RESUMO
BACKGROUND: The activated microglia have been reported as pillar factors in neuropathic pain (NP) pathology, but the molecules driving pain-inducible microglial activation require further exploration. In this study, we investigated the effect of dorsal root ganglion (DRG)-derived exosomes (Exo) on microglial activation and the related mechanism. METHODS: A mouse model of NP was generated by spinal nerve ligation (SNL), and DRG-derived Exo were extracted. The effects of DRG-Exo on NP and microglial activation in SNL mice were evaluated using behavioral tests, HE staining, immunofluorescence, and western blot. Next, the differentially enriched microRNAs (miRNAs) in DRG-Exo-treated microglia were analyzed using microarrays. RT-qPCR, RNA pull-down, dual-luciferase reporter assay, and immunofluorescence were conducted to verify the binding relation between miR-16-5p and HECTD1. Finally, the effects of ubiquitination modification of HSP90 by HECTD1 on NP progression and microglial activation were investigated by Co-IP, western blot, immunofluorescence assays, and rescue experiments. RESULTS: DRG-Exo aggravated NP resulting from SNL in mice, promoted the activation of microglia in DRG, and increased neuroinflammation. miR-16-5p knockdown in DRG-Exo alleviated the stimulating effects of DRG-Exo on NP and microglial activation. DRG-Exo regulated the ubiquitination of HSP90 through the interaction between miR-16-5p and HECTD1. Ubiquitination alteration of HSP90 was involved in microglial activation during NP. CONCLUSIONS: miR-16-5p shuttled by DRG-Exo regulated the ubiquitination of HSP90 by interacting with HECTD1, thereby contributing to the microglial activation in NP.
Assuntos
Exossomos , Gânglios Espinais , Proteínas de Choque Térmico HSP90 , MicroRNAs , Microglia , Neuralgia , Animais , Masculino , Camundongos , Modelos Animais de Doenças , Exossomos/metabolismo , Gânglios Espinais/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Camundongos Endogâmicos C57BL , Microglia/metabolismo , MicroRNAs/metabolismo , MicroRNAs/genética , Neuralgia/metabolismo , Neuralgia/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genéticaRESUMO
Species from Candida parapsilosis complex are frequently found in neonatal candidemia. The antifungal agents to treat this infection are limited and the occurrence of low in vitro susceptibility to echinocandins such as micafungin has been observed. In this context, the chaperone Hsp90 could be a target to reduce resistance. Thus, the objective of this research was to identify isolates from the C. parapsilosis complex and verify the action of Hsp90 inhibitors associated with micafungin. The fungal identification was based on genetic sequencing and mass spectrometry. Minimal inhibitory concentrations were determined by broth microdilution method according to Clinical Laboratory and Standards Institute. The evaluation of the interaction between micafungin with Hsp90 inhibitors was realized using the checkerboard methodology. According to the polyphasic taxonomy, C. parapsilosis sensu stricto was the most frequently identified, followed by C. orthopsilosis and C. metapsilosis, and one isolate of Lodderomyces elongisporus was identified by genetic sequencing. The Hsp90 inhibitor geladanamycin associated with micafungin showed a synergic effect in 31.25% of the isolates, a better result was observed with radicicol, which shows synergic effect in 56.25% tested yeasts. The results obtained demonstrate that blocking Hsp90 could be effective to reduce antifungal resistance to echinocandins.
