The present invention relates to pharmaceutical and diagnostic compositions as well as to the use of the active substances contained therein for producing a pharmaceutical or a diagnostic composition for the treatment or diagnosis of neurodegenerative disorders or amyloid diseases.
Various documents are cited in the text of the present description. The disclosure content of the cited documents (including all manufacturer descriptions, information etc.) is herewith incorporated by reference into the present description.
In the prior art, small chemical compounds were identified which can inhibit the aggregation of polyglutamine-containing proteins or amyloid-forming proteins. Patent applications directed to these compounds were filed (Wanker, E. E., Heiser, V., Lehrach, H., Broeker, W., Dunkel, I., Böttcher, H., Barnickel, G., Herhaus, C. (2001) “Inhibitors of PolyQ-Aggregation” EP 01105088.7 and Wanker, E. E., Sittler, A. and Hartl, U. (2001) “Novel compounds useful in the prevention or treatment of diseases associated with protein aggregation and amyloid formation” EP 0110769.5). Excerpts of these inventions and other relevant results were published (Heiser, V., Scherzinger, E., Boeddrich, A., Nordhoff, E., Lurz, R., Schugardt, N., Lehrach, H. and Wanker, E. E. (2000) Proc Natl Acad Sci USA. 97, 6739-6744; Heiser, V., Engemann, S., Brocker, W., Dunkel, I., Boeddrich, A., Waelter, S., Nordhoff, E., Lurz, R., Schugardt, N., Rautenberg, S. et al., (2002) Proc Natl Acad Sci USA, 99 Suppl 4, 16400-16406 and Sittler, A., Lurz, R., Lueder, G., Priller, J., Hayer-Hartl, M. K., Hartl, F. U., Lehrach, H. and Wanker, E. E. (2001), Hum Mol Genet, 10, 1307-1315.).
Other working groups as well described positive effects of chemical compounds on the aggregate formation in Huntington's chorea (Ferrante, R. J., Andreassen, O. A., Dedeoglu, A., Ferrante, K. L., Jenkins, B. G., Hersch, S. M. and Beal, M. F. (2002) J. Neuroscience 22, 1592-1599, Dedeoglu, A. et al. (2002), J. Neuroscience 22, 8942-8950 and Keene, C. D., Rodrigues, C. M. P., Eich, T., Chhabra, M. S., Steer, C. J. and Low, W. C. (2002) Proc. Natl. Acad. Sci. USA 99, 10671-10676).
Furthermore, several small molecules were described which inhibit the aggregation of the amyloid β-peptide relevant for Alzheimer's disease. This includes the following publications: Lashuel, H., Hartley, D. M., Balakhaneh, D., Aggarwal, A., Teichberg, S. and Callaway, D. J. E. (2002), J. Biol. Chem. 277, 42881-42890; Merlini, G., Ascari, E., Amboldi, N., Bellotti, V., Arbustini, E., Perfetti, V., Ferrari, M., Zorzoli, I., Marione, M. G., Garini, P. et al. (1995), Proc. Natl. Acad. Sci. USA 92, 2959-2963; Salomon, A. R., Marcinowski, K. J., Friedland, R. F. and Zagorski, M. G. (1996) Biochemistry 35, 13568-13578; Lorenzo, A. and Yankner, B. A. (1994), Proc. Natl. Acad. Sci. USA 91, 12243-12247; Tomiyama, T., Shoji, A., Kataoka, K., Suwa, Y., Asano, S., Kaneko, H., Endo, N. (1996), J. Biol. Chem. 271, 6839-6844; Howlett, D. R., Perry, A. E., Godfrey, F., Swatton, J. E., Jennings, K. H., Spitzfaden, C., Wadsworth, H., Wood, S. J. and Markwell, R. E. (1999) Biochem. J. 340, 283-289; Luo, Y. et al. (2002), Proc. Natl. Acad. Sci. USA 99, 12197-12202; J., E. and Lee, M. (2003) Biochem. .Biophys. Res. Comm. 303, 576-579 and the publication by Howlett, D. R., George, A. R., Owen, D. E., Ward, R. V. and Markwell, R. E. (1999) Biochem. J. 343, 419-423. These and other relevant results include the three U.S. Pat. Nos. 6,001,331; 5,972,956 and 5,955,472, the patents WO 9628471, WO 9832754-A, JP 090954222, EP 1018511 and the patent SKF-74652.
Other approaches to the treatment of Alzheimer's disease include preventing the formation of pathological amyloid β-aggregates by using peptides (in this connection, cf. Soto C. (1999), Rev. Mol. Med. 5; 343-350).
