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Plants frequently encounter wounding and have evolved an extraordinary regenerative capacity to heal the wounds. However, the wound signal that triggers regenerative responses has not been identified. Here, through characterization of a tomato mutant defective in both wound-induced defense and regeneration, we demonstrate that in tomato, a plant elicitor peptide (Pep), REGENERATION FACTOR1 (REF1), acts as a systemin-independent local wound signal that primarily regulates local defense responses and regenerative responses in response to wounding. We further identified PEPR1/2 ORTHOLOG RECEPTOR-LIKE KINASE1 (PORK1) as the receptor perceiving REF1 signal for plant regeneration. REF1-PORK1-mediated signaling promotes regeneration via activating WOUND-INDUCED DEDIFFERENTIATION 1 (WIND1), a master regulator of wound-induced cellular reprogramming in plants. Thus, REF1-PORK1 signaling represents a conserved phytocytokine pathway to initiate, amplify, and stabilize a signaling cascade that orchestrates wound-triggered organ regeneration. Application of REF1 provides a simple method to boost the regeneration and transformation efficiency of recalcitrant crops.
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Proteínas de Plantas , Regeneração , Transdução de Sinais , Solanum lycopersicum , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Solanum lycopersicum/metabolismo , Regulação da Expressão Gênica de Plantas , Peptídeos/metabolismoRESUMO
Nesprin proteins, which are components of the linker of nucleoskeleton and cytoskeleton (LINC) complex, are located within the nuclear envelope and play prominent roles in nuclear architecture. For example, LINC complex proteins interact with both chromatin and the cytoskeleton. Here, we report that the Drosophila Nesprin MSP300 has an additional function in autophagy within larval body wall muscles. RNAi-mediated MSP300 knockdown in larval body wall muscles resulted in defects in the contractile apparatus, muscle degeneration and defective autophagy. In particular, MSP300 knockdown caused accumulation of cytoplasmic aggregates that contained poly-ubiquitylated cargo, as well as the autophagy receptor ref(2)P (the fly homolog of p62 or SQSTM) and Atg8a. Furthermore, MSP300 knockdown larvae expressing an mCherry-GFP-tagged Atg8a transgene exhibited aberrant persistence of the GFP signal within these aggregates, indicating failure of autophagosome maturation. These autophagy deficits were similar to those exhibited by loss of the endoplasmic reticulum (ER) fusion protein Atlastin (Atl), raising the possibility that Atl and MSP300 might function in the same pathway. In support of this possibility, we found that a GFP-tagged MSP300 protein trap exhibited extensive localization to the ER. Alteration of ER-directed MSP300 might abrogate important cytoskeletal contacts necessary for autophagosome completion.
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Autofagia , Proteínas de Drosophila , Proteostase , Animais , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster/metabolismo , Drosophila melanogaster/genética , Retículo Endoplasmático/metabolismo , Músculos/metabolismo , Larva/metabolismo , Larva/genética , Proteínas dos Microfilamentos , Proteínas MuscularesRESUMO
AP endonuclease-1/Redox factor-1 (APE1/Ref-1 or Ref-1) is a multifunctional protein that is overexpressed in most aggressive cancers and impacts various cancer cell signaling pathways. Ref-1's redox activity plays a significant role in activating transcription factors (TFs) such as NFκB, HIF1α, STAT3 and AP-1, which are crucial contributors to the development of tumors and metastatic growth. Therefore, development of potent, selective inhibitors to target Ref-1 redox function is an appealing approach for therapeutic intervention. A first-generation compound, APX3330 successfully completed phase I clinical trial in adults with progressing solid tumors with favorable response rate, pharmacokinetics (PK), and minimal toxicity. These positive results prompted us to develop more potent analogs of APX3330 to effectively target Ref-1 in solid tumors. In this study, we present structure-activity relationship (SAR) identification and validation of lead compounds that exhibit a greater potency and a similar or better safety profile to APX3330. In order to triage and characterize the most potent and on-target second-generation Ref-1 redox inhibitors, we assayed for PK, mouse and human S9 fraction metabolic stability, in silico ADMET properties, ligand-based WaterLOGSY NMR measurements, pharmacodynamic markers, cell viability in multiple cancer cell types, and two distinct 3-dimensional (3D) cell killing assays (Tumor-Microenvironment on a Chip and 3D spheroid). To characterize the effects of Ref-1 inhibition in vivo, global proteomics was used following treatment with the top four analogs. This study identified and characterized more potent inhibitors of Ref-1 redox function (that outperformed APX3330 by 5-10-fold) with PK studies demonstrating efficacious doses for translation to clinic.
