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1.
Plant Cell ; 35(4): 1241-1258, 2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-36648110

RESUMO

In Arabidopsis thaliana, female gametophyte (FG) development is accompanied by the formation and expansion of the large vacuole in the FG; this is essential for FG expansion, nuclear polar localization, and cell fate determination. Arabidopsis VACUOLELESS GAMETOPHYTES (VLG) facilitates vesicular fusion to form large vacuole in the FG, but the regulation of VLG remains largely unknown. Here, we found that gain-of-function mutation of BRASSINOSTEROID INSENSITIVE2 (BIN2) (bin2-1) increases VLG abundance to induce the vacuole formation at stage FG1, and leads to abortion of FG. Loss-of-function mutation of BIN2 and its homologs (bin2-3 bil1 bil2) reduced VLG abundance and mimicked vlg/VLG phenotypes. Knocking down VLG in bin2-1 decreased the ratio of aberrant vacuole formation at stage FG1, whereas FG1-specific overexpression of VLG mimicked the bin2-1 phenotype. VLG partially rescued the bin2-3 bil1 bil2 phenotype, demonstrating that VLG acts downstream of BIN2. Mutation of VLG residues that are phosphorylated by BIN2 altered VLG stability and a phosphorylation mimic of VLG causes similar defects as did bin2-1. Therefore, BIN2 may function by interacting with and phosphorylating VLG in the FG to enhance its stability and abundance, thus facilitating vacuole formation. Our findings provide mechanistic insight into how the BIN2-VLG module regulates the spatiotemporal formation of the large vacuole in FG development.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/fisiologia , Proteínas de Arabidopsis/metabolismo , Brassinosteroides/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Células Germinativas Vegetais/metabolismo , Óvulo Vegetal/genética , Óvulo Vegetal/metabolismo , Fosforilação , Proteínas Quinases/metabolismo , Transdução de Sinais/genética , Vacúolos/metabolismo
2.
PLoS Genet ; 18(3): e1010077, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35245283

RESUMO

Ovule initiation determines the maximum ovule number and has great impact on seed number and yield. However, the regulation of ovule initiation remains largely elusive. We previously reported that most of the ovule primordia initiate asynchronously at floral stage 9 and PINFORMED1 (PIN1) polarization and auxin distribution contributed to this process. Here, we further demonstrate that a small amount of ovule primordia initiate at floral stage 10 when the existing ovules initiated at floral stage 9 start to differentiate. Genetic analysis revealed that the absence of PIN3 function leads to the reduction in pistil size and the lack of late-initiated ovules, suggesting PIN3 promotes the late ovule initiation process and pistil growth. Physiological analysis illustrated that, unlike picloram, exogenous application of NAA can't restore these defective phenotypes, implying that PIN3-mediated polar auxin transport is required for the late ovule initiation and pistil length. qRT-PCR results indicated that the expression of SEEDSTICK (STK) is up-regulated under auxin analogues treatment while is down-regulated in pin3 mutants. Meanwhile, overexpressing STK rescues pin3 phenotypes, suggesting STK participates in PIN3-mediated late ovule initiation possibly by promoting pistil growth. Furthermore, brassinosteroid influences the late ovule initiation through positively regulating PIN3 expression. Collectively, this study demonstrates that PIN3 promotes the late ovule initiation and contributes to the extra ovule number. Our results give important clues for increasing seed number and yield of cruciferous and leguminous crops.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Proteínas de Domínio MADS/genética , Óvulo Vegetal/genética
3.
J Intensive Care Med ; : 8850666241253162, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748540

