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1.
Chemistry ; : e202402712, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39136591

RESUMEN

Difunctionalizations of alkenes represent one of the most straightforward protocols to build molecular complexity due to the simultaneous construction of two vicinal bonds cross π-bond of alkenes. It is extremely attractive yet challenging to control the stereochemistry outcome of this event. Over the past years, visible-light and Ni-catalyzed asymmetric difunctionalizations of alkenes provide an environmental benign and promising solution for the construction of saturated carbon centers with the control of regio- and enantioselectivity. In this Concept, the initiative and progress of regio- and enantioselective difunctionalizations of alkenes enabled by visible-light and nickel catalysis has been summarized. Moreover, further efforts and directions for the development of visible-light mediated Ni-catalyzed asymmetric difunctionalizations of alkenes has been discussed.

2.
Angew Chem Int Ed Engl ; 63(23): e202403073, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38567830

RESUMEN

Catalytic methods allowing for the reliable prediction and control of diverse regioselectivity along with the control of enantioselectivity to access different regio- and enantiomers by switching the least reaction parameters are one of the most attractive ways in organic synthesis, which provide access to diverse enantioenriched architectures from identical starting materials. Herein, a Co-catalyzed regiodivergent and enantioselective reductive hydroalkylation of 1,3-dienes with aldehydes has been achieved, furnishing different enantioenriched homoallylic alcohol architectures in good levels of enantioselectivity. The reaction features the switch of regioselectivity tuned by the selection of proton source. The use of an acid as proton source provided asymmetric 1,2-hydroalkylation products under reductive conditions, yet asymmetric 4,3-hydroalkylation products were obtained with silane as hydride source. This catalytic protocol allows for the access of homoallylic alcohols with two continuous saturated carbon centers in good levels of regio-, diastereo-, and enantioselectivity.

3.
Int J Mol Sci ; 24(4)2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36834972

RESUMEN

Cisplatin is a widely used standard chemotherapy for various cancers. However, cisplatin treatment is associated with severe ototoxicity. Fucoidan is a complex sulfated polysaccharide mainly derived from brown seaweeds, and it shows multiple bioactivities such as antimicrobial, anti-inflammatory, anticancer, and antioxidant activities. Despite evidence of the antioxidant effects of fucoidan, research on its otoprotective effects remains limited. Therefore, the present study investigated the otoprotective effects of fucoidan in vitro using the mouse cochlear cell line UB/OC-2 to develop new strategies to attenuate cisplatin-induced ototoxicity. We quantified the cell membrane potential and analyzed regulators and cascade proteins in the apoptotic pathway. Mouse cochlear UB/OC-2 cells were pre-treated with fucoidan before cisplatin exposure. The effects on cochlear hair cell viability, mitochondrial function, and apoptosis-related proteins were determined via flow cytometry, Western blot analysis, and fluorescence staining. Fucoidan treatment reduced cisplatin-induced intracellular reactive oxygen species production, stabilized mitochondrial membrane potential, inhibited mitochondrial dysfunction, and successfully protected hair cells from apoptosis. Furthermore, fucoidan exerted antioxidant effects against oxidative stress by regulating the Nrf2 pathway. Therefore, we suggest that fucoidan may represent a potential therapeutic agent for developing a new otoprotective strategy.


Asunto(s)
Antineoplásicos , Ototoxicidad , Polisacáridos , Animales , Ratones , Antineoplásicos/farmacología , Antineoplásicos/toxicidad , Antioxidantes/farmacología , Apoptosis , Cisplatino/toxicidad , Ototoxicidad/tratamiento farmacológico , Ototoxicidad/metabolismo , Polisacáridos/farmacología , Polisacáridos/uso terapéutico , Especies Reactivas de Oxígeno/metabolismo
4.
Angew Chem Int Ed Engl ; 62(7): e202215779, 2023 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-36515409

