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1.
Mar Drugs ; 20(2)2022 Feb 10.
Article in English | MEDLINE | ID: mdl-35200660

ABSTRACT

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.


Subject(s)
Antiviral Agents/pharmacology , Caliciviridae Infections/drug therapy , Galactolipids/pharmacology , Microalgae/metabolism , Animals , Antibodies, Neutralizing/blood , Antiviral Agents/administration & dosage , Antiviral Agents/isolation & purification , Caliciviridae Infections/virology , Calicivirus, Feline/drug effects , Disease Models, Animal , Dose-Response Relationship, Drug , Female , Galactolipids/administration & dosage , Galactolipids/isolation & purification , Mice , Mice, Inbred BALB C , Norovirus/drug effects , Time Factors , Virus Shedding/drug effects
2.
J Am Chem Soc ; 144(6): 2474-2478, 2022 02 16.
Article in English | MEDLINE | ID: mdl-35129341

ABSTRACT

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.


Subject(s)
Antigens, Bacterial/chemistry , Borrelia burgdorferi/chemistry , Galactolipids/chemistry , Animals , Antigens, Bacterial/pharmacology , Bone Marrow Cells/drug effects , Bone Marrow Cells/metabolism , Dendritic Cells/drug effects , Dendritic Cells/metabolism , Galactolipids/chemical synthesis , Galactolipids/pharmacology , Inflammation/chemically induced , Lyme Disease/immunology , Mice , Toll-Like Receptor 2/metabolism , Tumor Necrosis Factor-alpha/metabolism
3.
PLoS One ; 14(7): e0219305, 2019.
Article in English | MEDLINE | ID: mdl-31310628

ABSTRACT

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.


Subject(s)
Antiviral Agents/pharmacology , Galactolipids/pharmacology , Herpes Genitalis/therapy , Herpesvirus 2, Human/drug effects , Microalgae/chemistry , Administration, Intravaginal , Animals , Antiviral Agents/analysis , Chlorocebus aethiops , Disease Models, Animal , Fatty Acids, Unsaturated/analysis , Female , Galactolipids/analysis , Herpes Genitalis/virology , Mice , Mice, Inbred BALB C , Particle Size , Vero Cells , alpha-Linolenic Acid/analysis
4.
Int J Mol Sci ; 18(9)2017 Sep 03.
Article in English | MEDLINE | ID: mdl-28869526

ABSTRACT

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.


Subject(s)
Antigens, Viral/chemistry , Antigens, Viral/immunology , Hemagglutinin Glycoproteins, Influenza Virus/chemistry , Hemagglutinin Glycoproteins, Influenza Virus/immunology , Influenza A Virus, H1N1 Subtype/immunology , Adjuvants, Immunologic/chemistry , Animals , Antibodies, Viral/immunology , Calorimetry, Differential Scanning , Cytokines/metabolism , Galactolipids/chemistry , Galactolipids/pharmacology , Influenza Vaccines/immunology , Macrophages/drug effects , Macrophages/immunology , Macrophages/metabolism , Male , Mice , Protein Conformation/drug effects , Protein Denaturation
5.
Exp Neurol ; 289: 64-72, 2017 03.
Article in English | MEDLINE | ID: mdl-28013000

ABSTRACT

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.


Subject(s)
Biogenic Monoamines/metabolism , Depression , Galanin/metabolism , Locus Coeruleus/pathology , Raphe Nuclei/pathology , Status Epilepticus/complications , Animals , Antidepressive Agents/pharmacology , Depression/etiology , Depression/metabolism , Depression/pathology , Disease Models, Animal , Drug Delivery Systems , Galactolipids/pharmacology , Galanin/antagonists & inhibitors , Galanin/pharmacology , Impulsive Behavior/drug effects , Impulsive Behavior/physiology , Lithium Chloride/therapeutic use , Locus Coeruleus/diagnostic imaging , Male , Muscarinic Agonists/toxicity , Peptide Fragments/pharmacology , Pilocarpine/toxicity , Raphe Nuclei/drug effects , Rats , Rats, Wistar , Serotonin/metabolism , Status Epilepticus/chemically induced , Swimming/psychology
6.
Radiat Oncol ; 11(1): 153, 2016 Nov 22.
Article in English | MEDLINE | ID: mdl-27876069

ABSTRACT

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.


Subject(s)
Chemoradiotherapy/methods , Galactolipids/pharmacology , Pancreatic Neoplasms/pathology , Plant Extracts/pharmacology , Radiation-Sensitizing Agents/pharmacology , Spinacia oleracea , Animals , Apoptosis/drug effects , Apoptosis/radiation effects , Blotting, Western , Cell Line, Tumor , Comet Assay , DNA Damage/drug effects , DNA Damage/radiation effects , DNA Repair/drug effects , DNA Repair/radiation effects , Humans , Male , Mice , Mice, Inbred BALB C , Xenograft Model Antitumor Assays
7.
Angew Chem Int Ed Engl ; 55(46): 14330-14334, 2016 11 07.
Article in English | MEDLINE | ID: mdl-27762087

ABSTRACT

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.


