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1.
Lett Appl Microbiol ; 77(5)2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38658187

RESUMO

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 Microbiana
3.
Clin Transl Oncol ; 24(11): 2231-2240, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35852680

RESUMO

PURPOSE: Although lorlatinib, the third generation of echinoderm microtubule protein 4-anaplastic lymphoma kinase (EML4-ALK) tyrosine kinase inhibitor (TKI), overcame the previous generation ALK-TKIs' drug resistance problems, but the mechanism of lorlatinib resistance remained unclear. Furthermore, optimal chemotherapy for lorlatinib-resistant non-small cell lung cancer (NSCLC) patients was still unknown. METHODS: A lorlatinib-resistant NSCLC cell line SNU-2535LR was generated by gradually increasing dose of lorlatinib to crizotinib-resistant cell line SNU-2535 in vitro. To study the resistance mechanism of SNU-2535LR cells, we applied CCK-8 assay to detect the sensitivity of crizotinib and the reverse effect of APR-246, a p53 activator, on lorlatinib-induced resistance and different chemotherapy drugs to SNU-2535LR cells. We also detected the expressions of EML4-ALK-related proteins of SNU-2535LR cells via western blot.Please confirm that author names have been identified correctly and are presented in the right order.Dear Editor:     I have carefully confirmed that the author names have been identified correctly and are presented in right order.Thank you very much!                                                                     Your sincerely BoXie RESULTS: The sensitivity of SNU-2535LR cells to lorlatinib was decreased significantly than that of SNU-2535 cells. EML4-ALK fusion was decreased both at protein level and DNA level in SNU-2535LR cells. More interesting, the crizotinib-resistant mutation ALK p.G1269A disappeared, while new TP53 mutation emerged in SNU-2535LR cells. APR-246 can reverse the lorlatinib resistance in SNU-2535LR cells, with a reversal index of 4.768. Compared with SNU-2535 cells, the sensitivity of SNU-2535LR cells to gemcitabine, docetaxel and paclitaxel was significantly increased (P < 0.05), but decreased to cisplatin (P < 0.05). CONCLUSION: This study demonstrated that the combination of p53 protein agonist and lorlatinib may provide a new therapeutic strategy for NSCLC patients with lorlatinib resistance and TP53 mutation. Furthermore, the results also provide guidance for selecting optimal chemo-regimens for NSCLC patients after ALK-TKIs failure.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Aminopiridinas , Quinase do Linfoma Anaplásico/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular , Cisplatino/uso terapêutico , Crizotinibe/uso terapêutico , Docetaxel/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Lactamas , Lactamas Macrocíclicas/farmacologia , Lactamas Macrocíclicas/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Proteínas dos Microtúbulos/genética , Mutação , Paclitaxel/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Pirazóis , Proteína Supressora de Tumor p53/genética
4.
J Comput Chem ; 42(13): 897-907, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33713492

RESUMO

SARS-CoV and SARS-CoV-2 belong to the subfamily Coronaviridae and infect humans, they are constituted by four structural proteins: Spike glycoprotein (S), membrane (M), envelope (E) and nucleocapsid (N), and nonstructural proteins, such as Nsp15 protein which is exclusively present on nidoviruses and is absent in other RNA viruses, making it an ideal target in the field of drug design. A virtual screening strategy to search for potential drugs was proposed, using molecular docking to explore a library of approved drugs available in the DrugBank database in order to identify possible NSP15 inhibitors to treat Covid19 disease. We found from the docking analysis that the antiviral drugs: Paritaprevir and Elbasvir, currently both approved for hepatitis C treatment which showed some of the lowest free binding energy values were considered as repositioning drugs to combat SARS-CoV-2. Furthermore, molecular dynamics simulations of the Apo and Holo-Nsp15 systems were performed in order to get insights about the stability of these protein-ligand complexes.


