Human Glioblastoma-astrocytoma Research Articles

ZIKV infection differentially affects the transcriptional profiles in HTR8 and U251 cells

The mechanism by which Zika virus (ZIKV) causes severe birth defects in pregnant women remains unclear. Cell tropisms in placenta and brain play a crucial role in ZIKV pathogenesis, leading to congenital Zika syndrome (CZS). To identify the host factors involved in ZIKV infection, we compared the transcriptional profiles of ZIKV-infected human first-trimester placental trophoblast cells HTR8/SVneo and a human glioblastoma astrocytoma cell line U251. Our results demonstrated that ZIKV exhibited lower rates of mRNA replication and protein expression in HTR8 than in U251 cells, while showing a higher release of infectious viral particles. However, a greater number of differentially expressed genes (DEGs) were found in ZIKV-infected U251 cells than in ZIKV-infected HTR8 cells. Several of these DEGs were enriched in distinct biological processes related to the characteristics of each cell type that may contribute to foetal damage. Both cell types exhibited activation of common interferons, inflammatory cytokines, and chemokine production upon ZIKV infection. Moreover, the neutralization of tumour necrosis factor-alpha (TNF-α) promoted ZIKV infection in both trophoblasts and glioblastoma astrocytoma cells. Overall, we identified multiple DEGs associated with ZIKV pathogenesis.

Investigation of Bioactivity of Estragole Isolated from Basil Plant on Brain Cancer Cell Lines Using Nuclear Method.

In recent years, there has been a significant increase in studies investigating the potential use of plant-origin products in the treatment and diagnosis of different types of cancer. In this study, Estragole (EST) was isolated from basil leaves via ethanolic extraction using an 80% ethanol concentration. The isolation process was performed using the High Performance Liquid Chromatography (HPLC) method. The EST isolated from the basil plant was radiolabeled with 131I using the iodogen method. Quality control studies of the radiolabeled EST (131IEST) were carried out by using Thin Layer Radio Chromatography (TLRC). Next, in vitro cell, culture studies were done to investigate the bio-affinity of plant-originated EST labeled with 131I on human medulloblastoma (DAOY) and human glioblastoma-astrocytoma (U-87 MG) cell lines. Finally, the cytotoxicity of EST was determined, and cell uptake of 131I-EST was investigated on cancer cell lines by incorporation studies. As a result of these studies, it has been shown that 131I-EST has a significant uptake on the brain cells. This result is very satisfying, and it has encouraged us to do in vivo studies for the molecule in the future.

Highly selective zinc(II) triggered “Turn-ON” [5]helicene-based fluorescence sensor: Its application in liver and brain cells imaging

A novel fluorescence sensor (MT) was successfully designed and synthesized based on a [5]helicene derivative bearing tris(2-pyridylmethyl)amine as a selective zinc ion (Zn2+) recognition. MT allowed a favorable Zn2+-triggered “turn-on” hypsochromic fluorescence response through the intramolecular charge transfer process. The limit of detection of MT was 29 nM (1.91 ppb), which was considerably below the limit recommended by the World Health Organisation for the amount of Zn2+ in drinking water (76 μM). MT showed an excellent selectivity toward Zn2+ in HEPES buffer: MeOH (5 mM, pH 7.2, 3:2) over other competitive metal ions through a fluorogenic color change from orange to blue, which was easily observed with the naked-eye. The good fluorogenic sensing of the Zn2+ probe helped to determine a small amount of Zn2+ in practical utilization such as a Zn2+-marking agent for intracellular applications in human hepatoma (HepG2) and glioblastoma astrocytoma (U251) cells.

Synthesis and Functionalisation of Superparamagnetic Nano-Rods towards the Treatment of Glioblastoma Brain Tumours.