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DNA Liase (Sítios Apurínicos ou Apirimidínicos) , Neoplasias , Adulto , Humanos , Animais , Camundongos , Inibidores da Angiogênese , Apoptose , Bioensaio , Neoplasias/tratamento farmacológico , Microambiente TumoralRESUMO
PURPOSE: Predicting the quantitative fraction of glucuronidation (fgluc) by individual UDP-glucuronosyltransferase enzymes (UGTs) is challenging due to the lack of selective inhibitors and inconsistent activity of recombinant UGT systems (rUGTs). Our study compares the relative expression versus activity factors (REF versus RAF) to predict fgluc based on rUGT data to human liver and intestinal microsomes (HLM and HIM). METHODS: REF scalars were derived from a previous in-house proteomics study for eleven UGT enzymes (UGT1A1, UGT1A3, UGT1A4, UGT1A6, UGT1A9, UGT1A10, UGT2B4, UGT2B7, UGT2B10, UGT2B15, and UGT2B17), whereas RAF was calculated by measuring activities in rUGTs to microsomes of selective UGT probe substrates. Protein-normalized activity factor (pnAF) values were generated after correcting activity of individual UGTs to their corresponding protein abundance. The utility of REF and RAF in predicting fgluc was assessed for three UGT substrates-diclofenac, vorinostat, and raltegravir. RESULTS: The REF values ranged from 0.02 to 1.75, RAF based on activity obtained in rUGTs to HLM/HIM were from 0.1 to 274. pnAF values were ~ 5 to 80-fold, except for UGT2B4 and UGT2B15, where pnAF was ~ 180 and > 1000, respectively. The results revealed confounding effect of differential specific activities (per pmol) of rUGTs in fgluc prediction. CONCLUSION: The data suggest that the activity of UGT enzymes was significantly lower when compared to their activity in microsomes at the same absolute protein amount (pmol). Collectively, results of this study demonstrate poor and variable specific activity of different rUGTs (per pmol protein), as determined by pnAF values, which should be considered in fgluc scaling.
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Glucuronídeos , Glucuronosiltransferase , Microssomos Hepáticos , Proteínas Recombinantes , Glucuronosiltransferase/metabolismo , Glucuronosiltransferase/genética , Humanos , Proteínas Recombinantes/metabolismo , Glucuronídeos/metabolismo , Microssomos Hepáticos/metabolismo , Microssomos/metabolismo , Diclofenaco/metabolismo , Taxa de Depuração Metabólica , Mucosa Intestinal/metabolismoRESUMO
Quality of life may be understood as a multidimensional evaluation of life circumstances in relation to values, expectations, and perceived well-being. Quality of life is thus dependent on the subjective perception of the current life situation, not only objective circumstances. According to metacognitive theory, metacognition guides the appraisal of inner experiences (i.e., thoughts and feelings) and influences how one relates to external stressors. Hence, dysfunctional metacognitive beliefs and the cognitive attentional syndrome (CAS), which includes perseverative thinking, threat monitoring and ineffective coping strategies, may negatively influence subjective quality of life. Therefore, we aimed to investigate if metacognitive beliefs and CAS strategies were associated with quality of life. A sample of 503 participants (77.1% women, mean age 41.0, SD = 11.5) completed the metacognitions questionnaire 30 (MCQ-30), the CAS-1 and the quality of life scale (QOLS). We used structural equation modelling (SEM) to estimate associations between the variables founded in metacognitive theory. The results of the SEM showed a significant direct relationship between metacognitive beliefs and quality of life. CAS strategies mediated the effect of metacognitive beliefs on quality of life. Higher level of metacognitive beliefs was associated with greater use of CAS strategies, which in turn was associated with lower quality of life. Further, more CAS strategies were associated with lower quality of life. The results support the generic metacognitive model and suggest that stronger endorsement of dysfunctional metacognitive beliefs and corresponding CAS strategies are associated with lower quality of life. This observation held even when controlling for relevant covariates and suggests that modifying metacognitive beliefs may impact on subjective quality of life.
