineering are included in this review. Our search found that the greatest advancements have been in the fields of mucosal and cartilage regeneration, with a growing body of literature to attest to its promise. With recent advances in bioscaffold fabrication, bioengineered cartilage quality, and mucosal regeneration, the transition from comparative animal models to more expansive human studies is imminent. Each of these advancements has exciting implications for treating patients with increased efficacy, safety, and satisfaction.

Effects of caffeic acid phenethyl ester on wound healing of nasal mucosa in the rat: an experimental study

PURPOSE

Wound healing of the nasal mucosa is a highly complex process that restores the anatomical and functional integrity of tissue that has been exposed to trauma. In this experimental study, our aim was to use histopathological examination to investigate the effects of caffeic acid phenethyl ester on the wound healing of rat nasal mucosa after mechanical trauma.

MATERIALS AND METHODS

The rats were randomly divided into 3 experimental groups: a non-treated group (n=7), a control saline group (n=7) and a caffeic acid phenethyl ester group (n=7). The non-treated group received no treatment for 15 days. The second group was administered saline (2.5 mL/kg, intraperitoneal) once a day for 15 days. The third group received caffeic acid phenethyl ester intraperitoneally at a dose of 10 μmol/kg once a day for 15 days. At the beginning of the study, unilateral mechanical nasal trauma was induced on the right nasal mucosa of all rats in the three groups using a brushing technique. Samples were stained using hematoxylin and eosin solution and were examined by a pathologist using a light microscope.

RESULTS

The severity of inflammation was milder in the caffeic acid phenethyl ester group compared with that in the non-treated and saline groups (P<0.05). The subepithelial thickness index was lower in the experimental group (P<0.05). Goblet cell and ciliated cell loss was substantially reduced in the experimental group compared with the non-treated and saline groups (P<0.05).

CONCLUSIONS

Caffeic acid phenethyl ester decreases inflammation and the loss of goblet cells and ciliated cells. Therefore, caffeic acid phenethyl ester has potential beneficial effects on the wound healing of nasal mucosa in the rat.

Effects of topical phenytoin on nasal wound healing after mechanical trauma: An experimental study

OBJECTIVES/HYPOTHESIS

Impaired postoperative wound healing is the second most common morbidity after synechia formation in endoscopic sinus surgery. The aim of this experimental study was to investigate the potential effects of topical phenytoin on wound healing after nasal mucosal trauma in rats.

STUDY DESIGN

An experimental study at the Inonu University Faculty of Medicine.

METHODS

Twenty-four rats were randomized into three groups: 1) phenytoin group (n = 8), 2) control group (n = 8), and 3) vehicle group (n = 8). After damaging the right nasal cavity, in the phenytoin group, 1% topical phenytoin cream was applied for 7 days. The rats in the control group did not receive any treatment. The vehicle group was treated with daily topical cold cream for 1 week. The rats were sacrificed at the end, and the nasal cavities were excised. Tissue edema and inflammatory cell infiltration were compared among the groups. Additionally, proliferating cell nuclear antigen (PCNA) and cluster of differentiation 31 (CD31) immunoexpression levels were evaluated. Furthermore, in biochemical analysis, the tissue levels of vascular endothelial growth factor and (EGF) of the groups were investigated.

RESULTS

In the phenytoin group, tissue edema and inflammatory cell infiltration were significantly decreased, and PCNA and CD31 immunoexpression levels were more prominent (P < .001) and the tissue EGF levels were significantly higher (P < .01).

CONCLUSIONS

Topical phenytoin treatment may alter the nasal wound healing after mechanical trauma. The potential beneficial effects of topical phenytoin on nasal mucosa should be investigated by further experimental and human trials.

LEVEL OF EVIDENCE

NA.

Nasal epithelial repair and remodeling in physical injury, infection, and inflammatory diseases

PURPOSE OF REVIEW

To summarize the current knowledge of cellular and molecular mechanisms of nasal epithelial repair and remodeling during physical and pathophysiological conditions.

