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1.
Cell ; 181(6): 1263-1275.e16, 2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32437658

RESUMO

Very low-carbohydrate, high-fat ketogenic diets (KDs) induce a pronounced shift in metabolic fuel utilization that elevates circulating ketone bodies; however, the consequences of these compounds for host-microbiome interactions remain unknown. Here, we show that KDs alter the human and mouse gut microbiota in a manner distinct from high-fat diets (HFDs). Metagenomic and metabolomic analyses of stool samples from an 8-week inpatient study revealed marked shifts in gut microbial community structure and function during the KD. Gradient diet experiments in mice confirmed the unique impact of KDs relative to HFDs with a reproducible depletion of bifidobacteria. In vitro and in vivo experiments showed that ketone bodies selectively inhibited bifidobacterial growth. Finally, mono-colonizations and human microbiome transplantations into germ-free mice revealed that the KD-associated gut microbiota reduces the levels of intestinal pro-inflammatory Th17 cells. Together, these results highlight the importance of trans-kingdom chemical dialogs for mediating the host response to dietary interventions.


Assuntos
Microbioma Gastrointestinal/imunologia , Microbioma Gastrointestinal/fisiologia , Intestinos/imunologia , Intestinos/microbiologia , Células Th17/imunologia , Células Th17/fisiologia , Adolescente , Adulto , Animais , Dieta Hiperlipídica/métodos , Dieta Cetogênica/métodos , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microbiota/imunologia , Microbiota/fisiologia , Pessoa de Meia-Idade , Células Th17/microbiologia , Adulto Jovem
2.
Cell ; 166(3): 755-765, 2016 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-27372738

RESUMO

To provide a detailed analysis of the molecular components and underlying mechanisms associated with ovarian cancer, we performed a comprehensive mass-spectrometry-based proteomic characterization of 174 ovarian tumors previously analyzed by The Cancer Genome Atlas (TCGA), of which 169 were high-grade serous carcinomas (HGSCs). Integrating our proteomic measurements with the genomic data yielded a number of insights into disease, such as how different copy-number alternations influence the proteome, the proteins associated with chromosomal instability, the sets of signaling pathways that diverse genome rearrangements converge on, and the ones most associated with short overall survival. Specific protein acetylations associated with homologous recombination deficiency suggest a potential means for stratifying patients for therapy. In addition to providing a valuable resource, these findings provide a view of how the somatic genome drives the cancer proteome and associations between protein and post-translational modification levels and clinical outcomes in HGSC. VIDEO ABSTRACT.


Assuntos
Proteínas de Neoplasias/genética , Neoplasias Císticas, Mucinosas e Serosas/genética , Neoplasias Ovarianas/genética , Proteoma , Acetilação , Instabilidade Cromossômica , Reparo do DNA , DNA de Neoplasias , Feminino , Dosagem de Genes , Humanos , Espectrometria de Massas , Fosfoproteínas/genética , Processamento de Proteína Pós-Traducional , Análise de Sobrevida
3.
Mol Cell ; 82(21): 4099-4115.e9, 2022 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-36208627

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is characterized by excessive hepatic lipid accumulation, which can progress to nonalcoholic steatohepatitis (NASH). Histone deacetylase Sirtuin 6 (SIRT6) regulates NAFLD by regulating metabolism-related gene expression, but an extrachromosomal role for SIRT6 in NAFLD development remains elusive. We investigated whether SIRT6 functions on NAFLD in the cytoplasm. We found that SIRT6 binds saturated fatty acids, especially palmitic acid. This binding leads to its nuclear export, where it deacetylates long-chain acyl-CoA synthase 5 (ACSL5), thereby facilitating fatty acid oxidation. High-fat diet-induced NAFLD is suppressed by ACSL5 hepatic overexpression but is exacerbated by its depletion. As confirmation, overexpression of a deacetylated ACSL5 mimic attenuated NAFLD in Sirt6 liver-specific knockout mice. Moreover, NASH-hepatic tissues from both patients and diet-fed mice exhibited significantly reduced cytoplasmic SIRT6 levels and increased ACSL5 acetylation. The SIRT6/ACSL5 signaling pathway has a critical role in NAFLD progression and might constitute an avenue for therapeutic intervention.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Sirtuínas , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Acil Coenzima A/metabolismo , Camundongos Endogâmicos C57BL , Fígado/metabolismo , Metabolismo dos Lipídeos , Camundongos Knockout , Ácidos Graxos/metabolismo , Sirtuínas/genética , Sirtuínas/metabolismo , Citoplasma/metabolismo
4.
Nature ; 620(7973): 323-327, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37344595

