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1.
Acta Neuropathol ; 147(1): 67, 2024 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-38581586

RESUMEN

Transcription factor EB (TFEB) is a master regulator of genes involved in the maintenance of autophagic and lysosomal homeostasis, processes which have been implicated in the pathogenesis of GBA-related and sporadic Parkinson's disease (PD), and dementia with Lewy bodies (DLB). TFEB activation results in its translocation from the cytosol to the nucleus. Here, we investigated TFEB subcellular localization and its relation to intracellular alpha-synuclein (aSyn) accumulation in post-mortem human brain of individuals with either incidental Lewy body disease (iLBD), GBA-related PD/DLB (GBA-PD/DLB) or sporadic PD/DLB (sPD/DLB), compared to control subjects. We analyzed nigral dopaminergic neurons using high-resolution confocal and stimulated emission depletion (STED) microscopy and semi-quantitatively scored the TFEB subcellular localization patterns. We observed reduced nuclear TFEB immunoreactivity in PD/DLB patients compared to controls, both in sporadic and GBA-related cases, as well as in iLBD cases. Nuclear depletion of TFEB was more pronounced in neurons with Ser129-phosphorylated (pSer129) aSyn accumulation in all groups. Importantly, we observed previously-unidentified TFEB-immunopositive perinuclear clusters in human dopaminergic neurons, which localized at the Golgi apparatus. These TFEB clusters were more frequently observed and more severe in iLBD, sPD/DLB and GBA-PD/DLB compared to controls, particularly in pSer129 aSyn-positive neurons, but also in neurons lacking detectable aSyn accumulation. In aSyn-negative cells, cytoplasmic TFEB clusters were more frequently observed in GBA-PD/DLB and iLBD patients, and correlated with reduced GBA enzymatic activity as well as increased Braak LB stage. Altered TFEB distribution was accompanied by a reduction in overall mRNA expression levels of selected TFEB-regulated genes, indicating a possible early dysfunction of lysosomal regulation. Overall, we observed cytoplasmic TFEB retention and accumulation at the Golgi in cells without apparent pSer129 aSyn accumulation in iLBD and PD/DLB patients. This suggests potential TFEB impairment at the early stages of cellular disease and underscores TFEB as a promising therapeutic target for synucleinopathies.


Asunto(s)
Enfermedad por Cuerpos de Lewy , Humanos , alfa-Sinucleína/metabolismo , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/genética , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Encéfalo/patología , Neuronas Dopaminérgicas/metabolismo , Cuerpos de Lewy/patología , Enfermedad por Cuerpos de Lewy/patología
2.
J Cell Physiol ; 237(9): 3578-3586, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35678366

RESUMEN

The insulin signaling pathway controls cell growth and metabolism, thus its deregulation is associated with both cancer and diabetes. Phosphatidylinositol 3-kinase (PI3K) contributes to the cascade of phosphorylation events occurring in the insulin pathway by activating the protein kinase B (PKB/AKT), which phosphorylates several substrates, including those involved in glucose uptake and storage. PI3K inactivating mutations are associated with insulin resistance while activating mutations are identified in human cancers. Here we show that RNAi-induced depletion of the Drosophila PI3K catalytic subunit (Dp110) results in diabetic phenotypes such as hyperglycemia, body size reduction, and decreased glycogen content. Interestingly, we found that hyperglycemia produces chromosome aberrations (CABs) triggered by the accumulation of advanced glycation end-products and reactive oxygen species. Rearing PI3KRNAi flies in a medium supplemented with pyridoxal 5'-phosphate (PLP; the catalytically active form of vitamin B6) rescues DNA damage while, in contrast, treating PI3KRNAi larvae with the PLP inhibitor 4-deoxypyridoxine strongly enhances CAB frequency. Interestingly, PLP supplementation rescues also diabetic phenotypes. Taken together, our results provide a strong link between impaired PI3K activity and genomic instability, a crucial relationship that needs to be monitored not only in diabetes due to impaired insulin signaling but also in cancer therapies based on PI3K inhibitors. In addition, our findings confirm the notion that vitamin B6 is a good natural remedy to counteract insulin resistance and its complications.


Asunto(s)
Daño del ADN , Fosfatidilinositol 3-Quinasa , Vitamina B 6 , Animales , Daño del ADN/efectos de los fármacos , Modelos Animales de Enfermedad , Drosophila/efectos de los fármacos , Drosophila/metabolismo , Glucosa/farmacología , Humanos , Hiperglucemia , Insulina/metabolismo , Resistencia a la Insulina , Fosfatidilinositol 3-Quinasa/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfato de Piridoxal/farmacología , Vitamina B 6/farmacología
3.
Int J Mol Sci ; 22(21)2021 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-34769443

