The Role of Oxidants and Antioxidants in Otitis Media with Effusion in Children

A Consolidated Understanding of the Contribution of Redox Dysregulation in the Development of Hearing Impairment

The etiology of hearing impairment is multifactorial, with contributions from both genetic and environmental factors. Although genetic studies have yielded valuable insights into the development and function of the auditory system, the contribution of gene products and their interaction with alternate environmental factors for the maintenance and development of auditory function requires further elaboration. In this review, we provide an overview of the current knowledge on the role of redox dysregulation as the converging factor between genetic and environmental factor-dependent development of hearing loss, with a focus on understanding the interaction of oxidative stress with the physical components of the peripheral auditory system in auditory disfunction. The potential involvement of molecular factors linked to auditory function in driving redox imbalance is an important promoter of the development of hearing loss over time.

Possible role of endoplasmic reticulum stress in the pathogenesis of chronic adenoiditis and adenoid hypertrophy: A prospective, parallel-group study

Background

Adenoid tissue is a first-line host defense secondary lymphoid organ, especially in childhood. The endoplasmic reticulum (ER) is required to maintain balanced cellular activity. With impaired ER functions, protein accumulation occurs, resulting in ER stress, which plays a role in the etiopathogenesis of many diseases.

Objective

We aimed to investigate the relationship between ER stress and adenoid tissue disorders, thereby elucidating the mechanisms of immunity-related diseases.

Methods

Fifty-four pediatric patients (>3 years old) who underwent adenoidectomy for chronic adenoiditis (CA) or adenoid hypertrophy (AH) were enrolled in this prospective, parallel-group clinical study. Adenoids were divided into two groups (CA or AH) based on their size and evaluated for ER stress pathway and apoptosis pathway markers by Real-time PCR and Western blot analysis.

Results

ER stress pathway markers significantly differed between the CA and AH groups. Children with CA had higher ER stress marker levels than the AH group (p < .001 for ATF-4, ATF-6, and GRP78, and p < .05 for EDEM1, CHOP, EIF2AK3, ERNI, and GRP94). Apoptosis pathway marker levels (BAX and BCL-2) were not different between groups.

Conclusions

ER stress contributes to the etiopathogenesis of adenoid tissue diseases and the pathogenesis of adenoid tissue disorders, which are part of the immune response. These results may guide the development of new and alternative treatments for immune system disorders.

Association of iron deficiency with chronic suppurative otitis media in adults

BACKGROUND

Chronic suppurative otitis media (CSOM) is a prevalent chronic inflammatory disease globally. Current research suggests a possible association between anaemia and the development of CSOM.

OBJECTIVES

The objective of this trial was to investigate the relationship between iron metabolism and chronic suppurative otitis media (CSOM) in adults aged 20-60 years.

MATERIALS AND METHODS

A consecutive sampling case-control study was used. The study participants were divided into a case group (42 children diagnosed with CSOM) and a control group (42 children with normal ears). Haemoglobin (Hb), Hematocrit (Hct), mean corpuscular volume of erythrocytes (MCV), serum iron level (SI), unsaturated iron-binding capacity (UIBC), total iron-binding capacity (TIBC), transferrin (TF), ferritin (Fer) were tested in all the participants, and the results were compared with the normal ranges of the World Health Organization (WHO). The comparative analysis of cases and controls was performed using the Fisher extract test, independence t-test, or Mann-Whitney U test. p-value <.05 was considered statistically significant for correlation.

RESULTS

There were 61 patients with CSOM and 61 controls included in the study. In the case group, 16 out of 61 patients (26.2%) had low ferritin levels and in the control group, 1 out of 61 patients (1.6%) had low ferritin levels (p < .001). In the case group, 6 (9.8%) of 61 patients had IDA, and in the control group, there were no patients with IDA among 61 patients (p = .027). There were significant differences in SI, UIBC, and Fer parameters between the groups.

CONCLUSIONS

In adult patients, the incidence of iron deficiency was higher in CSOM patients than in controls. Iron deficiency may be considered a potential risk factor for chronic suppurative otitis media, and serum iron parameters should be evaluated in these CSOM patients and further studies should be conducted to better understand the potential link between iron deficiency and CSOM.

Correlation between Serum Interleukin-17 level and Serum Reactive Oxygen Species levels among Children experiencing Otitis Media with Effusion

Introduction  The detection of inflammatory mediators in the serum of children with have otitis media with effusion (OME) and their correspondence with clinical considerations may enable the use of a modern nonsurgical curative treatment for OME.

