Changes in IgE, HLA-DR and Glutathione Antioxidant Pathway Components in Blood from Asthma Patients Treated with Ozone Therapy

Author Frank Hernández
Author Idania Alvarez
Author Ivonne Corcho José L
Author Calunga, José Turrent
Author Silvia Menéndez
Author Adonis Montenegro
Author Maritza González
Publication Department of Biomedicine, Ozone Research Center, National Center for Scientific Research, A.Postal 6412, Ciudad de La Habana, Cuba.
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Changes in IgE, HLA-DR and Glutathione Antioxidant Pathway Components in Blood from Asthma Patients Treated with Ozone Therapy

Abstract

We have studied the relationship and behavior of serum imunoglobulin E (IgE) level, peripheral mononuclear cell human leukocyte antigen DR (HLA-DR) expression and erythrocyte glutathione antioxidant pathway in a group of patients suffering reactive asthma. These patients were treated by three cycles with three ozone therapy different protocols. Ozone major autohemotherapy [MAHT] (each cycle of 15 sessions at doses of 4 and 8 mg) and ozone rectal insufflations [RI] (each cycle of 20 sessions at dose of 10 mg). IgE and HLA-DR decreased with the three types of treatments, while increments in Reduced glutathione, Glutathione peroxidase, Glutation reductase and Glutathione S-trasferase were achieved with all treatments. Lung function and symptom tests were markedly improved. However, in all parameters the best response was obtained in the order MAHT at 8mg better than MHAT at 4mg better than RI at 10mg. Before ozone treatment glutathione antioxidant parameters were under the reference normal values suggesting the occurrence of oxidative stress associated to the atopic asthma. This study demonstrates the effectiveness of ozone therapy in reducing IgE and inflammatory mediators along with the induction of antioxidant elements. The study raises the role of systemic ozone therapy in atopic asthma by means of the immunomodulatory and oxidative stress regulation properties of this therapy.

Introduction

Allergic asthma is characterized by airway hyperresponsiveness and airway inflammation. Population studies have shown that the majority of adults and children with well-documented asthma are atopic, and the prevalence of asthma is greater in subjects with high serum immunoglobulin E (IgE) levels in a close relation with inflammatory cells (1-3). Examination of bronchoalveolar lavage (BAL) fluid cells and supernatants from allergic asthmatics has revealed the existence of Th2-like cytokine patterns (4,5) together with the IgE elevation (6). Increased IgE level in peripheral blood and bronchoalveolar tissue has been directly associated with atopic asthma pathology (7,8). Therefore, some therapeutic strategies today in atopic asthma are addressed to reduce IgE (9-11).

On the other hand, bronchial epithelial cells, lymphocytes and dendritic cells also play an active role in asthma. After allergen activation they release increased amounts of inflammatory mediators (12-14) and express higher levels of human leukocyte antigen DR (HLA-DR) molecule (15,17), which have been implicated in the cellular network underlying inflammation in asthma.

Systemic ozone therapy has been proved to be effective to modulate immune system by inducing the production of cytokines from blood mononuclear cells (18,19), and to regulate the oxidative stress by inducing an increase of cellular antioxidant system (20-22).

Taking into account that Th2 cytokines are pivotal in regulating the allergic phenotype, the Ig E response or the inflammatory cell-mediated function (23), we explore the hypothesis that systemic ozone therapy has a beneficial role in asthma by reducing IgE level and inflammatory mediators along with a positive influence on the antioxidant defense system.

Materials and Methods

Patients and treatments

113 asthmatic patients (aged from 15 to 50 years) including both sexes were treated by ozone therapy. Two groups of them were treated with 3 cycles of ozone major autohemotherapy (MAHT).  Each cycle comprised of 15 sessions (5 a week) of MAHT using an ozone dose of 4 mg (20 mg/mL per mL of blood and 200 mL of volume) or 8 mg (40 mg/mL per mL of blood and 200 mL of volume). A third group was treated with 3 cycles of ozone therapy by rectal insufflation (RI). Each cycle comprised of 20 sessions of RI using an ozone dose of 10 mg (50 mg/mL and 200 mL of gas volume). Time between cycles was 5 or 6 months in all groups. No other medication was given during the study.