RESUMEN

Several variants of the enzyme pyridox(am)ine 5'-phosphate oxidase (PNPO), responsible for a rare form of vitamin B6-dependent neonatal epileptic encephalopathy known as PNPO deficiency (PNPOD), have been reported. However, only a few of them have been characterised with respect to their structural and functional properties, despite the fact that the knowledge of how variants affect the enzyme may clarify the disease mechanism and improve treatment. Here, we report the characterisation of the catalytic, allosteric and structural properties of recombinantly expressed D33V, R161C, P213S, and E50K variants, among which D33V (present in approximately 10% of affected patients) is one of the more common variants responsible for PNPOD. The D33V and E50K variants have only mildly altered catalytic properties. In particular, the E50K variant, given that it has been found on the same chromosome with other known pathogenic variants, may be considered non-pathogenic. The P213S variant has lower thermal stability and reduced capability to bind the FMN cofactor. The variant involving Arg161 (R161C) largely decreases the affinity for the pyridoxine 5'-phosphate substrate and completely abolishes the allosteric feedback inhibition exerted by the pyridoxal 5'-phosphate product.


Asunto(s)
Encefalopatías Metabólicas/genética , Epilepsia/genética , Hipoxia-Isquemia Encefálica/genética , Mutación , Fosfato de Piridoxal/análogos & derivados , Piridoxaminafosfato Oxidasa/deficiencia , Piridoxaminafosfato Oxidasa/genética , Convulsiones/genética , Vitamina B 6/metabolismo , Encefalopatías Metabólicas/metabolismo , Encefalopatías Metabólicas/patología , Epilepsia/metabolismo , Epilepsia/patología , Humanos , Hipoxia-Isquemia Encefálica/metabolismo , Hipoxia-Isquemia Encefálica/patología , Recién Nacido , Enfermedades Metabólicas/etiología , Enfermedades Metabólicas/metabolismo , Enfermedades Metabólicas/patología , Fosfato de Piridoxal/metabolismo , Piridoxaminafosfato Oxidasa/metabolismo , Convulsiones/metabolismo , Convulsiones/patología , Relación Estructura-Actividad
4.
J Appl Microbiol ; 129(5): 1261-1271, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32445616

RESUMEN

AIMS: To conduct biological investigations and to evaluate the antimicrobial and antioxidant activities of the essential oils (EOs) extracted from Juniperus communis, J. scopulorum and J. horizontalis; to screen their mechanisms of action by conducting the cell membrane permeability assay (CMP); and to determine the possible cytotoxicity of the three EOs against human neuroblastoma cells (SH-SY5Y). METHODS AND RESULTS: The antifungal activity was tested against four phytopathogenic fungi (Monilinia fructicola, Aspergillus niger, Penicillium expansum and Botrytis cinerea). The antibacterial activity was evaluated against two Gram-positive (G+ve) (Bacillus megaterium and Clavibacter michiganensis) and three Gram-negative (G-ve) bacterial strains (Pseudomonas fluorescens, P. syringae pv. phaseolicola and Xanthomonas campestris). Results showed that the three tested EOs have antifungal activity against M. fructicola and P. expansum and effective antibacterial activity against P. syringae pv. phaseolicola and B. megaterium. Moreover, the three EOs were evaluated for their ability to inhibit the growth of SH-SY5Y cells with MTT assay. J. communis EO was the more effective with an IC50 of 53·7 µg ml-1 . The antioxidant capacity of the three EO did not differ as measured by the DPPH assay. CONCLUSIONS: The three tested juniper EOs showed promising antimicrobial and antioxidant activity and cytotoxic effects against human neuroblastoma cell line. SIGNIFICANCE AND IMPACT OF THE STUDY: The outfindings from this research showed promising antimicrobial effects of the three oils against the majority of the tested phytopathogens with a potential to utilize them as natural alternatives to synthetic drugs, the cause of global environmental problems, pathogen resistance and difficulty to control many post-harvest plant diseases.


Asunto(s)
Antiinfecciosos/farmacología , Antioxidantes/farmacología , Juniperus/química , Aceites Volátiles/farmacología , Aceites de Plantas/farmacología , Bacterias/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Hongos/efectos de los fármacos , Humanos , Juniperus/clasificación , Pruebas de Sensibilidad Microbiana , Enfermedades de las Plantas/microbiología
5.
Biochemistry ; 57(51): 6984-6996, 2018 12 26.
Artículo en Inglés | MEDLINE | ID: mdl-30500180

