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1.
Biochem Biophys Res Commun ; 710: 149881, 2024 May 28.
Article En | MEDLINE | ID: mdl-38583233

Maackia amurensis lectins serve as research and botanical agents that bind to sialic residues on proteins. For example, M. amurensis seed lectin (MASL) targets the sialic acid modified podoplanin (PDPN) receptor to suppress arthritic chondrocyte inflammation, and inhibit tumor cell growth and motility. However, M. amurensis lectin nomenclature and composition are not clearly defined. Here, we sought to definitively characterize MASL and its effects on tumor cell behavior. We utilized SDS-PAGE and LC-MS/MS to find that M. amurensis lectins can be divided into two groups. MASL is a member of one group which is composed of subunits that form dimers, evidently mediated by a cysteine residue in the carboxy region of the protein. In contrast to MASL, members of the other group do not dimerize under nonreducing conditions. These data also indicate that MASL is composed of 4 isoforms with an identical amino acid sequence, but unique glycosylation sites. We also produced a novel recombinant soluble human PDPN receptor (shPDPN) with 17 threonine residues glycosylated with sialic acid moieties with potential to act as a ligand trap that inhibits OSCC cell growth and motility. In addition, we report here that MASL targets PDPN with very strong binding kinetics in the nanomolar range. Moreover, we confirm that MASL can inhibit the growth and motility of human oral squamous cell carcinoma (OSCC) cells that express the PDPN receptor. Taken together, these data characterize M. amurensis lectins into two major groups based on their intrinsic properties, clarify the composition of MASL and its subunit isoform sequence and glycosylation sites, define sialic acid modifications on the PDPN receptor and its ability to act as a ligand trap, quantitate MASL binding to PDPN with KD in the nanomolar range, and verify the ability of MASL to serve as a potential anticancer agent.


Antineoplastic Agents , Carcinoma, Squamous Cell , Head and Neck Neoplasms , Mouth Neoplasms , Humans , Carcinoma, Squamous Cell/pathology , Squamous Cell Carcinoma of Head and Neck , N-Acetylneuraminic Acid/metabolism , Maackia/chemistry , Maackia/metabolism , Mouth Neoplasms/pathology , Chromatography, Liquid , Ligands , Tandem Mass Spectrometry , Lectins/pharmacology , Antineoplastic Agents/pharmacology , Sequence Analysis , Cell Movement
2.
Molecules ; 28(6)2023 Mar 13.
Article En | MEDLINE | ID: mdl-36985562

In this study, we isolated a new isoflavanostilbene maackiapicevestitol (1) as a mixture of two stable conformers 1a and 1b as well as five previously known dimeric and monomeric stilbens: piceatannol (2), maackin (3), scirpusin A (4), maackiasine (5), and maackolin (6) from M. amurensis heartwood, using column chromatography on polyamide, silicagel, and C-18. The structures of these compounds were elucidated by NMR, HR-MS, and CD techniques. Maksar® obtained from M. amurensis heartwood and polyphenolics 1-6 possessed moderate anti-HSV-1 activity in cytopathic effect (CPE) inhibition and RT-PCR assays. A model of PQ-induced neurotoxicity was used to study the neuroprotective potential of polyphenolic compounds from M. amurensis. Maksar® showed the highest neuroprotective activity and increased cell viability by 18% at a concentration of 10 µg/mL. Maackolin (6) also effectively increased the viability of PQ-treated Neuro-2a cells and the value of mitochondrial membrane potential at concentrations up to 10 µΜ. Maksar® and compounds 1-6 possessed higher FRAP and DPPH-scavenging effects than quercetin. However, only compounds 1 and 4 at concentrations of 10 µM as well as Maksar® (10 µg/mL) statistically significantly reduced the level of intracellular ROS in PQ-treated Neuro-2a cells.


Maackia , Plant Extracts , Maackia/chemistry , Plant Extracts/pharmacology , Plant Extracts/chemistry , Quercetin
3.
Exp Cell Res ; 410(1): 112949, 2022 01 01.
Article En | MEDLINE | ID: mdl-34843714

