DESCRIPTION OF THE PREFERRED EMBODIMENT

[0056] Applicants have discovered that organic extracts of certain edible plants or parts therefrom inhibit COX-2 activity. Applicants have also discovered that organic extracts of certain edible plants or parts therefrom selectively inhibit COX-2 activity. The inhibitory effect is selective because inhibition of COX-2 is greater than inhibition of COX-1. Consequently, organic extracts of the edible plants or parts therefrom may be used to selectively inhibit the activity of COX-2 in an organism without causing an equivalent inhibition of COX-1 activity. Advantageously, these organic extracts are nutraceuticals that may be safely consumed and provide an alternative to traditional drug-based therapy for COX-2 inhibition.

[0057] Accordingly, the organic extracts of the present invention preferably inhibit COX-2 activity more than COX-1 activity. Preferably, the inhibitory effect of the plant extract on COX-2 is at least about two times greater than its inhibitory effect on COX-1. In a particularly preferred embodiment, the inhibitory effect on COX-2 is at least about 10 times greater than the inhibitory effect on COX-1. COX enzyme inhibition and selectivity may be determined in accordance with any method generally known to those of ordinary skill in the field, as set forth in more detail below.

[0058] In addition to inhibiting COX-2, the organic extracts of the present invention are preferably isolated from an edible plant. As utilized herein, the term “edible” shall generally mean a substance consumed for the purpose of nourishment consisting of protein, carbohydrate (fiber or otherwise), fat and/or combinations thereof used in the body of an organism to sustain growth, repair and vital processes and to furnish energy. Classification of plants as edible versus non-edible, in addition to this general definition, is also based upon three primary criteria: (1) frequency of use as an edible substance; (2) availability in public commerce; and (3) toxicity limits due to potency. Therefore, the edible plant is preferably available to consumers in the region where the plant is provided in some form by lawful commerce. In addition, the edible plant preferably has a history of use which demonstrates that it may be safely consumed on a daily basis in amounts commonly employed in the indigenous culture where the edible plant is found for nourishment purposes. For example, a particular plant may be considered medicinal instead of edible if the plant is consumed by mouth for the purpose of correcting symptoms of illness (as opposed to nourishment) and is considered too potent to be consumed on a daily basis. Examples of edible plant uses include, but are not limited to: sources of starch, fruits, vegetables, spices, condiments, edible oils from plants, food coloring and other food additives, beverages, teas and tonics, sugar and other natural sweeteners, fermented beverages, ferments and enzymes, non-narcotic chewing leaves and gums, woody flavorings, and all other natural substances which are eaten or imbibed regularly to maintain health, sustain growth, repair injuries, and promote general well-being. In addition, any plant classified as edible by those of general skill in the art is included in the scope of the present invention, for example, such references include, NAPRALERT; Tyozaburo Tanaka, (Edited by Sasuke Nakoa) Tanaka's Cyclopedia of Edible Plants of the World, Keigaku Publishing Co., Tokyo, Japan, 1976; Stephen Facciola, Cornucopia II: A Source Book of Edible Plants, Kampong Publications, Vista, Calif., 1998; James A. Duke, Database of Phytochemical constituents of GRAS Herbs and Other Economic Plants, CRC Press, Boca Raton, Fla., 1992; and George Macdonald Hocking, Dictionary of Natural Products, Plexus Publishing, Inc., Medford, N.J., 1997. The contents of these references are hereby incorporated in their entirety.

[0059] In a particularly preferred embodiment, organic extracts are isolated from edible plants of the following plant orders: Agavales, Apocynales, Arales, Aristolochiales, Asterales, Brassicales, Cactales, Caryophyllales, Cucurbitales, Elaeagnales, Fagales, Gnetales, Graminales, Lamiales, Liliales, Malvales, Musales, Myrtales, Papaverales, Plantaginales, Polemoniales, Ranales, Rosales, Rubiales, Rutales, Scrophulariales, Umbellales, Urticales, and Violales. The ability of extracts isolated from edible plants of these particular orders to inhibit COX-2, to selectively inhibit COX-2, and their use as edible plants are set-forth below in Tables 1-24 and FIGS. 1-22.

[0060] It is to be understood that while applicant contemplates as within his invention the use of any organic extract isolated from edible plants wherein such extract inhibits COX-2 activity and preferably, wherein the inhibitory effect of such extract on COX-2 activity is greater than or equal to about 2 times greater than the inhibitory effect of the extract on COX-1 activity, that also included within applicant's contemplation are the use of such class or classes, but excluding any particular member(s) (e.g., species, genus or order) which may be previously disclosed and used and which inherently or otherwise possesses such required activity. For example, applicant's invention herein may include or exclude as appropriate, the full scope of the invention as related to Atractylodes lancea as set forth in applicant's U.S. application Ser. No. 09/272,363, which is fully incorporated herein by reference.