RESUMEN

Serine hydroxymethyltransferase (SHMT) catalyzes the reversible conversion of l-serine and tetrahydrofolate into glycine and 5,10-methylenetetrahydrofolate. This enzyme, which plays a pivotal role in one-carbon metabolism, is involved in cancer metabolic reprogramming and is a recognized target of chemotherapy intervention. In humans, two isoforms of the enzyme exist, which are commonly termed cytosolic SHMT1 and mitochondrial SHMT2. Considerable attention has been paid to the structural, mechanistic, and metabolic features of these isozymes. On the other hand, a detailed comparison of their catalytic and regulatory properties is missing, although this aspect seems to be considerably important, considering that SHMT1 and SHMT2 reside in different cellular compartments, where they play distinct roles in folate metabolism. Here we performed a full kinetic characterization of the serine hydroxymethyltransferase reaction catalyzed by SHMT1 and SHMT2, with a focus on pH dependence and substrate inhibition. Our investigation, which allowed the determination of all kinetic parameters of serine hydroxymethyltransferase forward and backward reactions, uncovered a previously unobserved substrate inhibition by l-serine and highlighted several interesting differences between SHMT1 and SHMT2. In particular, SHMT2 maintains a pronounced tetrahydrofolate substrate inhibition even at the alkaline pH characteristic of the mitochondrial matrix, whereas with SHMT1 this is almost abolished. At this pH, SHMT2 also shows a catalytic efficiency that is much higher than that of SHMT1. These observations suggest that such different properties represent an adaptation of the isoforms to the respective cellular environments and that substrate inhibition may be a form of regulation.


Asunto(s)
Glicina Hidroximetiltransferasa/metabolismo , Citosol/enzimología , Glicina/metabolismo , Glicina Hidroximetiltransferasa/antagonistas & inhibidores , Glicina Hidroximetiltransferasa/química , Humanos , Concentración de Iones de Hidrógeno , Isoenzimas/antagonistas & inhibidores , Isoenzimas/química , Isoenzimas/metabolismo , Cinética , Mitocondrias/enzimología , Modelos Biológicos , Serina/metabolismo , Especificidad por Sustrato , Tetrahidrofolatos/metabolismo
6.
Pol J Vet Sci ; 21(3): 639-642, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30468352

RESUMEN

In the present study on Bubalus bubalis of the Campania Region (Italy) the serum levels of derivatives of reactive oxygen metabolites (d-ROMs), anti-ROM and oxidative stress index (Osi) were evaluated. These data were then related to the seropositive status of the animals against alpha-herpesviruses, precisely Bubaline herpesvirus 1 (BuHV-1) and Bovine herpesvirus 1 (BoHV-1). Clinically healthy Mediterranean buffaloes were selected for this study. The serum samples of these animals were taken, and d-ROMs, anti-ROM and Osi were measured using commercially available tests. The preliminary data demonstrated that animals seropositive to both BuHV-1 and BoHV-1 present more oxidative stress than seronegative animals, as revealed by a significant increase in d-ROMs. Our results provide, for the first time, insight into the reac- tive oxygen species (ROS) modulation induced by the herpesvirus in Bubalus bubalis.


Asunto(s)
Alphaherpesvirinae/inmunología , Búfalos/sangre , Infecciones por Herpesviridae/veterinaria , Animales , Infecciones por Herpesviridae/sangre , Infecciones por Herpesviridae/inmunología , Infecciones por Herpesviridae/metabolismo , Especies Reactivas de Oxígeno , Estudios Seroepidemiológicos
7.
Mol Genet Metab ; 122(1-2): 135-142, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28818555

RESUMEN

BACKGROUND: Pyridoxal-5'-phosphate oxidase (PNPO) deficiency presents as a severe neonatal encephalopathy responsive to pyridoxal-5'-phosphate (PLP) or pyridoxine. Recent studies widened the phenotype of this condition and detected genetic variants on PNPO gene whose pathogenic role and clinical expression remain to be established. OBJECTIVE: This paper aims to characterize the functional effects of the c.347G>A (p.Arg116Gln) mutation in the PNPO gene in order to define its pathogenicity and describe the clinical features of new patients with epilepsy carrying this mutation. METHODS: Arg116Gln protein variant was expressed as recombinant protein. The mutant protein was characterized with respect to structural and kinetic properties, thermal stability, binding constants of cofactor (FMN) and product (PLP). We also reviewed clinical data of 3 new patients carrying the mutation. RESULTS: The Arg116Gln mutation does not alter the overall enzyme structure and only slightly affects its catalytic efficiency; nevertheless, this mutation affects thermal stability of PNPO, reduces its affinity for FMN and impairs transfer of PLP to PLP-dependent enzymes. Three boys with seizure onset between 8months and 3years of age, carrying the Arg116Gln mutation, are described. These three patients exhibited different seizure types associated with interictal EEG abnormalities and slow background activity. Mild/moderate intellectual disability was observed in 2/3 patients. A dramatic therapeutic response to pyridoxine was observed in the only patient who still had active seizures when starting treatment, while in all three patients interictal EEG discharges and background activity improved after pyridoxine treatment was initiated. CONCLUSIONS: The reported data support a pathogenic role of the c.347G>A (p.Arg116Gln) mutation in PNPO deficiency. The later onset of symptoms and the milder epilepsy phenotype of these expand the disease phenotype.


