Regenerating human nasal mucosa cells express peptide growth factors

The therapeutic effects of basic fibroblast growth factor in nasal vestibulitis

OBJECTIVE

To observe the effect of topical application of recombinant human basic fibroblast growth factor (bFGF) in patients with nasal vestibulitis.

METHODS

One hundred patients with nasal vestibulitis were randomly divided into two groups. Local application of bFGF + conventional medication was administered in the treatment group, while conventional medication was conducted in the control group. The healing of the nasal vestibular mucosa was observed.

RESULTS

The mucosal healing time was 18.3 ± 4.8 days in the treatment group and 36.2 ± 6.2 days in the control group. The data comparison revealed that the difference between groups was statistically significant (P < 0.01). The total effective rate was 98.0% in the treatment group and 90.0% in the control group, and the difference was not statistically significant between the two groups (P > 0.05).

CONCLUSION

Topical application of bFGF in patients with nasal vestibulitis could promote the growth of nasal mucosa, shorten the healing time of mucosal erosion, enhance the clinical treatment effect, and save a lot of treatment time for patients.

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.

Transforming Growth Factor β1 in Nasal Remodeling: Differences between Chronic Rhinosinusitis and Nasal Polyposis

Background

Chronic rhinosinusitis (CRS) and nasal polyposis (NP) are histopathologically characterized by different gross morphological aspects. Transforming growth factor (TGF) β1 plays an important role in tissue remodeling, which is poorly understood in chronic diseases of the sinuses.

Methods

The expression of TGF-β1 was analyzed by enzyme-linked immunosorbent assay, quantitative reverse-transcription polymerase chain reaction, and immunohistochemistry in nasal tissue from controls (n = 6), CRS (n = 19), or NP (n = 19).

Results

CRS presented significantly higher concentrations of TGF-β1 at protein (p = 0.0008) and mRNA levels (p = 0.025) when compared with NP samples. In CRS, TGF-β1+ staining of the extracellular matrix was found abundantly and related to fibrosis. In contrast, no TGF-β1 staining was found in the pseudocyst areas in NP.

Conclusions

CRS was histologically characterized by fibrosis, which was reflected by a significantly higher expression of TGF-β1 at RNA and protein levels when compared with NP. We show that TGF-β1 expression is related to fibrosis, differentiating CRS without polyps from NP.

Differential Effects of Insulin-Like Growth Factors on Scratch Wound Repair in Respiratory Epithelial Cells

Background

Insulin-like growth factors (IGFs) I and II, being potent promoters of cellular growth and differentiation, were investigated for their effectiveness in improving the rate of scratch closure in human respiratory epithelium in vitro.

Methods

Human epithelial cell lines from the nasal, bronchial, and tracheal regions were analyzed for their response to IGF-I and IGF-II, in a confluent monolayer scratch assay. IGF-binding proteins (IGFBPs) produced by certain cells are able to reduce the effectiveness of the IGFs. Consequently, the analogues LongR3 IGF-I, Des1–3 IGF-I and Arg3 IGF-I were investigated also because of their lower affinity for the IGFBPs, while still retaining unaffected affinity for the IGF-I receptor.

Results

All growth factors that were analyzed significantly improved the rate of scratch closure in bronchial and tracheal epithelial cells (p ≤ 0.05). In comparison, scratch closure was markedly slower in nasal epithelial cells and IGF-I was the most effective growth factor at effecting scratch closure in these cells. The IGF-I analogues did not significantly improve scratch closure compared with IGF-I, despite the presence of IGFBP-3 in nasal, bronchial, and tracheal epithelial cells.

Conclusion

Addition of IGF-I to wounded nasal epithelial cells increases the rate of scratch closure and therefore may have potential for improving the healing of the nasal mucosa.

Wound Healing of the Nasal and Paranasal Mucosa: A Review

Background

Wound healing is a highly coordinated process involving clot formation, inflammatory reaction, immune response, and, finally, tissue remodeling and maturation. Only few data regarding the specific healing of the nasal or sinusal mucosa are available.

