Serum levels of antioxidant vitamins, copper, zinc and magnesium in children with chronic rhinosinusitis

Role of Magnesium in the Intensive Care Unit and Immunomodulation: A Literature Review

Both the role and the importance of magnesium in clinical practice have grown considerably in recent years. Emerging evidence suggests an association between loss of magnesium homeostasis and increased mortality in the critical care setting. The underlying mechanism is still unclear, but an increasing number of in vivo and in vitro studies on magnesium's immunomodulating capabilities may shed some light on the matter. This review aims to discuss the evidence behind magnesium homeostasis in critically ill patients, and its link with intensive care unit mortality via a likely magnesium-induced dysregulation of the immune response. The underlying pathogenetic mechanisms, and their implications for clinical outcomes, are discussed. The available evidence strongly supports the crucial role of magnesium in immune system regulation and inflammatory response. The loss of magnesium homeostasis has been associated with an elevated risk of bacterial infections, exacerbated sepsis progression, and detrimental effects on the cardiac, respiratory, neurological, and renal systems, ultimately leading to increased mortality. However, magnesium supplementation has been shown to be beneficial in these conditions, highlighting the importance of maintaining adequate magnesium levels in the intensive care setting.

Retinoic acid promotes fibrinolysis and may regulate polyp formation

BACKGROUND

Patients with aspirin-exacerbated respiratory disease (AERD) regularly exhibit severe nasal polyposis. Studies suggest that chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by excessive fibrin deposition associated with a profound decrease in epithelial tissue plasminogen activator (tPA). Retinoids, including vitamin A and its active metabolite retinoic acid (RA), are necessary for maintaining epithelial function and well-known inducers of tPA in endothelial cells.

OBJECTIVES

This study sought to determine whether endogenous retinoids are involved in NP pathophysiology and disease severity in patients with CRSwNP and AERD.

METHODS

NP tissue was collected from patients with AERD or CRSwNP, and concentrations of retinoids and fibrinolysis markers were measured using ELISA. Normal human bronchial epithelial cells were stimulated alone or in combination with RA and IL-13 for 24 hours.

RESULTS

This study observed lower retinoid levels in nasal polyps of patients with AERD than those with CRSwNP or healthy controls (P < .01). Levels of the fibrin-breakdown product d-dimer were the lowest in AERD polyps (P < .01), which is consistent with lower tPA expression (P < .01). In vitro, all-trans RA upregulated tPA levels in normal human bronchial epithelial cells by 15-fold and reversed the IL-13-induced attenuation of tPA expression in cultured cells (P < .01).

CONCLUSIONS

RA, a potent inducer of epithelial tPA in vitro, is reduced in tissue from patients with AERD, a finding that may potentially contribute to decreased levels of tPA and fibrinolysis in AERD. RA can induce tPA in epithelial cells and can reverse IL-13-induced tPA suppression in vitro, suggesting the potential utility of RA in treating patients with CRSwNP and/or AERD.

Thiol-disulfide balance and trace element levels in patients with seasonal allergic rhinitis

Background

The prevalence of allergic diseases is gradually increasing worldwide. The most common such allergic disease is allergic rhinitis (AR).

Objective

The present study investigated the possible relationship between seasonal AR and the thiol-disulfide balance and zinc and copper levels in adult individuals.

Study Design and Methods

130 male and female adults were included in the study. The participants' serum thiol-disulfide balance and zinc and copper levels were measured spectrophotometrically using commercial kits. Statistical significance was accepted as p < 0.05 between the groups.

Results

The serum copper (p = 0.001), native thiol (p = 0.006), reduced thiol (p < 0.001), and thiol oxidation reduction ratio (p < 0.001) levels were significantly lower in the seasonal AR group than in the control group.

Conclusion

In AR patients, the low level of copper, which is an important trace element, the deterioration of the thiol-disulfide balance, which represents a unique indicator of the oxidant-antioxidant balance, the increased disulfide level caused by oxidative stress, and the decreased native thiol level can all serve as important biochemical markers.

