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1.
J Sci Food Agric ; 104(2): 809-817, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37743408

RESUMO

BACKGROUND: There is limited knowledge regarding digestion and absorption of nutrients after cooked marinated meat is ingested. Most of the previous studies on food gastric digestion have focused on chemical digestion and did not reflect upon physical digestion driven by peristalsis. In the present study, we examined the effects of marinating beef in lemon juice on gastric digestibility using a human gastric digestion simulator (GDS) that mimics peristaltic motion called antral contraction waves. RESULTS: Beef thigh slices were marinated in 100% lemon juice for 1 h and then grilled; an image of a stained tissue sample revealed that muscle tissue contraction (i.e. that usually occurs upon cooking) was suppressed. The measurement of physical properties using a rheometer and texture analyzer showed that the meat marinated in lemon juice had a soft texture. In vitro digestion experiments using the GDS revealed that the extent of both physical digestion driven by peristalsis and chemical digestion catalyzed by digestive enzymes was enhanced by the lemon juice marinade. CONCLUSION: The results of the present study suggest that marinating beef in lemon juice affects nutrient digestibility. An integrated evaluation of tissue structure, physical properties and GDS digestion to analyze meat digestion would enhance our understanding of the effects of seasoning and cooking methods on meat. © 2023 Society of Chemical Industry.


Assuntos
Culinária , Carne , Animais , Bovinos , Humanos , Culinária/métodos , Carne/análise , Estômago , Nutrientes
2.
EMBO J ; 42(23): e113798, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37849386

RESUMO

Based on studies of animals and yeasts, methylation of histone H3 lysine 4 (H3K4me1/2/3, for mono-, di-, and tri-methylation, respectively) is regarded as the key epigenetic modification of transcriptionally active genes. In plants, however, H3K4me2 correlates negatively with transcription, and the regulatory mechanisms of this counterintuitive H3K4me2 distribution in plants remain largely unexplored. A previous genetic screen for factors regulating plant regeneration identified Arabidopsis LYSINE-SPECIFIC DEMETHYLASE 1-LIKE 3 (LDL3), which is a major H3K4me2 demethylase. Here, we show that LDL3-mediated H3K4me2 demethylation depends on the transcription elongation factor Paf1C and phosphorylation of the C-terminal domain (CTD) of RNA polymerase II (RNAPII). In addition, LDL3 binds to phosphorylated RNAPII. These results suggest that LDL3 is recruited to transcribed genes by binding to elongating RNAPII and demethylates H3K4me2 cotranscriptionally. Importantly, the negative correlation between H3K4me2 and transcription is significantly attenuated in the ldl3 mutant, demonstrating the genome-wide impacts of the transcription-driven LDL3 pathway to control H3K4me2 in plants. Our findings implicate H3K4me2 demethylation in plants as chromatin records of transcriptional activity, which ensures robust gene control.


Assuntos
Arabidopsis , Animais , Arabidopsis/genética , Arabidopsis/metabolismo , Histonas/genética , Histonas/metabolismo , Lisina/metabolismo , Cromatina/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , Plantas/metabolismo , Desmetilação
3.
Curr Protoc ; 3(1): e648, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36629495

