MXPA99010595A - Use of low-molecular-weight heparins for preventing and treating cerebral edemas - Google Patents

Abstract

The invention concerns the use of low-molecular-weight heparins for preventing and treating cerebral edemas.

Description

USE OF HEPARSNAS DS UNDER MOLECULAR WEIGHT FOR PRESSURE AND TRAINING OF CEREBRAL EDES Background of the invention: The present invention concerns the use of low molecular weight heparins for the prevention and treatment of cerebral edema. The invention also concerns the use of low molecular weight heparins for the preparation of a medicament useful for the prevention and treatment of cerebral edemas. Standard heparin is a sulfated polysaccharide, with an average molecular weight of 12,000 to 15,000 daltons, isolated from the intestinal mucus of the cow, sheep or pig. Heparin is used clinically for the prevention and treatment of rhomboembolic disorders, but sometimes causes bleeding. For about ten years, heparin has been progressively replaced by low-weight heparins molecular, which do not present, or present to a lesser degree, the inconvenience of causing bleeding; and they do not need more than one injection per day, instead of 2 to 3 injections per day for standard heparin. These low molecular weight heparins are prepared ? c. especially by means of fractionation, controlled depolymerization of heparin or by means of REF .: 31875 chemical synthesis. They have an anti Xa activity / anti-ally activity ratio greater than 2. It has now been found that low molecular weight heparins reduce cerebral edema. Cerebral edema is a serious consequence of cerebrovascular accidents, brain hemorrhages and central nervous system trauma (brain trauma and spinal cord trauma) but also of cardiac and / or respiratory arrest, or any other situation functional equivalent, whatever its origin. { ventricular fibrillation, malignant asthma crisis). Brain edema may also be found in any pathological or accidental situation of coma, accompanied by hypoperfusion of the brain parenchyma. Brain edema may also accompany brain tumors. Irradiations and bacterial, viral and parasitic infections of the cerebral parenchyma. According to the invention, a low molecular weight heparin having an average molecular weight of between 1000 and 10000 daltons, especially between 1500 and 6000 daltons and, in particular, between 4000 and 5000 daltons, is preferably used.

They can be prepared (low molecular weight heparins) by different procedures from heparin: - fractionation by means of solvents (FR2440376, US4692435); - fractionation on anionic resin (FR2453875) - gel filtration (BARRO CLIFFE, Throm. Res. 12, 27-36 (1977)); - Affinity chromatography (US4401758); - Depolymerization controlled by means of a chemical agent: nitrous acid (EP14184, EP37319, EP76279, EP623629, FR2503714, ÜS4804652, W0813276), ß elimination from an ester of heparin (EP40144, US5389618), periodate (EP287477), borohydride sodium (EP347588, EP380943), ascorbic acid (US 4533549); hydrogen peroxide (US4629699, US4791195), quaternary ammonium hydroxide from a quaternary ammonium salt of heparin (US4981955), alkali metal hydroxide (EP380943, EP347588) or enzymatically (EP64452, US4396762, EP244235, EP244236; US 4826827; US 3766167); by means of irradiation (EP 269981). Some can also be prepared by chemical synthesis (US4801583, US4818816, EP165134, EP84999, FR2535306). Among the low molecular weight heparins, there may be mentioned, more particularly, enoxaparin (INN), marketed by RHONE-POULENC RORER; nadroparin (DCI), marketed by SANOFI; Parnaparin (DCI), marketed by OPOCRIN-ALFA; the reviparina (DCI), marketed * by KNOLL; Dalteparin (DCI), marketed by KABI PHARMACIA; Tinzaparin (DCI), marketed by NOVO NORDISK; the danaparoid (DCI), marketed by ORGANON; Ardeparin (DCI), developed by WYETH AYERST; certoparin (DCI), marketed by SANDOZ and the products under study, such as compound CY222 from SANOFI-CHOAY (Thro b.Hamostasis, 58 (1), 553 (1987)), compound SR90107 / ORG315 0 from SANOFI-ORGANON (Thrombosis and Haemostasis, 74, 1468-1473 (1995)). Preferably, the low molecular weight heparins will be constituted by oligosaccharides having an acid 2 -O- s or 1-pentane or one of their ends. A particularly low molecular weight heparin is obtained by means of the depolymerization of ur. ester of heparin, by means of a base such as soda. A- The preventive action of the low molecular weight heparins on the edema has been determined in the rat after a brain injury according to the following protocol: the male rats of the Sprague Dawley strain (150 to 200 g ) (26 for the treated group and 22 for the control group) are anesthetized with chloral hydrate (400 mg / kg ip) and placed in stereotactic tension. The skin is made an incision to reveal the skull a cold light (Bioblock 150) and is placed in contact with the right side of the skull, in front of the lambda. The low molecular weight heparins are dissolved in a saline solution (NaCl 0.9%) and continue as follows: 3 hours before the lesion, heparin is injected, subcutaneously, 2 mg / kg / 5 mL. of low molecular weight; just before the lesion, 0.5 mg / kg / 5 mL, of the low molecular weight heparin and immediately afterwards, are injected intravenously, subcutaneously; 10 mg / kg / 5 L of pink bengal dye in a saline solution (0.9 of NaCl); The lesion is then performed by lighting the skull for 5 minutes, then the skin is sutured and the animals are placed in their cages; - 3 hours and 21 hours after the lesion, 2 mg / kg / 5 L of the low molecular weight heparin is injected subcutaneously; 24 hours after the injury, the animals are decapitated and the brains are recovered. Samples are recovered from the site of the lesion and in the contralateral site to the lesion using a 6 mm diameter bore in a float. The water volume of the samples is determined by means of the ratio of wet weight of the tissue / dry weight of the tissue and the edema expressed as the percentage of excess water over the injured sample, compared with a sample of the hemisphere with ralateral contour for each rat. The control animals received physiological saline under the same conditions. In this test, low molecular weight heparins reduced edema by approximately 30%. Enoxaparin reduced edema by 33%. These results show that low molecular weight heparins have a preventive effect on edema. B- The curative action of the low molecular weight heparins on the edema has been determined in rats, after photothrombotic brain injury according to the following protocol: the male rats of the Sprague Dawley strain (200 to 240 g) (20 for the control group and 12 and 8 for the treated groups) are anesthetized with chloral hydrate (400 mg / kg ip), and are placed in tension is erectotaxic. The skin is cut to reveal the skull and a cold light (Bioblock 150) is placed in contact with the right side of the skull, in front of the lambda. 10 mg / kg / 5 mL of pink bengal dye is injected intravenously into the physiological compartment. The skull is illuminated immediately for 5 minutes. The skin is sutured immediately. Low molecular weight heparins are dissolved in a saline solution (NaCl 0.9% d w 2 hours after the lesion, 0.5 mg / kg / 5 mL of the low molecular weight heparin are injected intravenously, then 15 minutes later, subcutaneously, 2 mg / kg / 5 mL of the heparin. low molecular weight, 6 hours after the lesion, 2 mg / kg / 5 mL of the low molecular weight heparin is injected subcutaneously. The animals are placed in their cages. 24 hours after the injury, the animals are decapitated and the brains are recovered. Samples are recovered from the site of the lesion and at the site contralateral to the lesion using a flotation drill, 6 mm in diameter. The volume of water is determined by the wet weight ratio of the tissue / dry weight of the tissue and the edema. is expressed as the percentage of excess water on the injured sample, compared to the contralateral hemisphere sample, for each rat. The control animals received physiological saline under the same conditions. In this test, low molecular weight heparins reduced edema by approximately 30%, when low molecular weight heparin is injected 2 hours or 6 hours after the injury. Enoxaparin reduced edema by 33% in the two cases.

