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1.
J Int Med Res ; 52(3): 3000605241237878, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38530040

RESUMO

OBJECTIVES: We assessed the efficacy of a 3-week primary or salvage caspofungin regimen in patients with chronic obstructive pulmonary disease (COPD) and concomitant proven or suspected invasive pulmonary aspergillosis (IPA). METHODS: Forty-four patients were treated with an initial loading caspofungin dose of 70 mg, followed by a daily dose of 50 mg for 20 days. The main efficacy endpoint was clinical effectiveness. Secondary endpoints included the clinical efficacy of caspofungin after 1 week, therapeutic efficacy based on the European Organization for Research and Treatment of Cancer and Mycoses Study Group Education and Research Consortium (EORTC/MSG) criteria, the sensitivity of different Aspergillus strains to caspofungin in vitro, and the safety of caspofungin. RESULTS: An assessment of 42 patients in the intention-to-treat group revealed efficacy rates of 33.33% within 1 week and 38.10% within 3 weeks. According to the EORTC/MSG criteria, the treatment success rate was 38.10%. The success rate of first-line treatment was 54.76%, whereas salvage treatment had a success rate of 45.24%. No adverse events were reported among the participants. CONCLUSIONS: Caspofungin is effective and safe as an initial or salvage treatment for patients with IPA and COPD.


Assuntos
Aspergilose , Aspergilose Pulmonar Invasiva , Doença Pulmonar Obstrutiva Crônica , Humanos , Caspofungina/uso terapêutico , Aspergilose Pulmonar Invasiva/complicações , Aspergilose Pulmonar Invasiva/tratamento farmacológico , Aspergilose Pulmonar Invasiva/induzido quimicamente , Antifúngicos/efeitos adversos , Equinocandinas/efeitos adversos , Lipopeptídeos/uso terapêutico , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico
2.
Int J Antimicrob Agents ; 63(1): 107058, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38081549

RESUMO

OBJECTIVES: Invasive Aspergillus infections during the early phase of childhood acute lymphoblastic leukemia (ALL) treatment come with morbidity and mortality. The interaction with vincristine hampers first-line azole prophylaxis. We describe the efficacy of an alternative twice-a-week micafungin regimen for Aspergillus prophylaxis. METHODS: Newly diagnosed paediatric patients with ALL treated according to the ALL-11 protocol received micafungin twice-a-week (9 mg/kg/dose [max. 300 mg]) during the induction course (first 35 days of treatment) as part of routine care. A historical control cohort without Aspergillus prophylaxis was used. During the first consolidation course (day 36-79), standard itraconazole prophylaxis was used in both groups. The percentage of proven/probable Aspergillus infections during the induction/first consolidation course was compared between the cohorts. The cumulative incidence of proven/probable Aspergillus infections was estimated using a competing risk model. For safety evaluation, liver laboratory chemistry values were analysed. RESULTS: A total of 169 and 643 paediatric patients with ALL were treated in the micafungin cohort (median age: 4 years [range 1-17]) and historical cohort (median age: 5 years [range 1-17]). The percentage of proven/probable Aspergillus infections was 1·2% (2/169) in the micafungin cohort versus 5·8% (37/643) in the historical cohort (p=0.013; Fisher's exact test). The differences in estimated cumulative incidence were assessed (p=0·014; Gray's test). Although significantly higher ALT/AST values were reported in the micafungin cohort, no clinically relevant side effects were observed. CONCLUSIONS: Twice-a-week micafungin prophylaxis during the induction course significantly reduced the occurrence of proven/probable Aspergillus infections in the early phase of childhood ALL treatment.


Assuntos
Aspergilose , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Criança , Lactente , Pré-Escolar , Adolescente , Micafungina/uso terapêutico , Antifúngicos/farmacologia , Equinocandinas/efeitos adversos , Estudos de Coortes , Lipopeptídeos/uso terapêutico , Lipopeptídeos/farmacologia , Aspergilose/tratamento farmacológico , Aspergilose/prevenção & controle , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/induzido quimicamente
3.
Bioorg Med Chem Lett ; 97: 129569, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-38008340