For the treatment of spinocerebellar ataxia (type 3) the use of small molecules was described by Shirasaki H, Ishida C, Nakajima T, Kamei H, Koide T, Fukuhara N. (2003) [A quantitative evaluation of spinocerebellar degeneration by an acoustic analysis—the effect of taltirelin hydrate on patients with Machado-Joseph disease] Rinsho Shinkeigaku 43, 143-148 and Sakai, T. (1996) [A possibility of therapeutic trial with tetrahydrobiopterin, which was suggested by the administration of sulfamethoxazole-trimethoprim] Rinsho Shinkeigaku 12, 1324-1325.
Furthermore, additional patents and scientific publications are relevant with respect to the catechins of green tea. For instance, several patents have been granted or applied for which are directed to the ingredients of green tea. The U.S. patent 20020151506 (“Catechins for the treatment of fibrillogenesis in Alzheimer's disease, Parkinson's disease, systemic AA amyloidosis and other amyloid disorders”), U.S. patent 20020086067 (“Catechins and green tea extract for the treatment of amyloidosis in Alzheimer's disease and other amyloidoses”) are especially relevant. An examination of the delivery of the catechins of green tea to the brain was described by Yoshida, H. et al. (1999) Biochemical Pharmacology, 58, 1695-1703. Levites et al. described a neuroprotective effect of EGCG on neuroblastoma cells that had been damaged with the Alzheimer peptide amyloid β-peptide (Levites, Y., Amit, T., Mandel, S. and Youdim, M. B. H. (2003) FASEB J. 17, 952-954). The application of the catechins of green tea was not explicitly described and protected for polyglutamine disorders. However, we were able to observe a visible effect in disease models of polyglutamine disorders and would therefore like to seek protection for the application specifically for this group of disorders.
Many of the known compounds are not aimed at a direct interaction with the aggregate-forming proteins but to an indirect interaction, e.g. via heat shock proteins (HSPs). However, it is more useful to influence the formation of aggregates directly since according to current knowledge, they play an essential role in the development of the disease in the case of most disorders. Furthermore, an approach with chemical agents is superior to one with peptides since the latter are generally not delivered to the brain in an efficient manner and, most of the time, also decompose very quickly.
To sum up, it has to be noted that to this date disorders wherein the pathological deposit of proteins is part of the essential disease mechanisms can to a large extent only be treated symptomatically. There is therefore a demand for additional or more effective treatment options for these disorders.
It was therefore the object of the present invention to provide means and methods for the treatment and diagnosis of neurodegenerative disorders and amyloid diseases.
This object is achieved by the provision of the embodiments characterized in the claims.
Consequently, the present invention relates to a pharmaceutical or diagnostic composition comprising one or more active substances wherein the one or more active substance(s) is/are selected from a group consisting of:
The mentioned single- or multi-branched or straight-chain alkyl or heteroalkyl groups comprise 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 carbon atoms. The ring or ring systems possible in groups R1 to R9 and S1 to S3 in turn comprise 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 carbon atoms so that the mentioned groups can comprise a total of up to 20 carbon atoms, whereby any number lower than 20 is specifically envisaged as well. However, it is especially preferred that the number of carbon atoms in groups R1 to R9 and S1 to S3 does not exceed a total of 10. Again, any number lower than 10 is specifically envisaged as well.
The person skilled in the art is familiar with the term “heteroatom”. In this context, the term particularly refers to, but is not limited to, N, O, Cl, F, Br, I and S. It is preferred that the heteroatoms be present in the form of amides, esters, nitrites and ether compounds.
All the active substances or chemical agents inhibit the aggregation of proteins relevant to a disease which in the case of certain diseases, also known in the prior art as “amyloid diseases”, are deposited in the form of amyloids. These diseases include in particular neurodegenerative disorders.
The active substances or chemical agents are suitable for both the diagnosis and the treatment of these disorders. Within the framework of the present invention, the term “active substance” is also used in connection with diagnostic compositions. This is because binding of the active substance to amyloids or aggregates has to occur to allow a positive diagnosis of an amyloid or aggregate formation. This binding is subsumed under the term “effect”. In other words, the term “effect” is not restricted to a therapeutic effect.
The conversion of the protein-containing deposits to a form that can be broken down more easily by the organism by means of small molecules or the prevention of the formation of protein aggregates are possibilities of preventing these disorders, slowing their progress or even leading to an improvement and the disappearance of the symptoms. The active substances or chemical agents we identified have the potential of affecting the protein aggregation accordingly. They are not only useful for a therapeutic application or the development thereof but they can also potentially be used for the diagnosis or the evaluation of the progress of diseases based on the pathological deposit of proteins.
The invention offers several advantages compared to known pharmaceutical compositions and methods of treatment:
The active substances contained in the pharmaceutical and diagnostic compositions according to the present invention can be used as such or after their pharmacological properties have been improved.