A follow-up study of mucociliary clearance and trace element and mineral status in children with chronic rhinosinusitis before and three months after endoscopic sinus surgery

BACKGROUND

The existing data demonstrate the potential role of trace elements in nasal mucociliary clearance, although the association between trace element and mineral status and ciliary function in children with chronic rhinosinusitis is insufficiently studied. Therefore, the objective of the present study is evaluation of trace element and mineral status and mucociliary function in pediatric CRS patients before and after functional endoscopic sinus surgery.

METHODS

The present study involved 30 children with chronic rhinosinusitis without nasal polyps. During this follow-up the patients were examined preoperatively (point 0), underwent functional endoscopic sinus surgery, and were repeatedly examined at three months postoperatively (point 1). At both points the patients were subjected to quality-of-life assessment using SNOT-20 questionnaire; endoscopic and computer tomography examination of the nasal sinuses; evaluation of ciliary function and mucosal cytology using high-speed videomicroscopy; assessment of blood count and inflammatory markers; as well as analysis of trace element and mineral levels in whole blood, serum, and hair using inductively-coupled plasma mass-spectrometry.

RESULTS

The obtained data demonstrate that endoscopic sinus surgery significantly improved sinonasal pathology in children with chronic rhinosinusitis, as evidenced by significantly reduced Lund-Mackay, Lund-Kennedy, and SNOT-20 scores. At the same time, no significant improvement of ciliary functions or mucosal cytology was observed postoperatively. Trace element status assessment demonstrated that postoperative serum Zn, whole blood Mg and Cu were significantly lower as compared to preoperative values. In contrast, serum Mn and Cr, as well as whole blood Cr and hair Se were characterized by a significant increase at three months postoperatively. Multiple linear regression analysis demonstrated that serum Zn is significantly associated with the number of ciliated cells and cell viability, whereas serum Mn and whole blood Cu concentrations are inversely associated with cell viability and ciliary length, respectively. Hair Se was found to be associated with the number of neutrophils in the mucosa biopsy.

CONCLUSION

Redistribution of trace elements and minerals may at least partially mediate prolonged recovery of mucosal ciliary function in children with chronic rhinosinusitis in three months after functional sinus surgery, although the particular mechanisms of these alterations in trace element levels are to be discovered.

Serum, Whole Blood, Hair, and Mucosal Essential Trace Element and Mineral Levels in Children with Verified Chronic Rhinosinusitis Undergoing Functional Endoscopic Sinus Surgery

The objective of the present study was to assess hair, serum, whole blood, and excised tissue essential element content in children with chronic rhinosinusitis (CRS). Eighty-eight children with chronic rhinosinusitis and 66 healthy controls were enrolled in the present study. Evaluation of endoscopic Lund-Kennedy and computed tomography Lund-Mackay scores, as well as tissue sampling, was performed only in children with chronic rhinosinusitis. Assessment of Sino-Nasal Outcome Test-20 (SNOT-20) scores was performed in both cases and controls. Hair, whole blood, blood serum, and excised mucosal tissue (only in patients) analysis was performed using inductively coupled argon plasma mass-spectrometry. The obtained data demonstrate that whole blood Ca, Mg, Se, and Zn, as well as hair Ca, Cu, Mg, and Zn levels in the examined patients were significantly lower as compared with the control values. Only serum Zn concentration in children with CRS exceeded the respective control values, whereas serum Cu levels only tended to decrease in CRS. In turn, hair Fe content in children with CRS exceeded that in healthy controls. Regression analysis demonstrate that hair Ca levels, as well as whole blood Ca, Se, and Zn concentrations, were considered as negative predictors, whereas increased hair iron level was significantly directly associated with CRS. Significant associations between hair, serum, whole blood, and tissue element levels and Lund-Kennedy and Lund-Mackay scores were also revealed. Generally, the obtained data demonstrate that chronic rhinosinusitis is associated with impaired essential metal levels in pediatric patients with chronic rhinosinusitis. The observed alterations may contribute to CRS pathogenesis through modulation of mucociliary clearance, immunity, inflammatory response, and redox environment.

