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1.
Zhongguo Zhong Yao Za Zhi ; 48(16): 4295-4301, 2023 Aug.
Artículo en Chino | MEDLINE | ID: mdl-37802856

RESUMEN

Ziziphi Spinosae Semen(ZSS) is an edible TCM derived from the dried ripe seeds of Ziziphus jujube Mill. var. spinosa(Bunge)Hu ex H. F. Chou(Rhamnaceae), which has the effects of nourishing the heart, tonifying the liver, calming the heart, tranquilizing the mind, arresting sweating, and promoting fluid production, and is widely used in the treatment and health care of diseases related to cardiovascular, nervous, and immune systems. Jujuboside B(JuB), one of the main active ingredients of ZSS, possesses various pharmacological effects with application values. This paper reviewed the chemical structure and pharmacological effects of JuB. JuB has sedative, hypnotic, antitumor, anti-platelet, anti-inflammatory, and other biological activities, which shows the potential thera-peutic effects on insomnia, tumors, coronary artery disease, airway inflammation, and liver injury. However, there are some limitations to the results of current studies. More comprehensive studies, including basic research and clinical trials, need to be carried out to provide more reliable evidence.


Asunto(s)
Medicamentos Herbarios Chinos , Saponinas , Trastornos del Inicio y del Mantenimiento del Sueño , Ziziphus , Humanos , Medicamentos Herbarios Chinos/farmacología , Saponinas/farmacología , Hipnóticos y Sedantes , Ziziphus/química
2.
Acta Biomater ; 166: 552-566, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37236575

RESUMEN

Immune checkpoint blockade (ICB) therapy has shown great potential in the treatment of malignant tumors, but its therapeutic effect on glioblastoma (GBM) is unsatisfactory because of the low immunogenicity and T cell infiltration, as well as the presence of blood-brain barrier (BBB) that blocks most of ICB agents to the GBM tissues. Herein, we developed a biomimetic nanoplatform of AMNP@CLP@CCM for GBM-targeted photothermal therapy (PTT) and ICB synergistic therapy by loading immune checkpoint inhibitor CLP002 into the allomelanin nanoparticles (AMNPs) and followed by coating cancer cell membranes (CCM). The resulting AMNP@CLP@CCM can successfully cross the BBB and deliver CLP002 to GBM tissues due to the homing effect of CCM. As a natural photothermal conversion agent, AMNPs are used for tumor PTT. The increased local temperature by PTT not only enhances BBB penetration but also upregulates the PD-L1 level on GBM cells. Importantly, PTT can effectively stimulate immunogenic cell death to induce tumor-associated antigen exposure and promote T lymphocyte infiltration, which can further amplify the antitumor immune responses of GBM cells to CLP002-mediated ICB therapy, resulting in significant growth inhibition of the orthotopic GBM. Therefore, AMNP@CLP@CCM has great potential for the treatment of orthotopic GBM by PTT and ICB synergistic therapy. STATEMENT OF SIGNIFICANCE: The effect of ICB therapy on GBM is limited by the low immunogenicity and insufficient T-cell infiltration. Here we developed a biomimetic nanoplatform of AMNP@CLP@CCM for GBM-targeted PTT and ICB synergistic therapy. In this nanoplatform, AMNPs are used as both photothermal conversion agents for PTT and nanocarriers for CLP002 delivery. PTT not only enhances BBB penetration but also upregulates the PD-L1 level on GBM cells by increasing local temperature. Additionally, PTT also induces tumor-associated antigen exposure and promotes T lymphocyte infiltration to amplify the antitumor immune responses of GBM cells to CLP002-mediated ICB therapy, resulting in significant growth inhibition of the orthotopic GBM. Thus, this nanoplatform holds great potential for orthotopic GBM treatment.