RESUMO

The chemical synthesis of a riboside phosphoramidite has been achieved to provide a 5-O-capture linker and a 2-O-silyl ether protecting group with the intent of enabling an efficient solid-phase purification of synthetic DNA sequences. The riboside phosphoramidite has been incorporated into a DNA sequence while performing the penultimate automated solid-phase synthesis cycle of the sequence. The terminal 5-O-riboside moiety of the resulting DNA sequence is then conjugated to a capture linker to create an anchor for the solid-phase purification of the DNA sequence conjugate. Release of all DNA sequences from the synthesis support is achieved under standard basic conditions to yield a mixture of the desired DNA sequence conjugate along with unconjugated, shorter-than-full-length sequence contaminants. Upon exposure of all DNA sequences to a capture solid support, only the DNA sequence conjugate is chemoselectively captured, thereby allowing the unconjugated shorter-than-full-length DNA sequences to be efficiently washed away from the capture support. After 2-O-cleavage of the silyl ether protecting group from the terminal riboside ethylphosphate triester conjugate, the solid-phase-purified DNA sequence is efficiently released from the capture support through an innovative intramolecular cyclodeesterification of the ethylphosphate triester, prompted by the riboside's rigid cis-diol conformer, to provide a highly pure DNA sequence. Published 2023. This article is a U.S. Government work and is in the public domain in the USA. Basic Protocol 1: Preparation of 5-O-(4,4'-dimethoxytrityl)-2-O-tert-butyldimethylsilyl-1,4-anhydro-D-ribitol (3) Basic Protocol 2: Preparation of 5-O-(4,4'-dimethoxytrityl)-2-O-tert-butyldimethylsilyl-3-O-[(N,N-diisopropylamino)ethyloxyphosphinyl]-1,4-anhydro-D-ribitol (6). Basic Protocol 3: Automated synthesis of the chimeric solid-phase-linked DNA sequence 8. Support Protocol: Preparation of 2-cyanoethyl-(5-oxohexyl)-N,N-diisopropylphosphoramidite (9). Basic Protocol 4: Solid-phase purification of the chimeric DNA sequence 10.


Assuntos
Ácidos Nucleicos , Técnicas de Síntese em Fase Sólida , Compostos Organofosforados
4.
Nat Commun ; 13(1): 4521, 2022 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-35953471

RESUMO

Mono-, di-, and trimethylation of histone H3 lysine 4 (H3K4me1/2/3) are associated with transcription, yet it remains controversial whether H3K4me1/2/3 promote or result from transcription. Our previous characterizations of Arabidopsis H3K4 demethylases suggest roles for H3K4me1 in transcription. However, the control of H3K4me1 remains unexplored in Arabidopsis, in which no methyltransferase for H3K4me1 has been identified. Here, we identify three Arabidopsis methyltransferases that direct H3K4me1. Analyses of their genome-wide localization using ChIP-seq and machine learning reveal that one of the enzymes cooperates with the transcription machinery, while the other two are associated with specific histone modifications and DNA sequences. Importantly, these two types of localization patterns are also found for the other H3K4 methyltransferases in Arabidopsis and mice. These results suggest that H3K4me1/2/3 are established and maintained via interplay with transcription as well as inputs from other chromatin features, presumably enabling elaborate gene control.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Animais , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Metilação de DNA/genética , Epigenoma , Histonas/genética , Histonas/metabolismo , Metilação , Metiltransferases/genética , Camundongos
5.
Curr Protoc ; 2(1): e346, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35030289

RESUMO

The implementation of protecting groups for 2'-hydroxyl function of ribonucleosides is very demanding in that synthetic RNA sequences must be highly pure to ensure the safety and efficacy of nucleic acid-based drugs for treatment of human diseases. A synthetic approach consisting of a condensation reaction between 2'-O-aminoribonucleosides with ethyl pyruvate has been employed to provide stable 2'-O-imino-2-methyl propanoic acid ethyl esters. Conversion of these esters to fully protected ribonucleoside phosphoramidite monomers has allowed rapid and efficient incorporation of 2'-O-protected ribonucleosides into RNA sequences while minimizing the formation of process-related impurities during solid-phase synthesis. Two chimeric 20-mer RNA sequences have been synthesized and then exposed to a solution of sodium hydroxide to saponify the 2'-O-imino-2-methyl propanoic acid ethyl ester protecting groups to their sodium salts. When subjected to ion-exchange conditions at 65°C and near neutral pH, fully deprotected RNA sequences are isolated without production of alkylating side-products and/or formation of mutagenic nucleobase adducts. © 2022 Wiley Periodicals LLC. This article has been contributed to by US Government employees and their work is in the public domain in the USA. Basic Protocol 1: Synthesis of uridine 2'-O-imino-2-propanoic acid ethyl ester and its fully protected 3'-O-phosphoramidite Basic Protocol 2: Synthesis of N6 -protected adenosine 2'-O-imino-2-propanoic acid ethyl ester and its fully protected 3'-O-phosphoramidite Basic Protocol 3: Synthesis of N4 -protected cytidine 2'-O-imino-2-propanoic acid ethyl ester and its fully protected 3'-O-phosphoramidite Basic Protocol 4: Synthesis of N2 -protected guanosine 2'-O-imino-2-propanoic acid ethyl ester and its fully protected 3'-O-phosphoramidite Basic Protocol 5: Automated solid-phase RNA synthesis and deprotection using 2'-O-imino-2-proponate-protected phosphoramidites.