Assuntos
Antivirais/farmacologia , Benzofuranos/farmacologia , Tratamento Farmacológico da COVID-19 , Ciclopropanos/farmacologia , Endorribonucleases/antagonistas & inibidores , Imidazóis/farmacologia , Lactamas Macrocíclicas/farmacologia , Prolina/análogos & derivados , SARS-CoV-2/efeitos dos fármacos , Sulfonamidas/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , COVID-19/virologia , Reposicionamento de Medicamentos , Endorribonucleases/metabolismo , Humanos , Simulação de Acoplamento Molecular , Terapia de Alvo Molecular , Prolina/farmacologia , SARS-CoV-2/metabolismo , Proteínas não Estruturais Virais/metabolismo
5.
Ann Hepatol ; 25: 100337, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33684523

RESUMO

INTRODUCTIONS AND OBJECTIVES: The introduction of direct-acting antiviral (DAA) agents promises to change dramatically the management of hepatitis C in kidney transplant recipients, a patient group where the treatment of hepatitis C is historically challenging. The purpose of the current study was to assess (in a 'real-life' setting) the safety and efficacy of all-oral, interferon-free, direct-acting antiviral agents in kidney transplant recipients with HCV. MATERIAL AND METHODS: We performed a single-arm, multi-center study in a cohort (n = 95) of kidney transplant recipients who underwent antiviral therapy with DAAs. The primary end-point was sustained virologic response (SVR) (serum HCV RNA < 15 IU/mL, 12 weeks after treatment ended; SVR12). We recorded data on on-treatment adverse events (AEs), serious AEs, and laboratory abnormalities. RESULTS: Various regimens were adopted at the discretion of the treating physician: elbasvir/grazoprevir (n = 11), paritaprevir/ritonavir/ombitasvir/dasabuvir (PrOD) regimens ± ribavirin (n = 23), and sofosbuvir-based regimens ± ribavirin (n = 61). The SVR12 rate was 93.7% (89/95) (95% CI, 88%; 98%), according to intention-to-treat analysis; three patients without viral response (n = 3) were found. Ribavirin was administered in 8 (8.4%) allograft recipients. The frequency of drop-outs was 4.2% (4/95) (95% CI, 0.2%; 8.2%); these were related to arthralgia/myalgia (n = 2), fatigue (n = 1), and lowered estimated glomerular filtration rate (eGFR) (n = 1). There were no differences with regard to serum creatinine and eGFR before and after antiviral therapy and during follow-up in the whole cohort. The patient who interrupted antiviral treatment due to raised serum creatinine was on sofosbuvir/daclatasvir regimen; one of the four drop-outs obtained SVR. CONCLUSIONS: All-oral, interferon-free therapy with DAAs for chronic HCV after kidney transplantation was effective and well-tolerated in a 'real-life' clinical setting. Identical results have been observed in patients with intact kidneys or advanced chronic kidney disease. Careful evaluation of kidney function over follow-up in kidney transplant recipients who received DAAs regimens is recommended. Clinical trials aimed to assess whether sustained viral response translates into improved patient/graft survival are under way.


Assuntos
Antivirais/uso terapêutico , Hepatite C/tratamento farmacológico , Transplante de Rim , Resposta Viral Sustentada , 2-Naftilamina/uso terapêutico , Administração Oral , Adulto , Idoso , Anilidas/uso terapêutico , Benzofuranos , Estudos de Coortes , Creatinina/sangue , Ciclopropanos/uso terapêutico , Combinação de Medicamentos , Feminino , Taxa de Filtração Glomerular , Hepatite C/complicações , Hepatite C/patologia , Humanos , Imidazóis , Lactamas Macrocíclicas/uso terapêutico , Masculino , Pessoa de Meia-Idade , Prolina/análogos & derivados , Prolina/uso terapêutico , Quinoxalinas , Ribavirina/uso terapêutico , Ritonavir/uso terapêutico , Sofosbuvir/uso terapêutico , Sulfonamidas/uso terapêutico , Uracila/análogos & derivados , Uracila/uso terapêutico , Valina/uso terapêutico
6.
Acta Trop ; 211: 105595, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32585150

RESUMO

17-N-allylamino-17-demethoxygeldanamycin (17-AAG, tanespimycin) is an inhibitor of heat shock protein 90 (Hsp90), which has been studied in the treatment of cancer such as leukemia or solid tumors. Alternatively, 17-AAG may represent a promising therapeutic agent against leishmaniasis. However, the delivery of 17-AAG is difficult due to its poor aqueous solubility. For exploring the therapeutic value of 17-AAG, we developed solid lipid nanoparticles (SLN) by double emulsion method. SLN exhibited ~100 nm, PDI < 0.2 and zeta potential ~20 mV. In addition, SLN were morphologically spherical with negligible aggregation. The entrapment efficiency of 17-AAG into the lipid matrix reached at nearly 80%. In a separate set of experiments, fluorescent SLN (FITC-labeled) showed a remarkable macrophage uptake, peaking within 2 h of incubation by confocal microscopy. Regarding the drug internalization as critical step for elimination of intracellular Leishmania, this finding demonstrates an important feature of the developed SLN. Collectively, these data indicate the feasibility of developing SLN as potential delivery systems for 17-AAG in leishmaniasis chemotherapy.


