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1.
Sci Rep ; 8(1): 6335, 2018 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-29679037

RESUMEN

Psoriasis is a common inflammatory disease. It affects 1-3% of the population worldwide and is associated with increasing medical costs every year. Typical psoriatic skin lesions are reddish, thick, scaly plaques that can occur on multiple skin sites all over the body. Topical application of imiquimod (IMQ), a toll-like receptor (TLR)7 agonist and potent immune system activator, can induce and exacerbate psoriasis. Previous studies have demonstrated that isoflavone extract has an antioxidant effect which may help decrease inflammation and inflammatory pain. Through in vivo studies in mice, we found that the topical application to the shaved back and right ear of mice of isoflavone extract prior to IMQ treatment significantly decreased trans-epidermal water loss (TEWL), erythema, blood flow speed, and ear thickness, while it increased surface skin hydration, and attenuated epidermal hyperplasia and inflammatory cell infiltration. Through in vitro experiments, we found that isoflavone extract can reduce IL-22, IL-17A, and TNF-α-induced MAPK, NF-κB, and JAK-STAT activation in normal human epidermal keratinocytes. At the mRNA level, we determined that isoflavone extract attenuated the increased response of the TNF-α-, IL-17A-, and IL-22- related pathways. These results indicate that isoflavone extract has great potential as an anti-psoriatic agent and in the treatment of other inflammatory skin diseases.


Asunto(s)
Isoflavonas/farmacología , Queratinocitos/efectos de los fármacos , Psoriasis/tratamiento farmacológico , Animales , Antioxidantes/farmacología , Citocinas/metabolismo , Modelos Animales de Enfermedad , Epidermis/efectos de los fármacos , Epidermis/metabolismo , Prepucio , Humanos , Imiquimod , Inflamación/patología , Interleucina-17/metabolismo , Interleucinas/metabolismo , Isoflavonas/uso terapéutico , Masculino , Ratones , Ratones Endogámicos BALB C , FN-kappa B/metabolismo , Transducción de Señal/efectos de los fármacos , Piel/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Interleucina-22
2.
Am J Chin Med ; 45(6): 1273-1291, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28893091

RESUMEN

Lutein is a carotenoid with anti-oxidant properties. Autophagy, an evolutionarily conserved catabolic cellular pathway for coping with stress conditions, is responsive to reactive oxygen species (ROS) and degrades damaged organelles. We previously demonstrated that lutein can induce anti-oxidant enzymes to relieve methotrexate-induced ROS stress. We therefore hypothesized that lutein, which activates ROS-scavenging enzymes, can also induce autophagy for cell survival. In this study, we demonstrated that lutein treatment attenuated the reduction in cell viability caused by H2O2. Lutein dose-dependently induced the processing of microtubule-associated protein light chain 3 (LC3)-II, an autophagy marker protein, and accumulation of LC3-positive puncta in rat intestinal IEC-6 cells. Furthermore, (a) direct observation of autophagosome formation through transmission electron microscopy, (b) upregulation of autophagy-related genes including ATG4A, ATG5, ATG7, ATG12, and beclin-1 (BENC1), and (c) increased BECN1/Bcl-2 ratio confirmed the induction of autophagy by lutein. The results revealed that bafilomycin-A1-induced inhibition of autophagy reduced cell viability and increased apoptosis in lutein-treated cells, indicating a protective role of lutein-induced autophagy. Lutein treatment also activated adenosine monophosphate-activated protein kinase (AMPK), c-Jun N-terminal kinase (JNK), and p-38, but had no effects on the induction of extracellular signal-related kinase or inhibition of mTOR; however, the inhibition of activated AMPK, JNK, or p-38 did not attenuate lutein-induced autophagy. Finally, increased BECN1 expression levels were detected in lutein-treated cells, and BECN1 knockdown abolished autophagy induction. These results suggest that lutein-induced autophagy was mediated by the upregulation of BECN1 in IEC-6 cells. We are the first to demonstrate that lutein induces autophagy. Elevated autophagy in lutein-treated IEC-6 cells may have a protective role against various stresses, and this warrants further investigation.


