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1.
J Am Soc Nephrol ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38857203

RESUMO

BACKGROUND: Chemical modifications on RNA profoundly impact RNA function and regulation. m6A, the most abundant RNA modification in eukaryotes, plays a pivotal role in diverse cellular processes and disease mechanisms. However, its importance is understudied in human chronic kidney disease (CKD) samples regarding its influence on pathological mechanisms. METHODS: LC-MS/MS and Methylated RNA Immunoprecipitation (MeRIP) sequencing were utilized to examine alterations in m6A levels and patterns in CKD samples. Overexpression of the m6A writer METTL3 in cultured kidney tubular cells was performed to confirm the impact of m6A in tubular cells and explore the biological functions of m6A modification on target genes. Additionally, tubule-specific deletion of Mettl3 (Ksp-Cre Mettl3f/f) mice and the use of anti-sense oligonucleotides inhibiting Mettl3 expression were utilized to reduce m6A modification in an animal kidney disease model. RESULTS: By examining 127 human CKD samples, we observed a significant increase in m6A modification and METTL3 expression in diseased kidneys. Epitranscriptomic analysis unveiled an enrichment of m6A modifications in transcripts associated with the activation of inflammatory signaling pathways, particularly the cGAS-STING pathway. m6A hypermethylation increased mRNA stability in cGAS and STING1, as well as elevated the expression of key proteins within the cGAS-STING pathway. Both the tubule-specific deletion of Mettl3 and the use of anti-sense oligonucleotides to inhibit Mettl3 expression protected mice from inflammation, reduced cytokine expression, decreased immune cell recruitment, and attenuated kidney fibrosis. CONCLUSIONS: Our research revealed heightened METTL3-mediated m6A modification in fibrotic kidneys, particularly enriching the cGAS-STING pathway. This hypermethylation increased mRNA stability for cGAS and STING1, leading to sterile inflammation and fibrosis.

2.
J Am Soc Nephrol ; 35(10): 1312-1329, 2024 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-39352860

RESUMO

Background: Chemical modifications on RNA profoundly affect RNA function and regulation. m6A, the most abundant RNA modification in eukaryotes, plays a pivotal role in diverse cellular processes and disease mechanisms. However, its importance is understudied in human CKD samples regarding its influence on pathological mechanisms. Methods: Liquid chromatography­tandem mass spectrometry and methylated RNA immunoprecipitation sequencing were used to examine alterations in m6A levels and patterns in CKD samples. Overexpression of the m6A writer METTL3 in cultured kidney tubular cells was performed to confirm the effect of m6A in tubular cells and explore the biological functions of m6A modification on target genes. In addition, tubule-specific deletion of Mettl3 (Ksp-Cre Mettl3f/f) mice and antisense oligonucleotides inhibiting Mettl3 expression were used to reduce m6A modification in an animal kidney disease model. Results: By examining 127 human CKD samples, we observed a significant increase in m6A modification and METTL3 expression in diseased kidneys. Epitranscriptomic analysis unveiled an enrichment of m6A modifications in transcripts associated with the activation of inflammatory signaling pathways, particularly the cyclic guanosine monophosphate­AMP synthase (cGAS)-stimulator of IFN genes (STING) pathway. m6A hypermethylation increased mRNA stability in cGAS and STING1 as well as elevated the expression of key proteins within the cGAS-STING pathway. Both the tubule-specific deletion of Mettl3 and the use of antisense oligonucleotides to inhibit Mettl3 expression protected mice from inflammation, reduced cytokine expression, decreased immune cell recruitment, and attenuated kidney fibrosis. Conclusions: Our research revealed heightened METTL3-mediated m6A modification in fibrotic kidneys, particularly enriching the cGAS-STING pathway. This hypermethylation increased mRNA stability for cGAS and STING1, leading to sterile inflammation and fibrosis.


