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1.
Microbiol Immunol ; 67(6): 293-302, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37067224

RESUMEN

Human herpesvirus 8 (HHV8; also known as Kaposi's sarcoma-associated herpesvirus [KSHV]) utilizes the viral E3 ubiquitin ligase family members K3 and K5 for immune evasion. Both K3 and K5 mediate the ubiquitination of host MHC class I (MHC-I) molecules, which play a key role in antigen presentation to cytotoxic T lymphocytes (CTLs). Because ubiquitinated MHC-I is immediately down-regulated from the cell surface, HHV8-infected cells can escape surveillance by CTLs. K3 and K5 have similar domain structures and topologies. They contain an N-terminal RINGv ubiquitin ligase domain, two transmembrane helices, and an intrinsically disordered cytoplasmic tail at the C-terminus. The cytoplasmic tail contains a membrane-proximal "conserved region" involved in ligase activity. On the other hand, the role of the membrane-distal region of the cytoplasmic tail, termed the "C-tail" in this study, remains unclear. Here, we demonstrate that the C-tail contributes to the protein expression of both K3 and K5. The C-tail-truncated K3 and K5 mutants were rapidly reduced in cells. The recombinant C-tail proteins bind to acidic lipids via a basic charge cluster located near the C-terminus of the C-tails. Similar to the C-tail-truncated mutants, the basic charge cluster-substituting mutants showed decreased protein expression of K3 and K5. These findings suggest that the basic charge cluster near the C-terminus of the cytoplasmic tail contributes to the molecular stability of K3 and K5.


Asunto(s)
Herpesvirus Humano 8 , Ubiquitina-Proteína Ligasas , Humanos , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/metabolismo , Antígenos de Histocompatibilidad Clase I/metabolismo , Ubiquitina/metabolismo
2.
Biochem J ; 479(20): 2261-2278, 2022 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-36305710

RESUMEN

Kaposi's sarcoma-associated herpesvirus (KSHV) is a carcinogenic virus that latently infects B cells and causes malignant tumors in immunocompromised patients. KSHV utilizes two viral E3 ubiquitin ligases, K3 and K5, in KSHV-infected cells to mediate the polyubiquitination-dependent down-regulation of several host membrane proteins involved in the immune system. Although K3 and K5 are members of the same family and have similar structural topologies, K3 and K5 have different substrate specificities. Hence, K5 may have a different substrate recognition mode than K3; however, the molecular basis of substrate recognition remains unclear. Here, we investigated the reason why human CD8α, which is known not to be a substrate for both K3 and K5, is not recognized by them, to obtain an understanding for molecular basis of substrate specificity. CD8α forms a disulfide-linked homodimer under experimental conditions to evaluate the viral ligase-mediated down-regulation. It is known that two interchain disulfide linkages in the stalk region between each CD8α monomer (Cys164-Cys164 and Cys181-Cys181) mediate homodimerization. When the interchain disulfide linkage of Cys181-Cys181 was eliminated, CD8α was down-regulated by K5 with a functional RING variant (RINGv) domain via polyubiquitination at the cytoplasmic tail. Aspartic acid, located at the stalk/transmembrane interface of CD8α, was essential for K5-mediated down-regulation of the CD8α mutant without a Cys181-Cys181 linkage. These results suggest that disulfide linkage near the stalk/transmembrane interface critically inhibits substrate targeting by K5. Accessibility to the extracellular juxtamembrane stalk region of membrane proteins may be important for substrate recognition by the viral ubiquitin ligase K5.


Asunto(s)
Herpesvirus Humano 8 , Proteínas Inmediatas-Precoces , Humanos , Ubiquitina/metabolismo , Proteínas Inmediatas-Precoces/metabolismo , Proteínas Virales/genética , Proteínas Virales/metabolismo , Proteínas de la Membrana/metabolismo , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Disulfuros/metabolismo
3.
J Gen Virol ; 102(11)2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34726593