Asunto(s)
Encefalopatías Metabólicas/genética , Encefalopatías Metabólicas/fisiopatología , Hipoxia-Isquemia Encefálica/genética , Hipoxia-Isquemia Encefálica/fisiopatología , Monoéster Fosfórico Hidrolasas/deficiencia , Monoéster Fosfórico Hidrolasas/genética , Piridoxaminafosfato Oxidasa/deficiencia , Convulsiones/genética , Convulsiones/fisiopatología , Preescolar , Femenino , Humanos , Lactante , Masculino , Mutación , Fenotipo , Piridoxaminafosfato Oxidasa/genética , Piridoxina/uso terapéutico , Convulsiones/tratamiento farmacológico
8.
Biochim Biophys Acta Gen Subj ; 1861(1 Pt A): 3474-3489, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27640111

RESUMEN

BACKGROUND: GabR is a transcriptional regulator belonging to the MocR/GabR family, characterized by a N-terminal wHTH DNA-binding domain and a C-terminal effector binding and/or oligomerization domain, structurally homologous to aminotransferases (ATs). In the presence of γ-aminobutyrate (GABA) and pyridoxal 5'-phosphate (PLP), GabR activates the transcription of gabT and gabD genes involved in GABA metabolism. METHODS: Here we report a biochemical and atomic force microscopy characterization of Bacillus subtilis GabR in complex with DNA. Complexes were assembled in vitro to study their stoichiometry, stability and conformation. RESULTS: The fractional occupancy of the GabR cognate site suggests that GabR binds as a dimer with Kd of 10nM. Upon binding GabR bends the DNA by 80° as measured by anomalous electrophoretic mobility. With GABA we observed a decrease in affinity and conformational rearrangements compatible with a less compact nucleo-protein complex but no changes of the DNA bending angle. By employing promoter and GabR mutants we found that basic residues of the positively charged groove on the surface of the AT domain affect DNA affinity. CONCLUSIONS: The present data extend current understanding of the GabR-DNA interaction and the effect of GABA and PLP. A model for the GabR-DNA complex, corroborated by a docking simulation, is proposed. GENERAL SIGNIFICANCE: Characterization of the GabR DNA binding mode highlights the key role of DNA bending and interactions with bases outside the canonical direct repeats, and might be of general relevance for the action mechanism of MocR transcription factors.


Asunto(s)
Bacillus subtilis/metabolismo , Proteínas Bacterianas/metabolismo , ADN Bacteriano/química , ADN Bacteriano/metabolismo , Conformación de Ácido Nucleico , Fosfato de Piridoxal/metabolismo , Factores de Transcripción/metabolismo , Proteínas Bacterianas/química , Secuencia de Bases , Dicroismo Circular , Microscopía de Fuerza Atómica , Modelos Moleculares , Proteínas Mutantes/metabolismo , Regiones Promotoras Genéticas/genética , Unión Proteica , Dominios Proteicos , Secuencias Repetitivas de Ácidos Nucleicos/genética , Alineación de Secuencia , Espectrofotometría Ultravioleta , Electricidad Estática , Ácido gamma-Aminobutírico/metabolismo
9.
Biochim Biophys Acta ; 1854(4): 278-83, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25560296

RESUMEN

L-Threonine aldolases (TAs), a family of enzymes belonging to the fold-type I pyridoxal 5'-phosphate (PLP) dependent enzymes, play a role in catalyzing the reversible cleavage of l-3-hydroxy-α-amino acids to glycine and the corresponding aldehydes. Threonine aldolases have great biotechnological potential for the syntheses of pharmaceutically relevant drug molecules because of their stereospecificity. The pH-dependency of their catalytic activity, affecting reaction intermediates, led us to study the effect of low-pH on Escherichia coli TA (eTA) structure. We report here a low-pH crystal structure of eTA at 2.1 Å resolution, with a non-covalently bound uncleaved l-serine substrate, and a PLP cofactor bound as an internal aldimine. This structure contrasts with other eTA structures obtained at physiological pH that show products or substrates bound as PLP-external aldimines. The non-productive binding at low-pH is due to an unusual substrate serine binding orientation in which the α-amino group and carboxylate group are in the wrong positions (relative to the active site residues) as a result of protonation of the α-amino group of the serine, as well as the active site histidines, His83 and His126. Protonation of these residues prevents the characteristic nucleophilic attack of the α-amino group of substrate serine on C4' of PLP to form the external aldimine. Our study shows that at low pH the change in charge distribution at the active site can result in substrates binding in a non-productive orientation.


