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1.
Mol Psychiatry ; 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378926

RESUMO

Psilocybin, a naturally occurring, tryptamine alkaloid prodrug, is currently being investigated for the treatment of a range of psychiatric disorders. Preclinical reports suggest that the biological effects of psilocybin-containing mushroom extract or "full spectrum" (psychedelic) mushroom extract (PME), may differ from those of chemically synthesized psilocybin (PSIL). We compared the effects of PME to those of PSIL on the head twitch response (HTR), neuroplasticity-related synaptic proteins and frontal cortex metabolomic profiles in male C57Bl/6j mice. HTR measurement showed similar effects of PSIL and PME over 20 min. Brain specimens (frontal cortex, hippocampus, amygdala, striatum) were assayed for the synaptic proteins, GAP43, PSD95, synaptophysin and SV2A, using western blots. These proteins may serve as indicators of synaptic plasticity. Three days after treatment, there was minimal increase in synaptic proteins. After 11 days, PSIL and PME significantly increased GAP43 in the frontal cortex (p = 0.019; p = 0.039 respectively) and hippocampus (p = 0.015; p = 0.027) and synaptophysin in the hippocampus (p = 0.041; p = 0.05) and amygdala (p = 0.035; p = 0.004). PSIL increased SV2A in the amygdala (p = 0.036) and PME did so in the hippocampus (p = 0.014). In the striatum, synaptophysin was increased by PME only (p = 0.023). There were no significant effects of PSIL or PME on PSD95 in any brain area when these were analyzed separately. Nested analysis of variance (ANOVA) showed a significant increase in each of the 4 proteins over all brain areas for PME versus vehicle control, while significant PSIL effects were observed only in the hippocampus and amygdala and were limited to PSD95 and SV2A. Metabolomic analyses of the pre-frontal cortex were performed by untargeted polar metabolomics utilizing capillary electrophoresis - Fourier transform mass spectrometry (CE-FTMS) and showed a differential metabolic separation between PME and vehicle groups. The purines guanosine, hypoxanthine and inosine, associated with oxidative stress and energy production pathways, showed a progressive decline from VEH to PSIL to PME. In conclusion, our synaptic protein findings suggest that PME has a more potent and prolonged effect on synaptic plasticity than PSIL. Our metabolomics data support a gradient of effects from inert vehicle via chemical psilocybin to PME further supporting differential effects. Further studies are needed to confirm and extend these findings and to identify the molecules that may be responsible for the enhanced effects of PME as compared to psilocybin alone.

2.
Brain ; 134(Pt 3): 678-92, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21354971

RESUMO

Inflammation and oxidative stress are thought to promote tissue damage in multiple sclerosis. Thus, novel therapeutics enhancing cellular resistance to free radicals could prove useful for multiple sclerosis treatment. BG00012 is an oral formulation of dimethylfumarate. In a phase II multiple sclerosis trial, BG00012 demonstrated beneficial effects on relapse rate and magnetic resonance imaging markers indicative of inflammation as well as axonal destruction. First we have studied effects of dimethylfumarate on the disease course, central nervous system, tissue integrity and the molecular mechanism of action in an animal model of chronic multiple sclerosis: myelin oligodendrocyte glycoprotein induced experimental autoimmune encephalomyelitis in C57BL/6 mice. In the chronic phase of experimental autoimmune encephalomyelitis, preventive or therapeutic application of dimethylfumarate ameliorated the disease course and improved preservation of myelin, axons and neurons. In vitro, the application of fumarates increased murine neuronal survival and protected human or rodent astrocytes against oxidative stress. Application of dimethylfumarate led to stabilization of the transcription factor nuclear factor (erythroid-derived 2)-related factor 2, activation of nuclear factor (erythroid-derived 2)-related factor 2-dependent transcriptional activity and accumulation of NADP(H) quinoline oxidoreductase-1 as a prototypical target gene. Furthermore, the immediate metabolite of dimethylfumarate, monomethylfumarate, leads to direct modification of the inhibitor of nuclear factor (erythroid-derived 2)-related factor 2, Kelch-like ECH-associated protein 1, at cysteine residue 151. In turn, increased levels of nuclear factor (erythroid-derived 2)-related factor 2 and reduced protein nitrosylation were detected in the central nervous sytem of dimethylfumarate-treated mice. Nuclear factor (erythroid-derived 2)-related factor 2 was also upregulated in the spinal cord of autopsy specimens from untreated patients with multiple sclerosis. In dimethylfumarate-treated mice suffering from experimental autoimmune encephalomyelitis, increased immunoreactivity for nuclear factor (erythroid-derived 2)-related factor 2 was detected by confocal microscopy in neurons of the motor cortex and the brainstem as well as in oligodendrocytes and astrocytes. In mice deficient for nuclear factor (erythroid-derived 2)-related factor 2 on the same genetic background, the dimethylfumarate mediated beneficial effects on clinical course, axon preservation and astrocyte activation were almost completely abolished thus proving the functional relevance of this transcription factor for the neuroprotective mechanism of action. We conclude that the ability of dimethylfumarate to activate nuclear factor (erythroid-derived 2)-related factor 2 may offer a novel cytoprotective modality that further augments the natural antioxidant responses in multiple sclerosis tissue and is not yet targeted by other multiple sclerosis therapies.