In the same test, but where the low molecular weight heparins are injected 18 hours after the injury (0.5 mg / kg / 5 mL, intravenously, then 15 minutes later, 2 mg / kg / 5 mL, via subcutaneous), the edema reduction is still significant, because it is approximately 10 to 30% (enoxaparin, 23%, and nadroparin, 14%). These results demonstrate that low molecular weight heparins have a healing effect on edema.

C- The effect of low molecular weight heparins on cerebral edema is also demonstrated in the rat, on trauma-induced edema, according to the following technique: male rats of the Sprague Dawley strain (Charles River France), weighing 280 to 300 g (12 for the control group and 12 for the treated group), are anesthetized with halothane (1.5%), in a mixture N: 0/0 Í70 / 3C) and placed in stereotactic tension. The epicranium is cut and a hole is made by means of a toothed puncher, at the level of the parietal cortex 2C right. { coordinates: 1 3.5 mm anterior to 6 mm above the interaural line). A polyethylene tube of 3 mm inner diameter is placed on the hard mother, is fixed in the cranial cavity with dental cement and is connected to a solenoid valve Í5Danfoss Evsi 24v, 15w). r-, The hard mother remains intact. The valve is connected to an HPLC pump (Walters 590). The system is filled with sterile water and when the pump reaches a pressure of 3.8 to 4 bar, a fluid percussion of moderate severity (1.6 to 1.8 bar) is induced by a slight (20 ms) valve opening. The tube is removed immediately, the incision is sutured and the animals are placed in their cage, in a piece heated to a temperature of 26 to 28 ° C. Low molecular weight heparins, dissolved in saline (0.9% NaCl), are administered as follows: 2 hours after the injury: 0.5 mg / kg / 5 mL IV bolus; 2 hours 15 minutes after the injury: 2 mg / kg / 5 L SC; 6 hours after the injury: 2 mg / kg / 5 mL SC; 24 hours after the injury: 2 mg / kg / 5 mL SC; and 30 hours after the injury: 2 mg / kg / 5 mL SC. 5 mL / kg of saline solution (0.9% NaCl) are administered to the control group under the same conditions. The animals are sacrificed 48 hours after the injury. Cerebral edema is evaluated according to the wet weight / dry weight technique (24 hours at 100 ° C). Edema ealuates as the water content of the brain and is measured in the hippocampus and cortex adjacent to the site of injury. In this test, low molecular weight hepannas reduce edema in the hippocampus and cortex at least 40% adjacent to the site of injury.