RESUMEN

Functionalizing specific positions on a saturated alkyl molecule is a key challenge in synthetic chemistry. Herein, a ligand-controlled regiodivergent alkylations of alkyl bromides at different positions by Ni-catalyzed alkyl-alkyl cross-electrophile coupling with the second alkyl bromides has been developed. The reaction undergoes site-selective isomerization on one alkyl bromides in a controlled manner, providing switchable access to diverse alkylated structures at different sites of alkyl bromides. The reaction occurs at three similar positions with excellent chemo- and regioselectivity, representing a remarkable ligand tuned reactivity between alkyl-alkyl cross-coupling and nickel migration along the hydrocarbon side chain. This reaction offers a catalytic platform to diverse saturated architectures by alkyl-alkyl bond-formation from identical starting materials.

5.
Molecules ; 25(13)2020 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-32640539

RESUMEN

Excessive levels of reactive oxygen species (ROS) lead to mitochondrial damage and apoptotic cell death in gentamicin-induced ototoxicity. 2,3,4',5-Tetrahydroxystilbene-2-O-ß-d-glucoside (THSG), a bioactive constituent, isolated from Polygonum multiflorum Thunb., exhibits numerous biological benefits in treating aging-related diseases by suppressing oxidative damage. However, its protective effect on gentamicin-induced ototoxicity remains unexplored. Therefore, here, we aimed to investigate the otoprotective effect of THSG on gentamicin-induced apoptosis in mouse cochlear UB/OC-2 cells. We evaluated the effect of gentamicin and THSG on the ROS level, superoxide dismutase (SOD) activity, mitochondrial membrane potential, nuclear condensation, and lactate dehydrogenase (LDH) release, and the expression of apoptosis-related proteins was assessed to understand the molecular mechanisms underlying its preventive effects. The findings demonstrated that gentamicin increased ROS generation, LDH release, and promoted apoptotic cell death in UB/OC-2 cells. However, THSG treatment reversed these effects by suppressing ROS production and downregulating the mitochondrial-dependent apoptotic pathway. Additionally, it increased the SOD activity, decreased the expression of apoptosis-related proteins, alleviated the levels of the apoptotic cells, and impaired cytotoxicity. To the best of our knowledge, this is the first study to demonstrate that THSG could be a potential therapeutic option to attenuate gentamicin-induced ototoxicity.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/metabolismo , Apoptosis/efectos de los fármacos , Gentamicinas/efectos adversos , Glucósidos/farmacología , Mitocondrias/efectos de los fármacos , Ototoxicidad/prevención & control , Estilbenos/farmacología , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Fallopia multiflora/química , Fallopia multiflora/metabolismo , Gentamicinas/farmacología , Gentamicinas/toxicidad , L-Lactato Deshidrogenasa/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Mitocondrias/metabolismo , Ototoxicidad/complicaciones , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/metabolismo
6.
Zhongguo Dang Dai Er Ke Za Zhi ; 15(7): 563-8, 2013 Jul.
Artículo en Zh | MEDLINE | ID: mdl-23866280

RESUMEN

OBJECTIVE: To investigate whether the genetic polymorphism, upstream variable number of tandem repeats (uVNTR), in the monoamine oxidase A (MAOA) gene, is associated with major depressive disorder (MDD) in adolescents and to test whether there is gene-environment interaction between MAOA-uVNTR polymorphism and stressful life events (SLEs). METHODS: A total of 394 Chinese Han subjects, including 187 adolescent patients with MDD and 207 normal students as a control group, were included in the study. Genotyping was performed by SNaP-shot assay. SLEs in the previous 12 months were evaluated. The groups were compared in terms of the frequency distributions of MAOA-uVNTR genotypes and alleles using statistical software. The binary logistic regression model of gene-environment interaction was established to analyze the association of the gene-environment interaction between MAOA-u VNTR genotypes and SLEs with adolescent MDD. RESULTS: The distribution profiles of MAOA-u VNTR genotypes and alleles were not related to the onset of MDD, severity of depression, comorbid anxiety and suicidal ideation/behavior/attempt in adolescents. The gene-environment interaction between MAOA-u VNTR genotypes and SLEs was not associated with MDD in male or female adolescents. CONCLUSIONS: It is not proven that MAOA-u VNTR polymorphism is associated with adolescent MDD. There is also no gene-environment interaction between MAOA-u VNTR polymorphism and SLEs that is associated with adolescent MDD.