RESUMO

The black phase of formamidinium lead iodide (FAPbI3) perovskite shows huge promise as an efficient photovoltaic, but it is not favoured energetically at room temperature, meaning that the undesirable yellow phases are always present alongside it during crystallization1-4. This problem has made it difficult to formulate the fast crystallization process of perovskite and develop guidelines governing the formation of black-phase FAPbI3 (refs. 5,6). Here we use in situ monitoring of the perovskite crystallization process to report an oriented nucleation mechanism that can help to avoid the presence of undesirable phases and improve the performance of photovoltaic devices in different film-processing scenarios. The resulting device has a demonstrated power-conversion efficiency of 25.4% (certified 25.0%) and the module, which has an area of 27.83 cm2, has achieved an impressive certified aperture efficiency of 21.4%.

5.
EMBO Rep ; 25(3): 1282-1309, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38316900

RESUMO

UBE3A is a common genetic factor in ASD etiology, and transgenic mice overexpressing UBE3A exhibit typical autistic-like behaviors. Because AMPA receptors (AMPARs) mediate most of the excitatory synaptic transmission in the brain, and synaptic dysregulation is considered one of the primary cellular mechanisms in ASD pathology, we investigate here the involvement of AMPARs in UBE3A-dependent ASD. We show that expression of the AMPAR GluA1 subunit is decreased in UBE3A-overexpressing mice, and that AMPAR-mediated neuronal activity is reduced. GluA1 mRNA is trapped in the nucleus of UBE3A-overexpressing neurons, suppressing GluA1 protein synthesis. Also, SARNP, an mRNA nuclear export protein, is downregulated in UBE3A-overexpressing neurons, causing GluA1 mRNA nuclear retention. Restoring SARNP levels not only rescues GluA1 mRNA localization and protein expression, but also normalizes neuronal activity and autistic behaviors in mice overexpressing UBE3A. These findings indicate that SARNP plays a crucial role in the cellular and behavioral phenotypes of UBE3A-induced ASD by regulating nuclear mRNA trafficking and protein translation of a key AMPAR subunit.


Assuntos
Transtorno Autístico , Animais , Camundongos , Camundongos Transgênicos , Neurônios/metabolismo , Processamento de Proteína Pós-Traducional , Transmissão Sináptica/fisiologia
6.
Proc Natl Acad Sci U S A ; 120(2): e2205199120, 2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-36598941

RESUMO

Assembly of protein complexes is facilitated by assembly chaperones. Alpha and gamma adaptin-binding protein (AAGAB) is a chaperone governing the assembly of the heterotetrameric adaptor complexes 1 and 2 (AP1 and AP2) involved in clathrin-mediated membrane trafficking. Here, we found that before AP1/2 binding, AAGAB exists as a homodimer. AAGAB dimerization is mediated by its C-terminal domain (CTD), which is critical for AAGAB stability and is missing in mutant proteins found in patients with the skin disease punctate palmoplantar keratoderma type 1 (PPKP1). We solved the crystal structure of the dimerization-mediating CTD, revealing an antiparallel dimer of bent helices. Interestingly, AAGAB uses the same CTD to recognize and stabilize the γ subunit in the AP1 complex and the α subunit in the AP2 complex, forming binary complexes containing only one copy of AAGAB. These findings demonstrate a dual role of CTD in stabilizing resting AAGAB and binding to substrates, providing a molecular explanation for disease-causing AAGAB mutations. The oligomerization state transition mechanism may also underlie the functions of other assembly chaperones.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular , Ceratodermia Palmar e Plantar , Humanos , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Proteínas de Transporte/genética , Ceratodermia Palmar e Plantar/genética , Ceratodermia Palmar e Plantar/metabolismo , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Clatrina/metabolismo , Complexo 2 de Proteínas Adaptadoras/genética , Complexo 2 de Proteínas Adaptadoras/metabolismo
7.
Nat Mater ; 23(1): 95-100, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38036625

