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1.
Cancers (Basel) ; 15(15)2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37568630

RESUMO

Manganese(III) porphyrin MnTnBuOE-2-PyP5+ (MnBuOE, BMX-001) is a third-generation redox-active cationic substituted pyridylporphyrin-based drug with a good safety/toxicity profile that has been studied in several types of cancer. It is currently in four phase I/II clinical trials on patients suffering from glioma, head and neck cancer, anal squamous cell carcinoma and multiple brain metastases. There is yet an insufficient understanding of the impact of MnBuOE on lung cancer. Therefore, this study aims to fill this gap by demonstrating the effects of MnBuOE on non-small cell lung cancer (NSCLC) A549 and H1975 cell lines. The cytotoxicity of MnBuOE alone or combined with cisplatin was evaluated by crystal violet (CV) and/or 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulphophenyl)-2H-Tetrazolium (MTS) reduction assays. Intracellular ROS levels were assessed using two fluorescent probes. Furthermore, the impact of MnBuOE alone or in combination with cisplatin on collective cell migration, individual chemotactic migration and chemoinvasion was assessed using the wound-healing and transwell assays. The expression of genes related to migration and invasion was assessed through RT-qPCR. While MnBuOE alone decreased H1975 cell viability at high concentrations, when combined with cisplatin it markedly reduced the viability of the more invasive H1975 cell line but not of A549 cell line. However, MnBuOE alone significantly decreased the migration of both cell lines. The anti-migratory effect was more pronounced when MnBuOE was combined with cisplatin. Finally, MnBuOE alone or combined with cisplatin significantly reduced cell invasion. MnBuOE alone or combined with cisplatin downregulated MMP2, MMP9, VIM, EGFR and VEGFA and upregulated CDH1 in both cell lines. Overall, our data demonstrate the anti-metastatic potential of MnBuOE for the treatment of NSCLC.

2.
Clin Drug Investig ; 43(9): 691-698, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37479867

RESUMO

BACKGROUND AND OBJECTIVES: Deescalation strategies omitting anthracyclines (AC) have been explored in early human epidermal growth factor receptor 2-positive breast cancer (HER2+ EBC), showing similar efficacy regarding pathological complete response (pCR) and long-term outcomes as AC-containing regimens. The standard treatment for this tumor subtype is based on chemotherapy and dual HER2 blockade with trastuzumab and pertuzumab, with AC-containing regimens remaining a frequent option for these patients, even in non-high-risk cases. The primary aim of this study was to assess and compare the effectiveness of neoadjuvant regimens with and without AC used in the treatment of HER2+ EBC in the clinical practice according to the pCR achieved with each. METHODS: This retrospective multicentric study included patients with HER2+ EBC from Portuguese, Spanish, and Chilean hospitals (January 2018-December 2021). Patients receiving neoadjuvant therapy (NAT) with dual HER2 blockade (trastuzumab and pertuzumab), followed by surgery, were included. Statistical analysis used chi-squared/Fisher's exact test for associations, multivariate logistic regression for pCR, and Kaplan-Meier method for event-free survival (EFS). IBM SPSS Statistics 29.0 analyzed the data. RESULTS: The study included 371 patients from eight hospitals. Among them, 237 received sequential AC and taxane-based chemotherapy with 4 cycles of trastuzumab and pertuzumab, while 134 received 6 cycles of TCHP (docetaxel, carboplatinum, trastuzumab, and pertuzumab). The average age of the patients was 52.8 years and 52.7 years, respectively. Omitting AC from the neoadjuvant approach did not preclude achieving pCR [p = 0.246, 95% confidence interval (CI) 0.235-0.257] and was safe regardless of patient characteristics. Relapse rates were 6.8% (16 patients) in the AC group and 4.5% (6 patients) in the TCHP group. Over a median follow-up of 2.9 years, the estimated 3-year EFS was 92.5% in the AC group and 95.4% in the TCHP group (hazard ratio 0.602, 95% CI 0.234-1.547, p = 0.292, favoring TCHP). CONCLUSION: This study reports real-world evidence showing similar pCR and EFS outcomes with treatment regimens with and without AC and raises awareness of possible overtreatment and long-term toxicity in some patients with HER2+ EBC with the use of AC.


