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1.
J Transl Med ; 22(1): 548, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849800

RESUMO

BACKGROUND: Despite significant advancements in treatment strategies, multiple myeloma remains incurable. Additionally, there is a distinct lack of reliable biomarkers that can guide initial treatment decisions and help determine suitable replacement or adjuvant therapies when relapse ensues due to acquired drug resistance. METHODS: To define specific proteins and pathways involved in the progression of monoclonal gammopathy of undetermined significance (MGUS) to multiple myeloma (MM), we have applied super-SILAC quantitative proteomic analysis to CD138 + plasma cells from 9 individuals with MGUS and 37 with MM. RESULTS: Unsupervised hierarchical clustering defined three groups: MGUS, MM, and MM with an MGUS-like proteome profile (ML) that may represent a group that has recently transformed to MM. Statistical analysis identified 866 differentially expressed proteins between MM and MGUS, and 189 between MM and ML, 177 of which were common between MGUS and ML. Progression from MGUS to MM is accompanied by upregulated EIF2 signaling, DNA repair, and proteins involved in translational quality control, whereas integrin- and actin cytoskeletal signaling and cell surface markers are downregulated. CONCLUSION: Compared to the premalignant plasma cells in MGUS, malignant MM cells apparently have mobilized several pathways that collectively contribute to ensure translational fidelity and to avoid proteotoxic stress, especially in the ER. The overall reduced expression of immunoglobulins and surface antigens contribute to this and may additionally mediate evasion from recognition by the immune apparatus. Our analyses identified a range of novel biomarkers with potential prognostic and therapeutic value, which will undergo further evaluation to determine their clinical significance.


Assuntos
Progressão da Doença , Gamopatia Monoclonal de Significância Indeterminada , Mieloma Múltiplo , Humanos , Mieloma Múltiplo/imunologia , Mieloma Múltiplo/patologia , Gamopatia Monoclonal de Significância Indeterminada/imunologia , Proteômica , Masculino , Feminino , Biossíntese de Proteínas , Pessoa de Meia-Idade , Idoso , Análise por Conglomerados , Plasmócitos/imunologia , Plasmócitos/patologia , Plasmócitos/metabolismo , Transdução de Sinais , Proteoma/metabolismo , Controle de Qualidade
2.
Plant Cell Physiol ; 64(6): 583-603, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-36852859

RESUMO

The chloroplast signal recognition particle (CpSRP) receptor (CpFTSY) is a component of the CpSRP pathway that post-translationally targets light-harvesting complex proteins (LHCPs) to the thylakoid membranes in plants and green algae containing chloroplasts derived from primary endosymbiosis. In plants, CpFTSY also plays a major role in the co-translational incorporation of chloroplast-encoded subunits of photosynthetic complexes into the thylakoids. This role has not been demonstrated in green algae. So far, its function in organisms with chloroplasts derived from secondary endosymbiotic events has not been elucidated. Here, we report the generation and characterization of mutants lacking CpFTSY in the diatom Phaeodactylum tricornutum. We found that this protein is not involved in inserting LHCPs into thylakoid membranes, indicating that the post-translational part of the CpSRP pathway is not active in this group of microalgae. The lack of CpFTSY caused an increased level of photoprotection, low electron transport rates, inefficient repair of photosystem II (PSII), reduced growth, a strong decline in the PSI subunit PsaC and upregulation of proteins that might compensate for a non-functional co-translational CpSRP pathway during light stress conditions. The phenotype was highly similar to the one described for diatoms lacking another component of the co-translational CpSRP pathway, the CpSRP54 protein. However, in contrast to cpsrp54 mutants, only one thylakoid membrane protein, PetD of the Cytb6f complex, was downregulated in cpftsy. Our results point to a minor role for CpFTSY in the co-translational CpSRP pathway, suggesting that other mechanisms may partially compensate for the effect of a disrupted CpSRP pathway.