Assuntos
Benzoquinonas/metabolismo , Benzoquinonas/farmacologia , Lactamas Macrocíclicas/metabolismo , Lactamas Macrocíclicas/farmacologia , Lipídeos/química , Macrófagos/metabolismo , Nanopartículas/química , Animais , Benzoquinonas/administração & dosagem , Benzoquinonas/química , Portadores de Fármacos/uso terapêutico , Proteínas de Choque Térmico HSP90/uso terapêutico , Lactamas Macrocíclicas/administração & dosagem , Lactamas Macrocíclicas/química , Leishmania , Leishmaniose/tratamento farmacológico , Estrutura Molecular , Solubilidade
7.
Acta Cir Bras ; 35(1): e202000105, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32215465

RESUMO

PURPOSE: To investigate whether heat shock protein 90 (HSP90) is involved in complement regulation in ischemic postconditioning (IPC). METHODS: The left coronary artery of rats underwent 30 min of occlusion, followed by 120 min of reperfusion and treatment with IPC via 3 cycles of 30s reperfusion and 30s occlusion. The rats were injected intraperitoneally with 1 mg/kg HSP90 inhibitor geldanamycin (GA) after anesthesia. Eighty rats were randomly divided into four groups: sham, ischemia-reperfusion (I/R), IPC and IPC + GA. Myocardial infarct size, apoptosis index and the expression of HSP90, C3, C5a, tumor necrosis factor (TNF)-alpha, interleukin (IL)-1ß and c-Jun N-terminal kinase (JNK) were assessed. RESULTS: Compared with the I/R injury, the IPC treatment significantly reduced infarct size, release of troponin T, creatine kinase-MB, and lactate dehydrogenase, and cardiomyocyte apoptosis. These beneficial effects were accompanied by a decrease in TNF-α, IL-1ß, C3, C5a and JNK expression levels. However, all these effects were abrogated by administration of the HSP90 inhibitor GA. CONCLUSION: HSP90 exerts a profound effect on IPC cardioprotection, and may be linked to the inhibition of the complement system and JNK, ultimately attenuating I/R-induced myocardial injury and apoptosis.


Assuntos
Benzoquinonas/farmacologia , Proteínas do Sistema Complemento/metabolismo , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Lactamas Macrocíclicas/farmacologia , Infarto do Miocárdio/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Animais , Creatina Quinase Forma MB/metabolismo , Mediadores da Inflamação , Pós-Condicionamento Isquêmico/métodos , Masculino , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo
8.
Acta cir. bras ; 35(1): e202000105, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1088523

RESUMO

Abstract Purpose To investigate whether heat shock protein 90 (HSP90) is involved in complement regulation in ischemic postconditioning (IPC). Methods The left coronary artery of rats underwent 30 min of occlusion, followed by 120 min of reperfusion and treatment with IPC via 3 cycles of 30s reperfusion and 30s occlusion. The rats were injected intraperitoneally with 1 mg/kg HSP90 inhibitor geldanamycin (GA) after anesthesia. Eighty rats were randomly divided into four groups: sham, ischemia-reperfusion (I/R), IPC and IPC + GA. Myocardial infarct size, apoptosis index and the expression of HSP90, C3, C5a, tumor necrosis factor (TNF)-alpha, interleukin (IL)-1β and c-Jun N-terminal kinase (JNK) were assessed. Results Compared with the I/R injury, the IPC treatment significantly reduced infarct size, release of troponin T, creatine kinase-MB, and lactate dehydrogenase, and cardiomyocyte apoptosis. These beneficial effects were accompanied by a decrease in TNF-α, IL-1β, C3, C5a and JNK expression levels. However, all these effects were abrogated by administration of the HSP90 inhibitor GA. Conclusion HSP90 exerts a profound effect on IPC cardioprotection, and may be linked to the inhibition of the complement system and JNK, ultimately attenuating I/R-induced myocardial injury and apoptosis.