Asunto(s)
Glioblastoma , Nanopartículas , Humanos , Fototerapia/métodos , Antígeno B7-H1 , Melaninas , Glioblastoma/terapia , Glioblastoma/patología , Biomimética , Inmunoterapia , Nanopartículas/uso terapéutico , Línea Celular Tumoral
3.
Sci Rep ; 12(1): 18620, 2022 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-36329041

RESUMEN

Magnetic tunnel junction (MTJ) with magnesium oxide (MgO) tunnel barrier is the core element of spin transfer torque-based magnetic random access memory. For the application in the space environment, the total ionizing dose radiation effects on MTJs need to be evaluated. In this work, the MTJs were exposed to X-ray radiation with different doses of up to 10 Mrad(Si). Measurements of current induced magnetization switching (CIMS) behavior of these MTJs were performed before and after radiation. The results show negligible changes in the tunneling magnetoresistance and current switching properties after 8 Mrad(Si) X-ray radiation. However, with a total dose of 9 Mrad(Si), a significant reduction in junction resistance of a fairly large number of MTJs was observed, which showed characteristics of MTJ breakdown. Moreover, in this study, all experimental MTJs became functionally disabled due to MgO breakdown under 10 Mrad(Si) X-ray radiation. The CoFeB/MgO/CoFeB interface microstructure was observed using X-ray photoelectron spectroscopy and high-resolution transmission electron microscopy (HRTEM). Interfacial structural results indicate that the MgO degradation and breakdown behavior caused by X-ray ionizing radiation can give rise to radiation-induced oxygen vacancies across the tunnel barrier oxide layer.

4.
Artículo en Inglés | MEDLINE | ID: mdl-35047049

RESUMEN

The prevalence and risk factors of intracranial atherosclerotic stenosis (ICAS) located in the anterior circulation (AC) and posterior circulation (PC) has been scarcely noted in the general population. We aimed to determine ICAS prevalence and risk factor profile of AC and PC in a representative population. Data were from the China Hypertension Survey of Beijing. In total, 4800 people aged 35 years or older were enrolled in this subsurvey for ICAS, and 3954 participants were eligible for analysis. ICAS was assessed by transcranial Doppler. The prevalence of ICAS in AC was much greater than that in PC (11.9% vs. 4.2%), and subjects with ICAS in PC were 3.9 years older than those with ICAS in AC. Multivariable logistics regression showed that the odds of hypertension and diabetes increased by 79% (OR: 1.79, 95% CI: 1.40-2.27) and 35% (OR: 1.35, 95% CI: 1.04-1.75) in those with AC vascular lesions and by 3.35 times (OR: 3.35, 95% CI: 2.49-4.50) and 71% (OR: 1.71, 95% CI: 1.19-2.46) in those with PC vascular lesions compared with those without vascular lesions. Most modifiable vascular risk factors for ICAS appeared to exert similar magnitudes of risk for PC to AC lesions.

5.
Sci Total Environ ; 806(Pt 1): 150540, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34583074

RESUMEN

Phosphorus contamination in urbanized bays has been a major concern because the bay restoration is often hindered by complex P sources and behaviors. This study examined the spatiotemporal changes of P species and exchange potential in/between the water and sediment of the Jiaozhou Bay. The results indicated that dissolved P (TDP) and inorganic P (DIP) in the water ranged from 7.8-128.7 and 1.8-14.1 µg/L, respectively; while total P (TP) in the sediment ranged from 213.4-638.7 mg/kg. The TDP and DIP concentrations in the water were high in winter and low in summer, and generally decreased from northeastern or northern areas to southwestern or southern areas mainly due to phytoplankton bloom cycles and riverine and wastewater inputs. TP in the sediment was lower in the northwestern area due to solid dilution effect by the settlement of settled coarser suspended particles. Changes in aquatic geochemical conditions from rivers to bay caused P accumulation in estuarine sediment, with higher P partition in organic fraction (40%). Compared to the estuarine sediment, higher fractions of P were associated with carbonate (34%) and iron oxide (17%) minerals in the bay sediment. Equilibrium P concentrations at zero sorption (EPC0) were 4.1-149.8 µg/L, which was substantially higher than the DIP concentration, demonstrating P release potential from the sediment. In addition, the P release potential was high in the northeastern area while P partition coefficient or buffer intensity (Kd) was high in the northwestern area. EPC0 was significantly positively correlated with soluble and exchangeable P in the sediment while Kd was significantly negatively correlated. These results can provide improved insights into P behaviors in an urbanized bay, particularly the P release potential and spatiotemporal change.


