Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K49/00—Preparations for testing in vivo
  • A61K49/06—Nuclear magnetic resonance [NMR] contrast preparations; Magnetic resonance imaging [MRI] contrast preparations
  • A61K49/08—Nuclear magnetic resonance [NMR] contrast preparations; Magnetic resonance imaging [MRI] contrast preparations characterised by the carrier
  • A61K49/10—Organic compounds
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K49/00—Preparations for testing in vivo
  • A61K49/06—Nuclear magnetic resonance [NMR] contrast preparations; Magnetic resonance imaging [MRI] contrast preparations
  • A61K49/18—Nuclear magnetic resonance [NMR] contrast preparations; Magnetic resonance imaging [MRI] contrast preparations characterised by a special physical form, e.g. emulsions, microcapsules, liposomes
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
  • A61P35/00—Antineoplastic agents
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
  • G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
  • G01N33/50—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing
  • G01N33/5005—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing involving human or animal cells
  • G01N33/5008—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing involving human or animal cells for testing or evaluating the effect of chemical or biological compounds, e.g. drugs, cosmetics
  • G01N33/502—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing involving human or animal cells for testing or evaluating the effect of chemical or biological compounds, e.g. drugs, cosmetics for testing non-proliferative effects
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
  • G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
  • G01N33/50—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing
  • G01N33/53—Immunoassay; Biospecific binding assay; Materials therefor
  • G01N33/575—Immunoassay; Biospecific binding assay; Materials therefor for cancer
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
  • G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
  • G01N33/50—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing
  • G01N33/68—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing involving proteins, peptides or amino acids
  • G01N33/6803—General methods of protein analysis not limited to specific proteins or families of proteins
  • G01N33/6848—Methods of protein analysis involving mass spectrometry
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N2458/00—Labels used in chemical analysis of biological material
  • G01N2458/15—Non-radioactive isotope labels, e.g. for detection by mass spectrometry
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N2510/00—Detection of programmed cell death, i.e. apoptosis

