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1.
Int J Biol Macromol ; 269(Pt 1): 131761, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38663705

RÉSUMÉ

Lepidium meyenii Walp., also known as the "Peruvian national treasure", is a popular functional food in the daily lives of Peruvian people due to its bioactive with main polysaccharides. However, studies on polysaccharides isolated from Lepidium meyenii were few. Two new highly heterogeneous polysaccharides, MCP-1a and MCP-2b, were isolated and purified from the tuber of Lepidium meyenii. The structure characterization revealed that MCP-1a primarily consisted of D-Glc and had a molecular weight of 6.6 kDa. Its backbone was composed of 1,4,6-α-D-Glc, while branches feature T-α-L-Ara, 1,5-α-L-Ara, and T-α-D-Glc attached to the O-6 positions. MCP-2b was a rare arabinogalactan with a molecular weight of 49.4 kDa. Interestingly, the backbone of MCP-2b was composed of 1,6-ß-D-Gal, 1,3,6-ß-D-Gal with a few 1,3-ß-D-GlcpA-4-OMe units inserted. Side chains of MCP-2b were mainly composed of 1,3-ß-D-Gal, T-ß-D-Gal, T-α-L-Ara, 1,5-α-L-Ara, with trace amounts of 1,4-ß-D-Glc and T-ß-D-Glc. The bioactivity assay results revealed that MCP-1a and MCP-2b increased the release of NO, IL-1ß, TNF-α, and IL-6 from RAW 264.7 cells at concentrations ranging from 50 µg/mL to 400 µg/mL. Furthermore, MCP-1a and MCP-2b could promote the expression of key transcription factors (IκB-α, p-IκB-α, p65, and p-p65) in the NF-κB pathway, indicating that MCP-1a and MCP-2b had potential immunomodulatory activities.


Sujet(s)
Lepidium , Facteur de transcription NF-kappa B , Polyosides , Transduction du signal , Lepidium/composition chimique , Polyosides/pharmacologie , Polyosides/composition chimique , Polyosides/isolement et purification , Souris , Facteur de transcription NF-kappa B/métabolisme , Animaux , Transduction du signal/effets des médicaments et des substances chimiques , Cellules RAW 264.7 , Facteurs immunologiques/pharmacologie , Facteurs immunologiques/composition chimique , Facteurs immunologiques/isolement et purification , Masse moléculaire , Cytokines/métabolisme
2.
Nat Prod Bioprospect ; 13(1): 18, 2023 Jun 06.
Article de Anglais | MEDLINE | ID: mdl-37278859

RÉSUMÉ

Four polysaccharides (MCPa, MCPb, MCPc, MCPd) were obtained from Lepidium meyenii Walp. Their structures were characterized by chemical and instrumental methods including total sugar, uronic acid and protein content determination, UV, IR and NMR spectroscopy, as well as monosaccharide composition determination and methylation analyses. Four polysaccharides were a group of glucans with different molecular weights ranging from 3.12 to 14.4 kDa, and shared a similar backbone chain consisting of (1→4)-glucose linkages with branches attached to C-3 and C-6. Furthermore, bioactivity assay showed that MCPs had concentration-dependent inhibitory activity on α-glucosidase. MCPb (Mw = 10.1 kDa) and MCPc (Mw = 5.62 kDa) with moderate molecular weights exhibited higher inhibitory activity compared with MCPa and MCPd.

3.
Int Immunopharmacol ; 114: 109606, 2023 Jan.
Article de Anglais | MEDLINE | ID: mdl-36700776

RÉSUMÉ

Osteoarthritis (OA) is a degenerative and progressive disease that affects joints. Pathologically, it is characterized by oxidative stress-mediated excessive chondrocyte apoptosis and mitochondrial dysfunction. Fibroblast growth factor 9 (FGF9) has been shown to exert antioxidant effects and prevent degenerative diseases by activating ERK-related signaling pathways. However, the mechanism of FGF9 in the pathogenesis of OA and its relationship with anti-oxidative stress and related pathways are unclear. In this study, mice with medial meniscus instability (DMM) were used as the in vivo model whereas TBHP-induced chondrocytes served as the in vitro model to explore the mechanism underlying the effects of FGF9 in OA and its association with anti-oxidative stress. Results showed that FGF9 reduced oxidative stress, apoptosis, and mitochondrial dysfunction in TBHP-treated chondrocytes and promoted the nuclear translocation of Nrf2 to activate the Nrf2/HO1 signaling pathway. Interestingly, silencing the Nrf2 gene or blocking the ERK signaling pathway abolished the antioxidant effects of FGF9. FGF9 treatment reduced joint space narrowing, cartilage ossification, and synovial thickening in the DMM model mice. In conclusion, the present findings demonstrate that FGF9 can inhibit TBHP-induced oxidative stress in chondrocytes through the ERK and Nrf2-HO1 signaling pathways and prevent the progression of OA in vivo.