Objective  To determine the relation between interleukin-17 (IL-17) serum level and reactive oxygen species (ROS) serum levels in children suffering from OME and to disclose if any variation occurs in the level of IL-17 Will affect the ROS and antioxidant equilibrium in the serum, which indicates the entire body's reaction to OME.

Methods  The present study was a case-control study. A total of 24 children experienced OME, and 24 healthy controls were recruited.

All participants in the study were subjected to a systematic clinical investigation including otoscopic, audiometric, and tympanometric examination. Also, venous blood samples were collected from all children to determine the levels of IL-17 and ROS.

Results  The mean ± standard deviation (SD) age ranges of the patients and the control group were 6.8 ± 2.7 and 6.2 ± 3.4 years, respectively. A stylistically significant difference in the levels of serum nitric oxide (NO), catalase (CT), myeloperoxidase (MPO), and malondialdehyde (MDA) ( p  < 0.05) was detected between OME and control patients. No significant difference was found in serum levels of superoxide dismutase (SOD) and glutathione peroxidase (GPX) between OME and control patients. The serum levels of MDA, NO, and MPO positively correlated with the serum levels of IL-17 in OME patients.

Conclusion  In the present study, there is a reasonable role of the IL-17 pathway in OME pathogenesis through an increase in ROS levels.

The Role of Manganese, Cadmium, Chromium and Selenium on Subjective Tinnitus

Elevated levels of heavy metals like cadmium (Cd) and manganese (Mn) are known to lead to oxidative damage-related oto-toxicity and decreased levels of chromium (Cr) and selenium (Se) are known to lead to oto-toxicity due to reduced anti-oxidant activity. The aim of the present study was to evaluate serum levels of Cd, Mn, Cr, and Se and their relationship with tinnitus. A total of 48 patients with tinnitus (Group 1) and 40 healthy controls (Group 2) were included in the study. All participants were applied audiology tests. Severity of tinnitus was measured with Tinnitus Severity Index Questionnaire (TSIQ) in group 1. Serum Mn, Cd, Cr, and Se measurements were done by using The Agilent ICP-MS system consisted of a 7700 coupled plasma mass spectrometry (ICP-MS). Serum Cd, Mn, and Cr levels were higher in group 1 and Se level was lower in group 1 than that of group 2. We may conclude that Cd, Mn, Cr, and Se levels could play an important role in etio-pathogenesis of tinnitus, and thereby supplementation or reduction of these elements could be considered as novel therapeutic goals.

Influence of a Polyherbal Mixture in Dairy Calves: Growth Performance and Gene Expression

A polyherbal feed mixture containing (Achyrantes aspera, Trachyspermum ammi, Citrullus colocynthis, Andrographis paniculata, and Azadirachta indica) was evaluated in growing calves through blood chemistry, blood biometry, and gene expression during the pre-ruminant to weaning period. Forty Holstein calves (initial BW 45.6 ± 3.2 kg; 22.8 ± 0.9 days post birth) from a dairy farm were randomly assigned to the following treatments: 0, 3, 4, and 5 g/d of a polyherbal mixture, dosed in colloid gels with gelatin. Calves were housed in individual outdoor boxes with ad libitum access to a 21.5% CP calf starter and water and fed individually with a mixture of milk and a non-medicated milk replacer (22% CP). Blood samples were collected on day 59 for blood chemistry, blood biometry, and gene expression analysis in leukocyte through microarray assays. Immunoglobulins were quantified by enzyme-linked immunosorbent assay. The animals treated with the polyherbal mixture showed a quadratic effect on final body weight, daily weight gain, final hip height, and final thoracic girth. The best performance results were obtained with a treatment dose of 4 g/d. The serum IgG increased linearly with the treatment doses. Gene set enrichment analysis of upregulated genes revealed that the three biological processes with higher fold change were tight junction, mucin type O-Glycan biosynthesis, and intestinal immune network for IgA production. Also, these upregulated genes influenced arachidonic acid metabolism, and pantothenate and CoA biosynthesis. Gene ontology enrichment analysis indicated that the pathways enriched were PELP1 estrogen receptor interacting protein pathways, nuclear receptors in lipid metabolism and toxicity, tight junction, ECM-receptor interaction, thyroid hormone signaling pathways, vascular smooth muscle contraction, ribosome function, glutamatergic synapse pathway, focal adhesion, Hippo, calcium, and MAPK signaling pathways.