Assuntos
Ribonucleosídeos , Técnicas de Síntese em Fase Sólida , Arabinonucleosídeos , Sequência de Bases , Humanos , RNA
6.
Curr Protoc ; 1(5): e108, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33945676

RESUMO

The preparation of controlled pore glass (CPG) supports, functionalized with several hexaethylene glycol spacers, to alleviate the problems associated with the porosity of commercial CPG supports is described in this article. The pore size of CPG restricts the diffusion of reagents to the leader nucleoside embedded in porous supports; this inhibits efficient solid-phase syntheses of DNA and RNA sequences and, by default, the purity of those sequences through formation of a shorter than full-length oligonucleotide. Functionalization of a CPG support with five hexaethylene glycol spacers led to a 42% reduction in process-related impurities contaminating oligonucleotide sequences, compared to that obtained using the commercial long-chain alkylamine (LCAA) CPG support. © 2021 Wiley Periodicals LLC. This article has been contributed to by US Government employees and their work is in the public domain in the USA. Basic Protocol 1: Preparation of the hydroxylated CPG support 3 Basic Protocol 2: Automated preparation of the CPG support 6 Basic Protocol 3: Automated preparation of the poly(hexaethylene glycol)-derived CPG 7 Basic Protocol 4: Automated functionalization of the poly(hexaethylene glycol)-derived CPG support 7 with leader deoxyribo- and ribonucleosides to provide the CPG support 9 Basic Protocol 5: Automated syntheses of DNA and RNA sequences on poly(hexaethylene glycol)-derived CPG support 9 and on a commercial long-chain alkylamine (LCAA) CPG support Support Protocol: Release and deprotection of the DNA and RNA sequences linked to the poly(hexaethylene glycol)-derived CPG support 10 and commercial LCAA-CPG support Basic Protocol 6: Comparative RP-HPLC analyses of crude, fully deprotected DNA or RNA sequences released from the poly(hexaethylene glycol)-derived CPG support 10 and from a commercial LCAA-CPG support.


Assuntos
DNA , Técnicas de Síntese em Fase Sólida , Sequência de Bases , Vidro , Oligonucleotídeos
7.
J Org Chem ; 86(7): 4944-4956, 2021 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-33706514

RESUMO

The implementation of protecting groups for the 2'-hydroxyl function of ribonucleosides is still challenging, particularly when RNA sequences must be of the highest purity for therapeutic applications as nucleic acid-based drugs. A 2'-hydroxyl-protecting group should optimally (i) be easy to install; (ii) allow rapid and efficient incorporation of the 2'-O-protected ribonucleosides into RNA sequences to minimize, to the greatest extent possible, the formation of process-related impurities (e.g., shorter than full-length sequences) during solid-phase synthesis; and (iii) be completely cleaved from RNA sequences without the production of alkylating side products and/or formation of mutagenic nucleobase adducts. The reaction of 2'-O-aminoribonucleosides with ethyl pyruvate results in the formation of stable 2'-O-imino-2-methyl propanoic acid ethyl esters and, subsequently, of the fully protected ribonucleoside phosphoramidite monomers, which are required for the solid-phase synthesis of two chimeric RNA sequences (20-mers) containing the four canonical ribonucleosides. Upon treatment of the RNA sequences with a solution of sodium hydroxide, the 2'-O-imino-2-methyl propanoic acid ethyl ester-protecting groups are saponified to their sodium salts, which after ion exchange underwent quantitative intramolecular decarboxylation under neutral conditions at 65 °C to provide fully deprotected RNA sequences in marginally better yields than those obtained from commercial 2'-O-tert-butyldimethylsilyl ribonucleoside phosphoramidites under highly similar conditions.


