The present invention relates to a pharmaceutical composition intended for the prevention or for the treatment of cerebral oedema.
Cerebral oedema is characterised as being an excessive accumulation of water in the intra- and/or extracellular compartments of the brain (Pollay (1996) In Neurosurgery, 2nd ed. Mc Graw Hill Book Co., New York, 335-344). Cerebral oedema may be of neurological origin, as in the cases of ischaemic attacks, intracerebral haemorrhages, brain tumours, cases of meningitis or of encephalitis, or of non-neurological origin, as in cases of diabetic ketoacidosis, lactic acidosis, hypertensive encephalopathy, malignant hypertension, hyponatraemia or an effect of high altitude.
The principal consequence of cerebral oedema is an increase in the intracranial fluid pressure, leading to a reduction in the blood supply to the brain and the partial or total destruction of insufficiently vascularized cerebral tissues.
Few compounds are available for the pharmacological treatment of cerebral oedemas, and among the most commonly used the following compounds may be mentioned:
Moclobemide is a benzamide derivative which inhibits type A monoamine oxidase in a reversible manner and which is currently used as an antidepressant. Few undesirable side effects following its use are documented.
The synthesis of this compound and of certain of its derivatives is described in the U.S. Pat. No. 4,210,754. Moreover, numerous metabolites of moclobemide have been identified (Jauch et al. (1990) Acta Psychiatr. Sand. Suppl. 360:87-90); these metabolites are characterised in particular by a hydroxylation of the phenyl group or by C or N oxidations of the morpholine group.
The object of the present invention is to provide novel compounds which do not have the drawbacks of the compounds which are already known, within the framework of the prevention or of the treatment of cerebral oedema.
In order to achieve this, the present invention derives from the discovery by the inventors that moclobemide allows the prevention or the treatment of cerebral oedema.
Therefore the present invention relates to the use of at least one compound of formula (I) below:
in which:
The term “cerebral oedemas” is used to denote the conditions in which there is an excessive accumulation of water in the intra- and/or extracellular compartments of the brain. Cerebral oedemas are described in particular in Pollay (1996) In Neurosurgery, 2nd ed. Mc Graw Hill Book Co., New York, 335-344.
The synthesis of the above compounds is described in the U.S. Pat. No. 4,210,754, or can be easily deduced by the person skilled in the art on the basis of this same document.
It is possible to verify the activity of prevention or of treatment of cerebral oedema of the compounds of formula (I) above, for example in an animal model, such as the rat, by measuring, after sacrifice, the significant decrease in the percentage of water in the brain of animals which have received triethyltin and have been treated with the compounds of formula (I), by comparison with animals which have received triethyltin and not been treated. This test, described by Linee et al., 1984 Ann. Pharm. Fr. 42, 431-442, is carried out in the examples.
Advantageously, the compounds of formula (I) above are capable of acting, in particular by inhibiting type A monoamine oxidase, according to a process different from that implemented by the compounds usually used within the framework of the treatment of cerebral oedema and therefore do not have their detrimental effects.
In a particular embodiment of the use as defined above of a compound of formula (I), NR1 represents a heterocycle selected from the list comprising:
In another particular embodiment of the use as defined above of a compound of formula (I), b represents 1 and X represents O.
In another particular embodiment of the use as defined above of a compound of formula (I), n=2 and the alkyl chain —(CH2)n— is not substituted.
In a preferred embodiment the invention also relates to the use as defined above of a compound of formula (I) represented by the following formula (II):
in which R2, R3, R4, R5 and R6 are as defined above, with the proviso that at least one of R2, R3, R4, R5 and R6 represents a halogen atom.
In another preferred embodiment the invention also relates to the use as defined above of a compound of formula (I) represented by moclobemide, of the following formula (III):
According to a particular embodiment of the use as defined above, the cerebral oedema is following a cerebral vascular accident, a cerebral trauma, a cerebral tumour, cerebral metastases of a cancer, a cerebral abscess, a hypertensive attack, a diabetic ketoacidosis or a neuropaludism.
According to a preferred embodiment of the use as defined above, the medicament is suitable for administration to an individual requiring a unitary dose thereof of approximately 5 mg to approximately 900 mg, in particular approximately 150 mg to approximately 450 mg of the compound of formula (I).
According to another preferred embodiment of the use as defined above, the medicament is suitable for administration to an individual requiring a dose thereof of approximately 5 mg/day to approximately 900 mg/day, in particular approximately 150 mg/day to approximately 450 mg/day of the compound of formula (I).
According to another preferred embodiment of the use as defined above, the medicament is suitable for oral, intravenous, intramuscular or rectal administration.
According to yet another preferred embodiment of the use as defined above, the medicament is presented in the form of tablets, capsules, powder, sachets, suppositories, sugar-coated pills, syrups, suspensions or solutions.