The complete removal of glioblastoma brain tumours is impossible to achieve by surgery alone due to the complex finger-like tentacle structure of the tumour cells and their migration away from the bulk of the tumour at the time of surgery; furthermore, despite aggressive chemotherapy and radiotherapy treatments following surgery, tumour cells continue to grow, leading to the death of patients within 15 months after diagnosis. The naturally occurring carnosine dipeptide has previously demonstrated activity against in vitro cultured glioblastoma cells; however, at natural physiological concentrations, its activity is too low to have a significant effect. Towards realising the full oncological potential of carnosine, the dipeptide was embedded within an externally triggered carrier, comprising a novel nano rod-shaped superparamagnetic iron oxide nanoparticle (ca. 86 × 19 × 11 nm) capped with a branched polyethyleneimine, which released the therapeutic agent in the presence of an external magnetic field. The new nano-carrier was characterized using electron microscopy, dynamic light scattering, elemental analysis, and magnetic resonance imaging techniques. In addition to cytotoxicity studies, the carnosine carrier’s effectiveness as a treatment for glioblastoma was screened in vitro using the U87 human glioblastoma astrocytoma cell line. The labile carnosine (100 mM) suppresses both the U87 cells’ proliferation and mobility over 48 h, resulting in significant reduction in migration and potential metastasis. Carnosine was found to be fully released from the carrier using only mild hyperthermia conditions (40 °C), facilitating an achievable clinical application of the slow, sustained-release treatment of glioblastoma brain tumours that demonstrates potential to inhibit post-surgery metastasis with the added benefit of non-invasive monitoring via MRI.

Nanofluidics for Simultaneous Size and Charge Profiling of Extracellular Vesicles.

Extracellular vesicles (EVs) are cell-derived membrane structures that circulate in body fluids and show considerable potential for noninvasive diagnosis. EVs possess surface chemistries and encapsulated molecular cargo that reflect the physiological state of cells from which they originate, including the presence of disease. In order to fully harness the diagnostic potential of EVs, there is a critical need for technologies that can profile large EV populations without sacrificing single EV level detail by averaging over multiple EVs. Here we use a nanofluidic device with tunable confinement to trap EVs in a free-energy landscape that modulates vesicle dynamics in a manner dependent on EV size and charge. As proof-of-principle, we perform size and charge profiling of a population of EVs extracted from human glioblastoma astrocytoma (U373) and normal human astrocytoma (NHA) cell lines.

Rutin-Loaded Solid Lipid Nanoparticles: Characterization and In Vitro Evaluation.

This study was aimed at preparing and characterizing solid lipid nanoparticles loading rutin (RT-SLNs) for the treatment of oxidative stress-induced diseases. Phospholipon 80H® as a solid lipid and Polysorbate 80 as surfactant were used for the SLNs preparation, using the solvent emulsification/diffusion method. We obtained spherical RT-SLNs with low sizes, ranging from 40 to 60 nm (hydrodynamic radius) for the SLNs prepared starting from 2% and 5% (w/w) theoretical amount. All prepared formulations showed negative zeta-potential values. RT was efficiently encapsulated within SLNs, obtaining high encapsulation efficiency and drug content percentages, particularly for SLNs prepared with a 5% theoretical amount of RT. In vitro release profiles and analysis of the obtained data applying different kinetic models revealed Fickian diffusion as the main mechanism of RT release from the SLNs. The morphology of RT-SLNs was characterized by scanning electron microscopy (SEM), whereas the interactions between RT and the lipid matrix were investigated by Raman spectroscopy, evidencing spectral modifications of characteristic bands of RT due to the establishment of new interactions. Finally, antioxidant activity assay on human glioblastoma astrocytoma (U373) culture cells showed a dose-dependent activity for RT-SLNs, particularly at the highest assayed dose (50 μM), whereas the free drug showed the lesser activity.

Synthesis of (Z)-3-((5-(benzylthio)-4H-1,2,4-triazol-3-yl)imino)-5-haloindolin-2-one derivatives: combined spectroscopic and computational investigations on the level and activity of matrix metalloproteinases 2 and 9 in cancer cell lines

Angiogenesis is an essential factor for cancer progression. Although more attention is paid in angiogenesis on its role in cancer biology, many other non-neoplastic diseases are also angiogenic-dependent. Recently, there is motivation to control cancer via inhibition of angiogenesis. Isatin-based scaffolds have been extensively used as anticancer agents in the recent years. Although some biological properties of isatin-based scaffolds are determined, their effects on angiogenesis are rare. So, we investigated the antiangiogenic effects of isatin-1,2,4-triazole conjugates. (Z)-3-((5-(benzylthio)-4H-1,2,4-triazol-3-yl)imino)-5-haloindolin-2-one macromolecules 1a–1l were synthesized and characterized, and the buffered solutions were used for evaluation of their cytotoxicity (cell viability) by MTT assay in vitro against U87MG (human glioblastoma astrocytoma) and A2780 (human ovarian carcinoma) cancer cell lines. Also, the effects of the compounds 1a–1l on supernatants activities and levels of matrix metalloproteinases (MMP-2 and MMP-9) were assayed using enzyme-linked immunosorbent assay (ELISA) and gelatin zymography. The compounds 1j–1l have the greatest cytotoxicity against studied cell lines. Moreover, our observations indicated that 1j–1l decreased the supernatants activity of MMP-2 and MMP-9 more than the others and all of the tested compounds considerably decreased the supernatant levels of MMP-9. The molecular mechanism of 1j binding to MMP-2 and MMP-9 was investigated by fluorescence quenching, absorption spectroscopy, FT-IR, molecular docking and molecular dynamics (MD) simulation procedures.