Glioma stem/initiating cells have been considered a major cause of tumor recurrence and therapeutic resistance. In this study, we have established a new glioma stem-like cell (GSC), named U373-GSC, from the U373 glioma cell line. The cells exhibited stemness properties, e.g., expression of stem cell markers, self-renewal activity, multi-lineage differentiating abilities, and drug resistance. Using U373-GSC and GSC-03A-a GSC clone previously established from patient tissue, we have identified a novel GSC-associated sialic acid-modified glycan commonly expressed in both cell lines. Lectin fluorescence staining showed that Maackia amurensis lectin II (MAL-II)-binding alpha2,3-sialylated glycan (MAL-SG) was highly expressed in GSCs, and drastically decreased during FBS induced differentiation to glioma cells or little in the parental cells. Treatment of GSCs by MAL-II, compared with other lectins, showed that MAL-II significantly suppresses cell viability and sphere formation via induction of cell cycle arrest and apoptosis of the GSCs. Similar effects were observed when the cells were treated with a sialyltransferase inhibitor or sialidase. Taken together, we demonstrate for the first time that MAL-SGs/alpha-2,3 sialylations are upregulated and control survival/maintenances of GSCs, and their functional inhibitions lead to apoptosis of GSCs. MAL-SG could be a potential marker and therapeutic target of GSCs; its inhibitors, such as MAL-II, may be useful for glioma treatment in the future.


Glioma/drug therapy , Lectins/pharmacology , Maackia/chemistry , Neoplastic Stem Cells/drug effects , Apoptosis/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Gene Expression Regulation, Neoplastic , Humans , Lectins/chemistry , Polysaccharides/antagonists & inhibitors , Polysaccharides/chemistry , Sialyltransferases/chemistry
4.
J Cancer Res Clin Oncol ; 147(2): 445-457, 2021 Feb.
Article En | MEDLINE | ID: mdl-33205348

PURPOSE: Oral cancer causes over 120,000 deaths annually and affects the quality of life for survivors. Over 90% of oral cancers are derived from oral squamous cell carcinoma cells (OSCCs) which are generally resistant to standard cytotoxic chemotherapy agents. OSCC cells often exhibit increased TGFß and PDPN receptor activity compared to nontransformed oral epithelial cells. Maackia amurensis seed lectin (MASL) can target the PDPN receptor and has been identified as a novel agent that can be used to treat oral cancer. However, mechanisms by which MASL inhibits OSCC progression are not yet clearly defined. METHODS: Here, we performed cell migration and cytotoxicity assays to assess the effects of MASL on OSCC motility and viability at physiologically relevant concentrations. We then performed comprehensive transcriptome analysis combined with transcription factor reporter assays to investigate the how MASL affects OSCC gene expression at these concentration. Key data were then confirmed by western blotting to evaluate the effects of MASL on gene expression and kinase signaling activity at the protein level. RESULTS: MASL significantly affected the expression of about 27% of approximately 15,000 genes found to be expressed by HSC-2 cells used to model OSCC cells in this study. These genes affected by MASL include members of the TGFß-SMAD, JAK-STAT, and Wnt-ßCTN signaling pathways. In particular, MASL decreased expression of PDPN, SOX2, and SMAD5 at the RNA and protein levels. MASL also inhibited SMAD and MAPK activity, and exhibited potential for combination therapy with doxorubicin and 5-fluorouracil. CONCLUSIONS: Taken together, results from this study indicate that MASL decreases activity of JAK-STAT, TGFß-SMAD, and Wnt-ßCTN signaling pathways to inhibit OSCC growth and motility. These data suggest that further studies should be undertaken to determine how MASL may also be used alone and in combination with other agents to treat oral cancer.


Gene Expression Regulation, Neoplastic/drug effects , Maackia/chemistry , Mouth Neoplasms/drug therapy , Plant Lectins/pharmacology , Squamous Cell Carcinoma of Head and Neck/drug therapy , Cell Movement/drug effects , Humans , Mouth Neoplasms/metabolism , Mouth Neoplasms/pathology , Plant Lectins/therapeutic use , SOXB1 Transcription Factors/genetics , Signal Transduction/drug effects , Smad Proteins/genetics , Squamous Cell Carcinoma of Head and Neck/metabolism , Squamous Cell Carcinoma of Head and Neck/pathology , Transcription, Genetic/drug effects , Wnt Signaling Pathway/drug effects
5.
Chem Commun (Camb) ; 56(55): 7549-7552, 2020 Jul 14.
Article En | MEDLINE | ID: mdl-32579622

A facile enzymatic modular assembly strategy for the preparative-scale synthesis of poly-N-acetyllactosamine (poly-LacNAc) glycans with varied lengths and designed sialylation and/or fucosylation patterns is described. These glycans were printed as a microarray to investigate their interactions with a panel of glycan binding proteins (GBPs). Binding affinities revealed that the avidity of GBPs could be largely affected by the length and the patterns of sialylation and fucosylation.