Nutritional immunity: the impact of metals on lung immune cells and the airway microbiome during chronic respiratory disease

Nutritional immunity is the sequestration of bioavailable trace metals such as iron, zinc and copper by the host to limit pathogenicity by invading microorganisms. As one of the most conserved activities of the innate immune system, limiting the availability of free trace metals by cells of the immune system serves not only to conceal these vital nutrients from invading bacteria but also operates to tightly regulate host immune cell responses and function. In the setting of chronic lung disease, the regulation of trace metals by the host is often disrupted, leading to the altered availability of these nutrients to commensal and invading opportunistic pathogenic microbes. Similarly, alterations in the uptake, secretion, turnover and redox activity of these vitally important metals has significant repercussions for immune cell function including the response to and resolution of infection. This review will discuss the intricate role of nutritional immunity in host immune cells of the lung and how changes in this fundamental process as a result of chronic lung disease may alter the airway microbiome, disease progression and the response to infection.

Role of intracellular zinc in molecular and cellular function in allergic inflammatory diseases

Zinc is an essential micronutrient in human body and a vital cofactor for the function of numerous proteins encoded by the human genome. Zinc has a critical role in maintaining many biochemical and physiological processes at the molecular, cellular, and multiple organ and systemic levels. The alteration of zinc homeostasis causes dysfunction of many organs and systems. In the immune system, zinc regulates the differentiation, proliferation and function of inflammatory cells, including T cells, eosinophils, and B cells, by modifying several signaling pathways such as NFκB signaling pathways and TCR signals. An adequate zinc level is essential for proper immune responses and decreased zinc levels were reported in many allergic inflammatory diseases, including atopic dermatitis, bronchial asthma, and chronic rhinosinusitis. Decreased zinc levels often enhance inflammatory activation. On the other hand, the inflammatory conditions alter the intracellular homeostasis of zinc, often decreasing zinc levels. These findings implied that there could be a vicious cycle between zinc deficiency and inflammatory conditions. In this review, we present recent evidence on the involvement of zinc in atopic dermatitis, bronchial asthma, and chronic rhinosinusitis, with insights into the involvement of zinc in the underlying molecular and cellular mechanisms related to these allergic inflammatory diseases.

Metallothionein-3 is a clinical biomarker for tissue zinc levels in nasal mucosa

OBJECTIVE

Recently, depleted tissue zinc levels were found in nasal mucosa from patients with chronic rhinosinusitis (CRS) in correlation with tissue eosinophilia, however, no clinical biomarkers for tissue zinc levels have been identified. Metallothionein-3 (MT3) is an intracellular zinc chelator and previous data showed MT3 mRNA levels to be reduced in CRS patients with nasal polyps (CRSwNP). In this study, we examined the correlation between MT3 expression and zinc levels in nasal mucosa and primary human nasal epithelial cells (HNECs) to investigate whether MT3 could be a clinical biomarker for tissue zinc levels.

METHOD

Tissue was harvested from 36 patients and mounted on tissue micro-array (TMA) slides. MT3 expression and tissue zinc fluorescence intensity were measured at different areas within the mucosa (surface epithelium and lamina propria) and compared between controls, CRSwNP and CRS without nasal polyps (CRSsNP) patients. MT3 mRNA and protein expression were examined in zinc-depleted HNECs by qPCR and immunofluorescence microscopy.

RESULTS

MT3 expression in CRSwNP was significantly decreased in both surface epithelium (p<0.001 to controls) and lamina propria (p = 0.0491 to controls). There was a significant positive correlation between tissue zinc levels and MT3 expression in nasal mucosa (r = 0.45, p = 0.007). In zinc-deplete HNECs, MT3 expression was significantly decreased at mRNA (p = 0.02) and protein level (p<0.01). There was a significant positive correlation between tissue zinc levels and MT3 expression within individual HNECs (r = 0.59, p<0.001).

CONCLUSIONS

MT3 expression reflects intramucosal zinc levels in both nasal mucosa and HNECs indicating MT3 could be used as a clinical biomarker for monitoring intracellular zinc levels in the nasal mucosa.

Serum levels of superoxide dismutases in patients with benign paroxysmal positional vertigo

Objective: To investigate the possible role of superoxide dismutases (SODs) in the development of benign paroxysmal positional vertigo (BPPV) and recurrence events in a 1-year follow-up study.