Definitions

• Imaging medium comprising lactate and hvperpolarised 13 C-pyruvate
• the invention relates to an imaging medium containing lactate and hyperpolarised 13 C-pyruvate, a method to produce said imaging medium, use of said imaging medium and methods of 13 C-MR imaging and/or 13 C-MR spectroscopy wherein said imaging medium is used.
• Magnetic resonance (MR) imaging is a technique that has become particularly attractive to physicians as images of a patients body or parts thereof can be obtained in a non-invasive way and without exposing the patient and the medical personnel to potentially harmful radiation such as X-rays. Because of its high quality images and good spatial and temporal resolution, MRI is a favourable imaging technique for imaging soft tissue and organs.
• MRI may be carried out with or without MR contrast agents.
• contrast- enhanced MRI usually enables the detection of much smaller tissue changes which makes it a powerful tool for the detection of early stage tissue changes like for instance small tumours or metastases.
• T 1 agents for use as MR imaging agents are disclosed in WO-A-99/35508, including non-endogenous and endogenous compounds like acetate, pyruvate, oxalate or gluconate, sugars like glucose or fructose, urea, amides, amino acids like glutamate, glycine, cysteine or aspartate, nucleotides, vitamins like ascorbic acid, penicillin derivates and sulphonamides. It is further stated that intermediates in metabolic cycles such as the citric acid cycle are preferred imaging agents for MR imaging of metabolic activity.
• Pyruvate is an endogenous compound which is very well tolerated by the human body, even in high concentrations.
• pyruvate plays an important metabolic role in the human body. Pyruvate is converted into different compounds: its transamination results in alanine, via oxidative decarboxylation, pyruvate is converted into acetyl-CoA and carbon dioxide (which is further converted to bicarbonate), the reduction of pyruvate results in lactate and its carboxylation in oxaloacetate.
• hyperpolarised 13 C-pyruvate to its metabolites hyperpolarised 13 C-lactate, hyperpolarised 13 C-bicarbonate (in the case of 13 C 1 - pyruvate, I3 C ls2 -pyruvate or 13 C 1;2j3 -pyruvate only) and hyperpolarised 13 C-alanine can be used for in vivo MR study of metabolic processes in the human body.
• 13 C 1 - pyruvate has a T 1 relaxation in human full blood at 37° C of about 42 s, however, the conversion of hyperpolarised C-pyruvate to hyperpolarised C-lactate, hyperpolarised 13 C-bicarbonate and hyperpolarised 13 C-alanine has been found to be fast enough to allow signal detection from the 13 C-pyruvate parent compound and its metabolites.
• the amount of alanine, bicarbonate and lactate is dependent on the metabolic status of the tissue under investigation.
• the MR signal amplitudes arising from the different pyruvate metabolites vary depending on the tissue type.
• the unique metabolic peak pattern formed by alanine, lactate, bicarbonate and pyruvate can be used as fingerprint for the metabolic state of the tissue under examination.
• an MR imaging agent containing non-hyperpolarised lactate and hyperpolarised I3 C-pyruvate has superior properties compared to hyperpolarised 13 C-pyruvate alone.
• the use of such an imaging agent leads to an increased amount of observable 13 C-lactate and thus an increased MR signal from 13 C-lactate.
• the signal from 13 C-lactate is the signal one would monitor for MR tumour imaging where tumour tissue is indicated by a high 13 C-lactate signal as described in WO-A-2006/011810. With an increased signal from 13 C-lactate, it may be possible to detect smaller tumours or tumour tissue at a very early stage.
• the signal from 13 C-lactate is also the signal one would monitor for MR cardiac imaging where myocardial tissue at risk, i.e. ischemic myocardial tissue, is identified by the lowest 13 C-bicarbonate signal and/or the highest 13 C-lactate signal as described in WO-A-2006/054903. Further, the signal from 13 C-lactate is the signal one would monitor for MR imaging of cell death, where dying tissue is indicated by a low or absent 13 C-lactate signal.
• the invention provides a method of 13 C-MR imaging or 13 C- MR spectroscopy using an imaging medium comprising lactate and hyperpolarised 13 C-pyruvate.
• hypopolarised and “polarised” are used interchangeably hereinafter and denote a nuclear polarisation level in excess of 0.1%, more preferred in excess of 1% and most preferred in excess of 10%.
• the level of polarisation may for instance be determined by solid state 13 C-NMR measurements in solid hyperpolarised C-pyruvate, e.g. solid hyperpolarised C- pyruvate obtained by dynamic nuclear polarisation (DNP) of 13 C-pyruvate.
• the solid state 13 C-NMR measurement preferably consists of a simple pulse-acquire NMR sequence using a low flip angle.
• the signal intensity of the hyperpolarised 13 C- pyruvate in the NMR spectrum is compared with signal intensity of 13 C-pyruvate in a PN0681-PCT/FI/18.08.2007 NMR spectrum acquired before the polarisation process.
• the level of polarisation is then calculated from the ratio of the signal intensities of before and after polarisation.