Assuntos
Diatomáceas , Diatomáceas/genética , Diatomáceas/metabolismo , Proteínas de Cloroplastos/metabolismo , Tilacoides/metabolismo , Cloroplastos/metabolismo , Complexo de Proteína do Fotossistema II/genética , Complexo de Proteína do Fotossistema II/metabolismo , Complexos de Proteínas Captadores de Luz/metabolismo
3.
Proteomics ; 22(10): e2100223, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35170848

RESUMO

MALDI MS imaging (MSI) is a powerful analytical tool for spatial peptide detection in heterogeneous tissues. Proper sample preparation is crucial to achieve high quality, reproducible measurements. Here we developed an optimized protocol for spatially resolved proteolytic peptide detection with MALDI time-of-flight MSI of fresh frozen prostate tissue sections. The parameters tested included four different tissue washes, four methods of protein denaturation, four methods of trypsin digestion (different trypsin densities, sprayers, and incubation times), and five matrix deposition methods (different sprayers, settings, and matrix concentrations). Evaluation criteria were the number of detected and excluded peaks, percentage of high mass peaks, signal-to-noise ratio, spatial localization, and average intensities of identified peptides, all of which were integrated into a weighted quality evaluation scoring system. Based on these scores, the optimized protocol included an ice-cold EtOH+H2 O wash, a 5 min heating step at 95°C, tryptic digestion incubated for 17h at 37°C and CHCA matrix deposited at a final amount of 1.8 µg/mm2 . Including a heat-induced protein denaturation step after tissue wash is a new methodological approach that could be useful also for other tissue types. This optimized protocol for spatial peptide detection using MALDI MSI facilitates future biomarker discovery in prostate cancer and may be useful in studies of other tissue types.


Assuntos
Peptídeos , Próstata , Humanos , Masculino , Próstata/metabolismo , Proteínas , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Tripsina/metabolismo
4.
Plant J ; 106(1): 113-132, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33372269

RESUMO

The chloroplast signal recognition particle 54 kDa (CpSRP54) protein is a member of the CpSRP pathway known to target proteins to thylakoid membranes in plants and green algae. Loss of CpSRP54 in the marine diatom Phaeodactylum tricornutum lowers the accumulation of a selection of chloroplast-encoded subunits of photosynthetic complexes, indicating a role in the co-translational part of the CpSRP pathway. In contrast to plants and green algae, absence of CpSRP54 does not have a negative effect on the content of light-harvesting antenna complex proteins and pigments in P. tricornutum, indicating that the diatom CpSRP54 protein has not evolved to function in the post-translational part of the CpSRP pathway. Cpsrp54 KO mutants display altered photophysiological responses, with a stronger induction of photoprotective mechanisms and lower growth rates compared to wild type when exposed to increased light intensities. Nonetheless, their phenotype is relatively mild, thanks to the activation of mechanisms alleviating the loss of CpSRP54, involving upregulation of chaperones. We conclude that plants, green algae, and diatoms have evolved differences in the pathways for co-translational and post-translational insertion of proteins into the thylakoid membranes.


Assuntos
Proteínas de Cloroplastos/metabolismo , Cloroplastos/metabolismo , Diatomáceas/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Clorófitas/genética , Clorófitas/metabolismo , Proteínas de Cloroplastos/genética , Cloroplastos/genética , Diatomáceas/genética , Edição de Genes , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Tilacoides/genética , Tilacoides/metabolismo
5.
FASEB J ; 35(7): e21714, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34118107

RESUMO

We tested the hypothesis that cancer cachexia progression would induce oxidative post-translational modifications (Ox-PTMs) associated with skeletal muscle wasting, with different responses in muscles with the prevalence of glycolytic and oxidative fibers. We used cysteine-specific isotopic coded affinity tags (OxICAT) and gel-free mass spectrometry analysis to investigate the cysteine Ox-PTMs profile in the proteome of both plantaris (glycolytic) and soleus (oxidative) muscles in tumor-bearing and control rats. Histological analysis revealed muscle atrophy in type II fibers in plantaris muscle, with no changes in plantaris type I fibers and no differences in both soleus type I and II fibers in tumor-bearing rats when compared to healthy controls. Tumor progression altered the Ox-PTMs profile in both plantaris and soleus. However, pathway analysis including the differentially oxidized proteins revealed tricarboxylic acid cycle and oxidative phosphorylation as main affected pathways in plantaris muscle from tumor-bearing rats, while the same analysis did not show main metabolic pathways affected in the soleus muscle. In addition, cancer progression affected several metabolic parameters such as ATP levels and markers of oxidative stress associated with muscle atrophy in plantaris muscle, but not in soleus. However, isolated soleus from tumor-bearing rats had a reduced force production capacity when compared to controls. These novel findings demonstrate that tumor-bearing rats have severe muscle atrophy exclusively in glycolytic fibers. Cancer progression is associated with cysteine Ox-PTMs in the skeletal muscle, but these modifications affect different pathways in a glycolytic muscle compared to an oxidative muscle, indicating that intrinsic muscle oxidative capacity determines the response to cancer cachectic effects.