Accordingly, the present invention also encompasses pharmaceutical and diagnostic compositions whose above-mentioned active substances have been subjected to an improvement of their pharmacological properties. For this purpose, the molecular scaffold of the active substance is modified further in order to obtain a modified binding site, a modified activity spectrum, a modified organ specificity, an improved activity, a reduced toxicity (an improved therapeutic index), reduced side-effects, a delayed onset of the therapeutic effectiveness or the duration of the therapeutic effectiveness, modified pharmacokinetic parameters (resorption, distribution, metabolism or excretion), modified physicochemical parameters (solubility, hygroscopic properties, color, taste, smell, stability, state of matter), an improved general specificity, organ or tissue specificity, and/or an optimized form and route of administration. This can be achieved by the esterification of carboxy groups, hydroxy groups with carboxylic acids, hydroxy groups to e.g. phosphates, pyrophosphates, sulfates, “hemisuccinates” or the formation of pharmaceutically acceptable salts, pharmaceutically acceptable complexes or the synthesis of pharmacologically active polymers, or the introduction of hydrophilic groups, the introduction and/or the replacement of substituents in aromatics or side chains, the alteration of the substituent pattern or the modification by introducing isosteric or bioisosteric groups, or the synthesis of homologous compounds, and/or the introduction of branched side chains, the conversion of alkyl substituents to cyclic analogues, the derivatization of hydroxy groups to ketals or acetals, the N-acetylation to amides, phenyl carbamates, the synthesis of Mannich bases and/or imines, or the conversion of ketones, aldehydes in Schiff bases, oximes, acetals, ketals, enol esters, oxazolidines, thiazolidines or combinations thereof.
The different measures described above are generally known. They include or are based on quantitative analyses of structure-activity relationships (QSAR); cf. Kubinyi, “Hausch-Analysis and Related Approaches”, Publishing House VCH, Weinheim 1992, as well as combinatory (bio)chemistry, classical chemistry and other approaches; cf. e.g. Holzgrabe and Bechtold, Deutsche Apotheker Zeitung 140(8) (2000), 813-823.
In a preferred embodiment of the pharmaceutical or diagnostic composition, the halogen atoms are selected from a group consisting of I, Cl, Br or F.
F is particularly preferred.
In a preferred embodiment of the pharmaceutical or diagnostic composition, the alkyl, heteroalkyl, aryl or heteroaryl groups comprise 1, 2, 3 or 4 heteroatoms each.
In a preferred embodiment of the pharmaceutical or diagnostic composition, the heteroatoms are selected from a group consisting of N, O, or S.
In a preferred embodiment of the pharmaceutical or diagnostic composition, the alkyl, heteroalkyl, aryl or heteroaryl groups comprise 1, 2, 3 or 4 substituents each.
In an especially preferred embodiment of the pharmaceutical or diagnostic composition, the substituents are selected from a group consisting of Cl, F, Br or I.
In a preferred embodiment of the pharmaceutical or diagnostic composition, R1 and R2, R2 and R3, R3 and R4, R4 and R5, R5 and R6, R6 and R7, R7 and R8 and/or R8 and R9 are bridged via further atoms.
In a preferred embodiment of the diagnostic composition, the active substance or at least one of the active substances is labeled. The labeling is preferably a radioactive labeling.
The binding to aggregates or amyloids as well as the binding site in the organism or a sample taken from the organism can be detected by means of imaging processes, in the case of radioactive-labeled active substances for example by means of the PET process (positron emission tomography) mentioned above. The process can be carried out in vitro, ex vivo or in vivo.
The possible nuclides are known to the person skilled in the art. They are usually short-lived nuclides with a preferred half-life between 20 minutes and 2 hours which can be prepared in a cyclotron.
The present invention also relates to the use of one or more of the active substances described above for preparing a pharmaceutical or diagnostic composition for the treatment or diagnosis of neurodegenerative disorders or amyloid diseases.
The terms “amyloid” and “amyloid disease” are known to the person skilled in the art. Amyloid is defined by three classical parameters which are used individually or in combination to detect amyloids and thus the presence of amyloid diseases:
Selected indications which fall under the definition “amyloid diseases”, and how they are diagnosed for example in clinical medicine, are described in more detail below.
In a preferred embodiment of the pharmaceutical composition, the diagnostic composition or the use, the pharmaceutical or diagnostic composition comprises, in addition to the active substance, one or more pharmaceutically acceptable carriers, diluents or excipients.
