1,721,095 research outputs found
Unprecedented Behavior of (9 R)-9-Hydroxystearic Acid-Loaded Keratin Nanoparticles on Cancer Cell Cycle
Full text linkHistone deacetylases, HDACs, have been demonstrated to play a critical role in epigenetic signaling and were found to be overexpressed in several type of cancers; therefore, they represent valuable targets for anticancer therapy. 9-Hydroxystearic acid has been shown to bind the catalytic site of HDAC1, inducing G0/G1 phase cell cycle arrest and activation of the p21 WAF1 gene, thus promoting cell growth inhibition and differentiation in many cancer cells. Despite the (R) enantiomer of 9-hydroxystearic acid (9R) displaying a promising in vitro growth-inhibitory effect on the HT29 cell line, its scarce water solubility and micromolar activity require novel solutions for improving its efficacy and bioavailability. In this work, we describe the synthesis and in vitro biological profiling of 9R keratin nanoparticles (9R@ker) obtained through an in-water drug-induced aggregation process. The anticancer activity of 9R@ker was investigated in the HT29 cell line; the results indicate an increased fluidity of cell membrane and a higher intracellular ROS formation, resulting in an unexpected S phase cell cycle arrest (25% increase as compared to the control) induced by 9R@ker with respect to free 9R and an induction of cell death
Chitosan nanoparticles for lipophilic anticancer drug delivery: Development, characterization and in vitro studies on HT29 cancer cells
No full textThe aim of this study was to develop chitosan-based nanoparticles that could encapsulate lipophilic molecules and deliver them to cancer cells. Nanoparticles were prepared with different molar ratios of chitosan, hyaluronic acid and sulphobutyl-ether-β-cyclodextrin and with or without curcumin. The nanosystems were characterized in terms of their size, zeta potential, morphology, encapsulation efficiency and stability in different media. Intestinal epithelial and colorectal cancer cells were treated with unloaded nanoparticles in order to study their effect on cellular membrane organization and ROS production. Finally, in vitro assays on both cellular lines were performed in order to evaluate the ability of nanoparticles to promote curcumin internalization and to study their effect on cell proliferation and cell cycle. Results show that nanoparticles were positively charged and their size increased with the increasing amounts of the anionic excipient. Nanoparticles showed good encapsulation efficiency and stability in water. Unloaded nanoparticles led to a change in lipid organization in the cellular membrane of both cell lines, without inducing ROS generation. Confocal microscopy, cell proliferation and cell cycle studies allowed the selection of the best formulation to limit curcumin cytotoxicity in normal intestinal epithelial cells and to reduce cancer cell proliferation. The latter was the result of the increase of expression for genes involved in apoptosis
Synthesis and Antiproliferative Activity against Cancer Cells of Indole-Aryl-Amide Derivatives
Full text linkIndoles constitute a large family of heterocyclic compounds widely occurring in nature which are present in a number of bioactive natural and synthetic compounds, including anticancer agents or atypical opioid agonists. As a result, exponential increases in the development of novel methods for the synthesis of indole-containing compounds have been reported in the literature. A series of indole-aryl amide derivatives 1–7 containing tryptamine or an indolylacetic acid nucleus were designed, synthesized, and evaluated as opioid ligands. These new indole derivatives showed negligible to very low affinity for μ- and δ-opioid receptor (OR). On the other hand, compounds 2, 5 and 7 showed Ki values in the low μM range for κ-OR. Since indoles are well known for their anticancer potential, their effect against a panel of tumor cell lines was tested. The target compounds were evaluated for their in vitro cytotoxicity in HT29, HeLa, IGROV-1, MCF7, PC-3, and Jurkat J6 cells. Some of the synthesized compounds showed good activity against the selected tumor cell lines, with the exception of IGROV1. In particular, compound 5 showed a noteworthy selectivity towards HT29 cells, a malignant colonic cell line, without affecting healthy human intestinal cells. Further studies revealed that 5 caused the cell cycle arrest in the G1 phase and promoted apoptosis in HT29 cells
Synthesis, cytotoxicity and anti-cancer activity of new alkynyl-gold(I) complexes