RESUMO

Interaction between Middle East respiratory syndrome coronavirus (MERS-CoV) spike (S) protein heptad repeat-1 domain (HR1) and heptad repeat-2 domain (HR2) is critical for the MERS-CoV fusion process. This interaction is mediated by the α-helical region from HR2 and the hydrophobic groove in a central HR1 trimeric coiled coil. We sought to develop a short peptidomimetic to act as a MERS-CoV fusion inhibitor by reproducing the key recognition features of HR2 helix. This was achieved by the use of helix-stabilizing strategies, including substitution with unnatural helix-favoring amino acids, introduction of ion pair interactions, and conjugation of palmitic acid. The resulting 23-mer lipopeptide, termed AEEA-C16, inhibits MERS-CoV S protein-mediated cell-cell fusion at a low micromolar level comparable to that of the 36-mer HR2 peptide HR2P-M2. Collectively, our studies provide new insights into developing short peptide-based antiviral agents to treat MERS-CoV infection.


Assuntos
Antivirais , Coronavírus da Síndrome Respiratória do Oriente Médio , Antivirais/farmacologia , Antivirais/química , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos dos fármacos , Peptídeos/química , Conformação Proteica em alfa-Hélice , Lipopeptídeos/farmacologia , Lipopeptídeos/uso terapêutico
4.
J Chemother ; 35(8): 721-729, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37190751

RESUMO

The objective of this study was to evaluate the efficacy of various micafungin dosing regimens against Candida spp. in pediatric patients undergoing hematopoietic stem cell transplantation (HSCT). Monte Carlo simulations were conducted using pharmacokinetic (PK) parameters and pharmacodynamic (PD) data to determine the probabilities of target attainment and cumulative fractions of response in terms of area under the concentration curve/minimum inhibition concentration targets of micafungin. Current standard clinical micafungin dosing regimens of 1 and 2 mg/kg/day were appropriate for the prevention and treatment of Candida glabrata infection in pediatric patients undergoing HSCT, respectively. Moreover, the high-dose prophylactic dosage (2 mg/kg/day) and therapeutic dosage (4 mg/kg/day) should be the preferred option to optimize efficacy against Candida albicans. However, none of the simulated regimens was effective against Candida parapsilosis in pediatric HSCT patients. These PK/PD-based simulations rationalize and optimize the micafungin dosing regimens against Candida spp. in pediatric patients undergoing HSCT.


Assuntos
Candidíase , Transplante de Células-Tronco Hematopoéticas , Humanos , Criança , Micafungina/farmacologia , Candida , Antifúngicos/uso terapêutico , Equinocandinas/uso terapêutico , Método de Monte Carlo , Candidíase/tratamento farmacológico , Testes de Sensibilidade Microbiana , Lipopeptídeos/uso terapêutico
5.
J Control Release ; 351: 245-254, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36108811

RESUMO

Transdermal administration of chemotherapeutics into tumor tissues may be an effective treatment to reduce toxic side effects and improve patient compliance for melanoma. Herein, we report a multistage transdermal drug delivery system for chemotherapy of melanoma. In this system, dendritic lipopeptide (DLP) modified multistage targeted liposomes (Mtlip) were incorporated into the hydrogel matrix to achieve localized and sustained drug release; Ultra-deformability of Mtlip can pass through dense stratum corneum to the epidermis where melanoma is located; Virus-mimicking Mtlip enhances the payload in tumor tissues by high permeability; The positive charged Mtlip can improve cell uptake efficiency and selectively accumulate into mitochondria to increases toxic. The efficacy of this type of multistage targeted liposomes loaded hydrogel in treating melanoma was systematically evaluated both in vitro and in vivo.


Assuntos
Lipossomos , Melanoma , Humanos , Hidrogéis/uso terapêutico , Sistemas de Liberação de Medicamentos , Lipopeptídeos/uso terapêutico , Melanoma/metabolismo , Administração Cutânea
6.
J Hepatol ; 77(6): 1525-1531, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35973578