Determinations

Blood samples were drawn from patients before and at the end of each cycle. Red blood cells, serum and peripheral blood mononuclear cells (PBMC) were obtained by gently centrifugation and Ficoll-Hypaque-dextran gradient. Total serum IgE quantification was done using an immunoenzymatic ELISA kit, commercially available. For HLA-DR measurement a flow cytometry study on lymphocyte subpopulation was done using the ior dr1 (IgG2a) anti HLA class II fluorescent (FITC) monoclonal antibody. Reduced glutathione (GSH) and Glutathione reductase (GR) were measured in erythrocytes using the methods of Beutler (24). Erythrocyte Glutathione peroxidase (GPx) and Glutation S-transferase (GST) activities were measured by the modification of Faraj et al. (25) to the method of Thomson (26) and by the method proposed by Habig and Jakoby (27), respectively.

Symptoms scores were recorded and respiratory function tests (forced expiratory volume at 1 second [FEV1] and forced vital capacity [FVC]) were done using baseline spirometry tests before and at the end of each cycle.

Statistical analysis

Analysis of the results was done using the values before starting the first cycle and those at the end of the third cycle of treatment. Results are expressed as mean±SD. Comparison of matched samples was done by Wilcoxon test. A p-value equal to or less than 0.05 was considered to be statistically significant.

Results and Discussion

Patient classification

Serum Ig E and PBMC HLA-DR expression values, before ozone therapy, are exposed on table I. Average IgE level were 193 ± 73 IU/mL for MAHT 4mg, 225 ± 87 IU/mL for MAHT 8mg, and 196 ± 52 IU/mL for RI 10mg; whereas HLA-DR averages were 32 ± 12 % for MAHT 4mg, 27 ± 12 % for MAHT 8mg, and 29 ± 12 % for RI 10mg. Very high abnormal values were not present in any of the three groups indicating that all patients had not the same asthma stage, therefore, they would not equally respond to the treatment.

 

Treatment

IgE

(IU/mL)

HLA-DR

(%)

MAHT 4mg (n = 35)

193 ± 73

32 ± 12

MAHT 8mg (n = 41)

225 ± 87

27 ± 10

RI 10mg (n = 37)

196 ± 52

29 ± 12

MAHT = major autohemotherapy
RI = rectal insufflations
n = number of patients

Consequently, a distribution according to serum Ig E level and PBMC HLA-DR expression was done (Table II). Patients with very high figures in both parameters compiled for only 43 %. The rest of the patients had at least one of these parameters below the cut off levels. We have established high cut off levels of 250 IU/mL for Ig E and 35 % for HLA-DR; however, others authors assume cut off levels between 121 and 150 for IgE (28-30), and under 25 % for HLA-DR (16,31). This is the reason because many patients are in the normal subgroup in our study. We have established high cut off levels in order to be sure we are evaluating a real atopic subgroup of asthmatic patients.

Ozone therapy effects on IgE, HLA-DR and Glutathione antioxidant pathway.

Comparison of figures at the end of third cycle with those before the first shows the following aspects. Figures 1 and 2 show MAHT at a dose of 4 mg produced a slight decrease in IgE level (15 %) and HLA-DR expression (10 %), non-statistically significant. However, MAHT at a dosage of 8 mg deeply decreased Ig E level (61 %) and HLA-DR expression (57 %) in a significantly manner. RI at 10 mg also induced a significantly decrease in both parameters (30 % for IgE and 40 % for HLA-DR). Taking into account the extension of the effect in each group, the results suggest that both parameters are closely related because their responses were very similar, and that these responses are ozone concentration and route dependent.