RESUMEN

Kaposi's sarcoma-associated herpesvirus (KSHV) is an oncogenic etiological factor for Kaposi's sarcoma and primary effusion lymphoma in immunocompromised patients. KSHV utilizes two immune evasion E3 ubiquitin ligases, namely K3 and K5, to downregulate the expression of antigen-presenting molecules and ligands of natural killer (NK) cells in the host cells through an ubiquitin-dependent endocytic mechanism. This allows the infected cells to evade surveillance and elimination by cytotoxic lymphocytes and NK cells. The number of host cell molecular substrates reported for these ubiquitin ligases is limited. The identification of novel substrates for these ligases will aid in elucidating the mechanism underlying immune evasion of KSHV. This study demonstrated that K5 downregulated the cell surface expression of l-selectin, a C-type lectin-like adhesion receptor expressed in the lymphocytes. Tryptophan residue located at the centre of the E2-binding site in the K5 RINGv domain was essential to downregulate l-selectin expression. Additionally, the lysine residues located at the cytoplasmic tail of l-selectin were required for the K5-mediated downregulation of l-selectin. K5 promoted the degradation of l-selectin through polyubiquitination. These results suggest that K5 downregulates l-selectin expression on the cell surface by promoting polyubiquitination and ubiquitin-dependent endocytosis, which indicated that l-selectin is a novel substrate for K5. Additionally, K3 downregulated l-selectin expression. The findings of this study will aid in the elucidation of a novel immune evasion mechanism in KSHV.


Asunto(s)
Herpesvirus Humano 8/enzimología , Proteínas Inmediatas-Precoces/inmunología , Selectina L/genética , Sarcoma de Kaposi/genética , Sarcoma de Kaposi/virología , Ubiquitina-Proteína Ligasas/inmunología , Proteínas Virales/inmunología , Regulación hacia Abajo , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/inmunología , Interacciones Huésped-Patógeno , Humanos , Proteínas Inmediatas-Precoces/genética , Evasión Inmune , Células Asesinas Naturales/inmunología , Selectina L/inmunología , Sarcoma de Kaposi/inmunología , Ubiquitina-Proteína Ligasas/genética , Proteínas Virales/genética
4.
J Asian Nat Prod Res ; 18(2): 159-71, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26838028

RESUMEN

The plant, Cynomorium songaricum Rupr., is used as a traditional medicine in China and Mongolia. In the present study, two new water-soluble polysaccharides isolated from C. songaricum Rupr. were purified by successive Sephadex G-75 and G-50 column chromatographies and then characterized by high resolution NMR and IR spectroscopies. The molecular weights of two polysaccharides were determined by an aqueous GPC to be [Formula: see text] = 3.7 × 10(4) and 1.0 × 10(4), respectively. In addition, it was found that the polysaccharide with the larger molecular weight was an acidic polysaccharide. It was found that the iodine-starch reaction of both isolated polysaccharides was negative and the methylation analysis gave 2, 4, 6-tri-O-methyl alditol acetate as a main product. NMR and IR measurements and sugar analysis revealed that both polysaccharides had a (1 â†’ 3)-α-d-glucopyranosidic main chain with a small number of branches. After sulfation, the sulfated C. songaricum Rupr. polysaccharides were found to have a potent inhibitory effect on HIV infection of MT-4 cells at a 50% effective concentration of 0.3-0.4 µg/ml, a concentration that has almost the same high activity as standard dextran and curdlan sulfates, EC50 = 0.35 and 0.14 µg/ml, respectively. The 50% cytotoxic concentration was low, CC50>1000 µg/ml. In addition, the interaction between the sulfated polysaccharides and poly-l-lysine as a model protein compound was investigated by a surface plasmon resonance to reveal the anti-HIV mechanism.


Asunto(s)
Fármacos Anti-VIH/aislamiento & purificación , Fármacos Anti-VIH/farmacología , Cynomorium/química , Polisacáridos/aislamiento & purificación , Polisacáridos/farmacología , Fármacos Anti-VIH/química , China , Dextranos , Infecciones por VIH/tratamiento farmacológico , Humanos , Medicina Tradicional China , Medicina Tradicional Mongoliana , Modelos Biológicos , Estructura Molecular , Peso Molecular , Resonancia Magnética Nuclear Biomolecular , Tallos de la Planta/química , Polilisina/química , Polisacáridos/química , Solubilidad , Espectrofotometría Infrarroja , Agua
5.
J Oleo Sci ; 72(11): 1037-1048, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37914265

RESUMEN

Six optically active (Z)-7-decen-4-olide derivatives (1a-1f) were synthesized in 99% enantiomeric excess using diastereomeric resolution. The odour properties of the racemic and optically active 1a-1f were evaluated in terms of their orthonasal aromas. All of the stereoisomers had different odour characteristics and thresholds. Decen-4-olides (1a-1c) had a strong fruity note, whereas undecen-4-olide (1d and 1e) and dodecen-4-olide (1f) had a strong green note. For 7-alken-4-olides (1a, 1d, and 1f), the (R)-enantiomer had a lower odour threshold than the (S)-enantiomer. In contrast, no difference in the odour threshold was observed for the enantiomers of the 8-alken-4-olides (1b and 1e). Furthermore, the antimicrobial activity against Escherichia coli (E. coli; ATCC 25922) and Staphylococcus aureus (S. aureus; ATCC 29213) were investigated. Although the no differences in the antimicrobial activity of the stereoisomers was observed, 1d and 1e showed slight antimicrobial activity against E. coli, whereas only 1f showed antimicrobial activity against S. aureus. No antimicrobial activity was exhibited by (R)-1f, whereas (S)-1f exhibited strong antimicrobial activity.