Assuntos
Antifúngicos , Candida parapsilosis , Candidemia , Proteínas de Choque Térmico HSP90 , Micafungina , Humanos , Recém-Nascido , Antifúngicos/farmacologia , Benzoquinonas/farmacologia , Candida parapsilosis/efeitos dos fármacos , Candida parapsilosis/isolamento & purificação , Candida parapsilosis/genética , Candidemia/microbiologia , Farmacorresistência Fúngica , Sinergismo Farmacológico , Equinocandinas/farmacologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/metabolismo , Proteínas de Choque Térmico HSP90/genética , Lactamas Macrocíclicas/farmacologia , Lipopeptídeos/farmacologia , Micafungina/farmacologia , Testes de Sensibilidade MicrobianaRESUMO
In this work, we describe a novel ruthenium-xanthoxylin complex, [Ru(phen)2(xant)](PF6) (RXC), that can eliminate colorectal cancer (CRC) stem cells by targeting the chaperone Hsp90. RXC exhibits potent cytotoxicity in cancer cell lines and primary cancer cells, causing apoptosis in HCT116 CRC cells, as observed by cell morphology, YO-PRO-1/PI staining, internucleosomal DNA fragmentation, mitochondrial depolarization, and PARP cleavage (Asp214). Additionally, RXC can downregulate the HSP90AA1 and HSP90B1 genes and the expression of HSP90 protein, as well as the expression levels of its downstream/client elements Akt1, Akt (pS473), mTOR (pS2448), 4EBP1 (pT36/pT45), GSK-3ß (pS9), and NF-κB p65 (pS529), implying that these molecular chaperones can be molecular targets for RXC. Moreover, this compound inhibited clonogenic survival, the percentage of the CRC stem cell subpopulation, and colonosphere formation, indicating that RXC can eliminate CRC stem cells. RXC reduced cell migration and invasion, decreased vimentin and increased E-cadherin expression, and induced an autophagic process that appeared to be cytoprotective, as autophagy inhibitors enhanced RXC-induced cell death. In vivo studies showed that RXC inhibits tumor progression and experimental metastasis in mice with CRC HCT116 cell xenografts. Taken together, these results highlight the potential of the ruthenium complex RXC in CRC therapy with the ability to eliminate CRC stem cells by targeting the chaperone Hsp90.
Assuntos
Neoplasias Colorretais , Rutênio , Humanos , Animais , Camundongos , Transdução de Sinais , Glicogênio Sintase Quinase 3 beta/metabolismo , Células HCT116 , Proteínas de Choque Térmico HSP90/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Proliferação de Células , Linhagem Celular TumoralRESUMO
IMPORTANCE: In the unicellular parasites Leishmania spp., the etiological agents of leishmaniasis, a complex infectious disease that affects 98 countries in 5 continents, chemical inhibition of HSP90 protein leads to differentiation from promastigote to amastigote stage. Recent studies indicate potential role for protein phosphorylation in the life cycle control of Leishmania. Also, recent studies suggest a fundamentally important role of RNA-binding proteins (RBPs) in regulating the downstream effects of the HSP90 inhibition in Leishmania. Phosphorylation-dephosphorylation dynamics of RBPs in higher eukaryotes serves as an important on/off switch to regulate RNA processing and decay in response to extracellular signals and cell cycle check points. In the current study, using a combination of highly sensitive TMT labeling-based quantitative proteomic MS and robust phosphoproteome enrichment, we show for the first time that HSP90 inhibition distinctively modulates global protein phosphorylation landscapes in the different life cycle stages of Leishmania, shedding light into a crucial role of the posttranslational modification in the differentiation of the parasite under HSP90 inhibition stress. We measured changes in phosphorylation of many RBPs and signaling proteins including protein kinases upon HSP90 inhibition in the therapeutically relevant amastigote stage. This work provides insights into the importance of HSP90-mediated protein cross-talks and regulation of phosphorylation in Leishmania, thus significantly expanding our knowledge of the posttranslational modification in Leishmania biology.
Assuntos
Leishmania mexicana , Leishmania , Leishmania mexicana/metabolismo , Proteômica , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Leishmania/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Proteoma/metabolismoRESUMO
BACKGROUND: The death of oral keratinocytes is a crucial step in the emergence of recurrent aphthous stomatitis (RAS, also known as aphthae or aphthous ulcers). Since there are no experimental models available to research aphthous ulcers, little is understood about this process. We hypothesize that saliva can be a data bank of information that offers insights on epithelial damage. METHODS: In this case-crossover study, we assessed the salivary proteome of patients with RAS (n = 36) in the presence and absence of ulcers using discovery proteomics and bioinformatics. Additionally, we contrasted these patterns with those of healthy individuals (n = 31) who had no prior aphthous ulceration. RESULTS: Salivary proteome showed that during the ulcerative phase, controlled cell death was downregulated. Due to its ability to distinguish between individuals with and without ulcers, the ATF6B protein raises the possibility that endoplasmic reticulum (ER) stress is responsible for the damage that leads to the death of oral keratinocytes. The high abundance of TRAP1 and ERN1 matches with this biological discovery. The type of death is immunogenic, according to the functional data found in a cell death database. CONCLUSION: We identified a cellular process that can lead to the death of oral keratinocytes in the etiopathogenesis process of RAS. Future studies should be conducted to identify what is responsible for the increase in ER stress signaling that would lead to an anti-cell death response.
