Composition containing monoacetyldiacylglycerol compound as active ingredient for preventing or treating asthma

Abstract

The present invention relates to a pharmaceutical composition containing a monoacetyldiacyiglycerol compound as an active ingredient for preventing or treating asthma, and a functional health food composition for preventing or treating asthma. The monoacetyldiacylglycerol compound of the present invention inhibits the expression of IL-4 in EL-4 cells, which are mouse T cell lymphoma cells, reduces hypersensitivity of airway in an asthma-induced animal model, and inhibits the infiltration of inflammatory cells into the bronchial tube. In addition, the compounds of the present invention inhibit the generation of IgE in the serum and bronchoalveolar lavage fluid, have an excellent effect of inhibiting the expression of Th2 cytokines (IL-4, IL-5, and IL-13) in the lung, thereby overcome side effects of the currently used therapeutic agents for asthma, have no toxicity, and exhibit a superior therapeutic effect, and thus can be useful as a composition for preventing, treating, and alleviating asthma.

Claims

1. A method for treating asthma, comprising: administering to a subject suffering from or susceptible to asthma an effective amount of a compound of the following Formula (I): ##STR00005## wherein R1 and R2 are independently selected from the group consisting of palmitoyl, oleoyl, linoleoyl, linolenoyl, stearoyl, myristoyl, and arachidonoy.

2. The method of claim 1, wherein an effective amount of a compound of the following Formula 2 is administered to the subject: ##STR00006##

3. The method of claim 1 wherein the subject is suffering from bronchial asthma, allergic asthma, atopic asthma, non-atopic asthma, exercise-induced asthma, cardiac asthma or alveolar asthma.

4. The method of claim 1 wherein the compound of Formula 1 reduces the secretion of cytokine selected from the group consisting of IL-4, IL-5 and IL-13.

5. The method of claim 1 wherein the compound of Formula 1 reduces the secretion of IgE.

6. The method of claim 1 wherein the compound of Formula 1 reduces the inflammatory cells around the bronchi or vessels or reduces the mucus secretion of goblet cells of the bronchial epithelium.

7. The method of claim 1 wherein R1 and R2 (R1/R2) is selected from the group consisting of oleoyl/palmitoyl, palmitoyl/oleoyl, palmitoyl/linoleoyl, palmitoyl/linolenoyl, palmitoyl/arachidonoyl, palmitoyl/stearoyl, palmitoyl/palmitoyl, oleoyl/stearoyl, linoleoyl/palmitoyl, linoleoyl/stearoyl, stearoyl/linoleoyl, stearoyl/oleoyl, myristoyl/linoleoyl, myristoyl/oleoyl.

8. The method of claim 2 wherein the subject is suffering from bronchial asthma.

9. The method of claim 2 wherein the subject is suffering from allergic asthma.

10. The method of claim 2 wherein the subject is suffering from atopic asthma.

11. The method of claim 2 wherein the subject is suffering from non-atopic asthma.

12. The method of claim 2 wherein the subject is suffering from exercise-induced asthma.

13. The method of claim 2 wherein the subject is suffering from cardiac asthma.

14. The method of claim 2 wherein the subject is suffering from alveolar asthma.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 schematically shows experimental procedures performed in the present invention.

(2) FIG. 2 is a graph showing the effect of EC-18 against airway hyperresponsiveness. In FIG. 2, NC represents a normal control group; OVA represents an asthma-induced group; Mon represents a drug control group; and EC18-30 and EC18-60 represent sample-administered groups (administered with 30 mg/kg and 60 mg/kg of EC-18, respectively).

(3) FIG. 3 is a graph showing the effect of EC-18 on the number of inflammatory cells in bronchoalveolar lavage fluids.

(4) FIG. 4 is a set of graphs showing the effect of EC-18 on the secretion of cytokines in bronchoalveolar lavage fluids.

(5) FIG. 5 is a set of graphs showing the effects of EC-18 on the secretion of serum total IgE and ovalbumin-specific IgE.

(6) FIG. 6 is a set of images showing the effect of EC-18 against inflammatory responses in lung tissue.

(7) FIG. 7 is a set of images showing the effect of EC-18 against mucus secretion in lung tissue.

DETAILED DESCRIPTION OF THE INVENTION

(8) A more detailed description of the invention will be made by reference to the attached drawings. Hereinafter, the present invention will be described in further detail with reference to examples. It is to be understood, however, that these examples are for illustrative purposes and are not intended to limit the scope of the present invention.

