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1.
Mar Drugs ; 20(2)2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35200660

RESUMO

Human noroviruses are the most common pathogens causing acute gastroenteritis and may lead to more severe illnesses among immunosuppressed people, including elderly and organ transplant recipients. To date, there are no safe and effective vaccines or antiviral agents for norovirus infections. In the present study, we aimed to demonstrate the antiviral activity of monogalactosyl diacylglyceride (MGDG) isolated from a microalga, Coccomyxa sp. KJ, against murine norovirus (MNV) and feline calicivirus (FCV), the surrogates for human norovirus. MGDG showed virucidal activities against these viruses in a dose- and time-dependent manner-MGDG at 100 µg/mL reduced the infectivity of MNV and FCV to approximately 10% after 60 min incubation. In the animal experiments of MNV infection, intraoral administration of MGDG (1 mg/day) exerted a therapeutic effect by suppressing viral shedding in the feces and produced high neutralizing antibody titers in sera and feces. When MGDG was orally administered to immunocompromised mice treated with 5-fluorouracil, the compound exhibited earlier stopping of viral shedding and higher neutralizing antibody titers of sera than those in the control mice administered with distilled water. Thus, MGDG may offer a new therapeutic and prophylactic alternative against norovirus infections.


Assuntos
Antivirais/farmacologia , Infecções por Caliciviridae/tratamento farmacológico , Galactolipídeos/farmacologia , Microalgas/metabolismo , Animais , Anticorpos Neutralizantes/sangue , Antivirais/administração & dosagem , Antivirais/isolamento & purificação , Infecções por Caliciviridae/virologia , Calicivirus Felino/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Galactolipídeos/administração & dosagem , Galactolipídeos/isolamento & purificação , Camundongos , Camundongos Endogâmicos BALB C , Norovirus/efeitos dos fármacos , Fatores de Tempo , Eliminação de Partículas Virais/efeitos dos fármacos
2.
J Am Chem Soc ; 144(6): 2474-2478, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-35129341

RESUMO

The human immune system detects potentially pathogenic microbes with receptors that respond to microbial metabolites. While the overall immune signaling pathway is known in considerable detail, the initial molecular signals, the microbially produced immunogens, for important diseases like Lyme disease (LD) are often not well-defined. The immunogens for LD are produced by the spirochete Borrelia burgdorferi, and a galactoglycerolipid (1) has been identified as a key trigger for the inflammatory immune response that characterizes LD. This report corrects the original structural assignment of 1 to 3, a change of an α-galactopyranose to an α-galactofuranose headgroup. The seemingly small change has important implications for the diagnosis, prevention, and treatment of LD.


Assuntos
Antígenos de Bactérias/química , Borrelia burgdorferi/química , Galactolipídeos/química , Animais , Antígenos de Bactérias/farmacologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Galactolipídeos/síntese química , Galactolipídeos/farmacologia , Inflamação/induzido quimicamente , Doença de Lyme/imunologia , Camundongos , Receptor 2 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
3.
PLoS One ; 14(7): e0219305, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31310628

RESUMO

A monogalactosyl diacylglyceride (MGDG) was isolated as an antiviral component from Coccomyxa sp. KJ (IPOD FERM BP-22254) via bioassay-guided fractionation. α-Linolenic acid (C18:3) and 7,10,13-hexadecatrienoic acid (C16:3) accounted for approximately 72% and 23%, respectively, of the MGDG total fatty acids of the MGDG. The MGDG showed virucidal activity against herpes simplex virus type 2 (HSV-2), a pathogen that causes genital herpes. Physical changes in HSV-2 shape were observed after treatment with MGDG, including a decrease in particle size, and possible damage to the viral envelope, as assessed using electron microscopy. In accordance with the morphological findings, virus particles lost their ability to bind to host cells. HSV-2 treated with high concentrations of MGDG resulted in no pathogenicity in an animal model, indicating that MGDG exhibits irreversible virucidal activity against HSV-2 particles. In the animal model of HSV-2-induced genital herpes, intravaginally administered MGDG exerted a prophylactic effect by suppressing viral yields in the genital cavity and formation of herpetic lesions, resulting in a higher survival rate in treated mice than control mice administered solvent. Thus, MGDG offers a novel prophylactic option against HSV infections.


