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1.
Nutrients ; 14(1)2021 Dec 23.
Article de Anglais | MEDLINE | ID: mdl-35010924

RÉSUMÉ

Non-alcoholic steatohepatitis (NASH) can cause liver cirrhosis and hepatocellular carcinoma (HCC), with cases increasing worldwide. To reduce the incidence of liver cirrhosis and HCC, NASH is targeted for the development of treatments, along with viral hepatitis and alcoholic hepatitis. Lactoferrin (LF) has antioxidant, anti-cancer, and anti-inflammatory activities. However, whether LF affects NASH and fibrosis remains unelucidated. We aimed to clarify the chemopreventive effect of LF on NASH progression. We used a NASH model with metabolic syndrome established using connexin 32 (Cx32) dominant negative transgenic (Cx32ΔTg) rats. Cx32ΔTg rats (7 weeks old) were fed a high-fat diet and intraperitoneally injected with dimethylnitrosamine (DMN). Rats were divided into three groups for LF treatment at 0, 100, or 500 mg/kg/day for 17 weeks. Lactoferrin significantly protected steatosis and lobular inflammation in Cx32ΔTg rat livers and attenuated bridging fibrosis or liver cirrhosis induced by DMN. By quantitative RT-PCR, LF significantly down-regulated inflammatory (Tnf-α, Il-6, Il-18, and Il-1ß) and fibrosis-related (Tgf-ß1, Timp2, and Col1a1) cytokine mRNAs. Phosphorylated nuclear factor (NF)-κB protein decreased in response to LF, while phosphorylated JNK protein was unaffected. These results indicate that LF might act as a chemopreventive agent to prevent hepatic injury, inflammation, and fibrosis in NASH via NF-κB inactivation.


Sujet(s)
Lactoferrine/pharmacologie , Cirrhose du foie/prévention et contrôle , Facteur de transcription NF-kappa B/métabolisme , Stéatose hépatique non alcoolique/traitement médicamenteux , Animaux , Anticarcinogènes/pharmacologie , Carcinogenèse/effets des médicaments et des substances chimiques , Carcinome hépatocellulaire/traitement médicamenteux , Connexines/métabolisme , Cytokines/métabolisme , N-Méthyl-N-nitroso-méthanamine/effets indésirables , Fibrose/prévention et contrôle , Lactoferrine/administration et posologie , Foie/traumatismes , Tumeurs du foie/traitement médicamenteux , Mâle , Stéatose hépatique non alcoolique/métabolisme , Rats , Facteur de croissance transformant bêta-1/métabolisme , Facteur de nécrose tumorale alpha/métabolisme ,
2.
Biochimie ; 91(1): 52-7, 2009 Jan.
Article de Anglais | MEDLINE | ID: mdl-18585434

RÉSUMÉ

Lactoferrin (LF) was identified as a milk protein in 1960. Large-scale manufacturing of bovine LF (bLF) was established more than 20 years ago. Using this commercially available material, research for bLF applications has advanced from basic studies to clinical studies, and bLF has been applied to commercial food products for the last 25 years. During this period, it was found that LF is digested by gastric pepsin to generate a multi-potent peptide, lactoferricin. It was also demonstrated that oral administration of bLF augments host protection against infections via antimicrobial action and immunomodulation of the host. In addition, researchers have demonstrated that oral administration of bLF prevents cancer development. In this review, we look back on 25 years of bLF research and development.


Sujet(s)
Lactoferrine/pharmacologie , Administration par voie orale , Animaux , Anti-infectieux/administration et posologie , Anti-infectieux/métabolisme , Anti-infectieux/pharmacologie , Bovins , Humains , Intestins/effets des médicaments et des substances chimiques , Intestins/microbiologie , Lactoferrine/administration et posologie , Lactoferrine/métabolisme , Lactoferrine/physiologie
3.
Biomed Chromatogr ; 21(10): 1016-22, 2007 Oct.
Article de Anglais | MEDLINE | ID: mdl-17474141