RESUMO

Inherent symmetry breaking at the interface has been fundamental to a myriad of physical effects and functionalities, such as efficient spin-charge interconversion, exotic magnetic structures and an emergent bulk photovoltaic effect. It has recently been demonstrated that interface asymmetry can induce sizable piezoelectric effects in heterostructures, even those consisting of centrosymmetric semiconductors, which provides flexibility to develop and optimize electromechanical coupling phenomena. Here, by targeted engineering of the interface symmetry, we achieve piezoelectric phenomena behaving as the electrical analogue of the negative Poisson's ratio. This effect, termed the auxetic piezoelectric effect, exhibits the same sign for the longitudinal (d33) and transverse (d31, d32) piezoelectric coefficients, enabling a simultaneous contraction or expansion in all directions under an external electrical stimulus. The signs of the transverse coefficients can be further tuned via in-plane symmetry anisotropy. The effects exist in a wide range of material systems and exhibit substantial coefficients, indicating potential implications for all-semiconductor actuator, sensor and filter applications.

8.
PLoS Pathog ; 19(6): e1011430, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37262100

RESUMO

The mitochondrial electron transport chain (ETC) of apicomplexan parasites differs considerably from the ETC of the animals that these parasites infect, and is the target of numerous anti-parasitic drugs. The cytochrome c oxidase complex (Complex IV) of the apicomplexan Toxoplasma gondii ETC is more than twice the mass and contains subunits not found in human Complex IV, including a 13 kDa protein termed TgApiCox13. TgApiCox13 is homologous to a human iron-sulfur (Fe-S) cluster-containing protein called the mitochondrial inner NEET protein (HsMiNT) which is not a component of Complex IV in humans. Here, we establish that TgApiCox13 is a critical component of Complex IV in T. gondii, required for complex activity and stability. Furthermore, we demonstrate that TgApiCox13, like its human homolog, binds two Fe-S clusters. We show that the Fe-S clusters of TgApiCox13 are critical for ETC function, having an essential role in mediating Complex IV integrity. Our study provides the first functional characterisation of an Fe-S protein in Complex IV.


Assuntos
Parasitos , Toxoplasma , Animais , Humanos , Toxoplasma/metabolismo , Parasitos/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Membranas Mitocondriais/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo
9.
PLoS Pathog ; 19(10): e1011662, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37788227

RESUMO

Coxsackievirus A10 (CVA10) has recently emerged as one of the major causative agents of hand, foot, and mouth disease. CVA10 may also cause a variety of complications. No approved vaccine or drug is currently available for CVA10. The residues of CVA10 critical for viral attachment, infectivity and in vivo pathogenicity have not been identified by experiment. Here, we report the identification of CVA10 residues important for binding to cellular receptor KREMEN1. We identified VP2 N142 as a key receptor-binding residue by screening of CVA10 mutants resistant to neutralization by soluble KREMEN1 protein. The receptor-binding residue N142 is exposed on the canyon rim but highly conserved in all naturally occurring CVA10 strains, which provides a counterexample to the canyon hypothesis. Residue N142 when mutated drastically reduced receptor-binding activity, resulting in decreased viral attachment and infection in cell culture. More importantly, residue N142 when mutated reduced viral replication in limb muscle and spinal cord of infected mice, leading to lower mortality and less severe clinical symptoms. Additionally, residue N142 when mutated could decrease viral binding affinity to anti-CVA10 polyclonal antibodies and a neutralizing monoclonal antibody and render CVA10 resistant to neutralization by the anti-CVA10 antibodies. Overall, our study highlights the essential role of VP2 residue N142 of CVA10 in the interactions with KREMEN1 receptor and neutralizing antibodies and viral virulence in mice, facilitating the understanding of the molecular mechanisms of CVA10 infection and immunity. Our study also provides important information for rational development of antibody-based treatment and vaccines against CVA10 infection.


Assuntos
Anticorpos Neutralizantes , Enterovirus , Animais , Camundongos , Enterovirus/genética , Virulência , Anticorpos Antivirais
10.
Bioessays ; 45(3): e2200198, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36529693

RESUMO

Animal, protist and viral messenger RNAs (mRNAs) are most prominently modified at the beginning by methylation of cap-adjacent nucleotides at the 2'-O-position of the ribose (cOMe) by dedicated cap methyltransferases (CMTrs). If the first nucleotide of an mRNA is an adenosine, PCIF1 can methylate at the N6 -position (m6 A), while internally the Mettl3/14 writer complex can methylate. These modifications are introduced co-transcriptionally to affect many aspects of gene expression including localisation to synapses and local translation. Of particular interest, transcription start sites of many genes are heterogeneous leading to sequence diversity at the beginning of mRNAs, which together with cOMe and m6 Am could constitute an extensive novel layer of gene expression control. Given the role of cOMe and m6 A in local gene expression at synapses and higher brain functions including learning and memory, such code could be implemented at the transcriptional level for lasting memories through local gene expression at synapses.