Nitric Oxide/Cyclic GMP-Dependent Calcium Signalling Mediates IL-6- and TNF-\u03b1-Induced Expression of Glial Fibrillary Acid Protein

Astrocyte activation is characterized by hypertrophy with increased glial fibrillary acidic protein (GFAP), whose expression may involve pro-inflammatory cytokines. In this study, the effects of pro-inflammatory IL-6 and TNF-α and anti-inflammatory cytokines IL-4 and IL-10 on nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) signalling, intracellular calcium concentration ([Ca2+]i) and GFAP expression were investigated. In human glioblastoma astrocytoma U-373 MG cells, IL-6 and TNF-α, but not IL-4 or IL-10, increased iNOS, cGMP, [Ca2+]i and GFAP expression. The inhibitors of iNOS (1400 W), soluble guanylyl cyclase (ODQ) and IP3 receptors (ryanodine and 2-APB) reversed the increase in cGMP or [Ca2+]i, respectively, and prevented GFAP expression. In rat striatal slices, IL-6 and TNF-α, at variance with IL-4 and IL-10, promoted a concentration-dependent increase in Ca2+ efflux, an effect prevented by 1400 W, ODQ and RY/2APB. These data were confirmed by in vivo studies, where IL-6, TNF-α or the NO donor DETA/NO injected in the striatum of anaesthetised rats increased cGMP levels and increased GFAP expression. The present findings point to NO/cGMP-dependent calcium signalling as part of the mechanism mediating IL-6- and TNF-α-induced GFAP expression. As this process plays a fundamental role in driving neurotoxicity, targeting NO/cGMP-dependent calcium signalling may constitute a new approach for therapeutic interventions in neurological disorders.

Physicochemical Characterization and Antioxidant Activity Evaluation of Idebenone/Hydroxypropyl-β-Cyclodextrin Inclusion Complex †.

Idebenone (IDE) is an antioxidant drug active at the level of the central nervous system (CNS), whose poor water solubility limits its clinical application. An IDE/2-hydroxypropyl-β-cyclodextrin (IDE/HP-β-CD) inclusion complex was investigated by combining experimental methods and theoretical approaches. Furthermore, biological in vitro/ex vivo assays were performed. Phase solubility studies showed an AL type diagram, suggesting the presence of a 1:1 complex with high solubility. Scanning electron microscopy (SEM) allowed us to detect the morphological changes upon complexation. The intermolecular interactions stabilizing the inclusion complex were experimentally characterized by exploring the complementarity of Fourier-transform infrared spectroscopy in attenuated total reflectance geometry (FTIR-ATR) with mid-infrared light, Fourier-transform near-infrared (FT-NIR) spectroscopy, and Raman spectroscopy. From the temperature evolution of the O–H stretching band of the complex, the average enthalpy ΔHHB of the hydrogen bond scheme upon inclusion was obtained. Two-dimensional (2D) rotating frame Overhauser effect spectroscopy (ROESY) analysis and computational studies involving molecular modeling and molecular dynamics (MD) simulation demonstrated the inclusion of the quinone ring of IDE inside the CD ring. In vitro/ex vivo studies evidenced that complexation produces a protective effect of IDE against the H2O2-induced damage on human glioblastoma astrocytoma (U373) cells and increases IDE permeation through the excised bovine nasal mucosa.