Asunto(s)
Escherichia coli/enzimología , Glicina Hidroximetiltransferasa/química , Catálisis , Dominio Catalítico , Cristalografía por Rayos X , Activación Enzimática , Glicina Hidroximetiltransferasa/antagonistas & inhibidores , Concentración de Iones de Hidrógeno , Cinética , Modelos Moleculares , Unión Proteica , Fosfato de Piridoxal/química , Fosfato de Piridoxal/metabolismo , Serina/química , Serina/metabolismo , Treonina/química , Treonina/metabolismo
10.
J Enzyme Inhib Med Chem ; 30(2): 336-40, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24899377

RESUMEN

2-Acetyl-4-((1R,2S,3R)-1,2,3,4-tetrahydroxybutyl)imidazole (THI) is observed as a minor contaminant in caramel food colourings (E 150c). Feeding experiments with rodents have revealed a significant lymphopenic effect that has been linked to the presence of THI in these food colourings. Pyridoxal kinase inhibition by THI has been suggested, but not demonstrated, as a mode of action as it leads to lowered levels of pyridoxal-5'-phosphate, which are known to cause lymphopenia. Recently, THI was also shown to inhibit sphingosine-1-phosphate lyase causing comparable immunosuppressive effects and derivatives of THI are being developed for the treatment of rheumatoid arthritis in humans. Interestingly, sphingosine-1-phosphate lyase activity depends on pyridoxal-5'-phosphate, which in turn is provided by pyridoxal kinase. This report shows that THI does inhibit pyridoxal kinase with competitive and mixed-type non-competitive behaviour towards its two substrates, pyridoxal and ATP, respectively. The corresponding inhibition constants are in the low millimolar range.


Asunto(s)
Colorantes de Alimentos/farmacología , Imidazoles/farmacología , Piridoxal Quinasa/antagonistas & inhibidores , Colorantes de Alimentos/química , Humanos , Imidazoles/química , Modelos Biológicos , Estructura Molecular , Especificidad por Sustrato
11.
Eur J Gynaecol Oncol ; 36(6): 742-5, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26775365

RESUMEN

The authors describe a rare case of primary ovarian fibrosarcoma and the latest trends in diagnosis and therapy. The rarity of this dis-ease and the scarce number of reported cases pose serious problems in differentiating it from other fibrous forms. A 58-year-old woman presented intermittent pelvic pain and a demarcated, mobile, and solid lump in the right adnexa. Diagnostic imaging revealed a solid- cystic inhomogeneous mass occupying the right adnexa and the CA125 level was elevated. The patient underwent total hysterectomy with bilateral salpingo-oophorectomy and infracolic omentectomy. Histological findings with immunomarkers led to the final diagnosis of low-grade malignant mesenchymal neoplasm derived from the ovarian stroma compatible with fibrosarcoma. Twenty-four months follow-up showed no recurrence of disease. Ovarian fibrosarcoma is very uncommon neoplasm with a poor prognosis. Despite the efforts of several authors in reporting morphological, histological, and immunohistochemical features of this neoplasm, nowadays, the diagnosis, treatment, and prognosis are unresolved issues. The present case highlights the important role of immunohistochemistry to define histological type and differential diagnosis. As demonstrated by the authors' experience, they believe that surgery is curative in the early stages with low immunohistochemical positivity for ki67 and that chemotherapy should be reserved in advanced stages with regimens in use for the treatment of sarcomas.


Asunto(s)
Fibrosarcoma/diagnóstico , Neoplasias Ováricas/diagnóstico , Femenino , Fibrosarcoma/patología , Fibrosarcoma/terapia , Humanos , Persona de Mediana Edad , Neoplasias Ováricas/patología , Neoplasias Ováricas/terapia
12.
Acta Neuropathol Commun ; 12(1): 73, 2024 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-38715119

RESUMEN

BACKGROUND: Neuroinflammation and Alzheimer's disease (AD) co-pathology may contribute to disease progression and severity in dementia with Lewy bodies (DLB). This study aims to clarify whether a different pattern of neuroinflammation, such as alteration in microglial and astroglial morphology and distribution, is present in DLB cases with and without AD co-pathology. METHODS: The morphology and load (% area of immunopositivity) of total (Iba1) and reactive microglia (CD68 and HLA-DR), reactive astrocytes (GFAP) and proteinopathies of alpha-synuclein (KM51/pser129), amyloid-beta (6 F/3D) and p-tau (AT8) were assessed in a cohort of mixed DLB + AD (n = 35), pure DLB (n = 15), pure AD (n = 16) and control (n = 11) donors in limbic and neocortical brain regions using immunostaining, quantitative image analysis and confocal microscopy. Regional and group differences were estimated using a linear mixed model analysis. RESULTS: Morphologically, reactive and amoeboid microglia were common in mixed DLB + AD, while homeostatic microglia with a small soma and thin processes were observed in pure DLB cases. A higher density of swollen astrocytes was observed in pure AD cases, but not in mixed DLB + AD or pure DLB cases. Mixed DLB + AD had higher CD68-loads in the amygdala and parahippocampal gyrus than pure DLB cases, but did not differ in astrocytic loads. Pure AD showed higher Iba1-loads in the CA1 and CA2, higher CD68-loads in the CA2 and subiculum, and a higher astrocytic load in the CA1-4 and subiculum than mixed DLB + AD cases. In mixed DLB + AD cases, microglial load associated strongly with amyloid-beta (Iba1, CD68 and HLA-DR), and p-tau (CD68 and HLA-DR), and minimally with alpha-synuclein load (CD68). In addition, the highest microglial activity was found in the amygdala and CA2, and astroglial load in the CA4. Confocal microscopy demonstrated co-localization of large amoeboid microglia with neuritic and classic-cored plaques of amyloid-beta and p-tau in mixed DLB + AD cases. CONCLUSIONS: In conclusion, microglial activation in DLB was largely associated with AD co-pathology, while astrocytic response in DLB was not. In addition, microglial activity was high in limbic regions, with prevalent AD pathology. Our study provides novel insights into the molecular neuropathology of DLB, highlighting the importance of microglial activation in mixed DLB + AD.