Plasma Selenium and Cadmium Levels in Patients with Chronic Otitis Media in a Turkish Population and Their Relation to Inflammation Markers

Chronic otitis media (COM) is a multifactorial process, for which a clear etiology has not yet been established. The aims of the present study were to evaluate selenium (Se) and cadmium (Cd) levels in patients with COM and to analyze the correlation between Se and Cd with inflammation markers. The study population consisted of 88 participants: 45 healthy controls (group 1) and 43 patients with COM (group 2). Demographic data, Se, Cd, C-reactive protein (CRP), and white blood cell count (WBC) levels were all recorded. Se and Cd measurements were performed in a graphite furnace atomic absorption spectrophotometer (Perkin Elmer Analyst 800) using Zeeman background correction. The Se and Cd levels were compared between the groups and the correlation between Se and Cd with inflammation markers was analyzed. No statistically significant difference was determined between the groups in terms of demographic data (p > 0.05). CRP and WBC levels were significantly higher in group 2 than in group 1 (p < 0.05). Se levels were significantly lower in group 2 than in group 1, at 23.40 ± 12.08 μg/L vs. 37.31 ± 22.44 μg/L (p < 0.05). Cd levels were significantly higher in group 2 than in group 1, at 1.79 ± 1.63 μg/L vs. 0.68 ± 0.45 μg/L (p < 0.05). When all the cases were evaluated together, a statistically significant negative correlation was determined between Se and CRP (r = - 0.239, p = 0.013) and a positive correlation between Cd and CRP (r = 0.266, p = 0.006), WBC (r = 0.258, p = 0.008). Our results could propose that Se deficiency and Cd excess could play a crucial and additive role in the etiopathogenesis of COM. However, further investigations with larger numbers of patients are warranted to determine the exact role of these elements.

Genetic polymorphisms affecting antioxidant enzymes are present in tympanosclerosis patients

BACKGROUND

This study investigated genetic polymorphisms affecting the inducible nitric oxide synthase, superoxide dismutase and catalase enzymes in chronic otitis media patients with and without tympanosclerosis, and the role of genetic susceptibility in the disease aetiology.

METHODS

A total of 162 patients who underwent surgery for chronic otitis media were divided into two study groups: a tympanosclerosis group and a chronic otitis media group. A third, the control, group comprised 188 healthy volunteers. Venous blood samples were evaluated using reverse transcriptase polymerase chain reaction.

RESULTS

There was a significant difference in GG genotype distribution of the -277A>G polymorphism in the NOS2 gene between the tympanosclerosis and control groups (p T) polymorphism in the SOD2 gene (p > 0.05). There were significant differences in the TT genotype distribution of the -21A>T polymorphism in the CAT gene between the tympanosclerosis and control groups, and between the chronic otitis media and control groups (p < 0.05).

CONCLUSION

These results suggest that genetic predisposition may play a role in the aetiopathogenesis of tympanosclerosis.

The evaluation of oxidative stress in the serum and tissue specimens of patients with chronic otitis media

Objectives

To underline the effect of oxidative stress in chronic otitis media with and without cholesteatoma and to compare the oxidative stress values in the serum and tissue specimens in these two forms.

Methods

The study included a total of 75 individuals, 35 cases with chronic otitis media (COM; 16 females and 19 males) and a healthy control group of 40 cases (20 females and 20 males). The COM patient group was comprised of 18 patients with cholesteatoma and 17 patients without cholesteatoma. All patients underwent mastoidectomy. Serum specimens were taken prior to surgery and diseased tissue specimens from the ear were obtained during surgery from all patients. Only serum specimens were taken from the healthy control cases. The malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GHPx) were measured in the serum and tissue samples of the patient group and in the serum specimens of the control group.

Results

The age ranged from 14 to 48 years in the patient group (mean age, 20.4±12.2 years) and from 19 to 40 years in the control group (mean age, 26.4±4.64 years). When the serum values of all COM patients were compared with those of the control group, in the patient group MDA, which reflects lipid peroxidation, was found to be significantly higher (P<0.01) whereas the antioxidant enzymes SOD, CAT, and GHPx were found to be significantly lower (P<0.01). When the serum and tissue MDA, SOD, CAT, and GHPx values in patients with and without cholesteatoma were compared, no significant difference was found these parameters (P>0.01).

Conclusion

Although oxidative stress plays a role in the pathogenesis of COM with or without cholesteatoma, it may not reflect the severity of the disease. In patients with COM, the evaluation of only serum oxidative stress values without tissue evaluation may be sufficient for assessing oxidative stress.

Possible role of apoptosis in pathogenesis of adenoid hypertrophy and chronic adenoiditis: Prospective case-control study

OBJECTIVE

Apoptosis is a programmed cell death; it provides an important balance between lymphocytes in adenoid tissue. The aim of this study is to investigate the role of apoptosis in chronic adenoiditis and adenoid hypertrophy. This is the first study in the literature about apoptosis in adenoid hypertrophy and chronic adenoiditis.