Synthesis and cytotoxicity of new 2-oxo-7-phenyl-2,3-dihydrothiazolo[4,5-b]pyridine-5-carboxylic acid amides

The synthesis and anticancer activity evaluation of new thiazolo[4,5-b]pyridine-5-carboxylic acid amides is described. The structures of the synthesized compounds were confirmed by spectroscopic data and a single crystal X-ray diffraction analysis for 2.4. The synthesized compounds were screened for their in vitro anticancer activity according to US NCI protocols. The most active 7-(4-fluorophenyl)-2-oxo-2,3-dihydrothiazolo[4,5-b]pyridine-5-carboxylic acid (4-chlorophenyl)amide 2.2 and 7-(4-chlorophenyl)-2-oxo-2,3-dihydrothiazolo[4,5-b]pyridine-5-carboxylic acid (4-chlorophenyl)amide 2.5 were screened for their cytotoxicity effects on C6 Rat glioma cells and U373 Human glioblastoma astrocytoma cells which revealed promising results comparable to temozolamide as reference control according MTT assay data.

Glucose transporter 1-mediated vascular translocation of nanomedicines enhances accumulation and efficacy in solid tumors

Nanomedicine modification with ligands directed to receptors on tumor blood vessels has the potential for selectively enhancing nanomedicine accumulation in malignant tissues by overcoming the vascular barrier of tumors. Nevertheless, the development of broadly applicable ligand approaches capable of promoting the transvascular transport of nanomedicines in a wide spectrum of tumors has been elusive so far. By considering the indispensable and persistent glycolytic fueling of tumors, we developed glucose-installed polymeric micelles loading cisplatin (Gluc-CDDP/m) targeting the glucose transporter 1 (GLUT1), which is overexpressed in most tumors and present on vascular endothelial cells, toward improving the delivery efficiency and therapeutic efficacy. The design of the glucose ligands on Gluc-CDDP/m was engineered to control the conjugation via the carbon 6 of the glucose moieties, as well as the ligand density on the poly (ethylene glycol) (PEG) shell of the micelles. The series of micelles was then studied in vitro and in vivo against GLUT1-high human squamous cell carcinoma of the head and neck OSC-19 cells and GLUT1-low human glioblastoma-astrocytoma U87MG cells. Our results showed that precisely tuning the micelles to have glucose ligands on 25% of their PEG chains increased the efficacy against the tumors by significantly enhancing the tumor accumulation, even in GLUT1-low U87MG tumors. The enhancement of the intratumoral levels of these micelles was hindered by concomitant administration of glucose, or the GLUT1 inhibitor STF-31, confirming a GLUT1/glucose-mediated increment of the accumulation. Intravital confocal laser scanning microscopy imaging of tumor tissues further demonstrated the rapid extravasation and penetration of Gluc-CDDP/m in OSC-19 tumors compared to non-targeted CDDP/m. These findings indicate GLUT1-targeting as a promising approach for overcoming the vascular barrier and boosting the delivery of nanomedicine in tumors.

Biological Evaluation of the NIR‐Emissive Ruby Analogue [Cr(ddpd)2][BF4]3 as a Photodynamic Therapy Photosensitizer

Photodynamic therapy relies on the bioavailability of photosensitizers with suitable photophysical, chemical, and biochemical properties. Although the photophysical properties, stability, and high water solubility of the chromium(III) complex [Cr(ddpd)2][BF4]3 (ddpd = N,N′‐dimethyl‐N,N′‐dipyridin‐2‐ylpyridine‐2,6‐diamine) are very favorable, its photocytotoxicity against cancerous and non‐cancerous cell lines has not yet been elucidated. We now report the cytotoxicity and photocytotoxicity of the complex [Cr(ddpd)2][BF4]3 against human cervical cancer cells, human primary glioblastoma cells, human glioblastoma astrocytoma cells, and non‐cancerous retinal pigment epithelium cells.

Cytotoxicity and antibacterial activities of new chemically synthesized magnetic nanoparticles containing eugenol

