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1.
Nat Metab ; 5(5): 842-860, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37188818

RESUMO

Different organs undergo distinct transcriptional, epigenetic and physiological alterations that guarantee their functional maturation after birth. However, the roles of epitranscriptomic machineries in these processes have remained elusive. Here we demonstrate that expression of RNA methyltransferase enzymes Mettl3 and Mettl14 gradually declines during postnatal liver development in male mice. Liver-specific Mettl3 deficiency causes hepatocyte hypertrophy, liver injury and growth retardation. Transcriptomic and N6-methyl-adenosine (m6A) profiling identify the neutral sphingomyelinase, Smpd3, as a target of Mettl3. Decreased decay of Smpd3 transcripts due to Mettl3 deficiency results in sphingolipid metabolism rewiring, characterized by toxic ceramide accumulation and leading to mitochondrial damage and elevated endoplasmic reticulum stress. Pharmacological Smpd3 inhibition, Smpd3 knockdown or Sgms1 overexpression that counteracts Smpd3 can ameliorate the abnormality of Mettl3-deficent liver. Our findings demonstrate that Mettl3-N6-methyl-adenosine fine-tunes sphingolipid metabolism, highlighting the pivotal role of an epitranscriptomic machinery in coordination of organ growth and the timing of functional maturation during postnatal liver development.


Assuntos
Fígado , Metiltransferases , Camundongos , Masculino , Animais , Metiltransferases/genética , Metiltransferases/metabolismo , Fígado/metabolismo , Hepatócitos/metabolismo , Ceramidas , Estresse do Retículo Endoplasmático , Adenosina/metabolismo , Esfingomielina Fosfodiesterase/genética , Esfingomielina Fosfodiesterase/metabolismo
2.
Toxins (Basel) ; 14(11)2022 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-36356021

RESUMO

Curcin and Curcin C, both of the ribosome-inactivating proteins of Jatropha curcas, have apparent inhibitory effects on the proliferation of osteosarcoma cell line U20S. However, the inhibitory effect of the latter is 13-fold higher than that of Curcin. The mechanism responsible for the difference has not been studied. This work aimed to understand and verify whether there are differences in entry efficiency and pathway between them using specific endocytosis inhibitors, gene silencing, and labeling techniques such as fluorescein isothiocyanate (FITC) labeling. The study found that the internalization efficiency of Curcin C was twice that of Curcin for U2OS cells. More than one entering pathway was adopted by both of them. Curcin C can enter U2OS cells through clathrin-dependent endocytosis and macropinocytosis, but clathrin-dependent endocytosis was not an option for Curcin. The low-density lipoprotein receptor-related protein 1 (LRP1) was found to mediate clathrin-dependent endocytosis of Curcin C. After LRP1 silencing, there was no significant difference in the 50% inhibitory concentration (IC50) and endocytosis efficiency between Curcin and Curcin C on U2OS cells. These results indicate that LRP1-mediated endocytosis is specific to Curcin C, thus leading to higher U2OS endocytosis efficiency and cytotoxicity than Curcin.


Assuntos
Alcaloides , Jatropha , Osteossarcoma , Toxinas Biológicas , Humanos , Proteínas Inativadoras de Ribossomos Tipo 1/farmacologia , Jatropha/genética , Jatropha/metabolismo , Proteínas Inativadoras de Ribossomos/metabolismo , Toxinas Biológicas/metabolismo , Alcaloides/metabolismo , Clatrina/metabolismo , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo
3.
Int J Biol Macromol ; 195: 433-439, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34896468

RESUMO

Osteosarcoma is a kind of primary bone malignant tumors. Its cure rate has been stagnant in the past decade years. Curcin C belongs to type I ribosome inactivating proteins, extracted from the cotyledons of post-germinated Jatropha curcas seeds. It can inhibit the proliferation of several tumor lines including U2OS cells with extraordinary efficiency. The treated U2OS cells were arrested in both S and G2/M phase, showed typical apoptosis morphological characteristic, formed autophagosomes and increase the ratio of LC3II to LC3I. Meanwhile, the level of ROS in the treated cells was found increasing significantly, with the change of mitochondrial membrane potential and decreased antioxidant enzyme activities. The application of ROS scavenger NAC not only significantly inhibited the toxicity of Curcin C but also prevented the happen of apoptosis and autophagy to some extent. These results suggested that Curcin C may function through ROS pathway. In addition, the Curcin C treatment could activate JNK and inhibit ERK signal pathway. Sp600125, an inhibitor of JNK signaling pathway, can prevent subsequent apoptosis and autophagy events, suggesting that JNK pathway was at least one of the pathways of Curcin C action. Moreover, the relevant including antagonistic among autophagy, apoptosis and cell cycle arresting induced by Curcin C also was found. In summary, it can be speculated that Curcin C may induce S, G2/M phase arrest, apoptosis and autophagy of human osteosarcoma U2OS cells through activating JNK signal pathway and blocking ERK signal pathway by promoting ROS accumulation in cell, thus finally reflected in the effect of inhibiting tumor cell proliferation.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Proteínas Inativadoras de Ribossomos Tipo 1/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Proteínas Inativadoras de Ribossomos Tipo 1/química , Proteínas Inativadoras de Ribossomos Tipo 1/isolamento & purificação
4.
Blood Adv ; 5(20): 4087-4101, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34507351