• the level of polarisation for dissolved hyperpolarised 13 C-pyruvate may be determined by liquid state NMR measurements. Again the signal intensity of the dissolved hyperpolarised 13 C-pyruvate is compared with the signal intensity of the dissolved 13 C-pyruvate before polarisation. The level of polarisation is then calculated from the ratio of the signal intensities of 13 C-pyruvate before and after polarisation.
• imaging medium denotes a liquid composition comprising hyperpolarised 13 C-pyruvate as the MR active agent, i.e. imaging agent and lactate which is non-hyperpolarised.
• the imaging medium according to the invention may be used as imaging medium in MR imaging or as MR spectroscopy agent in MR spectroscopy.
• the imaging medium used in the method of the invention may be used as an imaging medium for in vivo 3 C-MR imaging or spectroscopy, i.e. in living human or non- human animal beings. Further, the imaging medium used in the method of the invention may be used as imaging medium for in vitro 13 C-MR imaging or spectroscopy, e.g. in cell cultures, samples derived from a human or non human body like for instance urine, saliva or blood or in ex vivo tissue, for instance ex vivo tissue obtained from a biopsy.
• 13 C-pyruvate used in the method of the invention may be isotopically enriched at the Cl -position (in the following denoted 13 C 1 - pyruvate), at the C2-position (in the following denoted 13 C 2 -pyruvate), at the C3- position (in the following denoted 13 C 3 -pyruvate), at the Cl- and the C2-position (in the following denoted 13 Ci,2-pyruvate), at the Cl- and the C3- ⁇ osition (in the following denoted 13 C l53 -pyruvate), at the C2- and the C3 -position (in the following denoted 13 C 2 , 3 -pyruvate) or at the Cl-, C2- and C3-position (in the following PN0681-PCT/FI/18.08.2007 denoted 13 Ci, 2 , 3 -pyruvate). Isotopic enrichment at the Cl-position is preferred since
• ⁇ Crpyruvate has a higher Ti relaxation in human full blood at 37° C (about 42 s) than I3 C-pyruvate which is isotopically enriched at other C-positions.
• Hyperpolarisation of NMR active 13 C-nuclei may be achieved by different methods which are for instance described in described in WO-A-98/30918, WO-A-99/24080 and WO-A-99/35508, which are incorporated herein by reference and hyperpolarisation methods are polarisation transfer from a noble gas, "brute force", spin refrigeration, the parahydrogen method and dynamic nuclear polarisation (DNP).
• hyperpolarised 13 C-pyurvate it is preferred to either polarise 13 C-pyruvate directly or to polarise 13 C-pyruvic acid and convert the polarised I3 C-pyruvic acid to polarised 13 C-pyruvate, e.g. by neutralisation with a base
• hyperpolarised C-pyruvate is the polarisation transfer from a hyperpolarised noble gas which is described in WO-A-98/30918.
• Noble gases having non-zero nuclear spin can be hyperpolarised by the use of circularly polarised light.
• a hyperpolarised noble gas preferably He or Xe, or a
• the hyperpolarised gas may be in the gas phase, it may be dissolved in a liquid/solvent, or the hyperpolarised gas itself may serve as a solvent. Alternatively, the gas may be condensed onto a cooled solid surface and used in this form, or allowed to sublime. Intimate mixing of the hyperpolarised gas with 13 C-pyruvate or I3 C-pyruvic acid is preferred. Hence, if 13 C-pyruvic acid is polarised, which is a liquid at room temperature, the hyperpolarised gas is preferably dissolved in a liquid/solvent or serves as a solvent. If 13 C pyruvate is polarised, the hyperpolarised gas is preferably dissolved in a liquid/solvent, which also dissolves pyruvate.
• hyperpolarisation is imparted to 13 C-nuclei by thermodynamic equilibration at a very low temperature and high field.
• Hyperpolarisation compared to the operating field and temperature of the NMR spectrometer is effected by use of a very high field and very low temperature (brute force).
• the magnetic field strength used should be as high as PN0681-PCT/FI/18.08.2007 possible, suitably higher than 1 T, preferably higher than 5 T, more preferably 15 T or more and especially preferably 20 T or more.
• the temperature should be very low, e.g. 4.2 K or less, preferably 1.5 K or less, more preferably 1.0 K or less, especially preferably 100 mK or less.
• Another suitable way for obtaining hyperpolarised 13 C-pyruvate is the spin refrigeration method.
• This method covers spin polarisation of a solid compound or system by spin refrigeration polarisation.
• the system is doped with or intimately mixed with suitable crystalline paramagnetic materials such as Ni 2+ , lanthanide or actinide ions with a symmetry axis of order three or more.
• suitable crystalline paramagnetic materials such as Ni 2+ , lanthanide or actinide ions with a symmetry axis of order three or more.
• the instrumentation is simpler than required for DNP with no need for a uniform magnetic field since no resonance excitation field is applied.
• the process is carried out by physically rotating the sample around an axis perpendicular to the direction of the magnetic field.
• the pre-requisite for this method is that the paramagnetic species has a highly anisotropic g-factor.
