CLEFMA, 4-(3,5-bis(2-chlorobenzylidene)-4-oxo-piperidine-1-yl)-4-oxo-2-butenoic acid, is a new chemical entity with anti-cancer and anti-inflammatory activities. Here, we report its stability in solution against stres...CLEFMA, 4-(3,5-bis(2-chlorobenzylidene)-4-oxo-piperidine-1-yl)-4-oxo-2-butenoic acid, is a new chemical entity with anti-cancer and anti-inflammatory activities. Here, we report its stability in solution against stress conditions of exposure to acid/base, light, oxidant, high temperature, and plasma. The identity of the degradation products was ascertained by mass and proton nuclear magnetic resonance spectroscopy. To facilitate this study, we developed and validated a reverse phase high performance liquid chromatography method for detection of CLEFMA and its degradation. The method was linear over a range of 1–100 μg/m L; the accuracy and precision were within acceptable limits; it was stability-indicating as it successfully separated cis-/trans-isomers of CLEFMA as well as its degradation product. The major degradation product was produced from amide hydrolysis at maleic acid functionality caused by an acidic buffer, oxidant(3% hydrogen peroxide),or temperature stress(40–60 °C). The log k-p H profile showed that CLEFMA was most stable at neutral p H. In accelerated stability study we found that the shelf-life(T_(90%)) of CLEFMA at 25 °C and 4 °C was 45 days and220 days, respectively. Upon exposure to UV-light(365 nm), the normally prevalent trans-CLEFMA attained cis-configuration. This isomerization also involved the maleic acid moiety. CLEFMA was stable in plasma from which it could be efficiently extracted by an acetonitrile precipitation method. These results indicate that CLEFMA is sensitive to hydrolytic cleavage at its maleic acid moiety, and it is recommended that its samples should be stored under refrigerated and light-free conditions, and under inert environment.展开更多
Background:Drug-induced cardiomyopathy is a significant medical problem.Clinical diagnosis of myocardial injury is based on initial electrocardiogram,levels of circulating biomarkers,and perfusion imaging with single ...Background:Drug-induced cardiomyopathy is a significant medical problem.Clinical diagnosis of myocardial injury is based on initial electrocardiogram,levels of circulating biomarkers,and perfusion imaging with single photon emission computed tomography(SPECT).Positron emission tomography(PET)is an alternative imaging modality that provides better resolution and sensitivity than SPECT,improves diagnostic accuracy,and allows therapeutic monitoring.The objective of this study was to assess the detection of drug-induced cardiomyopathy by PET using 2-deoxy-2-[^18F]fluoro-D-glucose(FDG)and compare it with the conventional SPECT technique with[^99m Tc]-Sestamibi(MIBI).Methods:Cardiomyopathy was induced in Sprague Dawley rats using high-dose isoproterenol.Nuclear[^18F]FDG/PET and[^99m Tc]MIBI/SPECT were performed before and after isoproterenol administration.[^18F]FDG(0.1 mCi,200-400μL)and[^99m Tc]MIBI(2 mCi,200-600μL)were administered via the tail vein and imaging was performed 1 hour postinjection.Isoproterenol-induced injury was confirmed by the plasma level of cardiac troponin and triphenyltetrazolium chloride(TTC)staining.Results:Isoproterenol administration resulted in an increase in circulating cardiac troponin I and showed histologic damage in the myocardium.Visually,preisoproterenol and postisoproterenol images showed alterations in cardiac accumulation of[^18F]FDG,but not of[^99m Tc]MIBI.Image analysis revealed that myocardial uptake of[^18F]FDG reduced by 60%after isoproterenol treatment,whereas that of[^99m Tc]MIBI decreased by 45%.Conclusion:We conclude that[^18F]FDG is a more sensitive radiotracer than[^99m Tc]MIBI for imaging of drug-induced cardiomyopathy.We theorize that isoproterenolinduced cardiomyopathy impacts cellular metabolism more than perfusion,which results in more substantial changes in[^18F]FDG uptake than in[^99m Tc]MIBI accumulation in cardiac tissue.展开更多
