Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 20
Filtrar
1.
Nano Lett ; 24(33): 10186-10195, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39136297

RESUMO

Despite its significant clinical efficacy as a first-line treatment for advanced bladder cancer, cisplatin-based chemotherapy provides a limited benefit for patients with lymphovascular invasion (LVI), which is characterized by the presence of tumor emboli within blood vessels and associated with enhanced cisplatin resistance and metastatic potential. Notably, platelets, a critical component of LVI, hinder the delivery of chemotherapeutic agents to tumors and facilitate metastasis. Consequently, platelet function inhibition holds the potential to disrupt LVI formation, as well as augment the antitumor activity of cisplatin. Herein, we developed a tumor microenvironment-targeted nanodrug with lipid-coated mesoporous silica nanoparticles (silicasomes) that synergistically combines cisplatin with an antiplatelet agent, tirofiban, for bladder cancer treatment. The customized nanodrug can concurrently prevent LVI formation and enhance the chemotherapeutic efficacy without significant adverse effects. This study supports the integration of chemotherapy and antiplatelet therapy via a silicasome-based nanosystem as a highly promising strategy for bladder cancer management.


Assuntos
Cisplatino , Nanopartículas , Dióxido de Silício , Neoplasias da Bexiga Urinária , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/patologia , Humanos , Dióxido de Silício/química , Cisplatino/farmacologia , Cisplatino/química , Cisplatino/uso terapêutico , Nanopartículas/química , Linhagem Celular Tumoral , Animais , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Microambiente Tumoral/efeitos dos fármacos , Camundongos , Invasividade Neoplásica/prevenção & controle , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/uso terapêutico , Oligopeptídeos
2.
BMJ Open Ophthalmol ; 9(1)2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39134323

RESUMO

AIMS: This study aimed to evaluate the effectiveness of somatostatin analogues (SA) for cystoid maculopathy (CM) in retinitis pigmentosa (RP) patients. MATERIALS AND METHODS: In this retrospective case series, clinical and imaging characteristics of 28 RP patients with CM, unresponsive to carbonic anhydrase inhibitors, were collected from medical charts. All patients received SA treatment as an alternative (octreotide long-acting release at 20 mg/month or 30 mg/month, or lanreotide at 90 mg/month or 120 mg/month). Outcome measures were mean reduction in foveal thickness (FT) and foveal volume (FV) and mean increase in best-corrected visual acuity at 3, 6 and 12 months of treatment initiation. Linear mixed models were used to calculate the effectiveness over time. RESULTS: 52 eyes of 28 RP patients were included; 39% were male. The median age at the start of treatment was 39 years (IQR 30-53). Median follow-up was 12 months (range 6-12). From baseline to 12 months, the mean FT decreased from 409±136 µm to 334±119 µm and the mean FV decreased from 0.31±0.10 mm3 to 0.25±0.04 mm3. Linear mixed model analyses showed a significant decrease in log FT and log FV at 3, 6 and 12 months after the start of treatment compared with baseline measurements (p<0.001, p<0.001, p<0.001). Mean best-corrected visual acuity did not increase significantly (0.46±0.35 logMAR to 0.45±0.38 logMAR after 12 months). DISCUSSION: SA may be an effective alternative treatment to reduce CM in RP patients.


Assuntos
Retinose Pigmentar , Somatostatina , Tomografia de Coerência Óptica , Acuidade Visual , Humanos , Retinose Pigmentar/tratamento farmacológico , Masculino , Feminino , Somatostatina/análogos & derivados , Somatostatina/uso terapêutico , Estudos Retrospectivos , Pessoa de Meia-Idade , Acuidade Visual/efeitos dos fármacos , Adulto , Peptídeos Cíclicos/uso terapêutico , Octreotida/uso terapêutico , Octreotida/administração & dosagem , Resultado do Tratamento , Edema Macular/tratamento farmacológico , Edema Macular/etiologia
3.
Int Immunopharmacol ; 139: 112602, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39033660