Examples of suitable pharmaceutically acceptable carriers and/or diluents are known to the person skilled in the art and include e.g. phosphate-buffered sodium chloride solutions, water, emulsions, such as e.g. oil/water emulsions, different types of wetting agents or detergents, sterile solutions, etc. Pharmaceutical compositions comprising such substrates can be formulated according to known conventional methods. The pharmaceutical compositions can be administered to an individual in a suitable dosage. The administration can be oral or parenteral, e.g. intravenous, intraperitoneal, subcutaneous, intramuscular, local, intranasal, intrabronchial, oral or intradermal, or via a catheter into an artery. Preparations for a parenteral administration include sterile aqueous or non-aqueous solutions, suspensions and emulsions. Examples of non-aqueous solvents are propylene glycol, polyethylene glycol, vegetable oils such as e.g. olive oil, and organic ester compounds such as e.g. ethyl oleate which are suitable for injections. Aqueous substrates include water, hydroalcoholic solutions, emulsions, suspensions, salt solutions and buffered media. Parenteral substrates include sodium chloride solutions, Ringer's dextrose, dextrose and sodium chloride, lactated Ringer's solution and bonded oils. Intravenous substrates include e.g. liquid, nutritive and electrolyte supplements (such as e.g. those based on Ringer's dextrose). The pharmaceutical composition can also comprise preservatives and other additives, such as e.g. antimicrobial compounds, antioxidants, complex formers and inert gases. Furthermore, depending on the intended specific use, other active substances can be present such as e.g. interleukins, growth factors, differentiation factors, interferons, chemotactic proteins or an unspecific immunomodulator.
The type of dosage is determined by the physician in charge in accordance with the clinical factors. The person skilled in the art is aware of the fact that the type of dosage depends on different factors, such as e.g. the body height and weight, the body surface, the age, sex or general health of the patient, but also on the specific preparation to be administered, the duration and manner of administration, and on other drugs which may be administered at the same time. A typical dose can e.g. be in a range of between 0.001 and 1,000 μg, wherein doses below and above this exemplary range are also conceivable, in particular when keeping in mind the above-mentioned factors. In general, when administered regularly, the composition according to the present invention should be administered in doses in a range of between 1 μg and 10 mg units per day. In these preparations, the active substances will usually be present in a concentration of more than 10 μg/ml of a physiological buffer. However, they can also be present in solid form at a concentration of 0.1 to 99.5 wt.-% of the total mixture. Generally it has been shown to be advantageous to administer the active substance(s) in total amounts of about 0.001 to 100 mg/kg, preferably in total amounts of about 0.01 to 10 mg/kg body weight, over 24 hours, optionally as a continuous infusion or in the form of several individual doses to achieve the desired result. If the composition is administered intravenously, the dosage should be in the range of between 1 μg and 10 mg units per kilogram body weight per day. The pharmaceutical composition can be administered topically, locally or systemically.
The present invention also relates to methods for the treatment or diagnosis of neurodegenerative disorders or amyloid diseases comprising administering a pharmaceutical compositions according to the present invention or a diagnostic composition according to the present invention to a subject.
In a preferred embodiment of the method, the subject is a human being.
In a preferred embodiment of the use or the method, the neurodegenerative disorder is selected from a group consisting of Alzheimer's disease, Parkinson's syndrome and polyglutamine diseases.
Here, it is preferred that Parkinson's syndrome encompass idiopathic Parkinson's disease as well as atypical Parkinson's syndromes associated with protein aggregation; and that polyglutamine diseases encompass Huntington's chorea, spinocerebellar ataxias of types 1, 2, 3, 6, 7 and 17, dentatorubral pallidoluysian atrophy as well as spinobulbar muscular atrophy (Kennedy syndrome).
It is furthermore preferred that the amyloid disease be selected from the group consisting of: Hereditary and non-hereditary prion diseases (kuru, fatal familial insomnia, Gerstmann-Straussler-Scheinker syndrome, Creutzfeld-Jacob disease, new variant of Creutzfeld-Jacob disease), dementia with Lewy bodies, primary systemic amyloidosis, secondary systemic amyloidosis with deposits of serum amyloid A, senile systemic amyloidosis, familial amyloid polyneuropathy types I and III, familial nonneuropathic amyloidosis, familial British dementia, hereditary cerebral amyloid angiopathy, hemodialysis-associated amyloidosis, familial amyloidosis-Finnish type, diabetes mellitus type II, hereditary renal amyloidosis, injection amyloidosis with deposits of insulin, medullary carcinoma of the thyroid with deposits of calcitonin, atrial amyloidosis with deposits of ANF, inclusion body myositis.
As has already been explained in the description of the main embodiment, the active substances or chemical agents contained in the pharmaceutical or diagnostic compositions according to the present invention can be divided into 6 groups based on their chemical structure. In the following, these groups will be described in detail.
This group contains polycyclic compounds whose outstanding characteristic is the presence of at least tricyclic aromatic groups. The aromatic functional groups are either bonded to numerous hydroxy groups or contain oxo groups, or substitutions with oxygen or nitrogen atoms occur in the aromatic rings themselves.