Assuntos
Adenosina , Fibrose , Proteínas de Membrana , Metiltransferases , Nucleotidiltransferases , RNA Mensageiro , Nucleotidiltransferases/metabolismo , Nucleotidiltransferases/genética , Adenosina/análogos & derivados , Adenosina/metabolismo , RNA Mensageiro/metabolismo , Animais , Metiltransferases/metabolismo , Metiltransferases/genética , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Humanos , Transdução de Sinais , Camundongos , Rim/patologia , Rim/metabolismo , Nefropatias/genética , Nefropatias/metabolismo , Nefropatias/patologia
3.
J Hum Genet ; 69(9): 433-440, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38866925

RESUMO

BACKGROUND: Intronic GAA repeat expansion ([GAA] ≥250) in FGF14 is associated with the late-onset neurodegenerative disorder, spinocerebellar ataxia 27B (SCA27B, GAA-FGF14 ataxia). We aim to determine the prevalence of the GAA repeat expansion in FGF14 in Chinese populations presenting late-onset cerebellar ataxia (LOCA) and evaluate the characteristics of tandem repeat inheritance, radiological features and sympathetic nerve involvement. METHODS: GAA-FGF14 repeat expansion was screened in an undiagnosed LOCA cohort (n = 664) and variations in repeat-length were analyzed in families of confirmed GAA-FGF14 ataxia patients. Brain magnetic resonance imaging (MRI) was used to evaluate the radiological feature in GAA-FGF14 ataxia patients. Clinical examinations and sympathetic skin response (SSR) recordings in GAA-FGF14 patients (n = 16) were used to quantify sympathetic nerve involvement. RESULTS: Two unrelated probands (2/664) were identified. Genetic screening for GAA-FGF14 repeat expansion was performed in 39 family members, 16 of whom were genetically diagnosed with GAA-FGF14 ataxia. Familial screening revealed expansion of GAA repeats in maternal transmissions, but contraction upon paternal transmission. Brain MRI showed slight to moderate cerebellar atrophy. SSR amplitude was lower in GAA-FGF14 patients in pre-symptomatic stage compared to healthy controls, and further decreased in the symptomatic stage. CONCLUSIONS: GAA-FGF14 ataxia was rare among Chinese LOCA cases. Parental gender appears to affect variability in GAA repeat number between generations. Reduced SSR amplitude is a prominent feature in GAA-FGF14 patients, even in the pre-symptomatic stage.


Assuntos
Fatores de Crescimento de Fibroblastos , Humanos , Masculino , Feminino , Fatores de Crescimento de Fibroblastos/genética , Pessoa de Meia-Idade , Adulto , Imageamento por Ressonância Magnética , Sistema Nervoso Simpático/fisiopatologia , Sistema Nervoso Simpático/patologia , Idoso , Linhagem , Expansão das Repetições de Trinucleotídeos/genética , Sequências de Repetição em Tandem/genética , Degenerações Espinocerebelares
4.
Artigo em Inglês | MEDLINE | ID: mdl-38664060

RESUMO

BACKGROUND AND HYPOTHESIS: Arterial medial calcification (AMC) is a common complication in individuals with chronic kidney disease (CKD), which can lead to cardiovascular morbidity and mortality. The progression of AMC is controlled by a key transcription factor called runt-related transcription factor 2 (RUNX2), which induces vascular smooth muscle cells (VSMCs) transdifferentiation into a osteogenic phenotype. However, RUNX2 has not been targeted for therapy due to its essential role in bone development. The objective of our study was to discover a RUNX2 coactivator that is highly expressed in arterial VSMCs as a potential therapy for AMC. METHODS: We employed transcriptomic analysis of human data and an animal reporter system to pinpoint FHL2 as a potential target. Subsequently, we investigated the mRNA and protein expression patterns of FHL2 in the aortas of both human and animal subjects with CKD. To examine the role of FHL2 in the RUNX2 transcription machinery, we conducted coimmunoprecipitation (Co-IP) and chromatin immunoprecipitation (ChIP) experiments. Next, we manipulated FHL2 expression in cultured VSMCs to examine its impact on high phosphate-induced transdifferentiation. Finally, we employed FHL2 null mice to confirm the role of FHL2 in the development of AMC in vivo. RESULTS: Among all the potential RUNX2 cofactor, FHL2 displays selective expression within the cardiovascular system. In the context of CKD subjects, FHL2 undergoes upregulation and translocation from the cytosol to the nucleus of arterial VSMCs. Once in the nucleus, FHL2 interacts structurally and functionally with RUNX2, acting as a coactivator of RUNX2. Notably, the inhibition of FHL2 expression averts transdifferentiation of VSMCs into an osteogenic phenotype and mitigates aortic calcification in uremic animals, without causing any detrimental effects on the skeletal system. CONCLUSION: These observations provide evidence that FHL2 is a promising target for treating arterial calcification in patients with CKD.