Methods

After a short summary of the general principles of wound healing, the most important data regarding in vitro or in vivo models of wound healing of the nasal and paranasal mucosa are discussed. Attention is paid to clinical application.

Main Findings

First observations regarding the specific regulation of epithelial regeneration by growth factors have underlined the complex relationship between extracellular matrix and epithelium during the repair process. However, only poor and aspecific correlations can be described between endoscopically and histomorphologically defined postoperative phases.

Hormonal changes causing rhinitis in pregnancy among Malaysian women

Objectives:

To investigate the aetiology of rhinitis occurring in pregnancy, by (1) describing the relationship between pregnancy rhinitis and serum oestrogen, progesterone, placental growth hormone and insulin-like growth factor, and (2) assessing the prevalence of pregnancy rhinitis among Malaysian women.

Methods:

Prospective study involving 30 pregnant women followed at an ante-natal clinic for 14 months. Hormone levels were analysed during pregnancy and the post-partum period.

Results:

Levels of all four hormones were elevated in the third trimester, compared with first trimester and post-partum values. Rhinitis patients had higher levels of oestrogen and insulin-like growth factor 1 in the third trimester than non-rhinitis patients, although these differences were not statistically significant. The prevalence of rhinitis was 53.3 per cent, with most cases occurring in the third trimester. Patients with pregnancy rhinitis had a higher prevalence of female babies, compared with non-rhinitis patients (p = 0.003).

Conclusions:

Pregnancy rhinitis was significantly more common in women giving birth to female babies. Women with pregnancy rhinitis had a non-significant elevation in oestrogen and insulin-like growth factor 1 levels, compared with those without rhinitis.

The Etiology and Management of Pregnancy Rhinitis

Pregnancy rhinitis is defined as nasal congestion in the last 6 or more weeks of pregnancy, without other signs of respiratory tract infection and with no known allergic cause, with complete resolution of symptoms within 2 weeks after delivery. Pregnancy rhinitis occurs in approximately one-fifth of pregnancies, can appear at almost any gestational week, and affects the woman and possibly also the fetus. The pathogenesis of pregnancy rhinitis is not clear, but placental growth hormone is suggested to be involved. Smoking and sensitization to house dust mites are probable risk factors. It is often difficult to make a differential diagnosis from sinusitis: nasendoscopy of a decongested nose is the diagnostic method of choice. In some cases ultrasound or x-ray may be necessary. Sinusitis should be treated aggressively with increased doses of beta-lactam antibiotics and antral irrigation. Nasal decongestants give good temporary relief from pregnancy rhinitis, but they tend to be overused, leading to the development of rhinitis medicamentosa. Corticosteroids have not been shown to be effective in pregnancy rhinitis, and their systemic administration should be avoided during pregnancy. Nasal corticosteroids may be administered to pregnant women when indicated for other sorts of rhinitis. Nasal alar dilators and saline washings are safe means to relieve nasal congestion, but the ultimate treatment for pregnancy rhinitis remains to be found.

Clinical and pathogenetic characteristics of pregnancy rhinitis

Pregnancy rhinitis is a very common condition. Defined as "nasal congestion present during the last 6 or more weeks of pregnancy without other signs of respiratory tract infection, and with no known allergic cause, disappearing completely within 2 wk after delivery," it strikes one in five pregnant women, and it starts in almost any gestational week. The pathogenesis is not clear, but placental growth hormone is suggested to be involved. Smoking and sensitization to house dust mites are probable risk factors. It is often difficult to make a differential diagnosis from sinusitis, which may in pregnancy present with nasal congestion as the only symptom. Antral irrigation is diagnostic for purulent sinusitis and often needs to be repeated, as it should be treated intensively. Because of changes in pharmacokinetics, increased dosage of betalactam antibiotics is needed during pregnancy. As pregnancy rhinitis reduces quality of life and possibly also affects the fetus, there is often need for treatment. Nasal corticosteroid shave not been shown to be effective. Systemic administration should be avoided,but nasal corticosteroids could be used in pregnancy when indicated for other sorts of rhinitis. Nasal decongestants give good temporary relief, so pregnancy rhinitics tend to overuse them, giving an additional rhinitis medicamentosa. Therefore, use of nasal decongestants should be restricted to a few days. Invasive methods of turbinate reduction may be effective but are not recommendable in this self-limiting condition because of side effects. Nasal saline washings, exercise, and mechanical alar dilators are safe general means to relieve nasal congestion, but the ultimate treatment remains to be found.