METHODS

Prospective case-control study in a tertiary referral university hospital was conducted. 46 patients who had chronic adenoiditis and adenoid hypertrophy underwent adenoidectomy. Adenoids were evaluated for apoptosis and assembled into groups according to their size. Apoptotic cells were counted in three different microscopic fields and their average was taken for every microcompartment. As a result of immunohistochemical staining, specimens were compared for their apoptotic cell rate.

RESULTS

The difference in apoptosis of chronic adenoiditis and adenoid hypertrophy groups is statistically significant (p<0.05). The age 6 was used as a cut-off to compare apoptosis in adenoid tissue. The difference was not statistically significant for patients at and below 6 years of age; however, the difference was statistically significant for patients above 6 years of age. The comparison of apoptosis in microcompartments of adenoid tissue (intrafollicular, interfollicular, subepithelial and intraepithelial) between chronic adenoiditis and adenoid hypertrophy groups revealed significant differences for intrafollicular and intraepithelial areas, and insignificant differences for interfollicular and subepithelial areas.

CONCLUSION

Although apoptosis could not totally explain the pathogenesis of chronic adenoiditis and adenoid hypertrophy, it appeared to play an important role in it. Apoptosis functions to limit adenoid hypertrophy. Adenoid apoptosis appears to be age-dependent.

Serum paraoxonase and arylesterase activities in patients with chronic otitis media

OBJECTIVES

Paraoxonase-1 (PON1) prevents oxidative stress by inhibiting the oxidation of cell membrane lipids by the reactive oxygen species that form during acute and chronic inflammation. The aim of this study was to investigate serum PON1 activity and oxidative stress in patients with chronic otitis media (COM).

METHODS

Fifty consecutive patients with COM and 55 controls were enrolled in the present study. The patients were divided into two groups according to the presence of cholesteatoma. The serum PON1 arylesterase activities and lipid hydroperoxide (LOOH) levels were determined.

RESULTS

Serum paraoxonase and arylesterase activities were significantly lower in the COM patients than in the controls (P < 0.001 for all comparisons), whereas the LOOH levels were significantly higher (P < 0.001).

DISCUSSION

These results indicated that a lower level of PON1 activity was associated with an oxidant-antioxidant imbalance. In addition, decreased PON1 activity may play an important role in the pathophysiology of COM.

Apoptosis in chronic tonsillitis and tonsillar hypertrophy

OBJECTIVE

Chronic tonsillitis is the persistent inflammation of the tonsillar tissue that occurs due to recurrent, acute or subclinical infection. The recurrent and chronic inflammation of palatine tonsils sometimes results in hypertrophy. Apoptosis provides an important balance between lymphocytes in tonsillar lymphoid tissue. The aim of this study is to investigate the apoptosis in tonsillar diseases.

METHODS

43 patients with chronic tonsilitis and tonsillar hypertrophy underwent tonsillectomy. The specimens were examined immunohistochemically for apoptosis. Tonsils were assembled into groups according to their size. Specimens were compared for their apoptotic cell count.

RESULTS

The apoptosis difference between the tonsil size groups is not statistically significant (p>0.05). However, when the study group was divided into two at age 6, the difference was not statistically significant for patients at and below 6 years of age; but, the difference was statistically significant for patients above 6 years of age (p<0.05). The comparison of apoptosis in microcompartments of tonsil tissue (intrafollicular, interfollicular, subepithelial and intraepithelial) between tonsil size stages and between chronic tonsillitis and tonsillar hypertrophy groups revealed no statistical significance (p>0.05). There was a statistically significant positive correlation between intrafollicular and interfollicular, interfollicular and intraepithelial & subepithelial and intraepithelial areas (p<0.05).

CONCLUSIONS

In the light of these findings, it was concluded that apoptosis played a role in the tonsillar hypertrophy and atrophy. Apoptosis functioned to balance lymphocyte proliferation in tonsil tissue. The association of apoptosis with tonsillar hypertrophy seemed to be age-dependent.

Middle ear inflammation of rat induced by urban particles

OBJECTIVE

The aim of this study was to evaluate the histologic change of middle ear mucosa and the expression levels of epithelial sodium channel (ENaC) subunits and mucin production genes, after the injection of urban particulate matter (UPM) into the middle ear cavity of rats.