RESUMO

Chronic pain has emerged as a significant public health issue, seriously affecting patients' quality of life and psychological well-being, with a lack of effective pharmacological treatments. Numerous studies have indicated that macrophages play a crucial role in inflammatory pain, and targeting neuro-immune interactions for drug development may represent a promising direction for pain management. Chilobrachys jingzhao (C. jingzhao) is used as a folk medicine of the Li nationality with the efficacy of eliminating swelling, detoxicating, and relieving pain, and the related products are widely used in the market. However, the chemical constituents of C. jingzhao have not been reported, and the pharmacodynamic substance and the precise functional mechanism are unrevealed. Here we isolated a cyclic dipeptide, cyclo(L-Pro-L-Trp) (CPT) from C. jingzhao for the first time. CPT remarkably alleviated formalin-induced inflammatory pain and significantly inhibited inflammatory responses. In vivo, CPT attenuated neutrophil infiltration and plantar tissue edema and suppressed the mRNA expression of pro-inflammatory molecules. In vitro, CPT suppressed inflammation triggered by lipopolysaccharide (LPS) in both RAW 264.7 and iBMDM cells, reducing expressions of inducible nitric oxide synthase (iNOS), superoxide, and pro-inflammatory molecules. A mechanistic study revealed that CPT exerted an anti-inflammatory activity by blocking the mitogen-activated protein kinases (MAPK) and nuclear factor-kappa B (NF-κB) signaling pathways, as well as alleviating the ubiquitination of tumor necrosis factor receptor-associated factor 6 (TRAF6). Our results elucidated the pharmacodynamic material basis of C. jingzhao, and CPT can be a promising lead for alleviating inflammation and inflammatory pain.


Assuntos
Anti-Inflamatórios , Formaldeído , Inflamação , NF-kappa B , Transdução de Sinais , Fator 6 Associado a Receptor de TNF , Animais , NF-kappa B/metabolismo , Camundongos , Fator 6 Associado a Receptor de TNF/metabolismo , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios/farmacologia , Masculino , Transdução de Sinais/efeitos dos fármacos , Inflamação/tratamento farmacológico , Células RAW 264.7 , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/uso terapêutico , Dor/tratamento farmacológico , Dor/induzido quimicamente , Analgésicos/uso terapêutico , Analgésicos/farmacologia , Humanos , Edema/tratamento farmacológico , Edema/induzido quimicamente , Edema/imunologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia
4.
J Med Chem ; 67(14): 12085-12098, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38991128

RESUMO

Liver fibrosis is a condition characterized by aberrant proliferation of connective tissue in the liver resulting from diverse etiological factors. G protein-coupled receptor GPR55 has recently been identified as a regulator of liver diseases. Herein, we report the discovery of a cyclic peptide P1-1 that antagonizes GPR55 and suppresses collagen secretion in hepatic stellate cells. The alanine scanning and docking study was carried out to predict the binding mode and allowed for further structural optimization of peptide antagonists for GPR55. The subsequent in vivo study demonstrated that P1-1 ameliorates CCl4-induce and MCD-diet-induce acute liver inflammation and fibrosis. Further study indicates that P1-1 reduces reactive oxygen species (ROS) production, attenuates ER stress, and inhibits mitochondria-associated hepatocyte apoptosis. In this work, we provided the first successful example of antagonizing GPR55 for liver inflammation and fibrosis, which validates GPR55 as a promising target for the treatment of liver fibrosis and affords a high-potent GPR55 antagonist P1-1 as a potential therapeutic candidate.


Assuntos
Cirrose Hepática , Receptores de Canabinoides , Receptores Acoplados a Proteínas G , Animais , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/patologia , Cirrose Hepática/metabolismo , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores Acoplados a Proteínas G/metabolismo , Humanos , Receptores de Canabinoides/metabolismo , Camundongos , Masculino , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Simulação de Acoplamento Molecular , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio/metabolismo , Apoptose/efeitos dos fármacos , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/química , Peptídeos Cíclicos/síntese química , Peptídeos Cíclicos/uso terapêutico , Descoberta de Drogas , Relação Estrutura-Atividade , Estresse do Retículo Endoplasmático/efeitos dos fármacos
5.
Pharmacol Res ; 206: 107252, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38945380

RESUMO

Adagrasib (MRTX849), an approved and promising KRAS G12C inhibitor, has shown the promising results for treating patients with advanced non-small cell lung cancer (NSCLC) or colorectal cancer (CRC) harboring KRAS-activating mutations. However, emergence of the acquired resistance limits its long-term efficacy and clinical application. Further understanding of the mechanism of the acquired resistance is crucial for developing more new effective therapeutic strategies. Herein, we firstly found a new connection between the acquired resistance to MRTX849 and nuclear factor erythroid 2-related factor 2 (Nrf2). The expression levels of Nrf2 and GLS1 proteins were substantially elevated in different CRC cell lines with the acquired resistance to MRTX849 in comparison with their corresponding parental cell lines. Next, we discovered that RA-V, one of natural cyclopeptides isolated from the roots of Rubia yunnanensis, could restore the response of resistant CRC cells to MRTX849. The results of molecular mechanisms showed that RA-V suppressed Nrf2 protein through the ubiquitin-proteasome-dependent degradation, leading to the induction of oxidative and ER stress, and DNA damage in CRC cell lines. Consequently, RA-V reverses the resistance to MRTX849 by inhibiting the Nrf2/GLS1 axis, which shows the potential for further developing into one of novel adjuvant therapies of MRTX849.


