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1.
Mol Cell ; 83(16): 3010-3026.e8, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37595559

RESUMO

The mechanistic target of rapamycin complex 1 (mTORC1) is a master regulator of cell growth that stimulates macromolecule synthesis through transcription, RNA processing, and post-translational modification of metabolic enzymes. However, the mechanisms of how mTORC1 orchestrates multiple steps of gene expression programs remain unclear. Here, we identify family with sequence similarity 120A (FAM120A) as a transcription co-activator that couples transcription and splicing of de novo lipid synthesis enzymes downstream of mTORC1-serine/arginine-rich protein kinase 2 (SRPK2) signaling. The mTORC1-activated SRPK2 phosphorylates splicing factor serine/arginine-rich splicing factor 1 (SRSF1), enhancing its binding to FAM120A. FAM120A directly interacts with a lipogenic transcription factor SREBP1 at active promoters, thereby bridging the newly transcribed lipogenic genes from RNA polymerase II to the SRSF1 and U1-70K-containing RNA-splicing machinery. This mTORC1-regulated, multi-protein complex promotes efficient splicing and stability of lipogenic transcripts, resulting in fatty acid synthesis and cancer cell proliferation. These results elucidate FAM120A as a critical transcription co-factor that connects mTORC1-dependent gene regulation programs for anabolic cell growth.


Assuntos
Arginina , Lipogênese , Proteína de Ligação a Elemento Regulador de Esterol 1 , Lipogênese/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Fatores de Processamento de RNA , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Humanos , Proteínas de Ligação a Elemento Regulador de Esterol/metabolismo
2.
J Biol Chem ; 299(9): 105175, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37599001

RESUMO

N6-adenosine methylation (m6A) is the most abundant mRNA modification that controls gene expression through diverse mechanisms. Accordingly, m6A-dependent regulation of oncogenes and tumor suppressors contributes to tumor development. However, the role of m6A-mediated gene regulation upon drug treatment or resistance is poorly understood. Here, we report that m6A modification of mitogen-activated protein kinase 13 (MAPK13) mRNA determines the sensitivity of cancer cells to the mechanistic target of rapamycin complex 1 (mTORC1)-targeting agent rapamycin. mTORC1 induces m6A modification of MAPK13 mRNA at its 3' untranslated region through the methyltransferase-like 3 (METTL3)-METTL14-Wilms' tumor 1-associating protein(WTAP) methyltransferase complex, facilitating its mRNA degradation via an m6A reader protein YTH domain family protein 2. Rapamycin blunts this process and stabilizes MAPK13. On the other hand, genetic or pharmacological inhibition of MAPK13 enhances rapamycin's anticancer effects, which suggests that MAPK13 confers a progrowth signal upon rapamycin treatment, thereby limiting rapamycin efficacy. Together, our data indicate that rapamycin-mediated MAPK13 mRNA stabilization underlies drug resistance, and it should be considered as a promising therapeutic target to sensitize cancer cells to rapamycin.

3.
Environ Res ; : 119437, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38897436

RESUMO

Vertical migration behaviour, which is integral to marine energy circulation, is a prevalent trait among marine organisms. However, the behaviour of phytoplankton, particularly beyond diel vertical migration (DVM), remain underexplored compared to groups like zooplankton. Through the lens of the harmful alga Heterosigma akashiwo, which exhibits unique vertical migrations and fluctuating red tide patterns, this study aimed to explore the ecological intricacies and diverse benefits of phytoplankton vertical migration behaviours. During the bloom period of H. akashiwo, we unexpectedly observed a dense concentration of cells at bottom layer during daytime. This phase coincided with the emergence of cells related to this species' sexual reproduction. Laboratory experiments further showed an elevated frequency of sexual reproduction in the cell populations that migrated to deeper depths compared to those at the surface. This finding implies a connection between dense bottom accumulation (BA) and the life cycle transitions of the species. This BA phase persisted for two days, after which the populations returned to their standard DVM behaviour, providing insight into the unique fluctuating red tide patterns of H. akashiwo. Our study suggests that phytoplankton vertical migrations are not strictly dictated by DVM, revealing diverse vertical migration behaviours that may contribute to the complexity of harmful algal bloom patterns.