Assuntos
Neoplasias da Mama , Humanos , Pessoa de Meia-Idade , Feminino , Neoplasias da Mama/tratamento farmacológico , Terapia Neoadjuvante , Antraciclinas/uso terapêutico , Estudos Retrospectivos , Recidiva Local de Neoplasia , Trastuzumab/uso terapêutico , Antibióticos Antineoplásicos
3.
Foods ; 12(14)2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37509834

RESUMO

The concept of "functional foods" converges topics such as diet, food, health, and disease [...].

4.
Mol Nutr Food Res ; 67(3): e2200581, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36415106

RESUMO

SCOPE: Epidemiological evidence associates the consumption of cruciferous vegetables with reduced risk of several cancers, including renal cell carcinoma. Erucin can be generated by in vivo reduction of sulforaphane or by enzymatic hydrolysis of glucoerucin. Contrarily to sulforaphane, only limited studies have addressed the anticancer properties of erucin. This study aims at evaluating the impact of erucin on renal cell biology. METHODS AND RESULTS: The effects of erucin were assessed in 786-O and Vero-E6 cells, representative of human renal cancer and non- cancer kidney cells, respectively. Erucin induced a concentration-dependent decrease in cell viability and cell cycle arrest at G2/Mitosis. In Vero-E6 cells erucin modestly reduced intracellular reactive oxygen species levels while in 786-O no effects were detected. After erucin treatment, both cell lines revealed altered morphology, with a concentration-dependent change from an elongated shape towards a smaller round conformation. Moreover, erucin affected cell adhesion and strongly altered the tubulin network structure and specifically microtubule polymerization. These results are in line with the observed decrease in collective and single cell migration and G2/Mitosis arrest. CONCLUSIONS: Overall, erucin may have a beneficial impact in reducing the motility of renal cancer cells. Our results contribute to explore possible dietary approaches for secondary/tertiary renal cancer chemoprevention.


Assuntos
Neoplasias Renais , Tubulina (Proteína) , Humanos , Polimerização , Isotiocianatos/farmacologia , Rim/metabolismo , Movimento Celular , Apoptose
5.
Antioxidants (Basel) ; 11(11)2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36358570

RESUMO

The manganese(III) porphyrin MnTnHex-2-PyP5+ (MnTnHex) is a potent superoxide dismutase mimic and modulator of redox-based transcriptional activity that has been studied in the context of different human disease models, including cancer. Nevertheless, for lung cancer, hardly any information is available. Thus, the present work aims to fill this gap and reports the effects of MnTnHex in non-small cell lung cancer (NSCLC) cells, more specifically, A549 and H1975 cells, in vitro. Both cell lines were initially characterized in terms of innate levels of catalase, glutathione peroxidase 1, and peroxiredoxins 1 and 2. To assess the effect of MnTnHex in NSCLC, alone or in combination with cisplatin, endpoints related to the cell viability, cell cycle distribution, cell motility, and characterization of the volatile carbonyl compounds (VCCs) generated in the extracellular medium (i.e., exometabolome) were addressed. The results show that MnTnHex as a single drug markedly reduced the viability of both NSCLC cell lines, with some IC50 values reaching sub-micromolar levels. This redox-active drug also altered the cell cycle distribution, induced cell death, and increased the cytotoxicity pattern of cisplatin. MnTnHex also reduced collective cell migration. Finally, the metabolomics study revealed an increase in the levels of a few VCCs associated with oxidative stress in MnTnHex-treated cells. Altogether these results suggest the therapeutic potential of MnTnHex to be further explored, either alone or in combination therapy with cisplatin, in NSCLC.