Assuntos
Neoplasias Colorretais , Fator 2 Relacionado a NF-E2 , Peptídeos Cíclicos , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/genética , Humanos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Neoplasias Colorretais/genética , Linhagem Celular Tumoral , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Animais , Antineoplásicos Fitogênicos/farmacologia , Camundongos Nus
6.
Endocr Relat Cancer ; 31(9)2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38913539

RESUMO

Prospective data are lacking on early somatostatin analog (SSA) therapy in bronchopulmonary neuroendocrine tumors (BP-NETs; typical carcinoids and atypical carcinoids (TCs and ACs)). SPINET (EudraCT: 2015-004992-62; NCT02683941) was a phase III, double-blind study of lanreotide autogel/depot (LAN; 120 mg every 28 days) plus best supportive care (BSC) vs placebo plus BSC, with an optional open-label treatment phase (LAN plus BSC). Patients had metastatic/unresectable, somatostatin receptor (SSTR)-positive TCs or ACs. Recruitment was stopped early owing to slow accrual; eligible patients from the double-blind phase transitioned to open-label LAN. The adapted primary endpoint was progression-free survival (PFS) during either phase for patients receiving LAN. Seventy-seven patients were randomized (LAN, n = 51 (TCs, n = 29; ACs, n = 22); placebo, n = 26 (TCs, n = 16; ACs, n = 10)). Median (95% CI) PFS during double-blind and open-label phases in patients receiving LAN was 16.6 (11.3; 21.9) months overall (primary endpoint), 21.9 (12.8, not calculable (NC)) months in TCs, and 13.8 (5.4; 16.6) months in ACs. During double-blind treatment, median (95% CI) PFS was 16.6 (11.3; 21.9) months for LAN vs 13.6 (8.3; NC) months for placebo (not significant); corresponding values were 21.9 (13.8; NC) and 13.9 (13.4; NC) months, respectively, in TCs and 13.8 (5.4; 16.6) and 11.0 (2.8; 16.9) months, respectively, in ACs. Patients' quality of life did not deteriorate and LAN was well tolerated. Although recruitment stopped early and the predefined sample size was not met, SPINET is the largest prospective study to date of SSA therapy in SSTR-positive TCs and ACs and suggests clinical benefit in TCs.


Assuntos
Tumores Neuroendócrinos , Peptídeos Cíclicos , Somatostatina , Humanos , Somatostatina/análogos & derivados , Somatostatina/uso terapêutico , Somatostatina/administração & dosagem , Peptídeos Cíclicos/administração & dosagem , Peptídeos Cíclicos/uso terapêutico , Feminino , Masculino , Pessoa de Meia-Idade , Método Duplo-Cego , Idoso , Tumores Neuroendócrinos/tratamento farmacológico , Adulto , Antineoplásicos/uso terapêutico , Antineoplásicos/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Idoso de 80 Anos ou mais
7.
Infect Dis (Lond) ; 56(7): 575-580, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38743059

RESUMO

OBJECTIVE: To study the effect of plitidepsin antiviral treatment in immunocompromised COVID-19 patients with underlying haematological malignancies or solid tumours, particularly those who have undergone anti-CD20 therapies. DESIGN: We conducted a retrospective observational study, involving 54 adults treated with plitidepsin on compassionate use as an antiviral drug. Our analysis compared outcomes between patients with solid tumours and those with haematological malignancies, and a cohort of cases treated or not with anti-CD20 monoclonal antibodies. RESULTS: Patients with a history of anti-CD20 therapies showed a prolonged time-to-negative RT-PCR for SARS-CoV-2 infection compared to non-treated patients (33 d (28;75) vs 15 (11;25); p = .002). Similar results were observed in patients with solid tumours in comparison to those with haematological malignancies (13 (10;16) vs 26 (17;50); p < .001). No serious adverse events were documented. CONCLUSIONS: Patients with haematological malignancies appear to be at a heightened risk for delayed SARS-CoV-2 clearance and subsequent clinical complications. These findings support plitidepsin as a well-tolerated treatment in this high-risk group. A phase II clinical trial (NCT05705167) is ongoing to evaluate plitidepsin as an antiviral drug in this population.KEY POINTSHaematological patients face an increased risk for severe COVID-19.Anti-CD20 therapies could increase fatal outcomes in COVID-19 patients.Persistent viral replication is increased in immunocompromised patients.Plitidepsin does not lead to new serious adverse events in immunocompromised patients.


Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19 , Depsipeptídeos , Neoplasias Hematológicas , Neoplasias , Peptídeos Cíclicos , SARS-CoV-2 , Humanos , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/complicações , Idoso , Depsipeptídeos/uso terapêutico , Depsipeptídeos/efeitos adversos , Neoplasias/tratamento farmacológico , Neoplasias/complicações , Peptídeos Cíclicos/uso terapêutico , Antivirais/uso terapêutico , Resultado do Tratamento , Adulto , Ensaios de Uso Compassivo , Hospedeiro Imunocomprometido , Antígenos CD20/imunologia , Idoso de 80 Anos ou mais
8.
J Med Chem ; 67(6): 4889-4903, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38485922

RESUMO

Directly blocking the Keap1-Nrf2 pathway is a promising strategy for the mitigation of acute lung injury (ALI). Peptide Keap1-Nrf2 inhibitors have been reported to have a high Keap1 binding affinity. However, these inhibitors showed weak activity in cells and/or animals. In this study, we designed a series of linear peptides from an Nrf2-based 9-mer Ac-LDEETGEFL-NH2. To improve the cellular activity, we further designed cyclic peptides based on the crystal complex of Keap1 with a linear peptide. Among them, cyclic 9-mer ZC9 targeting Keap1 showed a better affinity (KD2 = 51 nM). Specifically, it exhibited an acceptable water solubility (>38 mg/mL), better cell permeability, cell activity, and metabolic stability (serum t1/2 > 24 h). In the in vitro LPS-induced oxidative damages and ALI model, ZC9 showed significant dose-response reversal activity without apparent toxicity. In conclusion, our results suggested ZC9 as a lead cyclic peptide targeting the Keap1-Nrf2 pathway for ALI clinical treatment.


Assuntos
Lesão Pulmonar Aguda , Peptídeos Cíclicos , Animais , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/uso terapêutico , Peptídeos Cíclicos/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Peptídeos/química , Lesão Pulmonar Aguda/tratamento farmacológico
9.
Trends Mol Med ; 30(5): 420-422, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38453528

RESUMO

In a recent report, Zampaloni et al. describe a novel tethered macrocyclic peptide (MCP) antibiotic, zosurabalpin, that disrupts the essential function of the LptB2FGC complex in Gram-negative bacteria and demonstrates efficacy against carbapenem-resistant Acinetobacter baumannii (CRAB). Its preclinical success suggests a substantial shift in treating antibiotic resistance, pending clinical trials to validate its effectiveness, pharmacokinetics, and resistance management.


Assuntos
Antibacterianos , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Acinetobacter baumannii/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Peptídeos Cíclicos/uso terapêutico , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/química , Animais
10.
Bioorg Chem ; 145: 107203, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38377817

RESUMO

Antimicrobial photodynamic therapy (PDT) is a promising alternative to antibiotics for eradicating pathogenic bacterial infections. It holds advantage of not inducing antimicrobial resistance but is limited for the treatment of gram-negative bacterial infection due to the lack of photosensitizer (PS) capable of targeted permeating the outer membrane (OM) of gram-negative bacteria. To facilitate the targeted permeability of PS, cyclic polymyxin b nonapeptide that can specifically bind to the lipopolysaccharide on OM, is conjugated to an FDA approved PS chlorin e6 via variable linkers. Based on structure to activity study, C6pCe6 with aminohexanoic linker and P2pCe6 with amino-3, 6-dioxaoctanoic linker are identified to preferentially image gram-negative bacteria. These two conjugates also exhibit improved aqueous dispersity and enhanced ROS generation, consequently enabled their selective bactericidal activities against gram-negative bacteria upon 660 nm light irradiation. The effective photobactericidal ability of P2pCe6 is further validated on P. aeruginosa infected G. mellonella. Moreover, it is demonstrated to effectively treat the P. aeruginosa infection and accelerate the healing process at the wound site of mouse. Owing to the light irradiation triggered targeted imaging and enhanced bactericidal capacities, P2pCe6 hold great potential to serve as a potent PS for mediating the phototheranostics of gram-negative bacterial infection.


Assuntos
Anti-Infecciosos , Infecções por Bactérias Gram-Negativas , Fotoquimioterapia , Animais , Camundongos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Fármacos Fotossensibilizantes/química , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/uso terapêutico , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Fotoquimioterapia/métodos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antibacterianos/química , Anti-Infecciosos/farmacologia , Bactérias Gram-Negativas
11.
Oncologist ; 29(5): e643-e654, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38206830