RESUMO

Primary immune thrombocytopenia (ITP) is an autoantibody-mediated hemorrhagic disorder in which B cells play an essential role. Previous studies have focused on peripheral blood (PB), but B cells in bone marrow (BM) have not been well characterized. We aimed to explore the profile of B-cell subsets and their cytokine environments in the BM of patients with ITP to further clarify the pathogenesis of the disease. B-cell subpopulations and their cytokine/chemokine receptors were detected by using flow cytometry. Plasma concentrations of cytokines/chemokines were measured by using enzyme-linked immunosorbent assay. Messenger RNA levels of B cell-related transcription factors were determined by using quantitative polymerase chain reaction. Regulatory B cell (Breg) function was assessed by quantifying their inhibitory effects on monocytes and T cells in vitro. Decreased proportions of total B cells, naive B cells, and defective Bregs were observed in patients with ITP compared with healthy controls (HCs), whereas an elevated frequency of long-lived plasma cells was found in BM of autoantibody-positive patients. No statistical difference was observed in plasmablasts or in short-lived plasma cells between patients with ITP and HCs. The immunosuppressive capacity of BM Bregs from patients with ITP was considerably weaker than HCs. An in vivo study using an active ITP murine model revealed that Breg transfusion could significantly alleviate thrombocytopenia. Moreover, overactivation of CXCL13-CXCR5 and BAFF/APRIL systems were found in ITP patient BM. Taken together, B-cell subsets in BM were skewed toward a proinflammatory profile in patients with ITP, suggesting the involvement of dysregulated BM B cells in the development of the disease.


Assuntos
Púrpura Trombocitopênica Idiopática , Animais , Linfócitos B , Medula Óssea , Células da Medula Óssea , Humanos , Camundongos , Plasmócitos
5.
J Asian Nat Prod Res ; 23(5): 429-435, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32290693

RESUMO

One new spirocyclic lactone, terreinlactone C (1), and one new benzopyran derivative, 2,2-dimethyl-3-hydroxychroman-6-aldehyde (2), were discovered from the fungus Aspergillus terreus. The chemical structures of compounds 1 and 2 were elucidated by detailedly analyzing NMR and HRESIMS data. Compound 1 is the first natural product with a 1-oxaspiro[4.5]decan-2-one ring system and a possible biogenetic pathway is proposed. Two compounds were tested for their cytotoxic activities against five human cancer cell lines.[Formula: see text].


Assuntos
Benzopiranos , Lactonas , Aspergillus , Benzopiranos/farmacologia , Lactonas/farmacologia , Estrutura Molecular
6.
Int J Infect Dis ; 85: 114-116, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31170547

RESUMO

We report the first case of pulmonary scedosporiosis detected by next-generation sequencing (NGS) from bronchoalveolar lavage fluid (BALF) in a 67-year-old male with bronchiectasis and hematopoietic failure. Scedosporium apiospermum is a ubiquitous organism present in the environment with intrinsic resistance to many antifungal agents. The patient developed respiratory failure, pulmonary consolidation, and septic shock shortly thereafter, and responded poorly to antifungal therapy. This case highlights the combined application of NGS and traditional fungal culture in the clinical diagnosis of pulmonary invasive fungal disease. NGS is proposed as an important adjunctive diagnostic approach for uncommon pathogens.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Infecções Fúngicas Invasivas/diagnóstico , Pneumopatias Fúngicas/diagnóstico , Scedosporium , Idoso , Líquido da Lavagem Broncoalveolar/microbiologia , Hematopoese , Humanos , Infecções Fúngicas Invasivas/complicações , Pneumopatias Fúngicas/complicações , Masculino , Insuficiência Respiratória/etiologia , Choque Séptico/etiologia
7.
Pak J Pharm Sci ; 29(4): 1217-21, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27393434

RESUMO

The protective potential of the methanol extract of Macrothelypteris oligophlebia rhizomes (MMO) for chronic non-bacterial prostatitis (CNP) in rats was investigated in the present study. Carrageenan-induced CNP in rats was established. Fifty rats were randomly divided into sham-operated (sham-ope) group, model group, positive control group (Cernilton at a dose of 148mg/kg body weight) and two MMO-treated groups (MMO at doses of 600mg/kg and 300 mg/kg body weight). The anti-prostatitis effect was evaluated by prostate index, the levels of interleukin-10 (IL-10), tumor necrosis factor alpha (TNF-α), cyclooxygenase-2 (COX-2) and prostaglandin E2 (PGE2), and histopathological examination. After 20 days of administration, MMO could significantly decrease prostate index and the levels of IL-10, TNF-α COX-2 and PGE2 in serum and could improve the prostate morphology in comparison with the model group. In summary, these results suggest that MMO possesses protective effects on prostate, which might be beneficial to further development for the treatment of CNP.


