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1.
J Ethnopharmacol ; 264: 113126, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32763416

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Postmenopausal osteoporosis is a major bone health issue worldwide. There is an unmet medical need for osteoporosis treatments, a disease which disproportionately impacts women. Exploring botanicals to prevent or treat osteoporosis is currently an interest of investigations. Rhizomes of Davallia mariesii T. Moore ex Baker (Davalliacea) are used an indigenous herbal medicine in Asia for injuries due to fractures, contusions, and strains. AIM OF THE STUDY: In the present study, we investigated the osteogenic effect of the water extract of rhizomes of D. mariesii (DMH) on bone loss induced by an ovariectomy (OVX) in mice and also its impact on osteogenesis in primary human osteoblasts (HObs). Additionally, we performed a quantitative analysis of compounds in the DMH extract. MATERIALS AND METHODS: OVX C57BL/6J mice were orally administrated DMH extract for 12 weeks, and microarchitecture parameters were examined by microcomputed tomography. DMH extract was fractionated in a bio-guided manner, and fractions were isolated to obtain active compounds using HObs. Cell viability was evaluated by an MTT assay. Characteristics of early and late osteogenesis were analyzed by alkaline phosphatase activity and a mineralization assay. Molecular mechanisms were explored by a real-time quantitative PCR. Compounds in the DMH extract were identified and quantified using liquid chromatography tandem mass spectroscopy (LC-MS/MS). RESULTS: DMH improved bone mineral densities of vertebrae and the femur. Through microarchitectural observations, DMH significantly decreased the bone surface/volume ratio and trabecular separation, and also increased the connectivity density in the OVX group. Additionally, DMH inhibited osteoclast differentiation in receptor activator of nuclear factor-κB ligand-induced osteoclasts and increased bone formation in HObs. After bio-guided fractionation and isolation, we found that eriodictyol-7-O-ß-d-glucuronide (2) significantly increased alkaline phosphatase activity, and 5-O-ß-d-(6-O-vanilloylglucopyranosyl)gentisic acid (3) substantially enhanced mineral deposition. In HObs, compound 3 was more potent in upregulating expressions of bone morphogenetic protein-2, bone sialoprotein, osteopontin, osterix, and estrogen receptor-α. The amount of bioactive compound 3 in DMH was 5.68 ±â€¯0.64 mg/g of dry weight according to LC-MS/MS. CONCLUSION: For the first time we report that D. mariesii and its isolated compounds demonstrated potent osteogenic activities. Quantitative results of D. mariesii could be a reference for phytochemical analyses.

2.
Gastroenterology ; 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32777282
3.
Food Funct ; 11(6): 5420-5431, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32475999

RESUMO

Osteogenesis plays a vital role in the maintenance of bone health. Imbalances in osteogenesis influence the onset of several bone loss-associated diseases. The intake of Uraria crinita (Fabaceae) through dietary supplements is advised for childhood bone dysplasia. This botanical provides edible tonics and detoxifiers, and is also used as a folk beverage. We evaluated the osteogenic effects of a 50% ethanol extract of the root of U. crinita on primary human osteoblasts (HObs) and initiated a novel comprehensive phytochemical strategy using liquid chromatography-tandem mass spectrometry (LC-MS/MS) for quality control of this functional food. Two isoflavones, genistein (5) and 5,7-dihydroxy-3',5'-dihydroxyisoflavone (6), increased the alkaline phosphatase activity (differentiation stage); the flavone glycoside vitexin (1), and the phenolic acid salicylic acid (2) enhanced the mineralization (mature stage). The isoflavone 2'-hydroxygenistein (4) possessed high osteogenic potential among the isolated compounds in HObs. It promoted osteogenesis-related stages and upregulated the gene expressions in a dose-dependent manner. The major compounds in the active fraction were quantitatively analyzed via phytochemical fingerprint detection. These LC-MS/MS-based phytochemical perspectives can act as reference standards in developing food supplements from U. crinita.