In another particular embodiment of the use as defined above, the compound of formula (I) is associated with at least one additional compound intended for the prevention or for the treatment of cerebral oedema, such as a compound selected from the list comprising a corticoid, in particular a glucocorticoid, glycerol, mannitol, a diuretic, in particular furosemide, a barbiturate, tetracosactide, an antibiotic, CDP-choline (cytidine 5′-diphosphocholine), vinpocetine, a calcium inhibitor and an NMDA (N-methyl-D-aspartate) antagonist.
Advantageously, the association of a compound of formula (I) with an additional compound indicated in the treatment of cerebral oedema makes it possible to reduce the dose or the duration of administration of the said additional compound and thus to limit the side effects thereof.
The present invention also relates to a pharmaceutical composition comprising by way of active substance at least one compound of formula (I) as defined above, or a pharmaceutically acceptable salt thereof, and at least one additional compound intended for the prevention or for the treatment of cerebral oedema, such as a compound selected from the list comprising a corticoid, in particular a glucocorticoid, glycerol, mannitol, a diuretic, in particular furosemide, a barbiturate, tetracosactide, an antibiotic, CDP-choline, vinpocetine, a calcium inhibitor, an NMDA antagonist, in association with a pharmaceutically acceptable vehicle.
The present invention also relates to products containing:
The star symbol (*) shows a significant difference with respect to the groups without treatment (p<0.05, ANOVA).
The star symbol (*) represents a significant difference with respect the respective control groups (p<0.05, ANOVA).
The star symbol (*) represents a significant difference with respect to the respective control groups (p<0.05, ANOVA).
The rats receive neither TET nor moclobemide (white column), TET in the absence of moclobemide (black column), moclobemide at the rate of 50 mg/kg 2 times per day in the absence of TET (vertically hatched column), or TET (3 mg/kg/day) in the presence of moclobemide at the rate of 50 mg/kg 2 times per day (diagonally hatched column). The star symbol (*) represents a significant difference with respect to the respective control groups (p<0.05, ANOVA).
The rats receive neither TET nor moclobemide (white column), TET in the absence of moclobemide (black column), moclobemide at the rate of 100 mg/kg 2 times per day in the absence of TET (vertically hatched column), or TET (3 mg/kg/day) in the presence of moclobemide at the rate of 100 mg/kg 2 times per day (diagonally hatched column).
The star symbol (*) represents a significant difference with respect to the respective control groups (p<0.05, ANOVA).
The inventors have demonstrated a protection of the moclobemide on cerebral oedema induced by triethyltin (TET) chloride. Moreover, the effect of moclobemide has also been studied on the disruptions induced by TET for the 3 following parameters: weight development, neurological index and ambulatory activity.
1. Material and Methods
1.1. Model
Cerebral oedema induced triethyltin (TET) chloride in the rat is a physiopathological model for the study of substances recommended in the treatment of certain cerebrovascular ailments (Linee et al., 1984 Ann. Pharm. Fr. 42, 431-442). Intoxication with TET is also a useful toxicological tool for testing products which act at the cerebral level in the elderly person for testing new products in senescence (Bentue-Ferer et al., 1985 Exp. Aging Res. 11, 137-141)
Cerebral oedema due to TET is a chronic oedema, appearing progressively and spontaneously reversible on condition that the intoxication is stopped. This oedema develops exclusively at the level of the brain and of the spinal cord. Cerebral oedema is characterised by an increase in the contents of water, sodium and chlorides without significant modification of the potassium content. The oedema is reflected in a specific attack on the white matter (Naruse et al., 1982 J. Neurosurg. 56, 747-752), with a widening of the intramyelinic spaces and attack on the myelin (Kirschner and Sapirstein, 1982 J. Neurocytol. 11, 559-569). The myelin of the central nervous system has the potential to recover its integrity after oedematous damage by the withdrawal of the accumulated fluid (Yanagisawa et al., 1990 Neurochem. Res. 15, 483-486). The scale of the oedema, which is accompanied by a weight loss and peripheral neurological disorders, is proportional to the dose of TET.
It has been demonstrated in particular that:
According to a preventive protocol, the substances to be tested are administered during the intoxication with tin and their activities are measured after 5 days. Under these conditions, it has been shown that certain cerebrovascular medicaments are active, such as dihydroergotoxin, (−)eburnamonine and vincamine (Linee et al., 1984 Ann. Pharm. Fr. 42, 431-442).
1.2. Animals
Male Wistar rats from Janvier weighing between 200 and 250 grams at the start of the experiment, are utilised after at least 7 days of acclimatisation in the animal house (room temperature=22±2° C.; relative humidity=50±20%; nutrition UAR “A04”; nycthemeral cycle (12 h/12 h (7.00 a.m.-7.00 p.m./7.00 p.m.-7.00 a.m.)).
