Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Filtrar
Más filtros












Base de datos
Intervalo de año de publicación
1.
J Antibiot (Tokyo) ; 76(6): 324-334, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36997727

RESUMEN

Allantopyrone A is an α-pyrone metabolite that was originally isolated from the endophytic fungus Allantophomopsis lycopodina KS-97. We previously demonstrated that allantopyrone A exhibits anti-cancer, anti-inflammatory, and neuroprotective activities. In the present study, we showed that allantopyrone A up-regulated the protein expression of hypoxia-inducible factor (HIF)-1α in human fibrosarcoma HT-1080 cells. It also up-regulated the mRNA expression of BNIP3 and ENO1, but not other HIF target genes or HIF1A. Allantopyrone A did not inhibit the prolyl hydroxylation of HIF-1α, but enhanced the ubiquitination of cellular proteins. Consistent with this result, chymotrypsin-like and trypsin-like proteasome activities were reduced, but not completely inactivated by allantopyrone A. Allantopyrone A decreased the amount of proteasome catalytic subunits. Therefore, the present results showed that allantopyrone A interfered with the degradation of HIF-1α protein by reducing proteasome activity in human fibrosarcoma HT-1080 cells.


Asunto(s)
Fibrosarcoma , Complejo de la Endopetidasa Proteasomal , Humanos , Pironas/farmacología , Fibrosarcoma/tratamiento farmacológico , Hipoxia , Subunidad alfa del Factor 1 Inducible por Hipoxia
2.
Int J Mol Sci ; 23(13)2022 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-35806134

RESUMEN

Pro-inflammatory cytokines, such as tumor necrosis factor-α (TNF-α), induce the expression of intracellular adhesion molecule-1 (ICAM-1) by activating the nuclear factor κB (NF-κB) signaling pathway. In the present study, we found that cucurbitacin B decreased the expression of ICAM-1 in human lung adenocarcinoma A549 cells stimulated with TNF-α or interleukin-1α. We further investigated the mechanisms by which cucurbitacin B down-regulates TNF-α-induced ICAM-1 expression. Cucurbitacin B inhibited the nuclear translocation of the NF-κB subunit RelA and the phosphorylation of IκBα in A549 cells stimulated with TNF-α. Cucurbitacin B selectively down-regulated the expression of TNF receptor 1 (TNF-R1) without affecting three adaptor proteins (i.e., TRADD, RIPK1, and TRAF2). The TNF-α-converting enzyme inhibitor suppressed the down-regulation of TNF-R1 expression by cucurbitacin B. Glutathione, N-acetyl-L-cysteine, and, to a lesser extent, L-cysteine attenuated the inhibitory effects of cucurbitacin B on the TNF-α-induced expression of ICAM-1, suggesting that an α,ß-unsaturated carbonyl moiety is essential for anti-inflammatory activity. The present results revealed that cucurbitacin B down-regulated the expression of TNF-R1 at the initial step in the TNF-α-dependent NF-κB signaling pathway.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Células A549 , Adenocarcinoma del Pulmón/tratamiento farmacológico , Humanos , Molécula 1 de Adhesión Intercelular/genética , Molécula 1 de Adhesión Intercelular/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , FN-kappa B/metabolismo , Receptores Tipo I de Factores de Necrosis Tumoral/genética , Transducción de Señal , Triterpenos , Factor de Necrosis Tumoral alfa/metabolismo
3.
Nucleosides Nucleotides Nucleic Acids ; 29(4-6): 504-8, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20544544

RESUMEN

OBJECTIVE: It has been demonstrated that uridine infusion induces insulin resistance in rats. Furthermore, it was recently reported that plasma uridine is correlated with homeostasis model assessment of insulin resistance (HOMA-R) in hypertensive patients. Therefore, we investigated whether plasma uridine was correlated with HOMA-R in patients with non-insulin-dependent diabetes mellitus (NIDDM). SUBJECTS AND METHODS: The subjects were 23 male patients with NIDDM (average age 63 years) and 18 healthy males (average age 60 years). Blood samples were drawn after an overnight fast, plasma uridine was then measured using high-performance liquid chromatography. RESULTS: The average plasma uridine concentration in patients with NIDDM was higher than that in healthy subjects (P < 0.05). Furthermore, plasma uridine values were positively correlated with HOMA-R (r = 0.48, P < 0.05), serum insulin (r = 0.46, P < 0.05), and serum C-peptide radioimmunoreactivity (CPR) (r = 0.44, P < 0.05) values, whereas they were not significantly correlated with fasting blood glucose or hemoglobin A1c values. CONCLUSION: We found a positive relationship between plasma uridine value and HOMA-R, serum insulin, and CPR, suggesting that plasma uridine is a marker of insulin resistance in patients with NIDDM.


Asunto(s)
Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/fisiopatología , Resistencia a la Insulina/fisiología , Uridina/sangre , Adulto , Anciano , Análisis de Varianza , Cromatografía Líquida de Alta Presión , Humanos , Masculino , Persona de Mediana Edad
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...