6.
Curr Med Res Opin ; 38(8): 1379-1382, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35770865

RESUMO

Tumor-infiltrating lymphocytes (TILs) have shown prognostic value in breast cancer. This study evaluated the TILs scores in 186 Portuguese patients diagnosed with early breast cancer, with special focus on HER2 subtype. Stromal TILs were scored on the core needle biopsies, as well as in the resected specimen in HER2+ patients submitted to neoadjuvant treatment with trastuzumab and pertuzumab. TILs were higher in tumors with negative hormone receptor status and HER2 amplifications, and in triple-negative breast cancer. In HER2+ patients treated with dual anti-HER neoadjuvant therapy, the TILs score on the surgical specimen was generally lower than in the biopsy.


Assuntos
Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/patologia , Feminino , Humanos , Linfócitos do Interstício Tumoral/patologia , Terapia Neoadjuvante , Portugal , Prognóstico , Receptor ErbB-2 , Neoplasias de Mama Triplo Negativas/tratamento farmacológico
7.
Foods ; 11(7)2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35407148

RESUMO

Kidney diseases constitute a worldwide public health problem, contributing to morbidity and mortality. The present study aimed to provide an overview of the published data regarding the potential beneficial effects of polyphenols on major kidney diseases, namely acute kidney injury, chronic kidney disease, diabetic nephropathy, renal cancer, and drug-induced nephrotoxicity. This study consists of a bibliographical review including in vitro and in vivo studies dealing with the effects of individual compounds. An analysis of the polyphenol metabolome in human urine was also conducted to estimate those compounds that are most likely to be responsible for the kidney protective effects of polyphenols. The biological effects of polyphenols can be highly attributed to the modulation of specific signaling cascades including those involved in oxidative stress responses, anti-inflammation processes, and apoptosis. There is increasing evidence that polyphenols afford great potential in renal disease protection. However, this evidence (especially when in vitro studies are involved) should be considered with caution before its clinical translation, particularly due to the unfavorable pharmacokinetics and extensive metabolization that polyphenols undergo in the human body. Future research should consider polyphenols and their metabolites that indeed reach kidney tissues.

8.
Transl Lung Cancer Res ; 10(6): 2698-2714, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34295671

RESUMO

Lung cancer (LC) is the leading cause of cancer deaths worldwide, being non-small lung cancer (NSCLC) sub-types the most prevalent. Since most LC cases are only detected during the last stage of the disease the high mortality rate is strongly associated with metastases. For this reason, the migratory and invasive capacity of these cancer cells as well as the mechanisms involved have long been studied to uncover novel strategies to prevent metastases and improve the patients' prognosis. This narrative review provides an overview of the main in vitro migration and invasion assays employed in NSCLC research. While several methods have been developed, experiments using conventional cell culture models prevailed, specifically the wound-healing and the transwell migration and invasion assays. Moreover, it is provided herewith a summary of the available information concerning chemical contaminants that may promote the migratory/invasive properties of NSCLC cells in vitro, shedding some light on possible LC risk factors. Most of the reported agents with pro-migration/invasion effects derive from cigarette smoking [e.g., Benzo(a)pyrene and cadmium] and air pollution. This review further presents several studies in which different dietary/plant-derived compounds demonstrated to impair migration/invasion processes in NSCLC cells in vitro. These chemicals that have been proposed as anti-migratory consisted mainly of natural bioactive substances, including polyphenols non-flavonoids, flavonoids, bibenzyls, terpenes, alkaloids, and steroids. Some of these compounds may eventually represent novel therapeutic strategies to be considered in the future to prevent metastasis formation in LC, which highlights the need for additional in vitro methodologies that more closely resemble the in vivo tumor microenvironment and cancer cell interactions. These studies along with adequate in vivo models should be further explored as proof of concept for the most promising compounds.