RESUMO

BACKGROUND: In advanced neuroendocrine tumors (NET), antiproliferative treatment options beyond somatostatin analogs remain limited. Temozolomide (TMZ) has shown efficacy in NET alone or combined with other drugs. MATERIALS AND METHODS: SONNET (NCT02231762) was an open, multicenter, prospective, phase II study to evaluate lanreotide autogel 120 mg (LAN) plus TMZ in patients with progressive advanced/metastatic grade 1/2 gastroenteropancreatic (GEP) NET or of unknown primary. Patients could be enrolled at first-line or higher therapy line. The primary endpoint was disease control rate ([DCR], rate of stable disease [SD], partial [PR], and complete response [CR]) at 6 months of LAN and TMZ. Patients with nonfunctioning (NF) NET without progression at 6 months were randomized to 6-month LAN maintenance or watch and wait, patients with functioning (F)-NET with clinical benefit (PR, SD) continued on LAN. RESULTS: Fifty-seven patients were recruited. The majority of patients received the study drug at second or higher treatment line and had an NET G2. DCR at 6 months LAN and TMZ was 73.5%. After 6 months of further LAN maintenance, 54.5% of patients with F-NET and 71.4% with NF-NET had SD or PR vs 41.7% with NF-NET on observation only. LAN and TMZ were effective in all subgroups analyzed. At 12 months of follow-up, median progression-free survival was 11.1 months. Median serum chromogranin A decreased except in NF-NET on observation. O6-methylguanine DNA methyltransferase promoter methylation appeared to better reflect TMZ response than loss of gene expression. During combination therapy, the most frequent treatment-emergent adverse events grade 3/4 reported were nausea (14%), thrombocytopenia (12.3%), and neutropenia (8.8%). Four deaths were reported resulting from severe adverse events not considered related to study medication. CONCLUSIONS: LAN plus TMZ is a treatment option for patients with progressive GEP-NET with more aggressive biological profile showing a manageable safety profile.


Assuntos
Neoplasias Intestinais , Tumores Neuroendócrinos , Neoplasias Pancreáticas , Peptídeos Cíclicos , Somatostatina , Somatostatina/análogos & derivados , Temozolomida , Humanos , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Temozolomida/administração & dosagem , Somatostatina/uso terapêutico , Somatostatina/farmacologia , Somatostatina/administração & dosagem , Tumores Neuroendócrinos/tratamento farmacológico , Tumores Neuroendócrinos/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Idoso , Peptídeos Cíclicos/uso terapêutico , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/administração & dosagem , Neoplasias Intestinais/tratamento farmacológico , Neoplasias Intestinais/patologia , Adulto , Estudos Prospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Idoso de 80 Anos ou mais
12.
Chem Commun (Camb) ; 60(6): 632-645, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38131333

RESUMO

Existing therapies for neurodegenerative diseases like Parkinson's and Alzheimer's address only their symptoms and do not prevent disease onset. Common therapeutic agents, such as small molecules and antibodies struggle with insufficient selectivity, stability and bioavailability, leading to poor performance in clinical trials. Peptide-based therapeutics are emerging as promising candidates, with successful applications for cardiovascular diseases and cancers due to their high bioavailability, good efficacy and specificity. In particular, cyclic peptides have a long in vivo stability, while maintaining a robust antibody-like binding affinity. However, the de novo design of cyclic peptides is challenging due to the lack of long-lived druggable pockets of the target polypeptide, absence of exhaustive conformational distributions of the target and/or the binder, unknown binding site, methodological limitations, associated constraints (failed trials, time, money) and the vast combinatorial sequence space. Hence, efficient alignment and cooperation between disciplines, and synergies between experiments and simulations complemented by popular techniques like machine-learning can significantly speed up the therapeutic cyclic-peptide development for neurodegenerative diseases. We review the latest advancements in cyclic peptide design against amyloidogenic targets from a computational perspective in light of recent advancements and potential of machine learning to optimize the design process. We discuss the difficulties encountered when designing novel peptide-based inhibitors and we propose new strategies incorporating experiments, simulations and machine learning to design cyclic peptides to inhibit the toxic propagation of amyloidogenic polypeptides. Importantly, these strategies extend beyond the mere design of cyclic peptides and serve as template for the de novo generation of (bio)materials with programmable properties.


Assuntos
Doenças Neurodegenerativas , Peptídeos Cíclicos , Humanos , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/uso terapêutico , Peptídeos Cíclicos/química , Peptídeos/química , Aprendizado de Máquina , Doenças Neurodegenerativas/tratamento farmacológico
13.
Mar Drugs ; 21(12)2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-38132930

RESUMO

Parasitic diseases still compromise human health. Some of the currently available therapeutic drugs have limitations considering their adverse effects, questionable efficacy, and long treatment, which have encouraged drug resistance. There is an urgent need to find new, safe, effective, and affordable antiparasitic drugs. Marine-derived cyclic peptides have been increasingly screened as candidates for developing new drugs. Therefore, in this review, a systematic analysis of the scientific literature was performed and 25 marine-derived cyclic peptides with antiparasitic activity (1-25) were found. Antimalarial activity is the most reported (51%), followed by antileishmanial (27%) and antitrypanosomal (20%) activities. Some compounds showed promising antiparasitic activity at the nM scale, being active against various parasites. The mechanisms of action and targets for some of the compounds have been investigated, revealing different strategies against parasites.