RESUMO

OBJECTIVES: The study investigated whether percutaneous partial pressure of oxygen (PtcO2), percutaneous partial pressure of carbon dioxide (PtcCO2), and the derived tissue perfusion index (TPI) can predict the severity and short-term outcomes of severe and critical COVID-19. DESIGN: Prospective observational study conducted from January 1, 2023 to February 10, 2023. SETTING: A teaching hospital specializing in tertiary care in Nanjing City, Jiangsu Province, China. PARTICIPANTS: Adults (≥18 years) with severe and critical COVID-19. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The general information and vital signs of the patients were collected. The PtcO2 and PtcCO2 were monitored in the left dorsal volar. The ratio of TPI was defined as the ratio of PtcO2/fraction of inspired oxygen (FiO2) to PtcCO2. Mortality at 28 was recorded. The ability of the TPI to assess disease severity and predict prognosis was determined. ENDPOINT: Severity of the disease on the enrollment and mortality at 28. RESULTS: A total of 71 patients with severe and critical COVID-19, including 40 severe and 31 critical cases, according to the COVID-19 treatment guidelines published by WHO, were recruited. Their median age was 70 years, with 56 (79%) males. The median SpO2/FiO2, PtcO2, PtcCO2, PtcO2/ FiO2, and TPI values were 237, 61, 42, 143, and 3.6 mm Hg, respectively. Compared with those for severe COVID-19, the TPI, PtcO2/ FiO2, SpO2/FiO2, and PtcO2 were significantly lower in critical COVID-19, while the PtcCO2 was significantly higher. After 28 days, 26 (37%) patients had died. TPI values < 3.5 were correlated with more severe disease status (AUC 0.914; 95% CI: 0.847-0.981, P < 0.001), and TPI < 3.3 was associated with poor outcomes (AUC 0.937; 95% CI 0.880-0.994, P < 0.001). CONCLUSIONS: The tissue perfusion index (TPI), PtcCO2, and PtcO2/ FiO2 can predict the severity and outcome of severe and critical COVID-19.

4.
Development ; 147(24)2020 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-33234714

RESUMO

Plant ovule initiation determines the maximum of ovule number and has a great impact on the seed number per fruit. The detailed processes of ovule initiation have not been accurately described, although two connected processes, gynoecium and ovule development, have been investigated. Here, we report that ovules initiate asynchronously. The first group of ovule primordia grows out, the placenta elongates, the boundaries of existing ovules enlarge and a new group of primordia initiates from the boundaries. The expression pattern of different marker genes during ovule development illustrates that this asynchronicity continues throughout whole ovule development. PIN-FORMED1 polar distribution and auxin response maxima correlate with ovule primordia asynchronous initiation. We have established computational modeling to show how auxin dynamics influence ovule primordia initiation. Brassinosteroid signaling positively regulates ovule number by promoting placentae size and ovule primordia initiation through strengthening auxin response. Transcriptomic analysis demonstrates numerous known regulators of ovule development and hormone signaling, and many new genes are identified that are involved in ovule development. Taken together, our results illustrate that the ovule primordia initiate asynchronously and the hormone signals are involved in the asynchrony.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Membrana Transportadoras/genética , Óvulo Vegetal/genética , Desenvolvimento Vegetal/genética , Transcriptoma/genética , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Frutas/genética , Frutas/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas/genética , Ácidos Indolacéticos/metabolismo , Óvulo Vegetal/crescimento & desenvolvimento , Sementes/genética , Sementes/crescimento & desenvolvimento , Transdução de Sinais/genética
5.
J Exp Bot ; 73(18): 6133-6149, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-35662326

RESUMO

Heading date, panicle architecture, and grain size are key traits that affect the yield of rice (Oryza sativa). Here, we identified a new gene, OsGATA6, whose product regulates heading date. Overexpression of OsGATA6 resulted in delayed heading, increased grain number, and decreased grain size. Knockdown lines generated by artificial microRNA (amiRNA) and CRISPR genome-edited lines of OsGATA6 both showed earlier heading, decreased grain number, and increased grain size. These results suggested that OsGATA6 negatively regulates heading date, positively regulates panicle development, and affects grain size. OsGATA6 was found to be constitutively expressed in rice, and strongly expressed in young leaves and panicles. In situ hybridization analyses showed that OsGATA6 was specifically localized in superficial cells of the panicle primordium. Overexpression lines show decreased expression of RFT1 and Hd3a, which promote heading. OsMFT1, which delays heading date and increases grain number, was down-regulated in amiRNA lines. Further analyses showed that OsGATA6 could bind to the promoter of OsMFT1 and induce its expression, thereby regulating heading date and panicle development. Overexpression of OsGATA6 in Arabidopsis resulted in repressed expression of AtFT and late flowering, suggesting that its function is similar. Taken together, we have identified a new GATA regulator that influences rice heading date and grain number, which potentially increases rice yield.