• the electron paramagnetic resonance will be brought in contact with the nuclear spins, leading to a decrease in the
• DNP dynamic nuclear polarisation
• polarisation of MR active nuclei in a compound to be polarized is affected by a polarisation agent or so-called DNP agent, a compound comprising unpaired electrons.
• DNP agent a compound comprising unpaired electrons.
• energy normally in the form of microwave radiation, is provided, which will initially excite the DNP agent.
• the unpaired electron of the DNP agent is provided, which will initially excite the DNP agent.
• the unpaired electron of the DNP agent Upon decay to the ground state, there is a transfer of polarisation from the unpaired electron of the DNP agent to the NMR active nuclei of the compound to be polarised, e.g. to the C nuclei in C-pyruvate.
• a moderate or high magnetic field and a very low temperature are used in the DNP process, e.g. by carrying out the DNP process in liquid helium and a magnetic field of about 1 T or above.
• a moderate magnetic field and any temperature at which sufficient polarisation enhancement is achieved may be employed.
• the DNP technique is for example further described in WO-A-98/58272 and in WO-A- 01/96895, both of which are included by reference herein.
• a mixture of the compound to be polarised and a DNP agent is prepared ("a sample") which is then frozen and inserted into a DNP polariser for polarisation.
• a sample a mixture of the compound to be polarised and a DNP agent
• the frozen solid hyperpolarized sample is rapidly transferred into the liquid state either by melting it or by dissolving it in a suitable dissolution medium. Dissolution is preferred and the dissolution process of a frozen hyperpolarized sample and suitable devices therefore are described in detail in WO-A-02/37132.
• the melting process and suitable devices for the melting are for instance described in WO- A-02/36005.
• Isotopically enriched 13 C-pyruvate is commercially available, e.g. as sodium 13 C- pyruvate. Alternatively, it may be synthesized as described by S. Anker, J. Biol. Chem 176, 1948, 133-1335.
• C-pyruvic acid may be obtained by protonating commercially available sodium 13 C-pyruvate, e.g. by the method described in US patent 6,232,497 or by the method described in WO-A-2006/038811.
• 13 C-pyruvic acid may be directly used for DNP since it forms a glass when frozen.
• the frozen hyperpolarised 13 C-pyruvic acid needs to be dissolved and neutralised, i.e. converted to 13 C-pyruvate.
• a strong base is needed.
• 13 C-pyruvic acid is a strong acid, a DNP agent needs to be chosen which is stable in this strong acid.
• C-pyruvate i.e. a salt of 13 C-pyruvic acid
• Preferred salts are those I3 C-pyruvates which comprise an inorganic cation from the group consisting Of NH 4 + , K + , Rb + , Cs + , Ca 2+ , Sr 2+ and Ba 2+ , preferably NH 4 + , K + , Rb + or Cs + , more preferably K + , Rb + , Cs + and most preferably Cs + , as in detail described in PCT7NO07/00109 and incorporated by reference herein.
• the synthesis of these preferred 13 C-pyruvates is disclosed in PCT/NO07/00109 as well.
• the hyperpolarized 13 C-pyruvate is used in an imaging medium for in vivo MR imaging and/or spectroscopy it is preferred to exchange the inorganic cation from the group consisting OfNH 4 + , K + , Rb + , Cs + , Ca 2+ , Sr 2+ and Ba 2+ by a physiologically very well tolerable cation like Na + or meglumine. This may be done by methods known in the art like the use of a cation exchange column.
• Further preferred salts are 13 C-pyruvates of an organic amine or amino compound, preferably TRIS- ⁇ Ci-pyruvate or meglumine- ⁇ d-pyruvate, as in detail described in WO-A-2007/069909 and incorporated by reference herein.
• the synthesis of these preferred 13 C-pyruvates is disclosed in WO-A-2007/069909 as well.
• the sample to be polarised comprising 13 C-pyruvic acid or 13 C-pyruvate and a DNP agent may further comprise a paramagnetic metal ion.
• the presence of paramagnetic metal ions in composition to be polarised by DNP has found to result in increased polarisation levels in the l3 C-pyruvic acid/ 13 C-pyruvate as described in detail in WO-A-2007/064226 which is incorporated herein by reference.
• the imaging medium according to the method of the invention may be used as imaging medium for in vivo MR imaging and/or spectroscopy, i.e. MR imaging and/or spectroscopy carried out on living human or non-human animal beings.
• Such an imaging medium preferably comprises in addition to the MR active agent 13 C-pyruvate an aqueous carrier, preferably a physiologically tolerable and pharmaceutically accepted aqueous carrier like water, a buffer solution or saline.
• Such an imaging medium may further comprise conventional pharmaceutical or veterinary carriers or excipients, e.g. formulation aids such as are conventional for diagnostic compositions in human or veterinary medicine.
• the imaging medium according to the method of the invention may be used as imaging medium for in vitro MR imaging and/or spectroscopy, e.g. for detecting cell death in cell cultures or ex vivo tissues.
