Antiviral Composition Comprising Λlnus pendula Extracts
TECHNICAL FIELD
The present invention relates to an antiviral composition comprising Alnus pendula extracts, more specifically, relates to a composition for preventing or treating diseases caused by influenza virus which infects human, pig, horse, bird, and the like.
BACKGROUND ART
Viruses cause various diseases, particularly, a typical one among pathogenic viruses that become a problem in the field of stockbreeding is avian influenza virus. Avian influenza virus belongs to the orthomixoviridae family, and cause damage to poultry such as chicken, turkey. Avian influenza virus is classified into 3 types of high- pathogenic, low-pathogenic and non-pathogenic avian influenza viruses according to the degree of pathogenicity, among which the high-pathogenic is classified into "grad A" in the World Organization for Animal Health (OIE) and "the first level domestic animal infectious disease" in Republic of Korea.
The influenza virus is classified into type A, B or C according to the antigenicity of nucleocapsid protein and matrix protein. Moreover, according to the difference of antigen structure of haemagglutinin (HA) and neuraminidase (NA), the HA is classified into 16 subtypes and NA is classified 9 subtypes, wherein HA helps host cell receptor binding, and fusion between host cell membrane and viral envelope to cause a virus infection and NA plays an important role when virus buds out through the cell membrane after proliferation. Theoretically, 144 kinds of virus subtypes could exist by the combination of two proteins. Infection generally occurrs by contact with bird secretions, furthermore, it is spread through the air, in both particle and droplet forms, human feet, vehicle delivering feedstuff, apparatus and feces on
the surface of eggs etc.
Although there are various symptoms according to the pathogenicity of infecting virus, generally, they are respiratory symptoms, diarrhea and a sharp decline in egg production ratio etc. Moreover, in some cases, cyanosis appears at the head region such as crest, edema appears on the face, or feathers are ruffled. Mortality rate also varies from 0% to 100% according to pathogenicity, but since the symptoms are similar to those of Newcastle Disease, infectious larynogotracheitis, mycoplasma infection and the like, an accurate diagnosis is required.
High-pathogenic avian influenza had occurred 23 times from 1959 to 2003 throughout the world, most of them were endemic and contained. Outbreaks of H5N1 subtype high-pathogenic avian influenza had occurred in Korea in December 2003 occurred in more than 30 countries including Europe, Africa and most countries in Southeast Asia such as Japan, China, Thailand, Vietnam and Indonesia, thus becoming pandemic. Though it is known that human cannot get infected with avian influenza, prevention of avian influenza is being of paramount importance to public health sector due to the case of human infection with H5N1 in 1997, isolation of H9N2 avian influenza viruses from humans in 1999 in Hongkong and human cases of H7 avian influenza infection in 2004 in Canada. According to a report of the World Health Organization (WHO),
(http://www.who.int/csr/disease/avian_influenza/country/cases_table_2006_06_20/en /index.html), it was confirmed that the 228 persons were infected with H5N1 subtype and 130 persons of them died during the period of 2003 to June 20, 2006 in 10 countries. In Korea, since low-pathogenic avian influenza by H9N2 subtype had occurred in 1996, it reoccurred in 1999 and now it has been occurring throughout the whole country.
If avian influenza occurs, in most countries, poultry were slaughtered, and countries which have confirmed outbreaks of avian influenza cannot export poultry products to
cause swingeing damages into poultry industry. Furthermore, when there is a risk of human infection, the damages spread to the whole industry including the tourist industry and the transport industry, thus causing astronomical loss including.
Natural substances mean, which is not added with artificial factors, and the natural substances classified as GRAS (Generally Recognized As Safe) can be used without restrictions on the quantity thereof or foods in which natural substances are to be used. In domestic industry, the natural substances are classified as natural additives, to be used as food additives, and in foreign countries, it has been used as health foods and medical supplies without extra limitation for user's purpose, because of its excellent functionality.
Meanwhile, Alnus pendula is a dicotyledon plant and a small tree classified in the division order Fagales, family Betulaceae. Its original home is Japan. Its height is 6m~8m and fluff of small branch disappears as it grows. The leaf of Alnus pendula grows alternatively and it is long oval shaped and lanceolate. Leaf margin is irregularly saw-toothed. The leaf has 16~27 pairs of veins.
The flower of Alnus pendula blooms in April prior to leaf emergence and it is monoecious. The staminate spike droops and pistillate spike extends straight. 3~6 racemes of flowers appear. The flower comprises four stamens, four perianthes and two pistils.
