Bilitranslocase and anthocyanins role in the gastrointestinal tract

Bilitranslocase (BTL) is a organic anion transporter expressed in liver and in several extra-hepatic tissues. This membrane protein transports different substrates as pyrrolic molecules, nucleotides, flavonoids. Anthocyanins, one of the most represented flavonoids class are known to have antioxidant activity. They act as anti-inflammatory, anti-cancer and anti-proliferative molecules by interfering with different intracellular pathways. Some chronic colon diseases results in an increase in the pro-inflammatory machinery that are associated with a 5-fold increased risk of developing colon cancer. The expression and the role of BTL in the gastrointestinal tract in normal and pathological condition, as well as its role as anthocyanins transporter in colon cancer cells will be take into account in Trans2care project

LA FOSFOLIPIDE IDROPEROSSIDO GLUTATIONE PEROSSIDASI -PHGPX- E ALTRI MECCANISMI ANTIOSSIDATIVI NELL'APPARATO RIPRODUTTORE MASCHILE DEL RATTO

1999/2000XII Ciclo1967Versione digitalizzata della tesi di dottorato cartacea

Dietary Anthocyanins: Impact on Colorectal Cancer and Mechanisms of Action

5-nonemixedTramer F.; Moze S.; Ademosun A.O.; Passamonti S.; Cvorovic J.Tramer, Federica; Moze, S.; Ademosun, A. O.; Passamonti, Sabina; Cvorovic, Jovan

A preliminary study on the role of Piezo1 channels in myokine release from cultured mouse myotubes

It has long been known that regular physical exercise induces short and long term benefits reducing the risk of cardiovascular disease, diabetes, osteoporosis, cancer and improves sleep quality, cognitive level, mobility, autonomy in enderly. More recent is the evidence on the endocrine role of the contracting skeletal muscle. Exercise triggers the release of miokines, which act in autocrine, paracrine and endocrine ways controlling the activity of muscles but also of other tissues and organs such as adipose tissue, liver, pancreas, bones, and brain. The mechanism of release is still unclear. Neuromuscular electrical stimulation reproduces the beneficial effects of physical activity producing physiological metabolic, cardiovascular, aerobic responses consistent with those induced by exercise. In vitro, Electrical Pulse Stimulations (EPS) of muscle cells elicit cell contraction and mimic miokine release in the external medium. Here we show that, in cultured mouse myotubes, EPS induce contractile activity and the release of the myokine IL-6. Gadolinium highly reduces EPS-induced IL-6 release, suggesting the involvement of mechanical activated ion channels. The chemical activation of mechanosensitive Piezo1 channels with the specific agonist Yoda1 stimulates IL-6 release similarly to EPS, suggesting the involvement of Piezo1 channels in the control of the myokine release. The expression of Piezo1 protein in myotubes was confirmed by the Western blot analysis. To the best of our knowledge, this is the first evidence of a Piezo1-mediated effect in myokine release and suggests a potential translational use of specific Piezo1 agonists for innovative therapeutic treatments reproducing/enhancing the benefits of exercise mediated by myokines

Nanoscale Bilirubin Analysis in Translational Research and Precision Medicine by the Recombinant Protein HUG

Bilirubin is a toxicological biomarker for hemolysis and liver diseases. The current automated diazo method used in clinical chemistry has limited applicability in rodent models and cannot be used in small animals relevant to toxicology, microphysiological systems, cell cultures, and kinetic studies. Here, we present a versatile fluorometric method for nanoscale analysis of bilirubin based on its highly specific binding to the recombinant bifunctional protein HELP–UnaG (HUG). The assay is sensitive (LoQ = 1.1 nM), accurate (4.5% relative standard error), and remarkably robust, allowing analysis at pH 7.4–9.5, T = 25–37 °C, in various buffers, and in the presence of 0.4–4 mg × L−1 serum albumin or 30% DMSO. It allows repeated measurements of bilirubinemia in murine models and small animals, fostering the 3Rs principle. The assay determines bilirubin in human plasma with a relative standard error of 6.7% at values that correlate and agree with the standard diazo method. Furthermore, it detects differences in human bilirubinemia related to sex and UGT1A1 polymorphisms, thus demonstrating its suitability for the uniform assessment of bilirubin at the nanoscale in translational and precision medicine

Phenolics from grapefruit peels inhibit HMG-CoA reductase and angiotensin-I converting enzyme and show antioxidative properties in endothelial EA.Hy 926 cells