Asunto(s)
Odorantes , Staphylococcus aureus , Escherichia coli
6.
Medicines (Basel) ; 8(10)2021 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-34677485

RESUMEN

Background: Very few studies of the antiviral potential of lignosulfonates have been published. With the aim of oral application, among various groups of natural products, the relative antiviral potency of lignosulfonate and its ability to rapidly inactivate viruses were investigated. Methods: As target cells, MT-4 cells in suspension and attached Vero cells were used for infections with human immunodeficiency virus (HIV) and human herpes simplex type-1 virus (HSV). Mock- or virus-infected cells were incubated for 3-5 days with various concentrations of test samples, and the viable cell number was determined with the MTT method. For the shorter exposure experiments, higher titers of HIV or HSV were exposed to test samples for 10 or 3 min, diluted to a normal multiplicity of infection (MOI), and applied to the cells. Antiviral activity was quantified by using the chemotherapy index. Results: In the long-exposure system, lignosulfonates showed comparable anti-HIV activity with those of AZT, ddC, and sulfated polysaccharides, and it exceeded those of hundreds of tannins and flavonoids. When the exposure time was shortened, the chemotherapeutic index of the lignosulfonates for HIV was increased 27-fold. At a physiological pH, lignosulfonate showed higher anti-HIV activity than commercial alkali-lignin, dealkali-lignin, and humic acid, possibly due to the higher solubility and purity. Conclusions: With their rapid virus-inactivation capabilities, lignosulfonates may be useful for the prevention or treatment of virally induced oral diseases.

7.
Medicines (Basel) ; 8(7)2021 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-34206186

RESUMEN

Background: Pyoktanin blue (PB) is used for staining tissues and cells, and it is applied in photodynamic therapy due to its potent bactericidal activity. However, clinical application of PB as an antiviral and antitumor agent has been limited due to its potent toxicity. For clinical application, the antitumor and antiviral activity as well as the neurotoxicity of PB were re-evaluated with a chemotherapeutic index. Methods: Tumor-specificity (TS) was determined by the ratio of CC50 against normal oral cells/oral squamous cell carcinoma (OSCC); neurotoxicity by that of normal oral/neuronal cells; antiviral activity by that of mock-infected/virus-infected cells; and potency-selectivity expression (PSE) by dividing TS by CC50 (OSCC). Results: Antitumor activity of PB (assessed by TS and PSE) was comparable with that of DXR and much higher than that of 5-FU and melphalan. PB induced caspase-3 activation and subG1 cell accumulation in an OSCC cell line (Ca9-22). PB and anticancer drugs showed comparable cytotoxicity against both neuronal cells and OSCC cell lines. PB showed no detectable anti-HIV/HSV activity, in contrast to reverse transferase inhibitors, sulfated glucans, and alkaline extract of leaves of S.P. Conclusions: PB showed first-class anticancer activity and neurotoxicity, suggesting the importance of establishing the safe treatment schedule.

8.
In Vivo ; 24(4): 543-51, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20668322

RESUMEN

BACKGROUND: In order to investigate the physiological role of lignin carbohydrate complex present in Lentinus edodes mycelia extract (LEM), this material was separated into seven fractions. MATERIALS AND METHODS: Three high molecular weight fractions (Frs. I-III) were prepared from the water extract by successive ethanol fractionation, dialysis and lyophilization. Four higher molecular weight fractions were prepared from the NaOH extract of the residue, followed by acid precipitation (Fr. IV) and stepwise ethanol precipitation (Frs. V-VII). RESULTS: All fractions showed higher anti-HIV activity than the water extract. Fr. IV showed the highest anti-HIV activity and most potently inhibited the NO production by LPS-stimulated mouse macrophage-like cells (RAW264.7, J774.1). ESR spectroscopy demonstrated that all fractions scavenged superoxide anion and hydroxyl radical. These properties are similar to those displayed by lignin carbohydrate complex, but not by glucans. HPLC analysis demonstrated the presence of lignin precursors, but not that of tannins, flavonoids and their related compounds. CONCLUSION: These results suggest a significant role of lignin-like substances in the expression of several important biological properties displayed by LEM.