Assuntos
Antiprotozoários , Leishmaniose , Doenças Parasitárias , Humanos , Antiparasitários/química , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/uso terapêutico , Leishmaniose/tratamento farmacológico , Antiprotozoários/química , Doenças Parasitárias/tratamento farmacológico
14.
Braz. j. med. biol. res ; 49(9): e5287, 2016. graf
Artigo em Inglês | LILACS | ID: lil-788941

RESUMO

Inflammation plays a pivotal role in ischemic stroke, when activated microglia release excessive pro-inflammatory mediators. The inhibition of integrin αvβ3 improves outcomes in rat focal cerebral ischemia models. However, the mechanisms by which microglia are neuroprotective remain unclear. This study evaluated whether post-ischemic treatment with another integrin αvβ3 inhibitor, the cyclic arginine-glycine-aspartic acid (RGD) peptide-cGRGDdvc (LXW7), alleviates cerebral ischemic injury. The anti-inflammatory effect of LXW7 in activated microglia within rat focal cerebral ischemia models was examined. A total of 108 Sprague-Dawley rats (250–280 g) were subjected to middle cerebral artery occlusion (MCAO). After 2 h, the rats were given an intravenous injection of LXW7 (100 μg/kg) or phosphate-buffered saline (PBS). Neurological scores, infarct volumes, brain water content (BWC) and histology alterations were determined. The expressions of pro-inflammatory cytokines [tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β)], and Iba1-positive activated microglia, within peri-ischemic brain tissue, were assessed with ELISA, western blot and immunofluorescence staining. Infarct volumes and BWC were significantly lower in LXW7-treated rats compared to those in the MCAO + PBS (control) group. The LXW7 treatment lowered the expression of pro-inflammatory cytokines. There was a reduction of Iba1-positive activated microglia, and the TNF-α and IL-1β expressions were attenuated. However, there was no difference in the Zea Longa scores between the ischemia and LXW7 groups. The results suggest that LXW7 protected against focal cerebral ischemia and attenuated inflammation in activated microglia. LXW7 may be neuroprotective during acute MCAO-induced brain damage and microglia-related neurodegenerative diseases.


Assuntos
Animais , Masculino , Ratos , Anti-Inflamatórios/uso terapêutico , Isquemia Encefálica/tratamento farmacológico , Infarto da Artéria Cerebral Média/complicações , Inflamação/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Peptídeos Cíclicos/uso terapêutico , Isquemia Encefálica/etiologia , Modelos Animais de Doenças , Interleucina-1beta/metabolismo , Microglia/efeitos dos fármacos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo
15.
Arq. bras. endocrinol. metab ; 54(5): 502-506, 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-554213

RESUMO

Thyrotropin (TSH) secreting pituitary adenomas (TSH-omas) account for < 1 percent of all pituitary adenomas and are a rare cause of hyperthyroidism. The diagnosis is often made at the stage of macroadenoma because of the aggressive nature of the tumor and due to the fact that patients are mistakenly treated for more common primary hyperthyroidism for a long time. First line therapy is transsphenoidal resection of the tumor, which can cure one-third of the patients completely. However, if surgery is not possible or curative, pituitary radiotherapy and/or somatostatin analogs (SSA) can be useful. We report the case of a 54-year-old woman treated 20 years earlier for a mistakenly suspected primary hyperthyroidism. Given the persistence of symptoms she was studied further and was diagnosed with a thyrotropinoma. Despite the delay in diagnosis and prior thyroid ablation, a microadenoma was found. As transsphenoidal surgery was not considered effective, medical therapy with a somatostatin analogue was initiated. Currently, at four years of follow-up, the patient continues on this treatment and remains euthyroid and asymptomatic. We report a case of successful long-term treatment with SSA, after unsuccessful surgery.


Tirotrofinomas (TSH-omas) representam < 1 por cento dos adenomas hipofisários. Eles são uma causa muito rara de hipertireoidismo. O diagnóstico é frequentemente feito na fase de macroadenoma em consequência da natureza agressiva do tumor e do feito de que os doentes são tratados inicialmente por engano e por um longo tempo para hipertireoidismo primário. A terapêutica de primeira linha é a ressecção transesfenoidal do tumor, que cura um terço dos pacientes completamente. Contudo, se a cirurgia não for possível ou curativa, a radioterapia da pituitária e/ou o tratamento com análogos da somatostatina (SSA) podem ser úteis. Relatou-se o caso de uma mulher de 54 anos, tratada há 20 anos por uma suspeita equivocada de hipertireoidismo primário. Dada a persistência dos sintomas, foram realizados mais exames e a paciente foi diagnosticada com TSH-oma. Apesar do diagnóstico tardio e da ablação prévia com iodo radioativo, encontrou-se um microadenoma. Como a cirurgia transesfenoidal não foi considerada eficaz, iniciou-se o tratamento da paciente com SSA. Atualmente, após quatro anos de acompanhamento, a paciente continua com o tratamento e permanece eutireoidea e assintomática. Neste artigo, relatou-se a eficácia da terapia medicamentosa com SSA em longo prazo, após cirurgia não eficaz.