RÉSUMÉ

Simultaneous determination of 3,4-methylenedioxymethamphetamine (MDMA) and 3,4-methylenedioxyamphetamine (MDA) in rat blood and brain microdialysates by high-performance liquid chromatography with fluorescence detection (HPLC-FL) was developed. Microdialysates were directly subjected to derivatization with 4-(4,5-diphenyl-1H-imidazol-2-yl)benzoyl chloride (DIB-Cl). The DIB-derivatives of MDMA, MDA and the internal standard, 1-methyl-3-phenylpropylamine (MPPA), were isocratically separated on an ODS column using a mixture of 50 mm phosphate buffer (pH 7.0)-acetonitrile-methanol-2-propanol (50:45:5:2, v/v/v/v %) as an eluent at a flow rate of 1.5 mL/min. The calibration curves of MDA and MDMA spiked to blood and brain microdialysates were linear over the ranges 2.5-500 and 5.0-1000 ng/mL, respectively. The detection limits of MDA and MDMA were 1.2 and 4.2 for blood and 1.3 and 4.8 ng/mL for brain, respectively. Additionally, the intra- and the inter-assay precisions were lower than 5.6% for the blood and brain microdialysates (n = 4). The proposed method was successfully applied for the monitoring of MDMA and its metabolite MDA in rat blood and brain microdialysates, and the pharmacokinetic parameters of MDMA and MDA in the microdialysates after administration of MDMA (5 mg/kg, i.p.) with or without caffeine (20 mg/kg, i.p.) were evaluated.


Sujet(s)
3,4-Méthylènedioxy-amphétamine/analyse , Chimie du cerveau , Colorants fluorescents/composition chimique , Microdialyse , N-Méthyl-3,4-méthylènedioxy-amphétamine/analyse , 3,4-Méthylènedioxy-amphétamine/composition chimique , 3,4-Méthylènedioxy-amphétamine/pharmacocinétique , Animaux , Benzoates/composition chimique , Analyse chimique du sang , Calibrage , Chromatographie en phase liquide à haute performance/instrumentation , Chromatographie en phase liquide à haute performance/méthodes , Imidazoles/composition chimique , Mâle , Microdialyse/instrumentation , Microdialyse/méthodes , N-Méthyl-3,4-méthylènedioxy-amphétamine/composition chimique , N-Méthyl-3,4-méthylènedioxy-amphétamine/pharmacocinétique , Plasma sanguin/composition chimique , Rats , Rat Wistar , Reproductibilité des résultats , Sensibilité et spécificité , Détection d'abus de substances/instrumentation , Détection d'abus de substances/méthodes
4.
Biomed Chromatogr ; 20(12): 1380-5, 2006 Dec.
Article de Anglais | MEDLINE | ID: mdl-17080504

RÉSUMÉ

A sensitive high-performance liquid chromatographic method with fluorescence detection to determine 3,4-methylenedioxymethamphethamine (MDMA) and 3,4-methylenedioxyamphethamine (MDA) in human and rat whole blood or plasma samples was developed by using 4-(4,5-diphenyl-1H-imidazol-2-yl)benzoyl chloride (DIB-Cl) as a label. MDMA and MDA in a small amount of blood sample (ca 100 microL) were extracted by liquid-liquid extraction with ethyl acetate, and were derivatized with DIB-Cl under mild conditions (10 min at room temperature). A good separation of DIB-derivatives could be achieved within 45 min using a commercially available ODS column with an isocratic eluent of 10 mM citric acid-20 mM Na(2)HPO(4) aqueous buffer (pH 4.0)-CH(3)CN-CH(3)OH (50:45:5, v/v/v %). The calibration curves prepared with 1-methyl-3-phenylpropylamine (MPPA) as an internal standard showed good linearity (r = 0.999) with 0.36-0.83 ng/mL detection limit at a signal-to-noise ratio of 3. MDMA and MDA in rat whole blood could be monitored for 6 h after a single administration of MDMA (2.2 mg/kg, i.p.). The pharmacokinetic parameters for MDMA and MDA obtained by triplicate measurements were 426 +/- 23 and 39 +/- 6 ng/mL (C(max)), 20 +/- 5 and 100 +/- 10 min (T(max)), respectively.


Sujet(s)
3,4-Méthylènedioxy-amphétamine/sang , Chromatographie en phase liquide à haute performance/méthodes , N-Méthyl-3,4-méthylènedioxy-amphétamine/sang , Animaux , Benzoates/composition chimique , Fluorescence , Colorants fluorescents/composition chimique , Humains , Imidazoles/composition chimique , Rats
5.
Biomed Chromatogr ; 20(6-7): 622-7, 2006.
Article de Anglais | MEDLINE | ID: mdl-16779783