Glycosyltransferases/chemistry , Polysaccharides/chemical synthesis , Ascomycota/chemistry , Bacteria/enzymology , Bacterial Proteins/chemistry , Carbohydrate Sequence , E-Selectin/metabolism , Glycosylation , Griffonia/chemistry , Hemagglutinins/metabolism , Humans , Lectins/metabolism , Maackia/chemistry , Microarray Analysis , Molecular Structure , Plant Lectins/metabolism , Polysaccharides/metabolism
6.
Int J Biol Macromol ; 151: 441-448, 2020 May 15.
Article En | MEDLINE | ID: mdl-32087226

Nineteen compounds were isolated from the stems of Maackia amurensis by activity-guided screening for new human monoamine oxidase-B (hMAO-B) inhibitors. Among the compounds isolated, flavonoids calycosin (5) and 8-O-methylretusin (6) were found to potently and selectively inhibit hMAO-B (IC50 = 0.24 and 0.23 µM, respectively) but not hMAO-A with high selectivity index (SI) values (SI = 293.8 and 81.3, respectively). In addition, 5 and 6 reversibly and competitively inhibited hMAO-B with Ki values of 0.057 and 0.054 µM, respectively. A pterocarpan (-)-medicarpin (18) was also observed to strongly inhibit hMAO-B (IC50 = 0.30 µM). Most of the compounds weakly inhibited AChE, except isolupalbigenin (13) (IC50 = 20.6 µM), which suggested 13 be considered a potential dual function inhibitor of MAO-B and AChE. Molecular docking simulation revealed that the binding affinities of 5 and 6 for hMAO-B (both -9.3 kcal/mol) were higher than those for hMAO-A (-7.4 and -7.2 kcal/mol, respectively). Compound 5 was found to interact by hydrogen bonding with hMAO-B at Cys172 residue (distance: 3.250 Å); no hydrogen bonding was predicted between 5 and hMAO-A. These findings suggest that compounds 5 and 6 be considered novel potent, selective, and reversible hMAO-B inhibitors and candidates for the treatment of neurological disorders.


Isoflavones/chemistry , Isoflavones/pharmacology , Maackia/chemistry , Monoamine Oxidase Inhibitors/chemistry , Monoamine Oxidase Inhibitors/pharmacology , Plant Extracts/pharmacology , Dose-Response Relationship, Drug , Enzyme Activation/drug effects , Humans , Isoflavones/isolation & purification , Kinetics , Molecular Conformation , Molecular Docking Simulation , Molecular Dynamics Simulation , Molecular Structure , Monoamine Oxidase Inhibitors/isolation & purification , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Structure-Activity Relationship
7.
Glycoconj J ; 36(6): 473-485, 2019 12.
Article En | MEDLINE | ID: mdl-31758295

The emergence of multi drug resistance in non-small cell lung cancer (NSCLC) patients is a major challenge towards the efficacy of chemotherapy. Thus, there is an urgent need for the newer, better clinically targeted strategies to treat this disease. Earlier studies from our laboratory revealed the apoptotic activity of Maackia amurensis agglutinin (MAA) in human NSCLC cells. In this study, the effect of MAA on drug resistant NSCLC cells was investigated. Two Paclitaxel-resistant NSCLC sub-lines (A549/PTX100 and NCI-H460/PTX100) were developed from A549 & NCI-H460 cell lines respectively. The generation of drug resistance phenotype was confirmed by the expression of cell surface MDR-1. Both the drug resistant sub-lines showed distinct morphological alterations. MAA interacted with the cell-surface protein(s) of apparent Mr ~66 kDa and induced apoptosis in both the sub-lines through intrinsic/mitochondrial pathway, involving reduction in mitochondrial trans-membrane potential, up-regulation of Bax, unaltered/decreased expression of Bcl-XL, release of mitochondrial cytochrome c into the cytosol and activation of pro-caspases (-9&-3). Our findings highlighted the potential of this plant agglutinin to serve as an apoptosis inducing agent in drug resistant NSCLC cells.


Agglutinins/pharmacology , Carcinoma, Non-Small-Cell Lung/drug therapy , Cell Proliferation/drug effects , Maackia/chemistry , A549 Cells , Agglutinins/chemistry , Apoptosis/drug effects , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Caspases/genetics , Drug Resistance, Neoplasm/drug effects , Gene Expression Regulation, Neoplastic/drug effects , Humans , Membrane Potential, Mitochondrial/drug effects , bcl-X Protein/genetics
8.
Molecules ; 24(20)2019 Oct 22.
Article En | MEDLINE | ID: mdl-31652515