基金partially funded by a grant from National Heart, Lung & Blood Institute [R01HL104286]
文摘CLEFMA, 4-(3,5-bis(2-chlorobenzylidene)-4-oxo-piperidine-1-yl)-4-oxo-2-butenoic acid, is a new chemical entity with anti-cancer and anti-inflammatory activities. Here, we report its stability in solution against stress conditions of exposure to acid/base, light, oxidant, high temperature, and plasma. The identity of the degradation products was ascertained by mass and proton nuclear magnetic resonance spectroscopy. To facilitate this study, we developed and validated a reverse phase high performance liquid chromatography method for detection of CLEFMA and its degradation. The method was linear over a range of 1–100 μg/m L; the accuracy and precision were within acceptable limits; it was stability-indicating as it successfully separated cis-/trans-isomers of CLEFMA as well as its degradation product. The major degradation product was produced from amide hydrolysis at maleic acid functionality caused by an acidic buffer, oxidant(3% hydrogen peroxide),or temperature stress(40–60 °C). The log k-p H profile showed that CLEFMA was most stable at neutral p H. In accelerated stability study we found that the shelf-life(T_(90%)) of CLEFMA at 25 °C and 4 °C was 45 days and220 days, respectively. Upon exposure to UV-light(365 nm), the normally prevalent trans-CLEFMA attained cis-configuration. This isomerization also involved the maleic acid moiety. CLEFMA was stable in plasma from which it could be efficiently extracted by an acetonitrile precipitation method. These results indicate that CLEFMA is sensitive to hydrolytic cleavage at its maleic acid moiety, and it is recommended that its samples should be stored under refrigerated and light-free conditions, and under inert environment.
基金National Heart,Lung,and Blood Institute,Grant/Award Number:R41HL140919-01Sandra K.and David L.Gilliland Chair in Nuclear Pharmacy。
文摘Background:Drug-induced cardiomyopathy is a significant medical problem.Clinical diagnosis of myocardial injury is based on initial electrocardiogram,levels of circulating biomarkers,and perfusion imaging with single photon emission computed tomography(SPECT).Positron emission tomography(PET)is an alternative imaging modality that provides better resolution and sensitivity than SPECT,improves diagnostic accuracy,and allows therapeutic monitoring.The objective of this study was to assess the detection of drug-induced cardiomyopathy by PET using 2-deoxy-2-[^18F]fluoro-D-glucose(FDG)and compare it with the conventional SPECT technique with[^99m Tc]-Sestamibi(MIBI).Methods:Cardiomyopathy was induced in Sprague Dawley rats using high-dose isoproterenol.Nuclear[^18F]FDG/PET and[^99m Tc]MIBI/SPECT were performed before and after isoproterenol administration.[^18F]FDG(0.1 mCi,200-400μL)and[^99m Tc]MIBI(2 mCi,200-600μL)were administered via the tail vein and imaging was performed 1 hour postinjection.Isoproterenol-induced injury was confirmed by the plasma level of cardiac troponin and triphenyltetrazolium chloride(TTC)staining.Results:Isoproterenol administration resulted in an increase in circulating cardiac troponin I and showed histologic damage in the myocardium.Visually,preisoproterenol and postisoproterenol images showed alterations in cardiac accumulation of[^18F]FDG,but not of[^99m Tc]MIBI.Image analysis revealed that myocardial uptake of[^18F]FDG reduced by 60%after isoproterenol treatment,whereas that of[^99m Tc]MIBI decreased by 45%.Conclusion:We conclude that[^18F]FDG is a more sensitive radiotracer than[^99m Tc]MIBI for imaging of drug-induced cardiomyopathy.We theorize that isoproterenolinduced cardiomyopathy impacts cellular metabolism more than perfusion,which results in more substantial changes in[^18F]FDG uptake than in[^99m Tc]MIBI accumulation in cardiac tissue.