Full text linkAlkynyl(triphenylphosphine)gold(I) complexes carrying variously substituted propargylic amines have been synthesized and fully characterized in solution and solid state. High levels of toxicity (i.e. micromolar range) were recognized for a series of cancer cell lines with particular emphasis on HT29, IGROV1, HL60 and I407. In particular the lead compound 3ab was identified as the most active compound in all cell lines (IC50: 1.7–7.9 μM)
A peptidic hydrogel that may behave as a “Trojan Horse”
No full textA physical hydrogel prepared with the low-molecular-weight hydrogelator (LMWHG) CH2(C3H6CO-L-Phe-D-Oxd-OH)2 and water/ethanol mixture was applied as a potential “Trojan Horse” carrier into cells. By SEM and XRD analysis we could demonstrate that a fibrous structure is present in the xerogel, making a complex network. The gelator is derived from α-amino acids (Thr, Phe) and a fatty acid (azelaic acid) and is biocompatible: it was dosed to IGROV-1 cells, which internalized it, without significantly affecting the cell proliferation. To check the internalization process by confocal microscopy, fluorescent hydrogels were prepared, introducing the fluorescent dansyl moiety into the mixture
Purification of active recombinant human histone deacetylase 1 (HDAC1) overexpressed in Escherichia coli
No full textObjectiveWe attempted to overexpress Human Histone Deacetylase 1 (HDAC1) in Escherichia coli.ResultsA synthetic gene coding for HDAC1, and optimised for E. coli codon usage, was cloned into pBADHisB, generating pBAD-rHDAC1. This construct was used to transform E. coli TOP10, and the target protein was overexpressed and partially purified. According to its elution volume from a Superdex 200 column, the partially purified rHDAC1 was obtained in aggregated form, i.e., as an octamer. The dissociation of octameric HDAC1 was tested using several agents, among which sodium dodecyl sulfate was competent in partially dissociating rHDAC1 aggregates. When the enzyme activity was tested in vitro using H-3-acetyl-labelled histones both protein samples, aggregated and dissociated, were active. Hence, our results suggest that E. coli represents an alternative system for the production of the recombinant HDAC1.ConclusionsWe described a procedure for the overexpression in E. coli of recombinant HDAC1, the purification of which in active form can be successfully performed, although yielding an octameric aggregate
ENDOGENOUS LIPID PEROXIDATION PRODUCT 9-HSA REGULATES PROGENITOR FATE IN THE VERTEBRATE RETINA
No full textEffects of sugars and lactic acid isomers on Chlamydia trachomatis infectivity, an in vitro study
Full text linkThe thesis investigates two different in vitro aspects of Chlamydia trachomatis (CT). The thesis analyzes the effect of different sugars on CT infectivity. which is investigated on HeLa cells after 2 hour-incubation of elementary bodies (EBs) with glucose, sucrose or mannitol. Sugars effect on EB membrane fluidity is investigated by fluorescence anisotropy measurement, whereas changes in lipopolysaccharide exposure are examined by cytofluorimetric analysis. By Western blot experiments, the phosphorylation state of Focal Adhesion Kinase in cells infected with EBs pre-incubated with sugars it’s explored. Sugar significantly increase infectivity, acting on the EB structure. Sugars induce an increase of EB membrane fluidity, leading to changes in LPS exposure. After incubation with sucrose and mannitol, EBs lead to higher FAK phosphorylation, enhancing activation of anti-apoptotic and proliferative signals in the host.
Secondly, the thesis explores the protective effect of different Lactobacilli against CT infection: Lactobacillus crispatus and Lactobacillus reuteri. CT infectivity is evaluated after host cells were treated for 1 hour with diluted supernatant cell-free fraction or with the bacterial cells. Assessed that L.crispatus is more protective than L.reuteri, lactic acid production is evaluated by HPLC. Subsequently Lactate dehydrogenases activity is evaluated by resazurin assay and by LC-MS. Then, D-lactate dehydrogenase specific activity has been investigated by measuring NADH formation. Afterwards, addition of D or L-lactic acid to L.reuteri supernatant has been performed and their effect in promoting protection in the host cells assessed. Then a metabolic analysis has been carried out by real-time measurement of mitochondrial respiration after treatment. Finally, histone acetylation and lactylation, and gene and protein expression of relevant targets, have been investigated. It is shown that the D isomer is more efficient in conferring protection, causing a shift in the host cell metabolic profile and a pattern of histone modifications that changes the expression of important targets
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