Asunto(s)
Enfermedad de Alzheimer , Astrocitos , Enfermedad por Cuerpos de Lewy , Microglía , Enfermedades Neuroinflamatorias , Humanos , Enfermedad por Cuerpos de Lewy/patología , Enfermedad por Cuerpos de Lewy/metabolismo , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/metabolismo , Femenino , Masculino , Anciano , Anciano de 80 o más Años , Enfermedades Neuroinflamatorias/patología , Enfermedades Neuroinflamatorias/metabolismo , Microglía/patología , Microglía/metabolismo , Astrocitos/patología , Astrocitos/metabolismo , alfa-Sinucleína/metabolismo , Proteínas tau/metabolismo , Antígenos CD/metabolismo , Péptidos beta-Amiloides/metabolismo , Persona de Mediana Edad , Antígenos de Diferenciación Mielomonocítica/metabolismo , Encéfalo/patología , Encéfalo/metabolismo , Molécula CD68
14.
Arch Biochem Biophys ; 529(2): 55-65, 2013 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-23219598

RESUMEN

Cyclosporin A, a cyclic peptide produced by the fungus Tolypocladium inflatum, is a widely employed immunosuppressant drug. Its biosynthesis is strictly dependent on the action of the pyridoxal 5'-phosphate-dependent enzyme alanine racemase, which produces the d-alanine incorporated in the cyclic peptide. This enzyme has a different fold with respect to bacterial alanine racemases. The interest elicited by T. inflatum alanine racemase not only relies on its biotechnological relevance, but also on its evolutionary and structural similarity to the promiscuous enzymes serine hydroxymethyltransferase and threonine aldolase. The three enzymes represent a model of divergent evolution from an ancestral enzyme that was able to catalyse all the reactions of the modern enzymes. A protocol to express and purify with high yield recombinant T. inflatum alanine racemase was developed. The catalytic properties of the enzyme were characterized. Similarly to serine hydroxymethyltransferase and threonine aldolase, T. inflatum alanine racemase was able to catalyse retroaldol cleavage and transamination reactions. This observation corroborates the hypothesis of the common evolutionary origin of these enzymes. A three-dimensional model of T. inflatum alanine racemase was constructed on the basis of threonine aldolase crystal structure. The model helped rationalise the experimental data and explain the catalytic properties of the enzymes.


Asunto(s)
Alanina Racemasa/química , Alanina Racemasa/metabolismo , Ascomicetos/enzimología , Ciclosporina/metabolismo , Modelos Químicos , Modelos Moleculares , Alanina Racemasa/ultraestructura , Secuencia de Aminoácidos , Catálisis , Simulación por Computador , Activación Enzimática , Datos de Secuencia Molecular
15.
Int J Immunopathol Pharmacol ; 26(1): 117-25, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23527714

RESUMEN

Regulatory T cells (Tregs) are considered to be key immunomodulatory cells of the immune system and are increased in chronic lymphocytic leukemia (CLL). Rai stage 0 identifies patients with early stage CLL for which there is no effective intervention at the present time and a "wait and see" policy is usually adopted. Some biological and clinical studies have reported that green tea constituents, such as epigallocatechin-gallate (EGCG), have antitumor effects on hematologic malignancies including CLL. We report data on a clinical trial in which green tea extracts were given orally to 12 patients with stage 0 CLL and 12 healthy subjects. Ten patients and 10 controls completed the 6-month scheduled therapy. Two patients and 2 controls stopped therapy within 1 month because of tachycardia and epigastralgia. Eight out 10 evaluable patients (80 percent) showed a reduction of lymphocytosis and absolute number of circulating Tregs, as well. One patient (10 percent) had a stabilization of lymphocytosis and a reduction of Tregs, and 1 patient (10 percent) showed an increase of both lymphocytosis and Tregs. Only the non-responding patient progressed after 5 months from the end of green tea administration and chemotherapy was given. Interestingly, both IL-10 and TGF-beta serum levels declined throughout the green tea intake period, in both patients and controls. These data seem to indicate that green tea is able to modulate circulating Tregs in CLL patients with early stage of the disease. This can result in the control of lymphocytosis as well as in the prevention of disease progression.