Assuntos
Ribonucleosídeos , Técnicas de Síntese em Fase Sólida , Sequência de Bases , Compostos Organofosforados , Propionatos , RNA
8.
Nat Plants ; 7(3): 295-302, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33649596

RESUMO

In eukaryotic genomes, the transcription units of genes often overlap with other protein-coding and/or noncoding transcription units1,2. In such intertwined genomes, the coordinated transcription of nearby or overlapping genes would be important to ensure the integrity of genome function3-6; however, the mechanisms underlying this coordination are largely unknown. Here, we show in Arabidopsis thaliana that genes with convergent orientation of transcription are major sources of antisense transcripts and that these genes transcribed on both strands are regulated by a putative Lysine-Specific Demethylase 1 family histone demethylase, FLOWERING LOCUS D (FLD)7,8. Our genome-wide chromatin profiling revealed that FLD, as well as its associating factor LUMINIDEPENDENS9, downregulates histone H3K4me1 in regions with convergent overlapping transcription. FLD localizes to actively transcribed genes, where it colocalizes with elongating RNA polymerase II phosphorylated at the Ser2 or Ser5 sites. Genome-wide transcription analyses suggest that FLD-mediated H3K4me1 removal negatively regulates the transcription of genes with high levels of antisense transcription. Furthermore, the effect of FLD on transcription dynamics is antagonized by DNA topoisomerase I. Our study reveals chromatin-based mechanisms to cope with overlapping transcription, which may occur by modulating DNA topology. This global mechanism to cope with overlapping transcription could be co-opted for specific epigenetic processes, such as cellular memory of responses to the environment10.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Cromatina/fisiologia , Regulação da Expressão Gênica de Plantas , Histona Desacetilases/genética , Proteínas de Domínio MADS/genética , Proteínas de Arabidopsis/fisiologia , Histonas/genética , Transcrição Gênica
9.
Bioorg Med Chem ; 28(22): 115779, 2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-33007546

RESUMO

With the intent of mitigating the formation of process-related impurities during solid-phase synthesis of DNA or RNA sequences, a hydroxylated controlled-pore glass support conjugated to three, five or seven hexaethylene glycol spacers was prepared and demonstrated to provide a more efficient and robust synthesis process. Indeed, the use of a support conjugated to five hexaethylene glycol spacers led to a 19% up to 42% reduction of process-related impurities contaminating synthetic nucleic acid sequences, when compared to that obtained from the same DNA/RNA sequences synthesized using a commercial long-chain alkylamine controlled-pore glass support under highly similar conditions.


Assuntos
DNA/síntese química , Preparações Farmacêuticas/síntese química , RNA/síntese química , Técnicas de Síntese em Fase Sólida , Sequência de Bases , DNA/química , Etilenoglicóis , Preparações Farmacêuticas/química , RNA/química
10.
Microbiol Immunol ; 64(11): 747-761, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32910457

RESUMO

The human herpesvirus 6B (HHV-6B) U79/80 gene belongs to the early gene class and appears as early as 3 hr postinfection. It is one of the most abundantly expressed transcripts and a useful diagnostic marker for viral reactivation. However, the expression mechanisms of the U79/80 gene remain unclear. To identify the viral factor(s) that activates the U79/80 promoter along with other HHV-6B core early gene promoters, p41, DNA polymerase, and U41, we examined the activities of U79/80 and other early gene promoters. In HHV-6B-infected MT-4 cells, U79/80 promoter activity was the highest among early gene promoters. In addition, we identified that HHV-6B immediate-early (IE)2B protein is one of the viral proteins involved in the activation of the U79/80 and other early gene promoters. Although the IE2B could independently activate these early gene promoters, the presence of IE1B significantly augmented the activities of early gene promoters. We also found that IE2B bound three human cytomegalovirus IE2-binding consensus, cis repression signal (CRS), within the U79/80 promoter. Moreover, the U79/80 promoter was activated by cellular factors, which are highly expressed in MT-4 cells, instead of HeLa cells because it was upregulated by mock infection and in the absence of IE2B. These results suggested that the activation mechanism of the U79/80 gene differs from other HHV-6B core early genes, apparently supporting its rapid and abundant expression. Therefore, the U79/80 early gene is an actually suitable biomarker of HHV-6B reactivation.