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Metacognição , Qualidade de Vida , Humanos , Feminino , Qualidade de Vida/psicologia , Metacognição/fisiologia , Masculino , Adulto , Pessoa de Meia-Idade , Adaptação Psicológica/fisiologia , Atenção/fisiologia , Adulto JovemRESUMO
APE1/Ref-1 (apurinic/apyrimidinic endonuclease 1, APE1 or APEX1; redox factor-1, Ref-1) is a dual-functional enzyme with crucial roles in DNA repair, reduction/oxidation (redox) signaling, and RNA processing and metabolism. The redox function of Ref-1 regulates several transcription factors, such as NF-κB, STAT3, HIF-1α, and others, which have been implicated in multiple human diseases, including ocular angiogenesis, inflammation, and multiple cancers. To better understand how APE1 influences these disease processes, we investigated the effects of APEX1 knockdown (KD) on gene expression in human retinal endothelial cells. This abolishes both DNA repair and redox signaling functions, as well as RNA interactions. Using RNA-seq analysis, we identified the crucial signaling pathways affected following APEX1 KD, with subsequent validation by qRT-PCR. Gene expression data revealed that multiple genes involved in DNA base excision repair, other DNA repair pathways, purine or pyrimidine metabolism signaling, and histidine/one carbon metabolism pathways were downregulated by APEX1 KD. This is in contrast with the alteration of pathways by APEX1 KD in human cancer lines, such as pancreatic ductal adenocarcinoma, lung, HeLa, and malignant peripheral nerve sheath tumors. These results highlight the unique role of APE1/Ref-1 and the clinical therapeutic potential of targeting APE1 and pathways regulated by APE1 in the eye. These findings provide novel avenues for ocular neovascularization treatment.
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Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Células Endoteliais/metabolismo , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Neoplasias Pancreáticas/patologia , Reparo do DNA , Fatores de Transcrição/metabolismo , Carcinoma Ductal Pancreático/genética , OxirreduçãoRESUMO
Apurinic/apyrimidinic endonuclease 1/redox factor-1 (APE1/Ref-1) is a multifunctional protein involved in DNA repair and redox regulation. The redox activity of APE1/Ref-1 is involved in inflammatory responses and regulation of DNA binding of transcription factors related to cell survival pathways. However, the effect of APE1/Ref-1 on adipogenic transcription factor regulation remains unknown. In this study, we investigated the effect of APE1/Ref-1 on the regulation of adipocyte differentiation in 3T3-L1 cells. During adipocyte differentiation, APE1/Ref-1 expression significantly decreased with the increased expression of adipogenic transcription factors such as CCAAT/enhancer binding protein (C/EBP)-α and peroxisome proliferator-activated receptor (PPAR)-γ, and the adipocyte differentiation marker adipocyte protein 2 (aP2) in a time-dependent manner. However, APE1/Ref-1 overexpression inhibited C/EBP-α, PPAR-γ, and aP2 expression, which was upregulated during adipocyte differentiation. In contrast, silencing APE1/Ref-1 or redox inhibition of APE1/Ref-1 using E3330 increased the mRNA and protein levels of C/EBP-α, PPAR-γ, and aP2 during adipocyte differentiation. These results suggest that APE1/Ref-1 inhibits adipocyte differentiation by regulating adipogenic transcription factors, suggesting that APE1/Ref-1 is a potential therapeutic target for regulating adipocyte differentiation.
