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1.
Biochem Biophys Res Commun ; 535: 1-5, 2021 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-33340760

RESUMEN

Reactive oxygen species (ROS) are highly reactive and directly attack surrounding biomolecules to deteriorate cellular and tissue functions. Meanwhile, ROS also serve as signaling mediators to upregulate pro-inflammatory cytokine expression via activation of the nuclear factor kappa B signaling pathway, and the increased pro-inflammatory cytokines trigger respiratory burst of inflammatory cells that further accelerates ROS production in the inflamed tissue. Such crosstalk between ROS and inflammatory responses leads to a chain reaction of negativity, and cause progression of several chronic pathologies. Since molecular hydrogen is known to preferentially remove cytotoxic hydroxyl radicals and peroxynitrites, and to prevent cell and tissue damage, we here examined whether electrolyzed hydrogen water (EHW) enriched with molecular hydrogen and reactive hydrogen storing platinum nanoparticles dissolved from an electrode could alleviate oxidative stress and inflammation induced by continuous stress challenges. Five-day continuous stress loading to rats elevated reactive oxygen metabolites-derived compounds (d-ROMs), interleukin (IL)-1ß, and adrenocorticotropic hormone (ACTH) levels and decreased the biological antioxidant potential (BAP) level. Drinking EHW during 5-day continuous stress loading significantly alleviated all of these changes. The results suggest that EHW could suppress stress-response-associated oxidative stress and IL-1ß level elevation in vivo, and that drinking of EHW is effective for controlling stress responses via its antioxidant potential.


Asunto(s)
Antiinflamatorios/farmacología , Antioxidantes/farmacología , Electrólisis , Hidrógeno/farmacología , Estrés Oxidativo/efectos de los fármacos , Agua/farmacología , Hormona Adrenocorticotrópica/sangre , Animales , Electrodos , Hidrógeno/administración & dosificación , Inflamación/sangre , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Interleucina-18/sangre , Masculino , Ratas , Especies Reactivas de Oxígeno/metabolismo , Agua/administración & dosificación
2.
Angew Chem Int Ed Engl ; 59(32): 13385-13390, 2020 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-32356371

RESUMEN

The dinuclear copper enzyme, tyrosinase, activates O2 to form a (µ-η2 :η2 -peroxido)dicopper(II) species, which hydroxylates phenols to catechols. However, the exact mechanism of phenolase reaction in the catalytic site of tyrosinase is still under debate. We herein report the near atomic resolution X-ray crystal structures of the active tyrosinases with substrate l-tyrosine. At their catalytic sites, CuA moved toward l-tyrosine (CuA1 → CuA2), whose phenol oxygen directly coordinates to CuA2, involving the movement of CuB (CuB1 → CuB2). The crystal structures and spectroscopic analyses of the dioxygen-bound tyrosinases demonstrated that the peroxide ligand rotated, spontaneously weakening its O-O bond. Thus, the copper migration induced by the substrate-binding is accompanied by rearrangement of the bound peroxide species so as to provide one of the peroxide oxygen atoms with access to the phenol substrate's ϵ carbon atom.


Asunto(s)
Cobre/metabolismo , Monofenol Monooxigenasa/metabolismo , Oxígeno/metabolismo , Tirosina/metabolismo , Aspergillus oryzae/enzimología , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Biocatálisis , Dominio Catalítico , Cobre/química , Cristalografía por Rayos X , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Modelos Químicos , Monofenol Monooxigenasa/química , Oxígeno/química , Unión Proteica , Streptomyces/enzimología , Tirosina/química
3.
Biotechnol J ; 18(12): e2300328, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37559489

RESUMEN

Primordial germ cells (PGCs) that can differentiate into gametes are used to produce genome-edited chickens. However, the transfection efficiency into PGCs is low in chickens; therefore, the yield efficiency of PGCs modified via genome editing is problematic. In this study, we improved transfection efficiency and achieved highly efficient genome editing in chicken PGCs. For transfection, we used lipofection, which is convenient for gene transfer. Chicken PGC cultures require adding heparin to support growth; however, heparin significantly reduces lipofection efficiency (p < 0.01). Heparin-induced lipofection efficiency was restored by adding protamine. Based on these results, we optimized gene transfer into chicken PGCs. Lipofectamine 2000 and our PGC medium were the most efficient transfection reagent and medium, respectively. Finally, based on established conditions, we compared the gene knock-out efficiencies of ovomucoid, a major egg allergen, and gene knock-in efficiencies at the ACTB locus. These results indicate that optimized lipofection is useful for CRISPR/Cas9-mediated knock-out and knock-in. Our findings may contribute to the generation of genome-edited chickens and stimulate research in various applications involving them.