In recent years, the use of magnetic nanoparticles (MNPs) has increased dramatically for targeted drug delivery. Also, nanoparticles increase the effectiveness of drugs due to increased drug loading capacity. Eugenol (EUG) is the major component of clove oil which has a wide range of therapeutic effects. In this work, magnetic nanoparticles containing eugenol were prepared to enhance the therapeutic properties of eugenol. First, Fe3O4 magnetic nanoparticles (MNPs) were synthesized through chemical co-precipitation reaction and their surface was coated with silica by sol-gel process. Then, the surface of Fe3O4@SiO2 MNPs was coated by eugenol. γ-Fe2O3@SiO2-EUG MNPs were characterized by fourier transform infrared spectroscopy (FT-IR) and transmission electron microscopy (TEM) which indicate effective coating of magnetic nanoparticles with silica and eugenol and spherical shape of the nanoparticles with an average diameter of 15 nm. Comparison of in vitro cytotoxicity of γ-Fe2O3@SiO2-EUG MNPs and EUG versus three lines of human cancer cells (human glioblastoma astrocytoma, human lung carcinoma, and human ovarian carcinoma) showed that the cytotoxicity of the nanoparticles was significantly higher than EUG specially about human ovarian carcinoma (IC50 25.34 μg/mL compared with IC50 100.57 μg/mL for EUG) while Fe3O4@SiO2 MNPs did not show cytotoxicity at used concentrations. Antibacterial assays were carried out on Staphylococcus aureus, Escherichia coli (E. coli), Klebsiella pneumonia, and Acinetobacter baumannii which exhibited the inhibition zone for γ-Fe2O3@SiO2-EUG MNPs is larger than free eugenol indicating better antibacterial activity γ-Fe2O3@SiO2-EUG MNPs as compared with EUG.

Arginylglycylaspartic Acid-Surface-Functionalized Doxorubicin-Loaded Lipid-Core Nanocapsules as a Strategy to Target Alpha(V) Beta(3) Integrin Expressed on Tumor Cells.

Doxorubicin (Dox) clinical use is limited by dose-related cardiomyopathy, becoming more prevalent with increasing cumulative doses. Previously, we developed Dox-loaded lipid-core nanocapsules (Dox-LNC) and, in this study, we hypothesized that self-assembling and interfacial reactions could be used to obtain arginylglycylaspartic acid (RGD)-surface-functionalized-Dox-LNC, which could target tumoral cells overexpressing αvβ3 integrin. Human breast adenocarcinoma cell line (MCF-7) and human glioblastoma astrocytoma (U87MG) expressing different levels of αvβ3 integrin were studied. RGD-functionalized Dox-LNC were prepared with Dox at 100 and 500 mg·mL−1 (RGD-MCMN (Dox100) and RGD-MCMN (Dox500)). Blank formulation (RGD-MCMN) had z-average diameter of 162 ± 6 nm, polydispersity index of 0.11 ± 0.04, zeta potential of +13.2 ± 1.9 mV and (6.2 ± 1.1) × 1011 particles mL−1, while RGD-MCMN (Dox100) and RGD-MCMN (Dox500) showed respectively 146 ± 20 and 215 ± 25 nm, 0.10 ± 0.01 and 0.09 ± 0.03, +13.8 ± 2.3 and +16.4 ± 1.5 mV and (6.9 ± 0.6) × 1011 and (6.1 ± 1.0) × 1011 particles mL−1. RGD complexation was 7.73 × 104 molecules per nanocapsule and Dox loading were 1.51 × 104 and 7.64 × 104 molecules per nanocapsule, respectively. RGD-functionalized nanocapsules had an improved uptake capacity by U87MG cells. Pareto chart showed that the cell viability was mainly affected by the Dox concentration and the period of treatment in both MCF-7 and U87MG. The influence of RGD-functionalization on cell viability was a determinant factor exclusively to U87MG.

Anti‑inflammatory actions of gabapentin and pregabalin on the substance P‑induced mitogen‑activated protein kinase activation in U373 MG human glioblastoma astrocytoma cells.

Gabapentin (GBP) and pregabalin (PGB) exert antinociceptive effects on chronic nociceptive responses with neuropathic or inflammatory conditions. Furthermore, it is considered that GBP and PGB exhibit anti‑inflammatory effects by modulating the substance P (SP)‑mediated neurokinin‑1 receptor (NK1R; a SP receptor) response. Thus, in the present study, the effects of GBP and PGB on SP‑induced activation were investigated in the human glioblastoma astrocytoma U373 MG cell line, which expresses high levels of functional high‑affinity NK1R, and produces interleukin (IL)‑6 and IL‑8 in response to SP. The results indicated that GBP and PGB suppressed the SP‑induced production of IL‑6, and IL‑8 in U373 MG cells. Furthermore, GBP and PGB inhibited the SP‑induced phosphorylation of p38 mitogen‑activated protein kinase (MAPK) and nuclear factor (NF)‑κB, and the nuclear translocation of NF‑κB in U373 MG cells. Together, these observations suggest that GBP and PGB likely prevent SP‑induced IL‑6 and IL‑8 production in U373 MG cells via the inhibition of signaling molecules, including p38 MAPK and NF‑κB, thereby exhibiting antineuroinflammatory effects.