Asunto(s)
Proteínas Fúngicas/química , Lignina/análisis , Lignina/farmacología , Polisacáridos/química , Animales , Fármacos Anti-VIH/aislamiento & purificación , Fármacos Anti-VIH/farmacología , Espectroscopía de Resonancia por Spin del Electrón , Depuradores de Radicales Libres/farmacología , VIH/efectos de los fármacos , Radical Hidroxilo/metabolismo , Lignina/aislamiento & purificación , Macrófagos/efectos de los fármacos , Macrófagos/fisiología , Ratones , Peso Molecular , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/metabolismo , Superóxidos/metabolismo
9.
Carbohydr Polym ; 239: 116022, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32414438

RESUMEN

To elucidate the role of long alkyl group in sulfated poly- and oligosaccharides on anti-HIV activity, the interaction between sulfated 3-O-octadecyl-(1→6)-α-d-glucopyranan with potent anti-HIV activity and liposomes with diameters of 58 ± 20 nm and 107 ± 28 nm as models of HIV were investigated. SPR measurements of sulfated 3-O-octadecyl-(1→6)-α-d-glucopyranans bearing 2.8 mol% of the octadecyl group and the liposome (diameter = 58 ± 20.0 nm and ζ=0 mV) resulted in an apparent association- ka = 6 × 105 1/M, a dissociation-rate kd = 4 × 10-4 1/s, and a dissociation constants KD = 8 × 10-10 M. The particle size of the sulfated 3-O-octadecyl-(1→6)-α-d-glucopyranan (67 ± 14 nm) measured by DLS increased to 104 ± 25 nm, whereas the ζ potential (-29 mV) was unchanged (-33 mV). For dextran sulfate without an alkyl group, no interaction was observed. These results suggest that the long octadecyl group penetrated into the liposome and sulfated glucopyranan was covered on the liposome to increase the anti-HIV activity. The 107 nm liposome exhibited similar results.


Asunto(s)
Glucanos/análisis , Sulfatos/análisis , Resonancia por Plasmón de Superficie , Conformación de Carbohidratos , Liposomas/análisis , Tamaño de la Partícula , Propiedades de Superficie
10.
Carbohydr Res ; 495: 108084, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32658833

RESUMEN

Three new spherical sulfated cellobiose-polylysine dendrimers of increasing generations bearing negatively charged sulfate groups were prepared by sulfating the corresponding cellobiose-polylysine dendrimers. The first, second, and third-generation derivatives exhibited potent anti-HIV activity with EC50 values of 3.7, 0.6, and 1.5 µg/mL, respectively, in constant to sulfated oligosaccharides with low anti-HIV activity, while the second-generation sulfated dendrimer was the most active. Surface plasmon resonance measurements with poly-l-lysine bearing positively charged amino acids as a model of the HIV surface glycoprotein gp120, indicated that the second-generation dendrimer had the lowest dissociation constant (KD = 1.86 × 10-12 M). Both the particle size and ζ potential increased in the presence of poly-l-lysine. It was proven that the moderate distance between the terminal sulfated cellobiose units in the second-generation dendrimer favored the high anti-HIV activity, owing to the electrostatic interactions developed due to the cluster effect.


Asunto(s)
Fármacos Anti-VIH/farmacología , Celobiosa/farmacología , Dendrímeros/farmacología , VIH-1/efectos de los fármacos , Polilisina/farmacología , Sulfatos/farmacología , Fármacos Anti-VIH/síntesis química , Fármacos Anti-VIH/química , Línea Celular Tumoral , Celobiosa/química , Dendrímeros/química , Humanos , Pruebas de Sensibilidad Microbiana , Conformación Molecular , Polilisina/química , Sulfatos/química
11.
J Bacteriol ; 191(13): 4166-79, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19395487

RESUMEN

Streptococcus sanguinis is an important cause of infective endocarditis. Previous studies have identified lipoproteins as virulence determinants in other streptococcal species. Using a bioinformatic approach, we identified 52 putative lipoprotein genes in S. sanguinis strain SK36 as well as genes encoding the lipoprotein-processing enzymes prolipoprotein diacylglyceryl transferase (lgt) and signal peptidase II (lspA). We employed a directed signature-tagged mutagenesis approach to systematically disrupt these genes and screen each mutant for the loss of virulence in an animal model of endocarditis. All mutants were viable. In competitive index assays, mutation of a putative phosphate transporter reduced in vivo competitiveness by 14-fold but also reduced in vitro viability by more than 20-fold. Mutations in lgt, lspA, or an uncharacterized lipoprotein gene reduced competitiveness by two- to threefold in the animal model and in broth culture. Mutation of ssaB, encoding a putative metal transporter, produced a similar effect in culture but reduced in vivo competiveness by >1,000-fold. [(3)H]palmitate labeling and Western blot analysis confirmed that the lgt mutant failed to acylate lipoproteins, that the lspA mutant had a general defect in lipoprotein cleavage, and that SsaB was processed differently in both mutants. These results indicate that the loss of a single lipoprotein, SsaB, dramatically reduces endocarditis virulence, whereas the loss of most other lipoproteins or of normal lipoprotein processing has no more than a minor effect on virulence.