Recently, many researchers endeavor to develop anti-viral agents throughout the world. Lamibudine used for the treatment of HIV (Human Immunodeficiency Virus)- 1 and hepatitis B, gancyclovir used for the treatment of symptoms of herpes virus infection, ribavirin which is used mainly for the treatment of symptoms of respiratory syncytial virus infection but can be used for the treatment of symptoms of various virus infection when it is an emergency and zanamivir RELENZA™ and oseltamivir, TAMIFLU™ which are synthesized artificially as neuraminidase
inhibitors of influenza virus are all commercially available after getting approval. However, use of amantadine and its analogue, rimantadine, which are approved for treatment of influenza virus A has decreased for the appearance of resistant virus and its side effect. Recently, virus resistant to oseltamivir among H5N1 avian influenza viruses appeared, therefore, developments of various anti- virus agents are urgently required.
Therefore, the present inventors have made an extensive effort to develop a natural substance having a low toxicity to normal cells, while having an excellent effect to inhibit proliferation of influenza virus. As a result, they found that a composition comprising Alnus pendula extracts have an anti-influenza virus effect, thereby completing the present invention.
DETAILED DESCRIPTION OF THE INVENTION, AND
PREFERRED EMBODIMENTS
Main object of the present invention is to provide a food composition for preventing or treating influenza viral diseases comprising the Alnus pendula extracts.
Another object of the present invention is to provide a pharmaceutical composition for preventing or treating influenza viral diseases comprising the Alnus pendula extracts.
To achieve the above object, the present invention provides a food composition for preventing or treating influenza viral diseases belonging to the orthomixoviridae family, comprising the Alnus pendula extracts and a sitologically acceptable supplemental additive
The present invention also provides a pharmaceutical composition for preventing or
treating the influenza virus diseases belonging to the orthomixoviridae family, comprising Alnus pendula extracts as an active ingredient.
In the present invention, said influenza virus is preferably selected from the group consisting of: human influenza virus, swine influenza virus, equine influenza virus, and avian influenza virus. More preferably, said avian influenza virus is KBNP-0028 (KCTC 10866BP).
Examples
Hereinafter, the present invention will be described in more detail by examples.
However, it is obvious to a person skilled in the art that these examples are for illustrative purpose only and are not construed to limit the scope of the present invention.
Example 1: Preparation of Alnus pendula extracts
The leaves and stems (bark) of Alnus pendula were picked, dried at room temperature for 24 hrs, chopped up and crushed. The obtained powder was added with 99.9% methanol, stirred for 24hrs at room temperature to extract and vacuum-filtered to collect supernatant liquid, followed by eluting useful components from the obtained powder. The useful components are dried for 24hrs at room temperature, and dissolved in 99.9% dimethyl sulfoxide (DMSO) solution to 20 mg/ml, thus preparing Alnus pendula extracts.
Although the Alnus pendula extracts of according to the present invention could be obtained by the above described method, those distributed from The Korea Plant Extract Bank were used.
Example 2: Examination of anti-viral effect of Alnus pendula extracts
2-1: Preparation of KBNP-0028
As avian influenza virus used in the experiment, hyperproliferative KBNP-0028 (KR
2006-0026591) cloned after subculturing A/chicken/Korea/SNU0028/2000 (H9N2) virus (it is isolated in Korea in 2000) in chick embryo was used. That is, SNU0028
[A/chicken/Korea/SNU0028/2000 (H9N2); isolation and report to National
Veterinary Research and Quarantine Service, May 9, 2005] is low-pathogenic avian influenza virus of H9N2 subtype, isolated from chicken showing mortality and egg drop syndrome. The virus was isolated in a chicken farm located in North jeola Province in January 28, 2000.
The isolation method is as follows: after kidney and tracheal sample from infected chicken are dissolved, suspended in phosphate buffer, and filterated with 0.45/M diameter filter paper, each sample is inoculated into three allantoic cavities of SPF (Specific Pathogen Free) embryonated egg (Sunrise Co., NY), and cultured at 37 °C to obtain allantoic fluid. The 20 μi of allantoic fluid and 20/z# of 0.1% chicken red blood cells, extracted from a chicken obtained after hatching the SPF embryonated egg, are dropped on glass plate, and mixed to carry out plate hemagglutination test.
As a result, all of the allantoic fluids, obtained by inoculating kidney sample and tracheal sample, formed the hemagglutination. The virus was identified with RT- PCR and the analysis of base sequence using H9N2 specific primer (Kim Min Chul, Master's Thesis, 2002, Seoul National University), and stored at -70 °C . Among them, the virus isolated from tracheal sample was used in the experiment.