Asunto(s)
Bahías , Contaminantes Químicos del Agua , China , Monitoreo del Ambiente , Sedimentos Geológicos , Fósforo/análisis , Agua , Contaminantes Químicos del Agua/análisis
6.
Arch Biochem Biophys ; 676: 108158, 2019 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-31629712

RESUMEN

Esophageal squamous cell carcinoma (ESCC) is one of the prevalent and deadly cancers worldwide, especially in Eastern Asia. Our present study revealed that the expression of IL-8 was increased in radiation therapy resistance of ESCC cells. Targeted inhibition of IL-8 by its neutralization antibody (anti-IL-8) can re-sensitize ESCC cells to radiation therapy and suppress the expression of proliferating cell nuclear antigen (PCNA). IL-8 can regulate the expression of PCNA via modulating its mRNA stability and promoter activity. Mechanistically, IL-8 can regulate the expression of miR-27b-5p, which can directly bind with 3'UTR of PCNA to decrease its mRNA stability. Further, anti-IL-8 can decrease the expression of transcription factor YY1, which can bind with the promoter of PCNA to increase its transcription. Taken together, our data revealed that IL8 can regulate the radiation resistance of ESCC cells and expression of PCNA. It suggested that targeted inhibition of IL-8 may improve the clinical treatment efficiency of radio therapy.


Asunto(s)
Carcinoma de Células Escamosas de Esófago/patología , Interleucina-8/metabolismo , Antígeno Nuclear de Célula en Proliferación/genética , Tolerancia a Radiación , Línea Celular Tumoral , Humanos , Tolerancia a Radiación/genética , Transcripción Genética , Factor de Transcripción YY1/metabolismo
7.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 36(10): 1241-1246, 2016 10.
Artículo en Chino | MEDLINE | ID: mdl-30641014

RESUMEN

Objective To observe the effects of Bushen Tiaojing Recipe (BTR) on the counts of survival preantral follicles and the bone morphogenetic protein receptor II (BMPR II )/activin receptor- like kinase 6-drosophila mothers against decapentaplegic proteins (ALK6-Smads) signal pathway in oocytes cultured in vitro, and to study its mechanism for improving the quality of oocytes. Methods Prean- tral follicles were mechanically isolated from 65 female 12-day old healthy Kunming mice, which were inoculated by normal rats' serum (as the control group) , high, medium, low dose BTR containing serums (as Shen-supplementing groups) , high dose BTR containing serum + K02288 (as the inhibitor group) , respectively. All were cultured by common method in vitro. On the 6th day the counts of survival preantral follicles were compared between each Shen-supplementing group and the control group respectively. mR- NA expressions of BMPR II, ALK6, Smad1 , Smad5, and Smad8 were detected by Real-time fluorescence quantitative PCR. The protein expressions of indices mentioned above and phospho-Smadl/5/8 (p- Smadl/5/8) were detected by cellular immunofluorescence test. Results Compared with the control group, the quantity of survival preantral follicles increased in the high dose BTR containing serum group; mRNA expressions of BMPR II, ALK6, Smad5, and Smad8 were elevated, protein expressions of indi- ces mentioned above and p-Smadl/5/8 were increased in the 3 Shen-supplementing groups (P <0. 05) ; mRNA and protein expressions of Smad1 were increased in high and medium dose BTR containing serum groups (P<0.05). Compared with the high dose BTR containing serum group, protein expressions of Smad1/5/8 were reduced in the inhibitor group (P <0.05). Conclusion BTR could elevate the quantity of survival preantral follicles cultured in vitroand improve the quality of oocytes, which might be possibly as- sociated to regulating the BMPR II/ALK6-Smads signal pathway in oocytes.


Asunto(s)
Receptores de Proteínas Morfogenéticas Óseas de Tipo II , Medicamentos Herbarios Chinos , Oocitos , Animales , Receptores de Proteínas Morfogenéticas Óseas de Tipo 1/efectos de los fármacos , Receptores de Proteínas Morfogenéticas Óseas de Tipo 1/metabolismo , Receptores de Proteínas Morfogenéticas Óseas de Tipo II/efectos de los fármacos , Receptores de Proteínas Morfogenéticas Óseas de Tipo II/metabolismo , Medicamentos Herbarios Chinos/farmacología , Femenino , Ratones , Oocitos/efectos de los fármacos , Oocitos/metabolismo , Folículo Ovárico , Ratas , Transducción de Señal , Proteínas Smad/efectos de los fármacos , Proteínas Smad/metabolismo
8.
Mol Med Rep ; 12(5): 7463-70, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26458817