In particular, this includes the derivatives of the following molecular scaffolds:
Molecular scaffold I-1:
R can be:
Preferred pharmaceutical or diagnostic compositions according to the present invention comprise an active substance with a structure according to formula I-1, wherein the active substance is selected from:
Other pharmaceutical or diagnostic compositions according to the present invention comprise active substances selected from the following derivatives:
Molecular scaffold I-2:
X can be:
R1 to R2 can be:
Preferred pharmaceutical or diagnostic compositions according to the present invention comprise an active substance with a structure according to formula I-2, wherein the active substance is
Molecular scaffold I-3:
X can be any heteroatom, specifically, N, O, P and S are possible atoms
R1 to R2 can be:
The following compound shall be mentioned as an example of this subgroup:
Molecular scaffold I-4:
X1 and X2 can be any heteroatom, however, in particular N, O, P and S
R1 to R8 can be:
Preferred pharmaceutical or diagnostic compositions according to the present invention comprise an active substance with a structure according to formula I-4, wherein the active substance is:
Preferred pharmaceutical or diagnostic compositions according to the present invention comprise an active substance with the above structure, wherein the active substance is selected from:
Other pharmaceutical or diagnostic compositions according to the present invention comprise active substances selected from the following derivatives:
Molecular scaffold I-5:
R1 to R6 can be:
Preferred pharmaceutical or diagnostic compositions according to the present invention comprise an active substance with a structure according to formula I-5 or formula I-7 described above, wherein the active substance is:
Other pharmaceutical or diagnostic compositions according to the present invention comprise active substances selected from the following derivatives:
Molecular scaffold I-6:
R1 to R4 can be:
An example of this group is
The chemical agents of group II comprise a 2-oxo-1,2-dihydro-pyridine-3-carbonitrile group (molecular scaffold II-1). Most substances are characterized by a special modification of this structure. This compound (2-amino-7-oxo-6,7-dihydro-thiazole[4,5-f]quinoline-8-carbonitrile) is referred to as molecular scaffold II-1 in Table 1. Table 1 lists all the structures of group II including their structure, chemical name, molecular weight and empirical formula.
Molecular scaffold II-1
The invention encompasses derivatives of the molecular scaffold II-1,
R1, R2, R3 and R4 can be:
As an example, in particular the compounds represented by the structural formulas below should be protected:
Molecular scaffold II-2
The invention encompasses derivatives of the molecular scaffold II-2,
wherein R1 and R2
Preferred pharmaceutical or diagnostic compositions according to the present invention comprise an active substance with a structure according to formula II-2, wherein the active substance is selected from:
Other pharmaceutical or diagnostic compositions according to the present invention comprise active substances selected from the following derivatives:
Compounds of group III are characterized by the presence of a nitrogen- or oxygen-containing heterocycle. Group III includes 6 molecular scaffolds (molecular scaffolds III-1 to III-6) (Table 3).
Molecular scaffold III-1:
X can represent: H, OH, NH2, Hal
R1 to R3 can be:
Molecular scaffold III-2:
R1 to R3 can be:
Examples of the substance group:
Molecular scaffold III-3:
R can be:
Examples of the substance group:
Molecular scaffold III-4:
R can be:
Examples of the substance group:
Molecular scaffold III-5:
X1 and X2 can represent:
R can be:
Examples of this substance group:
Molecular scaffold III-6:
R1 and R2 can represent:
Examples of this substance group:
The compounds of this group comprise acid amides which are bonded covalently to cyclic aromatic compounds. Group IV consists of a total of 6 molecular scaffolds (Table 4).
Molecular scaffold IV-1:
R can be:
Example of this substance group:
Molecular scaffold IV-2:
R can be:
Examples of this substance group:
Molecular scaffold IV-3:
R can be:
Example of this substance group:
Molecular scaffold IV-4:
R1 to R3 can be:
Examples of this substance group:
Since no unambiguous designation of this substance could be found, the structural formula is given to identify this substance:
Molecular scaffold IV-5:
R1 to R8 can be:
Examples include:
Molecular scaffold IV-6:
X1 and X2 can be:
R1 and R2 can be:
As examples, the following compounds should explicitly be protected:
Group V contains 4 catechins, which are ingredients of green tea. For this group, patent protection is only sought for the use of the substances and their derivatives in the diagnosis and treatment of Huntington's chorea and other diseases wherein a pathological deposit of polyglutamine-containing proteins is observed. All the structures of group V are listed in the annex, Table 5, including their structure, chemical name, molecular weight and empirical formula. They are the following structures and their derivatives:
(-)-Epigallocatechin gallate (EGCG)(Formula V-1)
(-)-Gallocatechin gallate (GCG) (Formula V-2)
(−)-Epigallocatechin (EGC) (Formula V-3)
(−)-Gallocatechin (GC) (Formula V-4)
The chemical agents of this group comprise benzothiazole compounds. Group VI encompasses two molecular scaffolds VI-1 and VI-2 (Table 6).