Asunto(s)
Proteínas Bacterianas/fisiología , Endocarditis Bacteriana/microbiología , Lipoproteínas/fisiología , Streptococcus sanguis/patogenicidad , Animales , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Western Blotting , Biología Computacional , Electroforesis en Gel de Poliacrilamida , Prueba de Complementación Genética , Lipoproteínas/genética , Lipoproteínas/metabolismo , Modelos Genéticos , Conejos , Streptococcus sanguis/genética , Virulencia/genética
12.
Infect Immun ; 77(11): 4966-75, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19703977

RESUMEN

Streptococcus sanguinis is a member of the viridans group of streptococci and a leading cause of the life-threatening endovascular disease infective endocarditis. Initial contact with the cardiac infection site is likely mediated by S. sanguinis surface proteins. In an attempt to identify the proteins required for this crucial step in pathogenesis, we searched for surface-exposed, cell wall-anchored proteins encoded by S. sanguinis and then used a targeted signature-tagged mutagenesis (STM) approach to evaluate their contributions to virulence. Thirty-three predicted cell wall-anchored proteins were identified-a number much larger than those found in related species. The requirement of each cell wall-anchored protein for infective endocarditis was assessed in the rabbit model. It was found that no single cell wall-anchored protein was essential for the development of early infective endocarditis. STM screening was also employed for the evaluation of three predicted sortase transpeptidase enzymes, which mediate the cell surface presentation of cell wall-anchored proteins. The sortase A mutant exhibited a modest (approximately 2-fold) reduction in competitiveness, while the other two sortase mutants were indistinguishable from the parental strain. The combined results suggest that while cell wall-anchored proteins may play a role in S. sanguinis infective endocarditis, strategies designed to interfere with individual cell wall-anchored proteins or sortases would not be effective for disease prevention.


Asunto(s)
Proteínas Bacterianas/metabolismo , Pared Celular/metabolismo , Endocarditis Bacteriana/metabolismo , Infecciones Estreptocócicas/metabolismo , Streptococcus sanguis/patogenicidad , Aminoaciltransferasas/genética , Aminoaciltransferasas/metabolismo , Animales , Proteínas Bacterianas/genética , Pared Celular/genética , Cisteína Endopeptidasas/genética , Cisteína Endopeptidasas/metabolismo , Electroforesis en Gel de Poliacrilamida , Endocarditis Bacteriana/genética , Ensayo de Inmunoadsorción Enzimática , Mutagénesis Sitio-Dirigida , Mutación , Conejos , Infecciones Estreptocócicas/genética , Streptococcus sanguis/genética , Streptococcus sanguis/metabolismo
13.
Int J Biol Macromol ; 125: 909-914, 2019 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-30521896

RESUMEN

This study aims to quantitatively investigate the interaction between sulfated polysaccharides with potent anti-HIV activity, dextran and curdlan sulfates with negatively charged sulfate groups, and poly-L-lysine as a model protein and oligopeptides from a HIV surface glycoprotein gp120 with positively charged amino acids using surface plasmon resonance (SPR) and dynamic light scattering (DLS) to elucidate the anti-HIV mechanism of sulfated polysaccharides. The apparent association- (ka) and dissociation rate (kd) constants of dextran and curdlan sulfates against poly-L-lysine were ka = 6.92 × 104-2.17 × 106 1/Ms and kd = 4.29 × 10-5-2.22 × 10-4 1/s; these kinetic constants were dependent on the molecular weights and degree of sulfation of sulfated polysaccharides. For interaction, the three oligopeptides from the HIV gp120 were peptide A 297TRPNNNTRKRIRIQRGPGRA316 with several lysine (K) and arginine (R) in the V3 loop region, peptide B 493PLGVAPTKAKRRVVQREKR511 with several K and R in the C-terminus region, and oligopeptide C 362KQSSGGDPEIVTHSFNCGG380 with few basic amino acids in the CD4 binding domain. Sulfated polysaccharides exhibited strong interaction against oligopeptides A and B, (ka = 5.48 × 104-2.96 × 106 1/Ms. and kd = 1.74 × 10-4-6.24 × 10-3 1/s), no interaction was noted against oligopeptide C. Moreover, the particle size and zeta potential by DLS indicated the interaction between sulfated polysaccharides and oligopeptides A and B, suggesting the anti-HIV mechanism of sulfated polysaccharides to be the electrostatic interaction of negatively charged sulfated polysaccharides and HIV at the positively charged amino acid regions.