4.
Cell Death Differ ; 27(7): 2234-2247, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31988496

RESUMO

The molecular and genetic basis of tumor recurrence is complex and poorly understood. RIPK3 is a key effector in programmed necrotic cell death and, therefore, its expression is frequently suppressed in primary tumors. In a transcriptome profiling between primary and recurrent breast tumor cells from a murine model of breast cancer recurrence, we found that RIPK3, while absent in primary tumor cells, is dramatically reexpressed in recurrent breast tumor cells by an epigenetic mechanism. Unexpectedly, we found that RIPK3 knockdown in recurrent tumor cells reduced clonogenic growth, causing cytokinesis failure, p53 stabilization, and repressed the activities of YAP/TAZ. These data uncover a surprising role of the pro-necroptotic RIPK3 kinase in enabling productive cell cycle during tumor recurrence. Remarkably, high RIPK3 expression also rendered recurrent tumor cells exquisitely dependent on extracellular cystine and undergo necroptosis upon cystine deprivation. The induction of RIPK3 in recurrent tumors unravels an unexpected mechanism that paradoxically confers on tumors both growth advantage and necrotic vulnerability, providing potential strategies to eradicate recurrent tumors.

5.
Cell Biol Int ; 44(2): 381-390, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31508857

RESUMO

RASSF4, a member of the classical RASSF family of scaffold proteins, is associated with alveolar rhabdomyosarcoma, an aggressive pediatric cancer of muscle histogenesis. However, the role of RASSF4 in normal myogenesis is unknown. We demonstrate here that RASSF4 is necessary for early in vitro myogenesis. Using primary human myoblasts, we show that RASSF4 expression is dramatically increased during in vitro myogenic differentiation, and conversely that RASSF4-deficient myoblasts cannot differentiate, potentially because of a lack of upregulation of myogenin. In microscopy studies, we show that RASSF4 protein co-localizes with proteins of the myogenic microtubule-organizing center (MTOC) both before and after myogenic differentiation. RASSF4-deficient cells subject to differentiation conditions demonstrate a lack of shape change, suggesting that RASSF4 plays a role in promoting microtubule reorganization and myoblast elongation. In biochemical studies of myotubes, RASSF4 associates with MST1, suggesting that RASSF4 signals to MST1 in the myogenic differentiation process. Expression of MST1 in myoblasts partially reversed the effect of RASSF4 knockdown on differentiation, suggesting that RASSF4 and MST1 coordinately support myogenic differentiation. These data show that RASSF4 is critical for the early steps of myogenic differentiation.

6.
J Food Drug Anal ; 28(1): 147-158, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31883603

RESUMO

The incidence of neurodegeneration leading to the conditions such as Alzheimer's and Parkinson's diseases are on the increase, they require the approaches that focus on protection prevention rather than treatment. Plants are rich sources of many compounds which possess medicinal properties. We sought to investigate the neuroprotective effects of Uncariahirsuta and its compounds on d-galactose-induced stress in BALB/c mice as well as 6-hydroxydopamine (6-OHDA)-induced stress in mouse nerve growth factor (mNGF)-differentiated PC12 cells. Our results demonstrate that the 95% ethanol extract of U. hirsuta reversed the d-galactose-induced learning and memory dysfunctions and decreased the malodialdehyde levels. Furthermore, the isolated compounds, 5ß-carboxystrictosidine (1) and chlorogenic acid (2), protected mNGF-differentiated PC12 cells against toxicity induced by 6-OHDA by acting as antiapoptotic agents. The 50% inhibitory concentration (IC50) for intracellular reactive oxygen species (ROS) scavenging was found to be 24.5 (for 1) and 19.7 µM (for 2), and both 1 and 2 reduced intracellular calcium levels with respective IC50 values of 46.9 and 27 µM. Interestingly, both compounds inhibited caspase 3 and 9 activities with respective IC50 values of 25.6 and 24.5 µM for 1 and 19.4 and 16.3 µM for 2. Our results identify U. hirsuta and its active compounds as potential neuroprotective agents and deserve further evaluation for drug development for neuroprotection in the future.