Assuntos
MicroRNAs , Oryza , Oryza/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Grão Comestível/genética , Grão Comestível/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo
7.
J Integr Plant Biol ; 64(3): 702-716, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34837335

RESUMO

Ovule initiation is a key step that strongly influences ovule number and seed yield. Notably, mutants with enhanced brassinosteroid (BR) and cytokinin (CK) signaling produce more ovules and have a higher seed number per silique (SNS) than wild-type plants. Here, we crossed BR- and CK-related mutants to test whether these phytohormones function together in ovule initiation. We determined that simultaneously enhancing BR and CK contents led to higher ovule and seed numbers than enhancing BR or CK separately, and BR and CK enhanced each other. Further, the BR-response transcription factor BZR1 directly interacted with the CK-response transcription factor ARABIDOPSIS RESPONSE REGULATOR1 (ARR1). Treatments with BR or BR plus CK strengthened this interaction and subsequent ARR1 targeting and induction of downstream genes to promote ovule initiation. Enhanced CK signaling partially rescued the reduced SNS phenotype of BR-deficient/insensitive mutants whereas enhanced BR signaling failed to rescue the low SNS of CK-deficient mutants, suggesting that BR regulates ovule initiation and SNS through CK-mediated and -independent pathways. Our study thus reveals that interaction between BR and CK promotes ovule initiation and increases seed number, providing important clues for increasing the seed yield of dicot crops.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Brassinosteroides/metabolismo , Brassinosteroides/farmacologia , Citocininas/metabolismo , Regulação da Expressão Gênica de Plantas , Óvulo Vegetal/genética , Óvulo Vegetal/metabolismo , Sementes/genética , Sementes/metabolismo
8.
New Phytol ; 225(4): 1606-1617, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31569267

RESUMO

Two types of tonoplast proton pumps, H+ -pyrophosphatase (V-PPase) and the H+ -ATPase (V-ATPase), establish the proton gradient that powers molecular traffic across the tonoplast thereby facilitating turgor regulation and nutrient homeostasis. However, how proton pumps regulate development remains unclear. In this study, we investigated the function of two types of proton pumps in Arabidopsis embryo development and pattern formation. While disruption of either V-PPase or V-ATPase had no obvious effect on plant embryo development, knocking out both resulted in severe defects in embryo pattern formation from the early stage. While the first division in wild-type zygote was asymmetrical, a nearly symmetrical division occurred in the mutant, followed by abnormal pattern formation at all stages of embryo development. The embryonic defects were accompanied by dramatic differences in vacuole morphology and distribution, as well as disturbed localisation of PIN1. The development of mutant cotyledons and root, and the auxin response of mutant seedlings supported the hypothesis that mutants lacking tonoplast proton pumps were defective in auxin transport and distribution. Taking together, we proposed that two tonoplast proton pumps are required for vacuole morphology and PIN1 localisation, thereby controlling vacuole and auxin-related developmental processes in Arabidopsis embryos and seedlings.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/embriologia , Desenvolvimento Embrionário/fisiologia , Pirofosfatase Inorgânica/metabolismo , ATPases Translocadoras de Prótons/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/fisiologia , Gravitropismo/fisiologia , Pirofosfatase Inorgânica/genética , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Mutação , Naftóis/farmacologia , Ftalimidas/farmacologia , Raízes de Plantas/crescimento & desenvolvimento , Transporte Proteico
9.
Microb Pathog ; 117: 49-54, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29438717

RESUMO

Ankylosing spondylitis (AS) is a chronic inflammatory arthritis of unknown origin. Its autoimmune origin has been suggested but never proven. Several reports have implicated K. pneumoniae as a triggering or perpetuating factor in AS; and the HLA-B27 antigen has also been found in association with AS. But there is no satisfactory explanation of why the presence of HLA-B27 predisposes to AS and the precise role played by K. pneumoniae in the disease has not yet been clarified. However, various studies have shown that the results of molecular, immunological, and microbiological studies could establish the link between K. pneumoniae infections and HLA-B27 in the aetiopathogenesis of AS. In this review, we have examined the evidence linking the interaction between K. pneumoniae infections and HLA-B27 in AS, and tried to exploit the possible mechanisms by which K. pneumoniae infections might induce pathologic processes to develop novel diagnostic criteria. Finally, we have also summarized some dietary regimens that could be helpful in the therapeutic management of AS patients.