Asunto(s)
Oligopéptidos/química , Péptidos/química , Polisacáridos/química , Sulfatos/química , Dextranos/química , Proteína gp120 de Envoltorio del VIH/química , Peso Molecular , Polilisina/química , Resonancia por Plasmón de Superficie/métodos , beta-Glucanos/química
14.
In Vivo ; 22(4): 471-6, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18712174

RESUMEN

Sasa senanensis Rehder extract (SE) showed slightly higher cytotoxicity against human squamous cell carcinoma cell lines and human glioblastoma cell lines, as compared with human oral normal cells (gingival fibroblast, pulp cell, periodontal ligament fibroblast), and was more cytotoxic to human myelogenous and T-cell leukemia cell lines. SE showed a bacteriostatic effect on Fusobacterium nucleatum and Prevotella intermedia, but almost completely eliminated hydrogen sulfide (H2S) and methyl mercaptan (CH3SH) produced by these bacteria. SE protected human T-cell leukemia MT-4 cells from the cytopathic effect of human immunodeficiency virus (HIV) infection, and its anti-HIV activity was much higher than that of tannins and flavonoids, comparable with that of natural and synthetic lignins. SE also protected the MDCK cells from the cytopathic effect of influenza virus infection. SE synergistically enhanced the superoxide anion and hydroxyl radical-scavenging activity of vitamin C. The present study suggests the functionality of SE as a complementary alternative medicine.


Asunto(s)
Antibacterianos/farmacología , Antivirales/farmacología , Ácido Ascórbico/metabolismo , Ácido Ascórbico/farmacología , Extractos Vegetales/farmacología , Sasa/metabolismo , Animales , Fármacos Anti-VIH/farmacología , Línea Celular , Línea Celular Tumoral , Perros , Sinergismo Farmacológico , Fibroblastos/metabolismo , Depuradores de Radicales Libres/farmacología , Infecciones por VIH/prevención & control , Humanos
15.
In Vivo ; 22(3): 327-32, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18610744

RESUMEN

Cacao husk lignin fractions, prepared by acid precipitation and 50% ethanol precipitation showed unexpectedly higher anti-human immunodeficiency virus (HIV) activity, as compared with the corresponding fractions from the cacao mass, amounting to the level comparable with that of popular anti-HIV compounds. The cacao husk lignin fractions also showed anti-influenza virus activity, but did not show antibacterial activity. The cacao husk lignin fractions synergistically enhanced the superoxide anion and hydroxyl radical scavenging activity of vitamin C. The cacao husk lignin fractions stimulated nitric oxide generation by mouse macrophage-like cells, to a level higher than that attained by lipopolysaccharide (LPS). The present study suggests the functionality of cacao husk lignin fractions as complementary alternative medicine.


Asunto(s)
Fármacos Anti-VIH/farmacología , Ácido Ascórbico/farmacología , Cacao/química , Lignina/farmacología , Animales , Línea Celular , Sinergismo Farmacológico , Radicales Libres/química , Humanos , Lignina/aislamiento & purificación , Activación de Macrófagos/efectos de los fármacos , Ratones , Extractos Vegetales/química , Extractos Vegetales/farmacología
16.
Medicines (Basel) ; 5(4)2018 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-30514000