Assuntos
Estomatite Aftosa , Humanos , Estomatite Aftosa/metabolismo , Estudos Cross-Over , Úlcera/complicações , Proteoma , Proteínas e Peptídeos Salivares , Recidiva , Proteínas de Choque Térmico HSP90RESUMO
Bacillus thuringiensis (Bt) produces different insecticidal proteins effective for pest control. Among them, Cry insecticidal proteins have been used in transgenic plants for the control of insect pests. However, evolution of resistance by insects endangers this technology. Previous work showed that the lepidopteran insect Plutella xylostella PxHsp90 chaperone enhanced the toxicity of Bt Cry1A protoxins by protecting them from degradation by the larval gut proteases and by enhancing binding of the protoxin to its receptors present in larval midgut cells. In this work, we show that PxHsp70 chaperone also protects Cry1Ab protoxin from gut proteases degradation, enhancing Cry1Ab toxicity. We also show that both PxHsp70 and PxHsp90 chaperones act cooperatively, increasing toxicity and the binding of Cry1Ab439D mutant, affected in binding to midgut receptors, to cadherin receptor. Also, insect chaperones recovered toxicity of Cry1Ac protein to a Cry1Ac-highly resistant P. xylostella population, NO-QAGE, that has a disruptive mutation in an ABCC2 transporter linked to Cry1Ac resistance. These data show that Bt hijacked an important cellular function for enhancing its infection capability, making use of insect cellular chaperones for enhancing Cry toxicity and for lowering the evolution of insect resistance to these toxins.
Assuntos
Bacillus thuringiensis , Inseticidas , Animais , Bacillus thuringiensis/genética , Insetos , Larva/genética , Chaperonas Moleculares , Proteínas de Choque Térmico HSP90/genética , Peptídeo Hidrolases , Proteínas de Choque Térmico HSP70/genética , Endotoxinas/toxicidade , Proteínas Hemolisinas/toxicidadeRESUMO
BACKGROUND: Bladder cancer (BLCA) is defined as a type of urinary cancer with high incidence and lack of specific biomarkers and drug targets. Immunogenic cell death (ICD) has been classified as a regulated type of cell death. Growing evidence suggested that ICD can reshape the tumor immune microenvironment, which may contribute to the development of immunotherapy strategies. The aim of this study was to reveal the specific mechanism of ICD in bladder cancer and to further predict the prognostic immunotherapy outcomes. METHODS: By consensus clustering analysis, bladder cancer patients in TCGA database were divided into different ICD subtypes. Additionally, we developed an ICD-scoring system and constructed the ICD score-based risk signature and nomogram to better characterize patients. Furthermore, we carried out a series of experiments to verify the relevant findings. RESULTS: Based on the transcriptome expression levels of ICD-related genes, a total of 403 BLCA patients in the TCGA database were divided into two subgroups with different ICD molecular patterns by consensus cluster analysis. These subgroups showed different clinicopathological features, survival outcomes, tumor microenvironment (TME) characteristics, immune-related scores, and treatment response. Moreover, the established prediction model and ICD score can effectively distinguish high risk/score patients from low risk/score patients, which has excellent predictive value. Finally, we found that the key gene HSP90AA1 was highly expressed in the high-ICD score group and in bladder cancer tissues, and was confirmed to be associated with the proliferation of bladder cancer cells. CONCLUSION: To sum up, we established a new classification system for BLCA based on ICD-related genes. This stratification has significant predictive power for clinical outcomes and can effectively evaluate the prognosis and immunotherapy of BLCA patients. Finally, it was proved that HSP90AA1 was highly expressed in BLCA and would be a promising therapeutic target for BLCA.