Example 1: Evaluation of Cytotoxicity of Monoacetyldiacylglvcerol Compounds in EL-4 Cells

(9) EL-4 cells that are mouse T lymphoma cells were suspended in 10% fetal bovine serum-containing RPMI medium (Gibco) at a concentration of 5×10.sup.4 cells/ml, and 100 μl of the cell suspension was seeded into each well of a 96-well plate and cultured for 12 hours. Next, the cell culture was treated with monoacetyldiacylglycerol (MADG) compounds at the concentrations shown in Table 1 below, and was then additionally cultured for 24 hours. Next, according to the instruction provided in a CCK-8 kit (Dojindo) capable of counting cells, 10 μl of CCK-8 solution was added to the kit and allowed to react for 30 minutes to 4 hours, and then the absorbance (OD) at 570 nm was measured. Cell viability was calculated using the following equation 1, and the results of the calculation are shown in Table 1 below. In equation 1, the negative control group indicates a cell culture treated with 0.2% DMSO. In Table 1 below, the following abbreviations were used: PLAG: 1-palmitoyl-2-linoleoyl-3-acetylglycerol; POAG: 1-palmitoyl-2-oleoyl-3-acetylglycerol; PSAG: 1-palmitoyl-2-stearoyl-3-acetylglycerol; PPAG: 1-palmitoyl-2-palmitoyl-3-acetylglycerol, OPAG: 1-oleoyl-2-palmitoyl-3-acetylglycerol; OSAG: 1-oleoyl-2-stearoyl-3-acetylglycerol; LPAG: 1-linoeoyl-2-palmitoyl-3-acetylglycerol; and LSAG: 1-linoeoyl-2-stearoyl-3-acetylglycerol.
Cell viability (%)=[(OD 570 nm value of MADC-treated group)/(OD 570 nm value of negative control group)]×100  Equation 1

(10) TABLE-US-00001 TABLE 1 EL-4 cell EL-4 cell Concentration viability (%, Concentration viability (%, Sample (μg/ml) mean ± SD) Sample (μg/ml) mean ± SD) Negative 0 100.00 ± 0.58  Negative 0 100.00 ± 2.20 control control group group PLAG 5 101.94 ± 1.47  PPAG 5 106.28 ± 1.39 (EC-18) Ec-18 10 97.54 ± 8.05 10 105.84 ± 1.38 20 91.82 ± 3.48 20  96.59 ± 0.69 50 92.67 ± 3.43 OPAG 5  98.04 ± 0.94 100 95.29 ± 2.89 10  98.91 ± 1.68 200 99.74 ± 6.14 20  99.56 ± 2.86 POAG 5 106.94 ± 2.69  OSAG 5 102.62 ± 2.18 10 106:39 ±1.19  10 100.98 ± 2.37 20 98.90 ± 1.16 20 100.22 ± 0.68 PSAG 5 98.46 ± 0.33 LPAG 5  99.67 ± 1.15 10 100.66 ± 1.25  10  98.91 ± 0.50 20 103.30 ± 2.15  20  99.13 ± 1.18 LSAG 5 103.82 ± 1.80 10 101.85 ± 1.00 20  98.15 ± 1.82

(11) As shown in Table 1 above, the cell viabilities of EL-4 cells at varying concentrations of the monoacetyldiacylglycerol (MADG) compounds were analyzed, and as a result, it was shown that EC-18 showed no cytotoxicity at a concentration of 200 μg/mL or less, and the other compounds showed no cytotoxicity at a concentration of 20 μg/mL or less.

Example 2: Inhibition of EL-4 mRNA Expression by Monoacetyldiacylglycerol Compounds

(12) Based on the results of Example 1, each of the monoacetyldiacylglycerol compounds was added to EL-4 cells at a concentration of 20 μg/mL, and the effect thereof on the inhibition of PMA-induced expression of IL-4 mRNA in the EL-4 cells was measured. Specifically, the expression level of IL-4 mRNA induced by PMA (1 ng/mL) was measured using real-time polymerase chain reaction (real-time PCR) and quantitative real time polymerase chain reaction (qPCR). For cell preparation, EL-4 cells were seeded into a 6-well plate at a concentration of 1×10.sup.6 cells/well and cultured for 12 hours, after which the cells were treated with each of the monoacetyldiacylglycerol compounds at a concentration of 20 μg/mL for 1 hour and treated with PMA at a concentration of 1 ng/ml, followed by culture for 12 hours. Total RNA was extracted from the cells using Trizol B (Invitrogen, USA) and quantified, and then cDNA was synthesized from the total RNA using an Omniscript RT kit (Qiagen, GmbH, Hilden, Germany). The synthesized cDNA as a template was mixed with each of the IL-4 and GAPDH primers shown in Table 2 below and was subjected to PCR using a PCR mix (PCR Master Mix, Bioneer, Korea) under the following conditions: denaturation at 94° C. for 5 minutes; and then 30 cycles, each consisting of 30 sec at 95° C., 45 sec at 60° C., and 45 sec at 72° C.; followed by enzyme inactivation at 72° C. for 10 minutes. The results of measuring the percent inhibition of expression of IL-4 mRNA in EL-4 cells as described above are shown in Table 3 below. The designation of each of the samples shown in Table 3 below is as described with respect to Table 1 above.