Assuntos
Músculo Esquelético/patologia , Atrofia Muscular/patologia , Neoplasias/patologia , Estresse Oxidativo/fisiologia , Animais , Caquexia/patologia , Progressão da Doença , Glicólise/fisiologia , Masculino , Fibras Musculares de Contração Rápida/patologia , Fibras Musculares de Contração Lenta/patologia , Oxirredução , Fosforilação Oxidativa , Ratos , Ratos Wistar
6.
J Transl Med ; 19(1): 287, 2021 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-34217309

RESUMO

BACKGROUND: Reversible enzymatic methylation of mammalian mRNA is widespread and serves crucial regulatory functions, but little is known to what degree chemical alkylators mediate overlapping modifications and whether cells distinguish aberrant from canonical methylations. METHODS: Here we use quantitative mass spectrometry to determine the fate of chemically induced methylbases in the mRNA of human cells. Concomitant alteration in the mRNA binding proteome was analyzed by SILAC mass spectrometry. RESULTS: MMS induced prominent direct mRNA methylations that were chemically identical to endogenous methylbases. Transient loss of 40S ribosomal proteins from isolated mRNA suggests that aberrant methylbases mediate arrested translational initiation and potentially also no-go decay of the affected mRNA. Four proteins (ASCC3, YTHDC2, TRIM25 and GEMIN5) displayed increased mRNA binding after MMS treatment. ASCC3 is a binding partner of the DNA/RNA demethylase ALKBH3 and was recently shown to promote disassembly of collided ribosomes as part of the ribosome quality control (RQC) trigger complex. We find that ASCC3-deficient cells display delayed removal of MMS-induced 1-methyladenosine (m1A) and 3-methylcytosine (m3C) from mRNA and impaired formation of MMS-induced P-bodies. CONCLUSIONS: Our findings conform to a model in which ASCC3-mediated disassembly of collided ribosomes allows demethylation of aberrant m1A and m3C by ALKBH3. Our findings constitute first evidence of selective sanitation of aberrant mRNA methylbases over their endogenous counterparts and warrant further studies on RNA-mediated effects of chemical alkylators commonly used in the clinic.


Assuntos
Citosina , Ribossomos , Adenosina/análogos & derivados , Homólogo AlkB 3 da Dioxigenase Dependente de alfa-Cetoglutarato , Animais , Citosina/análogos & derivados , DNA Helicases , Humanos , RNA Helicases , RNA Mensageiro/genética , Fatores de Transcrição , Proteínas com Motivo Tripartido , Ubiquitina-Proteína Ligases
7.
Int J Mol Sci ; 22(10)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069552

RESUMO

There is little in vitro data available on long-term effects of TiO2 exposure. Such data are important for improving the understanding of underlying mechanisms of adverse health effects of TiO2. Here, we exposed pulmonary epithelial cells to two doses (0.96 and 1.92 µg/cm2) of TiO2 for 13 weeks and effects on cell cycle and cell death mechanisms, i.e., apoptosis and autophagy were determined after 4, 8 and 13 weeks of exposure. Changes in telomere length, cellular protein levels and lipid classes were also analyzed at 13 weeks of exposure. We observed that the TiO2 exposure increased the fraction of cells in G1-phase and reduced the fraction of cells in G2-phase, which was accompanied by an increase in the fraction of late apoptotic/necrotic cells. This corresponded with an induced expression of key apoptotic proteins i.e., BAD and BAX, and an accumulation of several lipid classes involved in cellular stress and apoptosis. These findings were further supported by quantitative proteome profiling data showing an increase in proteins involved in cell stress and genomic maintenance pathways following TiO2 exposure. Altogether, we suggest that cell stress response and cell death pathways may be important molecular events in long-term health effects of TiO2.