Enoxaparin (LOVENOXR) reduced edema by 69% in the hippocampus, and 50% in the cortex adjacent to the site of injury. Medications consist of a salt (sodium or calcium), preferably) of a low molecular weight heparin in the form of a composition in which it is associated with any other pharmaceutically compatible product, which may be inert or physiologically active. The medicaments according to the invention can be used intravenously, subcutaneously, orally, rectally, topically or pulmonally (inhalation). Sterile compositions, for intravenous or subcutaneous administration, are generally aqueous solutions. These compositions may also contain adjuvants, in particular wetting agents, i s or t on i z a n t, emulsifiers, dispersants and are abilizers. The sterilization can be performed in various ways, for example, by aseptic filtration, incorporating sterilizing agents into the composition; by irradiation. They can also prepare er. form of sterile solid compositions, which can be dissolved in sterile water at the time of use, or any other sterile injectable medium. As solid compositions for oral administration, can. use tablets, pills, powders (gelatin capsules, tablets) or granules. In these compositions.

The active ingredient is mixed with one or several inert diluents, such as starch, cellulose, sucrose, lactose or silica, under a stream of argon. These compositions may also comprise substances additional to the diluents, for example, one or more lubricants such as magnesium stearate or talc; an agent that favors oral absorption; a colorant; a wrap (dragees); or a varnish. As liquid compositions for oral administration, pharmaceutically acceptable solutions, suspensions, emulsions, syrups and elixirs containing inert diluents, such as water, ethanol, glycerol, vegetable oils or paraffin oil can be used. These compositions may comprise substances additional to the diluents, for example, the humectants, sweeteners, thickeners, flavorings or stabilizers. Compositions for rectal administration are suppositories or rectal capsules which contain, in addition to the active product, excipients such as cocoa butter, semi-solid glycerides, or polyethylene glycols.

The compositions for topical administration can be, for example, creams, lotions, eye drops, mouthwash, nasal drops or aerosols. The doses depend on the effect sought, the duration of the treatment and the route of administration used; Generally they are between 0.2 mg and 4 mg per kg, per day, subcutaneously, or 14 to 280 mg per day, for an adult. In general, the doctor will determine the appropriate posology according to age, weight and any other factors appropriate to it. subject that is going to be treated. The present invention also concerns a method for the prevention or treatment of cerebral edema in man, which comprises the administration of an effective amount of a low molecular weight heparin. It is noted that, in relation to this date, the best method known by the applicant to carry out the aforementioned invention is the conventional one for the manufacture of the objects or substances to which it refers.

Claims (17)

1. CLAIMS Having described the invention as above, the content of the following claims is claimed as property: 1. The use of a low molecular weight heparin, characterized in that it is for the preparation of a useful medicine for the prevention and treatment of edema cerebral.
2. 2. The use, according to claim 1, characterized in that the low molecular weight heparin has an average molecular weight between 1,000 and 10,000 daltons.
3. 3. The use, according to claim 1, characterized in that the low molecular weight heparin has an average molecular weight between 1,500 and 6,000 daltons.
4. 4. The use, according to claim 1, characterized because the. Low molecular weight heparin has an average molecular weight between 4,000 and 5,000 daltons.
5. 5. The use according to any of claims 1 to 4, characterized in that the low molecular weight heparin is constituted by oligosaccharides having a 2-O-sulfo--opneuranesuronic acid at one of its ends.
6. 6. The use, according to any of claims 1 to 5, characterized in that the low molecular weight heparin is obtained by means of depolymerization of an ester of heparin, by means of a base.
7. 7. The use, according to any of claims 1 to 6, characterized in that the low molecular weight heparin is enoxaparin (DCI).
8. 8. The use, according to any of claims 1 to 4, characterized in that the low molecular weight heparin is nadroparin (DCI).
9. 9. The use, according to any of claims 1 to 4, characterized in that the molecular weight heparin is parnaparin (DCI).
10. 10. The use, according to any of claims 1 to 4, characterized in that the low molecular weight heparin is reviparin (DCI).
11. 11. The use according to any of claims 1 to 4, characterized in that the heparin of: a? Or molecular weight is daltepapne (DCI).
12. 12. The use, according to any of claims 1 to 4, characterized in that the low molecular weight heparin is tinzaparin (DCI).
13. 13. The use, according to any of claims 1 to 4, characterized in that the low molecular weight heparin is danaparoid (DCI).
14. 14. The use, according to any of claims 1 to 7, characterized in that the low molecular weight heparin is ardeparin (DCI).
15. 15. The use, according to any of claims 1 to 7, characterized in that the low molecular weight heparin is certoparin (DCI).
16. 16. The use, according to any of the rei indications 1 to 4, characterized in that the low molecular weight heparin is the compound CY222.
17. 17. The use, according to any of the rei indications 1 to 4, characterized in that the low molecular weight heparin is the compound SR90107 / ORG31540.