RESUMO

BACKGROUND & AIMS: Bulevirtide (BLV) has recently been conditionally approved for the treatment of chronic hepatitis delta (CHD) in Europe, but its effectiveness and safety in patients with compensated cirrhosis and clinically significant portal hypertension (CSPH) are unknown. METHODS: Consecutive patients with HDV-related compensated cirrhosis and CSPH who started BLV 2 mg/day were enrolled in this single-center study. Clinical/virological characteristics were collected at baseline, weeks 4, 8 and every 8 weeks thereafter. HDV RNA was quantified by Robogene 2.0 (lower limit of detection 6 IU/ml). RESULTS: Eighteen Caucasian patients with compensated cirrhosis and CSPH under nucleos(t)ide analogue treatment were enrolled: median (IQR) age was 48 (29-77) years, and 67% were male. Median (IQR) platelet count was 70 (37-227) x103/µl, liver stiffness measurement (LSM) 16.4 (7.8-57.8) kPa, alanine aminotransferase (ALT) 106 (32-222) U/L, HBsAg 3.7 (2.5-4.3) log IU/ml, HDV RNA 4.9 (3.3-6.6) log IU/ml. During 48 weeks of BLV monotherapy, HDV RNA declined by 3.1 (0.2-4.3) log IU/ml (p <0.001 vs. baseline), becoming undetectable in 5 patients (23%). A virological response was observed in 14 (78%) patients while a non-response was observed in 2 (11%). ALT decreased to 35 (15-86) U/L (p <0.001 vs. baseline), normalizing in 83% of patients. A combined response was observed in 67% of patients. Aspartate aminotransferase and gamma-glutamyltransferase levels significantly improved. Concerning liver function parameters, albumin values significantly increased and bilirubin remained stable. LSM significantly improved in patients with virological response, while platelet count was unchanged. None of the patients developed decompensating events or hepatocellular carcinoma. BLV was well tolerated, no patient discontinued treatment and the increase in bile acids was fully asymptomatic. CONCLUSIONS: A 48-week course of BLV 2 mg/day monotherapy is safe and effective even for difficult-to treat patients with HDV-related compensated cirrhosis and CSPH. LAY SUMMARY: Hepatitis delta virus (HDV) is associated with the most severe form of viral hepatitis. A new treatment for HDV called bulevirtide has recently received conditional approval for patients with chronic HDV infection. However, its safety and effectiveness in patients with more advanced liver disease is not known. Herein, we show that it is safe and effective in patients with HDV-related cirrhosis and clinically significant portal hypertension.


Assuntos
Antivirais , Hepatite D , Hipertensão Portal , Lipopeptídeos , Neoplasias Hepáticas , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Antivirais/uso terapêutico , Hepatite D/complicações , Hepatite D/tratamento farmacológico , Vírus Delta da Hepatite/genética , Hipertensão Portal/complicações , Hipertensão Portal/tratamento farmacológico , Cirrose Hepática/complicações , Cirrose Hepática/tratamento farmacológico , Adulto , Lipopeptídeos/uso terapêutico
7.
Peptides ; 155: 170836, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35803360

RESUMO

Surfactins are cyclic lipopeptides that are isolated from various Bacillus strains. They are made up of heptapeptides and ß-hydroxy fatty acids of variable chain lengths of carbon atoms. Therapeutically they are known to inhibit invasion, migration, and colony formation of human breast carcinoma cells. The role of surfactins is also known as anti-proliferative agents against human cancer cells through induction of apoptosis, arrest of the cell cycle, or suppression of survival signaling. The cytotoxic activity of surfactins is also perceived against human chronic myelogenous leukemia cells, human colon cancer cells, and hepatic carcinoma cells. Considering the wide spectrum of targets, the molecular effects of surfactins are diverse in different cancer cells and they can serve as promising chemotherapeutic agents for the treatment of cancer. Surfactins are being delivered to the targeted cancer cells through nano-carriers or nano-formulations. The present review article provides insight on different types and variations of surfactins, their molecular effect on different cancer cells, and their therapeutic use in the treatment of human cancer.