In order to select a vaccinia strain having high productivity of embryonated egg, the SNU0028 was diluted with phosphate buffer to the concentration of 0.05 to 0.5 HAU/ml. 200//£ of the diluted solution was inoculated into 10- 11 -day-old SPF hatchery egg (Sunrise Co., NY) via the allantoic cavity, and the egg was cultured for
three days at 37 °C . Everyday, the embryonated eggs, which died three days ago, was discarded through egg examination in the morming and afternoon. The embryonated eggs, which survived for three days, were stored for 12-24 hrs at 4°C , from which allantoic fluid was collected to measure each of volumn and hemagglutination titer thereof. Among them, allantoic fluid having the most quantity and the highest hemagglutination titer was inoculated into embryonated eggs using the same method as described above, and the eggs were subcultured 19 times to eggs whose productivity was increased due to high hemagglutination titer and high yield of allantoic fluid and thus they are named KBNP-0028. It was deposited at GenBank located Eoeundong, Youseonggu, Daejeon city, Korea on October 26, 2005 (KCTC 10866BP).
2-2: Culturing hatchery egg shell fragments
The egg shell of 10 — 11 day-old SPF hatchery egg (Sunrise Co., NY) was washed with 70% ethanol, and all of the chick embryo and body fluid were removed. The resulting egg shell is cut into about 8mm long and 8mm wide while maintaing villi, allantois adhered to the inner surface of egg shell, and put them in a 24-well culture plate piece by piece. The culture medium was prepared by (i) mixing 199 medium (GIBCO-BRL, NY, USA) with FlO medium (GIBCO-BRL, NY, USA) at a ratio of 1 :1, (ii) adding 0.075% of sodium bicarbonate and 100//g/m£ of gentamicin.
To the 10 — 11 -day-old SPF embryonated egg (Sunrise Co., NY) was infected with virus by adding 100 μl of crude allantoic fluid KBNP-0028 prepared in Example 2-1, which is 4~10-fold diluted to the surface of villi, allantois of hatchery egg shell fragments, and culturing for 30 min at 37 °C . After adding lOOOμβ of the culture medium, Alnus pendula extracts was added to 6 well plates, respectively to the concentration of 400, 300, 200 and 100μg/m£. The virus-infected fluid containing Alnus pendula extracts was cultured for 7 days at 37°C .
2-3: Test of antiviral effect
Culture broth of said virus-infected fluid containing Alnus pendula extracts at each concentration, prepared in Example 2-2 was taken to carry out plate hemagglutination test. 25 μJL of the culture broth and 25μJi of chicken red blood cells (0.1%) were dropped on glass plate in the same amount and mixed evenly. The virus proliferation was examined according to whether hemagglutination was formed within 2min after moving the glass plate right and left, and up and down. As a result, as shown in Table 1, in the case of leaves, all groups having the concentrations of 100, 200, 300 and 400 showed no antiviral effect and relative cell toxicity. In the case of stems (bark), perfect antiviral effect was shown at the concentration of 300μg/m#, and partial antiviral effect was shown at the concentration of 200μg/m# (Table 1). Therefore it was concluded that stem (bark) was the most proper material as an antiviral agent.
2-4: MTT assay
Alnus pendula extracts prepared in example 2-2 was put into 6 well plates of 400, 300, 200 and 100/zgM added with AQμJt of MTT solution (MTT 0.5% aqueous solution), respectively and cultured for 1~3 hrs at 37°C . \20μi of DMSO was added and stirred for 30 min, then the result was read at 562nm wavelength with ELISA (Table 1). As a result, as shown in Table 1, in the case of stems (bark), it was confirmed that the measured value is similar to or higher than the MTT value of the control group added only with virus (0.381±0.057), thus there was no cytotoxicity by extracts. However, in the case of leaves, the measured value is relatively lower than the MTT value of the control group, therefore it was concluded that stem (bark) is the most proper material as an antiviral agent.
Table 1: MTT Assay result according to the part of Alnus pendula
INDUSTRIAL APPLICABILITY
As described above in detail, the Alnus pendula extracts according to the present invention have a low toxicity in choriollantonic cell which is a normal cell, while having excellent antiviral effect. Therefore, the composition comprising Alnus pendula extracts can be used effectively in food and pharmaceutical composition since it is effective and safe in preventing and treating influenza virus diseases.
Although the present invention has been described in detail with reference to the specific features, it will be apparent to those skilled in the art that this description is only for a preferred embodiment and does not limit the scope of the present invention. Thus, the substantial scope of the present invention will be defined by the appended claims and equivalents thereof.