(13) TABLE-US-00002 TABLE 2 Genes Primers IF-4 Sense 5′- GAA TGT ACC AGG AGC CAT ATC -3′ Anti- 5′- CTC AGT ACT ACG AGT AAT CCA -3′ sense GAPDH Sense 5′- AAC TTT GGC ATT GTG GAA GG -3′ Anti- 5′- ACA CAT TGG GGG TAG GAA CA -3′ sense

(14) TABLE-US-00003 TABLE 3 Expression level of IL-4 Concentration PMA mRNA (percentage relative Sample (μg/mL) (1 ng/mL) to PMA-treated group Inhibition (%) Negative control 0 − 72.13 ± 7.13  — group PMA-treated 0 + 100.01 ± 5.91  — group PLAG 20 + 78.17 ± 6.26  21.83 POAG 20 + 75.47 ± 13.15 24.53 PSAG 20 + 70.49 ± 17.78 29.51 PPAG 20 + 48.62 ± 19.38 51.38 OPAG 20 + 58.58 ± 21.74 41.42 OSAG 20 + 55.84 ± 25.77 44.16 LPAG 20 + 61.11 ± 27.49 38.89 LSAG 20 + 41.62 ± 17.61 58.38

(15) As shown in Table 3 above, the expression level of IL-4 in the PMA-treated group increased, and the monoacetyldiacylglycerol compounds inhibited the expression IL-4 by 20-50% compared to that in the PMA-treated group (100%).

Example 3: Ovalbumin-Induced Asthma Models and Sample Administration

(16) 6-week-old female SPF (specific pathogen-free) Balb/c mice (average weight: 20 g) were purchased from Samtako (Korea). The animals were sufficiently fed with solid feed (antibiotic-free, Samyang Feed Co.) and water until the start point of the experiment, and acclimated at a temperature of 22±2° C., a humidity of 55±15%, and a 12-hr light/12-hr dark cycle for 1 week, and then used in experiments. After 1 week of the acclimation period as described above, the mice were sensitized by intraperitoneal administration of a suspension of 2 mg of aluminum oxide (A8222, Sigma-Aldrich, MO, USA) and 20 μg of ovalbumin (A5503, Sigma-Aldrich) in 200 μl of phosphate buffered saline at two-week intervals. During a period from day 21 to day 23 after the first intraperitoneal administration of ovalbumin, 1% ovalbumin was inhaled into the mice for 30 minutes using an ultrasonic nebulizer (NE-U12, Omron Corp., Japan). At 24 hours after the last ovalbumin challenge, the airway hyperresponsiveness of the mice was measured, and after 48 hours, the mice were anesthetized by intraperitoneal administration of Pentobarbital (50 mg/kg, Entobal, Hanil, Korea). Then, blood was collected through the saphenous vein, and the mice were subjected to tracheostomy. Next, each of the mice was subjected to bronchoalveolar lavage with a total of 1.4 ml of PBS to collect an analytical sample. The mice were divided into: a normal control group (NC; a group not administered and inhaled with ovalbumin); an asthma-induced group (OVA; a group administered and inhaled with ovalbumin); a drug control group (Mon; a group administered with 30 mg/kg of montelukast+administered and inhaled with ovalbumin); and sample-administered groups (EC18-30 and EC18-60; groups administered with 30 mg/kg and 60 mg/kg of EC-18, respectively, + administered and inhaled with ovalbumin). The drug and the sample were administered orally during a period from day 18 to day 23 after the first ovalbumin challenge (FIG. 1). Seven mice were used per group.

Example 4: Measurement of Airway Hvperresponsiveness

(17) To measure airway hyperresponsiveness that is one of the major features of asthma, one chamber plethysmography (All Medicus, Korea) was used. The degree of airway resistance was evaluated by measuring enhanced pause (Pehn). For measurement of Pehn, the basis value was measured in a normal breathing state, and then PBS was inhaled for 3 minutes using an ultrasonic nebulizer, after which the Pehn value was measured for 3 minutes. Next, methacholine (A2251, Sigma-Aldrich) was inhaled while the concentration thereof was gradually increased from 12 to 25 and 50 mg/ml and then the Pehn value was measured. The results of the measurement are shown in Table 4 below.

