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131.
132.
Pectin induces apoptosis in human prostate cancer cells: correlation of apoptotic function with pectin structure 总被引:3,自引:0,他引:3
Jackson CL Dreaden TM Theobald LK Tran NM Beal TL Eid M Gao MY Shirley RB Stoffel MT Kumar MV Mohnen D 《Glycobiology》2007,17(8):805-819
Treatment options for androgen-independent prostate cancer cells are limited. Therefore, it is critical to identify agents that induce death of both androgen-responsive and androgen-insensitive cells. Here we demonstrate that a product of plant cell walls, pectin, is capable of inducing apoptosis in androgen-responsive (LNCaP) and androgen-independent (LNCaP C4-2) human prostate cancer cells. Commercially available fractionated pectin powder (FPP) induced apoptosis (approximately 40-fold above non-treated cells) in both cell lines as determined by the Apoptosense assay and activation of caspase-3 and its substrate, poly(ADP-ribose) polymerase. Conversely, citrus pectin (CP) and the pH-modified CP, PectaSol, had little or no apoptotic activity. Glycosyl residue composition and linkage analyses revealed no significant differences among the pectins. Mild base treatment to remove ester linkages destroyed FPP's apoptotic activity and yielded homogalacturonan (HG) oligosaccharides. The treatment of FPP with pectinmethylesterase to remove galacturonosyl carboxymethylesters and/or with endopolygalacturonase to cleave nonmethylesterified HG caused no major reduction in apoptotic activity, implicating the requirement for a base-sensitive linkage other than the carboxymethylester. Heat treatment of CP (HTCP) led to the induction of significant levels of apoptosis comparable to FPP, suggesting a means for generating apoptotic pectic structures. These results indicate that specific structural elements within pectin are responsible for the apoptotic activity, and that this structure can be generated, or enriched for, by heat treatment of CP. These findings provide the foundation for mechanistic studies of pectin apoptotic activity and a basis for the development of pectin-based pharmaceuticals, nutraceuticals, or recommended diet changes aimed at combating prostate cancer occurrence and progression. 相似文献
133.
Wolfrum C Shi S Jayaprakash KN Jayaraman M Wang G Pandey RK Rajeev KG Nakayama T Charrise K Ndungo EM Zimmermann T Koteliansky V Manoharan M Stoffel M 《Nature biotechnology》2007,25(10):1149-1157
Cholesterol-conjugated siRNAs can silence gene expression in vivo. Here we synthesize a variety of lipophilic siRNAs and use them to elucidate the requirements for siRNA delivery in vivo. We show that conjugation to bile acids and long-chain fatty acids, in addition to cholesterol, mediates siRNA uptake into cells and gene silencing in vivo. Efficient and selective uptake of these siRNA conjugates depends on interactions with lipoprotein particles, lipoprotein receptors and transmembrane proteins. High-density lipoprotein (HDL) directs siRNA delivery into liver, gut, kidney and steroidogenic organs, whereas low-density lipoprotein (LDL) targets siRNA primarily to the liver. LDL-receptor expression is essential for siRNA delivery by LDL particles, and SR-BI receptor expression is required for uptake of HDL-bound siRNAs. Cellular uptake also requires the mammalian homolog of the Caenorhabditis elegans transmembrane protein Sid1. Our results demonstrate that conjugation to lipophilic molecules enables effective siRNA uptake through a common mechanism that can be exploited to optimize therapeutic siRNA delivery. 相似文献
134.
Thakur Devaang Taliaferro Olivia Atkinson Madeleine Stoffel Ryan Guleria Rakeshwar S. Gupta Sudhiranjan 《Molecular biology reports》2022,49(5):3481-3490
Molecular Biology Reports - Pulmonary fibrosis is a debilitating condition with limited therapeutic avenues. The pathogenicity of pulmonary fibrosis constitutes involvement of cellular... 相似文献
135.
Dias Ricardo M. Lima Sergio M. Q. Mendes Liana F. Almeida Daniel F. Paiva Paulo C. Britto Marcelo R. 《Hydrobiologia》2019,829(1):133-142
Hydrobiologia - Cladocerans feed on a variety of phytoplankton food sources, which are variable across space and time. Different phytoplankton groups represent different nutritional quality to... 相似文献
136.