Assuntos
Metiltransferases , Nucleotídeos , Animais , RNA Mensageiro/metabolismo , Metiltransferases/genética , Metilação , Nucleotídeos/genética , Nucleotídeos/metabolismo , Adenosina/genética , Eucariotos/genética
11.
Nucleic Acids Res ; 51(17): 9166-9182, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37503842

RESUMO

Histone deacetylase 6 (HDAC6) mediates DNA damage signaling by regulating the mismatch repair and nucleotide excision repair pathways. Whether HDAC6 also mediates DNA double-strand break (DSB) repair is unclear. Here, we report that HDAC6 negatively regulates DSB repair in an enzyme activity-independent manner. In unstressed cells, HDAC6 interacts with H2A/H2A.X to prevent its interaction with the E3 ligase RNF168. Upon sensing DSBs, RNF168 rapidly ubiquitinates HDAC6 at lysine 116, leading to HDAC6 proteasomal degradation and a restored interaction between RNF168 and H2A/H2A.X. H2A/H2A.X is ubiquitinated by RNF168, precipitating the recruitment of DSB repair factors (including 53BP1 and BRCA1) to chromatin and subsequent DNA repair. These findings reveal novel regulatory machinery based on an HDAC6-RNF168 axis that regulates the H2A/H2A.X ubiquitination status. Interfering with this axis might be leveraged to disrupt a key mechanism of cancer cell resistance to genotoxic damage and form a potential therapeutic strategy for cancer.


Assuntos
Reparo do DNA , Humanos , Linhagem Celular Tumoral , Dano ao DNA , Desacetilase 6 de Histona/genética , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
12.
Proc Natl Acad Sci U S A ; 119(33): e2200285119, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35939686

RESUMO

Kaposi's sarcoma-associated herpesvirus (KSHV) inhibitor of cyclic GMP-AMP synthase (cGAS) (KicGAS) encoded by ORF52 is a conserved major tegument protein of KSHV and the first reported viral inhibitor of cGAS. In our previous study, we found that KicGAS is highly oligomerized in solution and that oligomerization is required for its cooperative DNA binding and for inhibiting DNA-induced phase separation and activation of cGAS. However, how KicGAS oligomerizes remained unclear. Here, we present the crystal structure of KicGAS at 2.5 Å resolution, which reveals an "L"-shaped molecule with each arm of the L essentially formed by a single α helix (α1 and α2). Antiparallel dimerization of α2 helices from two KicGAS molecules leads to a unique "Z"-shaped dimer. Surprisingly, α1 is also a dimerization domain. It forms a parallel dimeric leucine zipper with the α1 from a neighboring dimer, leading to the formation of an infinite chain of KicGAS dimers. Residues involved in leucine zipper dimer formation are among the most conserved residues across ORF52 homologs of gammaherpesviruses. The self-oligomerization increases the valence and cooperativity of interaction with DNA. The resultant multivalent interaction is critical for the formation of liquid condensates with DNA and consequent sequestration of DNA from being sensed by cGAS, explaining its role in restricting cGAS activation. The structure presented here not only provides a mechanistic understanding of the function of KicGAS but also informs a molecular target for rational design of antivirals against KSHV and related viruses.


