RESUMO
Lung infection is the leading cause of morbidity and mortality in cystic fibrosis (CF) patients and is mainly dominated by Pseudomonas aeruginosa. Treatment of CF-associated lung infections is problematic because the drugs are vulnerable to multidrug-resistant pathogens, many of which are major biofilm producers like P. aeruginosa. Antimicrobial peptides (AMPs) are essential components in all life forms and exhibit antimicrobial activity. Here we investigated a series of AMPs (d,l-K6L9), each composed of six lysines and nine leucines but differing in their sequence composed of l- and d-amino acids. The d,l-K6L9 peptides showed antimicrobial and antibiofilm activities against P. aeruginosa from CF patients. Furthermore, the data revealed that the d,l-K6L9 peptides are stable and resistant to degradation by CF sputum proteases and maintain their activity in a CF sputum environment. Additionally, the d,l-K6L9 peptides do not induce bacterial resistance. Overall, these findings should assist in the future development of alternative treatments against resistant bacterial biofilms.
Assuntos
Anti-Infecciosos , Fibrose Cística , Infecções por Pseudomonas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/uso terapêutico , Peptídeos Antimicrobianos , Biofilmes , Fibrose Cística/tratamento farmacológico , Humanos , Testes de Sensibilidade Microbiana , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosaRESUMO
The present work describes the synthesis, characterization, and anticancer properties of c(Lys-Pro), P1; c(Orn-Pro), P2; and conjugates PA-c(Lys-Pro), C1; PA-c(Orn-Pro), C2; EPA-c(Lys-Pro), C3; and EPA-c(Orn-Pro), C4. Among all, conjugate C4 displays potent anticancer activity with IC50 1.3 µM in MDA-MB-231, 3.5 µM in PC-3, 8.9 µM in MCF-7, and 9.6 µM in Miapaca-2 cancer cells. In addition, C4 downregulates the expression of MDM2 and abrogates the cancer cell invasion/metastasis. Through knock-down of MDM2, we demonstrate that this abrogation of metastasis by C4 is primarily MDM2 dependent. Furthermore, the animal studies underscore the antitumor as well as antimetastatic potential of C4 in vivo in breast cancer model at a safe and tolerable dose of 20 mg/kg.
Assuntos
Antineoplásicos/química , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Metástase Neoplásica/prevenção & controle , Peptídeos Cíclicos/química , Peptídeos Cíclicos/uso terapêutico , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Animais , Antineoplásicos/farmacologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Ácidos Graxos Insaturados/química , Ácidos Graxos Insaturados/farmacologia , Ácidos Graxos Insaturados/uso terapêutico , Feminino , Técnicas de Silenciamento de Genes , Células HCT116 , Humanos , Células MCF-7 , Camundongos Endogâmicos BALB C , Invasividade Neoplásica/patologia , Invasividade Neoplásica/prevenção & controle , Metástase Neoplásica/patologia , Peptídeos Cíclicos/farmacologia , Proteínas Proto-Oncogênicas c-mdm2/genéticaRESUMO
The peptides containing ß- and γ-amino acids, LA-Lys-PEA, P1; LA-Lys-ß3,3-Ac6c-PEA, P2; LA-Orn-ß3,3-Ac6c-PEA, P3; LA-Lys-Gpn-PEA, P4; LA-Orn-Gpn-PEA, P5; LA-Lys-γ4-Phe-PEA, P6, LA-γ4-Leu-Lys-PEA, P7 and LA-ß3,3-Pip(Ac)-Lys-PEA, P8 were synthesized, characterized and evaluated against Gram-positive and Gram-negative bacteria. Among all, peptides P2, P3, P4 and P5 exhibited potent activity (MIC 6.25µM) against S. aureus MTCC 737 and P. aeruginosa MTCC 424. In order to understand the efficacy of peptides and mechanism of action, time kill kinetics and fluorescence microscopic studies were performed against S. aureus and P. aeruginosa for the peptides P2, P3, P4 and P5. P4 took half time to show the bactericidal effect on P. aeruginosa and S. aureus in comparison to P2 at their 2x MICs. Fluorescence microscopic studies suggested that peptides P2 and P4 both killed the bacteria via membrane disruption. Further, P4 exhibited lowest haemolytic activity among active peptides and negligible cytotoxic activity against human cancer cell lines A-549, PC-3 and HCT-116 at its MIC.
Assuntos
Aminoácidos/química , Anti-Infecciosos/química , Oligopeptídeos/química , Células A549 , Aminas/química , Anti-Infecciosos/farmacologia , Ácidos Cicloexanocarboxílicos/química , Gabapentina , Células HCT116 , Humanos , Lisina/química , Testes de Sensibilidade Microbiana , Oligopeptídeos/farmacologia , Estabilidade Proteica , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Fatores de Tempo , Ácido gama-Aminobutírico/químicaRESUMO
Melanin and related polydopamine hold great promise; however, restricted fine-tunabilility limits their usefulness in biocompatible applications. In the present study, by taking a biomimetic approach, we synthesize peptide-derived melanin with a range of physicochemical properties. Characterization of these melanin polymers indicates that they exist as nanorange materials with distinct size distribution, shapes, and surface charges. These variants demonstrate similar absorption spectra but have different optical properties that correlate with particle size. Our approach enables incorporation of chemical groups to create functionalized polyvalent organic nanomaterials and enables customization of melanin. Further, we establish that these synthetic variants are efficiently taken up by the skin keratinocytes, display appreciable photoprotection with minimal cytotoxicity, and thereby function as effective color matched photoprotective agents. In effect we demonstrate that an array of functionalized melanins with distinct properties could be synthesized using bioinspired green chemistry, and these are of immense utility in generating customized melanin/polydopamine like materials.
Assuntos
Queratinócitos/metabolismo , Melaninas/química , Melaninas/fisiologia , Lesões por Radiação/prevenção & controle , Dermatopatias/prevenção & controle , Pele/metabolismo , Biomimética , Células Cultivadas , Cor , Humanos , Indóis/química , Queratinócitos/citologia , Queratinócitos/efeitos da radiação , Polímeros/química , Proteção Radiológica , Pele/efeitos da radiação , Raios Ultravioleta/efeitos adversosRESUMO
The present work describes the anti-invasive effect of conjugate BC06, a novel conjugate of EPA, (2E,4E)-4-(benzo[d][1,3]dioxol-5-ylmethylene) hex-2-enoic acid with ß,ß-disubstituted-ß-amino acid, ß(3,3)-Pip-OH (2-(4-aminopiperidin-4-yl)acetic acid), in human pancreatic carcinoma. The conjugate BC06 inhibited invasion and migration of PANC-1 cells in wound healing, matrigel invasion, and gelatin degradation assays. Apart from suppressing PI3K/Akt/NF-kB signaling, which is involved in the up-regulation of matrix metalloproteinases, our study also demonstrated that dose-dependent treatment of BC06 results in the upregulation of TIMP-1 and E-cadherin expression. Further, BC06 was found to be inhibiting the metastatic ability of PANC-1 cells by reducing MMP-2 and MMP-9 expression. These findings suggest that EPA conjugate with ß(3,3)-Pip-OH, BC06, may be used as an anti-invasive agent against human pancreatic carcinoma.