Asunto(s)
Sistemas CRISPR-Cas , Pollos , Animales , Pollos/genética , Sistemas CRISPR-Cas/genética , Heparina , Transfección , Edición Génica/métodos , Células Germinativas
4.
Front Immunol ; 14: 1261256, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38022622

RESUMEN

Introduction: A series of symptoms, including fever, widespread pain, fatigue, and even ageusia, have frequently been reported in the context of various infections, such as COVID-19. Although the pathogenic mechanisms underlying an infection causing fever and pain have been well established, the mechanisms of fatigue induced by infection in specific brain regions remain unclear. Methods: To elucidate whether and how the peripheral infection cause fatigue via regional neuroinflammation, we performed a brain-wide investigation of neuroinflammation in a peripheral pseudoinfection rat model using [18F]DPA-714 positron emission tomography (PET) imaging analysis, in which the polyriboinosinic: polyribocytidylic acid (poly I:C) was intraperitoneally injected. Results: Transient fever lasting for several hours and subsequent suppression of spontaneous activity lasting a few days were induced by poly I:C treatment. Significant increase in plasma interleukin (IL)-1ß, IL-6 and tumour necrosis factor (TNF)-α were observed at 2 and 4 h following poly I:C treatment. PET imaging analysis revealed that the brain uptake of [18F]DPA-714 was significantly increased in several brain regions one day after poly I:C treatment, such as the dorsal raphe (DR), parvicellular part of red nucleus (RPC), A5 and A7 noradrenergic nucleus, compared with the control group. The accumulation of [18F]DPA-714 in the DR, RPC and A5 was positively correlated with subsequent fatigue-like behavior, and that in the A7 tended to positively correlate with fever. Discussion: These findings suggest that peripheral infection may trigger regional neuroinflammation, which may cause specific symptoms such as fatigue. A similar mechanism might be involved in COVID-19.


Asunto(s)
COVID-19 , Enfermedades Neuroinflamatorias , Ratas , Animales , Tomografía de Emisión de Positrones/métodos , Dolor , COVID-19/complicaciones , Poli I
5.
Nutrients ; 14(21)2022 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-36364715

RESUMEN

Inflammatory bowel disease (IBD) is characterized by chronic inflammation of the digestive tract and is typically accompanied by characteristic symptoms, such as abdominal pain, diarrhea, and bloody stool, severely deteriorating the quality of the patient's life. Electrolyzed hydrogen water (EHW) has been shown to alleviate inflammation in several diseases, such as renal disease and polymyositis/dermatomyositis. To investigate whether and how daily EHW consumption alleviates abdominal pain, the most common symptom of IBD, we examined the antioxidative and anti-inflammatory effects of EHW in an IBD rat model, wherein colonic inflammation was induced by colorectal administration of 2,4,6-trinitrobenzene sulfonic acid (TNBS). We found that EHW significantly alleviated TNBS-induced abdominal pain and tissue inflammation. Moreover, the production of proinflammatory cytokines in inflamed colon tissue was also decreased significantly. Meanwhile, the overproduction of reactive oxygen species (ROS), which is intricately involved in intestinal inflammation, was significantly suppressed by EHW. Additionally, expression of S100A9, an inflammatory biomarker of IBD, was significantly suppressed by EHW. These results suggest that the EHW prevented the overproduction of ROS due to its powerful free-radical scavenging ability and blocked the crosstalk between oxidative stress and inflammation, thereby suppressing colonic inflammation and alleviating abdominal pain.