Assuntos
Morte Celular Imunogênica , Neoplasias da Bexiga Urinária , Humanos , Neoplasias da Bexiga Urinária/genética , Bexiga Urinária , Imunoterapia , Morte Celular , Microambiente Tumoral , Prognóstico , Proteínas de Choque Térmico HSP90/genéticaRESUMO
Systematic studies have revealed interactions between components of the Hsp90 chaperone system and Fe/S protein biogenesis or iron regulation. In addition, two chloroplast-localized DnaJ-like proteins, DJA5 and DJA6, function as specific iron donors in plastidial Fe/S protein biogenesis. Here, we used Saccharomyces cerevisiae to study the impact of both the Hsp90 chaperone and the yeast DJA5-DJA6 homologs, the essential cytosolic Ydj1, and the mitochondrial Mdj1, on cellular iron-related processes. Despite severe phenotypes induced upon depletion of these crucial proteins, there was no critical in vivo impact on Fe/S protein biogenesis or iron regulation. Importantly, unlike the plant DJA5-DJA6 iron chaperones, Ydj1 and Mdj1 did not bind iron in vivo, suggesting that these proteins use zinc for function under normal physiological conditions.
Assuntos
Proteínas Ferro-Enxofre , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas Ferro-Enxofre/genética , Proteínas Ferro-Enxofre/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Ferro/metabolismo , Proteínas Mitocondriais/metabolismo , Chaperonas Moleculares/metabolismo , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismoRESUMO
This study aimed to verify the effect of different feeding and stocking conditions during 14 days on the gene expression of several hormones and enzymes related to the stress cascade and metabolic parameters in silver catfish Rhamdia quelen under the following experimental conditions: 1) fed at low stocking density (2.5 kg m-3, LSD-F); 2) fed at high stocking density (32 kg m-3, HSD-F); 3) food-deprived at LSD (LSD-FD); and 4) food-deprived at HSD (HSD-FD). Fish from LSD-F and HSD-F groups were fed daily (1 % of their body mass), while fish from food-deprived groups (LSD-FD and HSD-FD) were not fed during the experimental time. Plasma metabolic parameters (glucose, lactate, triglycerides, and proteins) and hepatosomatic index (HSI) were evaluated. In addition, mRNA expression of genes related to the stress axis (crh, pomca, pomcb, nr3c2, star, hsd11b2 and hsd20b), heat shock protein family (hsp90 and hspa12a), sodium-dependent noradrenaline transporter (slc6a2), and growth axis (gh and igf1) were also assessed. Specific growth rate and HSI decreased in food-deprived fish regardless of stocking density. The HSD-FD group showed weight loss compared to the HSD-F, LSD-F, and LSD-FD groups. Plasma glucose and triglycerides were reduced in food-deprived groups, while lactate and protein levels did not change. The expression of key players of the stress response (crh, pomca, pomcb, hsd11b2, nr3c2, and hsp90b) and growth (gh and igf1) pathways were differently regulated depending on the experimental condition, whereas no statistical difference between treatments was found for hsd20b, scl6a2, hspa12a, and star mRNAs expression. This study suggests that LSD acts as a stressor affecting negatively the physiological status of fed fish, as demonstrated by the reduction in growth rates, altered metabolic orchestration, and a higher crh mRNA expression. In addition, food deprivation also increased mRNA expression of other assessed genes (nr3c2, hsp90b, pomca, and pomcb) in fish from the HSD group, indicating higher responsiveness to stress in this stocking density when combined with food deprivation.
Assuntos
Peixes-Gato , Animais , Proteínas de Choque Térmico , Proteínas de Choque Térmico HSP90 , Lactatos , RNA MensageiroRESUMO
Differences in the features of aggressiveness of non-melanoma skin cancer (NMSC) subtypes, between basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are relevant characteristics. Comparing the characteristics between NMSC subtypes might help identify molecules associated with cancer metastasis and invasion. Considering these facts, the current study aimed to identify a molecular target for inhibiting skin cancer metastasis and invasion. Proteomic analysis suggested that heat shock protein 90 kDa, alpha, class B member 1 (HSP90AB1), pentaxin (PTX3), caspase-14 (CASP14), S100, actin-1, and profilin were the primary targets related to metastasis and invasion. However, after a differential expression comparison between BCC and SCC, HSP90AB1 was identified as the best target to repress metastasis and invasion. Based on molecular docking results, gallic acid (GA) was selected to inhibit HSP90AB1. A specific Hsp90ab1 siRNA targeting was designed and compared to GA. Interestingly, GA was more efficient in silencing HSP90AB1 than siRNAhsp90ab1. Hence, our data suggest that HSP90AB1 is a crucial biomarker for identifying invasion and metastasis and that its inhibition may be a viable strategy for treating skin cancer.