7.
Int J Mol Sci ; 20(13)2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31247918

RESUMO

Bone metabolism is a homeostatic process, imbalance in which leads to the onset of diseases such as osteoporosis and osteopenia. Although several drugs are currently available to treat such conditions, they are associated with severe side effects and do not enhance bone formation. Thus, identifying alternative treatment strategies that focus on enhancing bone formation is essential. Herein, we explored the osteogenic potential of Turpinia formosana Nakai using human osteoblast (HOb) cells. The plant extract was subjected to various chromatographic techniques to obtain six compounds, including one new compound: 3,3'-di-O-methylellagic acid-4-O-α-l-arabinofuranoside (1). Compounds 3,3'-di-O-methylellagic acid-4-O-α-l-arabinofuranoside (1), gentisic acid 5-O-ß-d-(6'-O-galloyl) glucopyranoside (2), strictinin (3), and (-)-epicatechin-3-O-ß-d-allopyranoside (6) displayed no significant cytotoxicity toward HOb cells, and thus their effects on various osteogenic markers were analyzed. Results showed that 1-3 and 6 significantly increased alkaline phosphatase (ALP) activity up to 120.0, 121.3, 116.4, and 125.1%, respectively. Furthermore, 1, 2, and 6 also markedly enhanced the mineralization process with respective values of up to 136.4, 118.9, and 134.6%. In addition, the new compound, 1, significantly increased expression levels of estrogen receptor-α (133.4%) and osteogenesis-related genes of Runt-related transcription factor 2 (Runx2), osteopontin (OPN), bone morphogenetic protein (BMP)-2, bone sialoprotein (BSP), type I collagen (Col-1), and brain-derived neurotropic factor (BDNF) by at least 1.5-fold. Our results demonstrated that compounds isolated from T. formosana possess robust osteogenic potential, with the new compound, 1, also exhibiting the potential to enhance the bone formation process. We suggest that T. formosana and its isolated active compounds deserve further evaluation for development as anti-osteoporotic agents.


Assuntos
Calcificação Fisiológica/efeitos dos fármacos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Traqueófitas/química , Biomarcadores , Expressão Gênica , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Receptores Estrogênicos/genética , Receptores Estrogênicos/metabolismo
8.
Polymers (Basel) ; 11(6)2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151173

RESUMO

The electronic package interconnects electronic signals from one area to another and package delamination is a serious problem in the configuration of materials. This study focused on decreasing the delamination of the low-profile fine pitch ball grid array (LFBGA) and plastic ball grid array (PBGA) packages in terms of polymer thermal issue, metal bonding and bonding mechanisms. PBGA and LFBGA are a very common type of packaging processes in the electronics industry. The present study dealt first with delamination of the LFBGA packaging, through characterization and determination of physical and chemical properties such as surface roughness, surface energy, and contact angle. The relationship between surface roughness and delamination was verified through various roughness bonding experiments. In addition, the surface energy was determined by measuring the contact angle after cleaning the metal surface of Cu, Ni and Cr with Ar + O2 gas, and, this gas plasma treatment was applied to enhance the adhesive properties. The compositions of the surface were analyzed through an X-ray photoelectron spectroscopy (XPS). Also, the delamination issue between the corner of the heat sink cap and the epoxy resin was observed for delamination of the LFBGA packaging. Further, this study analyzed the PBGA packaging process through the finite element analysis simulation software ANSYS. To improve the heat sink cap delamination issue of the PBGA, a new chamfer design of the corner seat was streamlined to decrease the stress value and delamination. Besides, the simulation results demonstrated that the stress value reduced after increasing the shoulder length. The results implicate that the stress value is inversely proportional to the shoulder width and the chamfer radius. This study demonstrated that the optimization in design was able reduce the delamination phenomena in configuration material.

9.
PLoS Genet ; 15(5): e1007895, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31116734

RESUMO

XX and XY fetal gonads are initially bipotential, poised between the ovary and testis fate. Multiple lines of evidence suggest that commitment to testis fate requires the repression of genes associated with ovary fate. It was previously shown that loss of CBX2, the subunit of the Polycomb Repressive Complex 1 (PRC1) that binds H3K27me3 and mediates silencing, leads to ovary development in XY mice and humans. While it had been proposed that CBX2 is an activator of the testis-determining gene Sry, we investigated the alternative possibility that CBX2 has a direct role as a repressor of the antagonistic ovary-promoting pathway. To investigate this possibility, we developed a quantitative genome-wide profile of the repressive histone mark H3K27me3 and its active counterpart H3K4me3 in isolated XY and XX gonadal supporting cells before and after sex determination. We show that testis and ovary sex-determining (SD) genes are bivalent before sex determination, providing insight into how the bipotential state of the gonad is established at the epigenetic level. After sex determination, many SD genes of the alternate pathway remain bivalent, possibly contributing to the ability of these cells to transdifferentiate even in adults. The finding that many genes in the Wnt signaling pathway were targeted for H3K27me3-mediated repression in Sertoli cells led us to test whether deletion of Wnt4 could rescue testis development in Cbx2 mutants. We show that Sry expression and testis development were rescued in XY Cbx2-/-;Wnt4-/- mice. Furthermore, we show that CBX2 directly binds the downstream Wnt signaler Lef1, an ovary-promoting gene that remains bivalent in Sertoli cells. Our results suggest that stabilization of the testis fate requires CBX2-mediated repression of bivalent ovary-determining genes, which would otherwise block testis development.