4.
BMC Genomics ; 22(1): 231, 2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33794772

RESUMO

BACKGROUND: Commelinaceae (Commelinales) comprise 41 genera and are widely distributed in both the Old and New Worlds, except in Europe. The relationships among genera in this family have been suggested in several morphological and molecular studies. However, it is difficult to explain their relationships due to high morphological variations and low support values. Currently, many researchers have been using complete chloroplast genome data for inferring the evolution of land plants. In this study, we completed 15 new plastid genome sequences of subfamily Commelinoideae using the Mi-seq platform. We utilized genome data to reveal the structural variations and reconstruct the problematic positions of genera for the first time. RESULTS: All examined species of Commelinoideae have three pseudogenes (accD, rpoA, and ycf15), and the former two might be a synapomorphy within Commelinales. Only four species in tribe Commelineae presented IR expansion, which affected duplication of the rpl22 gene. We identified inversions that range from approximately 3 to 15 kb in four taxa (Amischotolype, Belosynapsis, Murdannia, and Streptolirion). The phylogenetic analysis using 77 chloroplast protein-coding genes with maximum parsimony, maximum likelihood, and Bayesian inference suggests that Palisota is most closely related to tribe Commelineae, supported by high support values. This result differs significantly from the current classification of Commelinaceae. Also, we resolved the unclear position of Streptoliriinae and the monophyly of Dichorisandrinae. Among the ten CDS (ndhH, rpoC2, ndhA, rps3, ndhG, ndhD, ccsA, ndhF, matK, and ycf1), which have high nucleotide diversity values (Pi > 0.045) and over 500 bp length, four CDS (ndhH, rpoC2, matK, and ycf1) show that they are congruent with the topology derived from 77 chloroplast protein-coding genes. CONCLUSIONS: In this study, we provide detailed information on the 15 complete plastid genomes of Commelinoideae taxa. We identified characteristic pseudogenes and nucleotide diversity, which can be used to infer the family evolutionary history. Also, further research is needed to revise the position of Palisota in the current classification of Commelinaceae.


Assuntos
Commelinaceae , Genoma de Cloroplastos , Teorema de Bayes , Europa (Continente) , Evolução Molecular , Filogenia
5.
Int J Mol Sci ; 22(23)2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34884886

RESUMO

Heme oxygenase-1 (HO-1) exerts beneficial effects, including angiogenesis and energy metabolism via the peroxisome proliferator-activating receptor-γ coactivator-1α (PGC-1α)-estrogen-related receptor α (ERRα) pathway in astrocytes. However, the role of Korean red ginseng extract (KRGE) in HO-1-mediated mitochondrial function in traumatic brain injury (TBI) is not well-elucidated. We found that HO-1 was upregulated in astrocytes located in peri-injured brain regions after a TBI, following exposure to KRGE. Experiments with pharmacological inhibitors and target-specific siRNAs revealed that HO-1 levels highly correlated with increased AMP-activated protein kinase α (AMPKα) activation, which led to the PGC-1α-ERRα axis-induced increases in mitochondrial functions (detected based on expression of cytochrome c oxidase subunit 2 (MTCO2) and cytochrome c as well as O2 consumption and ATP production). Knockdown of ERRα significantly reduced the p-AMPKα/AMPKα ratio and PGC-1α expression, leading to AMPKα-PGC-1α-ERRα circuit formation. Inactivation of HO by injecting the HO inhibitor Sn(IV) protoporphyrin IX dichloride diminished the expression of p-AMPKα, PGC-1α, ERRα, MTCO2, and cytochrome c in the KRGE-administered peri-injured region of a brain subjected to TBI. These data suggest that KRGE enhanced astrocytic mitochondrial function via a HO-1-mediated AMPKα-PGC-1α-ERRα circuit and consequent oxidative phosphorylation, O2 consumption, and ATP production. This circuit may play an important role in repairing neurovascular function after TBI in the peri-injured region by stimulating astrocytic mitochondrial biogenesis.


Assuntos
Astrócitos/efeitos dos fármacos , Lesões Encefálicas Traumáticas/tratamento farmacológico , Heme Oxigenase-1/metabolismo , Mitocôndrias/metabolismo , Panax , Proteínas Quinases Ativadas por AMP/genética , Animais , Astrócitos/metabolismo , Astrócitos/fisiologia , Lesões Encefálicas Traumáticas/metabolismo , Lesões Encefálicas Traumáticas/fisiopatologia , Citocromos c/metabolismo , Regulação da Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/fisiologia , Biogênese de Organelas , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Receptores de Estrogênio/genética , Receptor ERRalfa Relacionado ao Estrogênio
6.
BMC Genomics ; 21(1): 855, 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-33267775

RESUMO

BACKGROUND: The invasive species Xanthium spinosum has been used as a traditional Chinese medicine for many years. Unfortunately, no extensive molecular studies of this plant have been conducted. RESULTS: Here, the complete chloroplast (cp) genome sequence of X. spinosum was assembled and analyzed. The cp genome of X. spinosum was 152,422 base pairs (bp) in length, with a quadripartite circular structure. The cp genome contained 115 unique genes, including 80 PCGs, 31 tRNA genes, and 4 rRNA genes. Comparative analyses revealed that X. spinosum contains a large number of repeats (999 repeats) and 701 SSRs in its cp genome. Fourteen divergences (Π > 0.03) were found in the intergenic spacer regions. Phylogenetic analyses revealed that Parthenium is a sister clade to both Xanthium and Ambrosia and an early-diverging lineage of subtribe Ambrosiinae, although this finding was supported with a very weak bootstrap value. CONCLUSION: The identified hotspot regions could be used as molecular markers for resolving phylogenetic relationships and species identification in the genus Xanthium.