(18) TABLE-US-00004 TABLE 4 Methacholine concentration (mg/mL) Group 0 12.5 25 50 NC 0.308 ± 0.04 0.432 ± 0.03 0.639 ± 0.14 1.302 ± 0.10 OVA 0.965 ± 0.07.sup.# 1.629 ± 0.14.sup.#  4.37 ± 0.28.sup.# 7.318 ± 1.51.sup.# Mon 0.590 ± 0.07* 1.261 ± 0.29* 3.046 ± 0.61* 4.182 ± 0.99* EC18-30 0.465 ± 0.08* 1.179 ± 0.49* 2.914 ± 0.67* 4.098 ± 0.78* EC18-60 0.436 ± 0.08* 0.778 ± 0.15* 2.436 ± 0.68* 3.887 ± 0.59*

(19) As shown in FIG. 4 above, the Pehn value in the asthma-induced group greatly increased compared to that in the normal control group, and the Pehn value in the montelukast-administered group (drug control group) significantly decreased compared to that in the asthma-induced group. The airway hyperresponsiveness in all the groups administered with 30 mg/kg and 60 mg/kg of EC-18 significantly decreased compared to that in the asthma-induced group, and was similar to that in the montelukast-administered group (FIG. 2).

Example 5: Isolation of Bronchoalveolar Lavage Fluid (BALF) and Counting of Total Cells

(20) An increase in the number of eosinophils is one of the major features of asthma. Thus, in order to measure the number of eosinophils, the following experiment was performed. The bronchoalveolar lavage fluid from each mouse was stained with trypan blue immediately after collection, and the number of total cells (excluding dead cells) was calculated using a hemocytometer. Next, the cells were attached to a slide using Cytospin (Hanil, Korea), and then subjected to Diff-Quik staining (Sysmex, Switzerland), and eosinophils and other inflammatory cells were observed with a microscope. Next, the number of inflammatory cells in each sample was counted, and the results of the cell counting are shown in Table 5 below.

(21) TABLE-US-00005 TABLE 5 Inflammatory cell number (10.sup.5 per mouse) Group Eosinophils Macrophages Lymphocytes Neutrophils Total cells NC  0 ± 0.0  7 ± 1.7  2 ± 0.5  0 ± 0.0  9 ± 2.0 OVA 137 ± 11.4.sup.# 136 ± 10.9.sup.# 25 ± 5.0.sup.# 19 ± 7.1.sup.# 317 ± 7.0.sup.# Mon  54 ± 17.8*  99 ± 21.4* 11 ± 10.6 14 ± 5.2 179 ± 44.0* EC18-30  93 ± 16.4*  82 ± 25.5* 16 ± 8.7 15 ± 8.4 221 ± 33.5* EC18-60 112 ± 18.7* 113 ± 27.4 13 ± 8.7 12 ± 6.7 253 ± 12.8*

(22) As shown in Table 5 above, the number of total inflammatory cells in the asthma-induced group greatly increased compared to that in the normal control group, and particularly, an increase in the number of eosinophils was characteristically observed. However, the groups administered with EC-18 showed a significant decrease in the number of total inflammatory cells together with a decrease in the number of eosinophils, compared to the asthma-induced group (FIG. 3).

Example 6: Analysis of Cytokines in Bronchoalveolar Lavage Fluid (BALF)

(23) The production of interleukins (IL-4, IL-5 and IL-13) in the bronchoalveolar lavage fluid isolated from each mouse was measured using a commercially available enzyme-linked immunosorbent assay (ELISA) kit (R&D System, USA). The analysis of each cytokine was performed according to the manufacturer's instruction, and the absorbance at 450 nm was measured using an ELISA reader (Molecular Devices, USA). The results of the analysis are shown in Table 6 below.

(24) TABLE-US-00006 TABLE 6 Th2 cytokines (pg/mL) Group IL-4 IL-5 IL-13 NC 17.19 ± 2.29 15.64 ± 1.12 18.53 ± 2.45.sup.   OVA 27.57 ± 4.93.sup.#  38.97 ± 3.56.sup.# 142.48 ± 19.75.sup.#  Mon 18.69 ± 3.00* 22.74 ± 3.59* 81.42 ± 25.59* EC18-30 17.89 ± 3.46* 24.12 ± 3.07* 97.27 ± 12.80* EC18-60 17.09 ± 3.08* 25.02 ± 2.91* 81.10 ± 20.46*

(25) A shown in Table 6 above, the secretion of the Th2-type cytokine IL-4 in the asthma-induced group greatly increased compared to that in the normal control group, whereas the secretion of IL-4 in the montelukast-administered group significantly decreased compared to that in the asthma-induced group. Furthermore, the secretion of IL-4 in the EC-18-administered groups significantly decreased compared to that in the asthma-induced group. In addition, the secretion of IL-5 and IL-13 in the EC-18-administered groups significantly decreased compared to that in the asthma-induced group (FIG. 4).