Assuntos
Células Epiteliais Alveolares/metabolismo , Titânio/efeitos adversos , Células Epiteliais Alveolares/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Divisão Celular , Linhagem Celular , Células Epiteliais/metabolismo , Expressão Gênica/genética , Perfilação da Expressão Gênica/métodos , Humanos , Pulmão/metabolismo , Nanopartículas Metálicas/efeitos adversos , Nanopartículas/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Proteômica/métodos , Alvéolos Pulmonares/efeitos dos fármacos , Alvéolos Pulmonares/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Titânio/metabolismo , Transcriptoma/genética
8.
J Transl Med ; 18(1): 159, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32264925

RESUMO

BACKGROUND: HDAC inhibitors (HDACi) belong to a new group of chemotherapeutics that are increasingly used in the treatment of lymphocyte-derived malignancies, but their mechanisms of action remain poorly understood. Here we aimed to identify novel protein targets of HDACi in B- and T-lymphoma cell lines and to verify selected candidates across several mammalian cell lines. METHODS: Jurkat T- and SUDHL5 B-lymphocytes were treated with the HDACi SAHA (vorinostat) prior to SILAC-based quantitative proteome analysis. Selected differentially expressed proteins were verified by targeted mass spectrometry, RT-PCR and western analysis in multiple mammalian cell lines. Genomic uracil was quantified by LC-MS/MS, cell cycle distribution analyzed by flow cytometry and class switch recombination monitored by FACS in murine CH12F3 cells. RESULTS: SAHA treatment resulted in differential expression of 125 and 89 proteins in Jurkat and SUDHL5, respectively, of which 19 were commonly affected. Among these were several oncoproteins and tumor suppressors previously not reported to be affected by HDACi. Several key enzymes determining the cellular dUTP/dTTP ratio were downregulated and in both cell lines we found robust depletion of UNG2, the major glycosylase in genomic uracil sanitation. UNG2 depletion was accompanied by hyperacetylation and mediated by increased proteasomal degradation independent of cell cycle stage. UNG2 degradation appeared to be ubiquitous and was observed across several mammalian cell lines of different origin and with several HDACis. Loss of UNG2 was accompanied by 30-40% increase in genomic uracil in freely cycling HEK cells and reduced immunoglobulin class-switch recombination in murine CH12F3 cells. CONCLUSION: We describe several oncoproteins and tumor suppressors previously not reported to be affected by HDACi in previous transcriptome analyses, underscoring the importance of proteome analysis to identify cellular effectors of HDACi treatment. The apparently ubiquitous depletion of UNG2 and PCLAF establishes DNA base excision repair and translesion synthesis as novel pathways affected by HDACi treatment. Dysregulated genomic uracil homeostasis may aid interpretation of HDACi effects in cancer cells and further advance studies on this class of inhibitors in the treatment of APOBEC-expressing tumors, autoimmune disease and HIV-1.


Assuntos
Inibidores de Histona Desacetilases , Uracila , Animais , Linhagem Celular , Cromatografia Líquida , Genômica , Inibidores de Histona Desacetilases/farmacologia , Camundongos , Proteínas Oncogênicas , Linfócitos T , Espectrometria de Massas em Tandem , Uracila/farmacologia
9.
J Proteome Res ; 18(3): 1237-1247, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30707844

RESUMO

Extracellular vesicles are emerging as biomarkers in breast cancer. Our recent report suggested that an intracellular granular staining pattern of the extracellular matrix protein nephronectin (NPNT) in breast tumor sections correlated with a poor prognosis. Furthermore, the results showed that NPNT is localized in extracellular vesicles derived from mouse breast cancer cells. In this study, we performed proteomic analysis that revealed that several proteins, including tumor-promoting molecules, are differentially expressed in the cargo of small extracellular vesicles (sEVs) derived from NPNT-expressing mouse breast cancer cells. We also identified three different forms of NPNT at 80, 60, and 20 kDa. We report that the native form of NPNT at 60 kDa becomes further glycosylated and is detected as the 80 kDa NPNT, which may be processed by matrix metalloproteinases to a shorter form of around 20 kDa, which has not previously been described. Although both 80 and 20 kDa NPNT are detected in sEVs derived from breast cancer cells, the 20 kDa form of NPNT is concentrated in sEVs. In summary, we show that a novel truncated form of NPNT is found in sEVs derived from breast cancer cells.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Proteínas da Matriz Extracelular/genética , Proteômica , Animais , Neoplasias da Mama/patologia , Modelos Animais de Doenças , Vesículas Extracelulares/genética , Vesículas Extracelulares/patologia , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Glicosilação , Humanos , Camundongos , Isoformas de Proteínas/genética
10.
Nucleic Acids Res ; 45(14): 8291-8301, 2017 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-28575236