Assuntos
Antivirais/farmacologia , Galactolipídeos/farmacologia , Herpes Genital/terapia , Herpesvirus Humano 2/efeitos dos fármacos , Microalgas/química , Administração Intravaginal , Animais , Antivirais/análise , Chlorocebus aethiops , Modelos Animais de Doenças , Ácidos Graxos Insaturados/análise , Feminino , Galactolipídeos/análise , Herpes Genital/virologia , Camundongos , Camundongos Endogâmicos BALB C , Tamanho da Partícula , Células Vero , Ácido alfa-Linolênico/análise
4.
Int J Mol Sci ; 18(9)2017 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-28869526

RESUMO

The HA1 subunit of the influenza virus hemagglutinin (HA) is a valuable antigen for the development of vaccines against flu due to the availability of most antigenic sites which are conformational. Therefore, a novel adjuvanted antigen delivery system, tubular immunostimulating complexes (TI-complexes) comprising monogalactosyldiacylglycerol (MGDG) from different marine macrophytes as a lipid matrix for an antigen, was applied to enhance the immunogenicity of recombinant HA1 of influenza A H1N1 and to study the relation between its immunogenicity and conformation. The content of anti-HA1 antibodies and cytokines was estimated by ELISA after the immunization of mice with HA1 alone, and HA1 was incorporated in TI-complexes based on different MGDGs isolated from green algae Ulva lactuca, brown algae Sargassum pallidum, and seagrass Zostera marina. Conformational changes of HA1 were estimated by differential scanning calorimetry and intrinsic fluorescence. It was shown that the adjuvant activity of TI-complexes depends on the microviscosity of MGDGs, which differently influence the conformation of HA1. The highest production of anti-HA1 antibodies (compared with the control) was induced by HA1 incorporated in a TI-complex based on MGDG from S. pallidum, which provided the relaxation of the spatial structure and, likely, the proper presentation of the antigen to immunocompetent cells.


Assuntos
Antígenos Virais/química , Antígenos Virais/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Adjuvantes Imunológicos/química , Animais , Anticorpos Antivirais/imunologia , Varredura Diferencial de Calorimetria , Citocinas/metabolismo , Galactolipídeos/química , Galactolipídeos/farmacologia , Vacinas contra Influenza/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Conformação Proteica/efeitos dos fármacos , Desnaturação Proteica
5.
Exp Neurol ; 289: 64-72, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28013000

RESUMO

Status epilepticus (SE) in rats, along with chronic epilepsy, leads to the development of behavioral impairments resembling depressive disorder and/or attention deficit/hyperactivity disorder (ADHD), thus reflecting respective comorbidities in epilepsy patients. Suppressed neurotransmitter tone in the raphe nucleus (RN)-prefrontal cortex (PFC) serotonergic pathway and in the locus coeruleus (LC)-PFC noradrenergic pathway underlies depressive- and impulsive-like behavioral deficits respectively. We examined possible mechanisms leading to the monoamine dysfunction in brainstem efferents, namely modulatory effects of the neuropeptide galanin on serotonin (5-HT) and norepinephrine (NE) signaling. SE was induced in young adult male Wistar rats by LiCl and pilocarpine. Epileptic rats were categorized vis-à-vis behavioral deficits as not impaired, "depressed" and "impulsive". Depressive- and impulsive-like behaviors were examined in the forced swimming test (FST). The strength of serotonergic transmission in RN-PFC and of noradrenergic transmission in LC-PFC was analyzed using in vivo fast scan cyclic voltammetry. Galanin receptor type 1 (GalR1)/type 2 (GalR2) antagonist M40, and a preferential GalR2 antagonist M871 were administered over 3days locally into either RN or LC by means of ALZET osmotic minipumps connected to locally implanted infusion cannulas. Intra-RN injection of M40 improved serotonergic tone and depressive-like behavior in epileptic "depressed" rats. Intra-LC injection of M40 improved noradrenergic tone and impulsive-like behavior in epileptic "impulsive" rats. The effects of M40 were only observed in impaired subjects. The treatment did not modify neurotransmission and behavior in naïve and epileptic not impaired rats; in "depressed" rats the effects were limited to serotonergic transmission and immobility, while in "impulsive" rats - to noradrenergic transmission and struggling behavior. Intra-RN administration of M871 exacerbated depressive-like behavior, but had no effects on any other of the examined parameters in any category of animals. These findings suggest that endogenous galanin, acting through GalR1 may be involved in the pathophysiology of epilepsy-associated depression and ADHD via inhibiting RN-PFC serotonergic and LC-PFC noradrenergic transmissions respectively.