METHODS

Fifty pathogen-free, male Sprague Dawley rats were assigned to the study. Transtympanic injection of UPM solution (300μg/ml, 50μl) was made into the middle ear cavity of rats. Rats were sacrificed at day 1 (group1); day 3 (group2); day 5 (group3); and day 14 (group4) after the procedure. The expression levels of ENaC subunits (α, β and γ) and mucin producing genes (MUC5AC and MUC5B) were analyzed using semi-quantitative real-time reverse transcriptase-polymerase chain reaction. Thickness of middle ear mucosa was measured and analyzed.

RESULT

After transtympanic injection, the thickness of middle ear mucosa increased significantly on day 1, 3 and 5 (p<0.05) and was normalized on day 14, compared to the control group. Inflammatory changes observed in the middle ear mucosa were subepithelial widening, inflammatory cell infiltration and vascular space widening on day 1, 3 and 5. These changes had reverted to normal on day 14. The level of ENaC-α expression decreased 0.60 fold on day 1 (p<0.05), but was normalized thereafter. The level of ENaC-β and γ decreased 0.39 and 0.27 fold, respectively, on day 1, was normalized on days 3 and 5, and increased 2.30 and 2.47 fold on day 14, respectively (p<0.05). The level of MUC5AC expression increased 1.97-fold on day 1 (p<0.05) and 2.58-fold on day 5 (p<0.05), but was normalized on day 14. The level of MUC5B expression increased 5.4-fold on day 1, 3.14-fold on day 3, 3.85-fold on day 5, and 2.46-fold on day 14, respectively (p<0.05).

CONCLUSION

Transtympanic injection of UPM solution into the middle ear cavity of rat induced a characteristic inflammatory response and altered gene expression related with inflammation and mucin production. These findings provide a useful clue for the understanding of how air pollutants, particularly UPM, contribute to the development of otitis media.

Advanced oxidation protein product level in children with chronic otitis media with effusion

OBJECTIVE

To determine the level of advanced oxidation protein products (AOPPs) in children with chronic otitis media with effusion (COME), in an effort to elucidate the multifactorial etiology of this disease.

METHODS

This study involved 25 COME patients and 30 healthy children (control group) recruited from the Ear, Nose and Throat (ENT) and Pediatric Departments, respectively, of the Haseki Research and Training Hospital. In the COME group, blood samples were collected before a middle ear operation, and middle ear fluid was sampled during the operation. Blood samples were also obtained from the control subjects. AOPP levels in the plasma and effusion fluid were measured by the spectrophotometric method.

RESULTS

In the COME group, the mean AOPP levels in plasma and effusion fluid were 168.08 μmol/l and 412.75 μmol/l, respectively. In the control group, the mean plasma AOPP level was 141.54 μmol/l. The plasma AOPP levels did not significantly differ between the COME and control groups (p>0.05). In the COME group, however, the effusion fluid AOPP level (412.75 ± 204.54 μmol/l) was significantly higher than the plasma AOPP level (168.08 ± 68.45 μmol/l; p<0.01).

CONCLUSION

We found that AOPP levels were elevated in the effusion fluid, but not in the plasma, of COME patients. Thus, COME was associated with protein oxidation abnormalities. Oxidative stress may play a role in the etiopathogenesis of COME, and AOPPs may be used as markers of oxidative stress; however, further studies are required to confirm these findings.

Is there a relationship between serum levels of vitamin a, vitamin e, copper and zinc and otitis media with effusion in children?

The aim of this study is to determine whether the serum levels of vitamin A, vitamin E, copper and zinc have a role in the development of otitis media with effusion (OME) in childhood. This prospective study was conducted between February 2010 and February 2011 at a tertiary Otorhinolaryngoloy Clinic. There were 113 subjects and subdivided into three groups. Group 1 consisted of 44 patients who underwent adenoidectomy with ventilation tube placement due to OME. Group 2 consisted of 43 patients underwent adenoidectomy alone and group 3,called control group, included 26 healthy children. Serum values of vitamin A, vitamin E, copper and zinc were measured preoperatively. Comparison of the patient groups showed that group 1 patients had significantly lower serum zinc levels than group 2 patients (p = 0.002), although differences between both patients groups and controls were not significant. We found that the differences among the three groups in terms of serum levels of vitamin A, vitamin E and copper were not statistically significant (p > 0.05). The results of this study showed that serum levels of vitamin A, vitamin E and copper may not play a role on development of OME. We postulated that high serum zinc status may have the preventive effect in the predisposition to OME which may related to adenoid hyperplasia.