Assuntos
Feminino , Humanos , Pessoa de Meia-Idade , Adenoma/tratamento farmacológico , Antineoplásicos Hormonais/uso terapêutico , Peptídeos Cíclicos/uso terapêutico , Neoplasias Hipofisárias/tratamento farmacológico , Somatostatina/análogos & derivados , Tireotropina , Adenoma , Assistência de Longa Duração , Neoplasias Hipofisárias , Somatostatina/uso terapêutico
16.
Arq. bras. endocrinol. metab ; 52(9): 1452-1460, Dec. 2008. tab, ilus
Artigo em Inglês | LILACS | ID: lil-504550

RESUMO

This study aims to compare economic and patient impacts of the treatment of acromegaly with two different somatostatin analogues (octreotide LAR and lanreotide SR) in Brazil. A cost-effectiveness analysis was carried out under the Brazilian Public Health Care System (SUS) perspective. A decision analytical model was developed based on the Brazilian Public Health Care System Clinical Guideline for Acromegaly. A hypothetical cohort of 276 patients was followed for two years. Data were extracted from literature and administrative databases. Based on the analytical model, treatment with octreotide LAR would avoid 12 and 17 cases of GH and IGF-I elevated serum levels, respectively. Octreotide LAR was a cost-saving strategy, with net savings of R$10,448,324 (US$4,465,096) to SUS. Annual net savings per patient were R$ 18,928 (US$8,089). Treatment of acromegaly with octreotide LAR is a dominant strategy when compared to the treatment with lanreotide SR in Brazil. Sensitivity analysis did not alter the cost-saving status.


O objetivo deste estudo é comparar o impacto econômico e o impacto nos pacientes com acromegalia do tratamento com dois diferentes análogos de somatostatina (octreotida LAR e lanreotide SR) no Brasil. Um estudo de custoefetividade foi realizado a partir da perspectiva do Sistema Único de Saúde (SUS). Foi desenvolvido um modelo analítico de decisão baseado no Protocolo Clínico e Diretrizes Terapêuticas de Acromegalia do SUS. Uma coorte hipotética de 276 pacientes foi seguida por dois anos. Dados foram obtidos da literatura e bases de dados oficiais do SUS. Baseado no modelo analítico, o tratamento com octreotida LAR evitaria 12 e 17 casos com níveis elevados de GH e IGF-I, respectivamente. Octreotida LAR foi uma estratégia econômica, gerando economia de R$10.448.324 (US$4.465.096) para o SUS. A economia anual por paciente foi de R$18.928 (US$8.089). O tratamento de acromegalia com octreotida LAR é estratégia dominante quando comparado com o tratamento com lanreotida SR no Brasil. A análise de sensibilidade não alterou seu status de econômica.


Assuntos
Humanos , Acromegalia/tratamento farmacológico , Antineoplásicos Hormonais/economia , Atenção à Saúde/economia , Octreotida/economia , Peptídeos Cíclicos/economia , Somatostatina/análogos & derivados , Acromegalia/economia , Antineoplásicos Hormonais/uso terapêutico , Brasil , Análise Custo-Benefício , Octreotida/uso terapêutico , Guias de Prática Clínica como Assunto , Peptídeos Cíclicos/uso terapêutico , Sensibilidade e Especificidade , Somatostatina/economia , Somatostatina/uso terapêutico
17.
Gac. méd. Méx ; 142(6): 511-514, nov.-dic. 2006. ilus
Artigo em Espanhol | LILACS | ID: lil-568940

RESUMO

La mucormicosis es una infección causada por hongos de la clase Zygomycetes. Existen varias formas de presentación clínica, siendo las más comunes la rinocerebral y la pulmonar. La mucormicosis renal aislada es un tipo de mucormicosis muy poco frecuente hasta el momento; se han reportado 25 casos en la literatura. Se presenta el caso de una paciente con leucemia aguda que desarrolló mucormicosis renal aislada, y se revisa la literatura.


Mucormycosis is an infection caused by a class Zygomycetes fungi. The rhinocerebral and pulmonary are the most common clinical presentations. Renal mucormycosis is a very rare form. To date, only 25 cases have been reported in the literature. We describe the case of a patient with leukemia who developed isolated renal mucormycosis and review the literature.