[0061] In order to prepare the organic extracts of the invention, an edible plant or parts thereof are preferably ground into a fine powder, the resultant powder is extracted with a solvent, and the extraction solvent is removed from the extract. The whole plant may be used or parts of the plant including an aerial part, fruit, leaf, stem, or root and any combination thereof may be utilized. If desired, the resultant extract may be further purified to yield a purified extract or one or more purified compositions. The grinding step may be accomplished by any commonly known method for grinding a plant substance. For example, the plant or parts thereof may be passed through a grinder to obtain a fine powder.

[0062] After the plant or parts thereof have been ground into a fine powder, they are combined with an extraction solvent. The solution is then stirred at a temperature, and for a period of time, that is effective to obtain an extract with the desired inhibitory effects on the activity of COX-2. The solution is preferably not overheated, as this may result in degradation and/or denaturation of compounds in the extract. The solution may be stirred at a temperature between about room temperature (25□ C) and the boiling point of the extraction solvent. Preferably, the solution is stirred at about room temperature.

[0063] The length of time during which the plant powder is exposed to the extraction solvent is not critical. Up to a point, the longer the plant powder is exposed to the extraction solvent, the greater is the amount of extract that may be recovered. Preferably, the solution is stirred for at least 1 minute, more preferably for at least 15 minutes, and most preferably for at least 60 minutes.

[0064] The extraction process of the present invention is desirably carried out using an organic solvent or a mixture of organic solvents. Organic solvents which may be used in the extraction process of the present invention, include but are not limited to hydrocarbon solvents, ether solvents, chlorinated solvents, acetone, ethyl acetate, butanol, ethanol, methanol, isopropyl alcohol and mixtures thereof. Hydrocarbon solvents which may be used in the present invention include heptane, hexane and pentane. Ether solvents which may be used in the present invention include diethyl ether. Chlorinated solvents which may be used in the present invention include dichloromethane and chloroform. Preferably, the solvent utilized for such extraction is a nonpolar organic solvent, such as dichloromethane or hexane.

[0065] The relative amount of solvent used in the extraction process may vary considerably, depending upon the particular solvent employed. Typically, for each 100 grams of plant powder to be extracted, about 500 ml of extraction solvent would be used. The organic solvent may be removed from the extract by any method known in the field of chemistry for removing organic solvents from a desired product, including, for example, rotary evaporation.

[0066] It is believed that the inhibitory effect of the plant extract of this invention on the activity of COX-2 is due to the presence of one or more compounds in the extract. Compounds present in the extract which inhibit the activity of COX-2 may be isolated and purified by those of ordinary skill in the art employing methods known in the art. For example, column chromatography and fractional distillation may be used to obtain pure compounds from the plant extract of this invention.

[0067] The isolation and purification of particular compounds from the organic plant extracts of this invention may be performed as described in Resch, et al., J. Nat. Prod., 61, 347-350 (1998), the entire contents of which are incorporated by reference herein. The methods disclosed therein may be used to isolate and purify compositions which inhibit COX-2.

[0068] The ability of a particular organic extract to inhibit COX-1 or COX-2 is preferably determined by performing COX activity assays utilizing recombinant COX-1 and COX-2. The COX-1 and COX-2 genes may be subcloned from a variety of organisms, however in a preferred embodiment such genes are isolated from human or murine sources, using a variety of procedures known to those skilled in the art and detailed in, for example, Sambrook et al., Molecular Cloning, A Laboratory Manual, 2nd ed., Cold Spring Harbor Laboratory Press, (1989) and Ausabel et al., Short Protocols in Molecular Biology, 3rd. ed., John Wiley & Sons (1995). Additionally, the subcloned portion of the particular COX gene may be inserted into a vector by a variety of methods. In a preferred method, the sequence is inserted into an appropriate restriction endonuclease site(s) in a baculovirus transfer vector pVL1393 utilizing procedures known to those skilled in the art and detailed in, for example, Sambrook et al., Molecular Cloning, A Laboratory Manual, 2nd ed., Cold Spring Harbor Laboratory Press, (1989) and Ausubel et al., Short Protocols in Molecular Biology, 3rd ed., John Wiley & Sons (1995).

