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Role of ALADIN for Oxidative Stress Response and Microsomal Steroidogenesis in Human Adrenocortical CellsJühlen, Ramona 12 November 2015 (has links)
Autosomal recessive triple A syndrome is caused by mutations in the AAAS gene encoding the protein ALADIN. The disorder manifests with the triad of adrenocorticotropin-resistant adrenal insufficiency, achalasia of the stomach cardia and impaired tear production (alacrima) in combination with progressive neurological impairment of the central, peripheral and autonomic nervous systems. ALADIN is part of the nuclear pore complex acting as a scaffold nucleoporin. In this work the role of ALADIN in the human adrenocortical tumour cell line NCI-H295R1 was investigated. These cells were engineered to either over-express or down-regulate AAAS by inducible stable transfection. Alterations in steroidogenic gene expression and functional consequences were determined. In addition, the role of ALADIN on cell viability and oxidative stress response was analysed. Using both the human adrenal NCI-H295R1-TR AAAS knock-down and over-expression models the potential impairment of the nuclear import of aprataxin, DNA ligase 1 and ferritin heavy chain 1 was investigated. For this YFP-specific vectors transiently transfected into the cell lines were employed.
The findings indicate that AAAS knock-down induces a down-regulation of genes coding for type II microsomal cytochrome P450 hydroxylases CYP17A1 and CYP21A2 and their electron donor enzyme cytochrome P450 oxidoreductase, thereby decreasing biosynthesis of precursor metabolites required for glucocorticoid and androgen production. Furthermore I demonstrate that ALADIN deficiency leads to increased susceptibility to oxidative stress and alteration in redox homeostasis after paraquat treatment. Finally, I show significantly impaired nuclear import of DNA ligase 1, aprataxin and ferritin heavy chain 1 in ALADIN knock-down cells. I conclude that down-regulating ALADIN results in decreased oxidative stress response leading to alteration in steroidogenesis, highlighting the knock-down cell model as an important in vitro tool for studying the adrenal phenotype in triple A syndrome.
In an approach to identify new interaction partners of ALADIN, co-immunoprecipitation followed by proteome analyses using mass spectrometry was conducted in a GFP-ALADIN over-expression model using the human adrenocortical tumor cell line NCI-H295R. These results were verified in co-immunoprecipitation assays of endogenous ALADIN using NCI-H295R wild-type cells. The results suggest a possible interaction between ALADIN and microsomal flavoprotein cytochrome P450 oxidoreductase and progesterone receptor membrane compartment 2. Co-localisation analyses of these findings were done using immunofluorescence. The data are suggestive for an involvement of ALADIN in the export of nuclear-encoded mitochondrial proteins.
Regulation of adrenocortical steroidogenesis is complex and there is increasing evidence that oxidative stress due to ROS accumulation and mitochondria are significantly involved. Furthermore, there may be an important cross-talk between functional organelles comprising nucleus, ER and mitochondria which presumably involves lipid metabolism. The goal of this work was to elucidate the function of ALADIN for the cellular oxidative stress response and its possible consequences for adrenocortical steroidogenesis in triple A syndrome patients. / Mutationen im AAAS Gen verursachen die autosomal rezessive Krankheit Triple-A-Syndrom. AAAS kodiert das Nukleoporin ALADIN, welches Bestandteil des nukleären Porenkomplexes ist. Phänotypische Charakteristika des Triple-A-Syndroms sind Nebennierenrinden-Insuffizienz, Achalasie des unteren Speiseröhrenschließmuskels und eine fehlende Tränenproduktion (Alakrimie). Diese Symptome sind kombiniert mit progredienten neurologischen Störungen des zentralen, peripheren und autonomen Nervensystems. In dieser Arbeit wurde die Rolle von ALADIN in der humanen Karzinom-Zelllinie NCI-H295R1 untersucht. Diese Nebennierenrinden-Zellen wurden stabil transfiziert und mit einem induzierbaren Expressionssystem modifiziert, so dass sie AAAS entweder überexprimierten oder herunterregulierten. In NCI-H295R1-Zellen wurden Veränderungen der Genexpression von Enzymen der Steroidogenese und funktionelle Konsequenzen der Überexpression oder Herunterregulation von ALADIN gemessen. Des Weiteren wurde die Rolle von ALADIN auf die Zellviabilität und die Redox-Homöostase analysiert. ALADIN überexprimierende und herunterregulierte Zellen wurden verwendet, um die potentielle Behinderung des nukleären Imports von Proteinen zu untersuchen, welche den Zellkern gegen oxidativen Stress schützen (z.B. Aprataxin, DNA-Ligase 1 und Ferritin Heavy Chain 1). Dazu wurden YFP-spezifische Vektoren transient in diese Zellen gebracht.