9.
Antioxidants (Basel) ; 9(6)2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32599967

RESUMO

Elevated expression levels of the apurinic/apyrimidinic endonuclease 1 (APE1) have been correlated with the more aggressive phenotypes and poor prognosis of non-small cell lung cancer (NSCLC). This study aimed to assess the impact of the inhibition of the redox function of APE1 with E3330 either alone or in combination with cisplatin in NSCLC cells. For this purpose, complementary endpoints focusing on cell viability, apoptosis, cell cycle distribution, and migration/invasion were studied. Cisplatin decreased the viability of H1975 cells in a time- and concentration-dependent manner, with IC50 values of 9.6 µM for crystal violet assay and 15.9 µM for 3-(4,5-Dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay. E3330 was clearly cytotoxic for concentrations above 30 µM. The co-incubation of E3330 and cisplatin significantly decreased cell viability compared to cisplatin alone. Regarding cell cycle distribution, cisplatin led to an increase in sub-G1, whereas the co-treatment with E3330 did not change this profile, which was then confirmed in terms of % apoptotic cells. In addition, the combination of E3330 and cisplatin at low concentrations decreased collective and chemotactic migration, and also chemoinvasion, by reducing these capabilities up to 20%. Overall, these results point to E3330 as a promising compound to boost cisplatin therapy that warrants further investigation in NSCLC.

10.
Biomolecules ; 10(1)2020 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-31963771

RESUMO

Medicinal plants are important sources of new bioactive compounds with potential anticancer activity. Parvifloron D (ParvD) is an abietane diterpenoid, isolated in high amounts from Plectranthus ecklonii Benth. Previous reports have suggested potential therapeutic properties for ParvD. ParvD has shown pro-apoptotic and cytotoxic effects in leukemia and melanoma cell lines. However, to the best of our knowledge, there are no studies in triple-negative breast cancer (TNBC) models. TNBC is a breast cancer subtype characterized by an aggressive behavior with poor clinical outcomes and weak overall therapeutic responses to the current treatment options. This work aimed at evaluating the anticancer effect of ParvD in MDA-MB-231 cells, a model of human TNBC. To obtain sufficient amounts of purified ParvD the efficiency of several extraction methods was compared. ParvD (0.1-10 µM) decreased cell viability in a concentration-dependent manner. Treatment with ParvD (5 µM) significantly increased the percentage of apoptotic nuclei and exposure to 3 µM ParvD increased the sub-G1 population. Since altered cell adherence, migration, and invasion are determinant processes for the formation of metastases, the effect of ParvD on these cellular processes was tested. Although treatment with ParvD (1 µM) had no effect on cell-substrate attachment, ParvD (1 µM) significantly reduced cell chemotaxis and invasion. This is the first report describing the proapoptotic effect of ParvD in TNBC cells. Moreover, for the first time we have shown that ParvD reduces cell motility, unraveling potential anti-metastatic properties.


Assuntos
Abietanos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Abietanos/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Plectranthus/química , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia
11.
Antioxidants (Basel) ; 8(10)2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31627290

RESUMO

Clear-cell renal carcinoma (ccRCC) is the most common type of renal cancer. The importance of oxidative stress in the context of this disease has been described, although there is only little information concerning the role of superoxide dismutase (SOD) enzymes. The importance of SOD in different pathological conditions promoted the development of SOD mimics (SODm). As such, manganese(III) porphyrins can mimic the natural SOD enzymes and scavenge different reactive oxygen species (ROS), thus modulating the cellular redox status. In this study, the exposure of 786-O human renal cancer cells to MnTnHex-2-PyP5+ (MnP), a very promising SODm, led to a concentration and time-dependent decrease in cell viability and in the cell proliferation indices, as well as to an increase in apoptosis. No relevant effects in terms of micronuclei formation were observed. Moreover, the exposure to MnP resulted in a concentration-dependent increase in intracellular ROS, presumably due to the generation of H2O2 by the inherent redox mechanisms of MnP, along with the limited ability of cancer cells to detoxify this species. Although the MnP treatment did not result in a reduction in the collective cell migration, a significant decrease in chemotactic migration was observed. Overall, these results suggest that MnP has a beneficial impact on reducing renal cancer cell viability and migration and warrant further studies regarding SODm-based therapeutic strategies against human renal cancer.

