30 research outputs found
Barley-ß-glucans reduce systemic inflammation, renal injury and aortic calcification through ADAM17 and neutral-sphingomyelinase2 inhibition
In chronic kidney disease (CKD), hyperphosphatemia-induced inflammation aggravates vascular calcification (VC) by increasing vascular smooth muscle cell (VSMC) osteogenic differentiation, ADAM17-induced renal and vascular injury, and TNFα-induction of neutral-sphingomyelinase2 (nSMase2) to release pro-calcifying exosomes. This study examined anti-inflammatory β-glucans efficacy at attenuating systemic inflammation in health, and renal and vascular injury favoring VC in hyperphosphatemic CKD. In healthy adults, dietary barley β-glucans (Bβglucans) reduced leukocyte superoxide production, inflammatory ADAM17, TNFα, nSMase2, and pro-aging/pro-inflammatory STING (Stimulator of interferon genes) gene expression without decreasing circulating inflammatory cytokines, except for γ-interferon. In hyperphosphatemic rat CKD, dietary Bβglucans reduced renal and aortic ADAM17-driven inflammation attenuating CKD-progression (higher GFR and lower serum creatinine, proteinuria, kidney inflammatory infiltration and nSMase2), and TNFα-driven increases in aortic nSMase2 and calcium deposition without improving mineral homeostasis. In VSMC, Bβglucans prevented LPS- or uremic serum-induced rapid increases in ADAM17, TNFα and nSMase2, and reduced the 13-fold higher calcium deposition induced by prolonged calcifying conditions by inhibiting osteogenic differentiation and increases in nSMase2 through Dectin1-independent actions involving Bβglucans internalization. Thus, dietary Bβglucans inhibit leukocyte superoxide production and leukocyte, renal and aortic ADAM17- and nSMase2 gene expression attenuating systemic inflammation in health, and renal injury and aortic calcification despite hyperphosphatemia in CKD.A grant to A.S.D. and M.J.M. from IRBLleida and Agrotecnio Research collaborative projects from the Consell Social at Lleida University supported initial work, Instituto de Salud Carlos III and co-funded by European Union (ERDF/FEDER) (FIS PI11/00259, PI14/01452, PI17/02181), Plan de Ciencia, Tecnología e Innovación 2013–2017 y 2018–2022 del Principado de Asturias (GRUPIN14-028, IDI-2018-000152), RedInRen from ISCIII (ISCIII-RETIC REDINREN RD16/0009). Investigator support included: NC-L by GRUPIN14-028 and IDI-2018-000152, LM-A by GRUPIN14-028, SP by FICYT; MVA and PV by Educational Grant 2 A/2015 from ERA-EDTA CKD-MBD Working Group; PV and AC by ERA-EDTA fellowships 2011 and 2012; JR-C by MINECO (“Juan de la Cierva” program, FJCI-2015-23849); A.S.D. by Asociación Investigación de Fisiología Aplicada. A.S.D. and M.J.M. are members of the Campus Iberus (Ebro Valley Campus of International Excellence)
Role of vitamin D signalling in vascular smooth muscle cells - morphological and molecular study
La vitamina D ha estat durant molt de temps coneguda pel seu important paper en laregulacio dels nivells de calci i fosfor, i en la mineralitzacio de l'os. Els efectes biologics de laforma hormonalment activa de vitamina D (1,25(OH)2D3, o calcitriol) estan mediats per launio al receptor de vitamina D (VDR), que alhora actua sobre els elements de respostaespecifics (VDRE) en el promotor dels gens diana de vitamina D, modificant-ne l'expressio.En les ultimes decades, s'ha demostrat que el VDR no solament es present en les dianesclassiques de la vitamina D com els ossos, els ronyons i l'intesti, sino tambe en molts altresteixits, com els musculs esqueletics, llisos, i cardiacs, i tambe en el cervell, la pell i el fetge.A mes del control de l'homeostasi mineral, la vitamina D exerceix accions pleiotropiques endiferents tipus cel.lulars, influint en processos fisiologics importants com la proliferacio, ladiferenciacio cel.lular, la resposta immune, aixi com tambe en les diferents condicionspatologiques: el cancer, les malalties cardiovasculars, metaboliques i autoimmunes. A mes,juntament amb els seus efectes endocrins, la vitamina D te funcions importantsautocrines/paracrines. En les cel.lules de muscul llis vascular (CMLV), la vitamina D regula laproliferacio i la calcificacio, aquests dos processos, juntament amb la senescencia de lesCMLV es produeixen durant el proces aterosclerotic. Per poder-se dividir, les CMLVnecessiten l'energia de l'ATP produida per les mitocondries. Les alteracions de la funciomitocondrial estan relacionades amb una major produccio de radicals lliures. A la paretarterial, l'angiotensina II (Ang II) actua com un potent mediador d'estres oxidatiu, provocantsenescencia prematura induida per l'estres (SIPS). Els nivells d'Ang II son controlats per larenina, l'expressio de la