Search results for "Spectroscopy"
showing 10 items of 10293 documents
VEGF-R2/Caveolin-1 Pathway of Undifferentiated ARPE-19 Retina Cells: A Potential Target as Anti-VEGF-A Therapy in Wet AMD by Resvega, an Omega-3/Poly…
2021
Age-related macular degeneration (AMD) is one of the main causes of deterioration in vision in adults aged 55 and older. In spite of therapies, the progression of the disease is often observed without reverse vision quality. In the present study, we explored whether, in undifferentiated ARPE-19 retinal cells, a disruption of the VEGF receptors (VEGF-R)/caveolin-1 (Cav-1)/protein kinases pathway could be a target for counteracting VEGF secretion. We highlight that Resvega®, a combination of omega-3 fatty acids with an antioxidant, resveratrol, inhibits VEGF-A secretion in vitro by disrupting the dissociation of the VEGF-R2/Cav-1 complex into rafts and subsequently preventing MAPK activation.…
Targeting Angiogenesis in Biliary Tract Cancers: An Open Option
2017
Abstract: Biliary tract cancers (BTCs) are characterized by a bad prognosis and the armamentarium of drugs for their treatment is very poor. Although the inflammatory status of biliary tract represents the first step in the cancerogenesis, the microenvironment also plays a key role in the pathogenesis of BTCs, promoting tumor angiogenesis, invasion and metastasis. Several molecules, such as vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF), are involved in the angiogenesis process and their expression on tumor samples has been explored as prognostic marker in both cholangiocarcinoma and gallbladder cancer. Recent studies evaluated the genomic landscape of BTCs and…
The Role of ERK Signaling in Experimental Autoimmune Encephalomyelitis
2017
Extracellular signal-regulated kinase (ERK) signaling plays a crucial role in regulating immune cell function and has been implicated in autoimmune disorders. To date, all commercially available inhibitors of ERK target upstream components, such as mitogen-activated protein (MAP) kinase/ERK kinase (MEKs), but not ERK itself. Here, we directly inhibit nuclear ERK translocation by a novel pharmacological approach (Glu-Pro-Glu (EPE) peptide), leading to an increase in cytosolic ERK phosphorylation during T helper (Th)17 cell differentiation. This was accompanied by diminished secretion of granulocyte-macrophage colony-stimulating factor (GM-CSF), a cytokine influencing the encephalitogenicity …
19F NMR as a versatile tool to study membrane protein structure and dynamics.
2019
Abstract To elucidate the structures and dynamics of membrane proteins, highly advanced biophysical methods have been developed that often require significant resources, both for sample preparation and experimental analyses. For very complex systems, such as membrane transporters, ion channels or G-protein coupled receptors (GPCRs), the incorporation of a single reporter at a select site can significantly simplify the observables and the measurement/analysis requirements. Here we present examples using 19F nuclear magnetic resonance (NMR) spectroscopy as a powerful, yet relatively straightforward tool to study (membrane) protein structure, dynamics and ligand interactions. We summarize meth…
Anti-Cancer Activity of Resveratrol and Derivatives Produced by Grapevine Cell Suspensions in a 14 L Stirred Bioreactor
2017
International audience; In the present study, resveratrol and various oligomeric derivatives were obtained from a 14 L bioreactor culture of elicited grapevine cell suspensions (Vitis labrusca L.). The crude ethyl acetate stilbene extract obtained from the culture medium was fractionated by centrifugal partition chromatography (CPC) using a gradient elution method and the major stilbenes contained in the fractions were subsequently identified by using a (13)C-NMR-based dereplication procedure and further 2D NMR analyses including HSQC, HMBC, and COSY. Beside δ-viniferin (2), leachianol F (4) and G (4'), four stilbenes (resveratrol (1), ε-viniferin (5), pallidol (3) and a newly characterized…
Cytotoxicity of Labruscol, a New Resveratrol Dimer Produced by Grapevine Cell Suspensions, on Human Skin Melanoma Cancer Cell Line HT-144
2017
IF 2.861; International audience; A new resveratrol dimer (1) called labruscol, has been purified by centrifugal partition chromatography of a crude ethyl acetate stilbene extract obtained from elicited grapevine cell suspensions of Vitis labrusca L. cultured in a 14-liter stirred bioreactor. One dimensional (1D) and two dimensional (2D) nuclear magnetic resonance (NMR) analyses including ¹H, 13C, heteronuclear single-quantum correlation (HSQC), heteronuclear multiple bond correlation (HMBC), and correlation spectroscopy (COSY) as well as high-resolution electrospray ionisation mass spectrometry (HR-ESI-MS) were used to characterize this compound and to unambiguously identify it as a new st…
The Commensal Microbiota Enhances ADP-Triggered Integrin αIIbβ3 Activation and von Willebrand Factor-Mediated Platelet Deposition to Type I Collagen
2020
The commensal microbiota is a recognized enhancer of arterial thrombus growth. While several studies have demonstrated the prothrombotic role of the gut microbiota, the molecular mechanisms promoting arterial thrombus growth are still under debate. Here, we demonstrate that germ-free (GF) mice, which from birth lack colonization with a gut microbiota, show diminished static deposition of washed platelets to type I collagen compared with their conventionally raised (CONV-R) counterparts. Flow cytometry experiments revealed that platelets from GF mice show diminished activation of the integrin αIIbβ3 (glycoprotein IIbIIIa) when activated by the platelet agonist adenosine diphosphate (ADP). Fu…
TRPM8 Channel Activation Reduces the Spontaneous Contractions in Human Distal Colon
2020
The transient receptor potential-melastatin 8 (TRPM8) is a non-selective Ca2+-permeable channel, activated by cold, membrane depolarization, and different cooling compounds. TRPM8 expression has been found in gut mucosal, submucosal, and muscular nerve endings. Although TRPM8 plays a role in pathological conditions, being involved in visceral pain and inflammation, the physiological functions in the digestive system remain unclear as yet. The aims of the present study were: (i) to verify the TRPM8 expression in human distal colon
Noninvasive optical diagnostics of enhanced green fluorescent protein expression in skeletal muscle for comparison of electroporation and sonoporatio…
2015
We highlight the options available for noninvasive optical diagnostics of reporter gene expression in mouse tibialis cranialis muscle. An in vivo multispectral imaging technique combined with fluorescence spectroscopy point measurements has been used for the transcutaneous detection of enhanced green fluorescent protein (EGFP) expression, providing information on location and duration of EGFP expression and allowing quantification of EGFP expression levels. For EGFP coding plasmid (pEGFP-Nuc Vector, 10 μg/50 ml 10 μg/50 ml ) transfection, we used electroporation or ultrasound enhanced microbubble cavitation [sonoporation (SP)]. The transcutaneous EGFP fluorescence in live mice was monit…
Vitamin D Status and the Relationship with Bone Fragility Fractures in HIV-Infected Patients: A Case Control Study
2018
HIV-infected patients show high risk of fracture. The aims of our study were to determine the prevalence of vertebral fractures (VFs) and their associations with vitamin D in HIV patients. 100 patients with HIV infection and 100 healthy age-and sex-matched controls were studied. Bone mineral density was measured by quantitative ultrasound at the non-dominant heel. Serum osteocalcin and C-terminal telopeptide of collagen type 1 served as bone turnover markers. Bone ultrasound measurements were significantly lower in patients compared with controls (Stiffness Index (SI): 80.58 ± 19.95% vs. 93.80 ± 7.10%, respectively, p < 0.001). VFs were found in 16 patients and in 2 controls. HIV patie…