Assuntos
Receptores Ativados por Proliferador de Peroxissomo , Fatores de Transcrição , Animais , Camundongos , Células 3T3-L1 , Adipócitos/metabolismo , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Diferenciação Celular , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , PPAR gama/metabolismo , Fatores de Transcrição/metabolismoRESUMO
The metacognitive model of generalized anxiety disorder (GAD) places worrying, meta-worry ("worry about worry") and corresponding underlying metacognitive beliefs (i.e., beliefs about worry) as central in the maintenance of symptoms. Previous research has demonstrated significant relationships between these factors and symptoms, but no study has tested the statistical fit of this influential model including its hypothesized components and the suggested paths between them. The aim of the current study was therefore to evaluate the fit of the metacognitive model of GAD. A total of 312 participants constituting an analogue GAD sample were included in a cross-sectional study and completed self-report measures of anxiety and depression symptoms and scales relevant to the metacognitive model. Metacognitions, worry, and meta-worry in their hypothesized order provided a good model fit and explained significant and substantial variance in symptoms. These results provide further support for the metacognitive model of GAD and demonstrates separate and unique contributions from worry and meta-worry to generalized anxiety symptoms of which meta-worry was the most influential.
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Transtornos de Ansiedade , Metacognição , Humanos , Estudos Transversais , Inquéritos e Questionários , Transtornos de Ansiedade/psicologia , Ansiedade/psicologiaRESUMO
Patients with Social Anxiety Disorder (SAD) typically report interpersonal problems, and these are important targets in treatment beyond social anxiety symptoms as they impair quality of life, maintain emotion symptoms and effect on social functioning. What factors contribute to interpersonal problems? In the current study we set out to explore the role of metacognitive beliefs as correlates of interpersonal problems in patients treated for SAD when controlling for the effect of social phobic cognitions and symptoms. The sample consisted of 52 patients with a primary diagnosis of SAD participating in a randomized controlled trial comparing cognitive therapy, paroxetine, pill placebo, or the combination of cognitive therapy and paroxetine in treating SAD. Two hierarchical multiple linear regression analyses were conducted to explore change in metacognitions as predictors of change in interpersonal problems when controlling for change in social phobic cognitions and social anxiety. Change in metacognitions accounted for unique variance in interpersonal problems improvement beyond change in cognitions. Furthermore, change in cognitions overlapped with change in social anxiety symptoms, and when controlling the overlap between these three predictors, only change in metacognitions was uniquely associated with improvement in interpersonal problems. This finding indicates that metacognitions are linked to interpersonal problems in patients with SAD with the implication that treatment should aim to modify metacognitive beliefs to alleviate interpersonal dysfunction.
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Metacognição , Fobia Social , Humanos , Fobia Social/terapia , Paroxetina , Qualidade de Vida , Cognição , Ansiedade/psicologiaRESUMO
In this paper, we investigated water exchange reactions and substitution of aqua RuII complexes of general formula [Ru(terpy)(N^N)(H2 O)]2+ (where N^N = ethylenediamine (en), 1,2-(aminomethyl)pyridine (ampy) and 2,2'-bipyridine (bipy)) by ammonia and thioformaldehyde. These reactions were studied in detail by applying conceptual density functional theory. This approach enabled us to gain further insight into the underlying reaction mechanism at the microscopic level (involving only direct participants of the reaction, without the influence of the solvent) and to put the concept of reaction mechanism on a quantitative basis. The course of the chemical reaction along the reaction coordinate ξ, is rationalized in terms of reaction energy, force, dipole moment, and reaction electronic flux (REF). The results yield and characterize the significant influence of an intermolecular hydrogen bond formed between the entering and the spectator ligand to the overall energy barrier of the reactions.
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Enteric neuropathy underlies long-term gastrointestinal (GI) dysfunction associated with several pathological conditions. Our previous studies have demonstrated that structural and functional changes in the enteric nervous system (ENS) result in persistent alterations of intestinal functions long after the acute insult. These changes lead to aberrant immune response and chronic dysregulation of the epithelial barrier. Damage to the ENS is prognostic of disease progression and plays an important role in the recurrence of clinical manifestations. This suggests that the ENS is a viable therapeutic target to alleviate chronic intestinal dysfunction. Our recent studies in preclinical animal models have progressed into the development of novel therapeutic strategies for the treatment of enteric neuropathy in various chronic GI disorders. We have tested the anti-inflammatory and neuroprotective efficacy of novel compounds targeting specific molecular pathways. Ex vivo studies in human tissues freshly collected after resection surgeries provide an understanding of the molecular mechanisms involved in enteric neuropathy. In vivo treatments in animal models provide data on the efficacy and the mechanisms of actions of the novel compounds and their combinations with clinically used therapies. These novel findings provide avenues for the development of safe, cost-effective, and highly efficacious treatments of GI disorders.