Assuntos
Monoaminas Biogênicas/metabolismo , Depressão , Galanina/metabolismo , Locus Cerúleo/patologia , Núcleos da Rafe/patologia , Estado Epiléptico/complicações , Animais , Antidepressivos/farmacologia , Depressão/etiologia , Depressão/metabolismo , Depressão/patologia , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos , Galactolipídeos/farmacologia , Galanina/antagonistas & inibidores , Galanina/farmacologia , Comportamento Impulsivo/efeitos dos fármacos , Comportamento Impulsivo/fisiologia , Cloreto de Lítio/uso terapêutico , Locus Cerúleo/diagnóstico por imagem , Masculino , Agonistas Muscarínicos/toxicidade , Fragmentos de Peptídeos/farmacologia , Pilocarpina/toxicidade , Núcleos da Rafe/efeitos dos fármacos , Ratos , Ratos Wistar , Serotonina/metabolismo , Estado Epiléptico/induzido quimicamente , Natação/psicologia
6.
Radiat Oncol ; 11(1): 153, 2016 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-27876069

RESUMO

BACKGROUND: In our previous study, monogalactosyl diacylglycerol (MGDG) purified from spinach was found to have cytotoxic effects in human cancer cell lines. This study further assessed whether MGDG can enhance the cytotoxic effects of radiation in human pancreatic cancer cells in vitro and in vivo. METHODS: Glycoglycerolipids from spinach including MGDG were extracted from dried spinach. The cytotoxicity of MGDG were evaluated by the MTT assay using four human pancreatic cancer cell lines (MIAPaCa-2, AsPC-1, BxPC-3 and PANC-1) and normal human dermal fibroblasts (NHDFs). The effects of radiation and MGDG alone or in combination in MIAPaCa-2 cells was analyzed with the colony forming and apoptosis assays, western blotting and cell cycle and DNA damage analyses (γ-H2AX foci staining and comet assay). The inhibitory effects on tumor growth were assessed in a mouse xenograft tumor model. RESULTS: MGDG showed dose- and time-dependent cytotoxicity, with half-maximal inhibitory concentrations (IC50) in PANC-1, BxPC-3, MIAPaCa-2 and AsPC-1 cells at 72 h of 25.6 ± 2.5, 26.9 ± 1.3, 18.5 ± 1.7, and 22.7 ± 1.9 µM, respectively. The colony forming assay revealed fewer MIAPaCa-2, BxPC-3 and AsPC-1 cell colonies upon treatment with both MGDG and radiation as compared to irradiation alone (P < 0.05). The combination of MGDG and radiation induced a higher proportion of apoptosis in MIAPaCa-2 cells; this effect was associated with increased mitochondrial release of cytochrome c and activation of cleaved poly (ADP-ribose) polymerase and caspase-3. DNA damage was detected and DNA repair mechanisms were more frequently impaired in cells receiving the combination treatment as compared to either one alone. Tumor growth was inhibited to a greater degree in mice treated by intratumoral injection of MGDG combined with irradiation as compared to either one alone (P < 0.05). CONCLUSIONS: This is the first report demonstrating that MGDG enhances the cytotoxicity of radiation to induce apoptosis of cancer cells in vitro and in vivo. Our findings indicate that this therapeutic combination can be an effective strategy for the treatment of pancreatic cancer.


Assuntos
Quimiorradioterapia/métodos , Galactolipídeos/farmacologia , Neoplasias Pancreáticas/patologia , Extratos Vegetais/farmacologia , Radiossensibilizantes/farmacologia , Spinacia oleracea , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Western Blotting , Linhagem Celular Tumoral , Ensaio Cometa , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/efeitos da radiação , Reparo do DNA/efeitos dos fármacos , Reparo do DNA/efeitos da radiação , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Angew Chem Int Ed Engl ; 55(46): 14330-14334, 2016 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-27762087

RESUMO

Glycolipids are important structural components of biological membranes and perform crucial functions in living systems, including signaling transduction and interaction with extracellular environment. However, the mechanistic exploration of glycolipids in vivo is challenging because they are not genetically encoded. Herein, we designed and synthesized a series of bifunctional monogalactosyldiacylglycerol (MGDG) probes as a model by introducing diazirine and terminal alkyne moieties on an aliphatic chain. In combination with proteome profiling and molecular modeling, we have demonstrated that MGDG alleviates inflammation by antagonizing TLR4.