Table II. Subgroup classification according to high serum IgE (> 250 IU/mL) and high HLA-DR (> 35 %)

Patient subgroup

MAHT

4 mg

MAHT

8mg

RI

10 mg

Total (%)

High IgE + high HLA-DR

18

15

16

49 (43)

Normal IgE or HLA-DR

17

26

21

64 (57)

Total

35

41

37

113 (100)

MAHT = major autohemotherapy
RI = rectal insufflation

changes-in-ige-hla-dr-and-glutathione-antioxidant-pathway-components-in-blood-from-asthma-patients-treated-with-ozone-therapy-fig1

*Statistically significant

Figure 1. IgE values before first and after third cycle of ozone therapy in patients with real atopic asthma.

changes-in-ige-hla-dr-and-glutathione-antioxidant-pathway-components-in-blood-from-asthma-patients-treated-with-ozone-therapy-fig2

* Statistically significant.

Figure 2. HLA-DR values before first and after third cycle of ozone therapy in patients with real atopic asthma.

It has been suggested that reactive oxygen species (ROS) play an important role in the pathogenesis of airway inflammatory diseases (32,33). In asthma patients, a correlation has been found between the degree of bronchial responsiveness to methacholine and the production of superoxide anion by peripheral polymorphonuclear leukocytes (34,35). Katsumata et al. reported that ROS could induce bronchoconstriction and airway hyperresponsiveness in anesthetized cats (36). On the other hand, Glutathione and antioxidants enzymes have been found to protect the lung against ROS toxicity (37,38). These findings demonstrate that ROS exert a direct effect in mediating bronchial responsiveness and asthma. Because ozone therapy has the property to regulate the oxidative stress caused by ROS (20-22), we tried to know if there is some relationship between asthma immunological mediators and antioxidant defense systems. One of these antioxidant defense systems is the glutathione antioxidant pathway, which includes the enzymes GPx, GST and GR, together with GSH metabolite.

The measurement of these parameters gave the values that are showed in table III. Before ozone treatment the three groups of patients had values under normal range for GSH (<2.00 mmol/g.Hb) and GPx (<11.62 IU/g.Hb), suggesting the existence of oxidative stress in these patients. This is an evidence for the relationship between high IgE level and the oxidative stress occurrence. After ozone treatment MAHT at a dose of 4 mg induced a significant increase in GPx enzyme activity (approximately 130 %), with no significantly change in the rest of parameters. MAHT at a dose of 8 mg influenced positively all the components of the glutathione antioxidant pathway; being the major increase in the GPx (approximately 190 %), followed by GST (approximately 170 %), GSH (approximately 160 %), and finally GR (approximately 140 %). RI at a dose of 10 mg produced significant enhancement in GPx (138 %) and GST (144 %) enzymes, and no significantly changes in GSH and GR parameters.

Table III. Glutathione antioxidant pathway values before and after three cycles of ozone therapy in real atopic asthma patients

 

MAHT    4 mg.

MAHT    8 mg.

RI      10 mg

before

after

Before

After

before

after

GSH

1.65±0.14

1.75±0.39

1.78±0.22

2.86±0.34*

1.80±0.10

1.93±0.11

GPx

8.90±1.11

11.26±0.8*

7.56±1.40

14.21±1.98*

8.35±0.98

11.50±1.2*

GR

3.25±0.80

3.46±0.24

4.50±0.71

6.02±0.20*

3.89±0.23

3.91±0.4

GST

6.55±0.35

6.22±0.95

5.84±1.21

9.99±0.80*

7.01±1.01

10.08±1.1*

Values for GSH are expressed in mol/g Hb, and for GPx, GR, and GST are expressed in IU/g Hb.
* statistically significant.

It is evident MAHT at ozone dose of 8 mg induced the most powerful response in stimulating the glutathione antioxidant pathway; followed by the response induced by RI at ozone dose of 10 mg. MAHT at 4 mg produced a mild response. Therefore, the effect on glutathione antioxidant pathway was also dose and route dependent. This behavior was inversely similar to that seen for IgE and HLA-DR. For that reason we assumed there was a close relationship between the asthma immunological mediators and the antioxidant system in these patients. It is important to point out that all groups of patients remarkably improved their oxidative stress condition.