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Sistema Nervoso Entérico , Gastroenteropatias , Pseudo-Obstrução Intestinal , Animais , Humanos , Sistema Nervoso Entérico/patologia , Gastroenteropatias/tratamento farmacológico , Pseudo-Obstrução Intestinal/patologia , Resultado do Tratamento , Modelos AnimaisRESUMO
The estimation of the contributions of UDP-glucuronosyl transferase (UGT) isoforms to the overall metabolism still suffers from technical difficulties due to limited information on enzyme levels in recombinant systems and specific inhibitors, unlike the case for cytochrome P450s (CYPs). The protein expression levels of UGT in both recombinant system microsomes (RM) and human liver microsomes (HLM) were quantified using liquid chromatography-tandem mass spectrometry, and the relative expression factor (REF) value of HLM to recombinant microsomes was estimated to evaluate the fractions of drug metabolism by a single UGT enzyme (fmUGT) of UGT substrates. The REF values of UGT1A1, UGT1A3, UGT1A9, UGT2B4, UGT2B7, and UGT2B17 were 0.228, 0.0714, 0.0665, 0.420, 0.118, and 0.0442, respectively. fmUGTs in HLM were estimated for several typical UGT substrates utilizing these values and metabolic clearances in RM. These values were comparable to the reported values estimated by various methods. This study provided useful information on REF values, which promote a robust estimation of fmUGT values for UGT substrates when evaluating the contribution of UGT isoforms to total metabolic clearance.
Assuntos
Glucuronosiltransferase , Isoenzimas , Humanos , Isoenzimas/metabolismo , Glucuronosiltransferase/metabolismo , Microssomos Hepáticos/metabolismo , Taxa de Depuração Metabólica , Cromatografia Líquida , Difosfato de Uridina/metabolismo , Glucuronídeos/metabolismoRESUMO
The simultaneous regulation of cancer cells and inflammatory immune cells in the tumor microenvironment (TME) can be an effective strategy in treating aggressive breast cancer types, such as triple-negative breast cancer (TNBC). Apurinic/apyrimidinic endonuclease 1/redox effector factor 1 (APE1/Ref-1) is a multi-functional nuclear protein that can be stimulated and then secreted. The extracellular APE1/Ref-1 causes a reduction in disulfide bonds in cytokine receptors, resulting in their conformational changes, thereby inhibiting inflammatory signaling. Furthermore, the secreted APE1/Ref-1 in response to acetylation has been shown to bind to a receptor for the advanced glycation end product (RAGE), initiating the apoptotic cell death of TNBC in vitro and in vivo. This study used PPTLS-APE1/Ref-1 in an adenovirus vector (Ad-PPTLS-APE1/Ref-1) for the constant expression of extracellular APE1/Ref-1, and our results demonstrated its dual function as an apoptotic initiator and inflammation regulator. Injecting MDA-MB 231 orthotopic xenografts with the Ad-PPTLS-APE1/Ref-1 inhibited tumor growth and development in response to acetylation. Moreover, Ad-PPTLS-APE1/Ref-1 generated reactive oxygen species (ROS), and tumor tissues derived from these xenografts exhibited apoptotic bodies. Compared to normal mice, a comparable ratio of anti- and pro-inflammatory cytokines was observed in the plasma of Ad-PPTLS-APE1/Ref-1-injected mice. Mechanistically, the disturbed cytokine receptor by reducing activity of PPTLS-APE1/Ref-1 inhibited inflammatory signaling leading to the inactivation of the p21-activated kinase 1-mediated signal transducer and activator of transcription 3/nuclear factor-κB axis in tumor tissues. These results suggest that the regulation of inflammatory signaling with adenoviral-mediated PPTLS-APE1/Ref-1 in tumors modulates the secretion of pro-inflammatory cytokines in TME, thereby inhibiting aggressive cancer cell progression, and could be considered as a promising and safe therapeutic strategy for treating TNBCs.