Assuntos
Galactolipídeos/química , Glicolipídeos/química , Proteínas/química , Alcinos/química , Condrócitos/citologia , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Química Click , Diazometano/química , Eletroforese em Gel de Poliacrilamida , Galactolipídeos/farmacologia , Humanos , Antígeno 96 de Linfócito/química , Antígeno 96 de Linfócito/metabolismo , Espectrometria de Massas , Proteínas/metabolismo , Receptor 4 Toll-Like/química , Receptor 4 Toll-Like/metabolismo , Raios Ultravioleta
8.
J Agric Food Chem ; 64(46): 8783-8794, 2016 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-27786470

RESUMO

Isochrysis galbana is a marine microalga rich in PUFAs that is widely used as feed in aquaculture and more recently investigated for its potential in food applications and as source of bioactive compounds. In this study, the biomass obtained from cultures of I. galbana has been investigated to determine its content in glycosylglycerides and glycosylceramides. By using NMR, UPLC-MS/MS, and fatty acid profiles, the structures of ten monogalactosyldiacylglycerols (MGDGs 1-10) and nine digalactosyldiacylglycerols (DGDGs 11-19) have been established. Two distinctive features of the galactosylglycerides from I. galbana are the wide presence of highly unsaturated acyl chains derived from stearidonic acid (18:4Δ6Z,9Z,12Z,15Z) and octadecapentaenoic acid (18:5Δ3Z,6Z,9Z,12Z,15Z), as well as the unusual coexistence of αß-DGDGs and ßß-DGDGs. Three new galactosylceramides, isogalbamides A-C (20-22), have also been isolated and characterized by NMR and MS/MS. These metabolites, which are the first galactosylceramides described from microalgae, derive from unprecedented tetraolefinic sphingoid bases. In anti-inflammatory assays, the MGDG and DGDG mixtures and the isolated DGDGs 11 and 12 showed significant activity as inhibitors of the production of the pro-inflammatory cytokine TNF-α in lipopolysaccharide-stimulated human THP-1 macrophages, while the galactosylceramides showed moderated activity.


Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Galactolipídeos/química , Galactolipídeos/farmacologia , Galactosilceramidas/farmacologia , Haptófitas/química , Microalgas/química , Anti-Inflamatórios/isolamento & purificação , Galactolipídeos/isolamento & purificação , Galactosilceramidas/isolamento & purificação , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Estrutura Molecular , Espectrometria de Massas em Tandem , Fator de Necrose Tumoral alfa/imunologia
9.
Nat Prod Res ; 30(10): 1219-23, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26181315

RESUMO

The in vitro anti-denaturation and anti-hyaluronidase activities of Impatiens parviflora extracts and isolated galactolipids (MGDG-1, DGDG-1) were investigated. This is the first report on these compounds in I. parviflora. All extracts showed anti-hyaluronidase activity, but only methanolic extract from fresh leaves exhibited significant activity against heat-induced denaturation of BSA in a dose-dependent manner. At 500 µg/mL, the extract and the reference drug showed 79.05% and 99.81% inhibition of protein denaturation, respectively. These results indicate that fresh leaves of I. parviflora may be beneficial in inflammatory conditions, especially those associated with protein denaturation, such as rheumatoid arthritis. The study revealed that only MGDG-1 showed weak activity in anti-denaturation assay but both galactolipids were potent inhibitors of hyaluronidase. MGDG-1 completely inhibited the enzyme activity at the concentration of 127.9 µg/mL. These results indicate the potential of galactolipids in the treatment of diseases associated with the loss of hyaluronic acid.


Assuntos
Anti-Inflamatórios/farmacologia , Galactolipídeos/farmacologia , Hialuronoglucosaminidase/antagonistas & inibidores , Impatiens/química , Extratos Vegetais/química , Anti-Inflamatórios/isolamento & purificação , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Galactolipídeos/isolamento & purificação , Folhas de Planta/química
10.
Carbohydr Res ; 408: 114-8, 2015 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-25683967

RESUMO

This study describes an interesting observation that the mixture of anomeric galactolipids has synergistic effects on the growth inhibition of human multiple myeloma (MM) cells. We determine that the equivalent mixture of a pair of α- and ß-galactolipids with a 14-carbon lipid chain can cause stronger poly ADP-ribose polymerase cleavage and DNA damage, producing more late apoptotic MM cells, than either anomer alone.