Assuntos
Epigênese Genética , Ovário/metabolismo , Complexo Repressor Polycomb 1/genética , Processos de Determinação Sexual , Testículo/metabolismo , Via de Sinalização Wnt/genética , Animais , Embrião de Mamíferos , Feminino , Fator 9 de Crescimento de Fibroblastos/genética , Fator 9 de Crescimento de Fibroblastos/metabolismo , Proteína Forkhead Box L2/genética , Proteína Forkhead Box L2/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Histonas/genética , Histonas/metabolismo , Humanos , Fator 1 de Ligação ao Facilitador Linfoide/genética , Fator 1 de Ligação ao Facilitador Linfoide/metabolismo , Masculino , Camundongos , Ovário/citologia , Ovário/crescimento & desenvolvimento , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Complexo Repressor Polycomb 1/deficiência , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Diferenciação Sexual , Testículo/citologia , Testículo/crescimento & desenvolvimento , Proteína Wnt4/genética , Proteína Wnt4/metabolismo
10.
Cancer Res ; 78(19): 5513-5520, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30093562

RESUMO

A hallmark of fusion-positive alveolar rhabdomyosarcoma (aRMS) is the presence of a chromosomal translocation encoding the PAX3-FOXO1 fusion oncogene. Primary cell-based modeling experiments have shown that PAX3-FOXO1 is necessary, but not sufficient for aRMS tumorigenesis, indicating additional molecular alterations are required to initiate and sustain tumor growth. Previously, we showed that PAX3-FOXO1-positive aRMS is promoted by dysregulated Hippo pathway signaling, as demonstrated by increased YAP1 expression and decreased MST activity. We hypothesized that ablating MST/Hippo signaling in a genetically engineered mouse model (GEMM) of aRMS would accelerate tumorigenesis. To this end, MST1/2-floxed (Stk3F/F;Stk4F/F ) mice were crossed with a previously established aRMS GEMM driven by conditional expression of Pax3:Foxo1 from the endogenous Pax3 locus and conditional loss of Cdkn2a in Myf6 (myogenic factor 6)-expressing cells. Compared with Pax3PF/PF;Cdkn2aF/F;Myf6ICN/+ controls, Stk3F/F;Stk4F/F;Pax3PF/PF;Cdkn2aF/F;Myf6ICN/+ animals displayed accelerated tumorigenesis (P < 0.0001) and increased tumor penetrance (88% vs. 27%). GEMM tumors were histologically consistent with aRMS. GEMM tumor-derived cell lines showed increased proliferation and invasion and decreased senescence and myogenic differentiation. These data suggest that loss of MST/Hippo signaling acts with Pax3:Foxo1 expression and Cdkn2a loss to promote tumorigenesis. The rapid onset and increased penetrance of tumorigenesis in this model provide a powerful tool for interrogating aRMS biology and screening novel therapeutics.Significance: A novel mouse model sheds light on the critical role of Hippo/MST downregulation in PAX3-FOXO1-positive rhabdomyosarcoma tumorigenesis. Cancer Res; 78(19); 5513-20. ©2018 AACR.


Assuntos
Proteína Forkhead Box O1/metabolismo , MAP Quinase Quinase Quinases/metabolismo , Fator de Transcrição PAX3/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Rabdomiossarcoma Alveolar/genética , Rabdomiossarcoma Alveolar/metabolismo , Animais , Carcinogênese , Diferenciação Celular , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/genética , Senescência Celular , Cruzamentos Genéticos , Modelos Animais de Doenças , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Engenharia Genética , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Invasividade Neoplásica , Proteínas de Fusão Oncogênica/genética , Oncogenes , Transdução de Sinais
11.
J Photochem Photobiol B ; 175: 244-253, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28917186

RESUMO

Ultraviolet (UV) irradiation leads to skin photoaging because of the upregulation of matrix metalloproteinase (MMP)-1 and downregulation of type I collagen and tissue inhibitor of metalloproteinase (TIMP)-1. Eriobotrya deflexa (Hemsl.) Nakai (Rosaceae) is a flowering plant endemic to Taiwan, and its leaves have been used as an expectorant and in antitussive folk remedy. Our previous studies have demonstrated that an E. deflexa leaf extract functions as a free radical scavenger. The current evaluated the antiphotoaging effect of partitioned fractions and specific compounds from the leaves of E. deflexa by using bioguided isolation, compound identification, and biological activity testing with UVB-irradiated human fibroblasts (WS-1 cells). E. deflexa leaves were extracted with 95% ethanol and then partitioned using a sequential treatment of n-hexane, ethyl acetate, and n-butanol (n-BuOH). The bioactive n-BuOH fraction was used for isolation and purification through chromatography. The compounds were identified by analyzing their physical and spectroscopic properties. We identified eight compounds from this fraction; of these compounds, 3-O-α-l-rhamnopyranosyl-(1‴→6″)-ß-d-galactopyranoside (1), hyperin (2), afzelin (5), and cryptochlorogenic acid methyl ester (7) were isolated from E. deflexa for the first time, and they exhibited MMP-1 inhibition activity. The IC50 values were 96.5, 89.5, 93.4, and 92.8µM for 1, 2, 5, and 7, respectively. These compounds also enhanced the expression of procollagen type I, and TIMP-1 and hyperin (2) were found to be most effective with IC50 values of 56.7 and 70.3µM, respectively. Hyperin (2) could reduce intracellular reactive oxygen species production in UVB-irradiated WS-1 cells, with the corresponding IC50 value being 80.7µM. Liquid chromatography triple-quadrupole mass spectrometry was used for the quantitative and chemical fingerprint analysis of active compounds. Quercetin 3-O-α-l-rhamnopyranosyl-(1‴→6″)-ß-d-galactopyranoside (1), hyperin (2), afzelin (5), and cryptochlorogenic acid methyl ester (7) constituted 24.2±3.9, 5.5±1.0, 3.4±0.3, and 67.1±8.1mg/g of dry weight in the active n-BuOH fraction, respectively. Our results demonstrate that the extract and the isolated active compounds from E. deflexa leaves possess the potential for protection against skin photoaging.


Assuntos
Senescência Celular/efeitos dos fármacos , Eriobotrya/química , Extratos Vegetais/química , Substâncias Protetoras/química , Raios Ultravioleta , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Senescência Celular/efeitos da radiação , Cromatografia Líquida de Alta Pressão , Colágeno Tipo I/análise , Ensaio de Imunoadsorção Enzimática , Eriobotrya/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Humanos , Metaloproteinase 1 da Matriz/análise , Extratos Vegetais/análise , Folhas de Planta/química , Folhas de Planta/metabolismo , Substâncias Protetoras/isolamento & purificação , Substâncias Protetoras/farmacologia , Espectrometria de Massas em Tandem
12.
Development ; 144(9): 1607-1618, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28360133

RESUMO

During early gonadogenesis, proliferating cells in the coelomic epithelium (CE) give rise to most of the somatic cells in both XX and XY gonads. Previous dye-labeling experiments showed that a single CE cell could give rise to additional CE cells and to both supporting and interstitial cell lineages, implying that cells in the CE domain are multipotent progenitors, and suggesting that an asymmetric division is involved in the acquisition of gonadal cell fates. We found that NUMB is asymmetrically localized in CE cells, suggesting that it might be involved. To test this hypothesis, we conditionally deleted Numb on a Numbl mutant background just prior to gonadogenesis. Mutant gonads showed a loss of cell polarity in the surface epithelial layers, large interior cell patches expressing the undifferentiated cell marker LHX9, and a loss of differentiated cells in somatic cell lineages. These results indicate that NUMB is necessary for establishing polarity in CE cells, and that asymmetric divisions resulting from CE polarity are required for commitment to differentiated somatic cell fates. Surprisingly, germ cells, which do not arise from the CE, were also affected in mutants, which may be a direct or indirect effect of loss of Numb.


Assuntos
Linhagem da Célula , Gônadas/embriologia , Gônadas/metabolismo , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Organogênese , Animais , Divisão Celular Assimétrica/efeitos dos fármacos , Contagem de Células , Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem da Célula/efeitos dos fármacos , Polaridade Celular/efeitos dos fármacos , Polaridade Celular/genética , Células Cultivadas , Dipeptídeos/farmacologia , Embrião de Mamíferos/citologia , Embrião de Mamíferos/efeitos dos fármacos , Embrião de Mamíferos/metabolismo , Epitélio/embriologia , Epitélio/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Gônadas/efeitos dos fármacos , Gônadas/patologia , Proteínas com Homeodomínio LIM/metabolismo , Células Intersticiais do Testículo/citologia , Células Intersticiais do Testículo/efeitos dos fármacos , Células Intersticiais do Testículo/metabolismo , Masculino , Proteínas de Membrana/genética , Camundongos , Modelos Biológicos , Mutação/genética , Proteínas do Tecido Nervoso/genética , Organogênese/efeitos dos fármacos , Organogênese/genética , Fenótipo , Receptores Notch/genética , Receptores Notch/metabolismo , Células de Sertoli/citologia , Células de Sertoli/efeitos dos fármacos , Células de Sertoli/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/metabolismo
13.
Int J Mol Sci ; 16(12): 28598-613, 2015 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-26633381

RESUMO

Nontoxic natural products useful in skin care cosmetics are of considerable interest. Tyrosinase is a rate-limiting enzyme for which its inhibitor is useful in developing whitening cosmetics. Pyracantha koidzumii (Hayata) Rehder is an endemic species in Taiwan that exhibits tyrosinase-inhibitory activity. To find new active natural compounds from P. koidzumii, we performed bioguided isolation and studied the related activity in human epidermal melanocytes. In total, 13 compounds were identified from P. koidzumii in the present study, including two new compounds, 3,6-dihydroxy-2,4-dimethoxy-dibenzofuran (9) and 3,4-dihydroxy-5-methoxybiphenyl-2'-O-ß-d-glucopyranoside (13), as well as 11 known compounds. The new compound 13 exhibited maximum potency in inhibiting cellular tyrosinase activity, the protein expression of cellular tyrosinase and tyrosinase-related protein-2, as well as the mRNA expression of Paired box 3 and microphthalmia-associated transcription factor in a concentration-dependent manner. In the enzyme kinetic assay, the new compound 13 acted as an uncompetitive mixed-type inhibitor against the substrate l-3,4-dihydroxyphenylalanine and had a Km value against this substrate of 0.262 mM, as calculated using the Lineweaver-Burk plots. Taken together, our findings show compound 13 exhibits tyrosinase inhibition in human melanocytes and compound 13 may be a potential candidate for use in cosmetics.


Assuntos
Clareadores/química , Clareadores/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Pyracantha/química , Clareadores/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Células Epidérmicas , Epiderme/efeitos dos fármacos , Humanos , Melanócitos/efeitos dos fármacos , Melanócitos/metabolismo , Estrutura Molecular , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/química , Ressonância Magnética Nuclear Biomolecular , Extratos Vegetais/isolamento & purificação , Taiwan
14.
Curr Opin Genet Dev ; 32: 144-52, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25841206

RESUMO

The gonads form bilaterally as bipotential organs that can develop as testes or ovaries. All secondary sex characteristics that we associate with 'maleness' or 'femaleness' depend on whether testes or ovaries form. The fate of the gonads depends on a cell fate decision that occurs in a somatic cell referred to as the 'supporting cell lineage'. Once supporting cell progenitors commit to Sertoli (male) or granulosa (female) fate, they propagate this decision to the other cells within the organ. In this review, we will describe what is known about the bipotential state of somatic and germ cell lineages in the gonad and the transcriptional and antagonistic signaling networks that lead to commitment, propagation, and maintenance of testis or ovary fate.