In light of the immunoprotective function of human milk and the incontestable impact of IgG glycosylation on its immune functions, characterization of the sialylation profile of human milk IgG is needed. Lectins as a molecular probe were applied in lectin-IgG-ELISA to analyze the sialylation and galactosylation pattern of skim milk IgG of mothers who delivered at term and prematurely. Well-defined biotinylated lectins were used: Maackia amurensis II (MAA II), Sambucus nigra (SNA), Ricinus communis I (RCA I), and Griffonia simplicifolia II (GSL II) specific to α2,3-Neu5Ac, α2,6-Neu5Ac, Gal(ß1,4)GlcNAc, and agalactosylated glycans, respectively. The sialylation pattern of milk IgG differs qualitatively and quantitatively from maternal plasma IgG and is related to lactation stage and perinatal risk factors. Expression of MAA-, SNA-, and GSL-reactive glycotopes on term milk IgG showed a positive correlation with milk maturation from days 1 to 55. Preterm birth was associated with an increase of MAA-reactive and a decrease of RCA-reactive IgG glycotopes. Moreover, higher SNA- and GSL-reactive and lower RCA-reactive glycoform levels of milk IgG were associated with infection of lactating mothers. Application of a specific and simple method, lectin-IgG-ELISA, reveals the sialylation pattern of milk IgG over milk maturation. However, further investigations are needed in this area.


Immunoglobulin G/metabolism , Milk, Human/immunology , N-Acetylneuraminic Acid/metabolism , Plant Lectins/metabolism , Adult , Enzyme-Linked Immunosorbent Assay , Female , Glycosylation , Griffonia/chemistry , Griffonia/metabolism , Humans , Immunoglobulin G/chemistry , Infections/metabolism , Lactation/immunology , Lactation/metabolism , Maackia/chemistry , Maackia/metabolism , Polysaccharides/metabolism , Pregnancy , Premature Birth/metabolism , Ricinus/chemistry , Ricinus/metabolism , Sambucus nigra/chemistry , Sambucus nigra/metabolism
9.
Adv Med Sci ; 63(1): 205-211, 2018 Mar.
Article En | MEDLINE | ID: mdl-29197783

PURPOSE: Attachment of Helicobacter pylori to the mucous epithelial cells and the mucous layer is said to be a crucial step for infection development. Sugar antigens of gastric mucins (MUC5AC, MUC1) can act as receptors for bacterial adhesins. The aim of the study was to investigate if Lotus tetragonolobus and Maackia amurensis lectins influence the level of MUC1, MUC5AC, Lewis b, H type 1, sialyl Lewis x, phospho-IκBα and interleukin 8 in Helicobacter pylori infected gastric cancer cells. MATERIALS AND METHODS: The study was performed with one clinical H. pylori strain and CRL-1739 gastric cancer cells. To assess the levels of mentioned factors immunosorbent ELISA assays were used. RESULTS: Coculture of cells with bacteria had no clear effect on almost all examined structures. After coculture with H. pylori and lectins, a decrease of the level of both mucins, Lewis b and H type 1 antigens was observed. Lectins addition had no effect on sialyl Lewis x. Maackia amurensis caused slight increase of phospho-IκBα while interleukin 8 level was decreased. CONCLUSIONS: Lotus tetragonolobus and Maackia amurensis lectins can mediate in binding of Helicobacter pylori to gastric epithelium.


Antigens, Tumor-Associated, Carbohydrate/metabolism , Helicobacter pylori/physiology , Interleukin-8/metabolism , Lectins/therapeutic use , Lotus/chemistry , Maackia/chemistry , NF-KappaB Inhibitor alpha/metabolism , Stomach Neoplasms/drug therapy , Stomach Neoplasms/microbiology , Cell Line, Tumor , Helicobacter pylori/drug effects , Humans , Lectins/pharmacology , Mucins/metabolism , Phosphorylation/drug effects
10.
Sci Rep ; 7(1): 6477, 2017 07 25.
Article En | MEDLINE | ID: mdl-28743896

There is an urgent need for discovery of novel antimicrobials and carbohydrate-based anti-adhesive strategies are desirable as they may not promote resistance. Discovery of novel anti-adhesive molecules from natural product libraries will require the use of a high throughput screening platform. Avian egg white (EW) provides nutrition for the embryo and protects against infection, with glycosylation responsible for binding certain pathogens. In this study, a microarray platform of 78 species of avian EWs was developed and profiled for glycosylation using a lectin panel with a wide range of carbohydrate specificities. The dominating linkages of sialic acid in EWs were determined for the first time using the lectins MAA and SNA-I. EW glycosylation similarity among the different orders of birds did not strictly depend on phylogenetic relationship. The interactions of five strains of bacterial pathogens, including Escherichia coli, Staphylococcus aureus and Vibrio cholera, identified a number of EWs as potential anti-adhesives, with some as strain- or species-specific. Of the two bacterial toxins examined, shiga-like toxin 1 subunit B bound to ten EWs with similar glycosylation more intensely than pigeon EW. This study provides a unique platform for high throughput screening of natural products for specific glycosylation and pathogen interactions. This platform may provide a useful platform in the future for discovery of anti-adhesives targeted for strain and species specificity.