12.
Redox Biol ; 20: 367-378, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30408752

RESUMO

Manganese(III) porphyrins (MnPs) are superoxide dismutase (SOD) mimics with demonstrated beneficial effects in cancer treatment in combination with chemo- and radiotherapy regimens. Despite the ongoing clinical trials, little is known about the effect of MnPs on metastasis, being therefore essential to understand how MnPs affect this process. In the present work, the impact of the MnP MnTnHex-2-PyP5+ in metastasis-related processes was assessed in breast cancer cells (MCF-7 and MDA-MB-231), alone or in combination with doxorubicin (dox). The co-treatment of cells with non-cytotoxic concentrations of MnP and dox altered intracellular ROS, increasing H2O2. While MnP alone did not modify cell migration, the co-exposure led to a reduction in collective cell migration and chemotaxis. In addition, the MnP reduced the dox-induced increase in random migration of MDA-MB-231 cells. Treatment with either MnP or dox decreased the proteolytic invasion of MDA-MB-231 cells, although the effect was more pronounced upon co-exposure with both compounds. Moreover, to explore the cellular mechanisms underlying the observed effects, cell adhesion, spreading, focal adhesions, and NF-κB activation were also studied. Although differential effects were observed according to the endpoints analysed, overall, the alterations induced by MnP in dox-treated cells were consistent with a therapeutically favorable outcome.


Assuntos
Neoplasias da Mama/metabolismo , Movimento Celular/efeitos dos fármacos , Metaloporfirinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Adesão Celular/efeitos dos fármacos , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Espaço Intracelular/metabolismo , Metaloporfirinas/química , Estrutura Molecular , NF-kappa B/metabolismo
13.
Redox Biol ; 13: 94-162, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28577489

RESUMO

The European Cooperation in Science and Technology (COST) provides an ideal framework to establish multi-disciplinary research networks. COST Action BM1203 (EU-ROS) represents a consortium of researchers from different disciplines who are dedicated to providing new insights and tools for better understanding redox biology and medicine and, in the long run, to finding new therapeutic strategies to target dysregulated redox processes in various diseases. This report highlights the major achievements of EU-ROS as well as research updates and new perspectives arising from its members. The EU-ROS consortium comprised more than 140 active members who worked together for four years on the topics briefly described below. The formation of reactive oxygen and nitrogen species (RONS) is an established hallmark of our aerobic environment and metabolism but RONS also act as messengers via redox regulation of essential cellular processes. The fact that many diseases have been found to be associated with oxidative stress established the theory of oxidative stress as a trigger of diseases that can be corrected by antioxidant therapy. However, while experimental studies support this thesis, clinical studies still generate controversial results, due to complex pathophysiology of oxidative stress in humans. For future improvement of antioxidant therapy and better understanding of redox-associated disease progression detailed knowledge on the sources and targets of RONS formation and discrimination of their detrimental or beneficial roles is required. In order to advance this important area of biology and medicine, highly synergistic approaches combining a variety of diverse and contrasting disciplines are needed.


Assuntos
Cooperação Internacional , Espécies Reativas de Oxigênio/metabolismo , Animais , União Europeia , Humanos , Biologia Molecular/organização & administração , Biologia Molecular/tendências , Oxirredução , Espécies Reativas de Oxigênio/química , Transdução de Sinais , Sociedades Científicas
14.
Chem Biol Drug Des ; 90(4): 561-571, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28303665

RESUMO

The human apurinic/apyrimidinic endonuclease 1 (APE1) is an ubiquitous multifunctional DNA repair enzyme and a redox signalling protein. Our work addressed the inhibition of APE1 redox function using E3330, as single agent or in combination with docetaxel (DTX), in human breast cancer MDA-MB-231 cells. E3330 decreased the colony formation of DTX-treated cells. In addition, E3330 alone significantly reduced the collective cell migration as assessed by the wound-healing assay, whereas the combined treatment decreased chemoinvasion. These results suggest that the inhibition of APE1 redox function might have therapeutic potential by modulating cell migration and invasion in metastatic breast cancer.