Molecular scaffold VI-1:
R1 to R5 can be:
Protection is sought explicitly for the following derivatives of molecular scaffold VI-1:
Molecular scaffold VI-2:
X1 can be:
X2 can be: O or S
R1 to R3 can be:
Example of derivatives of molecular scaffold VI-2:
The present invention also relates to pharmaceutical or diagnostic compositions comprising derivatives of one or more of the active substances mentioned above. Derivatives particularly include those that can for example be obtained by modifications such as the esterification of hydroxy groups with organic and inorganic acids, the introduction or replacement of substituents in aromatics or side chains, the derivatization of hydroxy groups to acetals or ketals, the N-acetylation to amides or phenyl carbamates, the introduction of isosteric or bioisosteric units, the synthesis of Mannich bases or imines, the introduction of branched side chains, the transformation of ketones or aldehydes into Schiff bases, oximes, acetals, ketals, enol esters, oxazolidines, thiazolidines, the replacement of simple side chains with branched side chains and vice versa, the conversion of alkyl substituents to cyclic analogues, or by combinations of these modifications.
The figures show:
The examples illustrate the invention.
For the in vitro experiments, the aggregation inhibiting effect of the compounds on mutant huntingtin was first examined with the help of the GST fusion protein GST-HDQ51. As in the tests described by Heiser et al. (2002), the protein was used for aggregation tests to which either only solvent or solvent and the chemical agent in question was added. Aliquots of these batches were examined by means of the membrane filter test and electron microscopy. By means of one of the two or both methods, an aggregation inhibiting effect of the listed compounds could be verified.
Analogously, the compounds were also examined in aggregation assays with the amyloid β-peptide Aβ1-42(E22Ω), which is a particularly rapidly aggregating variant of amyloid β, as well as with non-mutated (wild type) Aβ1-42. For this purpose, the peptide was incubated at a concentration of 15 μM in a phosphate buffer with a physiological pH value of 7.4 for 42 h at 37° C. and subsequently, aliquots were examined by means of the membrane filter method (Figure) or electron microscopy (Figures) as well. These tests showed that the compounds listed also effectively inhibit the aggregation of the amyloid β-peptide in vitro. Cell viability measurements were carried out in neuronally differentiated PC12 cells to which beta-amyloid and the substances to be tested were added extracellularly in order to examine whether the compounds are able to reduce toxicity caused by amyloid-beta. After 48 h the viability of the cells (approximately corresponds to the number of vital cells) was measured.
The compounds were then tested in several cell culture models of polyglutamine diseases, inter alia Huntington's chorea. For this purpose, COS1 cells were transiently transfected with the plasmid pTL1-CAG51 already described above (Sittler, A., Walter, S., Wedemeyer, N., Hasenbank, R., Scherzinger, E., Eickhoff, H., Bates, G. P., Lehrach, H. and Wanker, E. E. (1998) Mol Cell 2, 427-36) and cultivated for 44 h in the presence of solvents or the chemical agents. Subsequently, the amount of aggregate was determined with the help of the membrane filter test as described by Heiser et al. (2002). The compounds described showed an aggregation inhibiting influence in the cell culture model as well (Figures) without having a toxic effect at the concentrations used. The latter could be deduced from the total amount of protein in the cell lysate (
In addition, it was examined in this cell culture model of Huntington's chorea whether the substances tested substances can cause cell damage by initiating apoptotic processes. For this purpose, the activity of two caspases (caspases-3/-7) was determined fluorometrically after addition of a fluorogenic substrate. The measurements showed that the compounds have positive effects on the activation of caspases (Figures).
For some compounds, a positive effect could be observed in another cell culture model of Huntington's chorea and a cell culture model of spinocerebellar ataxia (type 3). A test system based on the aggregation of an N-terminal ataxin-3 deletion construct (aa 221-360) with 71 glutamines in COS-1 cells was developed to isolate substances inhibiting the ataxin-3 aggregation. The cells were transiently transfected with the ataxin-3 expression construct and incubated in plates with 96 perforations with the added substance at 37° C. in an incubator. After 40 h the cells were harvested and lysated. The lysates were denatured in the presence of 2% SDS and analyzed using the filtration method.
In order to detect the inhibiting effect of the substances on the aggregation of alpha-synuclein, the formation of amyloid fibrils was observed with the help of electron microscopy. For this purpose, the wild type protein or a mutant (A53T) was used.