qual es regulada per la vitamina D. Per tant, un defecte en lasenyalitzacio de la vitamina D pot conduir a un augment en els nivells d'Ang II i produir elsseus efectes adversos en la paret de l'arteria.Quan es van cultivar les CMLV, obtingudes de ratolins knockout per VDR (VDRKO) esva trobar un augment en la produccio d'Ang II en el medi de cultiu d'aquestes cel.lules encomparacio amb el tipus salvatge (WT), que estava d'acord amb la major activacio delsistema renina-angiotensina a nivell sistemic, que es va trobar en els ratolins mutants deVDR. D'una banda, una disminucio en les taxes de proliferacio de les CMLV VDRKO es vatrobar in vitro i in vivo. Aquest descens va ser en paral.lel a un augment en el volumcel.lular. En estat de repos, les cel.lules VDRKO presentaven un augment significatiu del'expressio de p57Kip2 juntament amb els nivells elevats de p19Arf, p21Cip1 i p27Kip1, i nivellsinferiors de PRB fosforilada, ciclines D i E, i axi es preve la seva proliferacio. A mes, lescel.lules VDRKO van mostrar un augment en l'expressio de la catepsina D, un enzim ambactivitat com renina, i del receptor d'Ang II tipus 1. A mes, la produccio d'anio superoxid vaser major en les cel.lules mutants, i va ser inhibida tant amb losartan com amb DPI. D'altrabanda, les cel.lules VDRKO presenten una disminucio significativa en l'expressio de l'enzimmitocondrial antioxidant, la superoxid dismutasa de manganes (SOD2) i l'oxid nitric sintetasainduible que produeix la molecula vasodilatadora NO,. Per respirometria d'alta resolucio es vadeterminar que les mitocondries de VDRKO CMLV van ser menys eficients que podria explicarel menor contingut d'ATP en aquestes cel.lules. Tots aquests factors es van relacionar amb elfenotip senescent, que presentaven al voltant del 20% de les CMLV sense VDR en cultiu.En conclusio, l'absencia de senyalitzacio per VDR en CMLV porta a SIPS causada perl'augment en la produccio local d'Ang II, amb el conseguent augment dels radicals lliures,produits per l'activacio de la NADPH oxidasa, el que suggereix un possible paper del sistemade la vitamina D en malalties vasculars, que mostren una hiperproliferacio de les CMLV. La vitamina D ha sido durante mucho tiempo conocida por su importante papel en laregulacion de los niveles de calcio y fosforo, y en la mineralizacion del hueso. Los efectosbiologicos de la forma hormonalmente activa de la vitamina D (1,25(OH)2D3, o calcitriol)estan mediados por la union al receptor de la vitamina D (VDR), que a su vez actua sobre loselementos de respuesta a la vitamina D (VDRE) en el promotor de los genes diana,modificando su expresion. En las ultimas decadas, se ha demostrado que el VDR estapresente no solo en las dianas clasicas de la vitamina D, como los huesos, los rinones y elintestino, sino tambien en muchos otros tejidos, como los musculos esqueleticos, lisos, ycardiacos, y en el cerebro, la piel y el higado. Ademas del control de la homeostasis mineral,la vitamina D ejerce acciones pleiotropicos en diferentes tipos celulares, influyendo enprocesos fisiologicos importantes tales como la proliferacion y diferenciacion celular, larespuesta inmune, asi como diferentes condiciones patologicas como el cancer, lasenfermedades cardiovasculares, metabolicas y autoinmunes. Ademas, junto con sus efectosendocrinos, la vitamina D tiene papeles autocrinas/paracrinas importantes. En las celulas demusculo liso vascular (CMLV), la vitamina D regula la proliferacion y la calcificacion. Ambosprocesos, junto con la senescencia de las CMLV surgen durante el proceso aterosclerotico.Para poder dividirse, las CMLV necesitan la energia del ATP producido por las mitocondrias.Las alteraciones en la funcion mitocondrial estan relacionadas con una mayor produccion deradicales libres. En la pared arterial, la angiotensina II (Ang II) actua como un potentemediador de estres oxidativo, provocando senescencia prematura inducida por estres (SIPS).Los niveles de Ang II son controlados por la renina, cuya expresion genica se regula por lavitamina D. Por lo tanto, un defecto en la senalizacion de la vitamina D puede conducir a unaumento en los niveles de Ang II y sus efectos adversos en la pared arterial.Cuando se cultivaron CMLV, obtenidas de ratones knockout para VDR (VDRKO) seencontro un aumento en la produccion de Ang II en el medio de cultivo de estas celulas,comparando con el tipo salvaje (WT), lo que estaba de acuerdo con la mayor activacion de lasistema renina-angiotensina a nivel sistemico, que fue encontrada en los ratones mutantesde VDR. Por otra parte, una disminucion en la tasa de proliferacion de las VDRKO CMLV fueencontrada in vitro e in vivo. Este descenso era en paralelo a un aumento en el volumencelular. En