Asunto(s)
Colitis , Enfermedades Inflamatorias del Intestino , Ratas , Animales , Especies Reactivas de Oxígeno/metabolismo , Hidrógeno/farmacología , Hidrógeno/metabolismo , Agua/metabolismo , Enfermedades Inflamatorias del Intestino/metabolismo , Colon/metabolismo , Ácido Trinitrobencenosulfónico/toxicidad , Inflamación/metabolismo , Dolor Abdominal/etiología , Colitis/inducido químicamente , Colitis/metabolismo
6.
RSC Med Chem ; 13(10): 1197-1204, 2022 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-36325399

RESUMEN

Transient receptor potential cation channel subfamily V member 1 (TRPV1)-targeted compounds were synthesized by modifying the structure of SB366791, a pharmaceutically representative TRPV1 antagonist. To avoid amide-iminol tautomerization, structurally supported N-methylated amides (i.e., 3-alkoxy-substitued N-meythylamide derivatives of SB366791) were evaluated using a Ca2+ influx assay, in which cells expressed recombinant TRPV1 in the presence of 1.0 µM capsaicin. The antagonistic activities of N-(3-methoxyphenyl)-N-methyl-4-chlorocinnamamide (2) (RLC-TV1004) and N-{3-(3-fluoropropoxy)phenyl}-N-methyl-4-chlorocinnamamide (4) (RLC-TV1006) were found to be approximately three-fold higher (IC50: 1.3 µM and 1.1 µM, respectively) than that of SB366791 (IC50: 3.7 µM). These results will help reinvigorate the potential of SB366791 in medicinal chemistry applications. The 3-methoxy and 3-fluoroalkoxy substituents were used to obtain radioactive [11C]methoxy- or [18F]fluoroalkoxy-incorporated tracers for in vivo positron emission tomography (PET). Using the 11C- or 18F-labeled derivatives, explorative PET imaging trials were performed in rats.

7.
Neurosci Res ; 165: 45-50, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32361157

RESUMEN

Chronic fatigue syndrome (CFS) is characterized by long-lasting fatigue, and a range of symptoms, and is involved in homeostasis disruption. CFS patients frequently complain of low grade fever or chill even under normal body temperature indicating that thermosensory or thermoregulatory functions might be disturbed in CFS. However, little is known about the detailed mechanisms. To elucidate whether and how thermoregulatory function was altered during the development of chronic fatigue, we investigated temporal changes in body temperature with advance of fatigue accumulation in a chronic fatigue rat model using a wireless transponder. Our findings demonstrated that the body temperature was adaptively increased in response to fatigue loading in the early phase, but unable to retain in the late phase. The tail heat dissipation was often observed and the frequency of tail heat dissipation gradually increased initially, then decreased. In the late phase of fatigue loading, the body temperature for the tail heat dissipation phase decreased to a value lower than that for the non-dissipation phase. These results suggest that adaptive changes in thermoregulatory function occurred with fatigue progression, but this system might be disrupted by long-lasting fatigue, which may underlie the mechanism of fatigue chronification.


Asunto(s)
Síndrome de Fatiga Crónica , Animales , Temperatura Corporal , Regulación de la Temperatura Corporal , Humanos , Ratas , Temperatura
8.
Elife ; 62017 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-28799896

RESUMEN

Mechanisms underlying the central regulation of food intake and fat accumulation are not fully understood. We found that neurosecretory protein GL (NPGL), a newly-identified neuropeptide, increased food intake and white adipose tissue (WAT) in rats. NPGL-precursor gene overexpression in the hypothalamus caused increases in food intake, WAT, body mass, and circulating insulin when fed a high calorie diet. Intracerebroventricular administration of NPGL induced de novo lipogenesis in WAT, increased insulin, and it selectively induced carbohydrate intake. Neutralizing antibody administration decreased the size of lipid droplets in WAT. Npgl mRNA expression was upregulated by fasting and low insulin levels. Additionally, NPGL-producing cells were responsive to insulin. These results point to NPGL as a novel neuronal regulator that drives food intake and fat deposition through de novo lipogenesis and acts to maintain steady-state fat level in concert with insulin. Dysregulation of NPGL may be a root cause of obesity.