• an imaging agent preferably comprises in addition to the MR active agent 13 C-pyruvate a solvent which is compatible with and used for in vitro cell or tissue assays, for instance DMSO or methanol or solvent mixtures comprising an aqueous carrier and a non aqueous solvent, for instance mixtures of DMSO and water or a buffer solution or methanol and water or a buffer solution.
• a solvent which is compatible with and used for in vitro cell or tissue assays for instance DMSO or methanol or solvent mixtures comprising an aqueous carrier and a non aqueous solvent, for instance mixtures of DMSO and water or a buffer solution or methanol and water or a buffer solution.
• pharmaceutically acceptable carriers, excipients and formulation aids may be present in such an imaging medium
• the imaging medium used in the method of the invention contains lactate and hyperpolarised 13 C-pyruvate.
• the lactate is non-hyperpolarised. Lactate is suitably added to the hyperpolarised 13 C-pyruvate after the polarisation process.
• lactate may be dissolved in said liquid composition or a solution of lactate in a suitable solvent, preferably an PN0681-PCT/FI/18.08.2007 aqueous carrier may be added to the liquid composition.
• lactate may be dissolved in the dissolution medium which is used to dissolve the solid composition.
• 13 C-pyruvate polarised by the DNP method may be dissolved in an aqueous carrier like water or a buffer solution containing lactate.
• lactate it is preferred to add lactate to the final liquid composition, i.e. to the liquid composition after dissolution/melting or to the liquid composition after removal of the DNP agent and/or an optional paramagnetic metal ion.
• the lactate may be added as a solid to the liquid composition or preferably dissolved in a suitable solvent, e.g.
• an aqueous carrier like water or a buffer solution.
• aqueous carrier like water or a buffer solution.
• stirring, vortexing or sonication may be used.
• methods are preferred which are quick and do not require a mixing device or help coming into contact with the liquid composition. Methods like vortexing or sonication are thus preferred.
• lactate in added in the form of lactic acid or a salt of lactic acid preferably lithium lactate or sodium lactate, most preferably sodium lactate.
• concentration of hyperpolarised 13 C-pyruvate and lactate in the imaging medium used in the method of the invention is about equal or equal or lactate is present at a lower or higher concentration than 13 C-pyruvate. If for instance the imaging agent contains x M 13 C-pyruvate, it contains x M or about x M or less lactate but preferably not less than a tenth of x M lactate or more lactate but preferably not more than three times x M lactate.
• the concentration of lactate in the imaging medium used in the method of the invention is about equal or equal to the concentration of hyperpolarised 13 C-pyruvate.
• the term "about equal concentration” denotes a lactate concentration which is +/- 30% of the concentration of 13 C- pyruvate, preferably +/- 20%, more preferably +/- 10%.
• the imaging medium comprising lactate and hyperpolarised 13 C-pyruvate is provided as a composition that is suitable for administration to a living human or non-human animal body.
• the imaging medium preferably comprises an aqueous carrier like a buffer or a mixture of buffers as PN0681 -PCT/FI/18.08.2007 described above.
• the imaging medium may further comprise conventional pharmaceutically acceptable carriers, excipients and formulation aids.
• the imaging medium may for example include stabilizers, osmolality adjusting agents, solubilising agents and the like.
• the imaging medium used in the method of the invention is used for in vivo MR imaging or spectroscopy, e.g. in a living human or non-human animal body
• said imaging medium is preferably administered to said body parenterally, preferably intravenously.
• the body under examination is positioned in an MR magnet.
• Dedicated 13 C-MR RF-coils are positioned to cover the area of interest. Dosage and concentration of the imaging medium will depend upon a range of factors such as toxicity and the administration route.
• the imaging medium is administered in a concentration of up to 1 mmol 13 C-pyruvate per kg bodyweight, preferably 0.01 to 0.5 mmol/kg, and more preferably 0.1 to 0.3 mmol/kg.
• the administration rate is preferably less than 10 ml/s, more preferably less than 6 ml/min and most preferable of from 5 ml/s to 0.1 ml/s.
• an MR imaging sequence is applied that encodes the volume of interest in a combined frequency and spatial selective way. This will result in metabolic images of 13 C-pyruvate and I3 C-lactate. The exact time of applying an MR sequence is highly dependent on the volume of interest.
• the imaging medium comprising lactate and hyperpolarised 13 C-pyruvate is provided as a composition that is suitable for being added to, for instance, cell cultures, samples derived from a human or non human body or ex vivo tissues like biopsy tissues.
• pharmaceutically acceptable carriers, excipients and formulation aids may be present in the imaging medium but are not required to be present for such a purpose, and the imaging medium thus preferably comprises an aqueous carrier like a buffer or a mixture of buffers as described above and/or one or more non aqueous solvents compatible with cell cultures or tissue like DMSO or methanol.