Assuntos
Linhagem da Célula/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Células Germinativas/fisiologia , Gônadas/embriologia , Mamíferos/embriologia , Modelos Biológicos , Organogênese/fisiologia , Processos de Determinação Sexual/fisiologia , Animais , Feminino , Humanos , Masculino , Fatores de Transcrição/metabolismo
15.
ACS Chem Neurosci ; 6(5): 716-24, 2015 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-25692332

RESUMO

Lovastatin, a secondary metabolite isolated from Monascus-fermented red rice mold, has neuroprotective activity and permeates the blood-brain barrier. The aim of this study was to enhance the activity of lovastatin for potential use as a treatment for neuronal degeneration in Parkinson's disease. Six lovastatin-derived compounds were semisynthesized and screened for neurocytoprotective activity against 6-hydroxydopamine (6-OHDA)-induced toxicity in human neuroblastoma PC12 cells. Four compounds, designated as 3a, 3d, 3e, and 3f, significantly enhanced cell viability. In particular, compound 3f showed excellent neurocytoprotective activity (97.0 ± 2.7%). Annexin V-FITC and propidium iodide double staining and 4',6-diamidino-2-phenylindole staining indicated that compound 3f reduced 6-OHDA-induced apoptosis in PC12 cells. Compound 3f also reduced caspase-3, -8, and -9 activities, and intracellular calcium concentrations elevated by 6-OHDA in a concentration-dependent manner, without inhibiting reactive oxygen species generation. JC-1 staining indicated that compound 3f also stabilized mitochondrial membrane potential. Thus, compound 3f may be used as a neurocytoprotective agent. Future studies should investigate its potential application as a treatment for Parkinson's disease.


Assuntos
Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Lovastatina/análogos & derivados , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Animais , Diferenciação Celular , Modelos Biológicos , Monascus , Fator de Crescimento Neural , Oryza , Oxidopamina , Células PC12 , Transtornos Parkinsonianos , Ratos
16.
Biochem Biophys Res Commun ; 428(3): 422-6, 2012 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-23111326

RESUMO

Deleted in Azoospermia Associated Protein 1 (DAZAP1) is a ubiquitous hnRNP protein required for normal development and spermatogenesis. It resides predominantly in the nucleus and moves between the nucleus and the cytoplasm via a ZNS shuttling signal at its C-terminus. DAZAP1 accumulates in the cytoplasm when RNA polymerase II activity is inhibited by actinomycin D. Here we report the mapping of a 42-amino acid segment (N42) at the N-terminus of DAZAP1 that is both necessary and sufficient for its transcription-dependent nuclear localization. In addition, using a yeast two-hybrid system, we have identified SLIRP as a N42-binding protein which may regulate DAZAP1 subcellular localization.


Assuntos
Núcleo Celular/metabolismo , Sinais de Localização Nuclear/metabolismo , Proteínas de Ligação a RNA/metabolismo , Transcrição Genética , Transporte Ativo do Núcleo Celular , Sequência de Aminoácidos , Humanos , Dados de Sequência Molecular , Sinais de Localização Nuclear/genética , Mapas de Interação de Proteínas , Proteínas de Ligação a RNA/genética
17.
Dev Biol ; 370(1): 24-32, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22705479

RESUMO

The bipotential gonad expresses genes associated with both the male and female pathways. Adoption of the male testicular fate is associated with the repression of many female genes including Wnt4. However, the importance of repression of Wnt4 to the establishment of male development was not previously determined. Deletion of either Fgf9 or Fgfr2 in an XY gonad resulted in up-regulation of Wnt4 and male-to-female sex reversal. We investigated whether the deletion if Wnt4 could rescue sex reversal in Fgf9 and Fgfr2 mutants. XY Fgf9/Wnt4 and Fgfr2/Wnt4 double mutants developed testes with male somatic and germ cells present, suggesting that the primary role of Fgf signaling is the repression of female-promoting genes. Thus, the decision to adopt the male fate is based not only on whether male genes, such as Sox9, are expressed, but also on the active repression of female genes, such as Wnt4. Because loss of Wnt4 results in the up-regulation of Fgf9, we also tested the possibility that derepression of Fgf9 was responsible for the aspects of male development observed in XX Wnt4 mutants. However, we found that the relationship between these two signaling factors is not symmetric: loss of Fgf9 in XX Wnt4(-/-) gonads does not rescue their partial female-to-male sex-reversal.


Assuntos
Fator 9 de Crescimento de Fibroblastos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/genética , Processos de Determinação Sexual/fisiologia , Transdução de Sinais/genética , Testículo/embriologia , Proteína Wnt4/metabolismo , Animais , Primers do DNA/genética , Feminino , Fator 2 de Crescimento de Fibroblastos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Masculino , Camundongos , Microscopia de Fluorescência , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/fisiologia
18.
Curr Genomics ; 13(8): 633-45, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23730203

RESUMO

Toll-like receptors (TLRs), a large group of proteins which recognize various pathogen-associated molecular patterns, are critical for the normal function of the innate immune system. Following their discovery many single nucleotide polymorphisms within TLRs and components of their signaling machinery have been discovered and subsequently implicated in a wide range of human diseases including atherosclerosis, sepsis, asthma, and immunodeficiency. This review discusses the effect of genetic variation on TLR function and how they may precipitate disease.