RESUMO

Base lesions in DNA can stall the replication machinery or induce mutations if bypassed. Consequently, lesions must be repaired before replication or in a post-replicative process to maintain genomic stability. Base excision repair (BER) is the main pathway for repair of base lesions and is known to be associated with DNA replication, but how BER is organized during replication is unclear. Here we coupled the iPOND (isolation of proteins on nascent DNA) technique with targeted mass-spectrometry analysis, which enabled us to detect all proteins required for BER on nascent DNA and to monitor their spatiotemporal orchestration at replication forks. We demonstrate that XRCC1 and other BER/single-strand break repair (SSBR) proteins are enriched in replisomes in unstressed cells, supporting a cellular capacity of post-replicative BER/SSBR. Importantly, we identify for the first time the DNA glycosylases MYH, UNG2, MPG, NTH1, NEIL1, 2 and 3 on nascent DNA. Our findings suggest that a broad spectrum of DNA base lesions are recognized and repaired by BER in a post-replicative process.


Assuntos
Quebras de DNA de Cadeia Simples , Enzimas Reparadoras do DNA/metabolismo , Reparo do DNA , Replicação do DNA , DNA/genética , Linhagem Celular Tumoral , DNA/metabolismo , DNA Glicosilases/metabolismo , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Proteínas de Ligação a DNA/metabolismo , Desoxirribonuclease (Dímero de Pirimidina)/metabolismo , Células HEK293 , Células HeLa , Humanos , Immunoblotting , Espectrometria de Massas/métodos , N-Glicosil Hidrolases/metabolismo , Transdução de Sinais/genética , Fatores de Tempo , Proteína 1 Complementadora Cruzada de Reparo de Raio-X
11.
BMC Public Health ; 19(1): 1039, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375074

RESUMO

BACKGROUND: Interventions in India to improve menstrual health and hygiene management (MHHM) have been implemented at the national, state, district and school level. However, evaluations of these interventions have been scarce. The objective of the study was to determine if a social and behavioral change communication (SBCC) intervention (GARIMA) had a relationship with knowledge, attitudes, interpersonal communication, restrictions and MHHM using a comparison group post-test only design among 2206 adolescent girls. METHODS: Intervention villages and adolescent girls were selected through stratified random sampling based on where GARIMA was implemented. Villages and adolescent girls in comparison villages were matched socio-demographically to intervention villages and adolescent girls. Multi-level logistic regressions assessed the relationship between the encoded exposure, mediators and MHHM. RESULTS: The results showed that the encoded exposure predicted all behaviors corresponding to MHHM. Additionally, adolescent girls in the high encoded exposure group had significantly higher knowledge about puberty and reproductive parts (AOR: 2.03 (95% CI: 1.31 - 3.15)), positive attitudes towards gender (AOR: 1.48 (95% CI: 1.02 - 2.16)) and higher levels of some discussion and dialogue (AOR: 1.41 (95% CI: 1.04 - 1.92)). CONCLUSIONS: Future programs should use SBCC to improve MHHM behavior but involve families, peers and community members to a greater extent in order to improve attitudes towards menstruation, attitudes towards restrictions, attitudes towards absorbent use and reduce restrictions within the community.


Assuntos
Comunicação , Promoção da Saúde/métodos , Higiene/normas , Menstruação/psicologia , Mudança Social , Adolescente , Criança , Estudos Transversais , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Índia , Avaliação de Programas e Projetos de Saúde , Inquéritos e Questionários
12.
Anal Biochem ; 523: 10-16, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28167071

RESUMO

The Multiplexed Inhibitor Bead (MIB) assay is a previously published quantitative proteomic MS-based approach to study cellular kinomes. A rather extensive procedure, need for multiple custom-made kinase inhibitors and an inability to re-use the MIB-columns, has limited its applicability. Here we present a modified MIB assay in which elution of bound proteins is facilitated by on-column trypsinization. We tested the modified MIB assay by analyzing extract from three human cancer cell lines treated with the cytotoxic drugs cisplatin or docetaxel. Using only three immobilized kinase inhibitors, we were able to detect about 6000 proteins, including ∼40% of the kinome, as well as other signaling, metabolic and structural proteins. The method is reproducible and the MIB-columns are re-usable without loss of performance. This makes the MIB assay a simple, affordable, and rapid assay for monitoring changes in cellular signaling.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/metabolismo , Proteômica/métodos , Tripsina/farmacologia , Bioensaio , Humanos , Espectrometria de Massas , Neoplasias/metabolismo , Neoplasias/patologia , Proteínas Quinases/química , Transdução de Sinais , Células Tumorais Cultivadas
13.
Nature ; 477(7363): 207-10, 2011 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-21832995