Mit den Ergebnissen dieser Arbeit wurde gezeigt, dass die Herunterregulation von AAAS eine Verminderung der Genexpression von CYP17A1 und CYP21A2 und deren Elektronendonor Cytochrom P450 Oxidoreduktase bewirken. Die Biosynthese der Vorläufermetabolite von Kortisol und Aldosteron ist in diesen Zellen ebenfalls vermindert. Des Weiteren zeigen die ALADIN-defizienten NCIH295R1-Zellen eine erhöhte Sensitivität gegenüber oxidativem Stress und eine veränderte Redox-Homöostase nach der Behandlung mit Paraquat. Darüber hinaus konnte in dieser Studie auch gezeigt werden, dass herunterregulierte ALADIN NCI-H295R1-Zellen einen verminderten Zellkernimport von Aprataxin, DNA-Ligase 1 und Ferritin heavy chain 1 besitzen. Aus diesen Ergebnissen kann geschlussfolgert werden, dass ALADIN-defiziente Nebennierenzellen eine verminderte Stressantwort auf oxidativen Stress besitzen; dies führt schlussendlich zu einer veränderten Steroidogenese. Das beschriebene ALADIN knock-down Modell in NCI-H295R1-Zellen ist ein wichtiges in vitro Werkzeug, um die Pathogenese der Nebennierenveränderungen im Triple-A-Syndrom zu erforschen.
Neue Interaktionspartner von ALADIN wurden mit Hilfe von Co-Immunpräzipitation gefolgt von Proteom-Analysen durch Massenspektrometrie in einem GFP-ALADIN Überexpressionsmodell in NCI-H295R charakterisiert. Die Ergebnisse wurden durch Experimente auf endogenem Niveau in NCI-H295R-Wildtypzellen verifiziert. Mit diesen Daten wird in dieser Arbeit erstmals eine Interaktion zwischen ALADIN und dem Flavoprotein Cytochrom P450 Oxidoreduktase und Progesterone Receptor Membrane Compartment 2 nachgewiesen. Diese Ergebnisse wurden mit Co-Lokalisierungsanalysen durch Immunfluoreszenzfärbung von ALADIN und Cytochrome P450 Oxidoreduktase ergänzt. Außerdem gibt die Arbeit Hinweise darauf, dass ALADIN als Nukleoporin an dem nuklearen Export mitochondrialer Vorläuferproteine beteiligt ist.
Die Regulation der Steroidogenese in der Nebennierenrinde ist komplex und es existieren zahlreiche Hinweise darauf, dass oxidativer Stress aufgrund der Ansammlung reaktiver Sauerstoffradikale und. dass die Mitochondrien involviert sind. Außerdem ist ein funktionelles Zusammenspiel verschiedener Organellen, darunter Nukleus, ER und Mitochondrien, von großer Bedeutung. Das Ziel dieser Arbeit war die Identifizierung der Funktion von ALADIN in der zellulären oxidativen Stressantwort und die möglichen Konsequenzen für die Steroidogenese in der Nebennierenrinden in Triple-A-Syndrom-Patienten. Read more
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Effekten av två olika kompressionslindor vid läkning av venösa bensårAljaderi, Jacob, Nakos, Georgios January 2021 (has links)
SAMMANFATTNING Bakgrund: Venösa bensår är ett globalt vanligt förekommande fenomen, 1–2 % av jordens befolkning anses vara drabbade. Bensår skapar stort lidande för patientens fysiska och psykiska hälsa. Två vanliga förekommande problem är smärta och isolering. Det finns flera metoder för att läka venösa bensår där flerlagers-kompressionslinda anses vara en av det bästa metoderna. Att läka bensår skulle kunna minska patientlidandet. Syfte: Att sammanställa och jämföra läkningseffekten av två- och fyra-lagerskompressionslindning hos patienter med venösa bensår. Metod: En deskriptiv design med litteraturöversikt användes som metod där tio vetenskapliga kvantitativa originalartiklar inkluderades. Artikelsökning gjordes i databaserna PubMed och CINAHL. Resultat: Litteraturöversikten kunde inte påvisa en skillnad mellan 2LB- och 4LB-kompressiongrupperna för förbättrad och fullständig läkningsförmåga. Båda lindorna bekräftades ha en sårläkande effekt. Effekten av kompressionslindorna gav en mer påskyndad sårläkning, än hos patienter utan kompressionsbehandling. Majoriteten av de inkluderade studierna