Assuntos
Encefalomielite Autoimune Experimental/prevenção & controle , Fumaratos/uso terapêutico , Fator 2 Relacionado a NF-E2/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , 2',3'-Nucleotídeo Cíclico Fosfodiesterases/metabolismo , Aldeído Redutase/metabolismo , Animais , Antígenos de Diferenciação/metabolismo , Antioxidantes/metabolismo , Astrócitos/efeitos dos fármacos , Astrócitos/imunologia , Axônios/metabolismo , Axônios/patologia , Complexo CD3/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Cromatografia Líquida de Alta Pressão/métodos , Citocinas/metabolismo , Modelos Animais de Doenças , Embrião de Mamíferos , Encefalomielite Autoimune Experimental/etiologia , Feminino , Fumaratos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Glicoproteínas/efeitos adversos , Proteínas de Fluorescência Verde/genética , Humanos , Peróxido de Hidrogênio/farmacologia , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos C57BL , Neurônios Motores/citologia , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/metabolismo , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , Proteínas da Mielina/metabolismo , Glicoproteína Mielina-Oligodendrócito , NAD(P)H Desidrogenase (Quinona)/metabolismo , Fármacos Neuroprotetores/farmacologia , Proteínas Nogo , Estresse Oxidativo/efeitos dos fármacos , Fragmentos de Peptídeos/efeitos adversos , RNA Interferente Pequeno/farmacologia , Sono/fisiologia , Medula Espinal/citologia , Estatísticas não Paramétricas , Espectrometria de Massas em Tandem/métodos , Fatores de Tempo , Transfecção
3.
Biotechnol Bioeng ; 108(4): 977-82, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21404269

RESUMO

Monoclonal antibody (mAb) fragmentation can be a widespread problem across the biotechnology industry and there is a current need to better understand the underlying principles. Here, we report an example of a high-purity human IgG1 mAb prepared from CHO cells exhibiting fragmentation that can be attributed to residual proteolytic enzyme activity. The concomitant occurrence of proteolytic and non-proteolytic peptide bond cleavage is shown and the respective fragmentation patterns characterized using high-resolution LC-MS. Fragmentation rates are monitored by SE-HPLC and SDS-PAGE over the pH range 4-6 and characterized in the presence and absence of pepstatin A, an inhibitor of acidic proteases. After 20 days at 40°C, pH 4, ∼60% decrease in BIIB-mAb monomer peak occurred attributed to residual proteolytic activity. At pH 5, this value was ∼13%. These results have implications for formulation design studies and the interpretation of accelerated stability data. A simple method to screen for acidic protease activity using the proteolytic enzyme inhibitor pepstatin A is described.


Assuntos
Anticorpos Monoclonais/metabolismo , Células CHO/enzimologia , Endopeptidases/metabolismo , Imunoglobulina G/metabolismo , Animais , Anticorpos Monoclonais/isolamento & purificação , Cricetinae , Cricetulus , Humanos , Imunoglobulina G/isolamento & purificação
4.
Redox Biol ; 41: 101927, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33690107