Inhibition of the aggregation of wild type Aβ1-42 (quantification of SDS-insoluble aggregates by means of membrane filter method) by 2-(1H-imidazole-4-yl)-1H-perimidine, 1-ethyl-1H-perimidine, 2-pyridine-3-yl-1H-perimidine and 2-p-tolyl-1H-perimidine (see
Inhibition of the aggregation of wild type Aβ1-42 (quantification of SDS-insoluble aggregates by means of membrane filter method) by 1,2-dimethyl-1H-perimidine, 4-(1H-perimidine-2-yl)-benzonitrile, 1H,3H-perimidine-2-thione and 3-(1H-perimidine-2-yl)-phenylamine (see
Inhibition of toxicity of extracellular wild type Aβ1-42 by 3-(1H-perimidine-2-yl)-phenylamine in mammalian cells (neuronally differentiated PC12 cells): Identification by means of MTT test (quantification of SDS-insoluble aggregates by means of membrane filter method) (see
Inhibition of the aggregation of huntingtin (Exon-1) (quantification of SDS-insoluble aggregates by means of membrane filter method) by (1-methyl-1H-perimidine-2-yl)-methanol (see
Inhibition of the amyloid fibril formation of huntingtin (Exon-1) (electron microscopy) by 2-pyridine-4-yl-2,3-dihydro-1H-perimidine (see
Inhibition of the aggregation of ataxin-3 in mammalian cells (quantification of SDS-insoluble aggregates by means of membrane filter method) by 8-fluoro-1,2-dimethyl-4,5-dihydro-pyrrolo[3,2,1-ij]quinoline-6-one (see
Inhibition of the aggregation of huntingtin in mammalian cells (quantification of SDS-insoluble aggregates by means of membrane filter method) by 8-fluoro-1,2-dimethyl-4,5-dihydro-pyrrolo[3,2,1-ij]quinoline-6-one (see
Inhibition of the aggregation of wild type Aβ1-42 (quantification of SDS-insoluble aggregates by means of membrane filter method) by 2-furan-2-yl-2,3,4,9-tetrahydro-1H-indenol[2,3-c]pyridine-3-carboxylic acid methyl ester (see
Inhibition of the aggregation of huntingtin in mammalian cells (quantification of SDS-insoluble aggregates by means of membrane filter method) by 3H-phenoxazine, phenoxazin-3-one, 7-amino-1,9-dimethyl-phenoxazine-3-one, beta-amino-orcein, alpha-amino-orcein and alpha-hydroxy-orcein (see
Inhibition of the aggregation of wild type Aβ1-42 (quantification of SDS-insoluble aggregates by means of membrane filter method) by 1,9-dimethyl-phenoxazine-3-one (see
Inhibition of the aggregation of wild type Aβ1-42 (quantification of SDS-insoluble aggregates by means of membrane filter method) by 7-hydroxy-1,9-dimethyl-phenoxazine-3-one (see
Inhibition of the aggregation of wild type Aβ1-42 (quantification of SDS-insoluble aggregates by means of membrane filter method) by alpha-amino-orcein (see
Inhibition of the aggregation of wild type Aβ1-42 (quantification of SDS-insoluble aggregates by means of membrane filter method) by beta-hydroxy-orcein (see
The following—colored—substances bind directly to amyloid-beta fibrils (see
Inhibition of the toxicity of extracellular wild type Aβ1-42 by the substances in mammalian cells (neuronally differentiated PC12 cells: Identification by means of MTT test) (quantification of SDS-insoluble aggregates by means of membrane filter method) by alpha-amino-orcein (see
In this example, the compound 7-amino-8-(2,4-dihydroxy-6-methyl-phenyl)-1,9-dimethyl-phenoxazine-3-one (also referred to as # 6 in
For the in vitro experiments, the aggregation inhibiting effect of 7-amino-8-(2,4-dihydroxy-6-methyl-phenyl)-1,9-dimethyl-phenoxazine-3-one on mutant huntingtin was first examined with the help of the GST fusion protein GST-HDQ51. As in the tests described by Heiser et al. (2002), the protein was used for aggregation tests to which either only solvent or solvent and 7-amino-8-(2,4-dihydroxy-6-methyl-phenyl)-1,9-dimethyl-phenoxazine-3-one was added. Aliquots of these batches were examined by means of the membrane filter test (
Analogously, the compound was also examined in aggregation assays with the amyloid β-peptide Aβ1-42[E22Q] which is a particularly rapidly aggregating variant of amyloid β. For this purpose, the peptide was incubated at a concentration of 15 μM in a phosphate buffer with a physiological pH value of 7.4 for 42 h at 37° C. and subsequently, aliquots were examined by means of the membrane filter method (
7-Amino-8-(2,4-dihydroxy-6-methyl-phenyl)-1,9-dimethyl-phenoxazine-3-one was then tested in a cell culture model of Huntington's chorea. For this purpose, COS1 cells were transiently transfected with the plasmid pTL1-CAG51 already described above (Sittler, A., Walter, S., Wedemeyer, N., Hasenbank, R., Scherzinger, E., Eickhoff, H., Bates, G. P., Lehrach, H. and Wanker, E. E. (1998) Mol Cell 2, 427-36) and cultivated for 40-44 h in the presence of solvents or 7-amino-8-(2,4-dihydroxy-6-methyl-phenyl)-1,9-dimethyl-phenoxazine-3-one. Subsequently, the amount of aggregate was determined with the help of the membrane filter test as described by Heiser et al. (2002). 7-Amino-8-(2,4-dihydroxy-6-methyl-phenyl)-1,9-dimethyl-phenoxazine-3-one showed an aggregation inhibiting influence in the cell culture model as well (
In addition, it was examined in this cell culture model of Huntington's chorea whether 7-amino-8-(2,4-dihydroxy-6-methyl-phenyl)-1,9-dimethyl-phenoxazine-3-one can cause cell damage by initiating apoptotic processes. For this purpose, the activity of two caspases (caspases 3 and 7) was determined fluorometrically after addition of a fluorogenic substrate. The measurements showed that the cultivation in the presence of 7-amino-8-(2,4-dihydroxy-6-methyl-phenyl)-1,9-dimethyl-phenoxazine-3-one not only did not cause cell damage but, to the contrary, had an especially favorable effect on the cells since their caspase activity was reduced (
This observation is in line with the observation that in the presence of 7-amino-8-(2,4-dihydroxy-6-methyl-phenyl)-1,9-dimethyl-phenoxazine-3-one the total protein content was increased by almost 20% which can be interpreted as a sign for increased cell growth.