Assuntos
Antineoplásicos , Neoplasias , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Bacillus subtilis/química , Bacillus subtilis/metabolismo , Humanos , Lipopeptídeos/química , Lipopeptídeos/farmacologia , Lipopeptídeos/uso terapêutico , Neoplasias/tratamento farmacológico , Peptídeos Cíclicos/farmacologia
8.
Biochim Biophys Acta Mol Cell Res ; 1869(1): 119144, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34599981

RESUMO

Osimertinib, as the third-generation EGFR tyrosine kinase inhibitors (EGFR-TKIs), is a first-line molecularly targeted drug for non-small cell lung cancer (NSCLC). However, the emergence of therapeutic resistance to osimertinib markedly impairs its efficiency and efficacy, leading to the failure of clinical applications. Novel molecular targets and drugs are urgently needed for reversing osimertinib resistance in NSCLC. Protease-activated receptor 2 (PAR2) that belongs to a subfamily of G protein-coupled receptors can stimulate the transactivation of EGFR to regulate multiple cellular signalling, actively participating in tumour progression. This study firstly discovered that PAR2 expression was notably enhanced when NSCLC cells became resistant to osimertinib. A PAR2 inhibitor facilitated osimertinib to attenuate EGFR transactivation, ERK phosphorylation, EMT and PD-L1 expression which were associated to osimertinib resistance. The combination of the PAR2 inhibitor and osimertinib also notably blocked cell viability, migration, 3D sphere formation and in vivo tumour growth whereas osimertinib itself lost such inhibitory effects in osimertinib-resistant NSCLC cells. Importantly, this reversal effect of PAR2 blockade was uncovered to depend on ERK-mediated EMT and PD-L1, since inhibition of ß-arrestin or ERK, which could be modulated by PAR2, sensitized osimertinib to prevent EMT, PD-L1 expression and consequently overcame osimertinib resistance. Thus, this study demonstrated that PAR2 antagonism could limit ERK-mediated EMT and immune checkpoints, consequently attenuating EGFR transactivation and reactivate osimertinib. It suggested that PAR2 may be a novel drug target for osimertinib resistance, and PAR2 inhibition may be a promising strategy candidate for reversing EGFR-TKI resistance in NSCLC.


Assuntos
Antígeno B7-H1/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Receptor PAR-2/antagonistas & inibidores , Acrilamidas/farmacologia , Acrilamidas/uso terapêutico , Compostos de Anilina/farmacologia , Compostos de Anilina/uso terapêutico , Animais , Antígeno B7-H1/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Lipopeptídeos/farmacologia , Lipopeptídeos/uso terapêutico , Neoplasias Pulmonares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Receptor PAR-2/metabolismo
9.
Int J Mol Sci ; 22(20)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34681717

RESUMO

The immunosuppressive character of head and neck cancers may explain the relatively low response rates to antibody therapy targeting a tumor antigen, such as cetuximab, and anti-PD-1 checkpoint inhibition. Immunostimulatory agents that overcome tumor-derived inhibitory signals could augment therapeutic efficacy, thereby enhancing tumor elimination and improving patient survival. Here, we demonstrate that cetuximab treatment combined with immunostimulatory agonists for Toll-like receptor (TLR) 2 induces profound immune responses. Natural killer (NK) cells, isolated from healthy individuals or patients with head and neck cancer, harbored enhanced cytotoxic capacity and increased tumor-killing potential in vitro. Additionally, combination treatment increased the release of several pro-inflammatory cytokines and chemokines by NK cells. Tumor-bearing mice that received cetuximab and the TLR2 ligand Pam3CSK4 showed increased infiltration of immune cells into the tumors compared to mice that received cetuximab monotherapy, resulting in a significant delay in tumor growth or even complete tumor regression. Moreover, combination treatment resulted in improved overall survival in vivo. In conclusion, combining tumor-targeting antibody-based immunotherapy with TLR stimulation represents a promising treatment strategy to improve the clinical outcomes of cancer patients. This treatment could well be applied together with other therapeutic strategies such as anti-PD-(L)1 checkpoint inhibition to further overcome immunosuppression.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos/imunologia , Neoplasias de Cabeça e Pescoço/terapia , Células Matadoras Naturais/imunologia , Receptor 2 Toll-Like/agonistas , Animais , Linhagem Celular Tumoral , Cetuximab/farmacologia , Cetuximab/uso terapêutico , Citocinas/metabolismo , Quimioterapia Combinada , Feminino , Humanos , Imunoterapia , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Lipopeptídeos/farmacologia , Lipopeptídeos/uso terapêutico , Camundongos , Camundongos Nus , Receptores de IgG/agonistas , Receptores de IgG/metabolismo , Receptor 2 Toll-Like/metabolismo , Transplante Heterólogo
10.
J Viral Hepat ; 28(6): 852-858, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33599010