Hydrogen sulfide generation from l-cysteine in the human glioblastoma-astrocytoma U-87 MG and neuroblastoma SHSY5Y cell lines.

Hydrogen sulfide (H2S) is endogenously synthesized from l-cysteine in reactions catalyzed by cystathionine beta-synthase (CBS, EC 4.2.1.22) and gamma-cystathionase (CSE, EC 4.4.1.1). The role of 3-mercaptopyruvate sulfurtransferase (MPST, EC 2.8.1.2) in H2S generation is also considered; it could be important for tissues with low CTH activity, e.g. cells of the nervous system. The expression and activity of CBS, CTH, and MPST were detected in the human glioblastoma-astrocytoma (U-87 MG) and neuroblastoma (SHSY5Y) cell lines. In both cell lines, the expression and activity of MPST were the highest among the investigated enzymes, suggesting its possible role in the generation of H2S. The RP-HPLC method was used to determine the concentration of cystathionine and alpha-ketobutyrate, products of the CBS- and CTH-catalyzed reactions. The difference in cystathionine levels between cell homogenates treated with totally CTH-inhibiting concentrations of dl-propargylglycine and without the inhibitor was used to evaluate the activity of CBS. The higher expression and activity of CBS, CTH and MPST in the neuroblastoma cells were associated with more intensive generation of H2S in the presence of 2 mM cysteine. A threefold higher level of sulfane sulfur, a potential source of hydrogen sulfide, was detected in the astrocytoma cells in comparison to the neuroblastoma cells.

Synthesis, Structure Elucidation and Cytotoxicity of (+)-Usnic Acid Derivatives on U87MG Glioblastoma Cells

A series of new usnic acid ketamine compounds [1-8] and their oxime analogues [9-12] were synthesized by reacting (+)-usnic acid with various amines and subsequent treatment with hydroxylamine hydrochloride. They were evaluated on the human glioblastoma-astrocytoma cell line (U87MG) by a MTT assay for cell viability in vitro. The ketamine-derivatives (Schiff bases) show significant cytotoxicity on U87MG cells. A novel N-heterocyclic derivative (1,4-diazepine) showed an interesting tautomeric structure and displayed more activity on cancer cell line than (+)-usnic acid itself.

High Fat Diet and Inflammation - Modulation of Haptoglobin Level in Rat Brain.

Obesity and dietary fats are well known risk factors for the pathogenesis of neurodegenerative diseases. The analysis of specific markers, whose brain level can be affected by diet, might contribute to unveil the intersection between inflammation/obesity and neurodegeneration. Haptoglobin (Hpt) is an acute phase protein, which acts as antioxidant by binding free haemoglobin (Hb), thus neutralizing its pro-oxidative action. We previously demonstrated that Hpt plays critical functions in brain, modulating cholesterol trafficking in neuroblastoma cell lines, beta-amyloid (Aβ) uptake by astrocyte, and limiting Aβ toxicity on these cells. A major aim of this study was to evaluate whether a long term (12 or 24 weeks) high-fat diet (HFD) influences Hpt and Hb expression in rat hippocampus. We also assessed the development of obesity-induced inflammation by measuring hippocampal level of TNF-alpha, and the extent of protein oxidation by titrating nitro-tyrosine (N-Tyr). Hpt concentration was lower (p < 0.001) in hippocampus of HFD rats than in control animals, both in the 12 and in the 24 weeks fed groups. HFD was also associated in hippocampus with the increase of Hb level (p < 0.01), inflammation and protein oxidative modification, as evidenced by the increase in the concentration of TNF-alpha and nitro-tyrosine. In fact, TNF-alpha concentration was higher in rats receiving HFD for 12 (p < 0.01) or 24 weeks (p < 0.001) compared to those receiving the control diet. N-Tyr concentration was more elevated in hippocampus of HFD than in control rats in both 12 weeks (p = 0.04) and 24 weeks groups (p = 0.01), and a positive correlation between Hb and N-Tyr concentration was found in each group. Finally, we found that the treatment of the human glioblastoma-astrocytoma cell line U-87 MG with cholesterol and fatty acids, such as palmitic and linoleic acid, significantly impairs (p < 0.001) Hpt secretion in the extracellular compartment. We hypothesize that the HFD-dependent decrease of Hpt in hippocampus, as associated with Hb increase, might enhance the oxidative stress induced by free Hb. Altogether our data, identifying Hpt as a molecule modulated in the brain by dietary fats, may represent one of the first steps in the comprehension of the molecular mechanisms underlying the diet-related effects in the nervous system.