Egg White , Food Microbiology , Glycoproteins/metabolism , High-Throughput Screening Assays/methods , Host-Pathogen Interactions/physiology , Agglutinins/chemistry , Agglutinins/metabolism , Animals , Bacterial Toxins/metabolism , Birds , Electrophoresis, Polyacrylamide Gel , Glycoproteins/analysis , Glycosylation , Maackia/chemistry , Phylogeny , Protein Array Analysis/methods , Sialic Acids/chemistry , Sialic Acids/metabolism
11.
Bioelectrochemistry ; 117: 89-94, 2017 Oct.
Article En | MEDLINE | ID: mdl-28651174

In recent decades, it has become clear that most of human proteins are glycosylated and that protein glycosylation plays an important role in health and diseases. At present, simple, fast and inexpensive methods are sought for clinical applications and particularly for improved diagnostics of various diseases, including cancer. We propose a label- and reagent-free electrochemical method based on chronopotentiometric stripping (CPS) analysis and a hanging mercury drop electrode for the detection of interaction of sialylated protein biomarker a prostate specific antigen (PSA) with two important lectins: Sambucus nigra agglutinin (SNA) and Maackia amurensis agglutinin (MAA). Incubation of PSA-modified electrode with specific SNA lectin resulted in an increase of CPS peak H of the complex as compared to this peak of individual PSA. By adjusting polarization current and temperature, PSA-MAA interaction can be either eliminated or distinguished from the more abundant PSA-SNA complex. CPS data were in a good agreement with the data obtained by complementary methods, namely surface plasmon resonance and fluorescent lectin microarray. It can be anticipated that CPS will find application in glycomics and proteomics.


Agglutinins/metabolism , Electric Conductivity , N-Acetylneuraminic Acid/metabolism , Prostate-Specific Antigen/chemistry , Prostate-Specific Antigen/metabolism , Electrochemistry , Maackia/chemistry , Sambucus nigra/chemistry
12.
Biomed Res Int ; 2017: 4941825, 2017.
Article En | MEDLINE | ID: mdl-28484711

Oxidative stress and aldose reductase activity have been implicated in the development of diabetic complications. In this study, the antioxidant and aldose reductase (AR) inhibitory effects of Maackia amurensis (MA) were investigated. The ethyl acetate fraction of the MA extract showed the highest inhibitory activity in antioxidant and rat lens AR (RLAR). To identify and isolate the active components in the ethyl acetate fraction of the MA extract, high-speed countercurrent chromatography and Sephadex LH-20 column chromatography were performed and guided by an offline HPLC-ABTS assay and HPLC microfractionation AR assay. Four antioxidants, namely, piceatannol (IC50 = 6.73 µM), resveratrol (IC50 = 11.05 µM), trans-ferulic acid (IC50 = 13.51 µM), and chlorogenic acid (IC50 = 27.23 µM), and six AR inhibitors, namely, chlorogenic acid (IC50 = 4.2 µM), tectoridin (IC50 = 50.4 µM), genistein (IC50 = 57.1 µM), formononetin (IC50 = 69.2 µM), resveratrol (IC50 = 117.6 µM), and daidzein (IC50 = 151.9 µM), were isolated and identified. The screening results of the offline HPLC-ABTS assay and HPLC microfractionation AR assay matched the activity of isolated compounds. Thus, MA is potentially valuable for antioxidant and AR inhibitor discovery and efficient drug design for the prevention and treatment of diabetic complications.


Aldehyde Reductase/antagonists & inhibitors , Antioxidants , Enzyme Inhibitors , Lens, Crystalline/enzymology , Maackia/chemistry , Animals , Antioxidants/chemistry , Antioxidants/isolation & purification , Antioxidants/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/isolation & purification , Enzyme Inhibitors/pharmacology , Rats
13.
Int J Oncol ; 50(4): 1201-1210, 2017 Apr.
Article En | MEDLINE | ID: mdl-28259967