Assuntos
Herpesvirus Humano 6/genética , Herpesvirus Humano 6/metabolismo , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Regiões Promotoras Genéticas , Proteínas Virais/genética , Proteínas Virais/metabolismo , Citomegalovirus/genética , DNA Polimerase Dirigida por DNA , Regulação Viral da Expressão Gênica , Células HeLa , Humanos , Transcrição Gênica , Ativação Transcricional
11.
Intern Med ; 59(24): 3235-3238, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32788531

RESUMO

Thrombotic microangiopathy (TMA) is a rare but life-threatening complication of systemic lupus erythematosus (SLE) and is associated with adverse pregnancy outcomes. We herein report a 30-year-old pregnant woman with SLE complicated by TMA. Because her condition was unresponsive to initial corticosteroid and fresh-frozen plasma infusion treatment, we attempted plasma exchange (PE). Although thrombocytopenia and microangiopathic hemolytic anemia gradually improved, fetal death was confirmed at 23 weeks of gestation. This case suggests that PE is an effective therapeutic option but might be insufficient to maintain pregnancy in patients with SLE complicated by TMA.


Assuntos
Lúpus Eritematoso Sistêmico , Púrpura Trombocitopênica Trombótica , Microangiopatias Trombóticas , Adulto , Feminino , Humanos , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/terapia , Troca Plasmática , Gravidez , Resultado da Gravidez , Púrpura Trombocitopênica Trombótica/complicações , Púrpura Trombocitopênica Trombótica/diagnóstico , Púrpura Trombocitopênica Trombótica/terapia , Microangiopatias Trombóticas/diagnóstico , Microangiopatias Trombóticas/etiologia , Microangiopatias Trombóticas/terapia
12.
iScience ; 23(6): 101187, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32534440

RESUMO

Little is known about the effect of latent-phase herpesviruses on their host. Human herpesvirus 6B (HHV-6B) is one of the most ubiquitous herpesviruses, and olfactory astrocytes are one of the most important sites of its latency. Here, we identified SITH-1, an HHV-6B latent protein specifically expressed in astrocytes. Mice induced to produce SITH-1 in their olfactory astrocytes exhibited olfactory bulb apoptosis, a hyper-activated hypothalamic-pituitary-adrenal (HPA) axis and depressive symptoms. The binding of SITH-1 to the host protein calcium-modulating ligand (CAML) to form an activated complex promoted the influx of extracellular calcium. The serum antibody titers for depressive patients with respect to this activated complex were significantly higher than for normal controls (p = 1.78 × 10-15), when the antibody positive rates were 79.8% and 24.4%, respectively, and the odds ratio was 12.2. These results suggest that, in the latent phase, HHV-6B may be involved in the onset of depression.

13.
Nucleic Acids Res ; 48(9): 4643-4657, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32282904

RESUMO

We report on the synthesis of siRNAs containing both 2'-5'- and 3'-5'-internucleotide linkages and their effects on siRNA structure, function, and interaction with RNAi proteins. Screening of these siRNAs against their corresponding mRNA targets showed that 2'-5' linkages were well tolerated in the sense strand, but only at a few positions in the antisense strand. Extensive modification of the antisense strand minimally affected 5'-phosphorylation of the siRNA by kinases, however, it negatively affected siRNA loading into human AGO2. Modelling and molecular dynamics simulations were fully consistent with these findings. Furthermore, our studies indicated that the presence of a single 5'p-rN1-(2'-5')-N2 unit in the antisense strand does not alter the 'clover leaf' bend and sugar puckers that are critical for anchoring the 5'-phosphate to Ago 2 MID domain. Importantly, 2'-5'-linkages had the added benefit of abrogating immune-stimulatory activity of siRNAs. Together, these results demonstrate that 2'-5'/3'-5'-modified siRNAs, when properly designed, can offer an efficient new class of siRNAs with diminished immune-stimulatory responses.