RESUMEN

Human umbilical cord mesenchymal stem cells (hUC­MSCs) hold great potential in the search for therapies to treat refractory diseases, including rheumatoid arthritis (RA), due to their potential regenerative ability and extensive source. However, the role of hUC­MSCs in vivo and the repair mechanisms for RA remain to be fully elucidated. The present study aimed to determine whether hUC­MSCs exert immunomodulatory effects and have anti­inflammatory capabilities in the treatment of embolisms. Following the transplantation of hUC­MSCs into collagen type Ⅱ­induced arthritic (CIA) model rats, magnetic resonance imaging (MRI) in vivo was performed, and the levels of interleukin (IL)­1, IL­17, tumor necrosis factor (TNF)­α, vascular endothelial growth factor (VEGF), tissue factor (TF), CD4+CD25+ T cells (Treg) and antithrombin (AT) were measured. Bromodeoxyuridine staining was performed for histopathological examinations. As revealed by immunofluorescence and MRI experiments, the injected hUC­MSCs preferentially migrated to the inflammatory joint sites of the rats. The Treg cell percentage and AT levels in the hUC­MSC­treated group were markedly increased, whereas the levels of IL­1, IL­17, TNF­α, VEGF and TF were decreased compared with those in the CIA model group. The values determined for these parameters in the hUC­MSC­treated group returned to approximately the identical values as those of the control group on day 35 post­therapy. Superparamagnetic iron oxide nanoparticles (SPIONs) may serve as an effective, non­invasive method for tracking transplanted cells in vivo. The present study provided direct evidence that hUC­MSCs in the CIA rat model migrated to the inflammatory joint sites, effectively promoting recovery from collagen type II damage and thereby improving the immune­associated prothrombotic state.


Asunto(s)
Artritis Experimental/terapia , Artritis Reumatoide/terapia , Trasplante de Células Madre Mesenquimatosas , Animales , Artritis Experimental/sangre , Artritis Experimental/inmunología , Artritis Reumatoide/sangre , Artritis Reumatoide/inmunología , Proteínas Aviares , Movimiento Celular , Rastreo Celular , Células Cultivadas , Pollos , Colágeno Tipo II , Citocinas/sangre , Femenino , Miembro Posterior/patología , Humanos , Células Madre Mesenquimatosas/fisiología , Ratas , Ratas Sprague-Dawley , Linfocitos T Reguladores/inmunología
9.
J Ethnopharmacol ; 155(3): 1583-8, 2014 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-25093547

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Gecko, a kind of reptile, has been widely used as a traditional Chinese medicine to treat various diseases including cancer in China for thousands of years. The aim of this study was to investigate the anti-tumor effect of AG (aqueous extracts of fresh gecko) on human hepatocellular carcinoma cell Bel-7402 in vitro and mouse H22 hepatocellular in vivo. Further to underlie the molecular mechanism of AG inducing the differentiation of Bel-7402 cells. MATERIALS AND METHODS: AG was obtained by water extracting method and qualitatively analyzed through High Performance Liquid Chromatography. The total protein concentration of AG was measured by BCA (bicinchoninic acid disodium) assay. The anti-tumor activities in vivo were analyzed through H22 (mouse hepatocellular carcinoma cell line H22) tumor xenografts mice. The cytotoxic activity of AG on Bel-7402 cells was evaluated by MTT assays. AFP (alpha fetoprotein) was detected by radioimmunoassay. ALB (albumin), ALP (alkaline phosphatase) and γ-GT (γ-glutamyl transpeptidase) were detected by biochemical methods with commercial kits. While morphological changes were observed through an inverted microscope. Moreover, the expression level of the proteins involved in MAPK (mitogen-activated protein kinase) signal pathway which was closely related to cellular differentiation was assessed by Western blot. RESULTS: AG showed obviously anti-tumor activity in vivo and anti-proliferative activity on Bel-7402 cells in vitro both dose-dependently. The number of clones of Bel-7402 cells treated with AG reduced and the cells were displaying differentiation state such as relatively bigger size and dispersed growth. The biochemical function markers of the cells were significantly changed after being treated with AG. The data showed that AFP secretion of the cells decreased 42.5%, ALB secretion increased 58.9%, the activity of ALP and γ-GT markedly decreased 67.0% and 48.5% separately when the concentration of AG was 10µl/ml, and those effects were all in a dose-dependent manner. The major original and phosphorylated signal proteins (ERK1/2 (extracellular sigal-regualted kinase 1/2), P38 (p38 MAPK) and JNK1/2 (c-Jun N-terminal kinase 1/2)) involved in MAPK signal pathway were measured and the results showed that AG activated the ERK1/2 of Bel-7402 cells. CONCLUSIONS: AG has anti-tumor activity in vivo and inhibits Bel-7402 cell proliferation in vitro through inducing cell differentiation, and the mechanism involves the activation of ERK1/2.