Subject(s)
Galactolipids/chemistry , Glycolipids/chemistry , Proteins/chemistry , Alkynes/chemistry , Chondrocytes/cytology , Chondrocytes/drug effects , Chondrocytes/metabolism , Click Chemistry , Diazomethane/chemistry , Electrophoresis, Polyacrylamide Gel , Galactolipids/pharmacology , Humans , Lymphocyte Antigen 96/chemistry , Lymphocyte Antigen 96/metabolism , Mass Spectrometry , Proteins/metabolism , Toll-Like Receptor 4/chemistry , Toll-Like Receptor 4/metabolism , Ultraviolet Rays
8.
J Agric Food Chem ; 64(46): 8783-8794, 2016 Nov 23.
Article in English | MEDLINE | ID: mdl-27786470

ABSTRACT

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.


Subject(s)
Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/pharmacology , Galactolipids/chemistry , Galactolipids/pharmacology , Galactosylceramides/pharmacology , Haptophyta/chemistry , Microalgae/chemistry , Anti-Inflammatory Agents/isolation & purification , Galactolipids/isolation & purification , Galactosylceramides/isolation & purification , Humans , Macrophages/drug effects , Macrophages/immunology , Molecular Structure , Tandem Mass Spectrometry , Tumor Necrosis Factor-alpha/immunology
9.
Nat Prod Res ; 30(10): 1219-23, 2016.
Article in English | MEDLINE | ID: mdl-26181315

ABSTRACT

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.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Galactolipids/pharmacology , Hyaluronoglucosaminidase/antagonists & inhibitors , Impatiens/chemistry , Plant Extracts/chemistry , Anti-Inflammatory Agents/isolation & purification , Enzyme Inhibitors/isolation & purification , Enzyme Inhibitors/pharmacology , Galactolipids/isolation & purification , Plant Leaves/chemistry
10.
Carbohydr Res ; 408: 114-8, 2015 May 18.
Article in English | MEDLINE | ID: mdl-25683967

ABSTRACT

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.


Subject(s)
DNA Damage , Galactolipids/chemistry , Galactolipids/pharmacology , Multiple Myeloma/genetics , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Apoptosis , Cell Line, Tumor , Cell Survival/drug effects , Drug Synergism , Humans , Poly(ADP-ribose) Polymerases/metabolism
11.
J Agric Food Chem ; 62(46): 11157-62, 2014 Nov 19.
Article in English | MEDLINE | ID: mdl-25363514

ABSTRACT

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.


Subject(s)
Adipocytes/drug effects , Galactolipids/pharmacology , Plant Extracts/pharmacology , Sargassum/chemistry , Seaweed/chemistry , Triglycerides/metabolism , 3T3 Cells , Adipocytes/metabolism , Animals , Galactolipids/chemistry , Galactolipids/isolation & purification , Mass Spectrometry , Mice , Molecular Structure , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Structure-Activity Relationship , Vegetables/chemistry
12.
Biochem Biophys Res Commun ; 452(3): 347-53, 2014 Sep 26.
Article in English | MEDLINE | ID: mdl-25152404

ABSTRACT

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.


Subject(s)
Galanin/pharmacology , Hippocampus/metabolism , Neurons/metabolism , Peptide Fragments/pharmacology , Receptor, Galanin, Type 1/metabolism , Receptor, Galanin, Type 2/metabolism , Allosteric Regulation , Animals , Bradykinin/analogs & derivatives , Bradykinin/pharmacology , Brain Mapping , CREB-Binding Protein/antagonists & inhibitors , CREB-Binding Protein/genetics , CREB-Binding Protein/metabolism , Galactolipids/pharmacology , Galanin/metabolism , Gene Expression Regulation , Genes, Reporter , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , HEK293 Cells , Hippocampus/cytology , Hippocampus/drug effects , Humans , Neurons/cytology , Neurons/drug effects , Peptide Fragments/metabolism , Promoter Regions, Genetic , Protein Multimerization , Rats , Receptor, Galanin, Type 1/agonists , Receptor, Galanin, Type 1/chemistry , Receptor, Galanin, Type 1/genetics , Receptor, Galanin, Type 2/chemistry , Receptor, Galanin, Type 2/genetics , Signal Transduction
13.
J Nat Med ; 68(1): 31-7, 2014 Jan.
Article in English | MEDLINE | ID: mdl-23508568

ABSTRACT

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.


Subject(s)
Ferns , Galactolipids/pharmacology , Keratinocytes/drug effects , Plant Extracts/pharmacology , Wound Healing/drug effects , Calcium Signaling/drug effects , Cell Line , Dose-Response Relationship, Drug , Ferns/chemistry , Galactolipids/isolation & purification , Humans , Keratinocytes/metabolism , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 1/pharmacology , Mitogen-Activated Protein Kinase 3/metabolism , Mitogen-Activated Protein Kinase 3/pharmacology , Phytotherapy , Plant Extracts/isolation & purification , Plant Leaves , Plants, Medicinal
14.
Carbohydr Res ; 376: 15-23, 2013 Jul 19.
Article in English | MEDLINE | ID: mdl-23727703

ABSTRACT

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.