Gastric cancer (GC) is a highly metastatic disease and one of the leading causes of cancer death in the world. Aberrant glycosylation is one of many molecular changes that accompany malignant transformation. This study was aimed at identification of glycan profiling changes in GC progression and its potential mechanisms. We employed a microarray with 91 lectins to compare the differential glycans in the three human GC cell lines, SGC-7901, BGC-823 and MGC-803. According to glycan-binding specificities of lectins, all GC cell lines expressed common sugar structures, such as mannose, galactose and fucose. Importantly, we found that the binding of Maackia amurensis lectin-I (MAL-I) to GC cells was proportional to their metastatic capacity. Further analysis revealed that the level of α2,3-linked sialic acids (α2-3Sia), which can be recognized by MAL-I, was significantly overexpressed in MGC-803 cells, while low expression was detected in SGC-7901 cells. In addition, the mRNA and protein expression levels of ß-galactoside α2,3-sialyltransferase IV (ST3Gal-IV), which was related to the synthesis of α2-3Sia, were substantially increased in MGC-803 cells. Knockdown of ST3Gal-IV in MGC-803 cells led to a decreased level of α2-3Sia and decreased ability of invasion and migration. Exogenous expression of ST3Gal-IV in SGC-7901 cells enhanced cell migration, invasion and the content of α2-3Sia. Furthermore, the staining of MAL-I in GC tissues showed that high expression of α2-3Sia was closely correlated with lymph node metastasis, TNM stage and poor overall survival. These findings lead to better understanding of the function of α2-3Sia in the progression and metastasis of GC. This property may be important for developing new therapeutic approaches for GC.


Hexoses/metabolism , Lectins/metabolism , Sialic Acids/biosynthesis , Sialyltransferases/metabolism , Stomach Neoplasms/metabolism , Stomach Neoplasms/pathology , Biomarkers, Tumor/biosynthesis , Cell Line, Tumor , Cell Membrane/metabolism , Cell Movement , Female , Galactosides/metabolism , Glycosylation , Humans , Lymphatic Metastasis , Maackia/chemistry , Male , Microarray Analysis , Middle Aged , Molecular Targeted Therapy , Neoplasm Staging , Polysaccharides/metabolism , Prognosis , RNA, Messenger/metabolism , Stomach Neoplasms/drug therapy , beta-Galactoside alpha-2,3-Sialyltransferase
14.
Sci Rep ; 7: 38918, 2017 01 12.
Article En | MEDLINE | ID: mdl-28079114

The accuracy of current biomarkers for the diagnosis of hepatocellular carcinoma (HCC), especially chronic Hepatitis B Virus (HBV)-related HCC, is limited. Recent progress in glycoproteomics has provided a novel platform for screening novel serological biomarkers of HCC. In this study, lectin affinity chromatography by Maackia amurensis lectin (MAL) and iTRAQ combined with mass spectrometric analysis were performed to enrich and identify the glycoprotein fractions in serum samples from HBV-related HCC patients and from healthy controls. Seventeen differential MAL-associated glycoproteins were identified. Among them, Galectin 3 binding protein (Gal-3BP) was selected for further evaluated by ELISA analysis and showed a high diagnostic potential of HBV-related HCC, with the AUC of 0.898 and a sensitivity, specificity and accuracy of 80.00%, 93.75% and 86.88%, respectively. Moreover, we constructed a predictive model through the combined use of serum Gal-3BP and Alpha Fetoprotein (AFP), which improved the sensitivity (from 87.5% to 95%), specificity (from 93.75% to 95%) and accuracy (from 90.63% to 95%) of diagnosing early HCC. These data suggested serum Gal-3BP level is a promising biomarker to identify HBV-related HCC and the combined use of serum Gal-3BP and AFP improves the diagnostic potential of HBV-HCC compared with AFP alone in current clinical practice.


Antigens, Neoplasm/blood , Biomarkers, Tumor/blood , Biomarkers/blood , Carcinoma, Hepatocellular/diagnosis , Carrier Proteins/blood , Glycoproteins/blood , Hepatitis B, Chronic/complications , Liver Neoplasms/diagnosis , alpha-Fetoproteins/analysis , Asian People , Carcinoma, Hepatocellular/pathology , Chromatography, Liquid , Enzyme-Linked Immunosorbent Assay , Humans , Lectins/metabolism , Liver Neoplasms/pathology , Maackia/chemistry , Mass Spectrometry , Sensitivity and Specificity , Serum/chemistry
15.
Int J Biol Macromol ; 94(Pt A): 114-121, 2017 Jan.
Article En | MEDLINE | ID: mdl-27720757

Seeds of Maackia amurensis constitutes two sialic acid specific agglutinins known as leukagglutinin and hemagglutinin. Maackia amurensis leukagglutinin (MAL) recognizes α2-3-linked sialic acid present mainly in N-glycans and composed of two disulfide linked monomers. It exhibits potential N-glycosylation sites (four PNGs) which have been assumed to undergo differential occupancy. In this study we have characterized the site specific macro- and microheterogeneity of monomers in detail by analysing N-glycopeptides and peptides through liquid chromatography coupled to ion trap mass spectrometer in MS3 mode (LC-MSn). We observed the presence of mainly paucimannose N-glycans at Asn61, Asn113 and Asn191 whereas a high mannose type with varying Man5-9 occurs at Asn179. Interestingly Asn179 and Asn191 exhibited differential occupancy which was evident by the presence of non-glycosylated peptides. This has contributed to the difference in molecular mass of monomers upon SDS-PAGE. Further the presence of disulfide linked peptides confirmed the covalent linkage of monomers which also undergoes uniform C-terminal processing.