Assuntos
Antineoplásicos/farmacologia , Benzoquinonas/farmacologia , Neoplasias da Mama/tratamento farmacológico , Movimento Celular/efeitos dos fármacos , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/antagonistas & inibidores , Invasividade Neoplásica/prevenção & controle , Propionatos/farmacologia , Taxoides/farmacologia , Mama/efeitos dos fármacos , Mama/metabolismo , Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Docetaxel , Feminino , Humanos , Invasividade Neoplásica/patologia , Oxirredução/efeitos dos fármacos
15.
Chem Biol Drug Des ; 88(6): 915-925, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27450574

RESUMO

The DNA repair activity of human apurinic/apyrimidinic endonuclease 1 (APE1) has been recognized as a promising target for the development of small-molecule inhibitors to be used in combination with anticancer agents. In an attempt to identify novel inhibitors of APE1, we present a structure-based virtual screening (SBVS) study based on molecular docking analysis of the compounds of NCI database using the GOLD 5.1.0 (Genetic Optimization for Ligand Docking) suite of programs. Compounds selected in this screening were tested with a fluorescence-based APE1 endonuclease activity assay. Two compounds (37 and 41) were able to inhibit the multifunctional enzyme APE1 in the micromolar range, while compound 22 showed inhibitory effects at nanomolar concentrations. These results were confirmed by a plasmid DNA nicking assay. In addition, the potential APE1 inhibitors did not affect the cell viability of non-tumor MCF10A cells. Overall, compounds 22, 37, and 41 appear to be important scaffolds for the design of novel APE1 inhibitors and this study highlights the relevance of in silico-based approaches as valuable tools in drug discovery.


Assuntos
Reparo do DNA , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/antagonistas & inibidores , Inibidores Enzimáticos/química , Linhagem Celular Tumoral , Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Humanos , Concentração Inibidora 50 , Ligantes , Simulação de Acoplamento Molecular , Proteínas Recombinantes/efeitos dos fármacos , Espectrometria de Fluorescência
16.
Food Chem Toxicol ; 87: 65-76, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26627377

RESUMO

Ochratoxin A (OTA) is a well-known nephrotoxic and potential carcinogenic agent but no consensus about the molecular mechanisms underlying its deleterious effects has been reached yet. The aim of this study is to integrate several endpoints concerning OTA-induced toxicological effects in Vero kidney cells in order to obtain additional mechanistic data, especially regarding the influence of reactive oxygen species (ROS). One innovative aspect of this work is the use of the superoxide dismutase mimic (SODm) MnTnHex-2-PyP as a mechanistic tool to clarify the involvement of oxidative stress in OTA toxicity. The results showed concentration and time-dependent cytotoxic effects of OTA (crystal violet, neutral red and LDH leakage assays). While the SODm mildly increased cell viability, trolox and ascorbic acid had no effect with regards to this endpoint. OTA induced micronuclei formation. Using the FPG modified comet assay, OTA modestly increased the % of DNA in tail, revealing the presence of oxidative DNA lesions. This mycotoxin increased apoptosis, which was attenuated by SODm. In addition, the SODm decreased the ROS accumulation observed in DHE assay. Taken together, our data suggest that ROS partially contribute to the cytotoxicity and genotoxicity of OTA, although other mechanisms may be relevant in OTA-induced deleterious effects.


Assuntos
Rim/citologia , Rim/efeitos dos fármacos , Ocratoxinas/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Animais , Apoptose , Ciclo Celular , Sobrevivência Celular , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Estrutura Molecular , Testes de Mutagenicidade , Ocratoxinas/administração & dosagem , Ocratoxinas/química , Células Vero
17.
Mutat Res Genet Toxicol Environ Mutagen ; 757(2): 140-7, 2013 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-23958474

