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Journal of Chromatography. B,... May 2024Trace amines are powerful neuromodulators influencing the release and reuptake of catecholamines. These low concentrated endogenous amines impact mood, cognition, and...
OBJECTIVES
Trace amines are powerful neuromodulators influencing the release and reuptake of catecholamines. These low concentrated endogenous amines impact mood, cognition, and hormone regulation. Dysregulation of trace amines have been associated with a variety of diseases, such as schizophrenia, Parkinson's disease, migraine, depression and more. Succesfull simultaneous quantification of trace amines, their precursors and metabolites would benefit both research and patient care. Since these compounds have various functional groups and are present in biological matrices with large concentration difference, their simultaneous quantification is an analytical challenge. Our goal was to develop a highly sensitive LC-MS/MS assay to simultaneously quantify trace amines, their precursors and metabolites in plasma.
METHODS
Our method is based on a simple two-step in-matrix derivatization protocol: propionic anhydride (PA) and 3-Ethyl-1-[3-(dimethylamino)propyl]carbodiimide (EDC) in combination with 2,2,2-trifluoroethylamine (TFEA) followed by online solid phase extraction combined with LC-MS/MS. Fifteen metabolites can be measured simultaneously, three precursors, eight trace amines and four metabolites. Validation of this method was performed according to international validation guidelines. The pre-analytical stability of trace amines was assessed.
RESULTS
This novel method was successful in quantifying trace amines, their precursors, and metabolites in plasma. Using just 50 µl human plasma, we were able to accomplish limit of quantification for 2-phenylethylamine and N-methyl-phenylethylamine of 0.2 nmol/L and 0.1 nmol/L for tyramine and n-methyltyramine. Inter-and intra-assay imprecision was < 15 % for all analytes. Stability assessment showed susceptibility of certain trace amines e.g. 2-phenylethylamine and N-methyl-phenylethylamine to enzymatic degradation in plasma. The addition of the monoamine oxidase inhibitor pargyline to plasma prevented this enzymatic degradation.
CONCLUSIONS
We developed a novel LC-MS/MS method that1) uses a new double derivatization technique, 2) is automated with online SPE, 3) uses far less sample volume then previous methods and 4) detects more components in the same sample (eight trace amines, three precursors, and four metabolites) with high specificity and selectivity. Furthermore, addition of MAO A/B inhibitor prevents degradation and guarantees more accurate quantification of trace amines.
Topics: Humans; Tandem Mass Spectrometry; Reproducibility of Results; Amines; Chromatography, Liquid; Limit of Detection; Linear Models; Solid Phase Extraction
PubMed: 38583227
DOI: 10.1016/j.jchromb.2024.124098 -
Oncology Reports Oct 2013Chemotherapy is one of the therapeutic strategies that has been used for the inhibition of cancer cell proliferation in several types of cancer, including prostate...
Chemotherapy is one of the therapeutic strategies that has been used for the inhibition of cancer cell proliferation in several types of cancer, including prostate cancer. Although monoamine oxidase (MAO) inhibitors, phytoestrogen and antioxidants used in chemotherapy have been systematically studied, their effects on cancer cell growth remain to be fully understood. The purpose of this study was to investigate the effects of the MAO inhibitors, pargyline and tranylcypromine on cell survival in human prostate carcinoma (LNCaP-LN3) cells. After treating LNCaP-LN3 cells with pargyline or tranylcypromine, we examined cell proliferation, cell cycle pattern, apoptosis and the expression levels of apoptosis-related genes. The proliferation of cells exposed to pargyline decreased in a dose- and time-dependent manner, while tranylcypromine-treated cells showed the opposite results. Treatment with pargyline significantly induced cell cycle arrest at the G1 phase compared to the control and tranylcypromine-treated cells. In addition, pargyline induced an increase in the cell death rate by promoting apoptosis; however, tranylcypromine had no effect on LNCaP-LN3 cells. Based on our results, we suggest that pargyline is more powerful than tranylcypromine for the treatment of human prostate cancer.