RESUMO

Atlantic cod (Gadus morhua) is a large, cold-adapted teleost that sustains long-standing commercial fisheries and incipient aquaculture. Here we present the genome sequence of Atlantic cod, showing evidence for complex thermal adaptations in its haemoglobin gene cluster and an unusual immune architecture compared to other sequenced vertebrates. The genome assembly was obtained exclusively by 454 sequencing of shotgun and paired-end libraries, and automated annotation identified 22,154 genes. The major histocompatibility complex (MHC) II is a conserved feature of the adaptive immune system of jawed vertebrates, but we show that Atlantic cod has lost the genes for MHC II, CD4 and invariant chain (Ii) that are essential for the function of this pathway. Nevertheless, Atlantic cod is not exceptionally susceptible to disease under natural conditions. We find a highly expanded number of MHC I genes and a unique composition of its Toll-like receptor (TLR) families. This indicates how the Atlantic cod immune system has evolved compensatory mechanisms in both adaptive and innate immunity in the absence of MHC II. These observations affect fundamental assumptions about the evolution of the adaptive immune system and its components in vertebrates.


Assuntos
Gadus morhua/genética , Gadus morhua/imunologia , Genoma/genética , Sistema Imunitário/imunologia , Imunidade/genética , Animais , Evolução Molecular , Genômica , Hemoglobinas/genética , Imunidade/imunologia , Complexo Principal de Histocompatibilidade/genética , Complexo Principal de Histocompatibilidade/imunologia , Masculino , Polimorfismo Genético/genética , Sintenia/genética , Receptores Toll-Like/genética
14.
Biochim Biophys Acta ; 1854(1): 84-90, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25448019

RESUMO

Transient transfection of mammalian cells with plasmid expression vectors and chemical transfection reagents is widely used to study protein transport and dynamics as well as phenotypic alterations mediated by the overexpressed protein. Despite the undisputed impact of this technique, surprisingly little is known about the cellular effects mediated by the transfection process per se. Conceivably, off-target effects could have implications upon proteins or processes being studied and understanding the molecular pathways affected would add value to the interpretation of experimental observations subsequent to cell transfection. Here we have used a SILAC-based proteomic approach to study differentially expressed proteins after transfection of HeLa cells with ECFP vector using a commonly employed non-liposome based transfection reagent, Fugene®HD. Whereas the transfection reagent itself mediated minimal effects upon protein expression, 11 proteins were found to be significantly upregulated after transfection, all of which were associated with an interferon type I/II response. The upregulated proteins might potentially inflict major cellular processes such as RNA splicing, chromatin remodeling, post-translational protein modification and cell cycle control. The results were validated by western analysis as well as quantitative RT-PCR and this demonstrated that an essentially identical response was induced in HeLa by transfection using an empty pUC18 vector, which does not contain a mammalian virus promoter, as well as a liposome-based transfection reagent, Lipofectamine(TM)2000. Notably, no induction of the interferon response was observed in HEK293 cells, suggesting that these cells might be preferable to HeLa to avoid undesired off-target effects in transfection studies encompassing interferon-signaling and antiviral responses.


Assuntos
Plasmídeos/genética , Proteoma/metabolismo , Proteômica/métodos , Transfecção/métodos , Western Blotting , Isótopos de Carbono/metabolismo , Cromatografia Líquida/métodos , Expressão Gênica , Células HEK293 , Células HeLa , Humanos , Marcação por Isótopo/métodos , Lipídeos/química , Lisina/metabolismo , Proteoma/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espectrometria de Massas em Tandem/métodos
16.
J Assoc Physicians India ; 63(7): 54-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26731829

RESUMO

Organising pneumonia is a histopathological entity characterised by intra-alveolar buds of granulation tissue, intermixed myofibroblasts and connective tissue. Cryptogenic organising pneumonia (COP) is characterised by this particular histopathological pattern, along with typical clinical and imaging features, when no other underlying aetiology is found. COP (previously known as bronchiolitis obliterans organising pneumonia [BOOP]) is one of the rare variants of interstitial pneumonias. This condition is characterised by a rapid clinical and radiological improvement with steroid treatment. Here we are reporting a case of COP in adult female with discussion on approach and basic pathophysiology of this type of pneumonia.