Serum myeloperoxidase activity, total antioxidant capacity and nitric oxide levels in patients with chronic otitis media

It has been suggested that oxidative stress may play an important role in the pathogenesis of chronic otitis media (COM), but the role of oxidative stress in the pathogenesis of COM has not yet been fully explored. Therefore, the aim of this study was to investigate serum myeloperoxidase (MPO) activity, 4-hydroxynonenal (4-HNE), malondialdehyde (MDA), total antioxidant capacity (TAC) and nitric oxide (NO) in patients with COM. Sixty-one patients with COM and 30 controls were enrolled in the present study. Patients were divided into two groups according to the presence (n = 21) or absence (n = 40) of cholesteatoma. Serum MPO activity and 4-HNE, MDA and NO levels were significantly higher in patients with COM than controls (for all, p < 0.001), while TAC levels were significantly lower (for all, p < 0.001). Serum MPO activity and MDA, 4-HNE and NO levels were significantly higher in patients with cholesteatoma than in those without cholesteatoma, while TAC levels were significantly lower; but the difference between groups was not statistically significant (p > 0.05). Increased oxidative stress seems to be associated with decreased antioxidant levels in patients with COM. Thus, increased oxidative stress may play a role in the pathogenesis of COM. It is believed that the administration of antioxidant vitamins such as A, C and E may be useful in preventing and treating COM.

Effect of caffeic acid phenethyl ester (CAPE) on H₂O₂ induced oxidative and inflammatory responses in human middle ear epithelial cells

OBJECTIVE

Acute otitis media (OM) is a common pediatric disease. Recent research into the pathogenesis of OM has focused on oxidative damage, induced by oxygen free radicals, to the middle ear mucosa along with inflammation. Caffeic acid phenethyl ester (CAPE) is a biologically active ingredient of propolis honey bees, with antioxidative and anti-inflammatory activities. The effect of CAPE on hydrogen peroxide (H(2)O(2))-induced inflammatory and oxidative reactions in the middle ear is still not known. The aim of this study was to evaluate the anti-inflammatory and antioxidative effects of CAPE on cultured human middle ear epithelial cells (HMEECs).

METHODS

The inflammatory injury of H(2)O(2) and the anti-inflammatory effect of CAPE were determined by measuring levels of pro-inflammatory cytokines (tumor necrosis factor (TNF)-α and COX-2) with real-time reverse transcription polymerase chain reaction and Western blot analysis. Oxidative stress induced by H(2)O(2) and antioxidative effects of CAPE were evaluated directly by reactive oxygen species (ROS) production using flow cytometric analysis of 5-(and-6)-chloromethyl-2',7'-dichlorodihydrofluorescein diacetate, acetyl ester (CM-H(2)DCFDA), and indirectly by the expression of superoxide dismutase (SOD) using Western blot analysis. The effect of CAPE was compared with N-acetyl cysteine (NAC) which has well-known antioxidative and anti-inflammatory effects.

RESULTS

CAPE significantly inhibited H(2)O(2)-induced upregulation of TNF-α and COX-2 expression in a dose and time dependent manner. ROS accumulation induced by H(2)O(2) stimulation was decreased by CAPE pretreatment. Induced SOD expression after H(2)O(2) stimulation was diminished by CAPE pretreatment. The anti-inflammatory and antioxidative effects of CAPE were similar to those of NAC.

CONCLUSIONS

These findings suggest that inflammation induced by H(2)O(2) can be inhibited by CAPE via inhibition of the expression of pro-inflammatory cytokines such as TNF-α and COX-2. Furthermore, CAPE has antioxidative effects, which decreases the need for endogenous SOD expression.

Antioxidant role of selenium in rats with experimental acute otitis media

The aim of this prospective experimental animal study was to determine whether selenium had a protective effect on oxidative stress in rats with acute otitis media, by measuring the alterations of antioxidant parameters and lipid peroxidation on days 4 and 10 after inoculation into the middle ear. Streptococcus pneumoniae was inoculated into the middle ear cavities of 32 rats in animal laboratory of a tertiary medical center. Group 1 served as the control group and the animals were administered 1.5 ml/day saline. Group 2 received 0.2 mg/kg/day oral selenium for 10 days. The blood samples of each group were obtained on post-inoculation days 4 and 10. The levels of thiobarbituric acid reactive substances, albumin, total sulphydryl, superoxide dismutase and glutathione peroxidase were investigated. Day 10 level of thiobarbituric acid reactive substance in group 2 was lower than the day 4 level of the same substance in the control group. Although glutathione peroxidase and superoxide dismutase levels significantly decreased starting from 4th day until 10th day in group 1, their levels increased in group 2. Day 10 levels of albumin and total sulphydryl in group 1 were significantly higher than day 4 levels in group 2. We found that selenium supplementation for 10 days decreased thiobarbituric acid reactive substances and increased glutathione peroxidase and superoxide dismutase levels when compared to the control group. We believe that selenium supplementation may be beneficial to prevent the clinical sequelae and recurrence of otitis media.

