-
International Journal of Molecular... Dec 2022Dysregulated brain-derived neurotrophic factor (BDNF)/tropomyosin receptor kinase B (TrkB) signalling is implicated in several neurodegenerative diseases, including...
Dysregulated brain-derived neurotrophic factor (BDNF)/tropomyosin receptor kinase B (TrkB) signalling is implicated in several neurodegenerative diseases, including Alzheimer's disease. A failure of neurotrophic support may participate in neurodegenerative mechanisms, such as ferroptosis, which has likewise been implicated in this disease class. The current study investigated whether modulators of TrkB signalling affect ferroptosis. Cell viability, C11 BODIPY, and cell-free oxidation assays were used to observe the impact of TrkB modulators, and an immunoblot assay was used to detect TrkB expression. TrkB modulators such as agonist BDNF, antagonist ANA-12, and inhibitor K252a did not affect RSL3-induced ferroptosis sensitivity in primary cortical neurons expressing detectable TrkB receptors. Several other modulators of the TrkB receptor, including agonist 7,8-DHF, activator phenelzine sulphate, and inhibitor GNF-5837, conferred protection against a range of ferroptosis inducers in several immortalised neuronal and non-neuronal cell lines, such as N27 and HT-1080 cells. We found these immortalised cell lines lack detectable TrkB receptor expression, so the anti-ferroptotic activity of these TrkB modulators was most likely due to their inherent radical-trapping antioxidant properties, which should be considered when interpreting their experimental findings. These modulators or their variants could be potential anti-ferroptotic therapeutics for various diseases.
Topics: Brain-Derived Neurotrophic Factor; Receptor, trkB; Signal Transduction; Neurons; Cell Survival
PubMed: 36555849
DOI: 10.3390/ijms232416205 -
International Journal of Molecular... Sep 2019Acute kidney injury (AKI) refers to an abrupt decrease in kidney function. It affects approximately 7% of all hospitalized patients and almost 35% of intensive care... (Review)
Review
Acute kidney injury (AKI) refers to an abrupt decrease in kidney function. It affects approximately 7% of all hospitalized patients and almost 35% of intensive care patients. Mortality from acute kidney injury remains high, particularly in critically ill patients, where it can be more than 50%. The primary causes of AKI include ischemia/reperfusion (I/R), sepsis, or nephrotoxicity; however, AKI patients may present with a complicated etiology where many of the aforementioned conditions co-exist. Multiple bio-markers associated with renal damage, as well as metabolic and signal transduction pathways that are involved in the mediation of renal dysfunction have been identified as a result of the examination of models, patient samples, and clinical data of AKI of disparate etiologies. These discoveries have enhanced our ability to diagnose AKIs and to begin to elucidate the mechanisms involved in their pathogenesis. Studies in our laboratory revealed that the expression and activity of spermine/spermidine N-acetyltransferase (SAT1), the rate-limiting enzyme in polyamine back conversion, were enhanced in kidneys of rats after I/R injury. Additional studies revealed that the expression of spermine oxidase (SMOX), another critical enzyme in polyamine catabolism, is also elevated in the kidney and other organs subjected to I/R, septic, toxic, and traumatic injuries. The maladaptive role of polyamine catabolism in the mediation of AKI and other injuries has been clearly demonstrated. This review will examine the biochemical and mechanistic basis of tissue damage brought about by enhanced polyamine degradation and discuss the potential of therapeutic interventions that target polyamine catabolic enzymes or their byproducts for the treatment of AKI.