Assuntos
Pneumonia em Organização Criptogênica/diagnóstico , Pneumonia em Organização Criptogênica/etiologia , Pneumonia em Organização Criptogênica/fisiopatologia , Feminino , Humanos , Pessoa de Meia-Idade
17.
Am J Physiol Regul Integr Comp Physiol ; 306(9): R627-35, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24573184

RESUMO

How sex steroids modulate glucocorticoid feedback on the hypothalamic-pituitary-corticotrope (HPC) unit is controversial in humans. We postulated that testosterone (T) in men and estradiol (E2) in women govern unstressed cortisol-mediated negative feedback on ACTH secretion. To test this hypothesis, 24 men and 24 women age 58 ± 2.4 yr were pretreated with leuprolide and either sex steroid (E2 in women, T in men) or placebo addback. Placebo or ketoconazole (KTCZ) was administered overnight to inhibit adrenal steroidogenesis during overnight 14-h intravenous infusions of saline or cortisol in a continuous versus pulsatile manner to test for feedback differences. ACTH was measured every 10 min during the last 8 h of the infusions. The main outcome measures were mean ACTH concentrations, pulsatile ACTH secretion, and ACTH approximate entropy (ApEn). ACTH concentrations were lower in women than men (P < 0.01), and in women in the E2+ compared with E2- group under both continuous (P = 0.01) and pulsatile (P = 0.006) cortisol feedback, despite higher cortisol binding globulin and lower free cortisol levels in women than men (P < 0.01). In the combined groups, under both modes of cortisol addback, ACTH concentrations, pulsatile ACTH secretion, and ACTH secretory-burst mass correlated negatively and univariately with E2 levels (each P < 0.005). E2 also suppressed ACTH ApEn (process randomness) during continuous cortisol feedback (P = 0.004). T had no univariate effect but was a positive correlate of ACTH when assessed jointly with E2 (negative) under cortisol pulses. In conclusion, sex steroids modulate selective gender-related hypothalamic-pituitary adrenal-axis adaptations to cortisol feedback in unstressed humans.


Assuntos
Hormônio Adrenocorticotrópico/metabolismo , Envelhecimento/fisiologia , Estradiol/administração & dosagem , Hidrocortisona/administração & dosagem , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Testosterona/análogos & derivados , Hormônio Adrenocorticotrópico/sangue , Fatores Etários , Estudos Cross-Over , Método Duplo-Cego , Esquema de Medicação , Inibidores Enzimáticos/administração & dosagem , Retroalimentação Fisiológica , Feminino , Humanos , Hipogonadismo/induzido quimicamente , Hipogonadismo/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Infusões Intravenosas , Cetoconazol/administração & dosagem , Leuprolida/administração & dosagem , Masculino , Pessoa de Meia-Idade , Sistema Hipófise-Suprarrenal/metabolismo , Estudos Prospectivos , Ligação Proteica , Albumina Sérica/metabolismo , Albumina Sérica Humana , Fatores Sexuais , Testosterona/administração & dosagem , Fatores de Tempo , Transcortina/metabolismo
18.
Pediatr Diabetes ; 15(6): 444-52, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24350820