Maackia/chemistry , Phytohemagglutinins/chemistry , Sialic Acids/chemistry , Amino Acid Sequence , Carbohydrate Conformation , Carbohydrate Sequence , Glycosylation , Protein Processing, Post-Translational , Sequence Analysis, Protein
16.
Phys Chem Chem Phys ; 17(26): 16805-12, 2015 Jul 14.
Article En | MEDLINE | ID: mdl-26058603

The antioxidant isoflavone retusin efficiently attaches low-energy electrons in vacuo, generating fragment species via dissociative electron attachment (DEA), as has been shown by DEA spectroscopy. According to in silico results obtained by means of density functional theory, retusin is able to attach solvated electrons and could be decomposed under reductive conditions in vivo, for instance, near the mitochondrial electron transport chain, analogous to gas-phase DEA. The most intense decay channels of retusin temporary negative ions were found to be associated with the elimination of H atoms and H2 molecules. Doubly dehydrogenated fragment anions were predicted to possess a quinone structure. It is thought that molecular hydrogen, known for its selective antioxidant properties, can be efficiently generated via electron attachment to retusin in mitochondria and may be responsible for its antioxidant activity. The second abundant species, i.e., quinone bearing an excess negative charge, can serve as an electron carrier and can return the captured electron back to the respiration cycle. The number of OH substituents and their relative positions are crucial for the present molecular mechanism, which can explain the radical scavenging activity of polyphenolic compounds.


Antioxidants/metabolism , Electrons , Flavonoids/metabolism , Maackia/metabolism , Antioxidants/chemistry , Antioxidants/isolation & purification , Flavonoids/chemistry , Flavonoids/isolation & purification , Maackia/chemistry , Quantum Theory
17.
Biochimie ; 115: 93-107, 2015 Aug.
Article En | MEDLINE | ID: mdl-25978938

Maackia amurensis agglutinin (MAA) is gaining recognition as the potential diagnostic agent for cancer. Previous studies from our laboratory have demonstrated that this lectin could interact specifically with the cells and biopsy samples of non-small cell lung cancer (NSCLC) origin but not with normal lung fibroblast cells. Moreover, this lectin was also found to induce apoptosis in NSCLC cells. Further, the biological activity of this lectin was shown to survive gastrointestinal proteolysis and inhibit malignant cell growth and tumorigenesis in mice model of melanoma thereby indicating the therapeutic potential of this lectin. Paclitaxel is one of the widely used traditional chemotherapeutic drugs for treatment of NSCLC but it exerts side-effects on normal healthy cells too. Studies have revealed that lectins have potential to act as an adjuvant chemotherapeutic agent in cancer of different origin. Thus, in the present study, an attempt was made to assess the chemo-adjuvant role of MAA in three types of NSCLC cell lines [adenocarcinoma cell line (A549), squamous cell carcinoma cell line (NCI-H520) and large cell carcinoma cell line (NCI-H460)]. We have observed that the non-cytotoxic concentration of this lectin was able to enhance the cytotoxic activity of Paclitaxel even at low dose by inducing apoptosis through intrinsic/mitochondrial pathway in all the three types of NSCLC cell lines, although the involvement of extrinsic pathway of apoptosis in case of NCI-H460 cell line could not be ruled out. Further, this lectin was also found to augment the chemo-preventive activity of this drug by arresting cells in G2-M phase of the cell cycle. Collectively, our results have suggested that Maackia amurensis agglutinin may have the potential to be used as adjuvant chemotherapeutic agent in case of NSCLC.