Asunto(s)
Antioxidantes , Proteínas Relacionadas con la Autofagia/genética , Proteínas Relacionadas con la Autofagia/metabolismo , Autofagia/efectos de los fármacos , Autofagia/genética , Beclina-1/genética , Beclina-1/metabolismo , Células Epiteliales/citología , Células Epiteliales/fisiología , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Regulación del Desarrollo de la Expresión Génica/genética , Intestinos/citología , Luteína/farmacología , Regulación hacia Arriba/efectos de los fármacos , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Células Cultivadas , Relación Dosis-Respuesta a Droga , Depuradores de Radicales Libres/metabolismo , MAP Quinasa Quinasa 4/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/genética , Ratas , Especies Reactivas de Oxígeno
3.
Dalton Trans ; 44(38): 16675-9, 2015 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-26347333

RESUMEN

A new type of TeFe3(CO)9-incorporated dicopper NHC complex was obtained directly from one-pot reactions. By the introduction of the cluster anion [TeFe3(CO)9](2-) and NHCs as the ligands, these di-Cu(i)-based complexes exhibited pronounced catalytic activities toward the homocoupling of arylboronic acids with low Cu loadings and high yields (up to 98%).

4.
Biomed Res Int ; 2015: 906039, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25815340

RESUMEN

The differential effects of a selective kappa- (κ-) opioid receptor agonist, U50488, were elucidated by monitoring the contraction of isolated guinea pig atrial and ventricular muscles. In electrically driven left atria, U50488 in nanomolar concentration range decreased the contractile force. Norbinaltorphimine (norBNI), a selective κ-receptor antagonist, and pertussis toxin (PTX) abolished the negative inotropic effect of U50488. In contrast, the inhibitory effect was not affected by the pretreatment of atropine or propranolol. Even though U50488 exerted a negative inotropic effect in the left atrium, it did not affect the contractile force of the right atrium and ventricles paced at 2 Hz. Similarly, the beating rate of the spontaneously beating right atrium was also unaffected by U50488. These results indicate that the activation of κ-opioid receptors can only produce negative inotropic effect in left atria via activation of PTX-sensitive G protein in guinea pigs. The absence of negative inotropic effects in right atria and ventricles suggests that there may be a greater distribution of functional κ-opioid receptors in guinea pig left atria than in right atria and ventricles, and the distribution of the receptors may be species-specific.


Asunto(s)
3,4-Dicloro-N-metil-N-(2-(1-pirrolidinil)-ciclohexil)-bencenacetamida, (trans)-Isómero/administración & dosificación , Atrios Cardíacos/efectos de los fármacos , Ventrículos Cardíacos/efectos de los fármacos , Receptores Opioides kappa/metabolismo , Animales , Atropina/administración & dosificación , Proteínas de Unión al GTP/biosíntesis , Cobayas , Atrios Cardíacos/metabolismo , Atrios Cardíacos/patología , Ventrículos Cardíacos/metabolismo , Ventrículos Cardíacos/patología , Técnicas de Cultivo de Órganos , Propranolol/administración & dosificación , Receptores Opioides kappa/agonistas
5.
Org Lett ; 16(20): 5275-7, 2014 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-25265044

RESUMEN

A highly strained 1,3-fused tricyclic cyclopropene, tricyclo[3.2.2.0(2,4)]nona-2,6-diene (15), was designed for use in the synthesis of a new highly strained anti-Bredt compound, bicyclo[3.2.2]nona-1,6,8-triene (17). Tricyclic cyclopropene 15 was subjected to a ring-opening reaction followed by insertion of the resulting carbene to produce an anti-Bredt compound 17. The tricyclic cyclopropene 15 was prepared by the fluoride-induced elimination of 2-chloro-3-trimethylsilyltricyclo[3.2.2.0(2,4)]non-6-ene (20), via the reaction of 1-chloro-3-trimethylsilylcyclopropene with 1,3-cyclohexadiene. Both the tricyclic cyclopropene 15 and the anti-Bredt compound 17 were trapped by diphenylisobenzofuran (DPIBF).