RESUMEN

Background: The genera Abiotrophia and Granulicatella, previously known as nutritionally variant streptococci (NVS), are fastidious bacteria requiring vitamin B6 analogs for growth. They are members of human normal oral microbiota, and are supposed to be one of the important pathogens for so-called "culture-negative" endocarditis. Methods: The type strains and oral isolates identified, by using both phenotypic profiles and the DNA⁻DNA hybridization method, were examined for susceptibilities to 15 antimicrobial agents including penicillin (benzylpenicillin, ampicillin, amoxicillin, and piperacillin), cephem (cefazolin, ceftazidime, ceftriaxone, and cefaclor), carbapenem (imipenem), aminoglycoside (gentamicin), macrolide (erythromycin), quinolone (ciprofloxacin), tetracycline (minocycline), glycopeptide (vancomycin), and trimethoprim-sulfamethoxazole complex. The minimum inhibitory concentration and susceptibility criterion were determined, according to the consensus guideline from the Clinical and Laboratory Standards Institute. Results: Isolates of Abiotrophia defectiva were susceptible to ampicillin, amoxicillin ceftriaxone, cefaclor, imipenem, ciprofloxacin, and vancomycin. Isolates of Granulicatella adiacens were mostly susceptible to benzylpenicillin, ampicillin, amoxicillin, cefazolin, ceftriaxone, imipenem, minocycline, and vancomycin. The susceptibility profile of Granulicatella elegans was similar to that of G. adiacens, and the susceptibility rate was higher than that of G. adiacens. Conclusions: Although Abiotrophia and Granulicatella strains are hardly distinguishable by their phenotypic characteristics, their susceptibility profiles to the antimicrobial agents were different among the species. Species-related differences in susceptibility of antibiotics should be considered in the clinical treatment for NVS related infections.

17.
In Vivo ; 21(3): 499-505, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17591360

RESUMEN

Anti-stress and anti-HIV activity of mulberry juice were separated by centrifugation. The anti-stress activity was enriched in the supernatant fraction whereas the anti-HIV activity in the precipitate fraction. Oral administration of the supernatant fraction significantly reduced the elevated plasma level of lipid peroxide in mice loaded with water immersion restraint stress. The kinetic study revealed that the anti-stress activity was maintained for 4 hours after cessation of the administration of mulberry juice. The lignin fraction in the precipitate fraction scavenged superoxide and hydroxyl radicals more efficiently than other fractions, in a synergistic fashion with sodium ascorbate. Anti-HIV activity of mulberry juice was concentrated in the lignin fraction, whereas blueberry juice, which has no precipitating fibrous materials, did not show anti-HIV activity. The present study suggests the functionality of mulberry juice as an alternative medicine.


Asunto(s)
Fármacos Anti-VIH/farmacología , Ácido Ascórbico/farmacología , Depuradores de Radicales Libres/farmacología , VIH-1/efectos de los fármacos , Morus/química , Extractos Vegetales/farmacología , Estrés Psicológico/tratamiento farmacológico , Animales , Línea Celular Tumoral , Fraccionamiento Químico , Sinergismo Farmacológico , VIH-1/fisiología , Humanos , Radical Hidroxilo/metabolismo , Peróxidos Lipídicos/sangre , Ratones , Ratones Endogámicos BALB C , Fitoterapia , Extractos Vegetales/química , Estrés Psicológico/sangre , Superóxidos/metabolismo , Replicación Viral/efectos de los fármacos
18.
Acta Biomater ; 64: 116-125, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29037895

RESUMEN

Most peptide drugs have short half-lives, necessitating frequent injections that may induce skin sensitivity reactions; therefore, versatile prolonged-release delivery platforms are urgently needed. Here, we focused on an oxidatively and thermally responsive recombinant elastin-like polypeptide with periodic cysteine residues (cELP), which can rapidly and reversibly form a disulfide cross-linked network in which peptide can be physically incorporated. As a model for proof of concept, we used enfuvirtide, an antiretroviral fusion-inhibitor peptide approved for treatment of human immunodeficiency virus (HIV) infection. cELP was mixed with enfuvirtide and a small amount of hydrogen peroxide (to promote cross-linking), and the soluble mixture was injected subcutaneously. The oxidative cross-linking generates a network structure, causing the mixture to form a hydrogel in situ that serves as an enfuvirtide depot. We fabricated a series of enfuvirtide-containing hydrogels and examined their stability, enfuvirtide-releasing profile and anti-HIV potency in vitro. Among them, hydrophobic cELP hydrogel provided effective concentrations of enfuvirtide in blood of rats for up to 8 h, and the initial concentration peak was suppressed compared with that after injection of enfuvirtide alone. cELP hydrogels should be readily adaptable as platforms to provide effective depot systems for delivery of other anti-HIV peptides besides enfuvirtide. STATEMENT OF SIGNIFICANCE: In this paper, we present an anti-HIV peptide delivery system using oxidatively and thermally responsive polypeptides that contain multiple periodic cysteine residues as an injectable biomaterial capable of in situ self-gelation, and we demonstrate its utility as an injectable depot capable of sustained release of anti-HIV peptides. The novelty of this work stems from the platform employed to provide the depot encapsulating the peptide drugs (without chemical conjugation), which consists of rationally designed, genetically engineered polypeptides that enable the release rate of the peptide drugs to be precisely controlled.