Asunto(s)
Trastorno Depresivo Mayor/genética , Interacción Gen-Ambiente , Acontecimientos que Cambian la Vida , Repeticiones de Minisatélite , Monoaminooxidasa/genética , Polimorfismo Genético , Adolescente , Femenino , Genotipo , Humanos , Modelos Logísticos , Masculino
7.
Ying Yong Sheng Tai Xue Bao ; 33(9): 2397-2404, 2022 Sep.
Artículo en Zh | MEDLINE | ID: mdl-36131655

RESUMEN

Soil fungi are important components of belowground biodiversity and play important roles in soil carbon and nutrient cycling. We investigated fungal communities in the top soil (0-10 cm) of 22 Pinus massoniana forests in the Three Gorges Reservoir Region using high-throughput sequencing technique. We found that Ascomycota and Basidiomycota were the dominant fungi phyla, and Eurotiales, Russulales, and Tremellales were the most abundant fungi orders. The dominant functional groups in P. massoniana forests were saprophytic fungi, ectomycorrhizal fungi, and ericoid mycorrhizal fungi. Results of redundancy analysis showed that environmental variables but not spatial variables were the main drivers of soil fungal community structure across the 22 P. massoniana forests, which suggested that habitat filtering rather than dispersal limitation shaped soil fungal community structure. Aboveground biomass, soil conductivity, available phosphorus, soil bulk density, carbon to nitrogen ratio, nitrate concentration, and proportion of slit were the main factors explaining the variation in soil fungal community structure. It should be noted that the key factors influencing different fungal functional groups differed across forests.


Asunto(s)
Basidiomycota , Micobioma , Micorrizas , Pinus , Carbono , Bosques , Hongos , Nitratos , Nitrógeno , Fósforo , Suelo/química , Microbiología del Suelo
8.
Int J Mol Med ; 49(5)2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35348190

RESUMEN

Gentamicin is an important aminoglycoside antibiotic used in the treatment of gram­negative bacterial infections, but nephrotoxicity and ototoxicity reduce its utility. The autophagy pathway is involved in damage of auditory hair cells. With the aim of developing new strategies for attenuating gentamicin ototoxicity, the present study investigated the otoprotective mechanism of 2,3,4',5­tetrahydroxystilbene­2­O­ß­D-glucoside (THSG) in vitro using the mouse cochlear cell line UB/OC­2. MTT assay demonstrated that gentamicin reduced UB/OC­2 cell viability and western blotting showed that gentamicin upregulated autophagy­related proteins, such as Beclin, autophagy related 5 and LC3­II. THSG significantly attenuated gentamicin­induced cytotoxicity, clearly reduced LDH release observed by LDH assay and decreased the expression of autophagy­related proteins. Reverse­transcription­quantitative (RT­q) PCR and western blotting showed that THSG against gentamicin­induced autophagy via suppressing the expression of Sesn2, at both the mRNA and protein level and a possible involvement of AMP­activated protein kinase (AMPK)/mTOR signaling response. Collectively, the present study demonstrated that THSG decreased gentamicin­induced ototoxicity in UB/OC­2 cochlear cells via the autophagic signaling in regulating Sesn2/AMPK/mTOR pathway. These results suggested that THSG might be a new therapeutic agent with the potential to attenuate gentamicin ototoxicity.