This study sought to investigate the possible mechanisms for the use of phenolic extracts from grapefruit peels in the management/prevention of cardiovascular complications. The effects of the phenolic extracts on key enzymes relevant to cardiovascular diseases [3-hydroxy-methyl-3-glutaryl coenzyme A reductase (HMG-CoA reductase) and angiotensin-I converting enzyme (ACE)], cellular antioxidant activity in human endothelial cells (EA.Hy 926) and radicals [1,1-diphenyl-2 picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS)] scavenging abilities were investigated. The phenolic contents of the extracts were investigated using HPLC–DAD. There was no significant (P > 0.05) difference in the HMG-CoA reductase inhibitory ability of the two extracts, while the bound phenolic extracts had a stronger ACE inhibitory ability than the soluble free phenolics. The extracts also showed intracellular antioxidant activity in human endothelial (EA.Hy 926) cells. Furthermore, the bound phenolics had significantly higher radicals (DPPH* and ABTS*) scavenging abilities than the free phenolics. The HPLC analysis revealed the presence of flavonoids (quercetin and kaempferol), phenolics acids (resveratrol, gallic acid, ellagic acid and caffeic acid) and tannin (catechin). The cellular antioxidative properties and inhibition of enzymes relevant to the management of cardiovascular complications showed that grapefruit peels could be used as nutraceuticals for the management of such conditions

Cyanidin 3-glucoside targets a hepatic bilirubin transporter in rats

One of the organ-specific functions of the liver is the excretion of bilirubin into the bile. Membrane transport of bilirubin from the blood to the liver is not only an orphan function, because there is no link to the protein/gene units that perform this function, but also a poorly characterised function. The aim of this study was to investigate the pharmacology of bilirubin uptake in the liver of the female Wistar rat to improve basic knowledge in this neglected area of liver physiology. We treated isolated perfused livers of female rats with repeated single-pass, albumin-free bilirubin boli. We monitored both bilirubin and bilirubin glucuronide in perfusion effluent with a bio-fluorometric assay. We tested the ability of nine molecules known as substrates or inhibitors of sinusoidal membrane transporters to inhibit hepatic uptake of bilirubin. We found that cyanidin 3-glucoside and malvidin 3-glucoside were the only molecules that inhibited bilirubin uptake. These dietary anthocyanins resemble bro-mosulfophthalein (BSP), a substrate of several sinusoidal membrane transporters. The SLCO-specific substrates estradiol-17 beta-glucuronide, pravastatin, and taurocholate inhibited only bilirubin glucuronide uptake. Cya-nidin 3-glucoside and taurocholate acted at physiological concentrations. The SLC22-specific substrates indo-methacin and ketoprofen were inactive. We demonstrated the existence of a bilirubin-glucuronide transporter inhibited by bilirubin, a fact reported only once in the literature. The data suggest that bilirubin and bilirubin glucuronide are transported to the liver via pharmacologically distinct membrane transport pathways. Some dietary anthocyanins may physiologically modulate the uptake of bilirubin into the liver

1,4-dihydroxy quininib activates ferroptosis pathways in metastatic uveal melanoma and reveals a novel prognostic biomarker signature

Uveal melanoma (UM) is an ocular cancer, with propensity for lethal liver metastases. When metastatic UM (MUM) occurs, as few as 8% of patients survive beyond two years. Efficacious treatments for MUM are urgently needed. 1,4-dihydroxy quininib, a cysteinyl leukotriene receptor 1 (CysLT1) antagonist, alters UM cancer hallmarks in vitro, ex vivo and in vivo. Here, we investigated the 1,4-dihydroxy quininib mechanism of action and its translational potential in MUM. Proteomic profiling of OMM2.5 cells identified proteins differentially expressed after 1,4-dihydroxy quininib treatment. Glutathione peroxidase 4 (GPX4), glutamate-cysteine ligase modifier subunit (GCLM), heme oxygenase 1 (HO-1) and 4 hydroxynonenal (4-HNE) expression were assessed by immunoblots. Biliverdin, glutathione and lipid hydroperoxide were measured biochemically. Association between the expression of a specific ferroptosis signature and UM patient survival was performed using public databases. Our data revealed that 1,4-dihydroxy quininib modulates the expression of ferroptosis markers in OMM2.5 cells. Biochemical assays validated that GPX4, biliverdin, GCLM, glutathione and lipid hydroperoxide were significantly altered. HO-1 and 4-HNE levels were significantly increased in MUM tumor explants from orthotopic patient-derived xenografts (OPDX). Expression of genes inhibiting ferroptosis is significantly increased in UM patients with chromosome 3 monosomy. We identified IFerr, a novel ferroptosis signature correlating with UM patient survival. Altogether, we demontrated that in MUM cells and tissues, 1,4-dihydroxy quininib modulates key markers that induce ferroptosis, a relatively new type of cell death driven by iron-dependent peroxidation of phospholipids. Furthermore, we showed that high expression of specific genes inhibiting ferroptosis is associated with a worse UM prognosis, thus, the IFerr signature is a potential prognosticator for which patients develop MUM. All in all, ferroptosis has potential as a clinical biomarker and therapeutic target for MUM