The Role of Growth Factors for Disease and Therapy in Diseases of the Head and Neck

Growth factors are a large family of polypeptide molecules that regulate cell division in many tissues by autocrine or paracrine mechanisms. Depending on what receptors are activated, growth factors can initiate mitogenic, antiproliferative, or trophic effects, that is, growth factors act as positive or negative modulators of cell proliferation. Therefore, growth factors do not only play an important role in embryonic development and adult tissue homeostasis, but also in pathological situations like infection, wound healing, and tumorigenesis. Consequently, the application of growth factors, or vice versa the application of substances which are directed against growth factors like antigrowth factor antibodies, may have therapeutic applications. This review provides a brief account of what we know regarding growth factors in otorhinolaryngology, particularly in the field of otology, wound healing, oncology, peripheral nerve regeneration, and rhinology.

Prevalence and pathogenesis of sleep apnea and lung disease in acromegaly

Respiratory disorders are common and important complications in acromegaly. Patients suffering from acromegaly display a 1.6-3.3 fold increase in mortality rate, which is due to respiratory disorders in 25% of cases. In these patients, mortality for lung disease is 2-3 fold higher than in the general population. Every portion of the respiratory system may be involved. Deformities of facial bones, edema and hypertrophy of the mucosae and pharyngeal and laryngeal cartilages, enlargement of the tongue and inspiratory collapse of the hypopharinx, all may contribute to respiratory alterations. Nasal polyps, "hormonal rhinitis", changes of the voice and snoring are common occurrences. Though rarely, a laryngocele may ensue. Pneumomegaly is frequently observed and, as suggested by functional studies, might be due to an increased number rather than volume of the alveoli. An obstructive respiratory syndrome caused by mucosal thickening of the upper airways and bronchi is observed in 25% of female and 70% of male patients. The sleep apnea syndrome (SAS) affects 60-70% of acromegalic patients. SAS may be of obstructive, central or mixed type. Obstructive SAS is the prevailing form in acromegaly. It is due to intermittent obstruction of upper airways with preserved activity of the respiratory center, as testified by the remarkable thoracic and abdominal respiratory efforts. The pathogenesis of the central type of SAS is more complex. Narrowing of the upper airways may induce reflex inhibition of the respiratory center. Moreover, increased GH levels and, possibly, defects in the somatostatinergic pathways, may increase the ventilatory response of the respiratory center to carbon dioxide, thereby leading to respiratory arrest. In the mixed type of SAS, the phenomena underlying the other two forms coexist. Oxygen desaturation concomitant with the apneic episodes accounts for the frequent nocturnal wakening and diurnal drowsiness. Among the clinical correlates of SAS, arterial hypertension is of particular interest due to the close correlation existing between the two disorders. Sleep deprivation related to SAS seems per se to favor the appearance of hypertension. Moreover, short lasting hypoxemia may induce prolonged elevations of blood pressure, mediated by decreased endothelial generation of nitric oxide. Thus, since cardiovascular events are the main cause of mortality in patients with acromegaly, it is reasonable to hypothesize that SAS is involved in the reduced life span of these patients.

Cell proliferation in nasal respiratory epithelium of people exposed to urban pollution