Asunto(s)
Ototoxicidad , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Autofagia , Gentamicinas/toxicidad , Glucósidos , Ratones , Ototoxicidad/tratamiento farmacológico , Ototoxicidad/etiología , Estilbenos , Serina-Treonina Quinasas TOR/metabolismo
9.
In Vivo ; 36(3): 1095-1105, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35478148

RESUMEN

BACKGROUND/AIM: Gentamicin has been widely prescribed since the last two decades despite its ototoxicity and nephrotoxicity. Bisdemethoxycurcumin (BDMC) is an affordable and safe curcuminoid with medicinal properties. We aimed to understand the effects of BDMC on the gentamicin-induced hair cell damage in mouse cochlear UB/OC-2 cells, in order to elucidate the therapeutic potential of BDMC against gentamicin-induced ototoxicity. MATERIALS AND METHODS: We quantified the cell membrane potential and examined the regulators and cascade proteins in the intrinsic pathway of hair cell apoptosis. Mouse cochlear UB/OC-2 cells were treated with BDMC before exposure to gentamicin. The effects of BDMC on hair cell viability, mitochondrial function, and apoptosis-related proteins were examined by flow cytometry, western blot, and fluorescent staining. RESULTS: Our results revealed that BDMC reversed gentamicin-mediated cycle arrest at the G2/M phase, stabilizing the mitochondrial membrane potential, decreasing cleaved caspase proteins, and successfully reversing hair cell apoptosis. CONCLUSION: BDMC is a potential agent for reducing gentamicin-induced ototoxicity.


Asunto(s)
Gentamicinas , Ototoxicidad , Animales , Apoptosis , Diarilheptanoides/farmacología , Gentamicinas/toxicidad , Ratones , Ototoxicidad/tratamiento farmacológico , Ototoxicidad/etiología , Ototoxicidad/prevención & control
10.
J Chin Med Assoc ; 85(5): 617-626, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35286283

RESUMEN

BACKGROUND: Taxifolin is a flavanonol with efficacious cytoprotective properties, such as anti-inflammatory, antioxidant, anticancer, hepatoprotective, and nephroprotective effects. However, the potential protective effects of taxifolin against gentamicin-induced ototoxicity have not been confirmed. In this study, the possible mechanisms underlying the effects of taxifolin on gentamicin-induced death of UB/OC-2 cochlear cells were investigated. METHODS: Mouse cochlear UB/OC-2 cells with or without taxifolin pretreatment were exposed to gentamicin, and the effects on cytotoxicity, reactive oxygen species (ROS) production, mitochondrial permeability transition, and apoptotic marker expression were examined using biochemical techniques, flow cytometry, western blotting, and fluorescent staining. RESULTS: Little or no apparent effect of taxifolin on cell viability was observed at concentrations less than 40 µM. Further investigations showed that gentamicin significantly inhibited cell viability in a concentration-dependent manner. Pretreatment with taxifolin attenuated gentamicin-induced lactate dehydrogenase release, as well as cellular cytotoxicity. In addition, taxifolin significantly prevented gentamicin-induced cell damage by decreasing ROS production, stabilizing mitochondrial membrane potential, and downregulating the mitochondrial pathway of apoptosis. CONCLUSION: In summary, pretreatment with taxifolin is effective for mitigating gentamicin-induced apoptotic cell death mediated by the mitochondrial pathway. Our data suggest that taxifolin provides a new approach to combat gentamicin-induced ototoxicity.


Asunto(s)
Ototoxicidad , Animales , Apoptosis , Regulación hacia Abajo , Gentamicinas/toxicidad , Ratones , Quercetina/análogos & derivados , Especies Reactivas de Oxígeno/metabolismo
11.
Biomolecules ; 10(3)2020 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-32197448