Assuntos
Antígeno HLA-B27/imunologia , Infecções por Klebsiella/complicações , Infecções por Klebsiella/imunologia , Klebsiella pneumoniae/imunologia , Klebsiella pneumoniae/patogenicidade , Espondilite Anquilosante/etiologia , Espondilite Anquilosante/imunologia , Animais , Anticorpos Antibacterianos/imunologia , Autoanticorpos , Causalidade , Reações Cruzadas , Bases de Dados Factuais , Dieta , Dietoterapia , Humanos , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/metabolismo , Mimetismo Molecular , Espondilite Anquilosante/dietoterapia , Espondilite Anquilosante/microbiologia , Amido/metabolismo
10.
Int J Med Sci ; 15(13): 1433-1442, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30443162

RESUMO

Renal tubule cell apoptosis plays a pivotal role in the progression of chronic renal diseases. The previous study indicates that Sirolimus is effective on unilateral ureteral obstruction (UUO)-induced renal fibrosis. However, the role of Sirolimus in renal tubular apoptosis induced by UUO has not yet been addressed. The aim of this study was to determine the role of Sirolimus in renal tubular apoptosis induced by UUO. Male Sprague-Dawley rats were divided into three groups, sham-operated rats, and after which unilateral ureteral obstruction (UUO) was performed: non-treated and sirolimus-treated (1mg/kg). After 4, 7 and 14 d, animals were sacrificed and blood, kidney tissue samples were collected for analyses. Histologic changes and interstitial collagen were determined microscopically following HE and Masson's trichrome staining. The expression of PCNA was investigated using immunohistochemistry and the expression of Bcl-2, Bax, caspase-9, and caspase-3 were investigated using Western blot in each group. Tubular apoptotic cell deaths were assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay. Sirolimus administration resulted in a significant reduction in tubulointerstitial fibrosis scores. After UUO, there was an increase in tubular and interstitial apoptosis in untreated controls as compared to Sirolimus treatment rats (P<0.05). In addition, the expression of PCNA, Bcl-2, Bax, caspase-9, and caspase-3 in obstructed kidney was characterized by immunohistochemistry and Western blot analyses demonstrating that sirolimus treatment significantly reduced PCNA, Bax, caspase-9 and cleaved caspase-3 expression compared to those observed in controls (P<0.05), whereas, Bcl-2 in the obstructed kidney were decreased in untreated controls compared to Sirolimus treatment rats subjected to the same time course of obstruction (P<0.05). We demonstrated a marked renoprotective effect of sirolimus by inhibition of UUO-induced renal tubular apoptosis in vivo.


Assuntos
Sirolimo/uso terapêutico , Obstrução Ureteral/tratamento farmacológico , Obstrução Ureteral/metabolismo , Animais , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 9/metabolismo , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Rim/efeitos dos fármacos , Rim/metabolismo , Masculino , Antígeno Nuclear de Célula em Proliferação/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos
11.
Neurol Sci ; 39(2): 225-234, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29110148

RESUMO

Vitamin D receptor (VDR) polymorphisms have been inconsistently investigated in multiple sclerosis (MS). However, published studies demonstrated differences concerning design and effect size. A meta-analysis is necessary to determine the magnitude of the association between VDR polymorphisms and MS risk. The aim of the current study was to quantify the magnitude of the association between BsmI, FokI, ApaI, and TaqI VDR polymorphisms and MS risk. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we conducted a systematic search and meta-analysis of the VDR gene polymorphisms and the risk of MS. The pooled odds ratios (OR) and 95% confidence interval (CI) were calculated by using Stata Version 11.0 with dominant and recessive models and allele analyses. A total of 4013 cases and 4218 controls in 24 case-control studies were included in the meta-analyses. The results did not indicate an association between any of the VDR polymorphisms and the risk of MS among overall populations, Asians, and Caucasians. However, our subgroup analysis suggests that the A allele was associated with MS risk in Asian populations (P = 0.005, OR = 1.267, 95% CI 1.074-1.496). Interestingly, the sensitivity analysis excluding studies with controls not in HWE showed insignificant association between the A allele and MS risk (P = 0.211), which was different from those in the non-sensitivity analysis. Our preliminary results indicate the VDR gene ApaI, BsmI, FokI, and TaqI polymorphisms may not be associated with elevated MS risk among overall populations. But ApaI polymorphism may confer different susceptibility to MS among different populations, and more well-designed studies with a large sample size are still needed to validate our results.