Asunto(s)
Camellia sinensis , Factores Inmunológicos/farmacología , Leucemia Linfocítica Crónica de Células B/inmunología , Extractos Vegetales/farmacología , Linfocitos T Reguladores/efectos de los fármacos , Adulto , Anciano , Anciano de 80 o más Años , Recuento de Linfocito CD4 , Cafeína/análisis , Catequina/análogos & derivados , Catequina/análisis , Femenino , Humanos , Factores Inmunológicos/química , Interleucina-10/sangre , Masculino , Persona de Mediana Edad , Extractos Vegetales/química , Linfocitos T Reguladores/inmunología , Factor de Crecimiento Transformador beta/sangre
16.
J Endocrinol Invest ; 36(10): 903-12, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23723078

RESUMEN

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is a rare autosomal recessive disease caused by mutations of the AutoImmune REgulator gene. The clinical spectrum of the disease encompasses several autoimmune endocrine and non-endocrine manifestations, which may lead to acute metabolic alterations and eventually life-threatening events. The clinical diagnosis is defined by the presence of at least two components of the classic triad including chronic mucocoutaneous candidiasis (CMC), chronic hypoparathyroidism (CH), Addison's disease (AD). Other common features of the disease are hypergonadotropic hypogonadism, alopecia, vitiligo, autoimmune hepatitis, Type 1 diabetes, gastrointestinal dysfunction. APECED usually begins in childhood. CMC is the first manifestation to appear, usually before the age of 5 yr, followed by CH and then by AD. The clinical phenotype may evolve over several years and many components of the disease may not appear until the 4th or 5th decade of life. The phenotypical expression of the syndrome shows a wide variability even between siblings with the same genotype. In view of this heterogeneity, an early diagnosis of APECED can be very challenging often leading to a considerable diagnostic delay. Therefore, clinicians should be aware that the presence of even a minor component of APECED in children should prompt a careful investigation for other signs and symptoms of the disease, thus allowing an early diagnosis and prevention of severe and life-threatening events. Aim of this review is to focus on clinical presentation, diagnosis and management of the major components of APECED in children particularly focusing on endocrine features of the disease.


Asunto(s)
Enfermedad de Addison/patología , Candidiasis Mucocutánea Crónica/patología , Hipoparatiroidismo/patología , Poliendocrinopatías Autoinmunes/patología , Humanos , Pronóstico
17.
Nat Commun ; 14(1): 2057, 2023 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-37045813

RESUMEN

Mutations in glucocerebrosidase cause the lysosomal storage disorder Gaucher's disease and are the most common risk factor for Parkinson's disease. Therapies to restore the enzyme's function in the brain hold great promise for treating the neurological implications. Thus, we developed blood-brain barrier penetrant therapeutic molecules by fusing transferrin receptor-binding moieties to ß-glucocerebrosidase (referred to as GCase-BS). We demonstrate that these fusion proteins show significantly increased uptake and lysosomal efficiency compared to the enzyme alone. In a cellular disease model, GCase-BS rapidly rescues the lysosomal proteome and lipid accumulations beyond known substrates. In a mouse disease model, intravenous injection of GCase-BS leads to a sustained reduction of glucosylsphingosine and can lower neurofilament-light chain plasma levels. Collectively, these findings demonstrate the potential of GCase-BS for treating GBA1-associated lysosomal dysfunction, provide insight into candidate biomarkers, and may ultimately open a promising treatment paradigm for lysosomal storage diseases extending beyond the central nervous system.


Asunto(s)
Enfermedad de Gaucher , Enfermedad de Parkinson , Animales , Ratones , Enfermedad de Gaucher/genética , Glucosilceramidasa/genética , Glucosilceramidasa/metabolismo , Encéfalo/metabolismo , Neuronas/metabolismo , Enfermedad de Parkinson/metabolismo , Lisosomas/metabolismo , Mutación , alfa-Sinucleína/metabolismo
18.
Am J Med Genet A ; 158A(4): 856-60, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22419608

RESUMEN

Noonan-like syndrome with loose anagen hair (NS/LAH; OMIM 607721), recently related to the invariant c.4A>G missense change in SHOC2, is characterized by features reminiscent of Noonan syndrome. Ectodermal involvement, short stature associated with growth hormone (GH) deficiency (GHD), and cognitive deficits are common features. We report on a patient with molecularly confirmed NS/LAH exhibiting severe short stature associated with GH insensitivity (GHI), and chronic complex tics, a neurological feature never described before in this syndrome. IGF1 generation test revealed only a blunted increase in IGF1 after exogenous GH treatment, revealing mild GH insensitivity associated with proper STAT5 activation. Most common causes of secondary tics in childhood were excluded.