[0069] The recombinant baculoviruses may be isolated by transfecting an appropriate amount of baculovirus transfer vector DNA into a sufficient quantity of SF9 insect cells along with linearized baculovirus plasmid DNA by the calcium phosphate method or any other method generally know to those skilled in the art. (See M. D. Summers and G. E. Smith, A Manual of Methods for Baculovirus Vectors and Insect Cell Culture Procedures, Texas Agric. Exp. Station Bull. 1555 (1987)). Recombinant viruses may be purified by three rounds of plaque purification and high titer (10⁷-10⁸ pfu/ml) stocks of virus may be prepared.

[0070] Preferably, for large scale production, cells may be infected in approximately 10 liter fermentors (0.5×10⁶/ml) with the recombinant virus stock such that the multiplicity of infection is greater than about 0.1. After several hours the cells are centrifuged and the cell pellet is homogenized in an appropriate buffer such as Tris/sucrose (50 mM/25%, pH 8.0). The homogenate may then be centrifuged at an appropriate speed and for an appropriate time (such as 10,000×G for 30 minutes) so as to cause the homogenate to separate into a pellet and supernatant fraction. The resultant supernatant fraction will contain the desired product and may be stored at −80□ C until use.

[0071] In order to test organic extracts for COX-2 inhibition and selectivity, standard COX-1 and COX-2 assays may be performed by employing ELISA procedures generally known to those skilled in the art. In such procedures, COX-1 and COX-2 activities are assayed as PGE₂ formed/μg protein/time using ELISA to detect the amount of PGE₂ synthesized from arachidonic acid. PGE₂ formation may be measured using PGE₂ specific antibody. Indomethacin, a non-selective COX-2/COX-1 inhibitor, may be employed as a positive control. The relative ability of various organic extracts to inhibit COX-1 or COX-2 at a particular concentration may be determined by comparing the IC₅₀ value expressed as μg extract/ml solvent resulting in a 50% inhibition of PGE2 production. Selective inhibition of COX-2 may then be determined by the IC₅₀ ratio of COX-1/COX-2. Additionally, any other means to determine COX inhibition known to those generally skilled in the art may be employed, for example, determining the ratio of percent inhibition of COX-1/COX-2 at a fixed concentration of test agent.

[0072] The extracts of this invention may be used to manage, prevent and/or treat an organism having, or at risk for developing, a condition which is mediated in whole or in part by COX-2. Accordingly, conditions which may be benefited by inhibition of COX-2 or selective inhibition of COX-2 include, but are not limited to, the treatment of inflammation in an organism, and for treatment of other inflammation-associated disorders, such as, an analgesic in the treatment of pain and headaches, or as an antipyretic for the treatment of fever. For example, extracts of the invention would be useful to treat arthritis, including but not limited to rheumatoid arthritis, spondyloarthopathies, gouty arthritis, osteoarthritis, systemic lupus erythematosus and juvenile arthritis. Such extracts of the invention would be useful in the treatment of asthma, bronchitis, menstrual cramps, tendinitis, bursitis, skin-related conditions such as psoriasis, eczema, burns and dermatitis, and from post-operative inflammation including ophthalmic surgery such as cataract surgery and refractive surgery. Extracts of the invention also would be useful to treat gastrointestinal conditions such as inflammatory bowel disease, Crohn's disease, gastritis, irritable bowel syndrome and ulcerative colitis, and treatment of cancer, including but not limited to the following types of cancer: colon, breast, prostate, bladder, or lung. In yet another preferred use, the extracts of the present invention may also be utilized as chemopreventive agents. Extracts of the invention would be useful in treating inflammation in such diseases as vascular diseases, migraine headaches, periarteritis nodosa, thyroiditis, aplastic anemia, Hodgkin's disease, sclerodoma, rheumatic fever, type I diabetes, neuromuscular junction disease including myasthenia gravis, white matter disease including multiple sclerosis, sarcoidosis, nephrotic syndrome, Behcet's syndrome, polymyositis, gingivitis, nephritis, hypersensitivity, swelling occurring after injury, myocardial ischemia, and the like. The extracts would also be useful in the treatment of ophthalmic diseases, such as retinitis, retinopathies, uveitis, ocular photophobia, and of acute injury to the eye tissue. The extracts would also be useful in the treatment of pulmonary inflammation, such as that associated with viral infections and cystic fibrosis. Additionally, the extracts would be beneficial for the treatment of certain central nervous system disorders such as cortical dementias including Alzheimer's disease. The extracts of the invention are useful as anti-inflammatory agents, such as for the treatment of arthritis, with the additional benefit of having significantly less harmful side effects. These extracts would also be beneficial in the treatment of allergic rhinitis, respiratory distress syndrome, endotoxin shock syndrome, atherosclerosis and central nervous system damage resulting from stroke, ischemia and trauma. Additionally, the extracts would be useful in the treatment of pain, including but not limited to postoperative pain, dental pain, muscular pain, and pain resulting from cancer.