Asunto(s)
Ingestión de Alimentos , Hipotálamo/metabolismo , Lipogénesis , Proteínas del Tejido Nervioso/metabolismo , Obesidad/fisiopatología , Animales , Perfilación de la Expresión Génica , Insulina/metabolismo , Proteínas del Tejido Nervioso/genética , Ratas
9.
Endocrinology ; 158(5): 1120-1129, 2017 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-28323972

RESUMEN

We have recently identified from the avian hypothalamus a complementary DNA encoding a small secretory protein termed neurosecretory protein GL (NPGL). In chicks, NPGL increases body weight gain without affecting food intake. A database search reveals that NPGL is conserved throughout vertebrates. However, the central distribution and functional role of NPGL remains to be elucidated in mammals. In this study, we identified the precursor complementary DNA encoding NPGL from the mouse hypothalamus. Quantitative reverse transcription polymerase chain reaction and morphological analyses revealed that NPGL precursor messenger RNA is robustly expressed in the mediobasal hypothalamus with NPGL neurons specifically localized to the lateroposterior part of the arcuate nucleus in the hypothalamus. NPGL-immunoreactive fibers were observed in close anatomical contact with pro-opiomelanocortin neurons in the rostral region of the arcuate nucleus. NPGL messenger RNA expression was elevated by 24-hour fasting and reduced by feeding of a high-fat diet for 5 weeks. Furthermore, intracerebroventricular injection of mature NPGL increased food intake, pointing to an important role in feeding. Taken together, these findings report on the distribution of NPGL in the mammalian brain and point to an important role for this neuropeptide in energy homeostasis.


Asunto(s)
Metabolismo Energético/genética , Hipotálamo/metabolismo , Proteínas del Tejido Nervioso/fisiología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Dieta Alta en Grasa , Ayuno/metabolismo , Regulación de la Expresión Génica , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas del Tejido Nervioso/genética , Neuropéptidos/metabolismo , Distribución Tisular
10.
Oncol Lett ; 11(1): 208-212, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26870190

RESUMEN

The CyberKnife® is expected to be a novel local treatment for hepatocellular carcinoma (HCC), however, a long-term follow-up using dynamic computed tomography and magnetic resonance imaging is required to determine the effect of treatment in a number of the affected patients. Therefore, there is a requirement to evaluate procedures for early determination of the effect of CyberKnife treatment. The present study aimed to evaluate the changes in the hemodynamics of the tumors and the hepatic parenchyma surrounding the tumor prior to and following CyberKnife treatment for HCC. A total of 4 HCC patients were enrolled in this study. These patients underwent CyberKnife treatment and were evaluated by image analysis prior to and following treatment using contrast-enhanced ultrasonography (CEUS) with Sonazoid. CEUS was performed prior to treatment, at 2 and 4 weeks post-treatment, and every 4 weeks thereafter for as long as possible. The dynamics of the enhancement of the tumor and the hepatic parenchyma surrounding the tumor in the vascular phase, and the presence or absence of a hypoechoic area in the hepatic parenchyma surrounding the tumor in the post-vascular phase were assessed. Results showed that: i) In the patient with earlier changes, hemodynamic changes were evident in the tumor at 4 weeks and in the hepatic parenchyma surrounding the tumor at 2 weeks post-treatment, respectively; ii) the tumor showed hypoenhancement in all patients; and iii) with regard to findings in the hepatic parenchyma surrounding the tumor, strong hyperenhancement appeared in the vascular phase initially, followed by a hypoechoic area in the post-vascular phase. Evaluation of the hemodynamics of tumors and hepatic parenchyma surrounding the tumor using CEUS with Sonazoid may be therapeutically applicable, as it is less invasive than dynamic computed tomography (CT) and provides an early evaluation of the effectiveness of CyberKnife treatment.

12.
Chem Asian J ; 3(8-9): 1336-42, 2008 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-18506868

RESUMEN

(1)H NMR chemical shifts of molecular hydrogen encapsulated in dichloromethyl-C(60) cation and (1-octynyl)-C(60) anion were studied to clarify the difference in magnetic shielding effects inside the fullerene cages. The signals of the H(2) molecule inside both cationic and anionic C(60) cages appeared at lower fields than those of the neutral counterparts. These results were interpreted based on the results of NICS calculations. It was demonstrated that the H(2) molecule inside the C(60) cages can serve as an excellent NMR probe of aromaticity for both cationic and anionic C(60) derivatives.

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