Assuntos
Genoma de Cloroplastos , Xanthium , Repetições de Microssatélites , Mutação , Filogenia , Xanthium/genética
7.
Clin Immunol ; 211: 108331, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31899330

RESUMO

We aimed to determine the relative contribution of each complement (C3 and C4d) deposition to the progression of IgA nephropathy (IgAN). We enrolled a total of 380 patients with biopsy-confirmed IgAN. Mesangial deposition of C3(<2+ vs. ≥2+) and C4d(positive vs. negative) was evaluated by immunofluorescence staining and immunohistochemistry, respectively. Study endpoint was the composite of a 30% decline in eGFR or ESRD. The risk of reaching the primary outcome was significantly higher in patients having C3 ≥ 2+ and C4d(+) than in corresponding counterparts. Adding C3 deposition to clinical data acquired at kidney biopsy modestly increased the area under the receiver-operating characteristic curve, net reclassification improvement, and integrated discrimination improvement (IDI); adding C4d increased IDI only. In conclusion, mesangial C3 and C4d deposition was an independent risk factor for progression of IgAN. C3 showed better predictability than C4d, suggesting that lectin pathway alone has limited clinical prognostic value.


Assuntos
Complemento C3/imunologia , Complemento C4/imunologia , Glomerulonefrite por IGA/imunologia , Adulto , Feminino , Taxa de Filtração Glomerular , Glomerulonefrite por IGA/patologia , Glomerulonefrite por IGA/fisiopatologia , Humanos , Rim/imunologia , Rim/patologia , Rim/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
8.
Mol Phylogenet Evol ; 148: 106818, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32294543

RESUMO

The families of the monocot order Liliales exhibit highly contrasting characteristic of photosynthetic and mycoheterotrophic life histories. Although previous phylogenetic and morphological studies of Liliales have been conducted, they have not examined molecular evolution associated with this contrasting phenomenon. Here, we conduct the first comparative plastome study of all ten families of Liliales using 29 newly sequenced plastid genomes analyzed together with previously published data. We also present a phylogenetic analysis for Liliales of 78 plastid genes combined with 22 genes from all three genomes (nuclear 18S rDNA and phyC; 17 plastid genes; and mitochondrial matR, atpA, and cob). Within the newly generated phylogenetic tree of Liliales, we evaluate the ancestral state changes of selected morphological traits in the order. There are no significant differences in plastid genome features among species that show divergent characteristics correlated with family circumscriptions. However, the results clearly differentiate between photosynthetic and mycoheterotrophic taxa of Liliales in terms of genome structure, and gene content and order. The newly sequenced plastid genomes and combined three-genome data revealed Smilacaceae as sister to Liliaceae instead of Philesiaceae and Ripogonaceae. Additionally, we propose a revised familial classification system of Liliales that consists of nine families, considering Ripogonaceae a synonym of Philesiaceae. The ancestral state reconstruction indicated synapomorphies for each family of Liliales, except Liliaceae, Melanthiaceae and Colchicaceae. A taxonomic key for all nine families of Liliales is also provided.


Assuntos
Evolução Molecular , Genomas de Plastídeos , Lilium/genética , Sequência de Bases , Teorema de Bayes , DNA de Cloroplastos/genética , Lilium/anatomia & histologia , Fases de Leitura Aberta/genética , Fotossíntese , Filogenia , Especificidade da Espécie
9.
Opt Express ; 28(5): 6734-6739, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32225914

RESUMO

Foveation and (de)focus are two important visual factors in designing near eye displays. Foveation can reduce computational load by lowering display details towards the visual periphery, while focal cues can reduce vergence-accommodation conflict thereby lessening visual discomfort in using near eye displays. We performed two psychophysical experiments to investigate the relationship between foveation and focus cues. The first study measured blur discrimination sensitivity as a function of visual eccentricity, where we found discrimination thresholds significantly lower than previously reported. The second study measured depth discrimination threshold where we found a clear dependency on visual eccentricity. We discuss the study results and suggest further investigation.