[0073] The present extracts may also be employed either alone or in combination with other compounds as a part of combination therapy, partially or completely, in place of other conventional anti-inflammatories. For example, such as together with steroids, NSAIDs, 5-lipoxygenase inhibitors, leukotriene antagonists, LTA4 hydrolase inhibitors, and LTC4 synthase inhibitors. Preferably, with combination therapy, one will typically combine a drug or drugs and a nutraceutical, such as a plant extract of the current invention, in a manner such that the drug and the nutraceutical have different mechanisms of action, but yet target the same disease. For example, in a typical selection of agents for use in combination therapy to treat arthritis, one could utilize a plant extract of the present invention, which exhibits selective COX-2 inhibition with another agent known to attenuate inflammation associated with arthritis via an independent mechanism.

[0074] Those of ordinary skill in the art of preparing pharmaceutical formulations can readily formulate pharmaceutical compositions having plant extracts using known excipients (e.g., saline, glucose, starch, etc.). Similarly, those of ordinary skill in the art of preparing nutritional formulations can readily formulate nutritional compositions having plant extracts. And those of ordinary skill in the art of preparing food or food ingredient formulations can readily formulate food compositions or food ingredient compositions having plant extracts.

[0075] In addition, those of ordinary skill in the art can readily determine appropriate dosages that are necessary to achieve the desired therapeutic, prophylactic, pathologic or resuscitative effect upon oral, parenteral, rectal and other administration forms to the organism. Typically, in vivo models (i.e., laboratory mammals) are used to determine the appropriate plasma concentrations necessary to achieve a desired mitigation of inflammation related conditions.

[0076] The extracts of the present invention may be employed for the treatment and/or prevention of inflammation-related disorders, as identified above, in a number of organisms. Besides being useful for human treatment, these extracts are also useful for veterinary treatment of companion animals, exotic animals and farm animals, including mammals, rodents, avians, and the like. More preferred animals include horses, dogs, cats, sheep, and pigs.

[0077] The detailed description set-forth above is provided to aid those skilled in the art in practicing the present invention. Even so, this detailed description should not be construed to unduly limit the present invention as modifications and variation in the embodiments discussed herein can be made by those of ordinary skill in the art without departing from the spirit or scope of the present inventive discovery.

[0078] All publications, patents, patent applications and other references cited in this application are herein incorporated by reference in their entirety as if each individual publication, patent, patent application or other reference were specifically and individually indicated to be incorporated by reference.

[0079] Without further elaboration, it is believed that one skilled in the art can, using the preceding description, utilize the present invention to its fullest extent. The following preferred specific embodiments are, therefore, to be construed as merely illustrative, and not limitative of the remainder of the disclosure in any way whatsoever.

EXAMPLES

Sample Preparation

[0080] Plants or parts thereof were dried and sliced (“sample”). Samples of organic extracts were prepared from the edible plants listed in Table 1. The plant orders and families that the various samples were prepared from are also set forth in Table 1. In addition, details regarding the use of these plants as edibles is set-forth in Table 2. The particular sample was then ground into a fine powder using a coffee grinder. Approximately 100 grams of the resulting powder were added to approximately 500 ml of dichloromethane and stirred at room temperature for about 1 hour. The solvent was then removed by rotary evaporation, leaving several grams of the particular extract.

Inhibitory Effect of Various Plant Organic Extracts on COX-1 and COX-2 Activity

[0081] The particular extracts resulting from the sample preparation procedure detailed above were each evaluated for selective inhibition of COX-1 and COX-2. The COX-1 and COX-2 inhibition activities were determined in vitro according to the method of Gierse et al., J. Biochem., 305, 479-484 (1995). This method is summarized below.

[0082] Preparation of Recombinant COX Baculoviruses

[0083] Recombinant COX-1 was prepared by cloning a 2.0 kb fragment containing the coding region of human or murine COX-1 into a BamH1 site of the baculovirus transfer vector pVL1393 (Invitrogen) to generate the baculovirus transfer vectors for COX-1 according to the method of D. R. O'Reilly et al., Baculovirus Expression Vectors: A Laboratory Manual (1992).