RESUMO

With extensive research on the pathogenesis and treatment of hepatitis B virus (HBV) and hepatitis D virus (HDV) infections, the current treatment of interferon and nucleoside or nucleotide analogues provides reasonable control of viral replication in chronic hepatitis B (CHB). However, drug resistance may occur as a result of long-term treatment, and continuous covalently closed circular DNA (cccDNA) can cause disease relapse after drug withdrawal. Therefore, there is an urgent need for safe and effective antiviral drugs or methods to treat HBV and HDV infections. Myrcludex B is the first entry inhibitor that can inactivate HBV and HDV receptors, compete with HBV for the sodium-taurocholate co-transporting polypeptide, which has been identified as the bona fide receptor for HBV and HDV, block HBV infection in hepatocytes, and participate in HBV transcriptional suppression. Myrcludex B plays an important role in the inhibition of HBV replication and is a potential drug for phase III clinical trials. In this article, we review the progress on the efficacy and clinical application of myrcludex B in recent years.


Assuntos
Hepatite B , Hepatite D , Antivirais/farmacologia , Antivirais/uso terapêutico , Hepatite B/tratamento farmacológico , Vírus da Hepatite B , Hepatite D/tratamento farmacológico , Vírus Delta da Hepatite/genética , Hepatócitos , Humanos , Lipopeptídeos/uso terapêutico
11.
JCI Insight ; 6(5)2021 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33561017

RESUMO

The impact of respiratory virus infections on global health is felt not just during a pandemic, but endemic seasonal infections pose an equal and ongoing risk of severe disease. Moreover, vaccines and antiviral drugs are not always effective or available for many respiratory viruses. We investigated how induction of effective and appropriate antigen-independent innate immunity in the upper airways can prevent the spread of respiratory virus infection to the vulnerable lower airways. Activation of TLR2, when restricted to the nasal turbinates, resulted in prompt induction of innate immune-driven antiviral responses through action of cytokines, chemokines, and cellular activity in the upper but not the lower airways. We have defined how nasal epithelial cells and recruitment of macrophages work in concert and play pivotal roles to limit progression of influenza virus to the lungs and sustain protection for up to 7 days. These results reveal underlying mechanisms of how control of viral infection in the upper airways can occur and support the implementation of strategies that can activate TLR2 in nasal passages to provide rapid protection, especially for at-risk populations, against severe respiratory infection when vaccines and antiviral drugs are not always effective or available.


Assuntos
Imunidade Inata/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Influenza Humana , Lipopeptídeos/farmacologia , Pulmão , Infecções Respiratórias , Receptor 2 Toll-Like/metabolismo , Animais , Antivirais/farmacologia , Antivirais/uso terapêutico , Modelos Animais de Doenças , Feminino , Humanos , Fatores Imunológicos/uso terapêutico , Vírus da Influenza A , Influenza Humana/tratamento farmacológico , Influenza Humana/imunologia , Influenza Humana/metabolismo , Influenza Humana/virologia , Lipopeptídeos/uso terapêutico , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/virologia , Masculino , Camundongos Endogâmicos C57BL , Infecções por Orthomyxoviridae/tratamento farmacológico , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/metabolismo , Infecções por Orthomyxoviridae/virologia , Sistema Respiratório/efeitos dos fármacos , Sistema Respiratório/imunologia , Sistema Respiratório/metabolismo , Sistema Respiratório/virologia , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/imunologia , Infecções Respiratórias/metabolismo , Infecções Respiratórias/virologia , Receptor 2 Toll-Like/agonistas
13.
Int J Mol Sci ; 21(19)2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32977579

RESUMO

Microbial surfactants (biosurfactants) are a broad category of surface-active biomolecules with multifunctional properties. They self-assemble in aqueous solutions and are adsorbed on various interfaces, causing a decrease in surface tension, as well as interfacial tension, solubilization of hydrophobic compounds, and low critical micellization concentrations. Microbial biosurfactants have been investigated and applied in several fields, including bioremediation, biodegradation, food industry, and cosmetics. Biosurfactants also exhibit anti-microbial, anti-biofilm, anti-cancer, anti-inflammatory, wound healing, and immunomodulatory activities. Recently, it has been reported that biosurfactants can increase the immune responses and disease resistance of fish. Among various microbial surfactants, lipopeptides, glycolipids, and phospholipids are predominantly investigated. This review presents the various immunological activities of biosurfactants, mainly glycolipids and lipopeptides. The applications of biosurfactants in aquaculture, as well as their immunomodulatory activities, that make them novel therapeutic candidates have been also discussed in this review.