Asunto(s)
Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Mezclas Complejas/farmacología , Mezclas Complejas/uso terapéutico , Lagartos , Animales , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/metabolismo , Diferenciación Celular/efectos de los fármacos , Línea Celular Tumoral , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Medicina Tradicional China , Ratones Endogámicos ICR , Ensayos Antitumor por Modelo de Xenoinjerto
10.
Zhong Yao Cai ; 36(7): 1050-2, 2013 Jul.
Artículo en Chino | MEDLINE | ID: mdl-24417135

RESUMEN

OBJECTIVE: To compare the inhibitory effects of fresh gecko crude extract and its hydrolysate on H22 transplanted tumor in mice. METHODS: The content of soluble nitrogen (SN-TCA index) was used to determine the degree of enzymolysis. The hydrolysate of gecko was obtained from fresh gecko crude extract by pepsin and papain hydrolyzing. H22 transplanted tumor mouse models were established and divided into negative group, positive group,crude extract group and hydrolysate group. RESULTS: The inhibition rate of the H22 tumor-bearing mice was 29.17%, 48.99% respectively for the crude extract group and the hydrolysate group. The inhibition rate of hydrolysate group and the negative group were significantly different (P < 0.05). The spleen and thymus index for the crude extract group and the hydrolysate group didn't show different compared with the negative group. CONCLUSION: The crude extract of the fresh gecko and the hydrolysate can inhibit the growth of the H22 transplanted tumor. The enzymolysis by pepsin and papain can increase the antitumor activity of the crude extract of fresh gecko.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias Hepáticas Experimentales/patología , Lagartos , Materia Medica/farmacología , Hidrolisados de Proteína/farmacología , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/aislamiento & purificación , Línea Celular Tumoral , Modelos Animales de Enfermedad , Femenino , Hidrólisis , Materia Medica/administración & dosificación , Materia Medica/aislamiento & purificación , Ratones , Ratones Endogámicos ICR , Pepsina A/metabolismo , Hidrolisados de Proteína/administración & dosificación , Bazo/efectos de los fármacos , Timo/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
11.
Zhongguo Gu Shang ; 21(11): 824-7, 2008 Nov.
Artículo en Chino | MEDLINE | ID: mdl-19143242

RESUMEN

OBJECTIVE: To observe and assess the effect of manipulation on knee cartilaginous recovery with knee osteoarthritis (OA) by using magnetic resonance (MR). METHODS: Fifty cases which were suffering from knee OA involved this retrospective study. They were matched-pairs into 2 groups according to their gender, age and severity. Treated with manipulation once a week in one year for manipulation group patients, compared with those orally use with 500 mg glucosamine sulfate (GS) three times per day. Knee cartilage MR were performed before treatment and on 3, 6, 12 months after treatment, the maximum defect diameter and volume of knee cartilage were assessed with Noyes Score. RESULT: Both Noyes Score declined in the two groups. But Noyes Score of the manipulation group significantly decreased 6 months after treatment, the same tendency was observed just 12 months after treatment in another group. The maximum defect diameter of knee cartilage began to diminish at 3 months after treatment in the manipulation group, grew significantly at 6 and 12 months after treatment compared with before treatment. In the GS group, there was no significantly deference in the maximum defect diameter of knee cartilage between after and before treatment. The volume of knee cartilage in manipulation group was greater than the GS group at 3, 6, 12 months after treatment and significantly increased at 6 months after treatment and grew 58 percent 12 months after treatment. The volume of knee cartilage in GS group had no significantly change, though had a tendency to increase. CONCLUSION: Manipulation is effective to treatment of knee osteoarthritis by decreasing the maximum defect diameter and increasing the volume of knee cartilage.


Asunto(s)
Cartílago/lesiones , Manipulaciones Musculoesqueléticas/métodos , Osteoartritis de la Rodilla/terapia , Anciano , Cartílago/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/tratamiento farmacológico , Radiografía , Estudios Retrospectivos , Resultado del Tratamiento
12.
Proc Natl Acad Sci U S A ; 103(9): 3153-8, 2006 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-16492761

RESUMEN

Rapid quantitative methods for characterizing small molecules, peptides, proteins, or RNAs in a broad array of cellular assays would allow one to discover new biological activities associated with these molecules and also provide a more comprehensive profile of drug candidates early in the drug development process. Here we describe a robotic system, termed the automated compound profiler, capable of both propagating a large number of cell lines in parallel and assaying large collections of molecules simultaneously against a matrix of cellular assays in a highly reproducible manner. To illustrate its utility, we have characterized a set of 1,400 kinase inhibitors in a panel of 35 activated tyrosine-kinase-dependent cellular assays in dose-response format in a single experiment. Analysis of the resulting multidimensional dataset revealed subclusters of both inhibitors and kinases with closely correlated activities. The approach also identified activities for the p38 inhibitor BIRB796 and the dual src/abl inhibitor BMS-354825 and exposed the expected side activities for Glivec/STI571, including cellular inhibition of c-kit and platelet-derived growth factor receptor. This methodology provides a powerful tool for unraveling the cellular biology and molecular pharmacology of both naturally occurring and synthetic chemical diversity.


Asunto(s)
Fosfotransferasas/antagonistas & inhibidores , Fosfotransferasas/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Robótica/métodos , Animales , Automatización , Línea Celular , Bases de Datos Factuales , Evaluación Preclínica de Medicamentos/métodos , Ratones , Fosfotransferasas/genética , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/aislamiento & purificación , Reproducibilidad de los Resultados , Relación Estructura-Actividad , Factores de Tiempo
13.
Int J Cardiol ; 106(2): 285-8, 2006 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-16183151