[0084] Recombinant baculoviruses were then isolated by transfecting 4 μg of baculovirus transfer vector DNA into (2×10⁸) SF9 insect cells along with 200 μg of linearized baculovirus plasmid DNA by the calcium phosphate method. (See M. D. Summers and G. E. Smith, A Manual of Methods for Baculovirus Vectors and Insect Cell Culture Procedures, Texas Agric. Exp. Station Bull. 1555 (1987)). Recombinant viruses were purified by three rounds of plaque purification and high titer (10⁷-10⁸ pfu/ml) stocks of virus were prepared.

[0085] For large scale production, SF9 insect cells were infected in 10 liter fermentors (0.5×10⁶/ml) with the recombinant baculovirus stock such that the multiplicity of infection was 0.1. After 72 hours the cells were centrifuged and the cell pellet was homogenized in Tris/sucrose (50 mM/25%, pH 8.0) containing 1% of 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS). The homogenate was then centrifuged at 10,000×G for 30 minutes, and the resultant supernatant was stored at −80□ C until use.

[0086] Recombinant COX-2 was prepared by cloning a 2.0 kb fragment containing the coding region of human or murine COX-2 in accordance with the same method described above for COX-1.

[0087] Assay for COX-1 and COX-2 Activities

[0088] COX-1 and COX-2 activities were assayed as prostaglandin E2 (PGE2) formed/pg protein/time using ELISA to detect PGE2 synthesized from arachidonic acid. CHAPS-solubilized insect cell membranes containing recombinant COX-1 or COX-2 enzyme were incubated in a potassium phosphate buffer (50 mM, pH 8.0) containing epinephrine, phenol, and heme. Compounds or extracts were pre-incubated with the appropriate enzyme for approximately 10-20 minutes. Arachidonic acid (10 M) was then added to the mixture and the reaction was permitted to occur for ten minutes at room temperature (25□ C).

[0089] Any reaction between the arachidonic acid and the enzyme was stopped after ten minutes by transferring 40 ml of reaction mixture into 160 ml ELISA buffer and 25 M indomethacin. Indomethacin, a non-selective COX-2/COX-1 inhibitor, was utilized as a positive control. The PGE₂ formed was measured by standard ELISA technology utilizing a PGE2 specific antibody (Cayman Chemical).

[0090] Approximately 200 mg of each extract obtained from the sample preparation procedure set-forth above were each individually dissolved in 2 ml of dimethyl sulfoxide (DMSO) for bioassay testing to determine the COX-1 and COX-2 inhibitory effects of each particular extract. Potency was determined by the IC₅₀ value expressed as g extract/ml solvent resulting in a 50% inhibition of PGE2 production. Selective inhibition of COX-2 was determined by the IC₅₀ ratio of COX-1/COX-2. The results of these bioassays performed utilizing extract isolated from the plant variety indicated are reported in Tables 3-24 and FIGS. 1-22 delineated below.

[0091] Table 1 below sets forth results of screening extracts of edible plants isolated from the orders, families, genera, and species indicated. A primary screen (indicated as 1□ assay in Table 1) was performed in order to determine particular extracts that inhibit COX-2 at a concentration of 10 ug/ml. The extracts were then subjected to a confirmation assay to determine the extent of COX-2 inhibition at three different concentrations (10 ug/ml, 3.3 ug/ml and 1.1 ug/ml). The extracts were then tested for their ability to inhibit COX-1 at a concentration of 10 ug/ml. The percentage of COX inhibition compared to control is indicated as a percentage in each column, with a higher percentage indicating a greater degree of COX inhibition. In addition, the IC₅₀ value for COX-1 and COX-2 was also determined for certain extracts as indicated in Table 1. The selectivity for these extracts was then determined by the IC₅₀ ratio of COX-1/COX-2, as set-forth above. The COX-2 selectivity of extracts whose IC₅₀ value was not determined may be calculated by dividing the percentage of COX-2 inhibition (at a concentration of 10 ug/ml) by the percentage of COX-1 inhibition (at a concentration of 10 ug/ml). 1

[0092] The order, family, genus, and species of each plant whose extract was tested for COX-2 and COX-1 inhibitory activities are shown.

[0093] Table 2 below provides a description detailing the particular edible use of each plant extract tested for COX-2 inhibition as set-forth in Table 1. The plants are listed alphabetically according to genus. In addition, a comprehensive listing of references known to those generally skilled in the art is provided that details the edible consumption of these plants. 2