RECENT FINDINGS

Nasal epithelial repair and remodeling is a highly organized and well coordinated process, involving inflammation, proliferation, differentiation, matrix deposition, and remodeling, and is regulated by a wide variety of growth factors and cytokines. From the in-vivo and in-vitro studies conducted in both human and animal models, undifferentiated basal cells (progenitors) are able to migrate from adjacent epithelium, spread over the denuded basement membrane, and proliferate in injured regions (self-renewal) in necessary (homeostasis) or excessive (hyperplasia) degree. Progenitor cells reorient to an apical-basal polarity, and progressively differentiate into ciliated and nonciliated columnar cells and goblet cells, reconstituting a functional respiratory epithelium after several weeks. This recovery process can be observed during various types and severity of injury, and also in common nasal diseases, including acute viral, allergic, and nonallergic rhinitis, as well as chronic rhinosinusitis with and without nasal polyps.

SUMMARY

Although nearly 10 000 articles about nasal epithelium have been published in the last decade, the mechanisms underlying the nasal epithelial repair are still understood at only a superficial descriptive level. In order to advance rhinology to the next level of a comprehensive knowledge of the orchestrated genetic and molecular processes acting during epithelial repair, combined clinical and experimental studies using sophisticated investigational plans to elucidate the functions of both the protein-coding and regulatory portions of the human genome are required.

Effect of dexamethasone on wound healing of the septal mucosa in the rat

BACKGROUND

Postoperative treatment after functional endoscopic sinus surgery (FESS) aims to modulate the wound healing process. Systemic or topically applied corticosteroids have been reported to be beneficial for improving nasal wound healing after FESS. However, few studies have investigated the effects of postoperative systemic steroids on nasal wound healing with regard to histological changes. The aim of this study was to evaluate the effect of systemic dexamethasone on nasal wound healing after mechanical injury in the rat.

METHODS

A unilateral wound in the nasal cavity was induced using the brushing technique in 4-week-old, Sprague-Dawley rats (n = 70). Dexamethasone (0.15 mg/kg daily for 7 days) and normal saline were administered i.p. to the experimental and control groups (n = 35 for each) after the injury. The rats (n = 7 for each) were killed on days 2, 5, 14, 28, and 42 after the injury. Histological changes in the nasal mucosa were examined and compared using hematoxylin and eosin and Masson's trichrome staining.

RESULTS

The experimental group showed less subepithelial edema formation and epithelial disarray at the early phase of the wound healing period. There were statistically significant differences in the subepithelial thickness and epithelial thickness indices between the experimental and control groups (p < 0.05). Ciliary and goblet cell indices were lower in the experimental group, which means that ciliary and goblet cell regeneration may be delayed by dexamethasone (p < 0.05). There were no differences in the subepithelial fibrosis index between the two groups. Adhesion formation between the nasal septum and turbinate were found only in the control group.

CONCLUSION

Systemic dexamethasone after mucosal injury may lessen subepithelial edema, goblet cell hyperplasia, and adhesion formation; however, it may cause delayed mucosal ciliary regeneration.

Effects of microelectrical current on migration of nasal fibroblasts

BACKGROUND

Migration of fibroblasts is critical in wound healing. The question of how wounded electric fields guide migration of nasal fibroblasts remains to be elucidated. This study was designed to determine morphology, directedness, and migration rate of nasal fibroblasts during microcurrent application, which is simulated by an endogenous electric field at the vicinity of the wound.

METHODS

Nasal fibroblasts were exposed to a microelectric field at 50, 100, and 250 mV/mm for 3 hours at 37°C. In this experiment, the field polarity was reversed for an additional 3 hours. During in vitro testing, the cells were incubated in a newly developed miniature, microcurrent generating chamber system, with 5% CO(2), at 37°C; the media was circulated by a pump system. A wound was created by scratching a cell-free area (∼150 μm wide) into a confluent monolayer. The average migration speed was calculated as the distance traveled by the cell divided by time.

RESULTS

A microelectric field of 100 mV/mm or more induced significant cell migration in the direction of the cathode. Trajectory speeds at 50, 100, and 250 mV/mm were 9.8 ± 0.3, 11.8 ± 0.3, and 13.5 ± 0.9 μm/mm, respectively. A significant difference was observed between migratory rate of controls and that of 50 mV/mm (p < 0.05).

CONCLUSION

Microelectric fields appear to have a crucial role in control of nasal fibroblast activity in the process of wound healing.