Assuntos
Predisposição Genética para Doença , Esclerose Múltipla/genética , Polimorfismo Genético/genética , Receptores de Calcitriol/genética , Povo Asiático/genética , Estudos de Casos e Controles , Humanos
12.
Mod Rheumatol ; 28(4): 681-689, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29043878

RESUMO

OBJECTIVES: The main objective of this study was to summarize the existing evidence and quantitatively evaluate whether serum/plasma levels of homocysteine (Hcy) were associated with sclerosis (SSc) diseases by performing a meta-analysis of previous studies. METHODS: PubMed, Elsevier ScienceDirect and Cochrane Library databases were used to obtain all relative published literatures. Stata version 11.0 (StataCorp, College Station, TX) was used for statistical analysis. The effect size of each study was calculated by the standardized mean difference (SMD) with 95% confidence interval (CI) or quartiles. RESULTS: A total of eight studies including 475 cases and 265 controls were finally included in this meta-analysis. We found significant between-study heterogeneity and conducted analyses using random-effects models. No significant association was found between the serum levels of Hcy and SSc (pooled SMD =1.382 µmol/L, 95%CI = -0.442 to 3.206, p = .137), but there are two outlier studies that deviate significantly from most other studies, which made it difficult to generalize these results. After excluding these two studies, six studies were included in the meta-analysis. The results showed that the serum levels of Hcy in SSc were significantly higher than that in healthy controls (pooled SMD = 1.182µmol/L, 95%CI = 0.230-2.134, p = .015). CONCLUSION: Serum/plasma levels of Hcy in SSc diseases were higher than that in healthy controls.


Assuntos
Homocisteína/sangue , Escleroderma Sistêmico/sangue , Biomarcadores/sangue , Humanos , Escleroderma Sistêmico/patologia
13.
Yi Chuan ; 40(8): 668-675, 2018 Aug 16.
Artigo em Zh | MEDLINE | ID: mdl-30117422

RESUMO

The adverse reaction to irinotecan is related to the single nucleotide polymorphism (SNP) of UGT1A1*6 genotype. The current SNP detection methods have various disadvantages, including time-consuming procedures, high- risk cross-contamination, and cumbersome operation. Hence, it is necessary to establish a new method suitable for clinical application, which is easy and simple to detect SNP with minimal risk for cross-contamination. In this study, a cascade invader assay-based real-time PCR, for UGT1A1*6 genotyping has been established by optimizing reaction conditions with DNA samples of three genotypes. The sensitivity and accuracy of the method were evaluated with DNAs derived from oral swab samples. The results showed that the method could detect the UGT1A1*6 genotypes from the oral swab samples with a detection limit of 6 ng genomic DNA with 100% accuracy. Due to its convenient and non-invasive sampling, single close-tube operation, and minimal risk for cross-contamination, the method has the potential in clinical application for individualized detection of drug-related UGT1A1*6 polymorphism and reaction to irinotecan.


Assuntos
Glucuronosiltransferase/genética , Polimorfismo de Nucleotídeo Único , Reação em Cadeia da Polimerase em Tempo Real/métodos , Saliva/química , Genótipo , Humanos
14.
Cell Immunol ; 318: 1-7, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28651741

RESUMO

It has been established that smoking has a profound impact on susceptibility and severity in some rheumatic diseases (e.g., rheumatoid arthritis), a mild impact in others (e.g., systemic lupus erythematosus) through epidemiological studies. And smoking is known to affect many inflammatory and autoimmune diseases through various mechanisms, including immunomodulation and chemical exposure. Although similar studies investigating the role of cigarette exposure in susceptibility to SSc have been rarely reported and specific mechanisms have never been established, the relationship between smoking and some SSc-related symptoms have been demonstrated during the last decade. However, due to the diversity of study designs, control populations, patient populations and the methodology used to determine smoking history, these results are contradictory in some respects. This paper will review current evidence on the association between smoking and SSc and summarize potential mechanisms.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Escleroderma Sistêmico/imunologia , Fumar/efeitos adversos , Animais , Autoimunidade , Medicina Baseada em Evidências , Humanos , Imunomodulação , Inflamação , Risco , Escleroderma Sistêmico/epidemiologia
15.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 48(2): 173-178, 2017 Mar.
Artigo em Zh | MEDLINE | ID: mdl-28612522