Example 7: Measurement of Serum IqE and Ovalbumin-Specific IqE

(26) The blood collected through the saphenous vein was incubated at room temperature for 30 minutes, and then centrifuged (3000 rpm, 15 min) to obtain serum. For measurement of serum IgE and ovalbumin-specific IgE, ELISA was used. IgE was measured using commercially available IgE (Biolegend Ins., USA). For measurement of ovalbumin-specific IgE, in a 96-well flat bottom ELISA plate, ovalbumin was dissolved in 0.1 M NaHCO.sub.3 buffer (pH 8.3) at a concentration of 20 μg/mL and incubated at 4° C. for 16 hours. Next, PBS containing 1% bovine serum albumin (BSA) was added to suppress nonspecific reactions. The serum sample was diluted at 1:400, allowed to react at room temperature for 2 hours, and then washed with PBS containing 0.05% Tween 20. Horseradish peroxidase (HRP)-conjugated goat anti-rat IgG polyclonal A was diluted 4000-fold and allowed to react at room temperature for 1 hour, and then color development was performed using 3,3′5,5′-tetramethylbenzidine substrate. Next, the absorbance at 450 nm was measured, and the results of the measurement are shown in Table 7 below.

(27) TABLE-US-00007 TABLE 7 Group IgE (μg/mL) OVA specific IgE (μg/mL) NC 0.30 ± 0.13 — OVA 3.03 ± 0.34.sup.# 438.84 ± 90.75.sup.# Mon 2.03 ± 0.49* 198.15 ± 42.65* EC18-30 2.35 ± 0.38* 295.36 ± 77.93* EC18-60 2.27 ± 0.46* 287.79 ± 69.53*

(28) As shown in Table 7 above, serum IgE in the asthma-induced group significantly increased compared to that in the normal control group, whereas serum IgE in the drug control group (montelukast-administered group) significantly decreased compared to that in the asthma-induced group. Furthermore, serum IgE in all the groups administered with EC-18 significantly decreased compared to that in the asthma-induced group, and was similar to that in the montelukast-administered group. In addition, ovalbumin-specitic IgE in the asthma-induced group greatly increased compared to that in the normal control group, whereas ovalbumin-specific IgE in all the groups administered with EC-18 significantly decreased compared to that in the asthma-induced group (FIG. 5).

Example 8: Histopathological Examination

(29) The lung was isolated from each mouse, and then immediately, fixed in 10% formaldehyde solution, cut finely, washed with running water for 8 hours, embedded in epoxy, and then sectioned with a microtome. Next, Hematoxylin & Eosin staining was performed in order to observe inflammation in the lung tissue. In addition, because mucus secretion in the bronchi significantly increases when asthma was induced, periodic acid Schiff (PAS, IMEB Inc., USA) staining was performed in order to observe the mucus secretion. Pathological changes in the lung tissue were observed using an optical microscope.

(30) (1) When inflammatory reactions in the lung tissue were examined, the extensive infiltration of inflammatory cells around the bronchi and blood vessels of the asthma-induced group was observed. However, in the montelukast-administered group, a decrease in the infiltration of Inflammatory cells was observed, and in all the groups administered with EC-18, a decrease in the infiltration of inflammatory cells around the bronchi and blood vessels was observed. This decrease was similar to that in the montelukast-administered group (FIG. 6).

(31) (2) When mucus secretion in the bronchi was examined, an increase in mucus secretion from goblet cells of the bronchial epithelium in the asthma-induced group was observed. However, it was shown that mucus secretion in the montelukast-administered group decreased, and mucus secretion from goblet cells of the bronchial epithelium in all the groups administered with EC-18 significantly decreased (FIG. 7).

(32) While the present invention has been described with reference to the particular illustrative embodiments, it will be understood by those skilled in the art to which the present invention pertains that the present invention may be embodied in other specific forms without departing from the technical spirit or essential characteristics of the present invention. Therefore, the embodiments described above are considered to be illustrative in all respects and not restrictive. Furthermore, the scope of the present invention should be defined by the appended claims rather than the detailed description, and it should be understood that all modifications or variations derived from the meanings and scope of the present Invention and equivalents thereof are included in the scope of the present invention.