Assuntos
Interferência de RNA , RNA Interferente Pequeno/química , Proteínas Argonautas/metabolismo , Configuração de Carboidratos , Células HeLa , Humanos , Luciferases de Vaga-Lume/genética , Simulação de Dinâmica Molecular , Conformação de Ácido Nucleico , RNA Interferente Pequeno/síntese química , RNA Interferente Pequeno/imunologia , Proteína Supressora de Tumor p53/genética
14.
Front Immunol ; 11: 629399, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33633747

RESUMO

Neoantigen formation due to the interaction of drug molecules with human leukocyte antigen (HLA)-peptide complexes can lead to severe hypersensitivity reactions. Flucloxacillin (FLX), a ß-lactam antibiotic for narrow-spectrum gram-positive bacterial infections, has been associated with severe immune-mediated drug-induced liver injury caused by an influx of T-lymphocytes targeting liver cells potentially recognizing drug-haptenated peptides in the context of HLA-B*57:01. To identify immunopeptidome changes that could lead to drug-driven immunogenicity, we used mass spectrometry to characterize the proteome and immunopeptidome of B-lymphoblastoid cells solely expressing HLA-B*57:01 as MHC-I molecules. Selected drug-conjugated peptides identified in these cells were synthesized and tested for their immunogenicity in HLA-B*57:01-transgenic mice. T cell responses were evaluated in vitro by immune assays. The immunopeptidome of FLX-treated cells was more diverse than that of untreated cells, enriched with peptides containing carboxy-terminal tryptophan and FLX-haptenated lysine residues on peptides. Selected FLX-modified peptides with drug on P4 and P6 induced drug-specific CD8+ T cells in vivo. FLX was also found directly linked to the HLA K146 that could interfere with KIR-3DL or peptide interactions. These studies identify a novel effect of antibiotics to alter anchor residue frequencies in HLA-presented peptides which may impact drug-induced inflammation. Covalent FLX-modified lysines on peptides mapped drug-specific immunogenicity primarily at P4 and P6 suggesting these peptide sites as drivers of off-target adverse reactions mediated by FLX. FLX modifications on HLA-B*57:01-exposed lysines may also impact interactions with KIR or TCR and subsequent NK and T cell function.


Assuntos
Floxacilina/imunologia , Antígenos HLA-B/imunologia , Haptenos/imunologia , Peptídeos/imunologia , Animais , Linhagem Celular , Antígenos HLA-B/genética , Humanos , Camundongos , Camundongos Transgênicos , Peptídeos/genética
15.
Mol Ther Nucleic Acids ; 17: 615-625, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31394430

RESUMO

Currently, the most effective and durable therapeutic option for HIV-1 infection is combination antiretroviral therapy (cART). Although cART is powerful and can delay viral evolution of drug resistance for decades, it is associated with limitations, including an inability to eradicate the virus and a potential for adverse effects. Therefore, it is imperative to discover new HIV therapeutic modalities. In this study, we designed, characterized, and evaluated the in vitro potency of 2'-deoxy-2'-fluoroarabinonucleotide (FANA) modified antisense oligonucleotides (ASOs) targeting highly conserved regions in the HIV-1 genome. Carrier-free cellular internalization of FANA ASOs resulted in strong suppression of HIV-1 replication in HIV-1-infected human primary cells. In vitro mechanistic studies suggested that the inhibitory effect of FANA ASOs can be attributed to RNase H1 activation and steric hindrance of dimerization. Using 5'-RACE PCR and sequencing analysis, we confirmed the presence of human RNase H1-mediated target RNA cleavage products in cells treated with FANA ASOs. We observed no overt cytotoxicity or immune responses upon FANA ASO treatment. Together, our results strongly suggest that FANA ASOs hold great promise for antiretroviral therapy. The dual ability of FANA ASOs to target RNA by recruiting RNase H1 and/or sterically blocking RNA dimerization further enhances their therapeutic potential.