19.
Mol Cell Biol ; 28(11): 3652-62, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18362163

RESUMO

Spindle integrity is critical for efficient mitotic progression and accurate chromosome segregation. Deregulation of spindles often leads to structural and functional aberrations, ultimately promoting segregation errors and aneuploidy, a hallmark of most human cancers. Here we report the characterization of a previously identified human sarcoma antigen (gene located at 19p13.11), Hice1, an evolutionarily nonconserved 46-kDa coiled-coil protein. Hice1 shows distinct cytoplasmic localization and associates with interphase centrosomes and mitotic spindles, preferentially at the spindle pole vicinity. Depletion of Hice1 by RNA interference resulted in abnormal and unstable spindle configurations, mitotic delay at prometaphase and metaphase, and elevated aneuploidy. Conversely, loss of Hice1 had minimal effects on interphase centrosome duplication. We also found that both full-length Hice1 and Hice1-N1, which is composed of 149 amino acids of the N-terminal region, but not the mutant lacking the N-terminal region, exhibited activities of microtubule bundling and stabilization at a near-physiological concentration. Consistently, overexpression of Hice1 rendered microtubule bundles in cells resistant to nocodazole- or cold-treatment-induced depolymerization. These results demonstrate that Hice1 is a novel microtubule-associated protein important for maintaining spindle integrity and chromosomal stability, in part by virtue of its ability to bind, bundle, and stabilize microtubules.


Assuntos
Instabilidade Cromossômica/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Mitose/genética , Fuso Acromático/metabolismo , Sequência de Aminoácidos , Linhagem Celular , Humanos , Proteínas Associadas aos Microtúbulos/análise , Proteínas Associadas aos Microtúbulos/genética , Dados de Sequência Molecular , Fuso Acromático/ultraestrutura
20.
RNA ; 12(8): 1486-93, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16772659

RESUMO

Deleted in Azoospermia Associated Protein 1 (DAZAP1) is a ubiquitous RNA-binding protein highly expressed in the human and the mouse testes. It shows a dynamic subcellular localization during spermatogenesis, present predominantly in the nuclei of late-stage spermatocytes and round spermatids and translocated to the cytoplasm during spermatid elongation. To test the hypothesis that DAZAP1 shuttles between the nucleus and the cytoplasm, we studied the nuclear transport of DAZAP1 in somatic cells using immunostaining, heterokaryon formation, and mutagenesis. DAZAP1 is detected exclusively in the nucleus and has the ability to shuttle between the nucleus and the cytoplasm using a highly conserved 25 amino acid segment, designated ZNS, at its C terminus. ZNS shares no sequence homology with other known nuclear localization or export signals. Attachment of ZNS to a red fluorescent protein DsRed2 confers the nucleocytoplasmic shuttling ability to that protein. The nuclear localization of DAZAP1 depends on active transcription. In the presence of an RNA polymerase II inhibitor, DAZAP1 is retained in the cytoplasm. DAZAP1 colocalizes with hnRNP A1 and hnRNP C1 in the nucleus and is a component of the heterogeneous nuclear ribonucleoprotein particles. Our results suggest that DAZAP1 plays a key role in mRNA transport during spermatogenesis.


Assuntos
Núcleo Celular/metabolismo , Citoplasma/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Testículo/química , Células 3T3 , Transporte Ativo do Núcleo Celular/fisiologia , Sequência de Aminoácidos , Animais , Células COS , Linhagem Celular , Chlorocebus aethiops , Sequência Conservada , Dactinomicina/farmacologia , Células HeLa , Ribonucleoproteína Nuclear Heterogênea A1 , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/isolamento & purificação , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas Grupo C/isolamento & purificação , Ribonucleoproteínas Nucleares Heterogêneas Grupo C/metabolismo , Humanos , Masculino , Camundongos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Mutação , Sinais de Localização Nuclear , Proteínas de Ligação a RNA/genética , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Transcrição Genética/efeitos dos fármacos
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