Assuntos
Humanos , Feminino , Adulto , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Mucormicose/complicações , Nefropatias/complicações , Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Equinocandinas , Leucemia-Linfoma Linfoblástico de Células Precursoras/microbiologia , Mucormicose/diagnóstico , Mucormicose/terapia , Nefrectomia , Nefropatias/microbiologia , Nefropatias/cirurgia , Peptídeos Cíclicos/uso terapêutico , Rim/microbiologia , Rim/patologia , Rim/cirurgia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
18.
J. bras. pneumol ; 32(5): 449-460, set.-out. 2006. ilus
Artigo em Português | LILACS | ID: lil-452403

RESUMO

Aborda-se sumariamente o espectro de ação, aspectos farmacológicos e toxicológicos e eficácia clínica de anfotericina B lipossomal, anfotericina B em dispersão coloidal, complexo lipídico de anfotericina B, voriconazol e caspofungina. Discute-se o uso desses antifúngicos mais recentes considerando a segurança, a eficiência e o custo da terapia. Sugestões para o uso clínico dessas drogas em infecções pulmonares e sistêmicas são apresentadas, destacando-se a menor toxicidade das formulações lipídicas da anfotericina B em relação à medicação convencional, a possibilidade de terapia primária da aspergilose invasiva, scedosporiose e fusariose com voriconazol e a caspofungina como opção terapêutica na candidíase disseminada e na aspergilose invasiva.


We summarize here data regarding the spectrum of action, the pharmacological aspects, the toxicological aspects and the clinical efficacy of liposomal amphotericin B, amphotericin B in colloidal dispersion, amphotericin B lipid complex, voriconazole and caspofungin. We discuss the use of these more recently introduced antifungal agents in terms of their safety, efficiency and cost. We also offer suggestions for the clinical use of these drugs in pulmonary and systemic infections, with an emphasis on the lower toxicity of the lipid formulations of amphotericin B in comparison with conventional medications. In addition, we explore the possibility of using voriconazole as the primary treatment for invasive infections such as aspergillosis, as well as those caused by Scedosporium spp. and Fusarium spp., together with that of using caspofungin to treat disseminated candidiasis and invasive aspergillosis.


Assuntos
Humanos , Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Pneumopatias Fúngicas/tratamento farmacológico , Peptídeos Cíclicos/uso terapêutico , Pirimidinas/uso terapêutico , Triazóis/uso terapêutico , Anfotericina B/efeitos adversos , Antifúngicos/efeitos adversos , Equinocandinas , Peptídeos Cíclicos/efeitos adversos , Pirimidinas/efeitos adversos , Triazóis/efeitos adversos
19.
P. R. health sci. j ; 24(2): 157-160, Jun. 2005.
Artigo em Inglês | LILACS | ID: lil-472965

RESUMO

The incidence of severe fungal infections in the immunocompromised patient with malignancies has increased in recent years. This appears to be associated to the profound periods of immunosuppression and the extended use of broad spectrum antibiotics. Aspergillosis is the second most common fungal infection reported in the immunocompromised cancer patients. In patients with advanced immunosupression, the mortality due to invasive aspergillosis approaches 100despite treatment with antifungal agents. Reports of complete or partial response to echinocandins are well demonstrated in adults, but very limited in the pediatric population. This report describes the case of a child with relapsed acute lymphoblastic leukemia (ALL) who developed cutaneous aspergillosis and subsequent multiorgan dissemination during therapeutic induction and was treated successfuly with caspofungin acetate.


Assuntos
Humanos , Feminino , Criança , Aspergilose/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Antifúngicos/uso terapêutico , Aspergillus/isolamento & purificação , Aspergilose/diagnóstico , Aspergilose/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Peptídeos Cíclicos/uso terapêutico , Resultado do Tratamento
20.
Medicina (B.Aires) ; 64(2): 152-154, 2004.
Artigo em Espanhol | LILACS | ID: lil-444338

RESUMO

Fungal endocarditis, in particular due to Candida species, requires medical and surgical treatment and amphotericin B is the drug of choice. Caspofungin is an echinocandin very effective against Candida and Aspergillus. We present a patient with Candida tropicalis endocarditis, fluconazol resistant, treated with caspofungin, on a compassional basis as a result of adverse effects with amphotericin B. The patient had a microbiological response.


Las endocarditis causadas por hongos, (Candida en particular), requieren tratamiento médico-quirúrgico,siendo la anfotericina B la droga de elección. Caspofungina es una equinocandina con gran actividadsobre Candida y Aspergillus. Se presenta un paciente con una endocarditis por Candida tropicalis resistente a fluconazol tratado con caspofungina bajo un esquema de salvataje, luego de haber presentado efectos adversos por anfotericina B. El paciente tuvo respuesta microbiológica.


Assuntos
Idoso , Humanos , Masculino , Antifúngicos/uso terapêutico , Candida tropicalis/efeitos dos fármacos , Candidíase/tratamento farmacológico , Endocardite/tratamento farmacológico , Fluconazol/uso terapêutico , Peptídeos Cíclicos/uso terapêutico , Candidíase/complicações , Endocardite/microbiologia , Evolução Fatal , Farmacorresistência Fúngica
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA