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1.
J Plant Res ; 134(1): 55-76, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33251557

RESUMEN

Microsoroideae is the third largest of the six subfamilies of Polypodiaceae, containing over 180 species. These ferns are widely distributed in the tropical and subtropical regions of the Old World and Oceania. We documented the spore ornamentation and integrated these data into the latest phylogenetic hypotheses, including a sampling of 100 taxa representing each of 17 major lineages of microsoroid ferns. This enabled us to reconstruct the ancestral states of the spore morphology. The results show verrucate ornamentation as an ancestral state for Goniophlebieae and Lecanoptereae, globular for Microsoreae, and rugulate surface for Lepisoreae. In addition, spore ornamentation can be used to distinguish certain clades of the microsoroid ferns. Among all five tribes, Lecanoptereae show most diversity in spore surface ornamentation.


Asunto(s)
Helechos , Polypodiaceae , Helechos/genética , Filogenia , Esporas
2.
Biomed Chromatogr ; 35(12): e5227, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34388856

RESUMEN

The aim of this study was to investigate drug interactions of L-dopa/carbidopa with catechin and green tea essence in rabbits following the simultaneous administration via an intramuscular injection of catechin or via an intragastric route for green tea essence with L-dopa/carbidopa. The results indicated that catechin at doses of 10, 20 and 50 mg/kg increased the area under the plasma concentration-time curve from time zero to the time of the last quantifiable concentration (AUC0-t ) of L-dopa by about 69, 78 and 42%, respectively. The metabolic ratios of the AUC0-t for 3-O-methyldopa (3-OMD)/L-dopa significantly decreased by about 56, 68 and 76% (P < 0.05), respectively. In addition, a single dose of 5/1.25 mg/kg L-dopa/carbidopa was co-administrated with 150 mg/kg green tea essence via an intragastric route with an oral-gastric tube. Comparing the related pharmacokinetic parameters of L-dopa, the clearance and metabolic ratio of L-dopa decreased by 20 and 19% (P < 0.05), respectively. In conclusion, catechin and green tea essence can significantly affect the metabolism of L-dopa by the catechol-O-methyltransferase (COMT) metabolic pathway. Catechin can enhance L-dopa bioavailability, and both catechin and green tea essence decreased 3-OMD formation. Therefore, catechin and green tea essence may increase L-dopa efficacy for Parkinson's disease treatment.


Asunto(s)
Catequina , Interacciones de Hierba-Droga , Levodopa , Té/química , Animales , Disponibilidad Biológica , Carbidopa/sangre , Carbidopa/química , Carbidopa/farmacocinética , Catequina/metabolismo , Catequina/farmacocinética , Catecol O-Metiltransferasa , Cromatografía Liquida , Levodopa/sangre , Levodopa/química , Levodopa/farmacocinética , Masculino , Conejos , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem , Tirosina/análogos & derivados , Tirosina/sangre , Tirosina/química , Tirosina/farmacocinética
3.
Int J Mol Sci ; 21(8)2020 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-32326308

RESUMEN

Hormones and their receptors play an important role in the development and progression of breast cancer. Hormones regulate the proliferation of breast cancer cells through binding between estrogen or progestins and steroid receptors that may reside in the cytoplasm or be transcriptionally activated as steroid-protein nuclear receptor complexes. However, receptors for nonpeptide hormones also exist in the plasma membrane. Via those receptors, hormones are able to stimulate breast cancer cell proliferation when activated. Integrins are heterodimeric structural proteins of the plasma membrane. Their primary functions are to interact with extracellular matrix proteins and growth factors. Recently, integrin αvß3 has been identified as a receptor for nonpeptide hormones, such as thyroid hormone and dihydrotestosterone (DHT). DHT promotes the proliferation of human breast cancer cells through binding to integrin αvß3. A receptor for resveratrol, a polyphenol stilbene, also exists on this integrin in breast cancer cells, mediating the anti-proliferative, pro-apoptotic action of the compound in these cells. Unrelated activities of DHT and resveratrol that originate at integrin depend upon downstream stimulation of mitogen-activated protein kinase (MAPK, ERK1/2) activity, suggesting the existence of distinct, function-specific pools of ERK1/2 within the cell. This review will discuss the features of these receptors in breast cancer cells, in turn suggesting clinical applications that are based on the interactions of resveratrol/DHT with integrin αvß3 and other androgen receptors.


Asunto(s)
Dihidrotestosterona/metabolismo , Integrina alfaVbeta3/metabolismo , Resveratrol/farmacología , Andrógenos/metabolismo , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Dihidrotestosterona/farmacología , Humanos , Unión Proteica , Receptores Androgénicos/metabolismo , Transducción de Señal/efectos de los fármacos
4.
Mar Drugs ; 16(12)2018 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-30563284

RESUMEN

A marine sesterterpenoid-type natural product, heteronemin, retains anticancer effects. In the current study, we investigate the antitumor mechanism of heteronemin in cholangiocarcinoma cells and further explore its molecular targets. Initially, heteronemin exhibited potent cytotoxic effects against cholangiocarcinoma HuccT1 and SSP-25 cells. In vitro, heteronemin altered the abilities of cell adhesion and cell migration in HuccT1 and SSP-25 cell lines. It repressed messenger ribonucleic acid (mRNA) expression levels of transforming growth factor (TGF)-ß, mothers against decapentaplegic homolog (SMAD) and Myc, whose protein products play important roles in regulating cell growth, angiogenesis, and metastasis. In addition, heteronemin altered several signaling pathways. The results indicate that heteronemin was able to modulate cell adhesion, the expression of extracellular matrix (ECM) receptors, the TGF-ß pathway, cell motility, the membrane integration, metastasis response, matrix metalloproteinase (MMP) remodeling, the regulation of metabolism, sprouting angiogenesis, transcription factors, and vasculogenesis in cholangiocarcinoma cell lines. The results also suggest that it activated multiple signal transduction pathways to induce an anti-proliferation effect and anti-metastasis in cholangiocarcinoma. In conclusion, heteronemin may be used as a potential medicine for anticancer therapy.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Neoplasias de los Conductos Biliares/tratamiento farmacológico , Colangiocarcinoma/tratamiento farmacológico , Transducción de Señal/efectos de los fármacos , Terpenos/farmacología , Animales , Antineoplásicos Fitogénicos/uso terapéutico , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Poríferos/química , ARN Mensajero/metabolismo , Terpenos/uso terapéutico , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo
5.
Int J Mol Sci ; 13(4): 4523-4544, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22605994

RESUMEN

The Pteris cadieri complex displays extensive morphological variation and seems to have originated through hybridization. However, the members of this complex reproduce by apogamy, which usually limits genetic variation. To evaluate the hypotheses of hybrid origins, the pattern of evolution in this species complex is reconstructed. Multiple methodologies were used. Diploids, triploids, and tetraploids were identified by chromosome counts and flow cytometry. Nuclear DNA markers (cytosolic phosphoglucose isomerase gene, PgiC) were used, together with chloroplast DNA markers (atpB-rbcL spacer and rbcL gene) to infer the biparental and maternal lineages of the Pteris cadieri complex. The three cpDNA haplotype groups and five PgiC alleles found in this study indicate that the evolution of the Pteris cadieri complex has been extremely reticulate. Up to 11 taxa belonging to eight morphs were identified. By comparing genetic variation in the Pteris cadieri in two independent areas, Hainan and Taiwan, we inferred that hybridization has occurred independently in different areas. Furthermore, we found evidence for phenological divergence (evergreen and deciduous) within Taiwan. We propose that the Pteris cadieri complex originated from different genetic lineages through multiple hybridizations in different geographical areas, leading to its present morphological diversity.


Asunto(s)
ADN de Cloroplastos/genética , ATPasas de Translocación de Protón/genética , Pteris/clasificación , Pteris/genética , Ribulosa-Bifosfato Carboxilasa/genética , Secuencia de Bases , Evolución Biológica , Quimera/genética , Evolución Molecular , Marcadores Genéticos/genética , Variación Genética , Geografía , Hibridación Genética , Filogenia , Hojas de la Planta/anatomía & histología , Hojas de la Planta/clasificación , Análisis de Secuencia de ADN , Taiwán
6.
J Hand Surg Asian Pac Vol ; 27(4): 649-655, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35965359

RESUMEN

Background: Ultrasonography is often used in the diagnosis of carpal tunnel syndrome (CTS). However, we were unable to find normative data regarding the cross-sectional area (CSA) of the median nerve in the Singapore population as measured by ultrasound. The aims of this study were to establish normative values of the CSA of the median nerve at the carpal tunnel inlet in a healthy population, 5 cm proximal to the carpal tunnel inlet, and to determine if the CSA correlated with side, age, gender or race. Methods: Sixty-nine wrists of 36 healthy subjects with no history of wrist injury or any signs and symptoms of CTS were examined. The CSA of the median nerve at the carpal tunnel inlet and 5 cm proximal to the carpal tunnel inlet was determined using ultrasound by a trained operator. Results: The mean CSA of the median nerve at the carpal tunnel inlet was 6.41 mm2 (SD 2.18 mm2). These were not significantly different from the values for mean CSA obtained 5 cm proximal to the carpal tunnel inlet. We did not find any correlation between the CSA of the median nerve and age, gender or race. Conclusions: The mean CSA of the median nerve at the carpal tunnel inlet in normal subjects in Singapore was found to be lower than other Asian populations. Wide variations of the median nerve CSA at the carpal tunnel inlet exists in the literature, and this is probably due to the heterogeneity of the study methodology and population. Level of Evidence: Level III (Diagnostic).


Asunto(s)
Síndrome del Túnel Carpiano , Nervio Mediano , Bahías , Síndrome del Túnel Carpiano/diagnóstico por imagen , Antebrazo/diagnóstico por imagen , Humanos , Nervio Mediano/diagnóstico por imagen , Singapur
7.
Sci Rep ; 12(1): 13352, 2022 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-35922458

RESUMEN

Climate change has caused severe impacts on ecosystems and biodiversity globally, especially to vulnerable mountain ecosystems; the summits bear the brunt of such effects. Therefore, six summits in Taiwan were monitored based on a standardized multi-summit approach. We used both statistical downscaling of climate data and vegetation cover data to calculate climate niches to assess the impacts of climate change. Two indicators, thermophilic and moist-philic, were applied to evaluate the overall response of vegetation dynamics. The results revealed that potential evapotranspiration increased significantly and led to a declining tendency in monthly water balance from 2014 to 2019. The general pattern of species richness was a decline. The difference in plant cover among the three surveys showed an inconsistent pattern, although some dominant species expanded, such as the dwarf bamboo Yushania niitakayamensis. The thermophilic indicator showed that species composition had changed so that there were more thermophilic species at the three lowest summits. The moist-philization indicator showed a decline of humid-preferred species in the latest monitoring period. Although total precipitation did not decrease, our results suggest that the variability in precipitation with increased temperature and potential evapotranspiration altered alpine vegetation composition and could endanger vulnerable species in the future.


Asunto(s)
Cambio Climático , Ecosistema , Altitud , Biodiversidad , Plantas
8.
Cells ; 11(19)2022 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-36231010

RESUMEN

Oral cancer is a fatal disease, and its incidence in Taiwan is increasing. Thyroid hormone as L-thyroxine (T4) stimulates cancer cell proliferation via a receptor on integrin αvß3 of plasma membranes. It also induces the expression of programmed death-ligand 1 (PD-L1) and cell proliferation in cancer cells. Thyroid hormone also activates ß-catenin-dependent cell proliferation in cancer cells. However, the relationship between PD-L1 and cancer proliferation is not fully understood. In the current study, we investigated the role of inducible thyroid hormone-induced PD-L1-regulated gene expression and proliferation in oral cancer cells. Thyroxine bound to integrin αvß3 to induce PD-L1 expressions via activation of ERK1/2 and signal transducer and activator of transcription 3 (STAT3). Inactivated STAT3 inhibited PD-L1 expression and nuclear PD-L1 accumulation. Inhibition of PD-L1 expression reduced ß-catenin accumulation. Furthermore, nuclear PD-L1 formed a complex with nuclear proteins such as p300. Suppression PD-L1 expression by shRNA blocked not only expression of PD-L1 and ß-catenin but also signal transduction, proliferative gene expressions, and cancer cell growth. In summary, thyroxine via integrin αvß3 activated ERK1/2 and STAT3 to stimulate the PD-L1-dependent and ß-catenin-related growth in oral cancer cells.


Asunto(s)
Antígeno B7-H1 , Neoplasias de la Boca , Antígeno B7-H1/metabolismo , Humanos , Integrina alfaVbeta3/metabolismo , Neoplasias de la Boca/metabolismo , Proteínas Nucleares/metabolismo , ARN Interferente Pequeño , Factor de Transcripción STAT3/metabolismo , Transducción de Señal , Hormonas Tiroideas , Tiroxina/farmacología , beta Catenina/metabolismo
9.
Front Cell Dev Biol ; 10: 862045, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36111333

RESUMEN

Reduced fertility associated with normal aging may reflect the over-maturity of oocytes. It is increasingly important to reduce aging-induced infertility since recent trends show people marrying at later ages. 2,3,5,4'-Tetrahydroxystilbene-2-O-ß-D-glucoside (THSG), a polyphenol extracted from Polygonum multiflorum, has been reported to have anti-inflammatory and anti-aging properties. To evaluate whether THSG can reduce aging-related ovarian damage in a female mouse model of aging, THSG was administered by gavage at a dose of 10 mg/kg twice weekly, starting at 4 weeks of age in a group of young mice. In addition, the effect of THSG in a group of aged mice was also studied in mice starting at 24 weeks of age. The number of oocytes in the THSG-fed group was higher than in the untreated control group. Although the percentage of secondary polar bodies (PB2) decreased during aging in the THSG-fed group, it decreased much more slowly than in the age-matched control group. THSG administration increased the quality of ovaries in young mice becoming aged. Western blotting analyses also indicated that CYP19, PR-B, and ER-ß expressions were significantly increased in 36-week-old mice. THSG also increased oocyte numbers in aged mice compared to mice without THSG fed. Studies of qPCR and immunohistochemistry (IHC) analyses of ovaries in the aged mice groups were conducted. THSG increased gene expression of anti-Müllerian hormone (AMH), a biomarker of oocyte number, and protein accumulation in 40-week-old mice. THSG increased the expression of pgc1α and atp6, mitochondrial biogenesis-related genes, and their protein expression. THSG also attenuated the fading rate of CYP11a and CYP19 associated with sex hormone synthesis. And THSG maintains a high level of ER-ß expression, thereby enhancing the sensitivity of estrogen. Our findings indicated that THSG increased or extended gene expression involved in ovarian maintenance and rejuvenation in young and aged mice. On the other hand, THSG treatments significantly maintained oocyte quantity and quality in both groups of young and aged mice compared to each age-matched control group. In conclusion, THSG can delay aging-related menopause, and the antioxidant properties of THSG may make it suitable for preventing aging-induced infertility.

10.
J Biomed Sci ; 18: 8, 2011 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-21251245

RESUMEN

BACKGROUND: Alzheimer's disease (AD) is the most common cause of dementia characterized by progressive cognitive impairment in the elderly people. The most dramatic abnormalities are those of the cholinergic system. Acetylcholinesterase (AChE) plays a key role in the regulation of the cholinergic system, and hence, inhibition of AChE has emerged as one of the most promising strategies for the treatment of AD. METHODS: In this study, we suggest a workflow for the identification and prioritization of potential compounds targeted against AChE. In order to elucidate the essential structural features for AChE, three-dimensional pharmacophore models were constructed using Discovery Studio 2.5.5 (DS 2.5.5) program based on a set of known AChE inhibitors. RESULTS: The best five-features pharmacophore model, which includes one hydrogen bond donor and four hydrophobic features, was generated from a training set of 62 compounds that yielded a correlation coefficient of R = 0.851 and a high prediction of fit values for a set of 26 test molecules with a correlation of R² = 0.830. Our pharmacophore model also has a high Güner-Henry score and enrichment factor. Virtual screening performed on the NCI database obtained new inhibitors which have the potential to inhibit AChE and to protect neurons from Aß toxicity. The hit compounds were subsequently subjected to molecular docking and evaluated by consensus scoring function, which resulted in 9 compounds with high pharmacophore fit values and predicted biological activity scores. These compounds showed interactions with important residues at the active site. CONCLUSIONS: The information gained from this study may assist in the discovery of potential AChE inhibitors that are highly selective for its dual binding sites.


Asunto(s)
Acetilcolinesterasa/química , Inhibidores de la Colinesterasa/química , Modelos Biológicos , Modelos Moleculares , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/enzimología , Precursor de Proteína beta-Amiloide/metabolismo , Inhibidores de la Colinesterasa/farmacocinética , Bases de Datos Factuales , Humanos , Neuronas/enzimología
11.
Phytochemistry ; 187: 112776, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33933828

RESUMEN

Transformation of 15-ene steviol (ent-13-hydroxy-kaur-15-en-19-oic acid) by growth cultures of Aspergillus niger BCRC 32720, Cunninghamella bainieri ATCC 9244, and Mortierella isabellina ATCC 38063 was conducted to generate various derivatives for the development of bioactive compounds. Four previously undescribed compounds along with six known compounds were obtained. The newly identified isolates were characterized using 1D and 2D NMR, IR, and HRESIMS, and three compounds were further confirmed by X-ray crystallographic analyses. Subsequently, the effects of 15-ene steviol and its derivatives on lipopolysaccharide (LPS)-induced cytokine production by THP-1 cells were examined, with dexamethasone used as a positive control. Results indicated that most of the tested compounds showed lower inhibitory effects than those detected in the dexamethasone-treated group, except that 15-ene steviol showed better effects than dexamethasone on the reduction of LPS-induced monocyte chemoattractant protein (MCP)-1, -2, and -3 release. Three specialized products similarly showed better effects than dexamethasone on the inhibition of LPS-induced secretion of regulated on activation, normal T cell expressed and secreted (RANTES). Moreover, none of the tested compounds showed any cytotoxicity or triggered cell apoptosis, and none affected the protein integrity of toll-like receptor 4 (TLR4) or MyD88, suggesting that these compounds may exert the anti-inflammatory activity downstream of membrane-associated TLR4 and MyD88 molecules.


Asunto(s)
Cunninghamella , Aspergillus niger , Diterpenos de Tipo Kaurano , Hongos
12.
Food Chem Toxicol ; 136: 111092, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31883986

RESUMEN

Nano-diamino-tetrac (NDAT), a tetraiodothyroxine deaminated nano-particulated analog, has shown to inhibit expression of pro-inflammatory genes. NDAT inhibits expression of programmed death-ligand 1 (PD-L1). On the other hand, in addition to inhibiting inflammatory effect, the stilbene, resveratrol induces expression of cyclooxygenase-2 (COX-2) and its accumulation. Sequentially, inducible COX-2 complexes with p53 and induces p53-dependent anti-proliferation. In current study, we investigated mechanisms involved in combined treatment of NDAT and resveratrol on anti-proliferation in human oral cancer cells. Both resveratrol and NDAT inhibited expression of pro-inflammatory IL-1ß and TNF-α. They also inhibited expression of CCND1 and PD-L1. Both resveratrol and NDAT induced BAD expression but only resveratrol induced COX-2 expression in both OEC-M1 and SCC-25 cells. Combined treatment attenuated gene expression significantly compared with resveratrol treatment in both cancer cell lines. Resveratrol reduced nuclear PD-L1 accumulation which was enhanced by a STAT3 inhibitor, S31-201 or NDAT suggesting that NDAT may inactivate STAT3 to inhibit PD-L1 accumulation. In the presence of T4, NDAT further enhanced resveratrol-induced anti-proliferation in both cancer cell lines. These findings provide a novel understanding of the inhibition of NDAT in thyroxine-induced pro-inflammatory effect on resveratrol-induced anticancer properties.


Asunto(s)
Neoplasias de la Boca/fisiopatología , Poliglactina 910/farmacología , Resveratrol/farmacología , Tiroxina/análogos & derivados , Antígeno B7-H1/genética , Antígeno B7-H1/inmunología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ciclina D1/genética , Ciclina D1/metabolismo , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/inmunología , Sinergismo Farmacológico , Expresión Génica , Humanos , Neoplasias de la Boca/genética , Neoplasias de la Boca/inmunología , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/inmunología , Tiroxina/farmacología
13.
J Biomol Struct Dyn ; 26(6): 731-40, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19385701

RESUMEN

Several neurodegenerative diseases, such as Alzheimer's, Parkinson's, and Huntington's diseases, are associated with amyloid fibrils formed by different polypeptides. Recently, the atomic structure of the amyloid-forming peptide GGVVIA from the C-terminal hydrophobic segment of amyloid-beta (Abeta) peptide has been determined and revealed a dry, tightly self-complementing structure between two beta-sheets, termed as "steric zipper". In this study, several all-atom molecular dynamics simulations with explicit water were conducted to investigate the structural stability and aggregation behavior of the GGVVIA oligomers with various sizes. The results of our single-layer models suggested that the structural stability of the GGVVIA oligomers increases remarkably with increasing the numbers of beta-strands. We further identified that SH2-ST2 may act as a stable seed in prompting amyloid fibril formations. Our results also demonstrated that hydrophobic interaction is the principle driving force to stabilize and associate the GGVVIA oligomers between beta-strands; while the hydrophobic steric zipper formed via the side chains of V3, V4, and I5 plays a critical role in holding the two neighboring beta-sheets together. Single glycine substitution at V3, V4, and I5 directly disrupted the hydrophobic steric zipper between these two beta-sheets, resulting in the destabilization of the oligomers. Our simulation results provided detailed insights into understanding the aggregation behavior of the GGVVIA oligomers in the atomic level. It may also be helpful for designing new inhibitors able to prevent the fibril formation of Abeta peptide.


Asunto(s)
Péptidos beta-Amiloides/química , Simulación por Computador , Oligopéptidos/química , Fragmentos de Péptidos/química , Secuencia de Aminoácidos , Interacciones Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Conformación Proteica , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína
14.
Chin J Physiol ; 52(5 Suppl): 395-405, 2009 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-20359130

RESUMEN

Serotonin (5-hydroxytryptamin; 5-HT) content has been measured using high-performance liquid chromatography with electrochemical detection (HPLC-ECD). The distributions of 5-HT-containing cells and 5-HT3 receptors have been determined with specific antibodies against 5-HT and 5-HT3 receptors, respectively. The effect of serotonin on acid secretion has been studied using an isolated rat stomach model. It has been shown that 5-HT concentrations in the fundus, mucosal layers of the corpus, remaining layer of the corpus and antrum are approximately 152, 498, 1494 and 972 nmol/mg protein, respectively. The distribution of 5-HT-containing cells is concentrated in the enteric plexus and enterochromaffin (EC) cells in the deep mucosal layer. Immunoreactivity to 5-HT3 receptors is localized in numerous neurons of the myenteric and submucosal plexus and concentrated in the neuronal plasma membrane, submucosa, endocrine cells and lamina propria. In the present study, the effect of 5-HT on gastric acid secretion was investigated on an everted preparation of isolated rat stomach. 5-HT at 1-100 microM reduced acid secretion stimulated by oxotremorine while 10 microM 5-HT did not modify the basal secretion of gastric acid. We further showed that 10 microM 5-HT reduced acid secretion and pepsin output stimulated by oxotremorine, histamine and pentagastrin; among the 5-HT receptors agonists tested, 2-methyl-5-HT (1-10 microM), a 5-HT3 receptor agonist, inhibited oxotremorine-, histamine- and pentagastrin-stimulated acid secretions, and this inhibitory effect was blocked by 1 microM MDL 72222, a specific 5-HT3 receptor antagonist. These results suggest that 5-HT is released from serotoninergic neurons, their processes and EC cells. The effect of 5-HT mediated by 5-HT3 receptors involves distinct neuronal and non-neuronal pathways which modulate gastric acid secretion.


Asunto(s)
Receptores de Serotonina 5-HT3/fisiología , Serotonina/farmacología , Estómago/efectos de los fármacos , Animales , Células Enterocromafines/efectos de los fármacos , Células Enterocromafines/metabolismo , Ácido Gástrico/metabolismo , Histamina/farmacología , Técnicas In Vitro , Masculino , Oxotremorina/farmacología , Pentagastrina/farmacología , Ratas , Ratas Sprague-Dawley , Serotonina/análogos & derivados , Serotonina/metabolismo , Estómago/fisiología , Tropanos/farmacología
15.
PhytoKeys ; 131: 69-81, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31565025

RESUMEN

A new species of Bolbitis, B. lianhuachihensis sp. nov., was found in central Taiwan. It most resembles B. virens var. compacta and B. hainanensis. A phylogenetic tree of Taiwanese and other Asian species of Bolbitis species supports the recognition of the new species. Morphologically, the combination of anastomosing venation and fewer sterile pinnae are critical characters to discriminate B. lianhuachihensis from other Taiwanese Bolbitis species. Bolbitis lianhuachihensis can be further distinguished from B. virens var. compacta and B. hainanensis by having lanceolate sterile pinnae and absent or fewer free veinlets in small areoles of sterile pinnae. The morphological descriptions, illustration, ecology and distribution of the new species are presented. A key to all Taiwanese Bolbitis is also provided.

16.
Artículo en Inglés | MEDLINE | ID: mdl-30915033

RESUMEN

Colorectal cancer is a serious medical problem in Taiwan. New, effective therapeutic approaches are needed. The selection of promising anticancer drugs and the transition from pre-clinical investigations to clinical trials are often challenging. The deaminated thyroid hormone analog (tetraiodothyroacetic acid, tetrac) and its nanoparticulate analog (NDAT) have been shown to have anti-proliferative activity in vitro and in xenograft model of different neoplasms, including colorectal cancers. However, mechanisms involved in tetrac- and NDAT-induced anti-proliferation in colorectal cancers are incompletely understood. We have investigated possible mechanisms of tetrac and NDAT action in colorectal cancer cells, using a perfusion bellows cell culture system that allows efficient, large-scale screening for mechanisms of drug actions on tumor cells. Although integrin αvß3 in K-RAS wild type colorectal cancer HT-29 cells was far less than that in K-RAS mutant HCT116 cells, HT-29 was more sensitive to both tetrac and NDAT. Results also indicate that both tetrac and NDAT bind to tumor cell surface integrin αvß3, and the agents may have different mechanisms of anti-proliferation in colorectal cancer cells. K-RAS status appears to play an important role in drug resistance that may be encountered in treatment with this drug combination.

17.
Food Chem Toxicol ; 133: 110808, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31499123

RESUMEN

The obesity-regulated gene, leptin, is essential for diet. Leptin resistance causes obesity and related diseases. Certain types of diet are able to decrease leptin resistance. However, leptin has been shown to be correlated with inflammation and stimulate proliferation of various cancers. Two synthetic leptin derivatives (mimetics), OB3 and [D-Leu-4]-OB3, show more effective than leptin in reducing obesity and diabetes in mouse models. OB3 inhibits leptin-induced proliferation in ovarian cancer cells. However, effects of these mimetics in hepatocellular carcinoma (HCC) have not been investigated. In the present study, we examined the effects of OB3 and [D-Leu-4]-OB3 on cell proliferation and gene expressions in human HCC cell cultures. In contrast to what was reported for leptin, OB3 and [D-Leu-4]-OB3 reduced cell proliferation in hepatomas. Both OB3 and [D-Leu-4]-OB3 stimulated expression of pro-apoptotic genes. Both compounds also inhibited expressions of pro-inflammatory, proliferative and metastatic genes and PD-L1 expression. In combination with leptin, OB3 inhibited leptin-induced cell proliferation and expressions of pro-inflammation-, and proliferation-related genes. Furthermore, the OB3 peptide inhibited phosphoinositide 3-kinase (PI3K) activation which is essential for leptin-induced proliferation in HCC. These results indicate that OB3 and [D-Leu-4]-OB3 may have the potential to reduce leptin-related inflammation and proliferation in HCC cells.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Expresión Génica/efectos de los fármacos , Leptina/farmacología , Fragmentos de Péptidos/farmacología , Transducción de Señal/efectos de los fármacos , Línea Celular Tumoral , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Humanos , Péptidos y Proteínas de Señalización Intercelular/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Fosfatidilinositol 3-Quinasa/metabolismo , Inhibidores de Proteínas Quinasas/farmacología
19.
Food Chem Toxicol ; 112: 67-75, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29242151

RESUMEN

Cyclooxygenase (COX)-2 has been implicated in cancer development. However, resveratrol-induced nuclear accumulation of COX-2 enhances p53-dependent anti-proliferation in different types of cancers. Treatment with resveratrol leads to phosphorylation and nuclear translocation of mitogen-activated protein kinase (ERK1/2), and accumulation of nuclear COX-2 to complex with pERK1/2 and p53. The consequence is Ser-15 phosphorylation of p53 (pSer15-p53), and induction of anti-proliferation in cancer cells. We investigated the mechanisms by which resveratrol-inducible COX-2 facilitates p53-dependent anti-proliferation in prostate cancer LNCaP cells. Resveratrol treatment caused nuclear accumulation and complexing of ERK1/2, pSer15-p53 and COX-2 which was activated ERK1/2-dependent. Knockdown of SUMO-1 by shRNA also reduced nuclear accumulation of COX-2. Inhibition of nuclear accumulation by the COX-2 specific inhibitor, NS-398, inhibited co-localization of nuclear COX-2 and SUMO-1. Similar results were observed in the PD98059-treated cells. Finally, inhibition of SUMO-1 expression also reduced resveratrol-induced expression of pro-apoptotic genes but increased the expression of proliferative genes. In summary, these results demonstrate that inducible COX-2 associates with phosphorylated ERK1/2 to induce the phosphorylation of Ser-15 in p53 and then complexes with p53 and SUMO-1 which binds to p53-responsive pro-apoptotic genes to enhance their expression. The inhibition of COX-2 expression and activity significantly blocks the pro-apoptotic effect of resveratrol.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Proliferación Celular/efectos de los fármacos , Ciclooxigenasa 2/metabolismo , Neoplasias de la Próstata/patología , Estilbenos/farmacología , Sumoilación , Apoptosis/genética , Western Blotting , Línea Celular Tumoral , Núcleo Celular/metabolismo , Ciclooxigenasa 2/biosíntesis , Inducción Enzimática , Técnicas de Silenciamiento del Gen , Humanos , Sistema de Señalización de MAP Quinasas , Masculino , Microscopía Confocal , Fosforilación , Neoplasias de la Próstata/enzimología , Transporte de Proteínas , ARN Interferente Pequeño/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Resveratrol , Proteína SUMO-1/genética , Proteína SUMO-1/metabolismo , Proteína p53 Supresora de Tumor/metabolismo
20.
Food Chem Toxicol ; 120: 346-355, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30026090

RESUMEN

Leiomyomas (myomas) are the most common benign smooth muscle cell tumor of the myometrium. Resveratrol, a stilbene, has been used as an anti-inflammatory and antitumor agent. In the current study, we investigated the inhibitory effect of resveratrol on the proliferation of primary human myoma cell cultures. Resveratrol arrested cell proliferation via integrin αvß3. It also inhibited integrin αvß3 expression and protein accumulation. Concurrently, constitutive AKT phosphorylation in myoma cells was inhibited by resveratrol. Expressions of proapoptotic genes, such as cyclooxygenase (COX)-2, p21 and CDKN2, were induced by resveratrol in myoma cells. On the other hand, expressions of proliferative (anti-apoptotic) genes were either inhibited, as in BCL2, or unchanged, as in cyclin D1 and proliferating cell nuclear antigen (PCNA). The accumulation of insulin-like growth factor (IGF)-1 receptor (IGF-1R) was inhibited by resveratrol in primary myoma cells. IGF-1-induced cell proliferation was inhibited by co-incubation with resveratrol. Therefore, growth modulation of myoma cells occurs via mechanisms dependent on cross-talk between integrin αvß3 and IGF-1R. Our findings suggest that resveratrol can be considered an alternative therapeutic agent for myomas.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Integrina alfaVbeta3/metabolismo , Leiomioma/patología , Receptor Cross-Talk , Receptor IGF Tipo 1/metabolismo , Estilbenos/farmacología , Neoplasias Uterinas/patología , Femenino , Citometría de Flujo , Humanos , Etiquetado Corte-Fin in Situ , Leiomioma/metabolismo , Fosforilación , Resveratrol , Neoplasias Uterinas/metabolismo
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