estado de reposo, las celulas VDRKO presentaron un aumento significativo en laexpresion de p57Kip2 junto con niveles elevados de p19Arf, p21Cip1 y p27Kip1, y menoresniveles de pRb fosforilada y ciclinas D y E, asi previniendo su proliferacion. Ademas, lascelulas VDRKO mostraron un aumento en la expresion de la catepsina D, una enzima conactividad parecida a la del renina, y del receptor de Ang II tipo 1. Ademas, la produccion delanion superoxido fue mayor en las celulas mutantes, y fue inhibida tanto con losartan comocon DPI. Por otra parte, las celulas VDRKO presentaron una disminucion significativa en laexpresion de la enzima antioxidante mitocondrial superoxido dismutasa de manganeso(SOD2) y la oxido nitrico sintetasa inducible, que produce la molecula vasodilatadora NO. Porrespirometria de alta resolucion fue determinado que las mitocondrias de las CMLV VDRKOfueron menos eficientes que podria explicar el menor contenido de ATP en estas celulas.Todos estos factores se relacionaron con el fenotipo senescente, presentado por alrededor de20% de las CMLV que carecian VDR en cultivo.En conclusion, la ausencia de senalizacion por VDR en CMLV lleva a SIPS debido alaumento en la produccion local de Ang II, con el consiguiente aumento de los radicaleslibres, producidos por la activacion de la NADPH oxidasa, lo que sugiere un posible papel delsistema de la vitamina D en enfermedades vasculares, que muestran una hiperproliferacionde las CMLV. Vitamin D has long been known for its important role in regulating the levelsof calcium and phosphorus, and in mineralization of bone. The biological effects ofthe hormonally active form of vitamin D (1,25(OH)2D3, or calcitriol) are mediatedby the binding to the vitamin D receptor (VDR) which in turn acts over specificresponsive elements (VDRE) in the promoter region of the vitamin D - target genes,modifying their expression. In the last decades, it has been shown that VDR ispresent not only in the classical vitamin D targets such as bone, kidney, andintestine, but also in many other tissues, like skeletal, smooth, and heart muscles,and in brain, skin, and liver. In addition to the control of the mineral homeostasis,vitamin D exerts pleiotropic actions in a variety of cell types, influencing importantphysiological processes such as cellular proliferation and differentiation, theimmune response as well as different pathological conditions like cancer,cardiovascular, metabolic and autoimmune diseases. Moreover, together with itsendocrine effects, vitamin D has important autocrine/paracrine roles. In vascularsmooth muscle cells (VSMC), vitamin D regulates proliferation and calcification.Both processes, together with VSMC senescence occur during the atheroscleroticprocess. To be able to divide, VSMC need the energy of ATP produced bymitochondria. Alterations in the mitochondrial function are related to increasedproduction of free radicals. In the artery wall, angiotensin II (Ang II) serves as apotent mediator of oxidative stress, provoking stress-induced prematuresenescence (SIPS). Ang II levels are controlled by renin, which gene expression isregulated by vitamin D. Thus, a defect of vitamin D signalling could lead to anincrease in Ang II levels and its adverse effects in the artery wall.When we cultured VSMC, obtained from VDR knockout (VDRKO) mice wefound an increment in the production of Ang II in the culture medium of these cellsin comparison with the wild type (WT), which was in accordance with the increasedactivation of the renin-angiotensin system at systemic level, found in the VDRmutant mice. Moreover, a decrease in the proliferation rates of VDRKO VSMC wasfound in vitro and in vivo. This decrease was in parallel to an increase in the cellvolume. In quiescent state, VDRKO cells presented significantly increasedexpression of p57Kip2 together with elevated levels of p19Arf, p21Cip1 and p27Kip1, andlower levels of phosphorilated pRb and cyclins D and E, thus preventing theirproliferation. Furthermore, VDRKO cells showed an increase in the expression ofcathepsin D, an enzyme with renin-like activity, and of the Ang II receptor type 1.Also, superoxide anion production was higher in the mutant cells, and was inhibitedwith both, losartan and DPI. Moreover, the VDR ablated cells presented a significantdecrease in the expression of the mitochondrial antioxidant enzyme manganesesuperoxide dismutase (SOD2) and the inducible nitric oxide synthase, whichproduces the vasodilatator molecule NO. By high-resolution respirometry we foundthat the mitochondria of VDRKO VSMC were less efficient which could explain thelower content of ATP in these cells. All of these findings were associated with thesenescent phenotype, presented by around 20% of the VSMC lacking VDR inculture.In conclusion, the absence of VDR signalling in VSMC leads to SIPS due to theincreased local production of Ang II, with a subsequent increase in free radicals,produced by the activation of the NADPH oxidase, which suggests a possible role ofthe vitamin D system in vascular conditions which show hyperproliferation of VSMC