16.
Curr Protoc Nucleic Acid Chem ; 77(1): e84, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30970180

RESUMO

The physiological functions of c-di-GMP and its involvement in many key processes led to its recognition as a major and ubiquitous bacterial second messenger. Aside from being a bacterial signaling molecule, c-di-GMP is also an immunostimulatory molecule capable of inducing innate and adaptive immune responses through maturation of immune mammalian cells. Given the broad biological functions of c-di-GMP and its potential applications as a nucleic-acid-based drug, the chemical synthesis of c-di-GMP has drawn considerable interest. An improved phosphoramidite approach to the synthesis of c-di-GMP is reported herein. The synthetic approach is based on the use of a 5'-O-formyl protecting group, which can be rapidly and chemoselectively cleaved from a key dinucleotide phosphoramidite intermediate to enable a cyclocondensation reaction leading to a fully protected c-di-GMP product in a yield ∼80%. The native c-di-GMP is isolated, after complete deprotection, in an overall yield of 36% based on the commercial ribonucleoside used as starting material. © 2019 by John Wiley & Sons, Inc.


Assuntos
GMP Cíclico/análogos & derivados , Amidas/química , Amidas/isolamento & purificação , GMP Cíclico/síntese química , Ésteres/química , Ácidos Fosfóricos/química , Ácidos Fosfóricos/isolamento & purificação , Ribonucleosídeos/síntese química
17.
Antioxidants (Basel) ; 8(3)2019 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-30862106

RESUMO

Mitochondrial function has been closely associated with normal aging and age-related diseases. Age-associated declines in mitochondrial function, such as changes in oxygen consumption rate, cytochrome c oxidase activity of complex IV, and mitochondrial coenzyme Q (CoQ) levels, begin as early as 12 to 15 months of age in male mouse brains. Brain mitochondrial dysfunction is accompanied by increased accumulation of phosphorylated α-synuclein in the motor cortex and impairment of motor activities, which are similar characteristics of Parkinson's disease. However, these age-associated defects are completely rescued by the administration of exogenous CoQ10 to middle-aged mice via its water solubilization by emulsification in drinking water. Further efforts to develop strategies to enhance the biological availability of CoQ10 to successfully ameliorate age-related brain mitochondrial dysfunction or neurodegenerative disorders may provide a promising anti-aging agent.

18.
Lab Invest ; 99(6): 793-806, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30710119

RESUMO

Although inhibition of epidermal growth factor receptor (EGFR)-mediated cell signaling by the EGFR tyrosine kinase inhibitor gefitinib is highly effective against advanced non-small cell lung cancer, this drug might promote severe acute interstitial pneumonia. We previously reported that molecular hydrogen (H2) acts as a therapeutic and preventive anti-oxidant. Here, we show that treatment with H2 effectively protects the lungs of mice from severe damage caused by oral administration of gefitinib after intraperitoneal injection of naphthalene, the toxicity of which is related to oxidative stress. Drinking H2-rich water ad libitum mitigated naphthalene/gefitinib-induced weight loss and significantly improved survival, which was associated with a decrease in lung inflammation and inflammatory cytokines in the bronchoalveolar lavage fluid. Naphthalene decreased glutathione in the lung, increased malondialdehyde in the plasma, and increased 4-hydroxy-2-nonenal production in airway cells, all of which were mitigated by H2-rich water, indicating that the H2-rich water reverses cellular damage to the bronchial wall caused by oxidative stress. Finally, treatment with H2 did not interfere with the anti-tumor effects of gefitinib on a lung cancer cell line in vitro or on tumor-bearing mice in vivo. These results indicate that H2-rich water has the potential to improve quality of life during gefitinib therapy by mitigating lung injury without impairing anti-tumor activity.