Assuntos
Animais , Ratos , Proteínas do Sistema Complemento/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Benzoquinonas/farmacologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Lactamas Macrocíclicas/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Infarto do Miocárdio/metabolismo , RNA Mensageiro/metabolismo , Distribuição Aleatória , Fator de Necrose Tumoral alfa/metabolismo , Ratos Sprague-Dawley , Mediadores da Inflamação , Creatina Quinase Forma MB/metabolismo , Pós-Condicionamento Isquêmico/métodos
9.
Sci Rep ; 9(1): 14756, 2019 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-31611575

RESUMO

Leishmaniasis is a neglected disease that affects millions of individuals around the world. Regardless of clinical form, treatment is based primarily on the use of pentavalent antimonials. However, such treatments are prolonged and present intense side effects, which lead to patient abandonment in many cases. The search for chemotherapeutic alternatives has become a priority. Heat Shock Protein 90 (Hsp90) inhibitors have recently come under investigation due to antiparasitic activity in Plasmodium sp., Trypanosoma sp. and Leishmania sp. Some of these inhibitors, such as geldanamycin and its analogs, 17-AAG and 17-DMAG, bind directly to Hsp90, thereby inhibiting its activity. Previous studies have demonstrated that different parasite species are more susceptible to some of these inhibitors than host cells. We hypothesized that this increased susceptibility may be due to differences in binding of Hsp90 inhibitors to Leishmania protein compared to host protein. Based on the results of the in silico approach used in the present study, we propose that geldanamycin, 17-AAG and 17-DMAG present an increased tendency to bind to the N-terminal domain of Leishmania amazonensis Hsp83 in comparison to human Hsp90. This could be partially explained by differences in intermolecular interactions between each of these inhibitors and Hsp83 or Hsp90. The present findings demonstrate potential for the use of these inhibitors in the context of anti-Leishmania therapy.


Assuntos
Benzoquinonas/farmacologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Lactamas Macrocíclicas/farmacologia , Leishmania/efeitos dos fármacos , Proteínas de Protozoários/antagonistas & inibidores , Tripanossomicidas/farmacologia , Benzoquinonas/química , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Lactamas Macrocíclicas/química , Leishmania/metabolismo , Leishmaniose/tratamento farmacológico , Leishmaniose/parasitologia , Simulação de Acoplamento Molecular , Proteínas de Protozoários/metabolismo , Tripanossomicidas/química
10.
PLoS One ; 14(7): e0220393, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31361762

RESUMO

The wild type huntingtin protein (Htt), supports the production of brain-derived neurotrophic factor (BDNF), a survival factor for striatal neurons, through cytoplasmic sequestering of RE-1silencing transcription factor (REST). In Huntington´s Disease an inherited degenerative disease, caused by a CAG expansion in the 5´coding region of the gene, the mutant huntingtin protein (mHtt), causes that REST enters pathologically into the nucleus of cells, resulting in the repression of neuronal genes including BDNF, resulting in the progressive neuronal death. It has been reported that Htt associates with Hsp90 and this interaction is involved in regulation of huntingtin aggregation. Discovering mechanisms to reduce the cellular levels of mutant huntingtin and REST provide promising strategies for treating Huntington disease. Here, we use the yeast two-hybrid system to show that N-terminus or REST interacts with the heat shock protein 90 (Hsp90) and identifies REST as an Hsp90 Client Protein. To assess the effects of Hsp90 we used antisense oligonucleotide, and evaluated the levels mHtt and REST levels. Our results show that direct knockdown of endogenous Hsp90 significantly reduces the levels of REST and mutant Huntingtin, decreased the percentage of cells with mHtt in nucleus and rescued cells from mHtt-induced cellular cytotoxicity. Additionally Hsp90-specific inhibitors geldanamicyn and PUH71 dramatically reduced mHtt and REST levels, thereby providing neuroprotective activity. Our data show that Hsp90 is necessary to maintain the levels of REST and mHtt, which suggests that the interactions between Hsp90-REST and Hsp90-Huntingtin could be potential therapeutic targets in Huntington's disease.


Assuntos
Proteínas de Choque Térmico HSP90/metabolismo , Proteína Huntingtina/metabolismo , Doença de Huntington/metabolismo , Proteínas Repressoras/química , Proteínas Repressoras/metabolismo , Benzoquinonas/farmacologia , Sítios de Ligação , Linhagem Celular , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Técnicas de Silenciamento de Genes , Proteínas de Choque Térmico HSP90/genética , Humanos , Proteína Huntingtina/genética , Doença de Huntington/genética , Lactamas Macrocíclicas/farmacologia , Modelos Biológicos , Mutação , Ligação Proteica/efeitos dos fármacos
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