JPH07138156A - Immunosuppressive agent - Google Patents

Abstract

PURPOSE:To provide an immunosuppressive agent containing a terpene derivative as an active ingredient, low in toxicity, and little in side effects. CONSTITUTION:An immunosuppressive agent contains a compound of the formula (R<1>, R<2> a lower alkyl) as an active ingredient, and a medicinally acceptable carrier. The compound is called loliolide, contained in the plants of the Lolium tumulentum, algae such as the Phaeophyceae and the Phodophyceae, and plants such as Eucommia ulmoides used as a tea or a galenical, and obtained by extracting the plants. The agent may be prepared in the form of an oral administration preparation or a parenteral administration preparation and administrated at a dose of 0.01-100mg/kg/day in the case of the oral administration and at a dose of 0.001-10mg/kg/day in the case of the parenteral administration. Even when singly administrated, the agent can exhibit the immunosuppressive effect, but the simultaneous administration of the agent and a known immunosuppressive agent, cyclosporin, is also possible.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an immunosuppressive drug, and more particularly to an immunosuppressive drug with few side effects.

[0002]

2. Description of the Related Art The immune system maintains its homeostasis by interacting with immune cell groups having various functions such as T cells and B cells. The mechanism is precise, and when its delicate balance is disrupted, it leads to serious lesions. For example, diseases such as collagen disease, systemic lupus erythematosus, rheumatoid arthritis, and various allergic diseases are caused by the destruction of the control mechanism of immune cells, resulting in the production of antibodies against self or induction of excessive immune reaction. Disease. For the treatment of such diseases, an immunostimulant that enhances immunity is given in the former case, and an immunosuppressive agent that reduces immunity is used in the latter case. The present invention relates to the latter immunosuppressive agent, and as known immunosuppressive agents, cyclosporin A, mizoribine, azathioprine and the like are used, and these immunosuppressive agents include renal toxicity and bone marrow function suppression. Serious side effects are seen, which is a big problem.

[0003]

The present invention has been made in view of the above problems, and an object thereof is to provide a novel immunosuppressive agent having low toxicity.

[0004]

The immunosuppressive agent of the present invention comprises:
The following formula

[0005]

[Chemical 2]

(In the formula, R ¹ and R ² are the same or different and each represents a lower alkyl group.) A terpene derivative represented by the formula and a pharmaceutically acceptable carrier are included.

[0007]

First, the lower alkyl group used in R ¹ and R ² in the above formula means an alkyl group having 1 to 6 carbon atoms, and a preferable example thereof is a straight chain or branched chain aliphatic group. Hydrocarbon residues include, for example, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, neopentyl, hexyl and the like, more preferably when R ¹ and R ² are both methyl groups (the compound is It is called Lorioride).

[0008] One of the active ingredients of the present invention, loriolide is Loliumm perenne [R. Hodges e
t.al., Tetrahedron, 20, 1463-1467, 1964] plant;
Brown algae (Hondawara, Sargassum crassifolium) [M.
Kuniyoshi, Botanica Marina, 28, 501-503, 1985],
Red algae (Peyssonnelia caulifera) [Su, J
ingyu et al., Zhongguo Haiyang Yaowu, 11 (3), 1-3,
1992] and other algae; contained in plants such as Eucommia ulmoides O., which are used as tea and herbal medicine.

Examples of the method for preparing loriolide include the following methods. Tochu leaves were dried in the sun, 2 kg of the dried leaves were repeatedly extracted with 6 L of chloroform three times, and concentrated under reduced pressure to obtain 53 g of a chloroform extract. Next, this extract was subjected to normal-phase silica gel column chromatography, and 3 L of chloroform and a mixed solution of chloroform-methanol (97.
5: 2.5) Eluted with 3 L. The solvent was removed from this chloroform-methanol eluate under reduced pressure, and the product was further purified twice by high performance liquid chromatography (TSKgel OH-120) to obtain 20 mg of loriolide. Moreover, other terpene derivatives can be produced by a known lactone ring forming reaction.

As mentioned above, loriolide is widely contained in edible plants and the like, but side effects due to these plants have not been reported yet. In addition, when cytotoxicity of mouse spleen lymphocytes was examined, the IC _{50 of} cyclosporine A was 0.038 μg / ml, whereas the IC ₅₀ of loriolide was 20 μg / ml, and loriolide was cytotoxic. It turns out that is low. Furthermore, when an acute oral toxicity test was conducted using mice and rats, no death was observed even when 2 g / kg was administered.

The drug of the present invention can be provided in either oral or parenteral form, and an optimum dosage form can be selected according to the administration route, administration subject and the like. Examples of dosage forms suitable for oral administration include tablets, powders, granules, soft and hard capsules, sublingual agents, various liquids, and the like, and dosage forms suitable for parenteral administration include water-soluble suspensions and oil-based suspensions. Non-limiting examples are subcutaneous, intravenous or intramuscular injections such as preparations, drip infusions, suppositories in solid or suspension viscous liquid, and the like.

In formulating the immunosuppressive agent of the present invention, a surfactant, an excipient, a lubricant, an adjuvant and, if necessary, a pharmaceutically acceptable film-forming substance or coating aid are prepared according to a conventional method. A pharmaceutically acceptable carrier such as an agent can be used, and specific examples thereof will be given below.

In order to improve disintegration and dissolution in the digestive tract when the drug of the present invention is orally administered, surfactants such as alcohols, esters, polyethylene glycol derivatives represented by Tween 60 and polysorbate 80 are used. One or more of fatty acid esters of sorbitan and sulfated aliphatic alcohols can be added.