Assuntos
Herpesvirus Humano 8 , Nucleotidiltransferases , Proteínas Estruturais Virais , Herpesvirus Humano 8/metabolismo , Humanos , Nucleotidiltransferases/metabolismo , Domínios Proteicos , Multimerização Proteica , Proteínas Estruturais Virais/química
13.
J Biol Chem ; 299(3): 102986, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36754281

RESUMO

Dengue virus (DENV) is one of the most prevalent mosquito-transmitted human viruses that causes significant morbidity and mortality worldwide. To persist in the cell and consequently cause disease, DENV is evolved with mechanisms to suppress the induction of type I interferons by antagonizing cGAS-STING signaling. Using recombinant proteins and in vitro cleavage assays, we have shown that the DENV protease NS2B3 is capable of cleaving cGAS in the N-terminal region without disrupting the C-terminal catalytic center. This generates two major cleavage products: cleavage product N-terminal (CP-N) and cleavage product C-terminal (CP-C). We observed reduction in DNA-binding affinity of CP-C as compared to full-length cGAS. Reduction in DNA-binding affinity is also correlated with the decrease in enzymatic activity of CP-C. CP-N, on the other hand, has almost comparable DNA-binding ability as that of the full-length cGAS. In fact, CP-N competitively inhibits cyclic GMP-AMP production by both full-length cGAS and CP-C. We hypothesize that high DNA-binding affinity of CP-N enables it to sequester the DNA from CP-C and noncleaved full-length cGAS and thus reduces the rate of enzyme activation and cyclic GMP-AMP synthesis. Furthermore, we found that NS2B3 physically interacts with full-length cGAS and CP-C, laying the basis for their shuttling to and eventual degradation in the autophagosome. Overall, our study highlights a multifaceted and effective strategy by which an RNA virus antagonizes cGAS-STING signaling which may be useful for the design of antivirals targeting viral proteases.


Assuntos
Vírus da Dengue , Nucleotidiltransferases , Peptídeo Hidrolases , Humanos , Vírus da Dengue/enzimologia , Imunidade Inata , Nucleotidiltransferases/metabolismo , Peptídeo Hidrolases/metabolismo
14.
Clin Infect Dis ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38920297

RESUMO

BACKGROUND: Remdesivir, an RNA-polymerase prodrug inhibitor approved for treatment of COVID-19, shortens recovery time and improves clinical outcomes. This prespecified analysis compared remdesivir plus standard-of-care (SOC) with SOC alone in adults hospitalized with COVID-19 requiring oxygen support in the early stage of the pandemic. METHODS: Data for 10-day remdesivir treatment plus SOC from the extension phase of an open-label study (NCT04292899) were compared with real-world, retrospective data on SOC alone (EUPAS34303). Both studies included patients aged ≥18 years hospitalized with SARS-CoV-2 up to 30 May 2020, with oxygen saturation ≤94%, on room air or supplemental oxygen (all forms), and with pulmonary infiltrates. Propensity score weighting was used to balance patient demographics and clinical characteristics across treatment groups. The primary endpoint was time to all-cause mortality or end of study (day 28). Time-to-discharge, with a 10-day landmark to account for duration of remdesivir treatment, was a secondary endpoint. RESULTS: 1974 patients treated with remdesivir plus SOC, and 1426 with SOC alone, were included after weighting. Remdesivir significantly reduced mortality versus SOC (hazard ratio [HR]: 0.46, 95% confidence interval: 0.39-0.54). This association was observed at each oxygen support level, with the lowest HR for patients on low-flow oxygen. Remdesivir significantly increased the likelihood of discharge at day 28 versus SOC in the 10-day landmark analysis (HR: 1.64; 95% confidence interval: 1.43-1.87). CONCLUSIONS: Remdesivir plus early-2020 SOC was associated with a 54% lower mortality risk and shorter hospital stays compared with SOC alone in patients hospitalized with COVID-19 requiring oxygen support. CLINICAL TRIALS REGISTRATION: ClinicalTrials.gov NCT04292899 and EUPAS34303.