Tainah Silva Galdino Rubem Figueiredo Sadok Menna-Barreto Constança Britto Franklyn Samudio Adeilton Brandão Dário Eluan Kalume 《Analytical biochemistry》2014
We have developed a cell disruption method to produce a protein extract using Trypanosoma cruzi cells based on a straightforward hypoosmotic lysis protocol. The procedure consists of three steps: incubation of the cells in a hypoosmotic lysis buffer, sonication in a water bath, and centrifugation. The final protein extract was designated TcS12. The stages of cell disruption at different incubation times were monitored by differential interference contrast microscopy. After 30 min of incubation in lysis buffer at 4 °C, the T. cruzi epimastigote forms changed from slender to round-shaped parasites. Nevertheless, cell disruption took place following sonication of the sample for 30 min. The efficiency of the methodology was also validated by flow cytometry, which resulted in 72% of propidium iodide (PI)-labeled cells. To estimate the protein extraction yield and the differential protein expression, the proteomics profile of four T. cruzi strains (CL-Brener, Dm28c, Y, and 4167) were analyzed by liquid chromatography tandem mass spectrometry (LCMS/MS) on a SYNAPT HDMS system using the label-free MSE approach. ProteinLynx Global Server (version 2.5) with ExpressionE analysis identified a total of 1153 proteins and revealed 428 differentially expressed proteins among the strains. Gene ontology analysis showed that not only cytosolic proteins but also nuclear and organellar ones were present in the extract. 相似文献
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138.
The relationships between foliage permanence and flowering throughout the year were analyzed in 92 woody species of Cerrado vegetation categorized as either deciduous (DE), semideciduous (SD) or evergreen (EV). Flowering of DE, SD and EV species was investigated via three variables, measured over the course of the year: flowering duration (FLD), calculated as the number of months in flower in each species; flowering distribution (FDI), calculated as the number of species in flower per month; and flowering peak (FPE), defined as the four consecutive months yielding the highest number of species in flower. The months with the highest numbers of species in flower were October (52 species), September (50) and August (49). These months correspond to the period of transition from the dry season to the wet season. In the majority of species studied, seasonal climatic factors were strong enough to induce fruit formation in the dry season and seed dispersal in the following wet season, when sufficient water was available to support germination and plantlet growth. However, significant differences in FLD, FDI and FPE were found among the leaf phenological groups. High FLD in EV species is likely favored by the continuous input of resources from the year-round foliage. In contrast, DE species employ reserves of carbon, water and nutrients to form new leaves and flowers on a crown free of foliage at the end of the dry season. In DE species, their low FLD may reduce the impact of flowering on reserve consumption. SD species showed an intermediate level of foliage persistence, resulting in intermediate FLD values. In addition, SD species exhibited a different pattern of flowering distribution from those of DE and EV species. Many SD species have two flowering periods per year. The first period occurs when the crowns are full of leaves, in the middle of the dry season in June, similar to EV species. The second occurs when only half of the original foliage area is present, near the peak of the dry season in September, similar to DE species. Therefore, despite a strong influence of seasonal climatic conditions on the flowering behavior of DE, SD and EV woody species of Cerrado vegetation, these leaf phenological groups differ significantly in FLD, FDI and FPE. 相似文献
139.
Barbara Waber-Wenger Franck Forterre Kathrin Kuehni-Boghenbor Renzo Danuser Jens Volker Stein Michael Hubert Stoffel 《Histochemistry and cell biology》2014,142(4):433-447
Although intervertebral disc herniation is a well-known disease in dogs, pain management for this condition has remained a challenge. The goal of the present study is to address the lack of information regarding the innervation of anatomical structures within the canine vertebral canal. Immunolabeling was performed with antibodies against protein gene product 9.5, Tuj-1 (neuron-specific class III β-tubulin), calcitonin gene-related peptide, and neuropeptide Y in combination with the lectin from Lycopersicon esculentum as a marker for blood vessels. Staining was indicative of both sensory and sympathetic fibers. Innervation density was the highest in lateral areas, intermediate in dorsal areas, and the lowest in ventral areas. In the dorsal longitudinal ligament (DLL), the highest innervation density was observed in the lateral regions. Innervation was lower at mid-vertebral levels than at intervertebral levels. The presence of sensory and sympathetic fibers in the canine dura and DLL suggests that pain may originate from both these structures. Due to these regional differences in sensory innervation patterns, trauma to intervertebral DLL and lateral dura is expected to be particularly painful. The results ought to provide a better basis for the assessment of medicinal and surgical procedures. 相似文献
140.
Marizélia Rodrigues Costa Ribeiro Maria Teresa Seabra Soares de Britto e. Alves Rosangela Fernandes Lucena Batista Cecília Cláudia Costa Ribeiro Lilia Blima Schraiber Marco Ant?nio Barbieri Heloisa Bettiol Ant?nio Augusto Moura da Silva 《PloS one》2014,9(12)