Assuntos
Dano ao DNA , Galactolipídeos/química , Galactolipídeos/farmacologia , Mieloma Múltiplo/genética , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Humanos , Poli(ADP-Ribose) Polimerases/metabolismo
11.
J Agric Food Chem ; 62(46): 11157-62, 2014 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-25363514

RESUMO

The chemical composition of monogalactosyldiacylglycerols (MGDGs) from brown alga Sargassum horneri and their inhibitory effects on lipid accumulation were investigated in this study. A total of 10 molecular species of MGDGs were identified using nuclear magnetic resonance, alkaline hydrolysis, gas chromatography-flame ionization detector, and high-performance liquid chromatography-tandem mass spectrometry methods. Individual molecular species of MGDGs, including (2S)-1-O-myristoyl-2-O-palmitoleoyl-3-O-ß-D-galactopyranosyl-sn-glycerol (1), (2S)-1-O-myristoyl-2-O-linoleyl-3-O-ß-D-galactopyranosyl-sn-glycerol (3), (2S)-1-O-palmitoyl-2-O-linolenoyl-3-O-ß-D-galactopyranosyl-sn-glycerol (5), (2S)-1-O-myristoyl-2-O-oleyl-3-O-ß-D-galactopyranosyl-sn-glycerol (7), (2S)-1-O-palmitoyl-2-O-palmitoleoyl-3-O-ß-D-galactopyranosyl-sn-glycerol (8), (2S)-1-O-palmitoyl-2-O-linoleyl-3-O-ß-D-galactopyranosyl-sn-glycerol (9), and (2S)-1-O-palmitoyl-2-O-oleyl-3-O-ß-D-galactopyranosyl-sn-glycerol (10), were then furnished using semi-preparative high-performance liquid chromatography, and their inhibitory effects on triglyceride (TG) accumulation and free fatty acid (FFA) levels in 3T3-L1 adipocytes were evaluated. Compounds 3 and 9 showed inhibitory effects on TG and FFA accumulation, with TG levels of 1.568 ± 0.2808 and 1.701 ± 0.1460 µmol/L and FFA levels of 0.149 ± 0.0258 and 0.198 ± 0.0229 mequiv/L, respectively, which were more effective than other compounds. The primary structure-activity relationship suggested that linoleyl [18:2(ω-6)] in the sn-2 position played an important role on triglyceride accumulation inhibition.


Assuntos
Adipócitos/efeitos dos fármacos , Galactolipídeos/farmacologia , Extratos Vegetais/farmacologia , Sargassum/química , Alga Marinha/química , Triglicerídeos/metabolismo , Células 3T3 , Adipócitos/metabolismo , Animais , Galactolipídeos/química , Galactolipídeos/isolamento & purificação , Espectrometria de Massas , Camundongos , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Relação Estrutura-Atividade , Verduras/química
12.
Biochem Biophys Res Commun ; 452(3): 347-53, 2014 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-25152404

RESUMO

The three cloned galanin receptors show a higher affinity for galanin than for galanin N-terminal fragments. Galanin fragment (1-15) binding sites were discovered in the rat Central Nervous System, especially in dorsal hippocampus, indicating a relevant role of galanin fragments in central galanin communication. The hypothesis was introduced that these N-terminal galanin fragment preferring sites are formed through the formation of GalR1-GalR2 heteromers which may play a significant role in mediating galanin fragment (1-15) signaling. In HEK293T cells evidence for the existence of GalR1-GalR2 heteroreceptor complexes were obtained with proximity ligation and BRET(2) assays. PLA positive blobs representing GalR1-GalR2 heteroreceptor complexes were also observed in the raphe-hippocampal system. In CRE luciferase reporter gene assays, galanin (1-15) was more potent than galanin (1-29) in inhibiting the forskolin-induced increase of luciferase activity in GalR1-GalR2 transfected cells. The inhibition of CREB by 50nM of galanin (1-15) and of galanin (1-29) was fully counteracted by the non-selective galanin antagonist M35 and the selective GalR2 antagonist M871. These results suggested that the orthosteric agonist binding site of GalR1 protomer may have an increased affinity for the galanin (1-15) vs galanin (1-29) which can lead to its demonstrated increase in potency to inhibit CREB vs galanin (1-29). In contrast, in NFAT reporter gene assays galanin (1-29) shows a higher efficacy than galanin (1-15) in increasing Gq/11 mediated signaling over the GalR2 of these heteroreceptor complexes. This disbalance in the signaling of the GalR1-GalR2 heteroreceptor complexes induced by galanin (1-15) may contribute to depression-like actions since GalR1 agonists produce such effects.