15.
Breast Cancer Res ; 26(1): 116, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39010116

RESUMO

BACKGROUND: Higher mammographic density (MD), a radiological measure of the proportion of fibroglandular tissue in the breast, and lower terminal duct lobular unit (TDLU) involution, a histological measure of the amount of epithelial tissue in the breast, are independent breast cancer risk factors. Previous studies among predominantly white women have associated reduced TDLU involution with higher MD. METHODS: In this cohort of 611 invasive breast cancer patients (ages 23-91 years [58.4% ≥ 50 years]) from China, where breast cancer incidence rates are lower and the prevalence of dense breasts is higher compared with Western countries, we examined the associations between TDLU involution assessed in tumor-adjacent normal breast tissue and quantitative MD assessed in the contralateral breast obtained from the VolparaDensity software. Associations were estimated using generalized linear models with MD measures as the outcome variables (log-transformed), TDLU measures as explanatory variables (categorized into quartiles or tertiles), and adjusted for age, body mass index, parity, age at menarche and breast cancer subtype. RESULTS: We found that, among all women, percent dense volume (PDV) was positively associated with TDLU count (highest tertile vs. zero: Expbeta = 1.28, 95% confidence interval [CI] 1.08-1.51, ptrend = < .0001), TDLU span (highest vs. lowest tertile: Expbeta = 1.23, 95% CI 1.11-1.37, ptrend = < .0001) and acini count/TDLU (highest vs. lowest tertile: Expbeta = 1.22, 95% CI 1.09-1.37, ptrend = 0.0005), while non-dense volume (NDV) was inversely associated with these measures. Similar trend was observed for absolute dense volume (ADV) after the adjustment of total breast volume, although the associations for ADV were in general weaker than those for PDV. The MD-TDLU associations were generally more pronounced among breast cancer patients ≥ 50 years and those with luminal A tumors compared with patients < 50 years and with luminal B tumors. CONCLUSIONS: Our findings based on quantitative MD and TDLU involution measures among Chinese breast cancer patients are largely consistent with those reported in Western populations and may provide additional insights into the complexity of the relationship, which varies by age, and possibly breast cancer subtype.


Assuntos
Densidade da Mama , Neoplasias da Mama , Mamografia , Humanos , Feminino , Pessoa de Meia-Idade , Neoplasias da Mama/patologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/epidemiologia , Adulto , Idoso , China/epidemiologia , Mamografia/métodos , Idoso de 80 Anos ou mais , Adulto Jovem , Fatores de Risco , Mama/diagnóstico por imagem , Mama/patologia , Glândulas Mamárias Humanas/diagnóstico por imagem , Glândulas Mamárias Humanas/patologia , Glândulas Mamárias Humanas/anormalidades , População do Leste Asiático
16.
Mol Med ; 30(1): 100, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38992588

RESUMO

BACKGROUND: Diabetes mellitus (DM)-induced testicular damage is associated with sexual dysfunction and male infertility in DM patients. However, the pathogenesis of DM-induced testicular damage remains largely undefined. METHODS: A streptozotocin (STZ)-induced diabetic model and high glucose (HG)-treated in vitro diabetic model were established. The histological changes of testes were assessed by H&E staining. Serum testosterone, iron, MDA and GSH levels were detected using commercial kits. Cell viability and lipid peroxidation was monitored by MTT assay and BODIPY 581/591 C11 staining, respectively. qRT-PCR, immunohistochemistry (IHC) or Western blotting were employed to detect the levels of BRD7, Clusterin, EZH2 and AMPK signaling molecules. The associations among BRD7, EZH2 and DNMT3a were detected by co-IP, and the transcriptional regulation of Clusterin was monitored by methylation-specific PCR (MSP) and ChIP assay. RESULTS: Ferroptosis was associated with DM-induced testicular damage in STZ mice and HG-treated GC-1spg cells, and this was accompanied with the upregulation of BRD7. Knockdown of BRD7 suppressed HG-induced ferroptosis, as well as HG-induced Clusterin promoter methylation and HG-inactivated AMPK signaling in GC-1spg cells. Mechanistical studies revealed that BRD7 directly bound to EZH2 and regulated Clusterin promoter methylation via recruiting DNMT3a. Knockdown of Clusterin or inactivation of AMPK signaling reverses BRD7 silencing-suppressed ferroptosis in GC-1spg cells. In vivo findings showed that lack of BRD7 protected against diabetes-induced testicular damage and ferroptosis via increasing Clusterin expression and activating AMPK signaling. CONCLUSION: BRD7 suppressed Clusterin expression via modulating Clusterin promoter hypermethylation in an EZH2 dependent manner, thereby suppressing AMPK signaling to facilitate ferroptosis and induce diabetes-associated testicular damage.