The experiments presented here using 7-amino-8-(2,4-dihydroxy-6-methyl-phenyl)-1,9-dimethyl-phenoxazine-3-one as an example were also carried out analogously with the other compounds. In the case of some compounds, a positive effect could be observed in another cell culture model of Huntington's chorea and in a cell culture model of spinocerebellar ataxia (type 3).
The experiments presented here using 7-amino-8-(2,4-dihydroxy-6-methyl-phenyl)-1,9-dimethyl-phenoxazine-3-one as an example were also carried out analogously with the other compounds (see examples above and below). In the case of some compounds, a positive effect could be observed in another cell culture model of Huntington's chorea and in a cell culture model of spinocerebellar ataxia (type 3).
Inhibition of the aggregation of huntingtin (Exon-1) (quantification of SDS-insoluble aggregates by means of membrane filter method) by dihydroxyanthraquinone (danthron) (see
Inhibition of the aggregation of huntingtin (Exon-1) (quantification of SDS-insoluble aggregates by means of membrane filter method) by chrysarobin (see
The compounds were additionally tested in a stably transfected PC12 cell line. This cell line was transfected with an ecdysone-inducible plasmid whose N-terminal codes for huntingtin-Exon-1 marked with GFP with 103 glutamines (Htt103Q-EGFP). The Htt103Q-EGFP expression was induced with muristerone and the cells were subsequently cultivated for 44 h in the presence of solvents or the chemical agents. Subsequently, the amount of aggregate was determined with the help of the membrane filter test as described by Heiser et al. (2002). Furthermore, the amount of aggregate was determined with the help of a fluorescence measurement (data not shown). The compounds described showed an aggregation inhibiting influence in the cell culture model as well (Figures) without having a toxic effect at the concentrations used. The latter could be deduced from the total amount of protein in the cell lysate (
Inhibition of the aggregation of huntingtin (Exon-1) in mammalian cells (quantification of SDS-insoluble aggregates by means of membrane filter method) by 2-amino-7-oxo-6,7-dihydro-thiazolo[4,5-f]quinoline-8-carbonitrile (see
Inhibition of the aggregation of ataxin-3 in mammalian cells (quantification of SDS-insoluble aggregates by means of membrane filter method) by thiophene-2-yl-acetic acid 4-(4-acetyl-piperazine-1-yl)-phenyl ester (see
Inhibition of the aggregation of huntingtin in mammalian cells (quantification of SDS-insoluble aggregates by means of membrane filter method) by thiophene-2-yl-acetic acid 4-(4-acetyl-piperazine-1-yl)-phenyl ester (see
Inhibition of the aggregation of huntingtin in mammalian cells (quantification of SDS-insoluble aggregates by means of membrane filter method) by 5-[4-(thiazole-2-ylcarbamoyl)-phenyl]-furan-2-carboxylic acid thiazole-2-ylamide (see
Inhibition of the aggregation of huntingtin in mammalian cells (quantification of SDS-insoluble aggregates by means of membrane filter method) by 4-methyl-2-[3-(3-phenyl-[1,2,4]thiadiazole-5-yl)-ureido]-pentanoic acid ethyl ester (see
Inhibition of the aggregation of huntingtin in mammalian cells (quantification of SDS-insoluble aggregates by means of membrane filter method) by 4-methyl-2-(3-phenyl-[1,2,4]thiadiazole-5-yl)-pentanoic acid ethyl ester (see
Inhibition of the aggregation of mutated huntingtin (quantification of SDS-insoluble aggregates by means of membrane filter method) by EGCG (Epigallocatechin gallate), GCG (Gallocatechin gallate), GC (Gallocatechin) and EGC (Epigallocatechin) (see
Inhibition of the aggregation of alpha-synuclein (representation of the amyloid fibrils by means of electron microscopy) by EGCG (Epigallocatechin gallate), GCG (Gallocatechin gallate), GC (Gallocatechin) and EGC (Epigallocatechin) (see
Number | Date | Country | Kind |
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10 2004 007 384.8 | Feb 2004 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP05/01389 | 2/11/2005 | WO | 00 | 3/10/2008 |