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Apoptose , DNA Liase (Sítios Apurínicos ou Apirimidínicos) , Neoplasias de Mama Triplo Negativas , Animais , Carcinogênese/genética , Transformação Celular Neoplásica , Citocinas/metabolismo , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Humanos , Inflamação/patologia , Camundongos , Oxirredução , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo , Microambiente TumoralRESUMO
BACKGROUND: Acute decompensated heart failure (ADHF) is the most common cause of hospital admission in patients over 65, with poorer outcomes demonstrated in rural versus metropolitan areas. The aim of this study was to compare the in-hospital and post-discharge management of ADHF patients admitted to rural versus metropolitan hospitals in Victoria. METHODS: Data from the Victorian Cardiac Outcomes Registry, Heart Failure (VCOR-HF) project was used. This was a prospective, observational, non-randomised study of consecutive patients admitted to participating hospitals in Victoria, Australia, with ADHF as their primary diagnosis over four 30-day periods during consecutive years. All patients were followed up for 30 days post discharge. RESULTS: 1,357 patients (1,260 metropolitan, 97 rural) were admitted to study hospitals with ADHF during the study periods. Cohorts were similar in age (average 76.87±13.12 yrs) and percentage of male gender (56.4% overall). Metropolitan patients were more likely to have diabetes (44.4% vs 34.0%, p=0.046), kidney disease (65.8% vs 37.1%, p<0.01) and anaemia (31.9% vs 19.6%, p=0.01). There was no significant difference in length of stay between metropolitan and rural patients (7.49 vs 6.37 days, p=0.12). There was no significant difference between metropolitan and rural patients in 30-day rehospitalisations (19.1% vs 11.6%, p=0.07, respectively) and all-cause 30-day mortality (8.2% vs 4.1%, p=0.15, respectively). Metropolitan patients were significantly more likely to have seen their general practitioner (GP) (68.1% vs 53.2%, p<0.01) or attend an outpatient clinic (35.9% vs 10.6%, p<0.01) by 30 days. There was no significant difference in number of days to follow-up of any kind between groups. Referrals to a heart failure home visiting program remained low overall (19.9%). CONCLUSION: There was no significant difference in 30-day rehospitalisations or mortality between patients admitted to rural versus metropolitan hospitals. Geographical discrepancies were noted in follow-up by 30 days, with significantly more metropolitan patients having seen a doctor by 30 days post-discharge. Overall follow-up rates remain suboptimal.
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Assistência ao Convalescente , Insuficiência Cardíaca , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Alta do Paciente , Estudos Prospectivos , Vitória/epidemiologiaRESUMO
The purpose of this study was to evaluate the potential of a newly modified cyclodextrin derivative, water-soluble ß-cyclodextrin-epichlorohydrin (ß-CD), as an effective drug carrier to enhance the poor solubility and bioavailability of galangin (GAL), a poorly water-soluble model drug. In this regard, inclusion complexes of GAL/ß-CDP were prepared. UV-VIS spectrophotometry, Fourier-transform infrared spectroscopy (FTIR), X-ray crystallography (XRD), zeta potential analysis, particle size analysis, field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM) were applied to characterize the synthesized GAL/ß-CD. Michigan Cancer Foundation-7 (MCF-7; human breast cancer cells) and rat embryo fibroblast (REF; normal cells) were employed to examine the in vitro cytotoxic effects of GAL/ß-CD using various parameters. The dye-based tests of MTT and crystal violet clearly exhibited that GAL/ß-CD-treated cells had a reduced proliferation rate, an influence that was not found in the normal cell line. The cells' death was found to follow apoptotic mechanisms, as revealed by the dye-based test of acridine orange/ethidium bromide (AO/EtBr), with the involvement of the mitochondria via caspase-3-mediated events, as manifested by the Rh 123 test. We also included a mouse model to examine possible in vivo toxic effects of GAL/ß-CD. It appears that the inclusion complex does not have a significant influence on normal cells, as indicated by serum levels of kidney and liver enzymatic markers, as well as thymic and splenic mass indices. A similar conclusion was reached on the histological level, as manifested by the absence of pathological alterations in the liver, kidney, thymus, spleen, heart, and lung.