Sujet(s)
Antioxydants , Arthrose , Animaux , Souris , Antioxydants/pharmacologie , Antioxydants/usage thérapeutique , Antioxydants/métabolisme , Apoptose , Chondrocytes , Facteur de croissance fibroblastique de type 9/métabolisme , Facteur de croissance fibroblastique de type 9/pharmacologie , Facteur-2 apparenté à NF-E2/métabolisme , Arthrose/métabolisme , Stress oxydatif , Transduction du signal , Système de signalisation des MAP kinases
4.
J Agric Food Chem ; 68(26): 6977-6986, 2020 Jul 01.
Article de Anglais | MEDLINE | ID: mdl-32502339

RÉSUMÉ

Six new pentacyclic triterpenoid saponins, centelloside F (1), centelloside G (2), 11-oxo-asiaticoside B (3), 11-oxo-madecassoside (4), 11(ß)-methoxy asiaticoside B (5), and 11(ß)-methoxy madecassoside (6), along with seven known ones, asiaticoside (7), asiaticoside B (8), madecassoside (9), centellasaponin A (10), isoasiaticoside (11), scheffoleoside A (12), and centelloside E (13), were separated from the 80% MeOH extract of the whole plant of Centella asiatica, which has been used as a medicinal plant and is now commercially available as a diatery supplement in many countries. Compounds 1 and 2, 3 and 4, and 5 and 6 are three pairs of isomers with oleanane- or ursane-type triterpenes as aglycones. The chemical structures of the new triterpene saponins were fully characterized by extensive analysis of their nuclear magnetic resonance and high-resolution electrospray ionization mass spectrometry data. The protective effects of compounds 1-13 on PC12 cells induced by 6-OHDA were screened, and compound 3 displayed the best neuroprotective effect, with 91.75% cell viability at the concentration of 100 µM. Moreover, compound 3 also attenuated cell apoptosis and increased the mRNA expression of antioxidant enzymes, including superoxide dismutase and catalase. Additionally, compound 3 activated the phosphatidylinositol 3-kinase/Akt pathway, including PDK1, Akt, and GSK-3ß. These findings suggested that triterpene saponins from C. asiatica were worthy of further biological research to develop new neuroprotective agents.


Sujet(s)
Centella/composition chimique , Neuroprotecteurs/pharmacologie , Acide oléanolique/analogues et dérivés , Extraits de plantes/composition chimique , Triterpènes/pharmacologie , Animaux , Apoptose/effets des médicaments et des substances chimiques , Catalase/métabolisme , Survie cellulaire/effets des médicaments et des substances chimiques , Glycogen synthase kinase 3 beta/métabolisme , Neurones/cytologie , Neurones/effets des médicaments et des substances chimiques , Neurones/métabolisme , Neuroprotecteurs/composition chimique , Acide oléanolique/composition chimique , Acide oléanolique/pharmacologie , Cellules PC12 , Extraits de plantes/pharmacologie , Rats , Superoxide dismutase/métabolisme , Triterpènes/composition chimique
6.
Phytochemistry ; 147: 125-131, 2018 Mar.
Article de Anglais | MEDLINE | ID: mdl-29306798

RÉSUMÉ

The investigation of the fruits of Solanum nigrum led to the isolation of four previously undescribed steroidal alkaloids, named solanine A, 7α-OH khasianine, 7α-OH solamargine and 7α-OH solasonine, together with six known ones. The structures of the isolated compounds were elucidated unambiguously by spectroscopic data analyses and chemical methods. Solanine A represents an unusual steroidal alkaloid with an unprecedented 6/5/6/5/5/6 hexacyclic ring system, and its structure was confirmed by X-ray single crystal diffraction analysis. Compounds 2-4 were rare naturally occurring steroidal alkaloid glycosides bearing a hydroxyl group at C-7 position. Solanine A showed the most potent inhibitory activity against the LPS-induced NO production in murine RAW264.7 macrophages with an IC50 value of 3.85 ± 0.71 µM and significant cytotoxicity against MGC803, HepG2 and SW480 cancer cell lines with IC50 values of 6.00 ± 0.52 µM, 9.25 ± 0.49 µM and 6.23 ± 0.26 µM, respectively.