RESUMEN

To investigate effects of supplementation of folic acid on the expression of adhesion molecules VCAM-1 in the aortas of rats with hyperhomocysteinemia. Thirty male SD rats (200 +/- 20 g) were invided into 3 groups (n = 10 for each group): control group(Control), high Met group(Met) and Met plus Folate group(Met + Folate), fed. for 45 days. Plasma Hcy levels were higher with the high-methionine diet (140.68 +/- 36.87 micromol/L vs 6.47 +/- 1.10 micromol/L in control rats) an effect which was reduced by folate. Respectively, the aortic expression of adhesion molecules VCAM-1 at protein and mRNA levels were higher in the Met groups than those in the control groups or the Met + Folate groups. A high methionine diet for 45 days was sufficient to induce hyperhomocysteinemia. Folate supplementation prevented elevation of Hcy levels in the blood, and reduced expression of the adhesion molecule VCAM-1. Hyperhomocysteinemia is now regarded as one of the important risk factors for cardiovascular and cerebralvascular disorders.[Welch GN, Loscalzo J. Homocysteine and atherothrombosis. N Engl J Med 1998; 38(15):1042-50.] Several plausible mechanisms for Hcy-induecd atherosclerosis have been proposed. These include endothelial dysfunction, enhancement of oxidative stress, reduction in NO bioavailability, and augmentation of thrombus formation.[Holven KB, Holm T, Aukrust P, et al. Effect of folic acid treatment on endothelium-dependent vasodilation and nitric oxide-derived end products in hyperhomocysteinemic subjects . Am J Med 2001;110(7):536-42; Guba SC, Fonseca V, Fink LM. Hyperhomocysteinemia and thrombosis. Semin Thromb Hemost 1999;25(3):291-309.] However, the precise molecular mechanism is still unclear. Recent reports have suggested a role for inflammatory processes in the pathogenesis of atherosclerosis.[Gerard C, Rollins BJ. Chemokines and disease. Nat Immunol 2001;2(2):108-15.] Dysfunction of endothelial cells is the key process promoting inflammatory reactions. On injury, endothlial cells are capable of producing various cytokines that participate in inflammatory reactions in the arterial wall. Although results from in vitro studies suggest that Hcy, at pathophysiological concentrations, stimulates chemokine expression in vascular cells, it is unknown whether hyperhomocysteinemia can initiate similar changes, leading to enhanced momocyte adhesion/binding to the vascular endothelium in vivo.[Zeng X, Dai J, Remick DG, Wang X. Homocysteine mediated expression and secretion of monocyte chemoattractant protein-1 and interleukin-8 in human monocytes. Circ Res 2003;93(4):311-20.] On the basis of the potential pathogenic role of chemokines in atherogenesis, the objective of the present study was to investigate that homocsteine may exert its effect in part though adhesion molecules VCAM-1 and that folic acid supplementation may downregulate these inflammatory responses. Male Sprague-Dawley rats (bred from animal centers of Tongji Medical College, Huazhong Science and Technology University) aged 8 weeks were divided into 3 groups(n=10 for each group) and maintained for 45 days on the following diets before the experiments: (1) regular diet; (2) high-metheionine diet, consisting of regular diet plus 1.7% methionine; and (3) high-methionine plus folate -rich diet, consisting of regular diet plus 1.7% methionine and 0.006% folate.[Boisvert WA, Curtiss LK, Terkeltaub RA. Interleukin-8 and its receptor CXCR2 in atherosclerosis. Immunol Res 2000;21(2-3):129-d37.] Plasma and serum samples wee colleced and stored at -80 degrees C after 45 days until analysis. The plasma homocysteine concentration of rats in three groups were determined by high-pressue liquid chromatography. To detect the endothelial expression of adhesion molecules VCAM-1, the thoracic aorta was isolated and dived into segments. These segments were immersion-fixed in 10% neutral-buffered formalin overlight and then embedded in paraffin. Sequential 5 mum paraffin-embedded cross sections were prepared. Immunohistochemical analyisis was performed to detect vascular cell adhesion molecule(VCAM)-1, The fixed cryosections were immediately blcked in 10% horse serum and phosphate baffered saline(PBS) at room temperature for 30 min. Goat polyclonal andibodies against rat VCAM-1(Santa Cruz Biotechnology) were diluted 1:100 in PBS and incubated with the cryosections for 1 h of room temperature. After three washes, the sections were incubated with biotin-conjugated rabbit anti-goat immunoglobulins(Dako) at 1:250 dilution in PBS. After three washes, the samples were mounted in 90% glycerol-PBS. Photographs were taken by use of a light microscope at a mignification of x200.


Asunto(s)
Aorta/metabolismo , Ácido Fólico/farmacología , Hiperhomocisteinemia/metabolismo , Molécula 1 de Adhesión Celular Vascular/biosíntesis , Animales , Masculino , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley
14.
Bioorg Med Chem Lett ; 15(5): 1475-8, 2005 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-15713410

RESUMEN

A series of dihydroxyphenylpyrazole compounds were identified as a unique class of reversible Hsp90 inhibitors. The crystal structures for two of the identified compounds complexed with the N-terminal ATP binding domain of human Hsp90alpha were determined. The dihydroxyphenyl ring of the compounds fits deeply into the adenine binding pocket with the C2 hydroxyl group forming a direct hydrogen bond with the side chain of Asp93. The pyrazole ring forms hydrogen bonds to the backbone carbonyl of Gly97, the hydroxyl group of Thr184 and to a water molecule, which is present in all of the published HSP90 structures. One of the identified compounds (G3130) demonstrated cellular activities (in Her-2 degradation and activation of Hsp70 promoter) consistent with the inhibition of cellular Hsp90 functions.


Asunto(s)
Proteínas HSP90 de Choque Térmico/química , Pirazoles/química , Línea Celular , Línea Celular Tumoral , Cristalografía por Rayos X , Evaluación Preclínica de Medicamentos , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Humanos , Enlace de Hidrógeno , Modelos Moleculares , Estructura Molecular , Estructura Terciaria de Proteína , Pirazoles/farmacología , Relación Estructura-Actividad , Factores de Tiempo
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