Assuntos
Doenças dos Peixes , Peixes/imunologia , Glicolipídeos , Lipopeptídeos , Tensoativos , Animais , Doenças dos Peixes/tratamento farmacológico , Doenças dos Peixes/imunologia , Pesqueiros , Glicolipídeos/química , Glicolipídeos/uso terapêutico , Lipopeptídeos/química , Lipopeptídeos/uso terapêutico , Tensoativos/química , Tensoativos/uso terapêutico
14.
ChemMedChem ; 15(20): 1887-1896, 2020 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-32767819

RESUMO

Antimicrobial peptides are ubiquitous in multicellular organisms and have served as defense mechanisms for their successful evolution and throughout their life cycle. These peptides are short cationic amphiphilic polypeptides of fewer than 50 amino acids containing either a few disulfide-linked cysteine residues with a characteristic ß-sheet-rich structure or linear α-helical conformations with hydrophilic side chains at one side of the helix and hydrophobic side chains on the other side. Antimicrobial peptides cause bacterial cell lysis either by direct cell-surface damage via electrostatic interactions between the cationic side chains of the peptide and the negatively charged cell surface, or by indirect modulation of the host defense systems. Electrostatic interactions lead to bacterial cell membrane disruption followed by leakage of cellular components and finally bacterial cell death. Because of their unusual mechanism of cell damage, antimicrobial peptides are effective against drug-resistant bacteria and may therefore prove more effective than classical antibiotics in certain cases. Currently, around 3000 natural antimicrobial peptides from six kingdoms (bacteria, archaea, protists, fungi, plants, and animals) have been isolated and sequenced. However, only a few of them are under clinical trials and/or in the commercial development stage for the treatment of bacterial infections caused by antibiotic-resistant bacteria. Moreover, high structural complexity, poor pharmacokinetic properties, and low antibacterial activity of natural antimicrobial peptides hinder their progress in drug development. To overcome these hurdles, researchers have become increasingly interested in modification and nature-inspired synthetic antimicrobial peptides. This review discusses some of the recent studies reported on antimicrobial peptides.


Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Sequência de Aminoácidos , Antibacterianos/química , Antibacterianos/uso terapêutico , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Bactérias/efeitos dos fármacos , Ensaios Clínicos como Assunto , Humanos , Lipopeptídeos/química , Lipopeptídeos/farmacologia , Lipopeptídeos/uso terapêutico , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/uso terapêutico , Peptidomiméticos/química , Peptidomiméticos/farmacologia , Peptidomiméticos/uso terapêutico , Conformação Proteica em alfa-Hélice
15.
Mol Pharm ; 17(6): 2125-2134, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32348151

RESUMO

The cationic glycopeptide bleomycin (BLM) is a broad-spectrum chemotherapy drug clinically applied to treat various malignant tumors. The poor cell membrane permeability of BLM, which is prone to high dose usage and may consequently induce dose-dependent lung toxicity, is a sticking point to limit clinical applications of BLM. As a commercial biosurfactant, the anionic lipopeptide surfactin (SF) is well known for its potent ability to disturb membranes and widely applied in cosmetic area as a permeabilization synergist. In this work, our in vitro investigations showed that SF could ameliorate the cell internalization of BLM, and the combined usage of SF notably improved the antitumor activity of BLM or its analogues while having no obvious effects on normal cells. Subsequent in vivo assessments on the subcutaneous treatment of A375 melanoma in mice demonstrated that SF could also enhance the therapeutic effects of BLM family compounds in subeffective doses, with no obvious toxicities on lungs and skin. Also, our preliminary results suggested the formation of complex micelles at the nanoscale by the self-assembly of BLM and SF, which may contribute to the ameliorated internalization and the antitumor effect of BLM. Therefore, SF could be applied as a potential synergist for BLM to reduce its treatment dose while maintaining the therapeutic effect on treatment of skin carcinoma, which provides us an alternative way to minimize the side effects of clinical BLM and facilitate the development of new BLM-type drugs.