Sujet(s)
Alcaloïdes/pharmacologie , Antinéoplasiques d'origine végétale/pharmacologie , Médicaments issus de plantes chinoises/composition chimique , Fruit/composition chimique , Solanum nigrum/composition chimique , Stéroïdes/pharmacologie , Alcaloïdes/composition chimique , Alcaloïdes/isolement et purification , Animaux , Antinéoplasiques d'origine végétale/composition chimique , Antinéoplasiques d'origine végétale/isolement et purification , Lignée cellulaire tumorale , Prolifération cellulaire/effets des médicaments et des substances chimiques , Survie cellulaire/effets des médicaments et des substances chimiques , Relation dose-effet des médicaments , Tests de criblage d'agents antitumoraux , Médicaments issus de plantes chinoises/isolement et purification , Médicaments issus de plantes chinoises/pharmacologie , Humains , Lipopolysaccharides/antagonistes et inhibiteurs , Lipopolysaccharides/pharmacologie , Macrophages/effets des médicaments et des substances chimiques , Macrophages/métabolisme , Médecine traditionnelle chinoise , Souris , Structure moléculaire , Monoxyde d'azote/antagonistes et inhibiteurs , Monoxyde d'azote/biosynthèse , Cellules RAW 264.7 , Stéroïdes/composition chimique , Stéroïdes/isolement et purification , Relation structure-activité
7.
Disaster Med Public Health Prep ; 12(1): 109-114, 2018 02.
Article de Anglais | MEDLINE | ID: mdl-28260561

RÉSUMÉ

This article outlines the evolution of a rescue team in responding to adenovirus prevention with a deployable field hospital. The local governments mobilized a shelter hospital and a rescue team consisting of 59 members to assist with rescue and response efforts after an epidemic outbreak of adenovirus. We describe and evaluate the challenges of preparing for deployment, field hospital maintenance, treatment mode, and primary treatment methods. The field hospital established at the rescue scene consisted of a medical command vehicle, a computed tomography shelter, an X-ray shelter, a special laboratory shelter, an oxygen and electricity supply vehicle, and epidemic prevention and protection equipment. The rescue team comprised paramedics, physicians, X-ray technicians, respiratory therapists, and logistical personnel. In 22 days, more than 3000 patients with suspected adenovirus infection underwent initial examinations. All patients were properly treated, and no deaths occurred. After emergency measures were implemented, the spread of adenovirus was eventually controlled. An emergency involving infectious diseases in less-developed regions demands the rapid development of a field facility with specialized medical personnel when local hospital facilities are either unavailable or unusable. An appropriate and detailed prearranged action plan is important for infectious diseases prevention. (Disaster Med Public Health Preparedness. 2018;12:109-114).


Sujet(s)
Infections à Adenoviridae/thérapie , Protection civile/normes , Hôpitaux/tendances , Facteurs temps , Chine , Protection civile/méthodes , Protection civile/tendances , Épidémies de maladies/prévention et contrôle , Conception et construction de locaux/normes , Humains , Isolement du patient/méthodes , Santé publique/méthodes , Tomodensitométrie/méthodes
8.
Disaster Med Public Health Prep ; 12(4): 427-430, 2018 08.
Article de Anglais | MEDLINE | ID: mdl-27645610

RÉSUMÉ

OBJECTIVE: Human adenovirus type 55 (HAdV-55) has recently caused multiple outbreaks. This study examined polymorphisms in CD46 to determine their involvement in HAdV-55 infection. METHODS: A total of 214 study subjects infected with HAdV-55 were included in our study. The study subjects were divided into those with silent infections (n=91), minor infections (n=85), and severe infections (n=38). Ten single nucleotide polymorphisms (SNPs) from CD46 were examined. RESULTS: Compared with the AA genotype, the TT genotype at rs2724385 (CD46, A/T) was associated with a protective effect against disease occurrence, with an odds ratio (95% confidence interval) of 0.20 (0.04-0.97) (P=0.038). There were no significant differences between the patients with minor and severe infection and those who had silent HAdV-55 infection in the other CD46 SNPs. We next compared the polymorphisms of these genes according to disease severity in HAdV-55-infected patients with clinical symptoms. The results showed that there were no significant differences between minor infections and severe infections. CONCLUSIONS: Our results suggested that the CD46 SNP at rs2724385 is associated with the occurrence of disease in HAdV-55-infected patients. A much larger number of samples is required to understand the role of CD46 polymorphisms in the occurrence and progression of infection by HAdV-55. (Disaster Med Public Health Preparedness. 2018;12:427-430).