Topics: Apoptosis; Caspase 3; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Cell Survival; Cytochromes c; G1 Phase Cell Cycle Checkpoints; Humans; Male; Monoamine Oxidase Inhibitors; Pargyline; Prostatic Neoplasms; Proto-Oncogene Proteins c-bcl-2; RNA, Messenger; Tranylcypromine
PubMed: 23900512
DOI: 10.3892/or.2013.2635 -
Molecules (Basel, Switzerland) May 2020Previously synthesized novel chalcone oxime ethers (COEs) were evaluated for inhibitory activities against monoamine oxidases (MAOs) and acetylcholinesterase (AChE)....
Previously synthesized novel chalcone oxime ethers (COEs) were evaluated for inhibitory activities against monoamine oxidases (MAOs) and acetylcholinesterase (AChE). Twenty-two of the 24 COEs synthesized, except and , had potent and/or significant selective inhibitory effects on MAO-B. potently inhibited MAO-B with an IC value of 0.018 µM, which was 105, 2.3, and 1.1 times more potent than clorgyline, lazabemide, and pargyline (reference drugs), respectively. , and were also active against MAO-B, both had an IC value of 0.028 µM, which was 67 and 1.5 times lower than those of clorgyline and lazabemide, respectively. Most of the COEs exhibited weak inhibitory effects on MAO-A and AChE. most potently inhibited MAO-A (IC = 0.88 µM) and also significantly inhibited MAO-B (IC = 0.13 µM), and it could be considered as a potential nonselective MAO inhibitor. and inhibited AChE with IC values of 5.35 and 4.39 µM, respectively. The selectivity index (SI) of for MAO-B was higher than that of (SI = 778.6 vs. 222.2), but the IC value (0.028 µM) was slightly lower than that of (0.018 µM). In reversibility experiments, inhibitions of MAO-B by and were recovered to the levels of reference reversible inhibitors and both competitively inhibited MAO-B, with K values of 0.0075 and 0.010 µM, respectively. Our results show that and are potent, selective MAO-B inhibitors, and is a candidate of dual-targeting molecule for MAO-B and AChE.
Topics: Acetylcholinesterase; Chalcone; Cholinesterase Inhibitors; Ethers; Humans; Kinetics; Monoamine Oxidase; Monoamine Oxidase Inhibitors; Oximes
PubMed: 32443652
DOI: 10.3390/molecules25102356 -
Organic Letters Jul 2021We report here a three-component, Cu(I)-catalyzed hexadehydro-Diels-Alder (HDDA) benzyne 1,2-difunctionalization reaction. This protocol allowed the introduction of two...
We report here a three-component, Cu(I)-catalyzed hexadehydro-Diels-Alder (HDDA) benzyne 1,2-difunctionalization reaction. This protocol allowed the introduction of two different carbon-based substituents onto the in situ-generated benzyne. These substituents were terminal monoynes or diynes partnered with propargylic, benzylic, or allylic chlorides. An example of a sequential HDDA reaction is demonstrated using the product of a 1,3-diyne and a propargylic halide, itself a newly created HDDA precursor.
Topics: Benzene Derivatives; Catalysis; Copper; Cycloaddition Reaction; Diynes; Molecular Structure; Pargyline
PubMed: 34180676
DOI: 10.1021/acs.orglett.1c01788 -
In Vivo (Athens, Greece) 2004Since novel synthesized deprenyl-related derivatives of nitroxides, named "JSAKs", have been shown to possess antioxidative properties, their cytotoxicity on...
Since novel synthesized deprenyl-related derivatives of nitroxides, named "JSAKs", have been shown to possess antioxidative properties, their cytotoxicity on neuronal-like PC-12 cells line was examined. The antiproliferative effect of two selected JSAKs was examined and expressed as IC10, IC50 and IC90, and compared with those of the parent nitroxide (Nx-640), model nitroxide TEMPO and deprenyl. There were substantial differences in the dose-dependence of all the observed antiproliferative and cytotoxic effects. Compared to anticancer drugs and apoptosis inducers with topoisomerase inhibitor properties (etoposide and camptothecin), novel compounds displayed cytotoxicity at considerably higher concentrations. The dose-dependent anti-apoptotic potency of JSAKs and Nx-640 was also investigated and compared to TEMPO and deprenyl effects. The observed structure-dependent correlation was very encouraging and prompted us to screen and to compare the in vivo time-dependent effects of JSAKs, Nx-640 and deprenyl administration on the rat intact nigrostriatal neurocytes. TH-immunochemistry was applied as the test method and marker for the changes in the state of the rat catecholaminergic system, also giving evidence that low-toxic and cell-permeable JSAKs can cross the blood-brain barrier, which is the mandatory prerequisite for the therapeutic application of antioxidants and drugs to the brain. Taken together, it can be concluded with great certainty that novel deprenyl-related JSAKs might be especially good candidates for further anticancer investigations in vitro and in vivo and future pharmacological applications.