Agglutinins/pharmacology , Antineoplastic Agents/pharmacology , Carcinoma, Non-Small-Cell Lung/pathology , Lung Neoplasms/pathology , Maackia/chemistry , Paclitaxel/pharmacology , Agglutinins/metabolism , Apoptosis/drug effects , Cell Cycle Checkpoints/drug effects , Cell Line, Tumor , Drug Synergism , Gene Expression Regulation, Neoplastic/drug effects , Humans , Membrane Potential, Mitochondrial/drug effects , Plant Lectins/metabolism
18.
J Asian Nat Prod Res ; 17(2): 178-81, 2015.
Article En | MEDLINE | ID: mdl-25295462

A new prenylated flavanone, erythraddison Z (1), together with eight known flavonoids (2-9), was isolated from the stem bark of Maackia amurensis. Their structures were elucidated on the basis of spectroscopic methods, including 1D and 2D NMR (COSY, HMQC, and HMBC) techniques. All the isolates, with the exception of 3, 6 and 7, strongly inhibited diacylglycerol acyltransferase activity in an in vitro assay with IC50 values ranging from 96.5 ± 0.6 to 135.1 ± 1.4 µM.


Diacylglycerol O-Acyltransferase/antagonists & inhibitors , Drugs, Chinese Herbal/isolation & purification , Drugs, Chinese Herbal/pharmacology , Flavanones/isolation & purification , Flavanones/pharmacology , Maackia/chemistry , Drugs, Chinese Herbal/chemistry , Flavanones/chemistry , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Plant Bark/chemistry , Prenylation
19.
Appl Biochem Biotechnol ; 174(5): 1945-58, 2014 Nov.
Article En | MEDLINE | ID: mdl-25161041

Avian influenza viruses preferentially bind to sialic acid alpha-2,3-galactose (N-SA-α-2,3-Gal) receptors on epithelial cells. Herein, we describe a procedure we have developed for isolation of N-SA-α-2,3-Gal receptors from porcine trachea using magnetic nanoparticles (NPs) coated with chitosan (NP-Ch) and functionalized with Maackia amurensis lectin (NP-lectin). Magnetic nanoparticles were coated with chitosan in a one-step co-precipitation, and then M. amurensis lectin was immobilized covalently using glutaraldehyde. Lectin coated nanoparticles were incubated with sialic acid enriched fraction of tracheal homogenate, and N-SA-α-2,3-Gal receptor was extracted under magnetic field in two cycles. The presence of 66.4 kDa protein was determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The interaction of immobilized receptor (NP-Ch-R) with M. amurensis lectin (NP-Ch-R-L) was demonstrated by Fourier transform infrared spectrometry (FTIR) and thermogravimetric analysis (TGA).


Chitosan/chemistry , Maackia/chemistry , Magnetite Nanoparticles/chemistry , Plant Lectins/chemistry , Receptors, Cell Surface/isolation & purification , Trachea/chemistry , Animals , Coated Materials, Biocompatible/chemical synthesis , Immunomagnetic Separation/methods , Magnetic Fields , Magnetite Nanoparticles/radiation effects , Magnetite Nanoparticles/ultrastructure , Orthomyxoviridae/metabolism , Particle Size , Receptors, Cell Surface/metabolism , Swine
20.
Eksp Klin Farmakol ; 77(2): 26-30, 2014.
Article Ru | MEDLINE | ID: mdl-24791337

Hepatoprotective properties of ethanol extract from the roots of Maackia amurensis Ruper et Maxim have been studied on the model of toxic hepatitis induced by carbon tetrachloride damage. It is established that the extract contains daidzein, 7-O-gentobiosides of isoflavonoids genistein, formononetin, pseudobabtige-nin, and 5-O-methylgenistein, and 3-O-gentobiosides of pterocarpans (6aR, 11aR)-maakiain and (6aR, 11aR)-medicarpin. The administration of extract facilitates the restoration of antioxidant protection enzymes activity and reduced glutathione level, decreases the formation of toxic peroxidation products, produces normalizing impact on liver phospholipid pattern, and improves the erythrocyte tolerance to hemolytic agents. The action of isoflavonoids from Maackia amurensis in restoration of metabolic pathways of the liver and removal of toxic stress was more effective as compared to that of the reference hepatoprotector legalon.


Carbon Tetrachloride Poisoning/drug therapy , Chemical and Drug Induced Liver Injury/drug therapy , Liver/drug effects , Maackia/chemistry , Phytotherapy , Plant Extracts/pharmacology , Protective Agents/pharmacology , Animals , Carbon Tetrachloride Poisoning/metabolism , Carbon Tetrachloride Poisoning/pathology , Chemical and Drug Induced Liver Injury/metabolism , Chemical and Drug Induced Liver Injury/pathology , Genistein/isolation & purification , Glutathione/blood , Glutathione Peroxidase/blood , Glutathione Reductase/blood , Isoflavones/isolation & purification , Liver/metabolism , Liver/pathology , Male , Plant Extracts/chemistry , Plant Roots/chemistry , Protective Agents/chemistry , Pterocarpans/isolation & purification , Rats , Rats, Wistar , Silymarin/pharmacology , Superoxide Dismutase/blood
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