RESUMEN

Oxidative stress plays a critical role in the pathogenesis of hearing loss, and 2,3,4',5-tetrahydroxystilbene-2-O-ß-D-glucoside (THSG) exerts antioxidant effects by inhibiting reactive oxygen species (ROS) generation. With the aim of developing new therapeutic strategies for oxidative stress, this study investigated the protective mechanism of THSG in vitro using a normal mouse cochlear cell line (UB/OC-2). The THSG and ascorbic acid have similar free radical scavenger capacities. H2O2, but not THSG, reduced the UB/OC-2 cell viability. Moreover, H2O2 might induce apoptosis and autophagy by inducing morphological changes, as visualized by microscopy. As evidenced by Western blot analysis and monodansylcadaverine (MDC) staining, THSG might decrease H2O2-induced autophagy. According to a Western blotting analysis and Annexin V/PI and JC-1 staining, THSG might protect cells from H2O2-induced apoptosis and stabilize the mitochondrial membrane potential. Furthermore, THSG enhanced the translocation of nucleus factor erythroid 2-related factor 2 (Nrf2) into the nucleus and increased the mRNA and protein expression of antioxidant/detoxifying enzymes under H2O2-induced oxidative stress conditions. Collectively, our findings demonstrate that THSG, as a scavenging agent, can directly attenuate free radicals and upregulate antioxidant/detoxifying enzymes to protect against oxidative damage and show that THSG protects UB/OC-2 cells from H2O2-induced autophagy and apoptosis in vitro.


Asunto(s)
Antioxidantes/metabolismo , Autofagia/efectos de los fármacos , Cóclea/metabolismo , Glucósidos/farmacología , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Estilbenos/farmacología , Animales , Peróxido de Hidrógeno/farmacología , Ratones
12.
ACS Appl Mater Interfaces ; 8(45): 30722-30734, 2016 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-27786455

RESUMEN

Prostate cancer is one of the leading causes of cancer death in adult men and is a multistage disease with therapeutic challenges of local recurrent advanced tumors and distant metastatic disease. CD44 is a multifunctional and multistructural cell surface glycoprotein that is involved in cell-cell interactions, cell proliferation, and cell migration. In the study, we produced negatively charged and biocompatible hyaluronic acid-based nanoparticles as a therapeutic system for targeting CD44-positive cancer cells. Subsequently, we confirmed the delivery of bioactive epigallocatechin-3-gallate and site-specific inhibition of prostate tumor growth. In this study, hyaluronic acid-based nanoparticles successfully encapsulated epigallocatechin-3-gallate and were efficiently internalized into cancer cells via CD44 ligand receptor recognition, induced cell cycle arrest at G2/M phase, and inhibited prostate cancer cell growth. Furthermore, in vivo assays indicated that these nanoparticles specifically bind CD44 receptors and increase apoptosis of cancer cells, leading to significant decreases in prostate tumor activity and tumor tissue inflammation.


Asunto(s)
Nanopartículas , Línea Celular Tumoral , Sistemas de Liberación de Medicamentos , Humanos , Receptores de Hialuranos , Ácido Hialurónico , Masculino , Neoplasias de la Próstata
13.
Chem Biol Interact ; 231: 119-26, 2015 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-25643584

RESUMEN

The insulin-like growth factor-1 receptor (IGF-1R) plays a pivotal role in transformation, growth, and survival of glioblastoma multiforme (GBM) cells, and has emerged as a general and promising target for cancer treatment. In this study, we examined the anti-tumor effects of CHM-1, a synthetic 6,7-methylenedioxy substituted 2-phenyl-4-quinolone derivative, on GBM cells in vitro and in vivo. CHM-1 selectively blocked IGF-1R auto-phosphorylation, with an ability to distinguish between IGF-1R and related tyrosine kinase receptors, such as insulin receptor (IR), epidermal growth factor receptor (EGFR), platelet-derived growth factor receptor (PDGFR), and fibroblast growth factor receptor (FGFR). Further investigation revealed that, the phosphorylation of ERK1/2 as well as Akt was inhibited in CHM-1 treated GBM8401 cells possibly through the selective blockage of IGF-1R auto-phosphorylation. Our study also showed that p.o. treatment with the hydrophilic dihydrogen phosphate CHM-1P reduced the tumor volumes of the GBM8401 derived tumors in mouse brain and also prolonged the survival rate. The results provided potential opportunities for effective chemotherapy for GBM.