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Neoplasias da Mama , beta-Ciclodextrinas , Animais , Neoplasias da Mama/tratamento farmacológico , Varredura Diferencial de Calorimetria , Portadores de Fármacos , Feminino , Flavonoides , Humanos , Camundongos , Ratos , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química , Difração de Raios X , beta-Ciclodextrinas/químicaRESUMO
Human malignant melanoma exhibits imbalances in redox status, leading to activation of many redox-sensitive signaling pathways. APE/Ref-1 is a multifunctional protein that serves as a redox chaperone that regulates many nuclear transcription factors and is an important mechanism in cancer cell survival of oxidative stress. Previous studies showed that APE/Ref-1 is a potential druggable target for melanoma therapy. In this study, we synthesized a novel APE/Ref-1 inhibitor, bis-cinnamoyl-1,12-dodecamethylenediamine (2). In a xenograft mouse model, compound 2 treatment (5 mg/kg) significantly inhibited tumor growth compared to the control group, with no significant systemic toxicity observed. We further synthesized compound 2 analogs to determine the structure-activity relationship based on their anti-melanoma activities. Among those, 4-hydroxyphenyl derivative (11) exhibited potent anti-melanoma activities and improved water solubility compared to its parental compound 2. The IC50 of compound 11 was found to be less than 0.1 µM. Compared to other known APE/Ref-1 inhibitors, compound 11 exhibited increased potency in inhibiting melanoma proliferation. As determined by luciferase reporter analyses, compound 2 was shown to effectively inhibit H2O2-activated AP-1 transcription activities. Targeting APE/Ref-1-mediated signaling using pharmaceutical inhibitors is a novel and effective strategy for melanoma treatment with potentially high impact.
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Hominidae , Melanoma , Animais , Cinamatos/farmacologia , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Hominidae/metabolismo , Humanos , Peróxido de Hidrogênio , Melanoma/tratamento farmacológico , CamundongosRESUMO
Glioblastoma multiforme (GBM) is considered to be one of the most serious version of primary malignant tumors. Temozolomide (TMZ), an anti-cancer drug, is the most common chemotherapeutic agent used for patients suffering from GBM. However, due to its inherent instability, short biological half-life, and dose-limiting characteristics, alternatives to TMZ have been sought. In this study, the TMZ-loaded PLGA nanoparticles were prepared by employing the emulsion solvent evaporation technique. The prepared TMZ-PLGA-NPs were characterized using FT-IR, zeta potential analyses, XRD pattern, particle size estimation, TEM, and FE-SEM observations. The virotherapy, being safe, selective, and effective in combating cancer, was employed, and TMZ-PLGA-NPs and oncolytic Newcastle Disease Virus (NDV) were co-administered for the purpose. An AMHA1-attenuated strain of NDV was propagated in chicken embryos, and the virus was titrated in Vero-slammed cells to determine the infective dose. The in vitro cytotoxic effects of the TMZ, NDV, and the TMZ-PLGA-NPs against the human glioblastoma cancer cell line, AMGM5, and the normal cell line of rat embryo fibroblasts (REFs) were evaluated. The synergistic effects of the nano-formulation and viral strain combined therapy was observed on the cell lines in MTT viability assays, together with the Chou-Talalay tests. The outcomes of the in vitro investigation revealed that the drug combinations of NDV and TMZ, as well as NDV and TMZ-PLGA-NPs exerted the synergistic enhancements of the antitumor activity on the AMGM5 cell lines. The effectiveness of both the mono, and combined treatments on the capability of AMGM5 cells to form colonies were also examined with crystal violet dyeing tests. The morphological features, and apoptotic reactions of the treated cells were investigated by utilizing the phase-contrast inverted microscopic examinations, and acridine orange/propidium iodide double-staining tests. Based on the current findings, the potential for the use of TMZ and NDV as part of a combination treatment of GBM is significant, and may work for patients suffering from GBM.
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Antineoplásicos , Neoplasias Encefálicas , Glioblastoma , Nanopartículas , Vírus Oncolíticos , Laranja de Acridina , Animais , Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Embrião de Galinha , Emulsões/uso terapêutico , Violeta Genciana , Glioblastoma/tratamento farmacológico , Humanos , Nanopartículas/química , Vírus da Doença de Newcastle , Propídio , Ratos , Solventes , Espectroscopia de Infravermelho com Transformada de Fourier , Temozolomida/farmacologiaRESUMO
Coronavirus disease 2019 (COVID-19) is largely threatening global public health, social stability, and economy. Efforts of the scientific community are turning to this global crisis and should present future preventative measures. With recent trends in polymer science that use plasma to activate and enhance the functionalities of polymer surfaces by surface etching, surface grafting, coating and activation combined with recent advances in understanding polymer-virus interactions at the nanoscale, it is promising to employ advanced plasma processing for smart antiviral applications. This trend article highlights the innovative and emerging directions and approaches in plasma-based surface engineering to create antiviral polymers. After introducing the unique features of plasma processing of polymers, novel plasma strategies that can be applied to engineer polymers with antiviral properties are presented and critically evaluated. The challenges and future perspectives of exploiting the unique plasma-specific effects to engineer smart polymers with virus-capture, virus-detection, virus-repelling, and/or virus-inactivation functionalities for biomedical applications are analysed and discussed.
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With a plethora of molecularly targeted agents under investigation in cancer, a clear need exists to understand which pathways can be targeted simultaneously with multiple agents to elicit a maximal killing effect on the tumour. Combination therapy provides the most promise in difficult to treat cancers such as pancreatic. Ref-1 is a multifunctional protein with a role in redox signalling that activates transcription factors such as NF-κB, AP-1, HIF-1α and STAT3. Formerly, we have demonstrated that dual targeting of Ref-1 (redox factor-1) and STAT3 is synergistic and decreases cell viability in pancreatic cancer cells. Data presented here extensively expands upon this work and provides further insights into the relationship of STAT3 and Ref-1 in multiple cancer types. Using targeted small molecule inhibitors, Ref-1 redox signalling was blocked along with STAT3 activation, and tumour growth evaluated in the presence and absence of the relevant tumour microenvironment. Our study utilized qPCR, cytotoxicity and in vivo analysis of tumour and cancer-associated fibroblasts (CAF) response to determine the synergy of Ref-1 and STAT3 inhibitors. Overall, pancreatic tumours grown in the presence of CAFs were sensitized to the combination of STAT3 and Ref-1 inhibition in vivo. In vitro bladder and pancreatic cancer demonstrated the most synergistic responses. By disabling both of these important pathways, this combination therapy has the capacity to hinder crosstalk between the tumour and its microenvironment, leading to improved tumour response.
Assuntos
DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Fator de Transcrição STAT3/metabolismo , Animais , Benzofuranos/farmacologia , Western Blotting , Linhagem Celular Tumoral , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , Células HCT116 , Humanos , Imuno-Histoquímica , Camundongos , Naftoquinonas/farmacologia , Nitrilas , Neoplasias Pancreáticas/genética , Pirazóis/farmacologia , Pirimidinas , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição STAT3/genética , Microambiente Tumoral/efeitos dos fármacosRESUMO
Perturbation of lignin biosynthesis often results in severe growth and developmental defects in plants, which imposes practical limitations to genetic enhancement of lignocellulosic biomass for biofuel production. Currently, little information is known about the cellular and genetic mechanisms of this important phenomenon. Here we show that defects in both cell division and cell expansion underlie the dwarfism of an Arabidopsis lignin mutant ref8, and report the identification of a GROWTH INHIBITION RELIEVED 1 (GIR1) gene from a suppressor screen. GIR1 encodes an importin-beta-like protein required for the nuclear import of MYB4, a transcriptional repressor of phenylpropanoid metabolism. Disruption of GIR1 and MYB4 similarly alleviates the cellular defects and growth inhibition in ref8, suggesting that the growth rescue effect of gir1 is likely due to compromised MYB4 transport and function. Importantly, the phenylpropanoid perturbation is not alleviated in gir1 ref8 and myb4 ref8, suggesting that the function of MYB4 in growth inhibition of lignin-modified plants is likely to be distinct from its known role in transcriptional regulation of phenylpropanoid biosynthetic genes. This study also provides evidence that lignin-modification-induced dwarfism is not merely due to compromised water transport brought about by lignin deficiency, as gir1 has no effect on the growth inhibition of other lignin mutants that show the collapsed xylem phenotype.