RESUMO

CONTEXT: Type 1 diabetes mellitus (T1DM) is a pro-inflammatory stress state, which, with its attendant hyperglycemia, likely disrupts hypothalamo-pituitary-adrenal (HPA) control, further dysregulating glucose homeostasis. OBJECTIVE: To test the hypothesis that endogenous adrenocorticotropic hormone (ACTH)-cortisol dose-responsive drive, estimated analytically, is significantly accentuated in adolescents and young adults with T1DM compared with healthy individuals. DESIGN, SETTING, PATIENTS, AND INTERVENTIONS: This was a pilot study of 11 volunteers with T1DM and 10 controls, ages 16-30 yr, at a medical center. Subjects underwent overnight frequent blood sampling (every 10 min for ACTH and cortisol and every 60 min for blood glucose) from 10 pm to 8 am. T1DM volunteers maintained their home insulin regimen. MAIN OUTCOMES: Deconvolution analysis and dose-response estimates were the key outcomes. RESULTS: Mean free cortisol, but not ACTH, concentrations were lower in the T1DM group compared with controls (p = 0.012). Non-invasive ACTH-cortisol dose-response estimates revealed that T1DM patients had reduced ACTH efficacy (maximal cortisol secretion, p = 0.009), reduced ACTH potency as quantified by greater EC50 (ACTH concentration driving half-maximal cortisol secretion, p = 0.04), and increased ACTH sensitivity (more positive ACTH-cortisol slope, p = 0.03). Post-hoc gender comparisons indicated that these differences were limited to females. Linear regression in women showed a strong correlation of both ACTH efficacy and EC50 with C-peptide levels (both p < 0.01). CONCLUSION: Compared with healthy individuals, T1DM patients manifest decreased overnight adrenal responsiveness to endogenous ACTH leading to lower free cortisol concentrations. These findings suggest impaired stress-related adaptations of the HPA axis in T1DM.


Assuntos
Hormônio Adrenocorticotrópico/sangue , Ritmo Circadiano/fisiologia , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/fisiopatologia , Hidrocortisona/metabolismo , Sistema Hipotálamo-Hipofisário , Adolescente , Adulto , Estudos de Casos e Controles , Regulação para Baixo , Feminino , Humanos , Hidrocortisona/sangue , Sistema Hipotálamo-Hipofisário/metabolismo , Sistema Hipotálamo-Hipofisário/fisiopatologia , Masculino , Projetos Piloto , Adulto Jovem
19.
Food Chem ; 446: 138863, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38428084

RESUMO

Brewer's spent grain (BSG) is an abundant agro-industrial residue and a sustainable low-cost source for extracting proteins. The composition and functionality of BSG protein concentrates are affected by extraction conditions. This study examined the use of citric acid (CA) and HCl to precipitate BSG proteins. The resultant protein concentrates were compared in terms of their composition and functional properties. The BSG protein concentrate precipitated by CA had 10% lower protein content, 5.8% higher carbohydrate, and 5.4% higher lipid content than the sample precipitated by HCl. Hydrophilic/hydrophobic protein and saturated/unsaturated fatty acid ratios increased by 16.9% and 26.5% respectively, in the sample precipitated by CA. The formation of CA-cross-linkages was verified using shotgun proteomics and Fourier transform infrared spectroscopy. Precipitation by CA adversely affected protein solubility and emulsifying properties, while improving foaming properties. This study provides insights into the role of precipitants in modulating the properties of protein concentrates.


Assuntos
Proteínas de Grãos , Proteínas de Grãos/análise , Ácido Clorídrico , Grão Comestível/química
20.
J Endocr Soc ; 7(7): bvad065, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37388573

RESUMO

Context: Childhood papillary thyroid carcinoma (CPTC), despite bilateral thyroidectomy, nodal dissection and radioiodine remnant ablation (RRA), recurs within neck nodal metastases (NNM) in 33% within 20 postoperative years. These NNM are usually treated with reoperation or further radioiodine. Ethanol ablation (EA) may be considered when numbers of NNM are limited. Objective: We studied the long-term results of EA in 14 patients presenting with CPTC during 1978 to 2013 and having EA for NNM during 2000 to 2018. Methods: Cytologic diagnoses of 20 NNM (median diameter 9 mm; median volume 203 mm3) were biopsy proven. EA was performed during 2 outpatient sessions under local anesthesia; total volume injected ranged from 0.1 to 2.8 cc (median 0.7). All were followed regularly by sonography and underwent volume recalculation and intranodal Doppler flow measurements. Successful ablation required reduction both in NNM volume and vascularity. Results: Post EA, patients were followed for 5 to 20 years (median 16). There were no complications, including postprocedure hoarseness. All 20 NNM shrank (mean by 87%) and Doppler flow eliminated in 19 of 20. After EA, 11 NNM (55%) disappeared on sonography; 8 of 11 before 20 months. Nine ablated foci were still identifiable after a median of 147 months; only one identifiable 5-mm NNM retained flow. Median serum Tg post EA was 0.6 ng/mL. Only one patient had an increase in Tg attributed to lung metastases. Conclusion: EA of NNM in CPTC is effective and safe. Our results suggest that for CPTC patients who do not wish further surgery and are uncomfortable with active surveillance of NNM, EA represents a minimally invasive outpatient management option.

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