RESUMO

Pharmacological inhibition of DNA repair is a promising approach to increase the effectiveness of anticancer drugs. The chemotherapeutic drug doxorubicin (Dox) may act, in part, by causing oxidative DNA damage. The base excision repair (BER) pathway effects the repair of many DNA lesions induced by reactive oxygen species (ROS). Methoxyamine (MX) is an indirect inhibitor of apurinic/apyrimidinic endonuclease 1 (APE1), a multifunctional BER protein. We have evaluated the effects of MX on the cytotoxicity and genotoxicity of Dox in MDA-MB-231 metastatic breast cancer cells. MX has little effects on the viability and proliferation of Dox-treated cells. However, as assessed by the cytokinesis-block micronucleus assay (CBMN), MX caused a significant 1.4-fold increase (P<0.05) in the frequency of micronucleated binucleated cells induced by Dox, and also altered the distribution of the numbers of micronuclei. The fluorescence probe dihydroethidium (DHE) indicated little production of ROS by Dox. Overall, our results suggest differential outcomes for the inhibition of APE1 activity in breast cancer cells exposed to Dox, with a sensitizing effect observed for genotoxicity but not for cytotoxicity.


Assuntos
Antibióticos Antineoplásicos/farmacocinética , Neoplasias da Mama/metabolismo , Dano ao DNA , Reparo do DNA/efeitos dos fármacos , Doxorrubicina/farmacologia , Hidroxilaminas/farmacologia , Antibióticos Antineoplásicos/agonistas , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Citocinese/efeitos dos fármacos , Citotoxinas/agonistas , Citotoxinas/farmacologia , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/antagonistas & inibidores , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Doxorrubicina/agonistas , Sinergismo Farmacológico , Feminino , Humanos , Hidroxilaminas/agonistas , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo
18.
Phytochemistry ; 78: 81-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22516741

RESUMO

Upon insect herbivory, plants can release blends of volatile organic compounds (VOCs) that modify herbivore and natural enemy behaviour. We have shown recently that cotton, Gossypium hirsutum, emits a blend of defence VOCs that repels the cotton aphid, Aphis gossypii, upon herbivory by this notorious crop pest, including (Z)-3-hexenyl acetate, (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), methyl salicylate and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene (TMTT). In this study, we investigated changes in the defence VOC profile of G. hirsutum induced by the naturally-occurring plant elicitor cis-jasmone (CJ) and whether these changes modify the behaviour of A. gossypii. In four-arm olfactometer assays, VOCs from untreated plants were significantly attractive (P<0.05), whilst VOCs from CJ-treated plants were significantly repellent (P<0.05). The VOCs induced by CJ appeared to comprise (Z)-3-hexenyl acetate, DMNT, methyl salicylate and TMTT. In quantitative VOC collection studies, sustained release of DMNT and TMTT was observed in CJ-treated plants over a period of five days, with levels becoming statistically significantly higher than for control treated plants on the fifth day in most cases. Despite earlier indications, no statistically significant differences were observed in levels of (Z)-3-hexenyl acetate or methyl salicylate between CJ and control treatments on any day. Furthermore, DMNT and TMTT emissions from CJ-treated plants were further enhanced by subsequent addition of A. gossypii. CJ treatment induced statistically significantly higher DMNT and TMTT expression levels as early as day three, when A. gossypii was present. The results in this study show that CJ can induce the production of A. gossypii-induced VOCs from G. hirsutum, with potential for deployment in novel crop protection strategies.


Assuntos
Afídeos/fisiologia , Ciclopentanos/metabolismo , Gossypium/química , Herbivoria , Oxilipinas/metabolismo , Compostos Orgânicos Voláteis/isolamento & purificação , Acetatos/isolamento & purificação , Alcenos/isolamento & purificação , Animais , Afídeos/efeitos dos fármacos , Ciclopentanos/análise , Gossypium/metabolismo , Estrutura Molecular , Oxilipinas/análise , Salicilatos/isolamento & purificação , Estereoisomerismo , Terpenos/isolamento & purificação , Compostos Orgânicos Voláteis/análise
19.
J Chem Ecol ; 37(7): 741-50, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21671083