Methods: This was a prospective one-center study. A total of 204 patients with BPPV and 120 age-and sex matched healthy subjects were included. The levels of SOD between patients and control cases were compared. The levels of SOD between posterior semicircular canal (PSC) and horizontal semicircular canal (HSC) were also compared. In the 1-year follow-up, recurrence events were confirmed. The influence of SOD levels on BPPV and recurrent BPPV were performed by binary logistic regression analysis.

Results: The serum levels of SOD in patients with BPPV were lower than in those control cases (P<0.001). Levels of SOD did not differ in patients with PSC and HSC (P=0.42). As a categorical variable, for per interquartile range (IQR) increment of serum level of SOD, the unadjusted and adjusted risks of BPPV would be decreased by 72% (with the odds ratio [OR] of 0.28 [95% confidence interval (CI): 0.21–0.37], P<0.001) and 43% (0.57 [0.42–0.69], P<0.001), respectively. Recurrent attacks of BPPV were reported in 50 patients (24.5%). Patients with recurrent BPPV had lower levels of SOD than in patients without (P<0.001). For per IQR increment of serum level of SOD, the unadjusted and adjusted risks of BPPV would be decreased by 51% (with the OR of 0.49 [95% CI: 0.36–0.68], P<0.001) and 24% (0.76 [0.60–0.83], P<0.001), respectively.

Conclusion: Reduced serum levels of SOD were associated with higher risk of BPPV and BPPV recurrence events.

Mucociliary transport as a link between chronic rhinosinusitis and trace element dysbalance

Chronis rhinosinusitis is considered as a widespread public health issue with a prevalence of 10%. The disease significantly reduces quality of life and increases the risk of cardiovascular diseases as well as certain forms of cancer. Alteration of mucociliary clearance frequently observed in the patients and plays a significant role in disease pathogenesis. Certain studies have demonstrated that patients with chronic rhinosinusitis are characterized by significant reduction of essential trace elements and toxic metal overload. However, the particular mechanisms of the role of trace element dysbalance in chronic rhinosinusitis are unclear. We hypothesize that exposure to toxic trace elements (arsenic, nickel, cadmium) damages ciliary mucosal epithelium thus affecting mucociliary transport. In turn, altered mucociliary transport results in reduced removal of the inhaled metal-containing particles from nasal mucosa leading to their absorption and further aggravation of toxicity. Essential trace elements (zinc, selenium) play a significant role in regulation of mucociliary transport and immunity, thus their deficiency (either dietary or due to antagonism with toxic metals) may be associated with impaired functions and increased toxic metal toxicity. Therefore, a vicious circle involving metal accumulation and toxicity, essential element deficiency, impairment of mucociliary transport and metal particle removal, resulting in further accumulation of metals and aggravation of toxic effects is formed. The present hypothesis is supported by the findings on the impact of trace elements especially zinc and arsenic on mucociliary clearance, the role of mucociliary transport in heavy metal particles elimination from the airways, trace element dysbalance in chronic rhinosinusitis, as well as toxic and essential metal antagonism. The data from hypothesis testing and its verification may be used for development of therapeutic approach for management of chronic rhinosinusitis. Particularly, the use of essential elements (zinc, selenium) may reduce toxic metal toxicity thus destroying the vicious circle of heavy metal exposure, toxicity, alteration of mucociliary clearance, and aggravation of chronic rhinosinusitis. Essential element supplementation may be considered as a tool for management of chronic refractory rhinosinusitis. In addition, analysis of essential and toxic trace element status may provide an additional diagnostic approach to risk assessment of chronic rhinosinusitis in highly polluted environments.