RESUMO

OBJECTIVES: To investigate the effects of trimetazidine (TMZ) on the oxidative stress injury in adipose-derived mesenchymal stem cells (ADSCs). METHODS: ADSCs derived from adipose tissue of SD rats were characterized by flow cytometry and multiline age differentiation. ADSCs apoptosis was induced by H2O2 in vitro , Dirrerent concentration of TMZ (250 µmol/L, 500 µmol/L) was used to protect ADSCs from apoptosis. The morphological features of apoptotic ADSCs were analyzed by Hoechst 33342, mitochondrial potential and structure was analyzed by JC-1 staining and electron microscope, respectively. The apoptotic proteins were detected by Western blot. The effect of TMZ on antioxidant capacity of ADSCs was evaluated by detecting reactive oxygen species (ROS), superoxide dismutase (SOD), glutathione (GSH) and malondialdehyde (MDA). RESULTS: The isolated ADSCs expressed high levels of CD29 and CD90, low levels of CD34 and CD45 and no expression of CD31. ADSCs could be induced to adipocyte and osteoplastic cells. After being treated by H2O2, ADSCs displayed apoptosis characteristics with increased number of apoptotic cells, decreased mitochondrial transmembrane potential and damaged mitochondria. The expressions of apoptotic proteins, including Bax, Bad, and Caspase3, were dramatically increased compared to the controls; however, the anti-apoptotic protein Bcl2 was decreased. At the meantime, the contents of ROS and MDA were elevated, but the concentrations of SOD and GSH were reduced. The treatment of TMZ could partly reverse above negative impacts to ADSCs. CONCLUSION: TMZ could improve the survival rate of ADSCs by enhancing anti-oxidant defense systems to remove excessive ROS and regulating the expression of protective protein.


Assuntos
Tecido Adiposo/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Estresse Oxidativo , Trimetazidina/farmacologia , Animais , Antígenos CD/metabolismo , Células Cultivadas , Glutationa/metabolismo , Peróxido de Hidrogênio , Malondialdeído/metabolismo , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
16.
Acta Pharmacol Sin ; 37(3): 390-7, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26806298

RESUMO

AIM: Adiponectin has been implicated in the development of chronic obstructive pulmonary disease (COPD). The CDH13 gene encodes T-cadherin that is an adiponectin receptor, and genetic variants of CDH13 determine blood adiponectin levels. The aim of this study was to investigate the effects of CDH13 variants on COPD susceptibility in a Chinese population. METHODS: Ten single-nucleotide polymorphisms (SNP) in CDH13 were screened using the SNaPshot method in 279 COPD patients and 367 control subjects. Association of genotypes or haplotypes constructed from these loci with COPD was analyzed in different genetic models. RESULTS: Among the 10 SNPs tested, rs4783244 and rs12922394 exhibited significant differences in allele or genotype frequencies between COPD patients and control subjects, whereas 8 other SNPs did not. The minor allele T was associated with decreased risk of COPD in the recessive model at rs4783244 (OR=0.42, P=0.023) and in the dominant model at rs12922394 (OR=0.70, P=0.022). The genotype TT at either rs4783244 or rs12922394 was associated with a significantly low level of plasma adiponectin when compared to genotypes GG and CC (P<0.05). Haplotypes GC in block 1 (rs4783244-rs12922394) as well as GTAC and ATGT in block 3 (rs4783266-rs11640522-rs11646849-rs11860282) significantly increased the risk of COPD, whereas haplotypes TT in block 1, TG in block 2 (rs11646011- rs11640875) and ATGC in block 3 were protective against COPD. CONCLUSION: CDH13 genetic variants determine Chinese individuals' susceptibility to COPD and thus are efficient genetic biomarkers for early detection of COPD.


Assuntos
Caderinas/genética , Polimorfismo de Nucleotídeo Único , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/genética , Adiponectina/sangue , Idoso , Povo Asiático/genética , China/epidemiologia , Feminino , Predisposição Genética para Doença , Genótipo , Haplótipos , Humanos , Desequilíbrio de Ligação , Pulmão/metabolismo , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/sangue , Doença Pulmonar Obstrutiva Crônica/fisiopatologia
17.
Cell Biol Int ; 38(1): 50-63, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24030871