1.3. Experimental Protocol
The protocol was adapted according to Linee et al. (Linee et al., 1984 Ann. Pharm. Fr. 42, 431-442):
Water Content of the Brain
Neurological Index: According to the Following 4 Criteria
Ambulatory Activity
The motor activity is detected with the aid of 15 photoelectric cells distributed over the walls of the rectangular compartment (320×290×100 mm) of the Opto-Varimex system from Colombus Instruments U.S.A.
The number of displacements (ambulatory activities, horizontally and vertically) of the animal is counted for 15 minutes. The activity is expressed in arbitrary units: 1 unit corresponds to a passage in front of a photoelectric cell.
1.5. Product
The triethyltin bromide at 97% (Sigma, ref 288047) is diluted in distilled water.
The moclobemide (Biocodex) is placed in suspension in Tween 80 at 1% (0.5 ml/100 g).
1.6. Statistics
The statistical test utilised is the analysis of variance. When the result does not depend upon chance (to 5%), the groups treated which differ from the control group are determined.
2. Results
2.1. Effect of the Dose of Triethyltin
Several doses of TET were studied in order to determine a dose enabling reproducible results to be obtained.
The administration of TET at 2 mg/kg/day orally has little effect at the level of the development of the body weight of the rats, and at the level of neurological index.
The administration of TET at 3 mg/kg/day causes a decrease in the body weight of the rats and signs of neurological toxicity from the 4th day, but no mortality.
The administration of TET at 4 mg/kg/day leads to signs of neurological toxicity from the 2nd day, and of mortality from the 4th day.
Consequently, the dose of 3 mg/kg/day was chosen for the following studies.
2.2. Effect of Moclobemide
Cerebral Oedema
The administration of moclobemide alone at 2×50 or 2×100 mg/kg/day for 5 days does not modify the percentage of water in the brain in the rat (Table 1 and
TET at 3 mg/kg/day, for 5 days, leads to a significant increase in the percentage of water, from 79.75% and 79.65% respectively for the two control groups, to 81.40% and 81.26% respectively for the two groups treated, indicating the presence of a cerebral oedema.
The concomitant administration of moclobemide at 2×50 mg/kg/day and TET does not suppress the significant increase in the percentage of water induced by the TET. On the other hand, at the dose of 2×100 mg/kg/day, the moclobemide inhibits the effect of the TET on the percentage of water.
Body Weight
At the level of the development of the body weight of the rats, TET leads to a significant drop in weight at day 4 (Table 2 and
Moclobemide administered alone disrupts the weight gain. At the 2 doses utilised, the body weight of the rats is significantly lower at day 4 relative to the control groups.
However, in the presence of TET and of moclobemide at 2×50 mg/kg/day, it is noted that the body weight of the rats at day 4 has not decreased as much as that of the group receiving only TET. In this case, the moclobemide partially prevents the drop in weight induced by the TET.
In the presence of TET and of moclobemide at 2×100 mg/kg/day, it may be noted that the drop in weight observed between day 3 and day 4 in the group receiving only TET is not produced. Therefore moclobemide prevents the drop in weight induced by the TET.
Neurological Index
The administration of moclobemide at 2×50 or 2×100 mg/kg/day for 5 days does not lead to any behavioural sign in the rat (Table 3 and
TET at 3 mg/kg/day, for 5 days, leads to a significant increase in the neurological index from day 3, with a much stronger effect at day 4, indicating substantial neurological troubles.
The concomitant administration of moclobemide at 2×50 mg/kg/day and of TET greatly reduces this neurological index at day 3, and reduces it by half at day 4.
At the dose of 2×100 mg/kg/day, moclobemide also inhibits the effect of TET.
Ambulatory Activity
The administration of moclobemide at 2×50 mg/kg/day for 5 days does not lead to any significant effect on the ambulatory activities in the rat (Table 4 and
On the other hand, at the dose of 2×100 mg/kg/day, the administration of moclobemide significantly decreases the ambulatory activities at day 4 (Table 5 and
TET at 3 mg/kg/day, for 5 days, leads to a great decrease in the ambulatory activities at day 4, with and almost total inhibition of the vertical ambulatory activity.
The concomitant administration of moclobemide at 2×50 or 2×100 mg/kg/day and of TET does not suppress the effect of TET, but reduces it partially at the level of the vertical ambulatory activity.
Neurological index:
0 → no apparent anomaly
1 → loss of spontaneous activity: the rat does not leave a limited surface in a period of 60 seconds, but it escapes normally if it is stimulated (noise, pinching); it has lost its exploratory activity but retains its motor capacities
2 → loss of the gripping reflex when the rat is pushed on the surface
3 → loss of the retreat reflex, coma followed in the majority of cases by death
Number | Date | Country | Kind |
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05 05691 | Jun 2005 | FR | national |