Asunto(s)
Síndrome de Laron/genética , Síndrome del Cabello Anágeno Suelto/genética , Síndrome de Noonan/genética , Tics/genética , Niño , Femenino , Humanos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Factor de Transcripción STAT5/metabolismo , Tics/complicaciones
19.
Eur J Gynaecol Oncol ; 33(5): 467-71, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23185789

RESUMEN

OBJECTIVE: To evaluate the effects of infection in multiple types of high-risk human papilloma virus (HPV) in cervical preneoplastic lesions in patients undergoing colposcopy following a diagnosis of atypical squamous cells of unknown significance (ASCUS) and low-grade squamous intraepithelial (LSIL) cytology. MATERIALS AND METHODS: Between 2009 and 2010, 2,500 patients were recruited with a mean age of 35 +/- 5 years. Screening for cervical cancer was performed and in case of ASCUS and LSIL the patients underwent colposcopy. The tests for the detection and typing of viral DNA (HPV - DNA test) were performed on cervical swab with real-time PCR amplification. RESULTS: The prevalence of infection was 70% (1579/2256) in the patients recruited. In relation to the degree of preneoplastic lesions some high-risk HPV viral genotypes were identified: HPV 16 (319/1466), HPV 18 (164/1466), HPV 45 (76/1466), HPV 31 (215/1466), HPV 52 (145/1466), HPV 58 (55/1466) HPV 56 (79/1466), HPV 51 (110/1466), HPV 6(138/1466), HPV 11 (88/1466), HPV 42 (34/1466), HPV 53 (43/1466). In case of high-grade lesions of CIN (CIN2 and CIN3) a greater HPV co-infection was detected and in particular the association from 16 to 18 (70%), 16-33 (18%) and 16 to 52 (12%). CONCLUSIONS: Infection caused by the simultaneous presence of multiple HPV genotypes appears to be associated with a significantly increased risk of high-grade lesions of CIN or invasive cancer than the presence of single viral infections. The infection with multiple HPV types is a significant risk factor for high-grade lesions of CIN in women undergoing colposcopy for ASCUS cytology/LSIL. The use of real-time PCR has shown the ability not only to identify the different types of HPV, but also to monitor quantitatively the same over time, and during the study phase, to evaluate the sensitivity and specificity of the method in comparison with other techniques.


Asunto(s)
Papillomaviridae/aislamiento & purificación , Lesiones Precancerosas/virología , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Neoplasias del Cuello Uterino/virología , Adulto , Carcinoma de Células Escamosas/virología , Femenino , Humanos , Riesgo , Displasia del Cuello del Útero/virología
20.
J Anim Physiol Anim Nutr (Berl) ; 96(1): 130-6, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21429044

RESUMEN

To evaluate the effect of mannan-oligosaccharides (MOS) on in vivo performance, nutrient digestibility, fermentation characteristics and caecal microbial populations of rabbits, 144 thirty-five days old hybrid Hyla were equally divided into three groups, one of which was fed the same diet without additives (control group), one with antibiotics (colistin sulphate, 144 mg/kg; tylosin, 100 mg/kg; oxytetracyclin, 1000 mg/kg) and one with MOS (1 g/kg of diet). Mortality rate, live weight, feed intake and feed conversion ratio were recorded up to 62 days of age. At 60 days nutrient digestibility was measured by acid insoluble ash method. The caecal content of 10 rabbits per group was collected at 62 days and analysed for volatile fatty acids production, ammonia content and microbial count. Rabbits from the control group had a significantly (p < 0.01) lower body weight at 62 days (1638.9 g vs. 1779.4 g and 1862.5 g, respectively for the control, MOS and antibiotic groups) while the antibiotic group showed a higher (p < 0.05) feed intake than the control group (127.9 g/day vs. 109.3 g/day). Rabbits from the MOS group had a higher apparent digestibility of cellulose (34.27% vs. 29.61% and 27.49%, respectively for the MOS, control and antibiotic groups) and, as a consequence a higher level of acetate in the caecal content (39.93 mmol/l vs. 34.21 mmol/l and 23.09 mmol/l, respectively for the MOS, control and antibiotic groups). Caecal microflora of the MOS group rabbits also had a higher fermentative activity in respect of protein source, as demonstrated by the higher productions of branched chain fatty acids. MOS and antibiotics significantly reduced the colonies of Coliformis (2.32 vs. 3.20 vs. 2.40 logCFU/g, respectively for the MOS, control and antibiotic groups, p < 0.01). Mannan-oligosaccharides at 1 g/kg of diet can be used as an alternative to antibiotics during the rabbit's growth period.


Asunto(s)
Ciego/química , Digestión/efectos de los fármacos , Contenido Digestivo/química , Mananos/farmacología , Conejos/crecimiento & desarrollo , Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Femenino , Masculino , Mananos/química , Conejos/fisiología , Aumento de Peso
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