6.
PLoS One ; 8(9): e72553, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24039779

RESUMEN

PURPOSE: High-dose chemotherapy using methotrexate (MTX) frequently induces side effects such as mucositis that leads to intestinal damage and diarrhea. Several natural compounds have been demonstrated of their effectiveness in protecting intestinal epithelial cells from these adverse effects. In this paper, we investigated the protection mechanism of lutein against MTX-induced damage in IEC-6 cells originating from the rat jejunum crypt. METHODS: The cell viability, induced-apoptosis, reactive oxygen species (ROS) generation, and mitochondrial membrane potential in IEC-6 cells under MTX treatment were examined in the presence or absence of lutein. Expression level of Bcl2, Bad and ROS scavenging enzymes (including SOD, catalase and Prdx1) were detected by quantitative RT-PCR. RESULTS: The cell viability of IEC-6 cells exposed to MTX was decreased in a dose- and time-dependent manner. MTX induces mitochondrial membrane potential loss, ROS generation and caspase 3 activation in IEC-6 cells. The cytotoxicity of MTX was reduced in IEC-6 cells by the 24 h pre-treatment of lutein. We found that pre-treatment of lutein significantly reduces MTX-induced ROS and apoptosis. The expression of SOD was up-regulated by the pre-treatment of lutein in the MTX-treated IEC-6 cells. These results indicated that lutein can protect IEC-6 cells from the chemo-drugs induced damage through increasing ROS scavenging ability. CONCLUSION: The MTX-induced apoptosis of IEC-6 cells was shown to be repressed by the pre-treatment of lutein, which may represent a promising adjunct to conventional chemotherapy for preventing intestinal damages.


Asunto(s)
Antimetabolitos Antineoplásicos/toxicidad , Apoptosis/efectos de los fármacos , Luteína/farmacología , Metotrexato/toxicidad , Especies Reactivas de Oxígeno/metabolismo , Animales , Caspasa 3/metabolismo , Catalasa/metabolismo , Línea Celular , Supervivencia Celular/efectos de los fármacos , Citoprotección , Activación Enzimática , Células Epiteliales/efectos de los fármacos , Células Epiteliales/fisiología , Mucosa Intestinal/citología , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Estrés Oxidativo , Peroxirredoxinas/metabolismo , Ratas , Superóxido Dismutasa/metabolismo
7.
Chem Commun (Camb) ; 46(27): 5009-11, 2010 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-20523935

RESUMEN

The addition of heteroaryllithium to various ketones followed by dehydration gave 1-(2-heteroaryl)cycloalkenes and (2-hetero- aryl)alkenes. When alkenes were treated with 10 mol% NIS, calix[4]thiophenes and calix[4]furans were obtained in good yields.

8.
J Org Chem ; 74(20): 7994-7, 2009 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-19761203

RESUMEN

1-Bromo-2-phenylcyclopropene (2) underwent [2+2] dimerization to generate 1,2-dibromo-4,5-diphenyltricyclo[3.1.0.0(2,4)]hexane (5), which was heated to form 1,2-dibromo-4,5-diphenylcyclohexa-1,4-diene (6) followed by oxidation to yield 4',5'-dibromo-o-terphenyl (7). o-Terphenyl 7 could be synthesized in one-pot reactions from 1,1,2-tribromocyclopropane (3). When cyclopropane 3 was treated with 1.5 equiv of methyllithium followed by slowly adding the proton source, crossed [2+2] adduct 8 was isolated in 40% yield. Compound 8 was heated and oxidated to produce 4'-bromo-o-terphenyl (11).