Assuntos
Galanina/farmacologia , Hipocampo/metabolismo , Neurônios/metabolismo , Fragmentos de Peptídeos/farmacologia , Receptor Tipo 1 de Galanina/metabolismo , Receptor Tipo 2 de Galanina/metabolismo , Regulação Alostérica , Animais , Bradicinina/análogos & derivados , Bradicinina/farmacologia , Mapeamento Encefálico , Proteína de Ligação a CREB/antagonistas & inibidores , Proteína de Ligação a CREB/genética , Proteína de Ligação a CREB/metabolismo , Galactolipídeos/farmacologia , Galanina/metabolismo , Regulação da Expressão Gênica , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Humanos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Fragmentos de Peptídeos/metabolismo , Regiões Promotoras Genéticas , Multimerização Proteica , Ratos , Receptor Tipo 1 de Galanina/agonistas , Receptor Tipo 1 de Galanina/química , Receptor Tipo 1 de Galanina/genética , Receptor Tipo 2 de Galanina/química , Receptor Tipo 2 de Galanina/genética , Transdução de Sinais
13.
J Nat Med ; 68(1): 31-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23508568

RESUMO

The genus Ophioglossum consists of ferns with different therapeutic properties, including vulnerary virtues. The species Ophioglossum vulgatum L. is traditionally used on wounds and burns as an ointment, suggesting the occurrence of lipophilic compounds with tissue repair properties. We isolated and characterized a galactosyldiacylglycerol mixture (1), composed mainly of 1,2-di-O-linolenoyl-3-O-ß-D-galactopyranosyl-glycerol, from the frond dichloromethane extract. The wound healing properties of 1 were assessed in vitro on keratinocytes. Scratch wound assays showed increased wound closure rates in keratinocyte monolayers exposed to subtoxic doses, previously determined in cytotoxicity assays. The strongest effect, obtained at a dose of 5 µg/mL, approached that of a platelet lysate used in clinical settings. The use of inhibitors of the main cellular pathways involved in wound repair, revealed important roles for intracellular calcium and the ERK1/2 MAP kinase. Conversely, a PCR array of genes involved in wound healing showed an almost total absence of gene modulation. Taken together, the data suggest that 1 acts through a Ca(2+)-dependent, nongenomic mechanism involving the activation of ERK1/2 MAP kinase. Hence, 1 is a main candidate to explain the wound healing virtues of O. vulgatum ointment, and is proposed as a possible new drug in tissue repair and regenerative medicine.


Assuntos
Gleiquênias , Galactolipídeos/farmacologia , Queratinócitos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Cicatrização/efeitos dos fármacos , Sinalização do Cálcio/efeitos dos fármacos , Linhagem Celular , Relação Dose-Resposta a Droga , Gleiquênias/química , Galactolipídeos/isolamento & purificação , Humanos , Queratinócitos/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/farmacologia , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/farmacologia , Fitoterapia , Extratos Vegetais/isolamento & purificação , Folhas de Planta , Plantas Medicinais
14.
Carbohydr Res ; 376: 15-23, 2013 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-23727703

RESUMO

Aminoglycoglycerolipid 1a isolated from an algal extract showed activity against the enzyme Myt1 kinase with an IC50 value of 0.12 µg/mL. Its analogues, 6'-acylamido-6'-deoxy-α-D-galactoglycerolipids (2a-g) were synthesized in an efficient way with high stereoselectivity. The key step was to employ a 4-OAc protecting group of the galactosyl donor 14 as a remote neighboring participation group to give the glycoside with high α-anomeric selectivity (α:ß=32:1) in the glycosylation. The preliminary bioactivity screening showed that compound 2g exhibited good inhibition against Myt1 kinase.


Assuntos
Galactolipídeos/síntese química , Inibidores de Proteínas Quinases/síntese química , Configuração de Carboidratos , Galactolipídeos/química , Galactolipídeos/farmacologia , Humanos , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/metabolismo , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Relação Estrutura-Atividade
15.
Nat Prod Res ; 27(12): 1084-90, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22973805

RESUMO

Methanolic extracts of some marine and freshwater microalgae were tested for their nitric oxide (NO) inhibitory activity on lipopolysaccharide-induced NO production in RAW264.7 macrophage cells. Among the tested extracts, Tetraselmis chui extract showed the strongest NO inhibitory activity, thus selected for further study. NO inhibitory activity guided isolation led to identification of two monogalactosyldiacylglycerols (MGDGs) (2S)-1-O-(6Z,9Z,12Z,15Z-octadecatetranoyl)-2-O-(4Z,7Z,10Z,13Z-hexadecatetranoyl)-3-O-ß-D-galactopyranosylglycerol (1) and (2S)-1-O-(9Z,12Z,15Z-octadecatrinoyl)-2-O-(4Z,7Z,10Z,13Z-hexadecatetranoyl)-3-O-ß-D-galactopyranosylglycerol (2) from the MeOH extract of T. chui. The stereo-chemistry of 1 was elucidated by classical degradation method. MGDGs 1 and 2 showed strong NO inhibitory activity compared to N(G)-methyl-L-arginine acetate salt, a well known NO inhibitor used as a positive control. Isolated MGDGs suppressed NO production through down-regulation of inducible NO synthase protein. A structure activity relationship study suggested that the polyunsaturated fatty acids of the MGDGs are responsible for NO inhibition. Moreover, increasing unsaturation on the fatty acid side chains enhanced the NO inhibitory potency of the MGDGs.