Subject(s)
Galactolipids/chemical synthesis , Protein Kinase Inhibitors/chemical synthesis , Carbohydrate Conformation , Galactolipids/chemistry , Galactolipids/pharmacology , Humans , Membrane Proteins/antagonists & inhibitors , Membrane Proteins/metabolism , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/pharmacology , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein Serine-Threonine Kinases/metabolism , Protein-Tyrosine Kinases/antagonists & inhibitors , Protein-Tyrosine Kinases/metabolism , Structure-Activity Relationship
15.
Nat Prod Res ; 27(12): 1084-90, 2013.
Article in English | MEDLINE | ID: mdl-22973805

ABSTRACT

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.


Subject(s)
Chlorophyta/chemistry , Galactolipids/chemistry , Galactolipids/pharmacology , Macrophages/drug effects , Nitric Oxide/metabolism , Animals , Arginine/analogs & derivatives , Cell Line/drug effects , Enzyme Inhibitors/pharmacology , Fatty Acids, Unsaturated/chemistry , Galactosides/chemistry , Galactosides/pharmacology , Glycerol/analogs & derivatives , Glycerol/chemistry , Glycerol/pharmacology , Lipopolysaccharides/pharmacology , Macrophages/metabolism , Mice , Microalgae/chemistry , Molecular Structure , Nitric Oxide Synthase Type II/antagonists & inhibitors , Structure-Activity Relationship
16.
Biochim Biophys Acta ; 1830(3): 2517-25, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23174220

ABSTRACT

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.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/pharmacology , Enzyme Inhibitors/pharmacology , Galactolipids/pharmacology , Neoplasm Proteins/antagonists & inhibitors , Nucleic Acid Synthesis Inhibitors , Spinacia oleracea/chemistry , Animals , Antimetabolites, Antineoplastic/chemistry , Antimetabolites, Antineoplastic/pharmacology , Apoptosis/drug effects , Carcinoma/drug therapy , Carcinoma/metabolism , Carcinoma/pathology , Cattle , Cell Cycle/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , DNA-Directed DNA Polymerase/metabolism , Deoxycytidine/analogs & derivatives , Deoxycytidine/chemistry , Deoxycytidine/pharmacology , Drug Synergism , Enzyme Inhibitors/isolation & purification , Galactolipids/isolation & purification , Humans , Isoenzymes/antagonists & inhibitors , Isoenzymes/metabolism , Kinetics , Neoplasm Proteins/metabolism , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/metabolism , Pancreatic Neoplasms/pathology , Plant Extracts/chemistry , Rats , Gemcitabine
17.
Mar Drugs ; 10(4): 918-931, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22690151

ABSTRACT

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.


Subject(s)
Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Glycolipids/chemistry , Glycolipids/pharmacology , Herpesvirus 1, Human/drug effects , Herpesvirus 2, Human/drug effects , Rhodophyta/chemistry , Animals , Antiviral Agents/isolation & purification , Brazil , Galactolipids/chemistry , Galactolipids/isolation & purification , Galactolipids/pharmacology , Glycolipids/isolation & purification , Lipids/chemistry , Lipids/isolation & purification , Lipids/pharmacology , Magnetic Resonance Spectroscopy/methods , Mass Spectrometry/methods , Vero Cells
18.
Biochim Biophys Acta ; 1823(5): 1033-40, 2012 May.
Article in English | MEDLINE | ID: mdl-22425965

ABSTRACT

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.


Subject(s)
Chloroplast Proteins/metabolism , Chloroplasts/metabolism , Intracellular Membranes/metabolism , Lipids/pharmacology , Protein Precursors/metabolism , Chloroplasts/drug effects , Fluorescent Dyes/metabolism , Galactolipids/pharmacology , Intracellular Membranes/drug effects , Pisum sativum/metabolism , Protein Binding/drug effects , Protein Transport/drug effects , Ribulose-Bisphosphate Carboxylase/metabolism , Unilamellar Liposomes/metabolism
19.
Eur J Med Chem ; 50: 230-5, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22348826

ABSTRACT

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.


Subject(s)
Bauhinia/chemistry , Brugia malayi/drug effects , Elephantiasis, Filarial/drug therapy , Filaricides/isolation & purification , Filaricides/pharmacology , Galactolipids/isolation & purification , Galactolipids/pharmacology , Animals , Anthelmintics/isolation & purification , Anthelmintics/pharmacology , Diethylcarbamazine/therapeutic use , Elephantiasis, Filarial/parasitology , Humans , Ivermectin/therapeutic use , Plant Extracts/pharmacology , Plant Leaves/chemistry
20.
Bioorg Med Chem Lett ; 22(5): 2030-2, 2012 Mar 01.
Article in English | MEDLINE | ID: mdl-22326167

ABSTRACT

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.


Subject(s)
Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Galactolipids/chemistry , Galactolipids/pharmacology , Cell Line, Tumor , Cell Survival/drug effects , Drug Synergism , Humans , Neoplasms/drug therapy
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