Diagnostic and Therapeutic Significance of the Oxidative Stress Parameters in Children

Pharmacotherapy of pediatric diseases represents a major challenge considering that the majority of medicines in everyday practice have not been pediatrically evaluated. The efficacy of therapy depends to a large extent on the knowledge of pathophysiological processes in the children organism at different ages. Therefore, research in that direction is of the utmost importance. An imbalance in the production of free oxygen/nitrogen species and parameters of antioxidative protection is a significant factor in many diseases (e.g. heart failure, pulmonary hypertension, asthma, neonatal sepsis, cancer etc.) in children of different age groups. Reactive oxygen/nitrogen species serve as cell signaling molecules for normal biologic processes. An increase in their generation can cause damages which can disrupt normal physiological cellular processes and eventually cause cell death. This review outlines the previous assessments of oxidative stress parameters in children of different ages for some diseases. Also, the potential diagnostic and therapeutic possibilities for the oxydative stress parameters in children have been considered.

The imbalance of enzymatic antioxidants in cholesteatoma

CONCLUSION

Depletion of enzymatic antioxidants was observed in cholesteatoma. However, a relationship between activity of enzymatic antioxidants and the extent of bone erosion was not found.

OBJECTIVES

To measure the level of major enzymatic antioxidants in cholesteatoma, and to investigate the relationship between the level of enzymatic antioxidants and the extent of bone erosion.

PATIENTS AND METHODS

The cholesteatoma and skin samples were obtained during otologic surgeries. All cases were grouped according to the number of bone erosion sites. Samples were examined biochemically and the levels of enzymatic antioxidants were measured. The results were analyzed statistically.

RESULTS

Thirteen patients were included in the study. The mean level of superoxide dismutase in cholesteatoma and skin was 45.87 U/mg and 71.04 U/mg, respectively. When the catalase level was evaluated, the mean level was 5.04 U/g in cholesteatoma and 11.62 U/g in skin. The mean level of glutathione peroxidase in cholesteatoma and skin was 12.13 IU/g and 236.74 IU/g, respectively. All the results of cholesteatoma and skin samples were compared through non-parametric tests and statistically significant differences were found. However, a statistically significant difference between the levels of enzymatic antioxidants and the extent of bone erosion was not observed.

The effect of passive smoking and breast feeding on serum antioxidant vitamin (A, C, E) levels in infants

AIM

Toxic substances in tobacco smoke are known to have negative effects on the antioxidant capacity of human body. In order to investigate the effect of passive smoking on serum antioxidant levels in infants, serum vitamin A, E, C levels and urinary cotinine/creatinine levels were measured in 254 infants at the age of 6 months.

METHODS

The information about infants' nutrition and exposure to tobacco smoke was obtained from the mothers by the help of a questionnaire. The infants were grouped according to both smoking status of mother and urinary cotinine/creatinine levels.

RESULTS

The mean serum vitamin A, C and E levels of infants of smoking mothers were significantly lower than those of non-smoking mothers (p < 0.05). Vitamin A, E and C levels were negatively correlated with urinary cotinine/creatinine levels (p < 0.05, r: -0.61, -0.42, -0.53, respectively). Multivariate analysis revealed independent factors determining the serum vitamin A, E and C levels of infants as maternal smoking and breast feeding (p < 0.05).

CONCLUSION

Tobacco smoke exposure of infants significantly decreases their serum antioxidant vitamin A, C and E levels. However, breast feeding may help to prevent the decrement of antioxidant vitamin levels of passive smoking infants.