Topics: Animals; Antioxidants; Apoptosis; Cell Survival; Dopamine; Dose-Response Relationship, Drug; Female; Neurons; Neuroprotective Agents; Nitrogen Oxides; PC12 Cells; Pargyline; Propylamines; Rats; Rats, Inbred BUF; Structure-Activity Relationship
PubMed: 15113044
DOI: No ID Found -
Biochemistry Apr 2011TEMPO-substituted pargyline analogues differentially inhibit recombinant human monoamine oxidase A (MAO A) and B (MAO B) in intact yeast mitochondria, suggesting these... (Comparative Study)
Comparative Study
TEMPO-substituted pargyline analogues differentially inhibit recombinant human monoamine oxidase A (MAO A) and B (MAO B) in intact yeast mitochondria, suggesting these membrane-bound enzymes are located on differing faces of the mitochondrial outer membrane [Upadhyay, A., and Edmondson, D. E. (2009) Biochemistry 48, 3928]. This approach is extended to the recombinant rat enzymes and to rat liver mitochondria. The differential specificities exhibited for human MAO A and MAO B by the m- and p-amido TEMPO pargylines are not as absolute with the rat enzymes. Similar patterns of reactivity are observed for rat MAO A and B in mitochondrial outer membrane preparations expressed in Pichia pastoris or isolated from rat liver. In intact yeast mitochondria, recombinant rat MAO B is inhibited by the pargyline analogue whereas MAO A activity shows no inhibition. Intact rat liver mitochondria exhibit an inhibition pattern opposite to that observed in yeast where MAO A is inhibited and MAO B activity is unaffected. Protease inactivation studies show specificity in that MAO A is sensitive to trypsin whereas MAO B is sensitive to β-chymotrypsin. In intact mitochondrial preparations, MAO A is readily inactivated in rat liver but not in yeast upon trypsin treatment and MAO B is readily inactivated by β-chymotrypsin in yeast but not in rat liver. These data show MAO A is oriented on the cytosolic face and MAO B is situated on the surface facing the intermembrane space of the mitochondrial outer membrane in rat liver. The differential mitochondrial outer membrane topology of MAO A and MAO B is relevant to their inhibition by drugs designed to be cardioprotectants or neuroprotectants.
Topics: Animals; Chymotrypsin; Humans; Hydrolysis; Kinetics; Mitochondria, Liver; Mitochondrial Membranes; Monoamine Oxidase; Monoamine Oxidase Inhibitors; Pargyline; Pichia; Piperidines; Rats; Recombinant Proteins; Species Specificity; Spin Labels; Substrate Specificity; Trypsin
PubMed: 21341713
DOI: 10.1021/bi101722b -
Breast Cancer Research : BCR Jul 2012The estrogen receptor (ER) co-regulator proline glutamic acid and leucine-rich protein 1 (PELP1) is a proto-oncogene that modulates epigenetic changes on ER target gene...
INTRODUCTION
The estrogen receptor (ER) co-regulator proline glutamic acid and leucine-rich protein 1 (PELP1) is a proto-oncogene that modulates epigenetic changes on ER target gene promoters via interactions with lysine-specific histone demethylase 1 (KDM1). In this study, we assessed the therapeutic potential of targeting the PELP1-KDM1 axis in vivo using liposomal (1,2-dioleoyl-sn-glycero-3-phosphatidylcholine; DOPC) siRNA to downregulate PELP1 expression and KDM1 inhibitors, pargyline and N-((1S)-3-(3-(trans-2-aminocyclopropyl)phenoxy)-1-(benzylcarbamoyl)propyl)benzamide using preclinical models.
METHODS
Preclinical xenograft models were used to test the efficacy of drugs in vivo. Ki-67 and terminal deoxynucleotidyl transferase dUTP nick end-labeling immunohistochemical analysis of epigenetic markers was performed on tumor tissues. The in vitro effect of PELP1-KDM axis blockers was tested using proliferation, reporter gene, chromatin immunoprecipitation and real-time RT-PCR assays. The efficacy of the KDM1 targeting drugs alone or in combination with letrozole and tamoxifen was tested using therapy-resistant model cells.
RESULTS
Treatment of ER-positive xenograft-based breast tumors with PELP1-siRNA-DOPC or pargyline reduced tumor volume by 58.6% and 62%, respectively. In a postmenopausal model, in which tumor growth is stimulated solely by local estrogen synthesis, daily pargyline treatment reduced tumor volume by 78%. Immunohistochemical analysis of excised tumors revealed a combined decrease in cellular proliferation, induction of apoptosis and upregulation of inhibitory epigenetic modifications. Pharmacological inhibition of KDM1 in vitro increased inhibitory histone mark dimethylation of histone H3 at lysine 9 (H3K9me2) and decreased histone activation mark acetylation of H3K9 (H3K9Ac) on ER target gene promoters. Combining KDM1 targeting drugs with current endocrine therapies substantially impeded growth and restored sensitivity of therapy-resistant breast cancer cells to treatment.
CONCLUSION
Our results suggest inhibition of PELP1-KDM1-mediated histone modifications as a potential therapeutic strategy for blocking breast cancer progression and therapy resistance.
Topics: Animals; Benzamides; Breast Neoplasms; Carcinogens; Cell Line, Tumor; Cell Proliferation; Co-Repressor Proteins; Cyclopropanes; Drug Resistance, Neoplasm; Epigenesis, Genetic; Estrogens; Female; Gene Knockdown Techniques; Histone Demethylases; Histones; Humans; Mice; Molecular Targeted Therapy; Pargyline; Proto-Oncogene Mas; Transcription Factors
PubMed: 22812534
DOI: 10.1186/bcr3229 -
British Journal of Pharmacology Mar 19921. We compared three new catechol O-methyltransferase (COMT) inhibitors (OR-611, Ro 40-7592 and CGP 28014; 10 and 30 mg kg-1, i.p.) in male rats given levodopa (L-DOPA,... (Comparative Study)
Comparative Study
1. We compared three new catechol O-methyltransferase (COMT) inhibitors (OR-611, Ro 40-7592 and CGP 28014; 10 and 30 mg kg-1, i.p.) in male rats given levodopa (L-DOPA, 50 mg kg-1, i.p.) and carbidopa ((-)-L-alpha-methyl dopa, 50 mg kg-1, i.p.). In some studies pretreatment with pargyline (80 mg kg-1, i.p.) was used to block the function of monoamine oxidase (MAO). 2. Decreases of hypothalamic and striatal 3-O-methyl-dopa (3-OMD) levels were used as measures of the inhibition of peripheral COMT. The inhibition of brain COMT activity was estimated by decreases of hypothalamic and striatal homovanillic acid (HVA) and 3-methoxytyramine (3-MT; after pargyline) levels. 3. The three COMT inhibitors studied had different individual characteristics. OR-611 was primarily a peripherally acting COMT inhibitor, decreasing 3-OMD levels in the striatum (to 31-52%) and in the hypothalamus (to 16-27%) both in the control and pargyline-treated animals at 1 and 3 h. It did not have any effect on brain HVA and 3-MT. 3. Ro 40-7592 was a broad spectrum COMT inhibitor decreasing striatal and hypothalamic 3-OMD (always to less than 30%), HVA (to less than 50%) and 3-MT levels (to less than 23%) significantly both at 1 and 3 h. It was more potent than OR-611. 4. CGP 28014 functioned as a weak COMT inhibitor in the periphery inhibiting 3-OMD formation only at 3 h. In contrast, it was fairly potent in decreasing the brain HVA and 3-MT levels at 1 h (to 37-22% and 42-35% in the striatum, and to 57-33% and 64-35% in the hypothalamus, respectively) but not at 3 h. Since CGP 28014, unlike OR-611 and Ro 40-7592, did not generally increase the brain DOPA, dopamine or DOPAC levels, it was not a typical COMT inhibitor.