The nasal passages are a common portal of entry and are a prime site for toxicant-induced pathology. Sustained increases in regenerative cell proliferation can be a significant driving force in chemical carcinogenesis. The atmosphere in Mexico City contains a complex mixture of air pollutants and its residents are exposed chronically and sequentially to numerous toxicants and potential carcinogens. We were concerned that exposure to Mexico City's atmosphere might induce cytotoxicity and increase nasal respiratory epithelial cell proliferation. Nasal biopsies were obtained for DNA cell cycle analysis from 195 volunteers. The control population consisted of 16 adults and 27 children that were residents in a Caribbean island with low pollution. The exposed Mexico City population consisted of 109 adults and 43 children. Sixty-one of the adult subjects were newly arrived in Mexico City and were followed for 25 days from their arrival. Control children, control adult and exposed Mexico City children all had similar percentages of cells in the replicative DNA synthesis phase (S phase) of the cell cycle (%S). A significant increase in %S in nasal epithelial cells was seen in exposed adult residents in Mexico City biopsied at three different dates compared with control adults. Newly arrived adults exhibited a control level of cell turnover at day 2 after coming to the city. However, at days 7, 14 and 25 they exhibited significant increases in %S. These data demonstrate an increased and sustained nasal cell turnover rate in the adult population observable in as little as 1 week of residence in Mexico City. This increase in cell proliferation is in agreement with other reports of induced pathological changes in the nasal passages of Mexico City dwellers. These observations suggest an increased potential risk factor of developing nasal neoplasms for residents of large cities with heavy pollution.

Subglottic injury, gastric juice, corticosteroids, and peptide growth factors in a porcine model

OBJECTIVES

To study the effects of mucosal injury, gastric juice, and corticosteroids and to determine the presence of peptide growth factors in the subglottic mucosa in a porcine model.

STUDY DESIGN

Prospective cohort animal study.

METHODS

In this model of subglottic injury, five groups (n = 5 each) of piglets were used. Injury was induced by electrocautery (acute), electrocautery plus repeated saline application (chronic), electrocautery plus repeated gastric juice application (chronic plus gastric juice), or repeated gastric juice application (gastric). Control piglets had normal saline applied repeatedly.

RESULTS

Histopathologic findings for the gastric juice group included basal cell hyperplasia (80%), squamous metaplasia (80%), and mucosal ulceration (40%). Control piglets showed squamous metaplasia (80%) but no basilar hyperplasia or ulceration. Immunohistochemistry detected peptide growth factors and epidermal growth factor receptor (EGFR) in all groups. Decreased staining was most frequent in the acute injury group. Quantitative reverse transcriptase polymerase chain reaction (RT-PCR) documented lower expression of EGFR in the gastric juice group (P = .01).

CONCLUSIONS

These findings suggest that peptide growth factors and EGFR are part of normal subglottic mucosal turnover. Noxious stimuli decrease production of these factors. Gastric juice had adverse effects documented by histopathology and molecular techniques.

In vitro generation of adult rat olfactory sensory neurons and regulation of maturation by coculture with CNS tissues

Olfactory sensory neurons (OSNs) are continually generated throughout life. Although previous studies have examined neurogenesis in olfactory cell cultures derived from embryonic or newborn rodents, we demonstrate neurogenesis in cell cultures derived from adult rat tissues. Dissociated cells taken from adult rat nasal mucosal tissues (ANM cells) were plated onto a feeder layer of newborn rat cortical glia (astrocytes) in serum-free conditions. Immature OSNs (stained for neuron-specific tubulin, NST) increased in number between 1 and 5 d in vitro (DIV) and in mass thereafter. Mature OSN (stained for olfactory marker protein, OMP) numbers decreased between 1 and 5 DIV, then increased over 5 DIV values by 12 and 15 DIV. Pulse labeling with [3H]thymidine confirmed in vitro neurogenesis. To determine whether the target cells for OSNs, olfactory bulb (OB) neurons, provide trophic support, dissociated newborn rat OB cells were cocultured with ANM cells on glia. This resulted in greater numbers of OMP-positive (OMP+) neurons after 9 DIV than ANM-alone cultures. This neurotrophic effect was not OB specific. Addition of newborn rat cerebellar and embryonic rat ventral mesencephalic cells to ANM cells also increased OMP+ neurons, whereas addition of newborn rat cortical cells or controls (purified glia or fibroblasts) did not. Changes in numbers of dopaminergic neurons (stained for tyrosine hydroxylase), present in OB and VM cultures, did not correlate with OMP+ neuronal increases. Thus, cultures of adult rat OSNs demonstrate neurogenesis, and trophic/maturation support is variably provided by CNS neurons (and not glia).