Assuntos
Proteínas Quinases Ativadas por AMP , Clusterina , Metilação de DNA , Diabetes Mellitus Experimental , Ferroptose , Regiões Promotoras Genéticas , Transdução de Sinais , Testículo , Animais , Masculino , Camundongos , Proteínas Quinases Ativadas por AMP/metabolismo , Linhagem Celular , Clusterina/genética , Clusterina/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/complicações , DNA Metiltransferase 3A/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Ferroptose/genética , Camundongos Endogâmicos C57BL , Testículo/metabolismo , Testículo/patologia
17.
J Gene Med ; 26(1): e3632, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38282151

RESUMO

BACKGROUND: Ribosome biogenesis protein BRX1 homolog (BRIX1) is critically required for the synthesis of the 60S ribosome subunit. However, the role and mechanism of BRIX1 in colorectal cancer (CRC) remain unclear. METHODS: Kyoto Encyclopedia of Gene and Genome pathway and Gene Ontology analyses were used for bioinformatics analysis. The rRNA levels were detected in CRC tissues and cells. Nascent RNA synthesis was detected via cellular immunofluorescence. The correlation was analyzed between patient Positron Emission Tomography-Computed Tomography (PET-CT) values and their BRIX1 expression. The extracellular acidification rate (ECAR) and oxygen consumption rate were determined via live metabolic analyses. Polysome fractions were collected for BRIX1 mRNA used in translation. The orthotopic model and Cell Counting Kit-8 (CCK8) assay were used to assess BRIX1 function in CRC. RESULTS: BRIX1 is a core protein involved in ribosome-related pathway changes in CRC. Gene Ontology analysis showed that BRIX1 was primarily enriched in ribosome assembly and ribosome biogenesis pathways. In fresh CRC tissue, rRNA levels (5S, 5.8S, 18S and 28S) were higher in the BRIX1 high-expression group than in the BRIX1 low-expression group. Similarly, BRIX1 knockdown significantly decreased rRNA levels for 5S, 5.8S, 18S and 28S in CRC cells, whereas overexpression of BRIX1 significantly increased these levels. In addition, BRIX1 knockdown inhibited nascent RNA synthesis in CRC cells. In clinical data analysis, BRIX1 expression was related to the glucose uptake in PET-CT. BRIX1 knockdown significantly decreased the ECAR value, glucose uptake and lactic acid production in CRC cells, whereas BRIX1 overexpression significantly increased these. Furthermore, BRIX1 knockdown significantly decreased the protein expression of GLUT1, whereas BRIX1 overexpression significantly increased this; however, expression of BRIX1 mRNA was unaffected in either case. Blocking glycolysis by si-GLUT1 or galactose reversed BRIX1 promotion of glycolysis and cell proliferation in CRC cells.


Assuntos
Neoplasias Colorretais , Transportador de Glucose Tipo 1 , Proteínas Nucleares , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Proliferação de Células/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Glucose/metabolismo , Glicólise , Ribossomos/genética , Ribossomos/metabolismo , RNA Mensageiro/metabolismo , Proteínas Nucleares/genética
18.
Cancer Immunol Immunother ; 73(9): 162, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953977

RESUMO

PURPOSE: To compare the risk of immune-associated pneumonitis between PD-1 and PD-L1 inhibitors, the meta-analysis was designed. METHOD: The difference in risk of immune-associated pneumonitis between PD-1 and PD-L1 inhibitors was assessed by two different meta-analysis methods, the Mirror-pairing and the PRISMA guidelines. RESULTS: A total of eighty-eight reports were used for meta-analysis, while thirty-two studies were used for the Mirror-pairing. Both PD-1 and PD-L1 inhibitors (used alone or combined with chemotherapy) increased the risk of developing immune-related pneumonitis (P < 0.00001; P < 0.00001). Based on indirect analyses results (subgroup analyses), the risk of PD-L1-induced pneumonitis was weaker than that of PD-1 inhibitors when the control group was chemotherapy (OR = 3.33 vs. 5.43) or placebo (OR = 2.53 vs. 3.19), while no obvious significant differences were found (P = 0.17; P = 0.53). For the Mirror-pairing-based meta-analysis, the risk of PD-1-induced pneumonitis was significantly higher than that of PD-L1 inhibitors (OR = 1.46, 95%CI [1.08, 1.98], I2 = 0%, Z = 2.47 (P = 0.01)). However, this difference was not significant, when they were combined with chemotherapy (OR = 1.05, 95%CI [0.68, 1.60], I2 = 38%, Z = 0.21 (P = 0.84)). CONCLUSION: Both PD-1 and PD-L1 inhibitors increased the risk of immune-related pneumonitis, while the risk of PD-1-induced pneumonitis was significantly higher than that of PD-L1 inhibitors.