5.
Inflamm Res ; 73(10): 1657-1670, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39052062

RESUMO

OBJECTIVE: Nordalbergin is a coumarin extracted from Dalbergia sissoo DC. To date, the biological effects of nordalbergin have not been well investigated. To investigate the anti-inflammatory responses and the anti-oxidant abilities of nordalbergin using lipopolysaccharide (LPS)-activated macrophages and LPS-induced sepsis mouse model. MATERIALS AND METHODS: Production of nitrite oxide (NO), prostaglandin E2 (PGE2), pro-inflammatory cytokines (tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-1ß), reactive oxygen species (ROS), tissue damage and serum inflammatory markers, and the activation of the NLRP3 inflammasome were examined. RESULTS: Our results indicated that nordalbergin reduced the production of NO and pro-inflammatory cytokines in vitro and ex vivo. Nordalbergin also suppressed iNOS and cyclooxygenase-2 expressions, decreased NF-κB activity, and attenuated MAPKs signaling pathway activation by decreasing JNK and p38 phosphorylation by LPS-activated J774A.1 macrophages. Notably, nordalbergin diminished NLRP3 inflammasome activation via repressing the maturation of IL-1ß and caspase-1 and suppressing ROS production by LPS/ATP- and LPS/nigericin-activated J774A.1 macrophages. Furthermore, nordalbergin exhibited protective effects against the infiltration of inflammatory cells and also inhibited the levels of organ damage markers (AST, ALT, BUN) by LPS-challenged mice. CONCLUSION: Nordalbergin possesses anti-inflammatory effects in macrophage-mediated innate immune responses, alleviates ROS production, decreases NLRP3 activation, and exhibits protective effects against LPS-induced tissue damage in mice.


Assuntos
Endotoxemia , Inflamassomos , Lipopolissacarídeos , NF-kappa B , Proteína 3 que Contém Domínio de Pirina da Família NLR , Espécies Reativas de Oxigênio , Animais , Espécies Reativas de Oxigênio/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Camundongos , NF-kappa B/metabolismo , Masculino , Endotoxemia/induzido quimicamente , Endotoxemia/tratamento farmacológico , Inflamassomos/efeitos dos fármacos , Inflamassomos/metabolismo , Camundongos Endogâmicos C57BL , Citocinas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Cumarínicos/farmacologia , Cumarínicos/uso terapêutico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Linhagem Celular , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Óxido Nítrico/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos
6.
Inorg Chem ; 63(15): 6734-6742, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38570330

RESUMO

The design of multimetal catalysts holds immense significance for efficient CO2 capture and its conversion into economically valuable chemicals. Herein, heterobimetallic catalysts (MiMo)L were exploited for the CO2 reduction reactions (CO2RR) using relativistic density functional theory (DFT). The octadentate Pacman-like polypyrrolic ligand (H4L) accommodates two metal ions (Mo, W, Nd, and U) inside (Mi) and outside (Mo) its month, rendering a weak bimetal coupling-assisted MN4 catalytically active site. Adsorption reactions have access to energetically stable coordination modes of -OCO, -OOC, and -(OCO)2, where the donor atom(s) are marked in bold. Among all of the species, (UiMoo)L releases the most energy. Along CO2RR, it favors to produce CO. The high-efficiency CO2 reduction is attributed to the size matching of U with the ligand mouth and the effective manipulation of the electron density of both ligand and bimetals. The mechanism in which heterobimetals synergetically capture and reduce CO2 has been postulated. This establishes a reference in elaborating on the complicated heterogeneous catalysis.

7.
Sensors (Basel) ; 24(11)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38894273

RESUMO

In this paper, we present a high-precision optical frequency noise detection and comparison technique using a two-way transfer method over a 260 km field fiber link. This method allows for the comparison of optical frequencies between remote optical references without the need for data transfer through communication. We extend a previously established two-way comparison technique to obtain all data at the local site. Two optical carrier signals are injected into the bidirectional fiber from both ends, and one carrier is reflected back from the remote end. This enables the phase comparison of the two carrier signals at a single site without the need to transmit experimental data. The common-mode frequency noise induced by the bidirectional fiber link is detected and effectively suppressed without the need for sophisticated active fiber noise control. Our demonstration system, which uses a 260 km field fiber link and a common laser source, achieves a fractional instability of 2.5×10-17 at 1 s averaging time and scales down to 3.5×10-21 at 8000 s. This scheme offers the distinct advantage of completing the comparison at a single site, eliminating the need for remote data transfer via communication. This method is expected to enhance reliability for high-precision frequency comparisons between remote optical clocks and advanced atomic clocks.