Assuntos
Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Bleomicina/farmacologia , Bleomicina/uso terapêutico , Lipopeptídeos/farmacologia , Lipopeptídeos/uso terapêutico , Melanoma/tratamento farmacológico , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/uso terapêutico , Células A549 , Animais , Feminino , Humanos , Masculino , Melanoma/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Espécies Reativas de Oxigênio/metabolismo
16.
Cell Mol Gastroenterol Hepatol ; 10(3): 451-466, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32330730

RESUMO

BACKGROUND & AIMS: Bile acids are important metabolic signaling molecules. Bile acid receptor activation promotes body weight loss and improves glycemic control. The incretin hormone GLP-1 and thyroid hormone activation of T4 to T3 have been suggested as important contributors. Here, we identify the hepatic bile acid uptake transporter Na+ taurocholate co-transporting polypeptide (NTCP) as target to prolong postprandial bile acid signaling. METHODS: Organic anion transporting polypeptide (OATP)1a/1b KO mice with or without reconstitution with human OATP1B1 in the liver were treated with the NTCP inhibitor Myrcludex B for 3.5 weeks after the onset of obesity induced by high fat diet-feeding. Furthermore, radiolabeled T4 was injected to determine the role of NTCP and OATPs in thyroid hormone clearance from plasma. RESULTS: Inhibition of NTCP by Myrcludex B in obese Oatp1a/1b KO mice inhibited hepatic clearance of bile acids from portal and systemic blood, stimulated GLP-1 secretion, reduced body weight, and decreased (hepatic) adiposity. NTCP inhibition did not affect hepatic T4 uptake nor lead to increased thyroid hormone activation. Myrcludex B treatment increased fecal energy output, explaining body weight reductions amongst unaltered food intake and energy expenditure. CONCLUSIONS: Pharmacologically targeting hepatic bile acid uptake to increase bile acid signaling is a novel approach to treat obesity and induce GLP1- secretion.


Assuntos
Ácidos e Sais Biliares/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Lipopeptídeos/farmacologia , Obesidade/tratamento farmacológico , Transportadores de Ânions Orgânicos Dependentes de Sódio/antagonistas & inibidores , Simportadores/antagonistas & inibidores , Animais , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Feminino , Humanos , Lipopeptídeos/uso terapêutico , Fígado/efeitos dos fármacos , Fígado/metabolismo , Transportador 1 de Ânion Orgânico Específico do Fígado/genética , Masculino , Camundongos , Camundongos Transgênicos , Obesidade/etiologia , Proteínas de Transporte de Cátions Orgânicos/genética
17.
Mar Drugs ; 18(3)2020 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-32210159

RESUMO

Jahanyne, a lipopeptide with a unique terminal alkynyl and OEP (2-(1-oxo-ethyl)-pyrrolidine) moiety, exhibits anticancer activity. We synthesized jahanyne and analogs modified at the OEP moiety, employing an α-fluoromethyl ketone (FMK) strategy. Preliminary bioassays indicated that compound 1b (FMK-jahanyne) exhibited decreased activities to varying degrees against most of the cancer cells tested, whereas the introduction of a fluorine atom to the α-position of a hydroxyl group (2b) enhanced activities against all lung cancer cells. Moreover, jahanyne and 2b could induce G0/G1 cell cycle arrest in a concentration-dependent manner.


Assuntos
Desenho de Fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Lipopeptídeos/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Apoptose/efeitos dos fármacos , Organismos Aquáticos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cianobactérias/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Lipopeptídeos/síntese química , Lipopeptídeos/uso terapêutico , Neoplasias Pulmonares/patologia , Estrutura Molecular , Relação Estrutura-Atividade
18.
Biomater Sci ; 8(4): 1101-1105, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-31793928