Assuntos
Gleiquênias , Extratos Vegetais/uso terapêutico , Prostatite/tratamento farmacológico , Animais , Doença Crônica , Masculino , Fitoterapia , Ratos , Ratos Sprague-Dawley , Rizoma
8.
Zhongguo Zhong Yao Za Zhi ; 41(3): 396-402, 2016 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-28868853

RESUMO

In order to investigate the epigenetic variations between diploid and autotetraploid of Platycodon grandiflorus. The diploid buds of P. grandiflorus were soaked in the mixture of different concentration colchicines and 0.002 g•mL ⁻¹ dimethyl sulphoxide (DMSO).The identification of autotetraploid plants were based on morphological characteristics, chromosome number and flow cytometry. And then the level and pattern of DNA methylation explored by using the technology of methylation sensitive amplified polymorphism (MSAP).The result demonstrated that the buds soaked in 0.2% colchicines and 0.002 g•mL ⁻¹ DMSO solution for 12 h was ideal conditions to induce autotetraploid of P. grandiflorus, with induction rate of 32.0%.The diploid and tetraploid plants existed distinctly differences in morphological indexes.Totally,1 586 bands were amplified by 20 pairs of selective primers, of which 764 and 822 bands were detected in diploid and autotetraploid respectively. The total methylation ratio,full methylation ratio and hemimethylated ratio were 91.25%,61.25% and 30.65% in diploid of P. grandiflorus,respectively.However,the total methylation ratio,full methylation ratio and hemimethylated ratio of autotetraploid of P. grandiflorus were 86.13%,54.38% and 31.75%, respectively. Compared with diploid, the genomic DNA total methylate ratio and full methylation ratio of autotetration plants decreased by 6.02% and 7.14%.But the hemimethylated ratio of autotetraploid was higher than that of diploid, which more than 1.6%. All this results indicated that DNA methylation patterns have adjusted during the polyploidy process..


Assuntos
Variação Genética , Platycodon/genética , Tetraploidia , Cromossomos de Plantas/genética , Cromossomos de Plantas/metabolismo , Metilação de DNA , DNA de Plantas/genética , Platycodon/classificação , Platycodon/crescimento & desenvolvimento , Platycodon/metabolismo , Polimorfismo Genético
9.
Analyst ; 138(4): 1004-7, 2013 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-23301242

RESUMO

The first "off-on" dual-output fluorescent assay based on reaction-promoted self-assembly approach for glutathione recognition in near infrared region over other relative thiols including cysteine and homocysteine was constructed with high selectivity and large Stocks shift (about 220 nm). The fluorescence enhancement is attributed to the intermolecular interaction, which manipulates the squaraine's aggregates and results in FRET for NIR emission. The sensitivity of the sensing ensemble was further improved in buffer solution containing cationic surfactant.


Assuntos
Ciclobutanos/química , Transferência Ressonante de Energia de Fluorescência/métodos , Glutationa/análise , Fenóis/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Corantes Fluorescentes/química , Glutationa/química
10.
J Med Food ; 15(7): 646-50, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22510101

RESUMO

The present study was conducted to evaluate the effect of a fraction of macroporous resin (FMR), a bioactive component of Smilax china L., on benign prostatic hyperplasia (BPH) in castrated rats induced by testosterone propionate. Rats were randomly divided into five groups: the negative control group (sham-operated), the model group, two FMR-treated groups (at doses of 300 mg/kg and 600 mg/kg of body weight), and the positive control group (treated with finasteride at the dose of 3 mg/kg). Drugs were administered once a day for three consecutive weeks by gastric gavage. Prostates were weighed, testosterone and dihydrotestosterone (DHT) levels in serum were determined, and histopathological examinations were carried out. FMR treatment inhibited prostatic hyperplasia, reducing the DHT level in serum and improving the prostate gland morphology compared with the model group. The overall results of this study suggest that FMR is effective at inhibiting experimentally induced prostate enlargement, and it presents a valuable resource for the treatment of human BPH.


Assuntos
Di-Hidrotestosterona/sangue , Fitoterapia , Extratos Vegetais/uso terapêutico , Próstata/efeitos dos fármacos , Hiperplasia Prostática/tratamento farmacológico , Resinas Vegetais , Smilax , Animais , Castração , Masculino , Extratos Vegetais/farmacologia , Próstata/patologia , Hiperplasia Prostática/sangue , Hiperplasia Prostática/induzido quimicamente , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Rizoma , Propionato de Testosterona
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