Marked improvement in objective function tests was achieved after three cycles of ozone therapy (Table IV). There were increments with high significant differences in the mean from FVC and FEV1 with MAHT 8mg. But, patients with MAHT 4mg did not have significant increment of these function tests although a trend to elevate these values is observed. Patients with RI 10mg had a significant increase in FEV1 but no in FVC. Comparison between the three groups of patients shows that the highest increment for FEV1 was obtained with MAHT 8mg followed by RI 10mg and MAHT 4mg in accord with the behavior observed for the responses of IgE, HLA-DR and antioxidants biomarkers.

Table IV. Effect of ozone therapy on pulmonary function tests before and after 3 cycles of treatment.

 

Before

After

MAHT 8mg

FVC (L)

2.34 ± 0.28

2.99 ± 0.60 **

FEV1 (L)

1.46 ± 0.20

2.20 ± 0.57 ***

FEV1 (%)

46.00 ± 8.10

73.25 ± 19.70 ***

MAHT 4mg

FVC (L)

2.39 ± 0.39

2.63 ± 56

FEV1 (L)

1.56 ± 0.33

1.79 ± 0.53

FEV1 (%)

49.60 ± 14.68

57.60 ± 20.36

RI 10mg

FVC (L)

2.44 ± 0.45

2.59 ± 0.56

FEV1 (L)

1.59 ± 0.39

1.81 ± 0.52 *

FEV1 (%)

50.53 ± 13.58

59.63 ± 20.46 *

* p< 0.005; ** p< 0.002; *** p< 0.001

There was also marked improvement in clinical symptoms. Clinical amelioration achieved in episodic dyspnea, wheezing and medication was reported with the same behavior pattern observed for lung function tests (data not shown). Therefore, the present data corroborate the beneficial effects of ozone therapy in asthma patients.

In a previous paper we have demonstrated MAHT at 8 mg induces a significant reduction in serum IgE and HLA-DR expression in PBMC, together with a modulation in CD3+, CD4+ and CD8+ lymphocyte subpopulations (39). In our present study, we found similar results for IgE and HLA-DR together with remarkable induction of glutathione antioxidant system and improvement in function and symptom tests using MAHT at an ozone dose of 8 and 4 mg and RI at 10 mg. Essentially close agreement in the response pattern for all parameters suggests that ozone therapy modulated the immune system for IgE production along with the induction in antioxidant system. These events allowed the improvement in the asthma state.

The mechanism for immune system modulation is not yet totally proved. We can indirectly assume ozone therapy influenced synthesis and release of cytokines (18,19) in such a way that a change from Th2 to Th1 (IL-2, IFNg) cytokine pattern occurs, or ozone therapy acted as Th2 cytokine inhibitor. The change in cytokine pattern could be the reason for the reduction in the release and expression of asthma mediators (IgE, HLA-DR,) (40,41). Changes from Th2 to Th1 cytokine pattern have been demonstrated to counteract the airway hyperresponsiveness and bronchial inflammation (42). In the presence of IL-4 and Il-13, the B cell undergoes class switching to produce IgE (43), which can induce the release of pro-inflammatory cytokines and the expression of HLA-DR.  It is important to remark that ozone concentration is a fundamental point for cytokine release (44,45). Our results are in accordance with this concept because our better results were in the proposed ozone concentration range for cytokine release. Combination of the expressed actions may be the possible mechanism by which ozone therapy has its beneficial effect on asthmatic patients. However, an experimental evidence of cytokine type released after ozone therapy application is needed. This will be our next objective.

In summary our study corroborate the outstanding role of IgE and its direct relationship in producing oxidative stress and subsequent bronchial inflammation in allergenic asthma patients. Moreover, we have proved the hypothesis that in these patients systemic ozone therapy reduces IgE level and PBMC HLA-DR expression along with antioxidant system induction. Thus, ozone therapy can be a new therapeutically approach for atopic asthma thanks to its immunomodulation and oxidative stress regulation properties.

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