Assuntos
Clorófitas/química , Galactolipídeos/química , Galactolipídeos/farmacologia , Macrófagos/efeitos dos fármacos , Óxido Nítrico/metabolismo , Animais , Arginina/análogos & derivados , Linhagem Celular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Ácidos Graxos Insaturados/química , Galactosídeos/química , Galactosídeos/farmacologia , Glicerol/análogos & derivados , Glicerol/química , Glicerol/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Camundongos , Microalgas/química , Estrutura Molecular , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Relação Estrutura-Atividade
16.
Biochim Biophys Acta ; 1830(3): 2517-25, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23174220

RESUMO

BACKGROUND: Gemcitabine (GEM) is used to treat various carcinomas and represents an advance in pancreatic cancer treatment. In the screening for DNA polymerase (pol) inhibitors, a glycoglycerolipid, monogalactosyl diacylglycerol (MGDG), was isolated from spinach. METHODS: Phosphorylated GEM derivatives were chemically synthesized. In vitro pol assay was performed according to our established methods. Cell viability was measured using MTT assay. RESULTS: Phosphorylated GEMs inhibition of mammalian pol activities assessed, with the order of their effect ranked as: GEM-5'-triphosphate (GEM-TP) > GEM-5'-diphosphate > GEM-5'-monophosphate > GEM. GEM suppressed growth in the human pancreatic cancer cell lines BxPC-3, MIAPaCa2 and PANC-1 although phospholylated GEMs showed no effect MGDG suppressed growth in these cell lines based on its selective inhibition of replicative pol species. Kinetic analysis showed that GEM-TP was a competitive inhibitor of pol alpha activity with nucleotide substrates, and MGDG was a noncompetitive inhibitor with nucleotide substrates. GEM combined with MGDG treatments revealed synergistic effects on the inhibition of DNA replicative pols alpha and gamma activities compared with GEM or MGDG alone. In cell growth suppression by GEM, pre-addition of MGDG significantly enhanced cell proliferation suppression, and the combination of these compounds was found to induce apoptosis. In contrast, GEM-treated cells followed by MGDG addition did not influence cell growth. CONCLUSIONS: GEM/MGDG enhanced the growth suppression of cells based on the inhibition of pol activities. GENERAL SIGNIFICANCE: Spinach MGDG has great potential for development as an anticancer food compound and could be an effective clinical anticancer chemotherapy in combination with GEM.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Inibidores Enzimáticos/farmacologia , Galactolipídeos/farmacologia , Proteínas de Neoplasias/antagonistas & inibidores , Inibidores da Síntese de Ácido Nucleico , Spinacia oleracea/química , Animais , Antimetabólitos Antineoplásicos/química , Antimetabólitos Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma/tratamento farmacológico , Carcinoma/metabolismo , Carcinoma/patologia , Bovinos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , DNA Polimerase Dirigida por DNA/metabolismo , Desoxicitidina/análogos & derivados , Desoxicitidina/química , Desoxicitidina/farmacologia , Sinergismo Farmacológico , Inibidores Enzimáticos/isolamento & purificação , Galactolipídeos/isolamento & purificação , Humanos , Isoenzimas/antagonistas & inibidores , Isoenzimas/metabolismo , Cinética , Proteínas de Neoplasias/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Extratos Vegetais/química , Ratos , Gencitabina
17.
Mar Drugs ; 10(4): 918-931, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22690151

RESUMO

Glycolipids were extracted from the red alga Osmundaria obtusiloba from Southeastern Brazilian coast. The acetone insoluble material was extracted with chloroform/methanol and the lipids, enriched in glycolipids, were fractionated on a silica gel column eluted with chloroform, acetone and then methanol. Three major orcinol-positive bands were found in the acetone and methanol fractions, being detected by thin layer chromatography. The structures of the corresponding glycolipids were elucidated by ESI-MS and (1)H/(13)C NMR analysis, on the basis of their tandem-MS behavior and HSQC, TOCSY fingerprints. For the first time, the structure of sulfoquinovosyldiacylglycerol from the red alga Osmundaria obtusiloba was characterized. This molecule exhibited potent antiviral activity against HSV-1 and HSV-2 with EC(50) values of 42 µg/mL to HSV-1 and 12 µg/mL to HSV-2, respectively. Two other glycolipids, mono- and digalactosyldiacylglycerol, were also found in the alga, being characterized by ESI-MS/MS. The structural elucidation of algae glycolipids is a first step for a better understanding of the relation between these structures and their biological activities.