The role of retinol in the etiology and outcome of suppurative otitis media

Vitamin A deficiency is still a serious public health problem affecting an estimated 127 million preschool children. The resulting immunological dysfunctions lead to increased risks of respiratory tract infections, diarrhoeal diseases and blindness, among others. The aim of this study is to determine the significance of the role of serum retinol in the etiology of acute suppurative otitis media (ASOM) and its chronicity (CSOM). In a prospective follow-up of patients with ASOM for 6-9 months, serum retinol determination was done using the high performance liquid chromatography. Participants comprised 358 ASOM and 52 control subjects. Six-month follow-up was achieved in 264 subjects (74%); of these, there was persistence of otorrhoea (CSOM) in 116, while 148 had resolved ASOM. Of the 264 subjects, 146 were males and 118 were females, between the ages of 6 months and 9 years and a mean of 7 years (SD = 2.32), whereas the control subjects comprised 29 males and 22 females, between the ages of 6 months and 11 years and a mean of 7.8 years (SD = 3.6). The range of serum retinol in the ASOM subjects was 1.63-2.64 microg/L, mean of 1.53 microg/L, median value of 2.61 microg/L and (SD = 0.16). Among control subjects, the range was 2.5-2.8 microg/L, mean of 2.58 microg/L and median value of 2.61 microg/L (SD = 0.14) (Table 1). The range of serum retinol in the resolved ASOM subjects was 1.61-2.63 microg/L, mean of 2.07 microg/L and median value of 2.09 microg/L (SD = 0.16) while the CSOM subjects ranged between 0.8-2.86 microg/L, mean of 1.58 microg/L and median value of 1.28 microg/L, (SD = 0.48) (Table 2). Univariate analysis using unpaired t test to compare the mean serum retinol revealed significant difference between ASOM and control (P = 0.0000) and between resolved ASOM and CSOM (P = 0.0000). In conclusion, hyporetinolaemia was a significant etiological factor in the etiology ASOM and CSOM, suggesting retinol supplementation as one strategy in control of SOM.

A comprehensive evaluation of the enzymatic and nonenzymatic antioxidant systems in childhood asthma

BACKGROUND

Even though there is ample evidence on the oxidative stress in asthma, there is limited information on the antioxidant defense systems.

OBJECTIVES

To conduct a comprehensive evaluation of various components of both enzymatic and nonenzymatic antioxidants in a large group of children with asthma.

METHODS

A total of 164 children with mild asthma and 173 healthy children were included in the study. Levels of the enzymes glutathione peroxidase and superoxide dismutase were measured by using ELISA, whereas reduced glutathione, ascorbic acid, alpha-tocopherol, lycopene, beta-carotene, amino acids participating in glutathione synthesis, and amino acids susceptible to oxidation were measured by HPLC. All comparisons were adjusted for atopy, body mass index, smoke exposure, and pet ownership.

RESULTS

Levels of the enzymes glutathione peroxidase and superoxide dismutase and of the nonenzymatic components of the antioxidant system including reduced glutathione, ascorbic acid, alpha-tocopherol, lycopene, and beta-carotene were significantly lower in children with asthma compared with healthy controls (P < .001 for each). Of the amino acids contributing to glutathione synthesis, glycine and glutamine were significantly lower in children with asthma (P < .001). The majority of the amino acid susceptible to oxidative stress displayed lower levels in children with asthma (P < .05).

CONCLUSION

Childhood asthma is associated with significant decreases in various components of both enzymatic and nonenzymatic antioxidant defenses.

Up-Regulation of MUC5AC and MUC5B Mucin Genes in Nasopharyngeal Respiratory Mucosa and Selective Up-Regulation of MUC5B in Middle Ear in Pediatric Otitis Media with Effusion

OBJECTIVES

Mucins are the major component responsible for the gel-like properties of mucus secretion. Currently, little is known about the regulation of mucins in otitis media with effusion (OME). We investigated the expression of MUC5AC and MUC5B mucin gene messenger (m)RNAs in middle ear effusions as well as in tissue biopsies of the respiratory mucosa of the nasopharynx by means of reverse-transcription polymerase chain reaction (RT-PCR).

STUDY DESIGN

A prospective, controlled, clinical trial.

METHODS

The study group consisted of 25 children with a diagnosis of OME who were to undergo bilateral ventilation tube insertion with adenoidectomy. A sample of middle ear effusion (n = 50) as well as tissue biopsy from nasopharyngeal respiratory mucosa (n = 25) were obtained from each patient. For the nasopharyngeal mucosal biopsies, two control groups were made up from 30 children with healthy ears who underwent tonsillectomy +/- adenoidectomy operation; control A, 15 children with adenoid hypertrophy, and control B, 15 children with healthy nasopharynx. RNAs were extracted from effusion and tissue samples, and semiquantitative RT-PCR was performed for MUC5AC and MUC5B to investigate their expression.

RESULTS

In the middle ear effusions, MUC5B mRNA expression was detected in 48 (96%), whereas MUC5AC mRNA was detected in 8 (16%). On semiquantitative analysis, MUC5AC/glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and MUC5B/GAPDH mRNA ratios in the study group were significantly increased compared with those in both control groups (P < .05).

CONCLUSIONS

The results suggest that the middle ear has a unique mucin gene expression pattern when compared with that of the nasopharynx. Up-regulation of MUC5B in the ear may play an important role in the pathogenesis of middle ear effusions.