KINETIC STUDY OF THE ENZYME CONVERSION OF STEAM EXPLODED PAULOWNIA TOMENTOSA TO GLUCOSE
Paulownia Tomentosa was pretreated by steam explosion. The cellulase complex NS 50013 and the β-glucosidase NS 50010 of Novozymes AS were used for the enzymatic conversion of cellulose to glucose. The kinetics of enzyme conversion was studied using the exponential kinetic equation valid for processes taking place at uniformly inhomogeneous surfaces. The kinetic coefficient of inhomogeneity accounts for the energy and entropy inhomogeneity of the system and depends on the temperature. It was established that both the activation energy and the pre-exponential factor increase simultaneously with increasing of conversion degree. A compensation effect between pre-exponential factor and activation energy was observed. The energetic hindrances established cannot be completely compensated by the positive effect of the pre-exponential factor increase. Hence, the activation energy has a determining influence on how quickly the rate of hydrolysis decreases
Tu1984 Chemically Defined Diet Alters the Protective Properties of Fructo-Oligosaccharides and Isomalto-Oligosaccharides in a Rodent Model of Colitis
1091a Beta-Fructans Reduce Inflammation in Mild to Moderate Ulcerative Colitis Through Specific Microbiota Changes Associated With Improved Butyrate Formation and MUC2 Expression
T2042 Degree of Polymerisation of Prebiotic Beta-Fructans Affects Microflora Changes and Colitis Reduction in HLA-B27 Transgenic Rats
Chemically Defined Diet Alters the Protective Properties of Fructo-Oligosaccharides and Isomalto-Oligosaccharides in HLA-B27 Transgenic Rats
<div><p>Non-digestible oligosaccharides (NDO) were shown to reduce inflammation in experimental colitis, but it remains unclear whether microbiota changes mediate their colitis-modulating effects. This study assessed intestinal microbiota and intestinal inflammation after feeding chemically defined AIN-76A or rat chow diets, with or without supplementation with 8 g/kg body weight of fructo-oligosaccharides (FOS) or isomalto-oligosaccharides (IMO). The study used HLA-B27 transgenic rats, a validated model of inflammatory bowel disease (IBD), in a factorial design with 6 treatment groups. Intestinal inflammation and intestinal microbiota were analysed after 12 weeks of treatment. FOS and IMO reduced colitis in animals fed rat chow, but exhibited no anti-inflammatory effect when added to AIN-76A diets. Both NDO induced specific but divergent microbiota changes. Bifidobacteria and <i>Enterobacteriaceae</i> were stimulated by FOS, whereas copy numbers of <i>Clostridium</i> cluster IV were decreased. In addition, higher concentrations of total short-chain fatty acids (SCFA) were observed in cecal contents of rats on rat chow compared to the chemically defined diet. AIN-76A increased the relative proportions of propionate, iso-butyrate, valerate and iso-valerate irrespective of the oligosaccharide treatment. The SCFA composition, particularly the relative concentration of iso-butyrate, valerate and iso-valerate, was associated (P≤0.004 and r≥0.4) with increased colitis and IL-1 β concentration of the cecal mucosa. This study demonstrated that the protective effects of fibres on colitis development depend on the diet. Although diets modified specific cecal microbiota, our study indicates that these changes were not associated with colitis reduction. Intestinal inflammation was positively correlated to protein fermentation and negatively correlated with carbohydrate fermentation in the large intestine.</p></div
Quantification of predominant bacterial groups and bacterial genes in cecal contents of HLA-B27 transgenic rats on AIN-76A diet or rat chow diet at the end of the experimental treatment period (16 weeks of age).
<p>*Results are represented as means±SEM and depict the percent of the respective bacterial group/gene related to total bacteria. Values obtained with the same primer pair that do not share a common superscript are significantly different (<i>P</i><0.05, Bonferroni adjustment).</p><p>**ND, not detected.</p><p>Quantification of predominant bacterial groups and bacterial genes in cecal contents of HLA-B27 transgenic rats on AIN-76A diet or rat chow diet at the end of the experimental treatment period (16 weeks of age).</p