• PN0681 -PCT/FI/18.08.2007 tissue like biopsy tissues is preferably 10 mM to 100 mM in 13 C-pyruvate, more preferably 20 mM to 90 mM and most preferably 40 to 80 mM in 13 C-pyruvate.
• the invention provides an imaging medium comprising lactate and hyperpolarised 13 C-pyruvate.
• the imaging medium according to the invention contains about equal or equal concentrations of lactate and hyperpolarised 13 C- pyruvate or contains lactate in a lower or higher concentration than 13 C-pyruvate. If for instance the imaging agent contains x M 13 C-pyruvate, it contains x M or about x M or less lactate but preferably not less than a tenth of x M lactate or more lactate but preferably not more than three times x M lactate. In a preferred embodiment, the concentration of lactate in the imaging medium according to the invention is about equal or equal to the concentration of hyperpolarised 13 C-pyruvate.
• the term "about equal concentration” denotes a lactate concentration which is +/- 30% of the concentration of 3 C-pyruvate, preferably +/- 20%, more preferably +/- 10%.
• the lactate is selected from the group consisting of lactic acid, lithium lactate or sodium lactate.
• the imaging medium is preferably used in 13 C-MR imaging or 13 C-MR spectroscopy.
• the imaging medium according to the invention is used as in vivo imaging medium, i.e. administered to a living human or non-human animal being, said imaging medium preferably further an aqueous carrier like a buffer or a mixture of buffers as described above.
• the imaging medium may further comprise conventional pharmaceutically acceptable carriers, excipients and formulation aids.
• the imaging medium may for example include stabilizers, osmolality adjusting agents, solubilising agents and the like.
• the imaging medium according to the invention may further comprise pharmaceutically acceptable carriers, excipients and formulation aids as mentioned in the previous PN0681-PCT/FI/18.08.2007 paragraph. However, it is apparent for the skilled person that such pharmaceutically acceptable carriers, excipients and formulation aids are not required to be present for such a purpose.
• the imaging medium thus preferably further comprises an aqueous carrier like a buffer or a mixture of buffers as described above and/or one or more non aqueous solvents compatible with cell cultures or tissue like DMSO or methanol.
• Yet another aspect of the invention is a method for producing an imaging medium comprising lactate and hyperpolarised 13 C-pyruvate, wherein the hyperpolarised 13 C- pyruvate is obtained by dynamic nuclear polarisation of 13 C-pyruvic acid or 13 C- pyruvate and lactate is added to a solution of said hyperpolarised 13 C-pyruvate.
• a further aspect of the invention is the use of an imaging medium according to the invention for in vivo study of metabolic processes in the human or non human animal body using C-MR imaging and/or C-MR spectroscopy.
• a further aspect of the invention is the use of an imaging medium according to the invention for in vitro study of metabolic processes in cell cultures, samples derived from a human or non human body or ex vivo tissue using 13 C-MR imaging and/or 13 C-MR spectroscopy.
• Yet another aspect of the invention is the use of an imaging medium according to the invention for in vivo identification of tumour tissue in the human or non human animal body using C-MR imaging and/or C-MR spectroscopy.
• Yet another aspect of the invention is the use of an imaging medium according to the invention for in vitro identification of tumour cells in a cell culture, in samples derived from a human or non human body or in ex vivo tissue using 13 C-MR imaging and/or 13 C-MR spectroscopy.
• Yet another aspect of the invention is the use of an imaging medium according to the invention for in vivo assessment of the viability of myocardial tissue in the human or non human animal body using 13 C-MR imaging and/or 13 C-MR spectroscopy.
• Yet another aspect of the invention is the use of an imaging medium according to the invention for in vivo detection of cell death in the human or non human animal body using 13 C-MR imaging and/or 13 C-MR spectroscopy.
• the integral of the peak at its resonance frequency is directly related to the amount of 13 C-pyruvate and 13 C-lactate, respectively.
• the amount of 13 C-pyruvate and 13 C-lactate is estimated using time domain fitting routines as described for instance in L. Vanhamme et al., J Magn Reson 129, 35-43 (1997), images can be generated for 13 C-pyruvate and 13C- lactate in which a colour coding or grey coding is representative for the amount of 13 C-pyruvate and 13 C-lactate measured.
• the pH was adjusted to pH > 13 using 40 ml of 1 M NaOH (aq) and the mixture was stirred at ambient temperature for 15 hours to hydrolyse the formed methyl esters.
• the mixture was then acidified using 50 ml 2 M HCl (aq) to a pH of about 2 and 3 times extracted the ethyl acetate (500 ml and 2 x 200 ml).
• the combined organic phase was dried over Na 2 SO 4 and then evaporated to dryness.
• the crude product (24 g) was purified by preparative HPLC using acetonitrile/water as eluents. The collected fractions were evaporated to remove acetonitrile.