Topics: Acetyltransferases; Acute Kidney Injury; Animals; Biomarkers; Gene Expression; Gene Expression Regulation, Enzymologic; Humans; Metabolic Networks and Pathways; Oxidoreductases Acting on CH-NH Group Donors; Polyamines; Polyamine Oxidase
PubMed: 31561575
DOI: 10.3390/ijms20194790 -
Clinical Pharmacology : Advances and... 2014The subject of this literature review is the alleged relationship between L-tyrosine, phenelzine, and hypertensive crisis. Phenelzine (Nardil(®)) prescribing... (Review)
Review
The subject of this literature review is the alleged relationship between L-tyrosine, phenelzine, and hypertensive crisis. Phenelzine (Nardil(®)) prescribing information notes: "The potentiation of sympathomimetic substances and related compounds by MAO inhibitors may result in hypertensive crises (see WARNINGS). Therefore, patients being treated with NARDIL should not take […] L-tyrosine […]". Interest in the scientific foundation of this claim was generated during routine patient care. A comprehensive literature search of Google Scholar and PubMed revealed no reported cases of hypertensive crisis associated with concomitant administration of L-tyrosine and phenelzine. Review of current US Food and Drug Administration nutritional guidelines relating to ongoing phenelzine studies reveals no mention and requires no consideration of L-tyrosine ingestion in combination with phenelzine. This paper is intended to provide an objective review of the science to then allow the reader to formulate the final opinion.
PubMed: 25092999
DOI: 10.2147/CPAA.S67271 -
BMC Pharmacology & Toxicology Dec 2023The main purpose was to evaluate the efficacy and tolerability of different medications used to treat bulimia nervosa (BN). (Meta-Analysis)
Meta-Analysis
OBJECTIVE
The main purpose was to evaluate the efficacy and tolerability of different medications used to treat bulimia nervosa (BN).
METHODS
Randomized controlled trials (RCTs) were identified from published sources through searches in PubMed, Cochrane Library, Web of Science, and Embase from inception to November 2022. Primary outcomes were changes in the frequency of binge eating episodes and vomiting episodes from baseline to endpoint. Secondary outcomes were differences in the improvement of scores in depressive symptoms, tolerability (dropout due to adverse events) and weight change.
RESULTS
The literature search ultimately included 11 drugs, 33 studies and 6 types of drugs, 8 trials with TCAs (imipramine, desipramine), 14 with SSRIs (fluoxetine, citalopram and fluvoxamine), 6 with MAOIs (phenelzine, moclobemide and brofaromine), 3 with antiepileptic drugs (topiramate), 1 with mood stabilizers (lithium), and 1 with amphetamine-type appetite suppressant (fenfluramine). The reduction in binge eating episodes was more likely due to these drugs than the placebo, and the SMD was -0.4 (95% CI -0.61 ~ -0.19); the changes in the frequency of vomiting episodes (SMD = -0.16, 95% CI -0.3 ~ -0.03); weight (WMD = -3.05, 95% CI -5.97 ~ -0.13); and depressive symptoms (SMD = -0.32, 95% CI -0.51 ~ -0.13). However, no significant difference was found in dropout due to adverse events (RR = 1.66, 95% CI 1.14 ~ 2.41).
CONCLUSIONS
This meta-analysis indicates that most pharmacotherapies decreased the frequency of binge-eating and vomiting episodes, body weight, and depressive symptoms in BN patients, but the efficacy was not significant. In each drug the efficacy is different, treating different aspects, different symptoms to improve the clinical performance of bulimia nervosa.
Topics: Humans; Bulimia Nervosa; Bulimia; Fluoxetine; Selective Serotonin Reuptake Inhibitors; Vomiting
PubMed: 38042827
DOI: 10.1186/s40360-023-00713-7 -
Pathogens (Basel, Switzerland) Apr 2021Non-typhoidal ingeniously scavenges energy for growth from tyramine (TYR) and d-glucuronic acid (DGA), both of which occur in the host as the metabolic byproducts of...
Non-typhoidal ingeniously scavenges energy for growth from tyramine (TYR) and d-glucuronic acid (DGA), both of which occur in the host as the metabolic byproducts of the gut microbial metabolism. A critical first step in energy scavenging from TYR and DGA in involves TYR-oxidation via TYR-oxidoreductase and production of free-DGA via β-glucuronidase (GUS)-mediated hydrolysis of d-glucuronides (conjugated form of DGA), respectively. Here, we report that utilizes TYR and DGA as sole sources of energy in a serotype-independent manner. Using colorimetric and radiometric approaches, we report that genes , , and encode TYR-oxidoreductases. Some serotypes produce GUS, thus can also scavenge energy from d-glucuronides. We repurposed phenelzine (monoaminoxidase-inhibitor) and amoxapine (GUS-inhibitor) to inhibit the TYR-oxidoreductases and GUS encoded by , respectively. We show that phenelzine significantly inhibits the growth of by inhibiting TYR-oxidoreductases SEN2971, SEN3065, and SEN2426. Similarly, amoxapine significantly inhibits the growth of by inhibiting GUS-mediated hydrolysis of d-glucuronides. Because TYR and DGA serve as potential energy sources for growth in vivo, the data and the novel approaches used here provides a better understanding of the role of TYR and DGA in pathogenesis and nutritional virulence.
PubMed: 33924374
DOI: 10.3390/pathogens10040469 -
Cellular and Molecular Neurobiology Jan 2022Phenelzine (PLZ) is a monoamine oxidase (MAO)-inhibiting antidepressant with anxiolytic properties. This multifaceted drug has a number of pharmacological and... (Review)
Review
Phenelzine (PLZ) is a monoamine oxidase (MAO)-inhibiting antidepressant with anxiolytic properties. This multifaceted drug has a number of pharmacological and neurochemical effects in addition to inhibition of MAO, and findings on these effects have contributed to a body of evidence indicating that PLZ also has neuroprotective/neurorescue properties. These attributes are reviewed in this paper and include catabolism to the active metabolite β-phenylethylidenehydrazine (PEH) and effects of PLZ and PEH on the GABA-glutamate balance in brain, sequestration of reactive aldehydes, and inhibition of primary amine oxidase. Also discussed are the encouraging findings of the effects of PLZ in animal models of stroke, spinal cord injury, traumatic brain injury, and multiple sclerosis, as well other actions such as reduction of nitrative stress, reduction of the effects of a toxin on dopaminergic neurons, potential anticonvulsant actions, and effects on brain-derived neurotrophic factor, neural cell adhesion molecules, an anti-apoptotic factor, and brain levels of ornithine and N-acetylamino acids.
Topics: Animals; Antidepressive Agents; Monoamine Oxidase; Monoamine Oxidase Inhibitors; Neuroprotective Agents; Phenelzine; Rats; Rats, Sprague-Dawley
PubMed: 33839994
DOI: 10.1007/s10571-021-01078-3 -
Chemico-biological Interactions May 2019Phenelzine (β-phenylethylhydrazine) is a monoamine oxidase (MAO)-inhibiting antidepressant with anxiolytic properties. It possesses a number of important... (Review)
Review
Phenelzine (β-phenylethylhydrazine) is a monoamine oxidase (MAO)-inhibiting antidepressant with anxiolytic properties. It possesses a number of important pharmacological properties which may alter the effects of oxidative stress. After conducting a comprehensive literature search, the authors of this review paper aim to provide an overview and discussion of the mechanisms by which phenelzine may attenuate oxidative stress. It inhibits γ-aminobutyric acid (GABA) transaminase, resulting in elevated brain GABA levels, inhibits both MAO and primary amine oxidase and, due to its hydrazine-containing structure, reacts chemically to sequester a number of reactive aldehydes (e.g. acrolein and 4-hydroxy-2-nonenal) proposed to be implicated in oxidative stress in a number of neurodegenerative disorders. Phenelzine is unusual in that it is both an inhibitor of and a substrate for MAO, the latter action producing at least one active metabolite, β-phenylethylidenehydrazine (PEH). This metabolite inhibits GABA transaminase, is a very weak inhibitor of MAO but a strong inhibitor of primary amine oxidase, and sequesters aldehydes. Phenelzine may ameliorate the effects of oxidative stress by reducing formation of reactive metabolites (aldehydes, hydrogen peroxide, ammonia/ammonia derivatives) produced by the interaction of MAO with biogenic amines, by sequestering various other reactive aldehydes and by inhibiting primary amine oxidase. In PC12 cells treated with the neurotoxin MPP, phenelzine has been reported to reduce several adverse effects of MPP. It has also been reported to reduce lipid peroxidative damage induced in plasma and platelet proteins by peroxynitrite. In animal models, phenelzine has a neuroprotective effect in global ischemia and in cortical impact traumatic brain injury. Recent studies reported in the literature on the possible involvement of acrolein in spinal cord injury and multiple sclerosis indicate that phenelzine can attenuate adverse effects of acrolein in these models. Results from studies in our laboratories on effects of phenelzine and PEH on primary amine oxidase (which catalyzes formation of toxic aldehydes and is overexpressed in Alzheimer's disease), on sequestration of the toxic aldehyde acrolein, and on reduction of acrolein-induced toxicity in mouse cortical neurons are also reported.
Topics: Animals; Antidepressive Agents; Free Radical Scavengers; Humans; Molecular Structure; Monoamine Oxidase; Monoamine Oxidase Inhibitors; Oxidative Stress; Phenelzine
PubMed: 30857888
DOI: 10.1016/j.cbi.2019.03.003 -
Frontiers in Oncology 2022Lysine-Specific Demethylase-1 (LSD1) is overexpressed in breast cancer cells and facilitate mesenchymal properties which may contribute to therapeutic resistance and...
OBJECTIVE
Lysine-Specific Demethylase-1 (LSD1) is overexpressed in breast cancer cells and facilitate mesenchymal properties which may contribute to therapeutic resistance and cancer progression. The purpose of this study was to investigate the safety of combination, nab-paclitaxel and phenelzine, an irreversible LSD1 inhibitor in patients with metastatic breast cancer (mBC).
METHODS
Eligible patients with mBC were treated with nab-paclitaxel (100mg/m) weekly for 3 weeks with one week break in a 28-day cycle. Dose escalation of phenelzine followed the Cumulative Cohort Design and phenelzine treatment commenced from day 2 of first cycle. Eleven patients were screened, and eligible patients were enrolled in cohorts with the dose of phenelzine ranging from 45mg to 90mg.
RESULTS
The Optimum Biological Dose was established at 60mg of phenelzine daily in combination with nab-paclitaxel and considered as the recommended phase 2 dose. Most (95%) of adverse events were grade 1 or 2 with two grade 3 events being diarrhea and neutropenia at 45mg and 60mg phenelzine respectively, with no unexpected toxicity/deaths. Commonly reported toxicities were fatigue (n=4,50%), dizziness (n=6,75%), neutropenia (n=3,37.5%), peripheral neuropathy (n=3,37.5%), diarrhea (n=2,25%), and hallucination (n=2,25%). After a median follow up of 113 weeks, all patients showed disease progression on trial with 4 patients being alive at the time of data cut off, including one patient with triple negative breast cancer. Median progression-free survival was 34 weeks. Significant inhibition of LSD1 and suppression of mesenchymal markers in circulating tumor cells were noted.
CONCLUSION
Phenelzine in combination with nab-paclitaxel was well tolerated, without any unexpected toxicities in patients with mBC and demonstrated evidence of antitumor activity. For the first time, this proof-of-concept study showed inhibition of LSD1 suppressed mesenchymal markers, which are known to facilitate generation of cancer stem cells with metastatic potential. ClinicalTrials.Gov NCT03505528, UTN of U1111-1197-5518.
PubMed: 35719960
DOI: 10.3389/fonc.2022.862427 -
Photodermatology, Photoimmunology &... May 2023Lysine-specific histone demethylase 1 (KDM1A/LSD1) regulates multiple cellular functions, including cellular proliferation, differentiation, and DNA repair. KDM1A is...
BACKGROUND
Lysine-specific histone demethylase 1 (KDM1A/LSD1) regulates multiple cellular functions, including cellular proliferation, differentiation, and DNA repair. KDM1A is overexpressed in squamous cell carcinoma of the skin and inhibition of KDM1A can suppress cutaneous carcinogenesis. Despite the role of KDM1A in skin and DNA repair, the effect of KDM1A inhibition on cellular ultraviolet (UV) response has not been studied.
METHODS
The ability of KDM1A inhibitor bizine to modify cell death after UVA and UVB exposure was tested in normal human keratinocytes and melanocytes, HaCaT, and FaDu cell lines. KDM1A was also downregulated using shRNA and inhibited by phenelzine in HaCaT and FaDu cells to confirm the role of KDM1A in UVA response. In addition, cellular reactive oxygen species (ROS) changes were assessed by a lipid-soluble fluorescent indicator of lipid oxidation, and ROS-related gene regulation using qPCR. During photodynamic therapy (PDT) studies HaCaT and FaDu cells were treated with aminolaevulinic acid (5-ALA) or HPPH (2-[1-hexyloxyethyl]-2-devinyl pyropheophorbide-a) sodium and irradiated with 0-8 J/cm red LED light.
RESULTS
KDM1A inhibition sensitized cells to UVA radiation-induced cell death but not to UVB. KDM1A inhibition increased ROS generation as detected by increased lipid peroxidation and the upregulation of ROS-responsive genes. The effectiveness of both ALA and HPPH PDT significantly improved in vitro in HaCaT and FaDu cells after KDM1A inhibition.
CONCLUSION
KDM1A is a regulator of cellular UV response and KDM1A inhibition can improve PDT efficacy.
Topics: Humans; Aminolevulinic Acid; Histone Demethylases; Keratinocytes; Lipids; Photochemotherapy; Reactive Oxygen Species; Skin; Ultraviolet Rays
PubMed: 35968606
DOI: 10.1111/phpp.12826 -
Experimental Neurology Aug 2020Traumatic brain injury (TBI) results in mitochondrial dysfunction and induction of lipid peroxidation (LP). Lipid peroxidation-derived neurotoxic aldehydes such as 4-HNE... (Review)
Review
Protective effects of phenelzine administration on synaptic and non-synaptic cortical mitochondrial function and lipid peroxidation-mediated oxidative damage following TBI in young adult male rats.
Traumatic brain injury (TBI) results in mitochondrial dysfunction and induction of lipid peroxidation (LP). Lipid peroxidation-derived neurotoxic aldehydes such as 4-HNE and acrolein bind to mitochondrial proteins, inducing additional oxidative damage and further exacerbating mitochondrial dysfunction and LP. Mitochondria are heterogeneous, consisting of both synaptic and non-synaptic populations, with synaptic mitochondria being more vulnerable to injury-dependent consequences. The goal of these studies was to explore the hypothesis that interrupting secondary oxidative damage following TBI using phenelzine (PZ), an aldehyde scavenger, would preferentially protect synaptic mitochondria against LP-mediated damage in a dose- and time-dependent manner. Male Sprague-Dawley rats received a severe (2.2 mm) controlled cortical impact (CCI)-TBI. PZ (3-30 mg/kg) was administered subcutaneously (subQ) at different times post-injury. We found PZ treatment preserves both synaptic and non-synaptic mitochondrial bioenergetics at 24 h and that this protection is partially maintained out to 72 h post-injury using various dosing regimens. The results from these studies indicate that the therapeutic window for the first dose of PZ is likely within the first hour after injury, and the window for administration of the second dose seems to fall between 12 and 24 h. Administration of PZ was able to significantly improve mitochondrial respiration compared to vehicle-treated animals across various states of respiration for both the non-synaptic and synaptic mitochondria. The synaptic mitochondria appear to respond more robustly to PZ treatment than the non-synaptic, and further experimentation will need to be done to further understand these effects in the context of TBI.
Topics: Animals; Brain Injuries, Traumatic; Cerebral Cortex; Lipid Peroxidation; Male; Mitochondria; Neuroprotective Agents; Oxidative Stress; Phenelzine; Rats; Rats, Sprague-Dawley; Synapses
PubMed: 32325157
DOI: 10.1016/j.expneurol.2020.113322