9.
Org Lett ; 10(9): 1843-5, 2008 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-18399650

RESUMEN

Treatment of 1-bromo-2,2-dichloro-3-trimethylsilylcyclopropane with CsF in THF refluxing temperature gave chlorocyclopropenyl cation (1), which reacted with various nucleophiles to generate 3-monosubstituted 1-chlorocyclopropenes. The Diels-Alder reactions of 3-monosubstituted 1-chlorocyclopropenes with 1,3-diphenylisobenzofuran (DPIBF) yielded only the exo-anti adducts in excellent yield. When cation 1 was treated with water and trapped with DPIBF, an aldehyde, 12, was isolated.

10.
J Org Chem ; 69(25): 8949-51, 2004 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-15575781

RESUMEN

1-Phenylcyclopropene (1) was synthesized by treatment of 1,1,2-tribromo-2-phenylcyclopropane (2) with 2.5 equiv of methyllithium followed by protonation. Compound 1 underwent ene dimerization to form ene dimer 5 followed by ene reaction with monomer 1 (enophile) to give an ene trimer 6. Both of these two ene reactions derived endo transition states. In the meantime, the [2+2] adduct, trans-1,2-diphenylbicyclo[3.1.0.0(2,4)]hexane (7), was also formed. When the adduct 7 was heated at THF refluxing temperature, 1,2-diphenylcyclohexa-1,4-diene (8) was obtained. Compound 8 was treated with DDQ to yield o-diphenylbenzene.


Asunto(s)
Ciclopropanos/química , Ciclopropanos/síntesis química , Modelos Moleculares , Conformación Molecular , Pirrolidinonas/química , Estereoisomerismo
11.
J Org Chem ; 62(10): 3355-3359, 1997 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-11671723

RESUMEN

Two 1,2-bridged tricyclic cyclopropenes, tricyclo[3.2.1.0(2,4)]oct-2(4)-ene (6) and tricyclo[3.2.1.0(2,4)]octa-2(4),6-diene (7), have been synthesized by elimination of 2-bromo-4-chlorotricyclo[3.2.1.0(2,4)]octane (17) and 2-bromo-4-chlorotricyclo[3.2.1.0(2,4)]oct-6-ene (8), respectively. Both 6 and 7 were trapped with diphenylisobenzofuran to form two isomers: exo-addition of cyclopropenes and exo-addition of bicyclo[2.2.1]heptenes (exo-exo adducts) and endo-addition of cyclopropenes and exo-addition of bicyclo[2.2.1]heptenes (endo-exo adducts). The stereoselectivity of the Diels-Alder reactions of 6 and 7 with DPIBF is different. The exo-exo/endo-exo ratios of 6 and 7 with DPIBF are 2/1 and 1/2, respectively. Both exo-exo adducts 12 and 18 are stable at refluxing chloroform temperature either with or without DPIBF, but endo-exo adducts 15 and 22 are unstable at room temperature and either isomerize to styrenes 13 and 19 or react with oxygen in the absence of catalyst to generate epoxides 14 and 20. Both styrenes 13 and 19 can be photooxidized by oxygen to give epoxides 14 and 20.

12.
J Org Chem ; 61(2): 764-770, 1996 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-11667002

RESUMEN

Bicyclo[4.1.0]hept-1,6-ene has been generated by elimination of 1-chloro-2-(trimethysilyl)bicyclo[4.1.0]heptane in the gas phase over solid fluoride at 25 degrees C. The cyclopropene dimerizes by a rapid ene reaction forming two diastereomeric cyclopropenes. In tetrahydrofuran or chloroform the ene dimers couple to form a single crystalline triene tetramer, whereas a mixture of tricyclohexane tetramers is formed when the neat dimers are allowed to warm to room temperature. Oxidation by dimethyldioxirane or dioxygen gives carbonyl products. Quantum mechanical calculations yielded an increase in strain of approximately 17 kcal/mol over that for 1,2-dimethylcyclopropene. The potential enegy barrier to flexing (folding) along the fused double bond of bicyclo[4.1.0]hept-1,6-ene is only approximately 1 kcal/mol at the highest level of theory investigated.

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