8.
Mov Disord ; 38(9): 1750-1755, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37394769

RESUMO

OBJECTIVES: To diagnose the molecular cause of hereditary spastic paraplegia (HSP) observed in a four-generation family with autosomal dominant inheritance. METHODS: Multiplex ligation-dependent probe amplification (MLPA), whole-exome sequencing (WES), and RNA sequencing (RNA-seq) of peripheral blood leukocytes were performed. Reverse transcription polymerase chain reaction (RT-PCR) and Sanger sequencing were used to characterize target regions of SPAST. RESULTS: A 121-bp AluYb9 insertion with a 30-bp poly-A tail flanked by 15-bp direct repeats on both sides was identified in the edge of intron 16 in SPAST that segregated with the disease phenotype. CONCLUSIONS: We identified an intronic AluYb9 insertion inducing splicing alteration in SPAST causing pure HSP phenotype that was not detected by routine WES analysis. Our findings suggest RNA-seq is a recommended implementation for undiagnosed cases by first-line diagnostic approaches. © 2023 International Parkinson and Movement Disorder Society.


Assuntos
Paraplegia Espástica Hereditária , Humanos , Paraplegia Espástica Hereditária/genética , Paraplegia Espástica Hereditária/diagnóstico , Espastina/genética , Adenosina Trifosfatases/genética , Fenótipo , Íntrons/genética , Mutação
9.
Inorg Chem ; 62(27): 10762-10771, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37377386

RESUMO

The successful management and safe disposal of high-level nuclear waste necessitate the efficient separation of actinides (An) from lanthanides (Ln), which has emerged as a crucial prerequisite. Mixed donor ligands incorporating both soft and hard donor atoms have garnered interest in the field of An/Ln separation and purification. One such example is nitrilotriacetamide (NTAamide) derivatives, which have demonstrated selectivity in extracting minor actinide Am(III) ions over Eu(III) ions. Nevertheless, the Am/Eu complexation behavior and selectivity remain underexplored. In the work, a comprehensive and systematic investigation has been conducted for [M(RL)(NO3)3] complexes (M = Am and Eu) utilizing relativistic density functional theory. The NTAamide ligand (RL) is substituted with various alkyl groups, namely, methyl, ethyl, propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, and n-octyl. Thermodynamic calculations show that the alkyl chain length in NTAamide is capable of tuning the separation selectivity of Am and Eu. Moreover, the differences in calculated free energies between Am and Eu complexes are more negative for R = Bu-Oct than Me-Pr. This indicates that elongation of the alkyl chain can increase the efficiency of selective separation of Am(III) from Eu(III). Based on the quantum theory of atoms in molecules and charge decomposition analyses, it has been observed that the strength of Am-RL bonds is higher than that of Eu-RL bonds. This disparity is attributed to a greater degree of covalency in Am-RL bonds and a higher level of charge transfer from ligands to Am within complexes containing these bonds. Energies of occupied orbitals with the central N character are recognized overall lower for [Am(OctL)(NO3)3] than for [Eu(OctL)(NO3)3], indicative of stronger complexation stability of the former. These results offer valuable insights into the separation mechanism of NTAamide ligands, which can help guide the development of more powerful agents for An/Ln separation in future applications.