Sujet(s)
Infections à Adenoviridae/génétique , Antigènes CD46/analyse , Polymorphisme génétique/génétique , Adenoviridae/pathogénicité , Infections à Adenoviridae/sang , Adolescent , Asiatiques/ethnologie , Asiatiques/statistiques et données numériques , Chine , Épidémies de maladies , Humains , Mâle , Antigènes CD46/sang , Polymorphisme génétique/immunologie , Jeune adulte
9.
Fitoterapia ; 118: 6-12, 2017 Apr.
Article de Anglais | MEDLINE | ID: mdl-28214554

RÉSUMÉ

Four new C21 steroidal glycosides (1-4), named perisepiumosides FI (1-4) together with six known steroidal glycosides (5-10) and four oligosaccharides (11-14), were isolated from the root bark of Periploca sepium. Their structures were characterized on the basis of 1D and 2D-NMR spectroscopic data as well as HR-ESI-MS analysis. The evaluation of inhibition activity against human A-549 and HepG2 cell lines indicated that compounds 2, 8, 10 and 13 showed different levels of cytotoxic activities with IC50 values ranging from 0.61 to 7.86µM.


Sujet(s)
Hétérosides/composition chimique , Oligosaccharides/composition chimique , Periploca/composition chimique , Racines de plante/composition chimique , Cellules A549 , Hétérosides/isolement et purification , Cellules HepG2 , Humains , Structure moléculaire , Oligosaccharides/isolement et purification
10.
Int J Dermatol ; 49(12): 1429-31, 2010 Dec.
Article de Anglais | MEDLINE | ID: mdl-21091681

RÉSUMÉ

A case of a 28 year-old Chinese male who presented with a rapidly growing tumor within a nevus sebaceous on his right cheek. The tumor was excised and immunohistochemical analysis and histology were consistent with spindle-cell squamous cell carcinoma. To the best of our knowledge, it is the first report of cutaneous spindle-cell squamous cell carcinoma developing in nevus sebaceous in the English literature. This report highlights the importance of early excision of any nevus sebaceous with a history of change.


Sujet(s)
Carcinome épidermoïde/complications , Carcinome épidermoïde/anatomopathologie , Naevus sébacé de Jadassohn/complications , Tumeurs cutanées/complications , Tumeurs cutanées/anatomopathologie , Adulte , Carcinome épidermoïde/chirurgie , Joue/anatomopathologie , Humains , Mâle , Tumeurs cutanées/chirurgie
12.
Chin Med J (Engl) ; 120(11): 975-80, 2007 Jun 05.
Article de Anglais | MEDLINE | ID: mdl-17624265

RÉSUMÉ

BACKGROUND: Candida albicans (C. albicans) infection, often occurring in genital candidiasis, has increased dramatically recently. Developing an efficient C. albicans typing method may contribute to understanding its epidemiological characteristics and guiding efficient treatment. We used rapid microsatellite genotyping assay for interstrain differentiation of C. albicans isolates and explored some characteristics of its spread. METHODS: DNA was extracted from C. albicans isolates from gentalia, recta and mouths of 39 female cases and 27 male cases of genital candidiasis. Three fluorescent primers for the microsatellite markers in conserved genes (CDC3, EF3 and HIS3) of C. albicans were used to amplify the isolates DNA by PCR. Fluorescent signals were read with an automatic sequencer and analyzed with GeneScan software. RESULTS: Analysis of the three microsatellites markers showed 18 gene allelic associations in genital C. albicans infected patients: 10 allelic associations in female and 11 allelic associations in male, of which 3 allelic associations shared by both genders covered 71% of infections. The most dominant allele association of pathogenic strains for both genders was 116:124, 122:131, 160:200 that covered about 50% of infection. Gentalia and recta shared the same strains in 80% of female patients, but in only 3.8% of male patients. There were 2.7% female patients, but no males, with same strain in both gentalia and mouths. Five of seven genital C. albicans infected couples had the same allelic associations of which 4 were the dominant pathogenic C. albicans susceptible for both genders. CONCLUSIONS: The predominant allelic association of the pathogenic strain in genital C. albicans infection is 116:124, 122:131, 160:200. Vaginal pathogenic strains are probably maintained from the rectal reservoir. Pathogenic strains of male patients are probably from frequent sexual intercourse. The aggressiveness of some strains varies with gender.


Sujet(s)
Candida albicans/génétique , Candidose vulvovaginale/diagnostic , Candidose/diagnostic , Maladies de l'appareil génital mâle/diagnostic , Répétitions microsatellites , Adulte , Candida albicans/classification , Femelle , Génotype , Humains , Mâle , Rectum/microbiologie , Sensibilité et spécificité , Langue/microbiologie
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