RESUMO

The cotton aphid, Aphis gossypii (Homoptera: Aphididae), is increasing in importance as a pest worldwide since the introduction of Bt-cotton, which controls lepidopteran but not homopteran pests. The chemical ecology of interactions between cotton, Gossypium hirsutum (Malvaceae), A. gossypii, and the predatory lacewing Chrysoperla lucasina (Neuroptera: Chrysopidae), was investigated with a view to providing new pest management strategies. Behavioral tests using a four-arm (Pettersson) olfactometer showed that alate A. gossypii spent significantly more time in the presence of odor from uninfested cotton seedlings compared to clean air, but significantly less time in the presence of odor from A. gossypii infested plants. A. gossypii also spent significantly more time in the presence of headspace samples of volatile organic compounds (VOCs) obtained from uninfested cotton seedlings, but significantly less time with those from A. gossypii infested plants. VOCs from uninfested and A. gossypii infested cotton seedlings were analyzed by gas chromatography (GC) and coupled GC-mass spectrometry (GC-MS), leading to the identification of (Z)-3-hexenyl acetate, (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), methyl salicylate, and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene (TMTT), which were produced in larger amounts from A. gossypii infested plants compared to uninfested plants. In behavioral tests, A. gossypii spent significantly more time in the control (solvent) arms when presented with a synthetic blend of these four compounds, with and without the presence of VOCs from uninfested cotton. Coupled GC-electroantennogram (EAG) recordings with the lacewing C. lucasina showed significant antennal responses to VOCs from A. gossypii infested cotton, suggesting they have a role in indirect defense and indicating a likely behavioral role for these compounds for the predator as well as the aphid.


Assuntos
Afídeos/fisiologia , Comportamento Animal/fisiologia , Gossypium/química , Feromônios/isolamento & purificação , Acetatos/isolamento & purificação , Alcenos/isolamento & purificação , Animais , Cromatografia Gasosa-Espectrometria de Massas , Gossypium/fisiologia , Terpenos/isolamento & purificação , Compostos Orgânicos Voláteis/isolamento & purificação
20.
Rev. saúde pública ; 39(1): 122-128, fev. 2005. tab
Artigo em Português | LILACS | ID: lil-391881

RESUMO

OBJETIVO: A tuberculose é uma das maiores causas de mortalidade no mundo, porém seus efeitos econômicos são pouco conhecidos. O objetivo do estudo foi o de estimar os custos do tratamento e prevenção da tuberculose para o sistema de saúde (público e privado) e para as famílias. MÉTODOS: O estudo foi realizado no município de Salvador, BA, em 1999. Os dados para estimação dos custos para o sistema de saúde foram coletados nas secretarias de saúde, centros de saúde e em uma entidade filantrópica. Os custos públicos e privados foram estimados pela metodologia da contabilidade de custos. Os dados de custos para as famílias foram coletados por meio de questionários e incluem despesas com transporte, alimentação e outros, bem como as perdas de renda associadas à doença. RESULTADOS: O custo médio para tratamento de um caso novo de tuberculose foi de aproximadamente R$186,00 (US$103); para o tratamento de um paciente multiresistente o custo foi 27 vezes mais alto. Os custos para o serviço público corresponderam a 65 por cento em internações, 32 por cento em tratamento e apenas 3 por cento em prevenção. As famílias comprometeram cerca de 33 por cento da sua renda com despesas relacionadas a tuberculose. CONCLUSÕES: Apesar do fato das famílias não terem que pagar por medicamentos e tratamento, dado que este serviço é oferecido pelo Estado, os custos familiares ligados a perda de rendimentos devido a doença foram muito elevados. A proporção utilizada em prevenção pelo serviço público é pequena. Um maior investimento em campanhas de prevenção poderia não somente diminuir o número de casos, mas também, levar a um diagnósticos precoce, diminuindo os custos associados à hospitalização. A falta de um sistema integrado de custos não permite a visualização dos custos nos diversos setores.


Assuntos
Efeitos Psicossociais da Doença , Custos de Cuidados de Saúde , Tuberculose/economia
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