Landscapes

• Health & Medical Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Immunology (AREA)
• Molecular Biology (AREA)
• Biomedical Technology (AREA)
• Hematology (AREA)
• Urology & Nephrology (AREA)
• General Health & Medical Sciences (AREA)
• Physics & Mathematics (AREA)
• Medicinal Chemistry (AREA)
• Biotechnology (AREA)
• Food Science & Technology (AREA)
• Analytical Chemistry (AREA)
• Microbiology (AREA)
• Biochemistry (AREA)
• Bioinformatics & Cheminformatics (AREA)
• General Physics & Mathematics (AREA)
• Pathology (AREA)
• Cell Biology (AREA)
• Animal Behavior & Ethology (AREA)
• Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• Bioinformatics & Computational Biology (AREA)
• Epidemiology (AREA)
• Radiology & Medical Imaging (AREA)
• Toxicology (AREA)
• Proteomics, Peptides & Aminoacids (AREA)
• Tropical Medicine & Parasitology (AREA)
• Biophysics (AREA)
• Spectroscopy & Molecular Physics (AREA)
• Pharmacology & Pharmacy (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Medicines Containing Antibodies Or Antigens For Use As Internal Diagnostic Agents (AREA)
• Magnetic Resonance Imaging Apparatus (AREA)

Priority Applications (3)

Applications Claiming Priority (2)

Publications (2)

Family

ID=38719770

Family Applications (1)

Country Status (6)

Cited By (7)

Families Citing this family (6)

Family Cites Families (6)

• 2007
  • 2007-08-17 EP EP07808606A patent/EP2051739A2/en not_active Withdrawn
  • 2007-08-17 WO PCT/NO2007/000287 patent/WO2008020765A2/en not_active Ceased
  • 2007-08-17 US US12/376,478 patent/US20100178249A1/en not_active Abandoned
  • 2007-08-17 CN CNA2007800305934A patent/CN101505802A/zh active Pending
  • 2007-08-17 KR KR1020097003270A patent/KR20090052859A/ko not_active Withdrawn
  • 2007-08-17 JP JP2009524574A patent/JP2010501483A/ja not_active Withdrawn

Also Published As

Similar Documents

Legal Events