Asunto(s)
Implantes de Medicamentos , Elastina , Proteína gp41 de Envoltorio del VIH , Infecciones por VIH/tratamiento farmacológico , VIH-1 , Hidrogeles , Fragmentos de Péptidos , Animales , Línea Celular , Reactivos de Enlaces Cruzados/química , Implantes de Medicamentos/síntesis química , Implantes de Medicamentos/química , Implantes de Medicamentos/farmacocinética , Implantes de Medicamentos/farmacología , Elastina/farmacocinética , Elastina/farmacología , Enfuvirtida , Proteína gp41 de Envoltorio del VIH/química , Proteína gp41 de Envoltorio del VIH/farmacocinética , Proteína gp41 de Envoltorio del VIH/farmacología , Infecciones por VIH/metabolismo , Humanos , Hidrogeles/síntesis química , Hidrogeles/química , Hidrogeles/farmacocinética , Hidrogeles/farmacología , Peróxido de Hidrógeno/química , Masculino , Fragmentos de Péptidos/química , Fragmentos de Péptidos/farmacocinética , Fragmentos de Péptidos/farmacología , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/farmacología
19.
Nutrients ; 9(12)2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-29194366

RESUMEN

Prebiotics and probiotics strongly impact the gut ecosystem by changing the composition and/or metabolism of the microbiota to improve the health of the host. However, the composition of the microbiota constantly changes due to the intake of daily diet. This shift in the microbiota composition has a considerable impact; however, non-pre/probiotic foods that have a low impact are ignored because of the lack of a highly sensitive evaluation method. We performed comprehensive acquisition of data using existing measurements (nuclear magnetic resonance, next-generation DNA sequencing, and inductively coupled plasma-optical emission spectroscopy) and analyses based on a combination of machine learning and network visualization, which extracted important factors by the Random Forest approach, and applied these factors to a network module. We used two pteridophytes, Pteridium aquilinum and Matteuccia struthiopteris, for the representative daily diet. This novel analytical method could detect the impact of a small but significant shift associated with Matteuccia struthiopteris but not Pteridium aquilinum intake, using the functional network module. In this study, we proposed a novel method that is useful to explore a new valuable food to improve the health of the host as pre/probiotics.


Asunto(s)
Helechos/química , Alimentos , Tracto Gastrointestinal/fisiología , Aprendizaje Automático , Modelos Biológicos , Humanos , Masculino , Microbiota , Prebióticos , Probióticos
20.
Anticancer Res ; 37(11): 6161-6168, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-29061797

RESUMEN

BACKGROUND/AIM: Eleven piperic acid esters were subjected to quantitative structure-activity relationship (QSAR) analysis based on their cytotoxicity and tumor-specificity, in order to find their new biological activities. MATERIALS AND METHODS: Cytotoxicity against four human oral squamous cell carcinoma cell lines and three oral normal mesenchymal cells was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. Tumor specificity (TS) was evaluated by the ratio of the mean 50% cytotoxic concentration (CC50) against normal cells to that against tumor cell lines. Potency-selectivity expression (PSE) value was calculated by dividing the TS value by CC50 against tumor cells. Apoptosis markers were detected by western blot analysis. Physicochemical, structural and quantum-chemical parameters were calculated based on the conformations optimized by force-field minimization. RESULTS: One phenylmethyl ester and five phenylethyl esters showed relatively higher cytotoxicity and tumor specificity, that were significantly modified by introduction of hydroxyl and methoxy groups. On the other hand, phenylpropyl ester, phenylbutyl ester and decyl ester were essentially inactive. (2E,4E)-5-(3,4-methylenedioxyphenyl)-2,4-pentadienoic acid 2-(3,4-dihydroxyphenyl)ethyl ester [4] had the highest TS and PSE values. This compound also stimulated the cleavage of caspase-3, suggesting the induction of apoptosis. TS values were correlated with molecular size, ionization potential, molecular shape, ionization potential and electronegativity. None of the compounds had any anti-HIV activity. CONCLUSION: Chemical modification of the lead compound may be a potential choice for designing a new type of anticancer drugs.


Asunto(s)
Fármacos Anti-VIH/farmacología , Apoptosis/efectos de los fármacos , Carcinoma de Células Escamosas/tratamiento farmacológico , Ésteres/farmacología , Ácidos Grasos Insaturados/química , VIH/efectos de los fármacos , Neoplasias de la Boca/tratamiento farmacológico , Antineoplásicos/farmacología , Carcinoma de Células Escamosas/patología , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Niño , Femenino , Humanos , Estructura Molecular , Neoplasias de la Boca/patología , Relación Estructura-Actividad Cuantitativa
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