Assuntos
Antivirais/química , Antivirais/farmacologia , Glicolipídeos/química , Glicolipídeos/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 2/efeitos dos fármacos , Rodófitas/química , Animais , Antivirais/isolamento & purificação , Brasil , Galactolipídeos/química , Galactolipídeos/isolamento & purificação , Galactolipídeos/farmacologia , Glicolipídeos/isolamento & purificação , Lipídeos/química , Lipídeos/isolamento & purificação , Lipídeos/farmacologia , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/métodos , Células Vero
18.
Biochim Biophys Acta ; 1823(5): 1033-40, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22425965

RESUMO

Recent studies demonstrated that lipids influence the assembly and efficiency of membrane-embedded macromolecular complexes. Similarly, lipids have been found to influence chloroplast precursor protein binding to the membrane surface and to be associated with the Translocon of the Outer membrane of Chloroplasts (TOC). We used a system based on chloroplast outer envelope vesicles from Pisum sativum to obtain an initial understanding of the influence of lipids on precursor protein translocation across the outer envelope. The ability of the model precursor proteins p(OE33)titin and pSSU to be recognized and translocated in this simplified system was investigated. We demonstrate that transport across the outer membrane can be observed in the absence of the inner envelope translocon. The translocation, however, was significantly slower than that observed for chloroplasts. Enrichment of outer envelope vesicles with different lipids natively found in chloroplast membranes altered the binding and transport behavior. Further, the results obtained using outer envelope vesicles were consistent with the results observed for the reconstituted isolated TOC complex. Based on both approaches we concluded that the lipids sulfoquinovosyldiacylglycerol (SQDG) and phosphatidylinositol (PI) increased TOC-mediated binding and import for both precursor proteins. In contrast, enrichment in digalactosyldiacylglycerol (DGDG) improved TOC-mediated binding for pSSU, but decreased import for both precursor proteins. Optimal import occurred only in a narrow concentration range of DGDG.


Assuntos
Proteínas de Cloroplastos/metabolismo , Cloroplastos/metabolismo , Membranas Intracelulares/metabolismo , Lipídeos/farmacologia , Precursores de Proteínas/metabolismo , Cloroplastos/efeitos dos fármacos , Corantes Fluorescentes/metabolismo , Galactolipídeos/farmacologia , Membranas Intracelulares/efeitos dos fármacos , Pisum sativum/metabolismo , Ligação Proteica/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Ribulose-Bifosfato Carboxilase/metabolismo , Lipossomas Unilamelares/metabolismo
19.
Bioorg Med Chem Lett ; 22(5): 2030-2, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22326167

RESUMO

The anomeric mixture of a series of O-galactolipid derivatives is revealed to be more toxic against several cancer cell lines than their either single component with the pure α- or ß-configuration. This interesting phenomenon has been confirmed on pairs of synthesized O-galactosyl anomers bearing length-varied alkyl chains at the lipid end. Furthermore, the most potent mixture was determined inoffensive to a normal cell line tested.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Galactolipídeos/química , Galactolipídeos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Humanos , Neoplasias/tratamento farmacológico
20.
Eur J Med Chem ; 50: 230-5, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22348826

RESUMO

Bioassay guided fractionation of ethanolic extract of the leaves of Bauhinia racemosa led to the isolation of galactolipid and catechin class of the compounds (1-7) from the most active n-butanol fraction (F4). Among the active galactolipids, 1 emerged as the lead molecule which was active on both forms of lymphatic filarial parasite, Brugia malayi. It was found to be better than the standard drug ivermectin and diethylcarbamazine (DEC) in terms of dose and efficacy.


Assuntos
Bauhinia/química , Brugia Malayi/efeitos dos fármacos , Filariose Linfática/tratamento farmacológico , Filaricidas/isolamento & purificação , Filaricidas/farmacologia , Galactolipídeos/isolamento & purificação , Galactolipídeos/farmacologia , Animais , Anti-Helmínticos/isolamento & purificação , Anti-Helmínticos/farmacologia , Dietilcarbamazina/uso terapêutico , Filariose Linfática/parasitologia , Humanos , Ivermectina/uso terapêutico , Extratos Vegetais/farmacologia , Folhas de Planta/química
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