As the excipient, for example, sucrose, lactose, starch, crystalline cellulose, mannite, light anhydrous silicic acid, magnesium aluminate, magnesium metasilicate aluminate, synthetic aluminum silicate, calcium carbonate, sodium hydrogen carbonate. , Calcium hydrogen phosphate, carboxymethyl cellulose calcium and the like can be added alone or in combination of two or more.

As the lubricant, for example, magnesium stearate, talc, hardened oil and the like can be added alone or in combination of two or more. Salts, saccharin, sucrose, mannitol and orange are used as flavoring agents and flavoring agents. Oil, licorice extract, citric acid, glucose, menthol, eucalyptus oil,
A sweetening agent such as malic acid, a flavoring agent, a coloring agent, a preservative and the like may be contained.

Examples of adjuvants such as suspending agents and wetting agents can include coconut oil, olive oil, sesame oil, peanut oil, calcium lactate, safflower oil, soybean phospholipid, and the like. Examples of the film-forming substance include cellulose acetate phthalate (CAP), methyl acrylate / methacrylic acid copolymer, and methyl methacrylate / methacrylic acid copolymer.

When coating the above-mentioned film-forming substance, in addition to a commonly used coating aid such as a plasticizer, various additives for preventing mutual adhesion of chemicals during coating operation are added to form a film. It can improve the properties of the agent and make the coating operation easier. The active ingredient may be microencapsulated using a film-forming substance and then mixed with an excipient or the like to prepare a dosage form.

The dose of the drug of the present invention is an amount capable of exerting sufficient immunosuppressive ability depending on the degree of symptoms, the general condition of the patient, age, body weight, etc. The amount of loliolide, which is the active ingredient, is generally about 0.01 to 10 when orally administered, though it is determined as appropriate.
The range is 0 mg / kg / day, but preferably about 5 to 1
5 mg / kg / day. For parenteral administration, it is in the range of about 0.001 to 10 mg / kg / day, preferably about 0.5 to 1.5 mg / kg / day.

Although the immunosuppressive agent of the present invention can exert an immunosuppressive effect when administered alone, it can be co-administered with a known immunosuppressive agent such as cyclosporin A, which further suppresses immunosuppression. It is expected to enhance the action. Hereinafter, the present invention will be described in more detail with reference to examples, but the following examples do not limit the present invention.
All changes and modifications within the scope of the gist of the invention described below are included in the technical scope of the present invention.

[0020]

[Examples] Loriolide was selected as the compound used in this example, and the following formulation and experiment were conducted. Formulation Example 1 : Tablet A tablet having the following composition was prepared according to a conventional method. Loriolide 1 mg Lactose 76 mg Corn starch 20 mg Magnesium stearate 3 mg Silicic anhydride 100 mg

Formulation Example 2 : Capsule A capsule having the following composition was prepared according to a conventional method. Loriolide 1 mg Corn starch 289 mg Hydroxypropyl cellulose 8 mg Magnesium stearate 2 mg

Formulation Example 3 : Granules Granules having the following composition were prepared according to a conventional method. Loriolide 1 mg Mannitol 979 mg Hydroxypropyl cellulose 20 mg

Experimental Example 1 (Measurement of immunosuppressive activity) The immunosuppressive activity was examined by measuring the proliferation of lymphocytes isolated from the spleen of mice (RF Ashman, 'Fund.
amental Immunology 'ed. by WE Paul, Ravan Press,
New York, 267, 1984). That is, as the sample solution, the loriolide (5.0 μg / ml, 1
0.0μg / ml) and cyclosporin A (0.0125μg / ml), which is a conventional immunosuppressant, are used for each sample solution, and specific for the proliferation of lymphocyte suspension (2 × 10 ⁶ cells / ml) and T cells. Concanavalin A (10 μg
/ Ml) or by adding specifically stimulating lipopolysaccharide proliferation of B cells (20 [mu] g / ml), at 5% CO ₂ for 48 hours at 37 ° C., ³ the proliferation of T cells and B cells H-thymidine incorporation was measured as an index. The suppression rate of T cells and B cells was calculated as follows.

[0024]

[Equation 1]

[0025]

[Equation 2] The results are shown in Table 1.

[0026]

[Table 1]

For T cells, loriolide 5.0 μ
The inhibition rate was as low as about 11% in the g / ml addition group, but 1
The 0.0 μg / ml-added group showed a high inhibition rate of about 27%, which was significantly higher than that of the cyclosporin A-added group. On the other hand, with respect to B cells, the inhibition rate was 0 with cyclosporin A, whereas the inhibition rate was about 3% in the group containing 5.0 μg / ml of loriolide, and about 8% in the group containing 10.0 μg / ml. %, It was found that the inhibitory effect was seen. In the present invention, the above example was carried out by selecting loriolide, but the same effect can be obtained when other terpene compounds within the scope of the present invention are used.

[0028]

Since the method of the present invention is constructed as described above, it is possible to provide a novel immunosuppressive agent with low toxicity.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mitsuru Nino 1-25-14 Kannondai Tsukuba City, Ibaraki Prefecture Kobe Steel Works Tsukuba Research Area

Claims (1)

[Claims] 1. The following formula: (In the formula, R ¹ and R ² are the same or different,
An immunosuppressive agent comprising a terpene derivative represented by a lower alkyl group) and a pharmaceutically acceptable carrier.