10.
Cell Mol Biol (Noisy-le-grand) ; 69(12): 118-123, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38063108

RESUMO

Thyroid cancer (TC) originates from thyroid epithelial cells and is one of the common malignant tumors in the endocrine system. The aim of our study was to explore the dynamic changes of serum miR-105-3p expression after TC surgery and its correlation with clinicopathological manifestations, and evaluate its clinical value as a potential biomarker after surgery. A total of 100 TC patients were selected as the research objects. To detect serum miR-105-3p in patients and its correlation with tumor pathological characteristics and the dynamic changes of postoperative serum miR-105-3p in patients to evaluate its prognostic value as a potential biomarker. Serum miR-105-3p increases in patients with well-differentiated TC and lymph node metastasis; Serum miR-105-3p gradually decreases after surgery, and there is a significant difference between 4 days after surgery and before surgery,  serum miR-105-3p level can significantly distinguish between patients with poor prognosis and good prognosis within 2 years after the operation, and it can predict the improvement of the prognosis of TC after surgery. The level of serum miR-105-3p is closely related to tumor differentiation and lymph node metastasis in TC patients. Its level gradually decreases with the passage of time after surgery. It has a good diagnostic value for the prognosis of TC after surgery and is expected to become a TC surgery. Potential biomarkers for post-diagnosis.


Assuntos
MicroRNAs , Neoplasias da Glândula Tireoide , Humanos , Metástase Linfática , Prognóstico , MicroRNAs/metabolismo , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/cirurgia , Biomarcadores , Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica
11.
J Invertebr Pathol ; 201: 108013, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37923117

RESUMO

Infectious hypodermal and hematopoietic necrosis virus (IHHNV) is one of the linearly single-stranded DNA viruses. Ecytonucleospora hepatopenaei (EHP) is an intracellular parasitic microsporidian. IHHNV and EHP are pathogens that have been widely prevalent in shrimp farming. Both of them are associated with growth retardation of the penaeid shrimp, which causes serious economic losses to shrimp farming. Shrimp can be co-infected with IHHNV and EHP. In this study, a rapid duplex polymerase chain reaction (PCR) was developed and optimized for the simultaneous detection of EHP and IHHNV. The detection limit of the duplex PCR could reach 1.5 × 102 copies for EHP and IHHNV. A total of 578 Litopenaeus vannamei samples were detected by the established duplex PCR detection method. The results suggested that 398 samples were infected with EHP, 362 samples were infected with IHHNV, and 265 samples were co-infected with EHP and IHHNV. The case-control analysis of the detected shrimp samples showed a certain synergistic effect between EHP and IHHNV.


Assuntos
Densovirinae , Microsporídios , Penaeidae , Animais , Densovirinae/genética , Reação em Cadeia da Polimerase/métodos , Agricultura , Microsporídios/genética
12.
Chem Biodivers ; 20(2): e202201111, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36546830

RESUMO

Leptosperols C-G (1-5), five new phenylpropanoyl phloroglucinol derivatives were isolated from the leaves of Leptospermum scoparium. Compounds 1-3 are phenylpropanoyl phloroglucinol-sesquiterpene adducts with new carbon skeletons. Their structures with absolute configurations were elucidated by detailed spectroscopic analyses, single-crystal X-ray diffraction, and electronic circular dichroism (ECD) calculation. Compounds 2 and 3 exhibited moderate anti-inflammatory activity in zebrafish acute inflammatory models.


Assuntos
Leptospermum , Floroglucinol , Animais , Leptospermum/química , Estrutura Molecular , Floroglucinol/química , Peixe-Zebra , Cristalografia por Raios X
13.
Int J Mol Sci ; 24(2)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36675089

RESUMO

Active packaging materials protect food from deterioration and extend its shelf life. In the quest to design intriguing packaging materials, biocomposite ZnO/plant polyphenols/cellulose/polyvinyl alcohol (ZnPCP) was prepared via simple hydrothermal and casting methods. The structure and morphology of the composite were fully analyzed using XRD, FTIR, SEM and XPS. The ZnO particles, plant polyphenols (PPL) and cellulose were found to be dispersed in PVA. All of these components share their unique functions with the composite's properties. This study shows that PPL in the composite not only improves the ZnO dispersivity in PVA as a crosslinker, but also enhances the water barrier of PVA. The ZnO, PPL and cellulose work together, enabling the biocomposite to perform as a good food packaging material with only a 1% dosage of the three components in PVA. The light shielding investigation showed that ZnPCP-10 can block almost 100% of both UV and visible light. The antibacterial activities were evaluated by Gram-negative Escherichia coli (E. coli) and Gram-positive staphylococcus aureus (S. aureus), with 4.4 and 6.3 mm inhibition zones, respectively, being achieved by ZnPCP-10. The enhanced performance and easy degradation enables the biocomposite ZnPCP to be a prospect material in the packaging industry.