Epithelial cell proliferation in nasal polyps could be up-regulated by platelet-derived growth factor

The modifications of epithelial differentiation and proliferation observed in nasal polyps (NP) could be related to local secretion of growth factors, among which platelet-derived growth factor (PDGF) could play a key role. We therefore prospectively studied, by immunohistochemistry, proliferating cell nuclear antigen (PCNA, an S-phase cell marker), PDGF, and CD-68 (activated macrophages marker) expression in NP and inferior turbinate mucosa (NM) in 11 patients. Our data show that PCNA and PDGF expression are increased in NP epithelium, while CD-68 expression is increased in NP epithelium and lamina propria when compared to NM. Increased local PDGF secretion by numerous activated macrophages could therefore be involved in epithelial cell proliferation up-regulation in NP. PDGF could also be involved in the pathogenesis of NP via its connective tissue remodeling actions.

Platelet-derived growth factor in asthma

Platelet-derived growth factor (PDGF) controls cellular growth, migration, and differentiation. It is secreted by various cell types, including macrophages, and participates in tissue repair and epithelial regeneration. PDGF may therefore be involved in airway remodeling in asthma. This study compared the immunoreactivity of PDGF and its receptors (R alpha and R beta) in bronchial biopsies and the levels of PDGF in bronchoalveolar lavage (BAL) fluid of asthmatics and control subjects. Bronchial biopsies were done in a subsegmental bronchus of 11 asthmatics and 11 control subjects by flexible bronchoscope. PDGF AA and BB, and PDGF receptors R alpha and R beta were studied with monoclonal antibodies and revealed by immunoperoxidase staining. The percentage of subjects presenting positive staining with PDGFs and its receptors was studied in the epithelium and submucosa. PDGF AA, AB, and BB were measured in BAL fluid of 18 asthmatics and 10 controls by specific ELISA. In biopsies, there was no significant difference between asthmatics and controls for PDGF AA, BB, PDGF-R alpha and R beta (Fisher's exact test and Bonferroni's correction). Moreover, the levels of PDGF, AA, AB, and BB were similar in asthmatics and controls. This study does not support a role for PDGF in the repair processes of asthma.

Nasal congestion during the menstrual cycle

Oestrogens have been considered to cause nasal congestion during the menstrual cycle and during pregnancy. The aim of the present study was to evaluate the degree of nasal congestion during the menstrual cycle in healthy women. Nasal peak expiratory flow (nPEF) was measured and subjective nasal stuffiness was scored morning and evening by 27 women for 3 months and by 14 women for 6 months. During the menstrual days, when the serum oestrogen level is lowest, the morning nPEFs were significantly lower compared with the rest of the cycle (P = 0.0012). The difference was most pronounced for the second day of the cycle (P = 0.00034). The correlation between nPEFs and the subjective scores was high (R = 0.98), while the coefficient of variation within the series of three nPEF recordings was low (6.4%). It is concluded that the nasal obstruction experienced during menstruation cannot be explained by increased serum levels of oestrogen.

Secretion from gland and goblet cells in infected sinuses

The number of goblet cells in the normal mucosa in the paranasal sinuses is comparable to that in the nasal mucosa. There are relatively few mucosal glands in the sinuses. In recent years, the maxillary sinus of the rabbit has been used for experimental studies. After induced infections, the number of goblet cells increases. In pneumococcal sinusitis, the number reaches a peak after 3 weeks and then declines. In sinusitis induced by St. aureus and the anaerobic bacteria B. fragilis, the number is more progressive over time and persistent during 12 weeks. The number of glands shows no hyperplasia, but occasionally atypical glands can be found. In patients with chronic sinusitis, the number of goblet cells is usually not affected but the number of glands increases, and the glands usually have a pathological shape. A decreased ciliary beating frequency correlates well with an increase in number of goblet cells. However, 75% of patients with chronic sinusitis have a normal frequency. When performing studies in patients with sinusitis one should be aware of the dynamic course of the disease and the difficulty in evaluating single mucosal biopsies.