RESUMO

Deregulation of the mammalian target of rapamycin pathway (mTOR pathway) is associated with human cancer. The relationship between mTOR pathway and histone acetylation is still unclear in gastric cancer (GC). Immunohistochemistry was used to examine the phosphorylation of mTOR and eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1) in GC tissues. MKN45 and SGC7901 cells were treated with the mTOR inhibitor rapamycin (RAPA) alone or in combination with the phosphatidylinositol 3-kinase inhibitor LY294002 and the histone deacetylase (HDAC) inhibitor trichostatin A (TSA). Small interfering RNA (siRNA) technology was also used to knockdown mTOR. Phosphorylated mTOR and phosphorylated 4E-BP1 were expressed in 71.1% and 68.4% of the human GC tissues tested, respectively; significantly higher than the levels in para-cancerous tissues (50% and 57.9%) and normal tissues (44.6% and 29%). RAPA markedly inhibited cell proliferation, induced G1 cell cycle arrest, and reduced phosphorylation of p70 S6 protein kinase (p70S6K) and 4E-BP1 in GC cells, particularly when used in combination with LY294002 or TSA. The mRNA expression of the tumour suppressor gene p21(WAF1) increased significantly in GC cells treated with both RAPA and TSA. Histone acetylation also increased after RAPA and TSA treatment or siRNA knockdown of mTOR. Our findings suggest that the mTOR pathway is activated in GC, and also that inhibition of mTOR enhances the ability of TSA to suppress cell proliferation and lead to cell cycle arrest via increasing histone acetylation and p21(WAF1) transcription in human MKN45 and SGC7901 GC cells.


Assuntos
Inibidores de Histona Desacetilases/farmacologia , Histonas/metabolismo , Ácidos Hidroxâmicos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Acetilação , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adulto , Idoso , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Humanos , Pessoa de Meia-Idade , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Fosfoproteínas/metabolismo , Fosforilação/efeitos dos fármacos , Interferência de RNA , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/genética , Regulação para Cima/efeitos dos fármacos
18.
Cell Rep Med ; 5(6): 101592, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38843841

RESUMO

Environmental lipids are essential for fueling tumor energetics, but whether these exogenous lipids transported into cancer cells facilitate immune escape remains unclear. Here, we find that CD36, a transporter for exogenous lipids, promotes acute myeloid leukemia (AML) immune evasion. We show that, separately from its established role in lipid oxidation, CD36 on AML cells senses oxidized low-density lipoprotein (OxLDL) to prime the TLR4-LYN-MYD88-nuclear factor κB (NF-κB) pathway, and exogenous palmitate transfer via CD36 further potentiates this innate immune pathway by supporting ZDHHC6-mediated MYD88 palmitoylation. Subsequently, NF-κB drives the expression of immunosuppressive genes that inhibit anti-tumor T cell responses. Notably, high-fat-diet or hypomethylating agent decitabine treatment boosts the immunosuppressive potential of AML cells by hijacking CD36-dependent innate immune signaling, leading to a dampened therapeutic effect. This work is of translational interest because lipid restriction by US Food and Drug Administration (FDA)-approved lipid-lowering statin drugs improves the efficacy of decitabine therapy by weakening leukemic CD36-mediated immunosuppression.


Assuntos
Antígenos CD36 , Decitabina , Leucemia Mieloide Aguda , Metabolismo dos Lipídeos , Lipoproteínas LDL , Antígenos CD36/metabolismo , Antígenos CD36/genética , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Decitabina/farmacologia , Decitabina/uso terapêutico , Lipoproteínas LDL/metabolismo , Animais , NF-kappa B/metabolismo , Linhagem Celular Tumoral , Fator 88 de Diferenciação Mieloide/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Camundongos , Transdução de Sinais/efeitos dos fármacos , Evasão Tumoral/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo , Aciltransferases/genética , Imunidade Inata/efeitos dos fármacos , Camundongos Endogâmicos C57BL
20.
Biogerontology ; 14(4): 353-63, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23740528

RESUMO

TOR (target of rapamycin) pathway has been well known for its central role in growth control. Interestingly, recent studies also implicate the TOR pathway in lifespan regulation in various organisms ranging from budding yeast to mammals. TOR gains momentum in a study showing that rapamycin administration later in life significantly extends lifespan in mice. How the TOR kinase controls these two seemingly distinct biological processes is an especially intriguing question yet to be answered. Here, we summarize the literatures concerning TOR's role in growth control, stress response and lifespan regulation, hoping to obtain a better understanding of how cell growth and maintenance are balanced by TOR and how TOR-mediated shift in metabolisms or energy allocations may translate into lifespan extension at the organismal level. We also evaluate the undergoing efforts to target the TOR pathway for health in human, with focus on looking for new drugs that can bypass the unwanted side effects of rapamycin derivatives.


Assuntos
Longevidade , Serina-Treonina Quinases TOR/fisiologia , Adenilato Quinase/metabolismo , Animais , Estresse Oxidativo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/fisiologia
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