Topics: Amidines; Animals; Benzophenones; Biogenic Monoamines; Brain; Carbidopa; Catechol O-Methyltransferase Inhibitors; Catechols; Corpus Striatum; Homovanillic Acid; Hypothalamus; Levodopa; Male; Methyldopa; Nitriles; Nitrophenols; Pyridones; Rats; Rats, Inbred Strains; Tolcapone
PubMed: 1628144
DOI: 10.1111/j.1476-5381.1992.tb09020.x -
PeerJ 2016Harmine is the -carboline alkaloid with the highest concentration in the psychotropic plant decoction Ayahuasca. In rodents, classical antidepressants reverse the...
Harmine is the -carboline alkaloid with the highest concentration in the psychotropic plant decoction Ayahuasca. In rodents, classical antidepressants reverse the symptoms of depression by stimulating neuronal proliferation. It has been shown that Ayahuasca presents antidepressant effects in patients with depressive disorder. In the present study, we investigated the effects of harmine in cell cultures containing human neural progenitor cells (hNPCs, 97% nestin-positive) derived from pluripotent stem cells. After 4 days of treatment, the pool of proliferating hNPCs increased by 71.5%. Harmine has been reported as a potent inhibitor of the dual specificity tyrosine-phosphorylation-regulated kinase (DYRK1A), which regulates cell proliferation and brain development. We tested the effect of analogs of harmine, an inhibitor of DYRK1A (INDY), and an irreversible selective inhibitor of monoamine oxidase (MAO) but not DYRK1A (pargyline). INDY but not pargyline induced proliferation of hNPCs similarly to harmine, suggesting that inhibition of DYRK1A is a possible mechanism to explain harmine effects upon the proliferation of hNPCs. Our findings show that harmine enhances proliferation of hNPCs and suggest that inhibition of DYRK1A may explain its effects upon proliferation and antidepressant effects .
PubMed: 27957390
DOI: 10.7717/peerj.2727 -
British Journal of Pharmacology Mar 19791. Pargyline (100 mg/kg) increased the concentration of cerebral noradrenaline dopamine and 5-hydroxytryptamine in the mouse. Amphetamine (5 mg/kg) reduced the...
1. Pargyline (100 mg/kg) increased the concentration of cerebral noradrenaline dopamine and 5-hydroxytryptamine in the mouse. Amphetamine (5 mg/kg) reduced the concentration of noradrenaline and increased the concentrations of 5-hydroxytryptamine and dopamine. 2. When amphetamine was administered 4 h after an injection of pargyline, the effect of the sympathomimetic drug on the concentrations of noradrenaline and 5-hydroxytryptamine was not altered. The effect on the dopamine content was reversed, amphetamine causing a decrease instead of an increase. 3. Pargyline increased the concentration of cerebral glycogen, whereas amphetamine caused a decrease. 4. The administration of amphetamine 4 h after pargyline resulted in a decrease in brain glycogen similar to that seen after amphetamine alone. 5. These results suggest that the potentiation of the effect of amphetamine on animal behaviour by pretreatment with an inhibitor of monoamine oxidase is not mediated through a central action on noradrenaline release. 6. Amphetamine-induced glycogenolysis was antagonized by 71% by desmethylimipramine (10 mg/kg). 7. The change in glycogen concentration as a function of time after an injection of amphetamine was not modified when 2 consecutive doses of amphetamine were given with an interval between doses of 30 minutes.
Topics: Animals; Biogenic Amines; Body Temperature; Brain; Desipramine; Dextroamphetamine; Glycogen; Male; Mice; Pargyline; Time Factors
PubMed: 427324
DOI: 10.1111/j.1476-5381.1979.tb07856.x