RESUMO

For mRNA mediated cancer immunotherapy, Pam3 was incorporated as an adjuvant within lipid nanoparticles (LNPs) with OVA mRNA. The developed Pam3 incorporated LNPs showed successful expression of tumor antigens with enhanced immune stimulation. We demonstrated that the synergies of Pam3 LNPs could greatly improve the efficacy of tumor prevention by mRNA vaccines.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Lipopeptídeos/administração & dosagem , Neoplasias/tratamento farmacológico , Ovalbumina/genética , RNA Mensageiro/administração & dosagem , Adjuvantes Imunológicos/química , Animais , Vacinas Anticâncer/administração & dosagem , Vacinas Anticâncer/uso terapêutico , Linhagem Celular , Humanos , Imunoterapia , Injeções Intramusculares , Lipídeos/química , Lipopeptídeos/química , Lipopeptídeos/uso terapêutico , Camundongos , Nanopartículas , Neoplasias/imunologia , Tamanho da Partícula , RNA Mensageiro/química , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Korean J Gastroenterol ; 74(5): 267-273, 2019 Nov 25.
Artigo em Coreano | MEDLINE | ID: mdl-31765555

RESUMO

A HBV infection is a dynamic disease and long-term liver inflammation contributes to the development of liver cirrhosis and hepatocellular carcinoma. Currently available nucleos(t)ide analogues and pegylated interferon are effective in inhibiting HBV replication but rarely achieve HBsAg clearance. The present article introduces a new definition of HBV cure and several emerging therapies for HBV cure, including direct acting antivirals and immune modulatory antivirals.


Assuntos
Hepatite B Crônica/tratamento farmacológico , Antivirais/farmacologia , Antivirais/uso terapêutico , Edição de Genes , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/genética , Vírus da Hepatite B/fisiologia , Humanos , Lipopeptídeos/farmacologia , Lipopeptídeos/uso terapêutico , RNA Interferente Pequeno/farmacologia , RNA Interferente Pequeno/uso terapêutico , Montagem de Vírus/efeitos dos fármacos , Internalização do Vírus/efeitos dos fármacos
20.
World J Gastroenterol ; 25(32): 4580-4597, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31528088

RESUMO

Chronic delta hepatitis is the most severe form of viral hepatitis affecting nearly 65 million people worldwide. Individuals with this devastating illness are at higher risk for developing cirrhosis and hepatocellular carcinoma. Delta virus is a defective RNA virus that requires hepatitis B surface antigen for propagation in humans. Infection can occur in the form of a co-infection with hepatitis B, which can be self-limiting, vs superinfection in a patient with established hepatitis B infection, which often leads to chronicity in majority of cases. Current noninvasive tools to assess for advanced liver disease have limited utility in delta hepatitis. Guidelines recommend treatment with pegylated interferon, but this is limited to patients with compensated disease and is efficacious in about 30% of those treated. Due to limited treatment options, novel agents are being investigated and include entry, assembly and export inhibitors of viral particles in addition to stimulators of the host immune response. Future clinical trials should take into consideration the interaction of hepatitis B and hepatitis D as suppression of one virus can lead to the activation of the other. Also, surrogate markers of treatment efficacy have been proposed.


Assuntos
Antivirais/uso terapêutico , Coinfecção/tratamento farmacológico , Hepatite B Crônica/tratamento farmacológico , Hepatite D Crônica/tratamento farmacológico , Superinfecção/tratamento farmacológico , Terapias em Estudo/métodos , Antivirais/farmacologia , Coinfecção/epidemiologia , Coinfecção/virologia , Quimioterapia Combinada/métodos , Carga Global da Doença , Antígenos de Superfície da Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/metabolismo , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/epidemiologia , Hepatite B Crônica/virologia , Hepatite D Crônica/epidemiologia , Hepatite D Crônica/virologia , Vírus Delta da Hepatite/imunologia , Vírus Delta da Hepatite/patogenicidade , Humanos , Interferon-alfa/farmacologia , Interferon-alfa/uso terapêutico , Lipopeptídeos/farmacologia , Lipopeptídeos/uso terapêutico , Transportadores de Ânions Orgânicos Dependentes de Sódio/antagonistas & inibidores , Transportadores de Ânions Orgânicos Dependentes de Sódio/metabolismo , Piperidinas/farmacologia , Piperidinas/uso terapêutico , Piridinas/farmacologia , Piridinas/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Literatura de Revisão como Assunto , Superinfecção/epidemiologia , Superinfecção/virologia , Simportadores/antagonistas & inibidores , Simportadores/metabolismo , Resultado do Tratamento , Montagem de Vírus/efeitos dos fármacos , Internalização do Vírus/efeitos dos fármacos
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