RESUMO

The molecular events that modulate the progression of monoclonal gammopathy of undetermined significance of the immunoglobulin M class (IgM-MGUS) to Waldenstrom Macroglobulinemia (WM) are mostly unknown. We implemented comparative proteomics and metabolomics analyses on patient serum samples to identify differentially expressed molecules crucial to the progression from IgM-MGUS to WM. Our data identified altered lipid metabolism as a discriminating factor between MGUS, WM, and matched normal controls. Levels of many fatty acids, including polyunsaturated fatty acids and dicarboxylic acids, were significantly downregulated in WM sera when compared to MGUS. These reductions were associated with diminished 15-LOX and PPAR protein expression and increased 5-LOX and GPX4 expression in WM versus MGUS patients' samples. Furthermore, WM serum samples showed increased lipid peroxidation compared to MGUS. Treatment with IL-6 or TNFα, upstream regulators of differentially expressed proteins between MGUS and WM, increased lipid absorption and lipid peroxidation in WM cell lines. Knock-down of 15-LOX expression increased WM cell survival, an effect accompanied by increased 5-LOX and GPX4 expression. In summary, our data show that reduced fatty acid and lipid metabolite levels in the serum of the WM patients are associated with increased lipid peroxidation and that downregulation of 15-LOX increases the survival of WM cells. These data are highly significant in identifying the biomarkers of disease progression and designing targeted therapeutic intervention.


Assuntos
Gamopatia Monoclonal de Significância Indeterminada , Paraproteinemias , Macroglobulinemia de Waldenstrom , Humanos , Imunoglobulina M , Metabolismo dos Lipídeos
5.
Redox Biol ; 36: 101657, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32763516

RESUMO

Metabolic reprogramming is a hallmark of cancer cells. In Waldenstrom Macroglobulinemia (WM), the infiltration of IgM-secreting lymphoplamacytic cells into the bone marrow (BM) could shift the homeostasis of proteins and metabolites towards a permissive niche for tumor growth. Here, we investigated whether alerted metabolic pathways contribute to the pathobiology of WM and whether the cytokine composition of the BM promotes such changes. Metabolomics analysis on WM patients and normal donors' serum samples revealed a total of 75 metabolites that were significantly altered between two groups. While these metabolites belonged to amino acids, glucose, glutathione and lipid metabolism pathways, the highest number of the differentially expressed metabolites belonged to glutathione metabolism. Proteomics analysis and immunohistochemical staining both confirmed the increased protein levels mediating glutathione metabolism, including GCLC, MT1X, QPCT and GPX3. Moreover, treatment with IL-6 and IL-21, cytokines that induce WM cell proliferation and IgM secretion, increased gene expression of the amino acid transporters mediating glutathione metabolism, including ASCT2, SLC7A11 and 4F2HC, indicating that cytokines in the WM BM could modulate glutathione metabolism. Glutathione synthesis inhibition using Buthionine sulphoximine (BSO) significantly reduced WM cells proliferation in vitro, accompanied with decreased NFκB-p65 and MAPK-p38 phosphorylation. Moreover, BSO treatment significantly reduced the tumor growth rate in a WM xenograft model, further highlighting the role of glutathione metabolism in promoting tumor growth and proliferation. In summary, our data highlight a central role for glutathione metabolism in WM pathobiology and indicate that intervening with the metabolic processes could be a potential therapy for WM patients.


Assuntos
Macroglobulinemia de Waldenstrom , Medula Óssea , Proliferação de Células , Glutationa , Humanos , Macroglobulinemia de Waldenstrom/tratamento farmacológico , Macroglobulinemia de Waldenstrom/genética
7.
J Biomol Screen ; 11(7): 828-35, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16956997

RESUMO

A subset of the compound repository for lead identification at Biogen Idec was characterized for its chemical stability over a 3-year period. Compounds were stored at 4 degrees C as 10 mM DMSO stocks, and a small subset of compounds was stored as lyophilized dry films. Compound integrity of 470 discrete compounds (Compound Set I) and 1917 combinatorial chemistry-derived compounds (Compound Set II) was evaluated by liquid chromatography/mass spectrometry from the time of acquisition into the library collection and after 3 years of storage. Loss of compound integrity over the 3 years of storage was observed across the 2 subsets tested. Of Compound Set I, 63% of samples retained > 80% purity, whereas 57% of samples from Compound Set II had purity greater than 60%. The stability of the lyophilized samples was superior to the samples stored as DMSO solution. Although storage at 4 degrees C as DMSO solution was adequate for the majority of compounds, the authors observed and quantified the level of degradation within the compound collection. Their study provides general insight into compound storage and selection of library subsets for future lead identification activities.


Assuntos
Técnicas de Química Combinatória/métodos , Preparações Farmacêuticas/análise , Preparações Farmacêuticas/normas , Cromatografia Líquida , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Espectrometria de Massas , Preparações Farmacêuticas/química , Controle de Qualidade , Fatores de Tempo
8.
PLoS One ; 11(5): e0155897, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27191595

RESUMO

Over half of adults are seropositive for JC polyomavirus (JCV), but rare individuals develop progressive multifocal leukoencephalopathy (PML), a demyelinating JCV infection of the central nervous system. Previously, PML was primarily seen in immunosuppressed patients with AIDS or certain cancers, but it has recently emerged as a drug safety issue through its association with diverse immunomodulatory therapies. To better understand the relationship between the JCV life cycle and PML pathology, we studied autopsy brain tissue from a 70-year-old psoriasis patient on the integrin alpha-L inhibitor efalizumab following a ~2 month clinical course of PML. Sequence analysis of lesional brain tissue identified PML-associated viral mutations in regulatory (non-coding control region) DNA, capsid protein VP1, and the regulatory agnoprotein, as well as 9 novel mutations in capsid protein VP2, indicating rampant viral evolution. Nine samples, including three gross PML lesions and normal-appearing adjacent tissues, were characterized by histopathology and subject to quantitative genomic, proteomic, and molecular localization analyses. We observed a striking correlation between the spatial extent of demyelination, axonal destruction, and dispersion of JCV along white matter myelin sheath. Our observations in this case, as well as in a case of PML-like disease in an immunocompromised rhesus macaque, suggest that long-range spread of polyomavirus and axonal destruction in PML might involve extracellular association between virus and the white matter myelin sheath.


Assuntos
Encéfalo/virologia , Vírus JC/patogenicidade , Leucoencefalopatia Multifocal Progressiva/virologia , Bainha de Mielina/metabolismo , Replicação Viral , Idoso , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Feminino , Humanos , Vírus JC/genética , Vírus JC/fisiologia , Macaca mulatta , Masculino , Mutação , Bainha de Mielina/patologia , Bainha de Mielina/virologia , Proteínas Virais de Fusão/genética , Proteínas Virais Reguladoras e Acessórias/genética , Virulência/genética
9.
Drug Metab Dispos ; 30(10): 1094-101, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12228185

RESUMO

Following a single oral or intravenous administration of the R,R(+) and S,S(-) (14)C-pseudoracemate of (+/-)-(1'R*,3R*)-3-phenyl-1-[(1',2',3',4'-tetrahydro-5',6'-methylene-dioxy-1'-naphthalenyl) methyl] pyrrolidine methanesulfonate (ABT-200/I) to dogs, a total of six (R,R[+]) and eight (S,S[-]) metabolites were identified by high-pressure liquid chromatography/mass spectral techniques. Greater than 99% of the dose was eliminated as metabolites indicating that the clearance of I was predominantly metabolic. The catechol was the major excreted metabolite (fecal), whereas the urine and bile predominantly contained metabolites resulting from secondary biotransformation of the catechol via O-methylation, glucuronidation, and sulfation. After a single 12 mg/kg oral dose of racemic I to dogs, the mean area under the plasma curve (AUC(0-24h)) averaged 4.55 micro g. h/ml, with an apparent plasma clearance value of 2.70 l/h. kg. After 14 daily doses, the apparent plasma clearance was 3.5-fold lower (0.78 l/h. kg) and the AUC(0-24h) about 4-fold higher (18.58 micro g. h/ml). Isolation of liver microsomes from these animals indicated that a cytochrome p450 (p450)-metabolite complex (MI complex) was formed in the liver after both single and multiple dosing. The mean concentration of the MI complex 24 h after a single dose averaged 31 pmol/mg of microsomal protein, whereas the amount in the animals given multiple doses of I averaged 163 pmol/mg. There was a positive correlation (R(2) = 0.993) between the plasma AUC for I and the amount of the MI complex found in the liver of each animal. Formation of the MI complex was demonstrated in vitro in control dog liver microsomes, was NADPH-dependent, and was dissociated from p450 with 2-methylbenzimidazole. In vitro preincubation studies indicated that I was a mechanism-based inhibitor and that formation of the complex inhibited catechol formation. These results demonstrate that the liver p450s that metabolize I form an inhibitory MI complex after in vivo administration in dogs. Formation of the complex increases during multiple dosing and inhibits the enzymes from further metabolism of I resulting in nonlinear pharmacokinetics.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Pirrolidinas/farmacocinética , Animais , Bile/enzimologia , Sistema Enzimático do Citocromo P-450/urina , Cães , Fezes/enzimologia , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Dinâmica não Linear , Pirrolidinas/administração & dosagem , Pirrolidinas/química
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