Asunto(s)
Antineoplásicos/uso terapéutico , Proliferación Celular/efectos de los fármacos , Dioxoles/uso terapéutico , Glioblastoma/tratamiento farmacológico , Quinolonas/uso terapéutico , Receptor IGF Tipo 1/antagonistas & inhibidores , Animales , Antineoplásicos/farmacología , Línea Celular Tumoral , Dioxoles/farmacología , Femenino , Glioblastoma/metabolismo , Glioblastoma/patología , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ratones Endogámicos BALB C , Ratones SCID , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Quinolonas/farmacología , Receptor IGF Tipo 1/metabolismo , Transducción de Señal/efectos de los fármacos
14.
J Agric Food Chem ; 61(40): 9638-44, 2013 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-24001127

RESUMEN

Yellow camellia, with its golden yellow flowers, is rare in the world. Most studies of yellow camellia have focused on its ornamental properties; however, there are fewer published studies on its medical values. The purpose of this study was to define the chemical constituents and the biological potential of the water extract of leaves in six species of yellow camellia. The data showed that Camellia murauchii had significantly higher total catechins and total polyphenol content than others; Camellia euphlebia had the highest total amino acids and γ-aminobutyric acid. The results indicated that Camellia tunghinensis exhibited the highest free radical scavenging capacity and showed potent anticancer activities. Camellia nitidissima had stronger inhibitory effect than other species on fatty acid synthesis. In addition to catechins, 3-p-coumaroylquinic acid, kaempferol-3-O-glucoside, and quercetin-3-O-glucoside were detected in C. tunghinensis using liquid chromatography-tandem mass spectrometry. Taken together, yellow camellias possess biological activity and are worthy of continued study.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Camellia/química , Extractos Vegetales/farmacología , Aminoácidos/análisis , Antioxidantes/análisis , Neoplasias de la Mama/metabolismo , Cafeína/análisis , Catequina/análisis , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Femenino , Flavonoides/análisis , Flores/química , Glucósidos , Humanos , Quempferoles/análisis , Monosacáridos/análisis , Hojas de la Planta/química , Polifenoles/análisis , Quercetina/análogos & derivados , Espectrometría de Masas en Tándem , Ácido gamma-Aminobutírico/análisis
15.
J Agric Food Chem ; 61(26): 6366-75, 2013 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-23777448

RESUMEN

Demethoxycurcumin (DMC), curcumin (Cur), and bisdemethoxycurcumin (BDMC) are major forms of curcuminoids found in the rhizomes of turmeric. This study examined the effects of three curcuminoid analogues on breast cancer cells. The results revealed that DMC demonstrated the most potent cytotoxic effects on breast cancer MDA-MB-231 cells. Compared with estrogen receptor (ER)-positive or HER2-overexpressing breast cancer cells, DMC demonstrated the most efficient cytotoxic effects on triple-negative breast cancer (TNBC) cells. However, nonmalignant MCF-10A cells were unaffected by DMC treatment. The study showed that DMC activated AMPK in TNBC cells. Once activated, AMPK inhibited eukaryotic initiation factor 4E-binding protein-1 (4E-BP1) signaling and mRNA translation via mammalian target of rapamycin (mTOR) and decreased the activity and/or expression of lipogenic enzymes, such as fatty acid synthase (FASN) and acetyl-CoA carboxylase (ACC). DMC also targeted multiple AMPK downstream pathways. Among these, the dephosphorylation of Akt is noteworthy because it circumvents the feedback activation of Akt that results from mTOR inhibition. Moreover, DMC suppressed LPS-induced IL-6 production, thereby blocking subsequent Stat3 activation. In addition, DMC also sustained epidermal growth factor receptor (EGFR) activation by suppressing the phosphatases, PP2a and SHP-2. These results suggest that DMC is a potent AMPK activator that acts through a broad spectrum of anti-TNBC activities.


