RESUMO
Modern adjuvants for vaccine formulations are immunostimulating agents whose action is based on the activation of pattern recognition receptors (PRRs) by well-defined ligands to boost innate and adaptive immune responses. Monophosphoryl lipid A (MPLA), a detoxified analogue of lipid A, is a clinically approved adjuvant that stimulates toll-like receptor 4 (TLR4). The synthesis of MPLA poses manufacturing and quality assessment challenges. Bridging this gap, we report here the development and preclinical testing of chemically simplified TLR4 agonists that could sustainably be produced in high purity and on a large scale. Underpinned by computational and biological experiments, we show that synthetic monosaccharide-based molecules (FP compounds) bind to the TLR4/MD-2 dimer with submicromolar affinities stabilizing the active receptor conformation. This results in the activation of MyD88- and TRIF-dependent TLR4 signaling and the NLRP3 inflammasome. FP compounds lack in vivo toxicity and exhibit adjuvant activity by stimulating antibody responses with a potency comparable to MPLA.
Assuntos
Adjuvantes Imunológicos/farmacologia , Glucosamina/farmacologia , Glicolipídeos/farmacologia , Receptor 4 Toll-Like/antagonistas & inibidores , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Adjuvantes Imunológicos/síntese química , Adjuvantes Imunológicos/metabolismo , Adjuvantes Imunológicos/toxicidade , Animais , Feminino , Glucosamina/síntese química , Glucosamina/metabolismo , Glucosamina/toxicidade , Glicolipídeos/síntese química , Glicolipídeos/metabolismo , Glicolipídeos/toxicidade , Humanos , Inflamassomos/metabolismo , Interleucina-1/metabolismo , Macrófagos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Fator 88 de Diferenciação Mieloide/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismoRESUMO
Anemarrhena asphodeloides Bunge is a traditional Chinese medicine. The timosaponin BII is one of the most abundant and widely studied active ingredients in Anemarrhena asphodeloides Bunge. Related studies have shown that timosaponin BII has potential value for development and further utilization. The protective effect of timosaponin BII on islet ß cells under type 2 diabetes was investigated in the glycolipid toxic INS-1â cell model and possible biomarkers were explored by lipidomics analysis. Timosaponin BII was isolated from Anemarrhena asphodeloides Bunge by polyamide resin and Sephadex LH-20. Then, the glycolipid toxicity INS-1â cell model was established to investigate the protective effect of timosaponin BII. The results showed that timosaponin BII could significantly influence the levels of malondialdehyde (MDA) and glutathione (GSH), thereby restoring the insulin secretion ability and cell viability of model cells. Lipidomics analysis was combined with multivariate statistical analysis for marker selection. The four most common pathological and pharmacological lipid markers were phosphatidylserine (PS), suggesting that timosaponin BII had protective effects on model cells related to the reduction oxidative stress and macrophage inflammation. RAW264.7 macrophages were stimulated by LPS to establish a model of inflammation and study the effect of timosaponin BII on the nodes of NOD-like receptor P3 (NLRP3) inflammasome pathway in the model cells. In conclusion, timosaponin BII may have the effect of protecting INS-1 pancreatic ß cells through reducing IL-1ß (interleukin-1ß) production by inhibiting the NLRP3 inflammasome in macrophage and restoring the insulin secretion ability and cell viability by reducing oxidative stress.
Assuntos
Anemarrhena/química , Glicolipídeos/toxicidade , Substâncias Protetoras/química , Saponinas/química , Esteroides/química , Anemarrhena/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Análise Discriminante , Glutationa/metabolismo , Inflamação/metabolismo , Inflamação/patologia , Inflamação/prevenção & controle , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Interleucina-1beta/metabolismo , Lipidômica/métodos , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Malondialdeído/metabolismo , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Análise de Componente Principal , Substâncias Protetoras/farmacologia , Substâncias Protetoras/uso terapêutico , Células RAW 264.7 , Saponinas/isolamento & purificação , Saponinas/farmacologia , Saponinas/uso terapêutico , Esteroides/isolamento & purificação , Esteroides/farmacologia , Esteroides/uso terapêuticoRESUMO
Previously undescribed 1,2-O-diacyl-3-O-beta-D-galactopyranosyl glycerols and 1,2-O-diacyl-3-O-[alpha-D-galactopyranosyl-(1"-->6')-O-beta-D- galactopyranosyl] glycerols were isolated as single components from Arisaema amurense. The cytotoxicities of these compounds against P388 and DLD-1 are described.
Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Glicolipídeos/isolamento & purificação , Plantas Medicinais , Plantas Tóxicas , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/toxicidade , Configuração de Carboidratos , Sequência de Carboidratos , Sobrevivência Celular/efeitos dos fármacos , Glicolipídeos/química , Glicolipídeos/toxicidade , Leucemia P388 , Espectroscopia de Ressonância Magnética , Camundongos , Dados de Sequência Molecular , Células Tumorais CultivadasAssuntos
Antibacterianos , Glicolipídeos , Animais , Antibacterianos/análise , Antibacterianos/sangue , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antibacterianos/toxicidade , Antibacterianos/urina , Glicolipídeos/sangue , Glicolipídeos/farmacologia , Glicolipídeos/uso terapêutico , Glicolipídeos/toxicidade , Glicolipídeos/urina , Masculino , Camundongos , Testes de Sensibilidade Microbiana , Neisseria/efeitos dos fármacos , Fósforo/análise , Infecções Pneumocócicas/tratamento farmacológico , Ligação Proteica , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus/efeitos dos fármacos , Streptococcus/efeitos dos fármacos , Streptomyces/análiseRESUMO
The toxicity for mice of the cord factor of Cornebacterium diphtheriae, trehalose-6,6'-dicorynomycolate, was studied. The diphtherial cord factor showed a delayed lethal toxicity for mice; the median lethal dose was 120 mug. Mouse liver mitochondria were disrupted in vivo under the toxic action of the diphtherial cord factor into fragments deficient in both respiration and phosphorylation. The site of metabolic defect in the mitochondrial electron transport system was located at the region prior to the level of cytochrome c in the livers of cord factor-intoxicated mice. These effects of the diphtherial cord factor on the host-cell mitochondria were essentially similar to those of the cord factor of Mycobacterium tuberculosis, trehalose-6,6'-dimycolate.