Assuntos
Percepção de Profundidade/fisiologia , Percepção Visual/fisiologia , Adulto , Humanos , Pessoa de Meia-Idade , Estimulação Luminosa , Limiar Sensorial , Adulto Jovem
10.
Molecules ; 25(21)2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33114256

RESUMO

Elaeagnus glabra f. oxyphylla (Elaeagnaceae) is a small evergreen tree with narrow lanceolate leaves that is native to Korea. In this work, we studied the chemical composition of E. glabra f. oxyphylla branches (EGFOB) for the first time. Additionally, we evaluated the effects of the ethanol extract of EGFOB and each of its chemical components on key mediators of Alzheimer's disease (AD), namely, amyloid-ß (Aß) aggregation and oxidative stress. The ethanol extract of EGFOB decreased Aß aggregation (IC50 = 32.01 µg/mL) and the levels of the oxidative free radicals 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) (IC50 = 11.35 and 12.32 µg/mL, respectively). Sixteen compounds were isolated from EGFOB. Among them, procyanidin B3 (8), procyanidin B4 (9), and helichrysoside (13) significantly inhibited Aß aggregation (IC50 = 14.59, 32.64, and 44.45 µM, respectively), indicating their potential as bioactive compounds to control Aß aggregation. Furthermore, these compounds markedly enhanced in vitro scavenging activity against ABTS (IC50 = 3.21-4.61 µM). In the DPPH test, they showed lower scavenging activity than in the ABTS test (IC50 ≥ 54.88 µM). Thus, these results suggest that EGFOB and specifically compounds 8, 9, and 13 may be beneficial in AD prevention and treatment through their antioxidant and anti-Aß aggregation activities.


Assuntos
Peptídeos beta-Amiloides/química , Catecóis/química , Elaeagnaceae/química , Flavonoides/química , Flavonoides/farmacologia , Agregados Proteicos/efeitos dos fármacos , Antioxidantes/química , Antioxidantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Folhas de Planta/química
11.
Molecules ; 25(11)2020 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-32503323

RESUMO

The accumulation and formation of advanced glycation end products (AGEs) are related to diabetes and age-related disease. Osteomeles schwerinae C. K. Schneid. (Rosaceae, OSSC) is used traditionally for the treatment of various diseases in Asia. Previous studies have shown that OSSC elicits preventive effects in an in vivo model of diabetes. This study was to evaluate the antiapoptotic effects of dried leaves and twigs of OSSC extract and its major compounds in ARPE-19 cells-spontaneously arising human retinal pigment epithelial cells-under diabetic conditions. To examine the effects of an OSSC extract and its active compounds (acetylvitexin, hyperoside and quercitrin) on apoptosis in methylglyoxal (MG, the active precursor in the formation of AGEs)-treated ARPE-19 cells and the mechanism by which these effects occur, apoptosis was measured using flow cytometry analysis. Protein expression levels of phospho-p53 (p-p53), Bax and Bcl-2 were determined by western blot analyses. The OSSC extract inhibited apoptosis in MG-treated ARPE-19 cells in a dose-dependent manner. The major compounds also reduced the rate of apoptosis. Both the extract and major compounds also inhibited the expression of p-p53 and Bax and increased the levels of Bcl-2 that had been previously reduced by MG treatment. The OSSC extract (0.1 µg/mL) and its major compounds (0.01 µM) attenuated apoptosis in ARPE-19 cells under toxic diabetic conditions by downregulating of expression of p-p53 and Bax. OSSC may serve as an alternative therapy to retard the development of diabetic retinopathy.


Assuntos
Apoptose/efeitos dos fármacos , Extratos Vegetais/farmacologia , Folhas de Planta/química , Aldeído Pirúvico/farmacologia , Epitélio Pigmentado da Retina/efeitos dos fármacos , Rosaceae/química , Proteínas Reguladoras de Apoptose/metabolismo , Humanos , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/patologia , Transdução de Sinais
12.
Mol Pharmacol ; 96(6): 692-701, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31594790

RESUMO

The tetrapeptide Arg-Leu-Tyr-Glu (RLYE), a vascular endothelial growth factor (VEGF) receptor-2 antagonist, has been used previously either alone or in combination with chemotherapeutic drugs for treating colorectal cancer in a mouse model. We analyzed the half-life of the peptide and found that because of degradation by aminopeptidases B and N, it had a short half-life of 1.2 hours in the serum. Therefore, to increase the stability and potency of the peptide, we designed the modified peptide, N-terminally acetylated RLYE (Ac-RLYE), which had a strongly stabilized half-life of 8.8 hours in serum compared with the original parent peptide. The IC50 value of Ac-RLYE for VEGF-A-induced endothelial cell migration decreased to approximately 37.1 pM from 89.1 pM for the parent peptide. Using a mouse xenograft tumor model, we demonstrated that Ac-RLYE was more potent than RLYE in inhibiting tumor angiogenesis and growth, improving vascular integrity and normalization through enhanced endothelial cell junctions and pericyte coverage of the tumor vasculature, and impeding the infiltration of macrophages into tumor and their polarization to the M2 phenotype. Furthermore, combined treatment of Ac-RLYE and irinotecan exhibited synergistic effects on M1-like macrophage activation and apoptosis and growth inhibition of tumor cells. These findings provide evidence that the N-terminal acetylation augments the therapeutic effect of RLYE in solid tumors via inhibition of tumor angiogenesis, improvement of tumor vessel integrity and normalization, and enhancement of the livery and efficacy of the coadministered chemotherapeutic drugs. SIGNIFICANCE STATEMENT: The results of this study demonstrate that the N-terminal acetylation of the tetrapeptide RLYE (Ac-RLYE), a novel vascular endothelial growth factor receptor-2 (VEGFR-2) inhibitor, significantly improves its serum stability, antiangiogenic activity, and vascular normalizing potency, resulting in enhanced therapeutic effect on solid tumors. Furthermore, the combined treatment of Ac-RLYE with the chemotherapeutic drug, irinotecan, synergistically enhanced its antitumor efficacy by improving the perfusion and delivery of the drug into the tumors and stimulating the conversion of the tumor-associated macrophages to an immunostimulatory M1-like antitumor phenotype.