Asunto(s)
Anticarcinógenos/farmacología , Carcinogénesis/efectos de los fármacos , Curcumina/análogos & derivados , Metabolismo Energético/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Proteínas Quinasas Activadas por AMP/química , Proteínas Quinasas Activadas por AMP/metabolismo , Línea Celular Tumoral , Curcumina/farmacología , Diarilheptanoides , Activadores de Enzimas/farmacología , Femenino , Humanos , Neoplasias de la Mama Triple Negativas/metabolismo , Neoplasias de la Mama Triple Negativas/prevención & control
16.
J Agric Food Chem ; 60(34): 8427-34, 2012 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-22849866

RESUMEN

Curcumin (Cur), demethoxycurcumin (DMC), and bisdemethoxycurcumin (BDMC) are major forms of curcuminoids found in the rhizomes of turmeric. This study examined the effects of three curcuminoid analogues on prostate cancer cells. The results revealed that DMC demonstrated the most efficient cytotoxic effects on prostate cancer PC3 cells. DMC activated AMPK and in turn decreased the activity and/or expression of lipogenic enzymes, such as fatty acid synthase (FASN) and acetyl-CoA carboxylase (ACC). AICAR, an AMPK activator, and DMC down-regulated heat shock protein (HSP) 70 and increased the activity of the pro-apoptotic effector, caspase-3. In addition, DMC sustained epidermal growth factor receptor (EGFR) activation by suppressing the phosphatases PP2a and SHP-2. DMC also increased the interaction between EGFR and Cbl and induced the tyrosine phosphorylation of Cbl. The results suggest that DMC may have antitumor effects on prostate cancer cells via AMPK-induced down-regulation of HSP70 and EGFR.


Asunto(s)
Curcumina/análogos & derivados , Receptores ErbB/metabolismo , Proteínas HSP70 de Choque Térmico/metabolismo , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/patología , Proteínas Quinasas Activadas por AMP , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacología , Antineoplásicos Fitogénicos/farmacología , Caspasa 3/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Curcuma/química , Curcumina/farmacología , Diarilheptanoides , Regulación hacia Abajo , Acido Graso Sintasa Tipo I/metabolismo , Humanos , Masculino , Fosforilación/efectos de los fármacos , Neoplasias de la Próstata/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 11/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-cbl/metabolismo , Ribonucleótidos/farmacología
17.
J Agric Food Chem ; 60(25): 6399-407, 2012 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-22670709

RESUMEN

Prostate cancer is one of the leading causes of cancer death in men in Western countries. Epidemiological studies have linked the consumption of fruits and vegetables to a reduced risk of prostate cancer, and small fruits are particularly rich sources of many active phytochemical stilbenes, such as pterostilbene. As a constituent of small fruits such as grapes, berries, and their products, pterostilbene is under intense investigation as a cancer chemopreventive agent. Using the p53 wild type LNCaP and p53 null PC3 cells, we found that treatment with pterostilbene resulted in dose-dependent inhibition of cellular proliferation, which suggested that the interaction of pterostilbene with the p53 might not fully explain its inhibitory effect on proliferation. In this study, we found that pterostilbene activated AMPK in both p53 positive and negative human prostate cancer cells. Pterostilbene-activated AMPK decreased the activity and/or expression of lipogenic enzymes, such as fatty acid synthase (FASN) and acetyl-CoA carboxylase (ACC). Interestingly, the resolution between apoptosis and growth arrest following AMPK activation is greatly influenced by p53 status. In p53 positive LNCaP cells, pterostilbene blocked the progression of cell cycle at G1 phase by inducing p53 expression and further up-regulating p21 expression. However, pterostilbene induced apoptosis in p53 negative PC3 cells. Our results suggest that pterostilbene may be a functional chemopreventive agent and that dietary exposure to pterostilbene would be helpful for antiprostate cancer activity.