Assuntos
Antígeno B7-H1 , Inibidores de Checkpoint Imunológico , Pneumonia , Receptor de Morte Celular Programada 1 , Humanos , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Inibidores de Checkpoint Imunológico/efeitos adversos , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Pneumonia/imunologia , Pneumonia/etiologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores
19.
BMC Plant Biol ; 24(1): 340, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671402

RESUMO

Astragalus mongholicus is a medicinal plant that is known to decrease in quality in response to continuous cropping. However, the differences in the root-associated microbiome and root exudates in the rhizosphere soil that may lead to these decreases are barely under studies. We investigated the plant biomass production, root-associated microbiota, and root exudates of A. mongholicus grown in two different fields: virgin soil (Field I) and in a long-term continuous cropping field (Field II). Virgin soil is soil that has never been cultivated for A. mongholicus. Plant physiological measurements showed reduced fresh and dry weight of A. mongholicus under continuous cropping conditions (i.e. Field II). High-throughput sequencing of the fungal and bacterial communities revealed differences in fungal diversity between samples from the two fields, including enrichment of potentially pathogenic fungi in the roots of A. mongholicus grown in Field II. Metabolomic analysis yielded 20 compounds in A. mongholicus root exudates that differed in relative abundance between rhizosphere samples from the two fields. Four of these metabolites (2-aminophenol, quinic acid, tartaric acid, and maleamate) inhibited the growth of A. mongholicus, the soil-borne pathogen Fusarium oxysporum, or both. This comprehensive analysis enhances our understanding of the A. mongholicus microbiome, root exudates, and interactions between the two in response to continuous cropping. These results offer new information for future design of effective, economical approaches to achieving food security.


Assuntos
Microbiota , Raízes de Plantas , Rizosfera , Microbiologia do Solo , Raízes de Plantas/microbiologia , Astrágalo/microbiologia , Exsudatos de Plantas/metabolismo , Fungos/genética , Fungos/fisiologia , Produção Agrícola/métodos , Bactérias/genética , Bactérias/metabolismo
20.
Mol Carcinog ; 63(7): 1378-1391, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38656643

RESUMO

Accumulating evidence suggests that lymphangiogenesis plays a crucial role in lymphatic metastasis, leading to tumor immune tolerance. However, the specific mechanism remains unclear. In this study, miR-431-5p was markedly downregulated in both gastric cancer (GC) tissues and plasma exosomes, and its expression were correlated negatively with LN metastasis and poor prognosis. Mechanistically, miR-431-5p weakens the TGF-ß1/SMAD2/3 signaling pathway by targeting ZEB1, thereby suppressing the secretion of VEGF-A and ANG2, which in turn hinders angiogenesis, lymphangiogenesis, and lymph node (LN) metastasis in GC. Experiments using a popliteal LN metastasis model in BALB/c nude mice demonstrated that miR-431-5p significantly reduced popliteal LN metastasis. Additionally, miR-431-5p enhances the efficacy of anti-PD1 treatment, particularly when combined with galunisertib, anti-PD1 treatment showing a synergistic effect in inhibiting GC progression in C57BL/6 mice. Collectively, these findings suggest that miR-431-5p may modulate the TGF-ß1/SMAD2/3 pathways by targeting ZEB1 to impede GC progression, angiogenesis, and lymphangiogenesis, making it a promising therapeutic target for GC management.


Assuntos
Regulação Neoplásica da Expressão Gênica , Linfangiogênese , Metástase Linfática , Camundongos Endogâmicos BALB C , MicroRNAs , Neovascularização Patológica , Transdução de Sinais , Proteína Smad2 , Proteína Smad3 , Neoplasias Gástricas , Fator de Crescimento Transformador beta1 , Homeobox 1 de Ligação a E-box em Dedo de Zinco , Neoplasias Gástricas/patologia , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Humanos , Animais , MicroRNAs/genética , Linfangiogênese/genética , Camundongos , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Neovascularização Patológica/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta1/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo , Proteína Smad3/metabolismo , Proteína Smad3/genética , Proteína Smad2/metabolismo , Proteína Smad2/genética , Camundongos Nus , Masculino , Feminino , Linhagem Celular Tumoral , Camundongos Endogâmicos C57BL , Prognóstico , Pessoa de Meia-Idade , Angiogênese
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