RÉSUMÉ

A sensitive semi-micro column high-performance liquid chromatography with fluorescence detection method was developed for the determination of 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxyamphetamine (MDA), methamphetamine (MP) and amphetamine (AP) in human hair. 4-(4,5-Diphenyl-1H-imidazol-2-yl)benzoyl chloride (DIB-Cl) and 1-methyl-3-phenylpropylamine were used as labeling reagent and internal standard, respectively. These drugs were extracted from hair into 5% trifluoroacetic acid in methanol, and fluorescent labeled with DIB-Cl. The separation of DIB-derivatives was achieved on a reversed-phase semi-micro ODS column with an acetonitrile-methanol-water (30:40:30, v/v/v%) mixture as a mobile phase. The limits of detection at a signal-to-noise ratio of 3 for MDMA, MDA, MP and AP were 0.25, 0.15, 0.25 and 0.19 ng/mg, respectively. Precision of intra- and inter-day assay as the relative standard deviation were in the range 1.5-6.8% (n = 5) and 2.7-4.7% (n = 5), respectively. The proposed method was highly sensitive and able to detect MDMA and its related compounds in small amounts of hair sample, and could be applied to quantification of six abusers' hair samples.


Sujet(s)
3,4-Méthylènedioxy-amphétamine/analyse , Chromatographie en phase liquide à haute performance/méthodes , Poils/composition chimique , N-Méthyl-3,4-méthylènedioxy-amphétamine/analyse , Spectrométrie de fluorescence/méthodes , Humains , Normes de référence
6.
Luminescence ; 20(3): 210-5, 2005.
Article de Anglais | MEDLINE | ID: mdl-15924321

RÉSUMÉ

A simultaneous semi-micro column HPLC method with fluorescence detection of abused drugs, such as 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxyamphetamine (MDA), amphetamine (AP) and methamphetamine (MP) in rat urine was examined by using 4-(N,N-dimethylaminosulphonyl)-7-fluoro-1,2,3-benzoxadiazole (DBD-F) as a labelling reagent and alpha-phenylethylamine as an internal standard (IS). A sample (50 microL) of rat urine was added to 5 microL IS and 100 microL 100 mmol/L borate buffer (pH 12) and extracted with 1.5 mL n-hexane. After evaporation, 50 microL 75 mmol/L borate buffer (pH 8.5) and 50 microL 20 mmol/L DBD-F in CH3CN were added to the residue and mixed well. The resultant solution was heated for 20 min at 80 degrees C and then cooled in an ice bath. A good separation of DBD-derivatives could be achieved within 45 min using a semi-micro ODS column with an eluent of CH3CN/CH3OH/10 mmol/L imidazole-HNO3 buffer (pH 7.0) (= 45:5:50, v/v/v %). The DBD derivatives were monitored at 565 nm with an excitation at 470 nm. The calibration curves showed good linearity (r = 0.997) with 0.5-15 ng/mL detection limits at a S/N ratio of 3. MDMA and MDA in rat urine could be monitored for 15 h after a single administration of MDMA to rat (2.0 mg/kg, i.p.). The concentrations for MDMA and MDA (n = 3) were 0.13-160.1 and 0.17-10.9 microg/mL, respectively.


Sujet(s)
3,4-Méthylènedioxy-amphétamine/urine , N-Méthyl-3,4-méthylènedioxy-amphétamine/urine , Détection d'abus de substances/méthodes , Animaux , Borates , Calibrage , Chromatographie en phase liquide à haute performance , Composés diazonium , Surveillance des médicaments/méthodes , Fluorimétrie , Mâle , N-Méthyl-3,4-méthylènedioxy-amphétamine/administration et posologie , Rats , Rat Wistar , Détection d'abus de substances/normes
7.
J Food Prot ; 55(4): 238-240, 1992 Apr.
Article de Anglais | MEDLINE | ID: mdl-31071777

RÉSUMÉ

The susceptibility of Listeria monocytogenes to inhibition and inactivation by lactoferricin, a newly isolated antimicrobial peptide derived from bovine lactoferrin present in cow's milk, was studied in laboratory media. Lactoferricin showed an effectiveness similar to that of many clinically useful antibiotics, causing complete inhibition of four strains of L. monocytogenes (serotypes 1b, 2, 3, and 4a) at low concentrations varying within the range of 0.3 to 9 µg/ml depending on the strain and the culture medium used. The effectiveness of lactoferricin against L. monocytogenes was not strongly affected by the presence of various carbohydrates or proteins but was somewhat diminished in the presence of various salts. The peptide showed potent activity over the pH range of 5.5 to 7.5. The effect of lactoferricin was lethal, causing a rapid loss of colony-forming ability with all four strains tested.

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