Asunto(s)
Ciclo Celular/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Lipogénesis/efectos de los fármacos , Neoplasias de la Próstata/fisiopatología , Proteínas Quinasas/metabolismo , Estilbenos/farmacología , Proteína p53 Supresora de Tumor/metabolismo , Quinasas de la Proteína-Quinasa Activada por el AMP , Línea Celular Tumoral , Activación Enzimática/efectos de los fármacos , Humanos , Masculino , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/enzimología , Proteínas Quinasas/genética , Proteína p53 Supresora de Tumor/genética
18.
J Agric Food Chem ; 58(8): 4786-93, 2010 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-20218616

RESUMEN

While fatty acid synthase (FASN) has been shown to be expressed in many human solid tumors, FASN has also been identified in preneoplastic lesions. HER2, which has also been identified in preneoplastic breast lesions, has been shown to upregulate FASN expression. Osthole, an active constituent isolated from the fruit of Cnidium monnieri (L.) Cusson, a traditional Chinese medicine, was found to be effective in suppressing FASN expression in HER2-overexpressing breast cells. Osthole preferentially inhibited proliferation and induced apoptosis in HER2-overexpressing cancer cells. Moreover, osthole inhibited the phosphorylation of Akt and mTOR. The use of Akt-overexpression revealed that the modulation of Akt and mTOR was required for osthole-induced FASN suppression. Finally, we showed that osthole could enhance paclitaxel-induced cytotoxicity in HER2-overexpressing cancer cells. These results suggested that osthole has the potential to advance as chemopreventive or chemotherapeutic agent for cancers that overexpress HER2.


Asunto(s)
Neoplasias de la Mama/enzimología , Cumarinas/farmacología , Ácido Graso Sintasas/antagonistas & inhibidores , Genes erbB-2 , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Ácido Graso Sintasas/metabolismo , Humanos , Serina-Treonina Quinasas TOR
19.
J Agric Food Chem ; 58(3): 1584-92, 2010 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-19928762

RESUMEN

Resveratrol functions as an agonist for estrogen receptor (ER)-mediated transcription. However, other researchers have reported that resveratrol decreases proliferation of breast cancer cells that are either ER-positive or ER-negative, which suggests that the interaction of resveratrol with the ER may not fully explain its inhibitory effect on proliferation. Similar to those effects associated with caloric restriction (CR), resveratrol has multiple beneficial activities, such as increased life span and delay in the onset of diseases associated with aging. One key enzyme thought to be activated during CR is the AMP-activated kinase (AMPK), a sensor of cellular energy levels. The suppression of nonessential energy expenditure by activated AMPK along with the CR mimetic and antiproliferative properties of resveratrol has led us to hypothesize that resveratrol activity might have an important role in the activation of AMPK. Here, we show that resveratrol activated AMPK in both ER-positive and ER-negative breast cancer cells. Once activated, AMPK inhibited 4E-BP1 signaling and mRNA translation via mammalian target of rapamycin (mTOR). Moreover, we also found that AMPK activity mediated by resveratrol in cancer cells was due to inducing the expression of Sirtuin type 1 (SIRT1) via elevation in the cellular NAD(+)/NADH in ER-positive cells. To our knowledge, we demonstrate here for the first time that resveratrol induces the expression of SIRT1 protein in human cancer cells. These observations raise the possibility that SIRT1 functions as a novel upstream regulator for AMPK signaling and may additionally modulate tumor cell proliferation. Targeting SIRT1/AMPK signaling by resveratrol may have potential therapeutic implications for cancer and age-related diseases.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Proliferación Celular/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Biosíntesis de Proteínas/efectos de los fármacos , Sirtuina 1/metabolismo , Estilbenos/farmacología , Proteínas Quinasas Activadas por AMP/genética , Animales , Línea Celular Tumoral , Activación Enzimática/efectos de los fármacos , Femenino , Expresión Génica/efectos de los fármacos , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/fisiopatología , Resveratrol , Transducción de Señal/efectos de los fármacos , Sirtuina 1/genética , Estilbenos/administración & dosificación
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