Assuntos
Lesão Pulmonar Aguda/prevenção & controle , Antineoplásicos/efeitos adversos , Gefitinibe/efeitos adversos , Hidrogênio/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Lesão Pulmonar Aguda/induzido quimicamente , Animais , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Feminino , Hidrogênio/farmacologia , Pulmão/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Naftalenos , Estresse Oxidativo/efeitos dos fármacos , Distribuição Aleatória
19.
J Diabetes Investig ; 10(2): 309-317, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30070047

RESUMO

AIMS/INTRODUCTION: The present study investigated the relationship between the macronutrient energy ratio, dietary carbohydrate and glycated hemoglobin levels in Japanese patients with type 2 diabetes, to generate a potential optimal dietary intake of macronutrients for such patients. MATERIALS AND METHODS: In total, 3,032 patients participating in the Sleep and Food Registry in Kanagawa study were evaluated. Their diets were assessed for macronutrient content through a brief self-administered dietary history questionnaire. Relevant biochemical assays were carried out. RESULTS: The mean energy intake (±standard deviation) was 1,711 ± 645 kcal/day. The proportion of energy supplied by protein, fat and carbohydrate were 16.3, 26.8 and 52.3%, respectively. Total fiber intake was 12.6 ± 5.7 g/day. The high glycated hemoglobin (HbA1c) group (HbA1c >8%) had significantly lower protein and higher carbohydrate intake than the low HbA1c group (HbA1c <6.5%). Higher HbA1c levels were positively correlated with unfavorable metabolic factors, including elevated body mass index and excess carbohydrate intake, and negatively correlated with age, protein intake and fiber intake. Multiple regression analysis showed a significant association between HbA1c and carbohydrate intake after adjusting for sex, age and body mass index (0.104, P < 0.0001). Additionally, patients within the uppermost tertile for the percentage of total energy intake from carbohydrate (>60%) were most likely to have high HbA1c levels. HbA1c was significantly correlated with carbohydrate (%E) in all age groups and in patients taking one or two antidiabetic drugs. CONCLUSIONS: The dietary carbohydrate:energy ratio has a positive correlation with HbA1c, suggesting that avoiding excessive carbohydrate intake (>60%) might help foster glycemic control.


Assuntos
Biomarcadores/sangue , Diabetes Mellitus Tipo 2/sangue , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Fibras na Dieta/administração & dosagem , Hemoglobinas Glicadas/análise , Idoso , Glicemia/análise , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/fisiopatologia , Ingestão de Energia , Feminino , Seguimentos , Índice Glicêmico , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Sistema de Registros , Inquéritos e Questionários
20.
Sci Rep ; 8(1): 16822, 2018 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-30429524

RESUMO

The main cause of arteriosclerosis is atherosclerosis in the aorta. Atherosclerosis is recognized as a chronic inflammatory condition that begins with the dysfunction or activation of arterial endothelium. Low-density lipoprotein (LDL) and especially its oxidized form play a key role in endothelial dysfunction and atherogenesis. Recent studies showed that senescent cells are involved in the development and progression of atherosclerosis, and eliminating senescent cells suppresses the senescence-associated secretory phenotype. We previously reported that molecular hydrogen-rich water (HW) has antioxidant and anti-inflammatory effects in numerous diseases. Here, we used LDL receptor-deficient mice fed a high-fat diet (HFD) for 13 weeks as a model for atherosclerosis and evaluated the effects of continuous administration of HW. The numbers of endothelial cells in the atheroma expressing the senescence factors p16INK4a and p21 decreased in HFD-fed mice given HW compared with HFD-fed mice given control water. Furthermore, macrophage infiltration and Tnfα expression in the atheroma were also suppressed. These results suggest that vascular aging can be suppressed by HW.


Assuntos
Aorta/patologia , Aterosclerose/prevenção & controle , Hidrogênio/administração & dosagem , Animais , Aorta/efeitos dos fármacos , Senescência Celular , Dieta Hiperlipídica , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/patologia , Macrófagos/efeitos dos fármacos , Camundongos , Receptores de LDL/deficiência , Fator de Necrose Tumoral alfa/metabolismo , Água/administração & dosagem , Água/química
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