Zoledronic acid induces apoptosis via stimulating the expressions of ERN1, TLR2, and IRF5 genes in glioma cells.

Glioblastoma multiforme (GBM) is the most common and aggressive brain tumor that affects older people. Although the current therapeutic approaches for GBM include surgical resection, radiotherapy, and chemotherapeutic agent temozolomide, the median survival of patients is 14.6months because of its aggressiveness. Zoledronic acid (ZA) is a nitrogen-containing bisphosphonate that exhibited anticancer activity in different cancers. The purpose of this study was to assess the potential effect of ZA in distinct signal transduction pathways in U87-MG cells. In this study, experiments performed on U87-MG cell line (Human glioblastoma-astrocytoma, epithelial-like cell line) which is an in vitro model of human glioblastoma cells to examine the cytotoxic and apoptotic effects of ZA. IC50 dose of ZA, 25μM, applied on U87-MG cells during 72h. ApoDIRECT In Situ DNA Fragmentation Assay was used to investigate apoptosis of U87MG cells. The quantitative reverse transcription polymerase chain reaction (qRT-PCR) (LightCycler480 System) was carried out for 48 gene expression like NF-κB, Toll-like receptors, cytokines, and inteferons. Our results indicated that ZA (IC50 dose) increased apoptosis 1.27-fold in U87MG cells according to control cells. According to qRT-PCR data, expression levels of the endoplasmic reticulum-nuclei-1 (ERN1), Toll-like receptor 2 (TLR2), and human IFN regulatory factor 5 (IRF5) tumor suppressor genes elevated 2.05-, 2.08-, and 2.3-fold by ZA, respectively, in U87MG cells. Our recent results indicated that ZA have a key role in GBM progression and might be considered as a potential agent in glioma treatment.

Pax6 influences expression patterns of genes involved in neuro- degeneration.

Pax6, a highly conserved multifunctional transcription factor, has been critical for neurogenesis and neuronal plasticity. It is presumed that if level of Pax6 approaches either low or null, critical genes responsible for maintaining functional status of neurons or glia would be modulated. Therefore, it has been intended to explore possibility of either direct or indirect influence of Pax6 in neurodegeneration. The cell lines having origin of murine embryonic fibroblast (Pax6-non expressing, NIH3T3-cell line), murine neuroblastoma (Pax6-expressing brain-derived, Neuro-2a-cell line), and human glioblastoma-astrocytoma (U87MG) were cultured and maintained in a CO2 incubator at 37°C and 5% CO2 in DMEM containing 10% fetal bovine serum. The knockdown of endogenous Pax6 in Neuro-2a cells was achieved through siRNA based gene knock-down approach. The efficiency and validation of knock-down was done by real time PCR. The knock-down of Pax6 was successfully achieved. The levels of expression of transcripts of some of the proposed putative markers of neurodegeneration like Pax6, S100β, GFAP, BDNF, NGN2, p73α, p73δ, LDH, SOD, and Catalase were analyzed in Pax6 knockdown condition for analysis of role of Pax6 in neurodegeneration. Since the Pax6 has been proposed to bind to promoter sequences of catalase, and catalase suppresses TGFβ, relative lower levels of catalase in Neuro-2a and U-87MG as compared to NIH-3T3 indicates a possible progressive dominant negative impact of Pax6. However, presence of SOD and LDH indicates alternative protective mechanism. Presence of BDNF and TGFβ indicates association between them in glioblastoma-astrocytoma. Therefore, Pax6 seems to be involved directly with p53 and TGFβ mediated pathways and indirectly with redox-sensitive pathway regulation. The neurodegenerative markers S100β, GFAP, BDNF, NGN2, p73α, p73δ, observed downregulated in Pax6 knockdown condition suggest Pax6-mediated regulation of these markers. Observations enlighten Pax6-mediated influences on cascades of genes involved in growth, differentiation and maturation of neurons and glia.