Assuntos
Antineoplásicos/administração & dosagem , Neovascularização Patológica/sangue , Neovascularização Patológica/tratamento farmacológico , Oligopeptídeos/administração & dosagem , Peptídeo Hidrolases/sangue , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Células HCT116 , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Camundongos Nus , Estabilidade Proteica/efeitos dos fármacos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
13.
J Biol Chem ; 293(49): 18989-19000, 2018 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-30279269

RESUMO

Inflammatory cytokines, including tumor necrosis factor-α (TNFα), were elevated in patients with cardiovascular diseases and are also considered as crucial factors in the pathogenesis of preeclampsia; however, the underlying pathogenic mechanism has not been clearly elucidated. This study provides novel evidence that TNFα leads to endothelial dysfunction associated with hypertension and vascular remodeling in preeclampsia through down-regulation of endothelial nitric-oxide synthase (eNOS) by NF-κB-dependent biogenesis of microRNA (miR)-31-5p, which targets eNOS mRNA. In this study, we found that miR-31-5p was up-regulated in sera from patients with preeclampsia and in human endothelial cells treated with TNFα. TNFα-mediated induction of miR-31-5p was blocked by an NF-κB inhibitor and NF-κB p65 knockdown but not by mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase inhibitors, indicating that NF-κB is essential for biogenesis of miR-31-5p. The treatment of human endothelial cells with TNFα or miR-31-5p mimics decreased endothelial nitric-oxide synthase (eNOS) mRNA stability without affecting eNOS promoter activity, resulting in inhibition of eNOS expression and NO/cGMP production through blocking of the functional activity of the eNOS mRNA 3'-UTR. Moreover, TNFα and miR-31-5p mimic evoked endothelial dysfunction associated with defects in angiogenesis, trophoblastic invasion, and vasorelaxation in an ex vivo cultured model of human placental arterial vessels, which are typical features of preeclampsia. These results suggest that NF-κB-responsive miR-31-5p elicits endothelial dysfunction, hypertension, and vascular remodeling via post-transcriptional down-regulation of eNOS and is a molecular risk factor in the pathogenesis and development of preeclampsia.


Assuntos
Células Endoteliais/fisiologia , MicroRNAs/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Pré-Eclâmpsia/metabolismo , Regiões 3' não Traduzidas/genética , Animais , Artérias/efeitos dos fármacos , Regulação para Baixo , Células Endoteliais/efeitos dos fármacos , Feminino , Técnicas de Silenciamento de Genes , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos Endogâmicos C57BL , MicroRNAs/farmacologia , Subunidade p50 de NF-kappa B/genética , Subunidade p50 de NF-kappa B/metabolismo , Neovascularização Fisiológica , Placenta/irrigação sanguínea , Placenta/efeitos dos fármacos , Pré-Eclâmpsia/genética , Gravidez , Trofoblastos/fisiologia , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
14.
J Biol Chem ; 293(38): 14812-14822, 2018 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-30104414

RESUMO

cGMP-dependent protein kinase 1 (PKG1) plays an important role in nitric oxide (NO)/cGMP-mediated maintenance of vascular smooth muscle cell (VSMC) phenotype and vasorelaxation. Inflammatory cytokines, including tumor necrosis factor-α (TNFα), have long been understood to mediate several inflammatory vascular diseases. However, the underlying mechanism of TNFα-dependent inflammatory vascular disease is unclear. Here, we found that TNFα treatment decreased PKG1 expression in cultured VSMCs, which correlated with NF-κB-dependent biogenesis of miR-155-5p that targeted the 3'-UTR of PKG1 mRNA. TNFα induced VSMC phenotypic switching from a contractile to a synthetic state through the down-regulation of VSMC marker genes, suppression of actin polymerization, alteration of cell morphology, and elevation of cell proliferation and migration. All of these events were blocked by treatment with an inhibitor of miR-155-5p or PKG1, whereas transfection with miR-155-5p mimic or PKG1 siRNA promoted phenotypic modulation, similar to the response to TNFα. In addition, TNFα-induced miR-155-5p inhibited the vasorelaxant response of de-endothelialized mouse aortic vessels to 8-Br-cGMP by suppressing phosphorylation of myosin phosphatase and myosin light chain, both of which are downstream signal modulators of PKG1. Moreover, TNFα-induced VSMC phenotypic alteration and vasodilatory dysfunction were blocked by NF-κB inhibition. These results suggest that TNFα impairs NO/cGMP-mediated maintenance of the VSMC contractile phenotype and vascular relaxation by down-regulating PKG1 through NF-κB-dependent biogenesis of miR-155-5p. Thus, the NF-κB/miR-155-5p/PKG1 axis may be crucial in the pathogenesis of inflammatory vascular diseases, such as atherosclerotic intimal hyperplasia and preeclamptic hypertension.


Assuntos
Proteína Quinase Dependente de GMP Cíclico Tipo I/metabolismo , Regulação para Baixo/fisiologia , MicroRNAs/fisiologia , Músculo Liso Vascular/citologia , Fator de Necrose Tumoral alfa/fisiologia , Regiões 3' não Traduzidas , Actinas/metabolismo , Animais , Movimento Celular , Proliferação de Células , Células Cultivadas , Proteína Quinase Dependente de GMP Cíclico Tipo I/genética , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/enzimologia , Músculo Liso Vascular/metabolismo , NF-kappa B/metabolismo , Polimerização , RNA Mensageiro/genética
15.
Drug Metab Dispos ; 47(10): 1183-1194, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31270142

RESUMO

Small interfering RNAs (siRNAs) represent a new class of medicines that are smaller (∼16,000 Da) than biologic therapeutics (>150,000 Da) but much larger than small molecules (<900 Da). Current regulatory guidance on drug-drug interactions (DDIs) from the European Medicines Agency, Food and Drug Administration, and Pharmaceutical and Medical Devices Agency provides no recommendations for oligonucleotide therapeutics including siRNAs; therefore, small molecule guidance documents have historically been applied. Over ∼10 years, in vitro DDI investigations with siRNAs conjugated to a triantennary N-acetylgalactosamine [(GalNAc)-siRNA] ligand have been conducted during nonclinical drug development to elucidate the potential clinical DDI liability. GalNAc siRNAs were evaluated as substrates, inhibitors, or inducers of major cytochrome P450s (P450s) and as substrates and inhibitors of transporters. Aggregate analysis of these data demonstrates a low potential for DDI against P450s. Zero of five, 10, and seven are inducers, time-dependent inhibitors, or substrates, respectively, and nine of 12 do not inhibit any P450 isoform evaluated. Three GalNAc siRNAs inhibited CYP2C8 at supratherapeutic concentrations, and one mildly inhibited CYP2B6. The lowest K i value of 28 µM is >3000-fold above the therapeutic clinical C max at steady state, and importantly no clinical inhibition was projected. Of four GalNAc siRNAs tested none were substrates for transporters and one caused inhibition of P-glycoprotein, calculated not to be clinically relevant. The pharmacological basis for DDIs, including consideration of the target and/or off-target profiles for GalNAc siRNAs, should be made as part of the overall DDI risk assessment. If modulation of the target protein does not interfere with P450s or transporters, then in vitro or clinical investigations into the DDI potential of the GalNAc siRNAs are not warranted. SIGNIFICANCE STATEMENT: Recommendations for evaluating DDI potential of small molecule drugs are well established; however, guidance for novel modalities, particularly oligonucleotide-based therapeutics are lacking. Given the paucity of published data in this field, in vitro DDI investigations are often conducted. The aggregate analysis of GalNAc-siRNA data reviewed herein demonstrates that, like new biological entities, these oligonucleotide-based therapeutic drugs are unlikely to result in DDIs; therefore, it is recommended that the need for in vitro or clinical investigations similarly be determined on a case-by-case basis. Given the mechanism of siRNA action, special consideration should be made in cases where there may be a pharmacological basis for DDIs.


Assuntos
Acetilgalactosamina/farmacologia , Indutores das Enzimas do Citocromo P-450/farmacologia , Inibidores das Enzimas do Citocromo P-450/farmacologia , Oligonucleotídeos/farmacologia , RNA Interferente Pequeno/farmacologia , Acetilgalactosamina/análogos & derivados , Células Cultivadas , Simulação por Computador , Indutores das Enzimas do Citocromo P-450/química , Inibidores das Enzimas do Citocromo P-450/química , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Interações Medicamentosas , Ensaios Enzimáticos , Hepatócitos , Humanos , Concentração Inibidora 50 , Proteínas de Membrana Transportadoras/agonistas , Proteínas de Membrana Transportadoras/genética , Modelos Biológicos , Oligonucleotídeos/química , RNA Interferente Pequeno/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
16.
FASEB J ; 32(8): 4585-4599, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29547704

RESUMO

Regulated in development and DNA damage responses 1 (REDD-1), an inhibitor of mammalian target of rapamycin (mTOR), is induced by various cell stressors, including LPS, a major player in the pathogenesis of endotoxemic shock. However, the pathologic role of REDD-1 in endotoxemia is largely unknown. We found that LPS increased REDD-1 expression, nuclear transcription factor-κB (NF-κB) activation, and inflammation and that these responses were suppressed by REDD-1 knockdown and in REDD-1+/- macrophages. REDD-1 overexpression stimulated NF-κB-dependent inflammation without additional LPS stimulation. REDD-1-induced NF-κB activation was independent of 2 classic IKK-dependent NF-κB pathways and the mTOR signaling pathway; however, REDD-1, particularly its C-terminal region (178-229), interacted with and sequestered IκBα, to elicit atypical NF-κB activation during the delayed and persistent phases of inflammation after stimulation. Moreover, REDD-1 knockdown mitigated vascular inflammation and permeability in endotoxemic mice, resulting in decreases in immune cell infiltration, systemic inflammation, caspase-3 activation, apoptosis, and consequent mortality. We further confirmed the inflammatory and cytotoxic effects of REDD-1 in endotoxemic REDD-1+/- mice. Our data support the likelihood that REDD-1 exacerbates endotoxemic inflammation via atypical NF-κB activation by sequestering IκBα.-Lee, D.-K., Kim, J.-H., Kim, J., Choi, S., Park, M., Park, W., Kim, S., Lee, K.-S., Kim, T., Jung, J., Choi, Y. K., Ha, K.-S., Won, M.-H., Billiar, T. R., Kwon, Y.-G., Kim, Y.-M. REDD-1 aggravates endotoxin-induced inflammation via atypical NF-κB activation.


Assuntos
Endotoxinas/metabolismo , Inflamação/induzido quimicamente , Inflamação/metabolismo , NF-kappa B/metabolismo , Fatores de Transcrição/metabolismo , Animais , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Linhagem Celular , Endotoxemia/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Células Endoteliais da Veia Umbilical Humana , Humanos , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Inibidor de NF-kappaB alfa/metabolismo , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/metabolismo
17.
Mol Biol Rep ; 46(3): 3287-3297, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30980269

RESUMO

Medicinal effects of Crepidiastrum denticulatum have been previously reported. However, the genomic resources of this species and its applications have not been studied. In this study, based on the next generation sequencing method (Miseq sequencing system), we characterize the chloroplast genome of C. denticulatum which contains a large single copy (84,112 bp) and a small single copy (18,519 bp), separated by two inverted repeat regions (25,074 bp). This genome consists of 80 protein-coding gene, 30 tRNAs, and four rRNAs. Notably, the trnT_GGU is pseudogenized because of a small insertion within the coding region. Comparative genomic analysis reveals a high similarity among Asteraceae taxa. However, the junctions between LSC, SSC, and IRs locate in different positions within rps19 and ycf1 among examined species. Also, we describe a newly developed single nucleotide polymorphism (SNP) marker for C. denticulatum based on amplification-refractory mutation system (ARMS) technique. The markers, inferred from SNP in rbcL and matK genes, show effectiveness to recognize C. denticulatum from other related taxa through simple PCR protocol. The chloroplast genome-based molecular markers are effective to distinguish a potentially medicinal species, C. denticulatum, from other related taxa. Additionally, the complete chloroplast genome of C. denticulatum provides initial genomic data for further studies on phylogenomics, population genetics, and evolutionary history of Crepidiastrum as well as other taxa in Asteraceae.


Assuntos
Asteraceae/genética , Cloroplastos/genética , Genoma de Cloroplastos/genética , Biomarcadores , Evolução Molecular , Genes de Plantas/genética , Genoma de Planta/genética , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Plantas Medicinais/genética , Polimorfismo de Nucleotídeo Único/genética , Análise de Sequência de DNA
18.
BMC Musculoskelet Disord ; 20(1): 102, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30841871

RESUMO

BACKGROUND: This meta-analysis was designed to quantify adduction moment loss, to evaluate the relationship between changes in mechanical axis alignment and adduction moment, and to assess whether sagittal plane moment is altered after medial open wedge high tibial osteotomy (HTO). METHODS: Following preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, all studies reporting preoperative and postoperative peak knee adduction moment or change in peak knee adduction moment from before to after surgery in patients who underwent medial open wedge HTO were included. RESULTS: Nine studies were included in the meta-analysis. The pooled mean difference in adduction moment from before to after medial open wedge HTO was 1.44% Nm/body weight (BW)xheight (HT) (95% confidence interval [CI]: 1.33 to 1.55% Nm/BWxHT; P < 0.001; I2 = 4%). However, flexion (0.18% Nm/BWxHT, 95% CI: -0.50 to 0.86% Nm/BWxHT; P = 0.61; I2 = 79%) and extension (0.15% Nm/BWxHT, 95% CI, - 0.37 to 0.68% Nm/BWxHT; P = 0.56; I2 = 46%) moments did not differ significantly from before to after surgery. Alignment correction amount and postoperative final valgus alignment were not significantly associated with difference in adduction moment from before to after surgery. CONCLUSION: Knee adduction moment after medial open wedge HTO decreased to 60% of the preoperative level. However, this adduction moment decrement was not affected by the magnitude of alignment correction. In addition, there was no change in sagittal plane knee moment, including flexion and extension moments, from before to after medial open wedge HTO. LEVEL OF EVIDENCE: Meta-analysis (Level II).


Assuntos
Articulação do Joelho/fisiologia , Osteotomia/tendências , Amplitude de Movimento Articular/fisiologia , Tíbia/cirurgia , Fenômenos Biomecânicos/fisiologia , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Osteotomia/métodos , Estudos Prospectivos , Estudos Retrospectivos , Tíbia/diagnóstico por imagem
19.
J Arthroplasty ; 34(7): 1387-1394, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30930158

RESUMO

BACKGROUND: We previously reported unexpected early failures of total hip arthroplasty (THA) utilizing a 28-mm Ultima metal-on-metal (MoM) articulation. However, long-term results of small-diameter MoM THAs still remain unclear. The purpose of this study was to evaluate the clinical and radiographic outcomes of the previously reported cohort at a minimum follow-up of 15 years. METHODS: The original cohort consisted of 171 primary THAs (167 patients) using a 28-mm MoM articulation performed between April 2000 and March 2002. Of these, 130 hips (126 patients) were reviewed at an average follow-up of 17.1 (range, 15-18) years. Clinical score, complications, presence of osteolytic lesion, serum metal ion concentrations, and implant survivorships were evaluated. RESULTS: The mean Harris Hip Score improved from 44.9 points preoperatively to 90.5 points at the latest follow-up. During the entire period since the original surgery, a total of 5 revisions (3.8%) were associated with adverse reaction to metal debris (ARMD). The last revision surgery for symptomatic ARMD was performed at 6 years postoperatively. The implant survivorships with an end point of revision for aseptic failure and for any reason were 95.4% and 93.8%, respectively. Radiographic osteolytic lesions were detected in 27 hips (20.8%). The average serum metal concentration was 2.50 (range, 0.12-9.86) µg/L for cobalt and 2.81 (range, 0.82-12.3) µg/L for chromium. CONCLUSIONS: THA using a 28-mm MoM articulation showed favorable long-term outcomes with a relatively high revision-free survival rate. There was no significant symptomatic ARMD after the last acetabular revision performed at 6 years postoperatively.


Assuntos
Artroplastia de Quadril/instrumentação , Prótese de Quadril/estatística & dados numéricos , Próteses Articulares Metal-Metal/estatística & dados numéricos , Reoperação/estatística & dados numéricos , Acetábulo/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromo/sangue , Cobalto/sangue , Feminino , Seguimentos , Quadril/cirurgia , Articulação do Quadril/cirurgia , Humanos , Masculino , Metais , Pessoa de Meia-Idade , Desenho de Prótese , Resultado do Tratamento , Adulto Jovem
20.
Int J Mol Sci ; 20(3)2019 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-30691106

RESUMO

Pollution-induced skin damage results in oxidative stress; cellular toxicity; inflammation; and, ultimately, premature skin aging. Previous studies suggest that the activation of autophagy can protect oxidation-induced cellular damage and aging-like changes in skin. In order to develop new anti-pollution ingredients, this study screened various kinds of natural extracts to measure their autophagy activation efficacy in cultured dermal fibroblast. The stimulation of autophagy flux by the selected extracts was further confirmed both by the expression of proteins associated with the autophagy signals and by electron microscope. Crepidiastrum denticulatum (CD) extract treated cells showed the highest autophagic vacuole formation in the non-cytotoxic range. The phosphorylation of adenosine monophosphate kinase (AMPK), but not the inhibition of mammalian target of rapamycin (mTOR), was observed by CD-extract treatment. Its anti-pollution effects were further evaluated with model compounds, benzo[a]pyrene (BaP) and cadmium chloride (CdCl2), and a CD extract treatment resulted in both the protection of cytotoxicity and a reduction of proinflammatory cytokines. These results suggest that the autophagy activators can be a new protection regimen for anti-pollution. Therefore, CD extract can be used for anti-inflammatory and anti-pollution cosmetic ingredients.


Assuntos
Asteraceae/química , Poluentes Ambientais/efeitos adversos , Células Epidérmicas/citologia , Extratos Vegetais/farmacologia , Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia , Benzopirenos/efeitos adversos , Cloreto de Cádmio/efeitos adversos , Células Cultivadas , Citocinas/metabolismo , Células Epidérmicas/efeitos dos fármacos , Células Epidérmicas/metabolismo , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Microscopia Eletrônica de Transmissão , Estresse Oxidativo/efeitos dos fármacos , Fosforilação , Extratos Vegetais/química , Serina-Treonina Quinases TOR/metabolismo
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