A Randomized Clinical Trial of Elemental Zinc Add-on Therapy on Clinical Outcomes of Patients with Chronic Rhinosinusitis with Nasal Polyposis (CRSwNP)

Recent studies suggest a relationship between zinc deficiency and inflammation. In the present study, we studied the effect of oral zinc supplementation on clinical improvement of chronic rhinosinusitis with nasal polyposis. In this single-blind randomized controlled trial, 44 patients with chronic rhinosinusitis with polyposis referring to ENT clinic of the Loghman Hakim hospital during 2013-2014 were randomly allocated in two groups. The treatment group (n = 28) was treated with a four-drug fixed-dose regimen (FD_FDR) consisting of oral dexamethasone (0.02 mg/kg), fluticasone nasal spray, fexophenadine 60 mg daily, montelukast 10 mg daily plus 220mg zinc sulfate capsules containing 55 mg elemental zinc, b.d., and the control group (n = 16) received the FD_FDR without supplemental zinc, for six weeks. After sixth week, two groups were compared regarding clinical outcomes based on theSNOT20 (Sinonasal outcome test) questionnaire, the general health questionnaire (SF12), the Lund-Mackay, and the Lund-Kennedy scoring systems. In the treatment group, serum zinc levels were significantly increased compared to those at the baseline (1.33 fold-increase; p = 0.0002). Within groups analysis revealed a significant reduction (p < 0.01) in LM and LK in both treatment (55% LM; 50% LK) and control groups (45% LM; 53% LK). Incontrast, between groups analysis revealed no significant differences in the LM and LK. The treatment group showed a mild superiority in general health improvement compared to that of the control group. Add-on therapy with supplemental zinc sulfate was not associated with significant improvement in patients with chronic rhinosinusitis with nasal polyposis (CRSwNP). The advantage of zinc supplementation on the general health improvement of the patients with CRSwNP requires further assessments.

Oxidative Status in Patients with Benign Paroxysmal Positional Vertigo

OBJECTIVE

Benign paroxysmal positional vertigo (BPPV) is the most frequent peripheral vestibular disorder and is particularly seen among older patients suffering from vertigo. The brief vertigo attacks in and imbalance symptoms of BPPV are caused by freely floating otoconia within the semicircular canals. The aim of this prospective study was to evaluate the role of oxidative stress, using native thiol/disulfide (SH/SS) homeostasis as a novel indicator, in the etiology of BPPV.

MATERIALS AND METHODS

The 62 participants in the study included 31 patients with BPPV and, as the control group, 31 healthy individuals without any cochleovestibular disorders.

RESULTS

Patients with BPPV initially had significantly lower native SH levels and significantly lower SH/total thiol (TT) ratios, as well as significantly higher SS/SH and SS/TT ratios, than the healthy controls. After successful treatment of their vertigo, which was confirmed based on the results obtained from the second blood sample, patients with BPPV still had lower SH levels and SH/TT ratios and significantly higher SS/SH and SS/TT ratios than the healthy controls.

CONCLUSION

Our results suggest a role of oxidative stress in the development of BPPV, through both calcium metabolism and the direct toxic effects of free oxygen radicals, including the triggering of apoptosis.

Trace element levels in patients with familial mediterranean Fever

OBJECTIVE

Although the genetic etiology of familial Mediterranean fever (FMF) is known, limited information is available regarding the regulation of inflammation during attack-free periods. The aim of this study was to determine the alterations in serum copper (Cu), zinc (Zn) and selenium (Se) levels that may be associated with inflammation during attack-free periods in FMF patients.

MATERIALS AND METHODS

This study included 33 patients with FMF and 30 healthy volunteers. Erythrocyte sedimentation rate (ESR), the serum C-reactive protein (CRP) level and serum levels of Cu, Zn and Se in FMF patients and healthy volunteers were assessed by the atomic absorption spectrophotometry method.

RESULTS

ESR and serum CRP levels and serum Cu and Zn levels were similar between patients with FMF during an attack-free period and healthy controls (p>0.05). Serum Se levels in the patient group were significantly higher than in the control group (p<0.05).

CONCLUSION

Our study shows that levels of trace elements in serum are variable in patients with FMF during attack-free periods. Serum Se concentrations may at least in part contribute to the subclinical inflammation in FMF patients during attack-free periods. However, further studies are necessary to confirm this result.

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.

Common respiratory diseases

The self-medication phenomenon in upper respiratory tract infections, rhinosinusitis, asthma, and chronic obstructive pulmonary disease are significant and will continue to increase. Current level of evidence is poor because of the small number of good quality studies, small sample size, short duration, and variation in the composition of the herbal interventions or therapies. The current review points to several potential therapies that could be effective either alone, or as adjuncts to conventional therapies.

The effects of methylprednisolone and cefazolin sodium on antioxidant status in experimentally induced maxillary sinusitis

CONCLUSION

Sinusitis is accompanied by deteriorated antioxidant status, which can be alleviated with administration of cefazolin sodium or methylprednisolone. Steroids improve sinusitis when combined with antibiotics.

OBJECTIVE

To evaluate the antioxidant status in response to treatment of maxillary sinusitis with methylprednisolone and cefazolin sodium.

MATERIALS AND METHODS

Twenty-eight rabbits were inoculated with Staphylococcus aureus and then treated with saline, methylprednisolone, cefazolin sodium, and methylprednisolone plus cefazolin sodium, twice daily for 7 days. After the animals were sacrificed, mucosa samples were obtained to determine catalase (CAT), superoxide dismutase (SOD), and glutathione reductase (GPx) activities and levels of nitric oxide (NO) and malondialdehyde (MDA).

RESULTS

Catalase activity among untreated rabbits and those treated with either methylprednisolone or cefazolin sodium was not different. Activities of SOD and GPx were lower for rabbits treated with cefazolin sodium than for those treated with methylprednisolone and for untreated rabbits (p<0.0001). Rabbits treated with cefazolin sodium had lower NO and MDA levels than those treated with methylprednisolone and untreated rabbits (p<0.0001). Combined administration of cefazolin sodium with methylprednisolone increased CAT, SOD, and GPx activities further and decreased NO and MDA levels further in comparison with their administration alone (p<0.0001).

Effect of L-ascorbate on chloride transport in freshly excised sinonasal epithelia

BACKGROUND

Chronic rhinosinusitis (CRS) occurs at high frequency in patients with cystic fibrosis, suggesting that the cystic fibrosis transmembrane conductance regulator (CFTR) chloride (Cl) ion channel might be involved in the development of chronic sinusitis in the general population. CFTR Cl ion transport controls the hydration of mucosal surfaces and promotes effective mucociliary clearance. Altered ion transport and, hence, disrupted mucociliary function, could play a role in the pathogenesis of sinus disease. L-ascorbate is a metabolically active component of the nasal and tracheobronchial airway lining fluids and appears to serve as an important biological effector of CFTR-mediated chloride secretion. The purpose of this study was to determine the effects of L-ascorbate on Cl ion transport in freshly excised sinonasal epithelia from normal controls and patients with CRS.

METHODS

Four different types of sinonasal tissue (normal sinus mucosa, sinus mucosa from CRS, normal nasal mucosa, nasal mucosa from CRS) were obtained during endoscopic sinus surgery and mounted on sliders with open areas of 0.03-0.71 cm2 between Ussing hemichambers. Short-circuit current (Isc) was continuously recorded, and a serosa-to-mucosa-directed Cl gradient was applied to increase the electrochemical driving force.

RESULTS

L-ascorbate (500 microM) stimulated Cl currents (DeltaI(Cl), microA/cm2) across sinonasal epithelia from normal and CRS patients. The Cl secretory response to L-ascorbate was effectively blocked by the Cl ion transport inhibitors glibenclamide and bumetanide. A maximal dose of L-ascorbate (at 1 mM) stimulated 53-70% of Cl currents elicited by the cAMP agonist forskolin. CRS sinonasal tissue was characterized by impaired Cl secretory responses to L-ascorbate that were reduced by 33% in sinus epithelial tissue and by 70% in nasal epithelial tissue when compared with normal subjects. In nasal epithelial tissue from normal subjects, Cl secretion was approximately twofold increased when compared with sinus epithelial tissue. In contrast, nasal versus sinus epithelial tissue from CRS patients showed no differences.

CONCLUSION

Topical administration of L-ascorbate to freshly excised sinus and nasal mucosa enhances chloride secretion. Given that decreased CFTR-mediated Cl secretion may contribute to the development of CRS, L-ascorbate may offer potential as a therapeutic agent for the improvement of mucociliary clearance.

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.