Assuntos
Quitosana , Óxido de Zinco , Embalagem de Alimentos , Álcool de Polivinil/química , Celulose/química , Óxido de Zinco/química , Quitosana/química , Staphylococcus aureus , Escherichia coli , Antibacterianos/farmacologia , Antibacterianos/química
14.
Int J Mol Sci ; 24(8)2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37108458

RESUMO

Microglia-associated neuroinflammation is recognized as a critical factor in the pathogenesis of neurodegenerative diseases; however, there is no effective treatment for the blockage of neurodegenerative disease progression. In this study, the effect of nordalbergin, a coumarin isolated from the wood bark of Dalbergia sissoo, on lipopolysaccharide (LPS)-induced inflammatory responses was investigated using murine microglial BV2 cells. Cell viability was assessed using the MTT assay, whereas nitric oxide (NO) production was analyzed using the Griess reagent. Secretion of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) was detected by the ELISA. The expression of inducible NO synthase (iNOS), cyclooxygenase (COX)-2, mitogen-activated protein kinases (MAPKs) and NLRP3 inflammasome-related proteins was assessed by Western blot. The production of mitochondrial reactive oxygen species (ROS) and intracellular ROS was detected using flow cytometry. Our experimental results indicated that nordalbergin ≤20 µM suppressed NO, IL-6, TNF-α and IL-1ß production; decreased iNOS and COX-2 expression; inhibited MAPKs activation; attenuated NLRP3 inflammasome activation; and reduced both intracellular and mitochondrial ROS production by LPS-stimulated BV2 cells in a dose-dependent manner. These results demonstrate that nordalbergin exhibits anti-inflammatory and anti-oxidative activities through inhibiting MAPK signaling pathway, NLRP3 inflammasome activation and ROS production, suggesting that nordalbergin might have the potential to inhibit neurodegenerative disease progression.


Assuntos
Lipopolissacarídeos , Doenças Neurodegenerativas , Camundongos , Animais , Lipopolissacarídeos/farmacologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Inflamassomos/metabolismo , Microglia/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Doenças Neuroinflamatórias , Interleucina-6/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Doenças Neurodegenerativas/metabolismo , Transdução de Sinais , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo
15.
Arch Microbiol ; 204(3): 176, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35166931

RESUMO

Two extremely halophilic strains, designated SYSU A558-1T and SYSU A121-1, were isolated from a saline sediment sample collected from Aiding salt-lake, China. Cells of strains SYSU A558-1T and SYSU A121-1 were Gram-stain-negative, coccoid, and non-motile. The strains were aerobic and grew at NaCl concentration of 10-30% (optimum, 20-22%), at 20-55 °C (optimum, 37-42 °C) and at pH 6.5-8.5 (optimum, 7.0-8.0). Cells lysed in distilled water. The polar lipids were phosphatidyl choline, phosphatidylglycerol phosphate methyl ester, disulfated diglycosyl diether-1 and unidentified glycolipid. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that the two strains SYSU A558-1T and SYSU A121-1 were closely related to the membranes of the genus Haloterrigena. Phylogenetic and phylogenomic trees of strains SYSU A558-1T and SYSU A121-1 demonstrated a robust clade with Haloterrigena turkmenica, Haloterrigena salifodinae and Haloterrigena salina. The genomic DNA G + C content of strains SYSU A558-1T and SYSU A121-1 were 65.8 and 65.0%, respectively. Phenotypic, phylogenetic, chemotaxonomic and genome analysis suggested that the two strains SYSU A558-1T and SYSU A121-1 represent a novel species of the genus Haloterrigena, for which the name Haloterrigena gelatinilytica sp. nov. is proposed. The type strain is SYSU A558-1T (= KCTC 4259T = CGMCC 1.15953T).


Assuntos
Halobacteriaceae , Lagos , China , DNA Arqueal/genética , Halobacteriaceae/genética , Fosfolipídeos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Cloreto de Sódio
16.
Arch Microbiol ; 204(8): 475, 2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35829834

RESUMO

A Gram-negative, aerobic, chemoheterotrophic, rod-shaped, and motile bacterium, designated as LST-1T, was isolated from wild Stevia rebaudiana Bertoni and subjected to a polyphasic taxonomic analysis. The LST-1 strain grew optimally at 37 °C and pH 6.0-7.0 in the presence of 0.5% (w/v) NaCl. Phylogenetic analysis based on the 16S rDNA sequence indicated that LST-1 is closely related to Lelliottia jeotgali PFL01T (99.85%), Lelliottia nimipressuralis LMG10245T (98.82%), and Lelliottia amnigena LMG2784T (98.54%). Multi-locus sequence typing of concatenated partial atpD, infB, gyrB, and rpoB genes was performed to improve the resolution, and clear distinctions between the closest related type strains were observed. The results of average nucleotide identify analyses and DNA-DNA hybridization with four species (16S rDNA similarity > 98.65%) were less than 90 and 40%, respectively, verifying the distinct characteristics from other species of Lelliottia. The cellular fatty acid profile of the strain consisted of C16:0, Summed Feature3, and Summed Feature8 (possibly 16:1 w6c/16:1 w7c and 18:1 w6c) as major components. The major polar lipids included phosphatidylethanolamine, phosphatidylglycerol, an aminophospholipid, three non-characteristic phospholipids, and a non-characteristic lipid. The genome of LST-1T was 4,611,055 bp in size, with a G + C content of 55.02%. The unique combination of several phenotypic, chemotaxonomic, and genomic characteristics proved that strain LST-1T belongs to a novel species, for which the name Lelliottia steviae sp. nov. is proposed. The type strain is LST-1T (= CGMCC 1.19175T = JCM 34938T).Repositories: The genbank accession numbers for the 16S rRNA gene and genome sequences of strain LST-1T are MZ497264 and CP063663, respectively.


Assuntos
Stevia , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , DNA Ribossômico , Ácidos Graxos/análise , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Stevia/genética
17.
Fish Shellfish Immunol ; 121: 1-11, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34974153

RESUMO

Mitogen-activated protein kinase kinases (MKKs) are intermediate kinases of mitogen-activated protein kinases (MAPKs) signaling pathways. MKKs are activated by mitogen-activated protein kinase kinase kinase (MKKK) and then the activated MKKs trigger the activation of downstream MAPKs. MAPK signaling pathways play an important role in regulating immune functions including apoptosis and inflammation. However, studies on identification and characterization of mkk repertoire in rainbow trout (Oncorhynchus mykiss) are still limited. Trout experienced 4 rounds (4R) of whole genome duplication (WGD), thus exhibiting increased paralogs of mkks with potentially functional diversity. In this study, we identified 17 mkk genes in trout and the following bacterial challenge (Vibrio anguillarum) studies showed functional diversity of different mkk subtypes. Vibrio anguillarum infection resulted in significantly up-regulated mkk2 subtypes in spleen and liver, and mkk4b3 in spleen, suggesting immunomodulation was regulated by activation of ERK, p38 and JNK pathways. Compared to other mkk subtypes, mkk6s were down-regulated in symptomatic group, rather than asymptomatic group. The organisms present negative feedback on MAPK activation, thus reducing extra damage to cells. We observed down-regulated mkk6s with up-regulated genes (dusp1 & dusp2) involved in negative feedback of MAPK activation. Based on these results, we might propose the distinct expression patterns of genes associated with MAPK pathways resulted in different phenotypes and symptoms of trout in response to bacterial challenge.


Assuntos
Proteínas de Peixes , Quinases de Proteína Quinase Ativadas por Mitógeno , Oncorhynchus mykiss , Vibrioses , Animais , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Oncorhynchus mykiss/genética , Oncorhynchus mykiss/metabolismo , Vibrio , Vibrioses/veterinária
18.
Molecules ; 27(18)2022 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-36144824

RESUMO

Transition metal oxides (TMOs) and actinide ones (AnOs) have been widely applied in catalytic reactions due to their excellent physicochemical properties. However, the reaction pathway and mechanism, especially involving TM-An heterometallic centers, remain underexplored. In this respect, relativistic density functional theory (DFT) was used to examine uranium-doped zinc, copper, and nickel oxides for their catalytic activity toward the conversion of furfural to furfuryl alcohol. A comparison was made with their undoped TMOs. It was found that the three TMOs were capable of catalyzing the reaction, where the free energies of adsorption, hydrogenation, and desorption fell between -33.93 and 45.00 kJ/mol. The uranium doping extremely strengthened the adsorption of CuO-U and NiO-U toward furfural, making hydrogenation or desorption much harder. Intriguingly, ZnO-U showed the best catalytic performance among all six catalyst candidates, as its three reaction energies were very small (-10.54-8.12 kJ/mol). The reaction process and mechanism were further addressed in terms of the geometrical, bonding, charge, and electronic properties.

19.
Cancer Cell Int ; 21(1): 584, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34717645

RESUMO

BACKGROUND: Hypopharyngeal cancer (HPC) is associated with a poor prognosis and a high recurrence rate. Immune escape is one of the reasons for the poor prognosis of malignant tumors. Programmed cell death ligand 1 (PD-L1) and programmed cell death-1 (PD-1) have been shown to play important roles in immune escape. However, the role of PD-1/PD-L1 in HPC remains unclear. In this experiment, we investigated the effect of exosomes from HPC patient serum on CD8+ T cell function and PD-1/PD-L1 expression and, thus, on prognosis. We hope to provide guidance for the identification of new targets for HPC immunotherapy. METHODS: PD-1 and CD8 expression in 71 HPC tissues and 16 paracarcinoma tissues was detected by immunohistochemistry. Concurrently, the clinicopathological data of the patients were obtained to conduct correlation analysis. Exosomes were isolated from serum and then identified by Western blotting (WB), transmission electron microscopy (TEM), and nanoparticle tracking analysis (NTA). Flow cytometry was used to assess the activity of CD8+ T cells after exosome stimulation. The effects of exosomes on the ability of CD8+ T cells to kill FaDu cells were assessed by CCK-8 assay. The expression of IL-10 and TGF-ß1 was measured by enzyme-linked immunosorbent assay (ELISA). PD-L1 expression in HPC tissue samples was evaluated by immunohistochemistry, and the relationship between PD-1/PD-L1 expression and prognosis was investigated with patient specimens. RESULTS: PD-1 expression was significantly upregulated on CD8+ T cells in tumor tissues compared with those in normal tissues. The overall survival (OS) and disease-free survival (DFS) of PD-1-overexpressing patients were decreased. Serum exosomes from patients can elevate PD-1 expression on CD8+ T cells and suppress their killing capacity and secretory function. The rate of positive PD-L1 expression was increased in HPC tissues compared with paracancerous tissues. The DFS and OS of the PD-1(+)-PD-L1(+) group were significantly lower than those of the PD-1(-)-PD-L1(-) group. CONCLUSION: Our findings indicate that serum exosomes from HPC patients can inhibit CD8+ T cell function and that the PD-1-PD-L1 pathway plays an important role in the immune escape of HPC. Exosomes combined with immunotherapy may guide the treatment of patients with advanced disease in the future.

20.
Bioorg Chem ; 107: 104624, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33465669

RESUMO

Two novel monoterpenoid indole alkaloids (MIAs), gelsechizines A-B (1-2), along with four known ones (3-6) were isolated from the fruits of Gelsemium elegans. Compound 1 features a new carbon skeleton with two additional carbon atoms forming a 4-methylpyridine unit. Their structures with absolute configurations were elucidated by NMR, MS, X-ray diffraction and electronic circular dichroism (ECD) calculations. Compounds 1-3 showed significant anti-inflammatory effects in vivo and in vitro, which may be related to the inhibition of the trecruitment of neutrophils and macrophages as well as the secretion of TNF-α and IL-6. Preliminary structure-activity relationship analysis revealed that the ß-N-acrylate moiety plays an important role in the anti-inflammatory effect.


Assuntos
Anti-Inflamatórios/farmacologia , Gelsemium/química , Macrófagos/efeitos dos fármacos , Alcaloides de Triptamina e Secologanina/química , Animais , Animais Geneticamente Modificados/crescimento & desenvolvimento , Animais Geneticamente Modificados/metabolismo , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Frutas/química , Frutas/metabolismo , Gelsemium/metabolismo , Interleucina-6/metabolismo , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/citologia , Macrófagos/metabolismo , Espectroscopia de Ressonância Magnética , Camundongos , Conformação Molecular , Neutrófilos/citologia , Neutrófilos/patologia , Células RAW 264.7 , Alcaloides de Triptamina e Secologanina/isolamento & purificação , Alcaloides de Triptamina e Secologanina/farmacologia , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/metabolismo , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/metabolismo
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