visade på ett liknande resultat i fullständig procentuell läkning mellan två-lagerkompressionslindning (2LB) och fyra-lagerkompressionslindning (4LB). Slutsats: Litteraturöversikten visar att kompressionsbehandling med 2LB och 4LB har en likvärdig och god sårläkande effekt för patienter. Både 2LB och 4LB är mer gynnsam för sårläkning och välmående än utan kompressionsbehandling för patienter som lever med venösa bensår. / ABSTRACT Background: Venous leg ulcers is a globally common phenomenon, 1-2 % of the world’s population is believed to be affected. Leg ulcers causes great suffering for the patient's physical and mental health. Two common complications are pain and isolation. There are several methods to heal venous leg ulcers, multilayer-compression-therapy is considered one of the best methods. Healing leg ulcers could reduce patient suffering. Purpose: To compile and compare the healing effects of two- and four-layer compression therapy in patients with venous leg ulcers. Method: A descriptive design with a literature review as method, with ten scientific quantitative original articles were included. Article searches was done in databases PubMed and CINAHL. Results: The results did not show a difference between the 2LB and 4LB-groups regarding complete and improved healing. However, both methods had a healing effect. The bandages were more effective in accelerating healing in patients, than in patients without compression therapy. Most of the included studies showed a similar result in the percentage of complete healing effect between the two-layer compression therapy (2LB) and four-layer compression therapy (4LB). Conclusion: This literature review demonstrated that compression therapy with 2LB and 4LB has an equally as well as good healing effect for patients. Both 2LB and 4LB are significantly more beneficial for wound healing and well-being than without compression therapy for patients living with venous leg ulcers. Read more
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Der Einfluss von Noradrenalin auf Gap Junction KanäleGlawe, Inken 27 September 2011 (has links)
Gap Junction Kanäle sind wesentlich für die interzelluläre Kommunikation im Herzen. Die wichtigsten kardialen Gap Junction Proteine sind Connexin 43, Connexin 40 und in frühen Entwicklungsstadien Connexin 45. Da Katecholamine eine wichtige Rolle in der kardialen Physiologie bzw. Pathophysiologie spielen, sollte geklärt werden, ob Katecholamine die Expression von Connexin 40 und Connexin 43 beeinflussen.
Es wurden neonatale Rattenkardiomyozyten in Zellkultur 24 Stunden mit aufsteigenden Noradrenalinkonzentrationen (1-10000 nM) (physiologischer Agonist für α-und β-Adrenozeptoren) inkubiert. Hier zeigte sich ein signifikanter Anstieg der Connexin 43 Expression, während die Connexin 40 Expression nicht beeinflußt wurde.
Um zu zeigen über welchen Adrenozeptor (α oder β) die Hochregulation von Cx 43 durch Noradrenalin erfolgt, wurden die Zellkulturen in zwei weiteren Versuchsreihen zusätzlich mit einem β-Blocker (Propranolol 100µM) bzw. einem α- Blocker (Prazosin 10 µM) über 24 Std. inkubiert. Hier zeigte sich eine deutliche Inhibierung des Noradrenalineffektes durch die Blockade der α-Rezeptoren durch Prazosin.
Eine Blockade der β-Rezeptoren hatte keinen inhibitorischen Effekt auf die Hochregulation der Expression von Cx 43 durch Noradrenalin. Es kam hier sogar zu einer verstärkten Expression verglichen mit der Cx 43 Expression unter Noradrenalin ohne Rezeptorblockade.
Desweiteren wurde überprüft, ob es auch unter der Behandlung von Sprague– Dawley-Ratten mit einem β-Mimetikum (Isoprenalin) bzw. einem α-Mimetikum (Phenylephrin) zu einer Veränderung der Connexinexpression kommt. Die Western Blot Analysen ergaben hierbei wieder einen α-Rezeptoren vermittelten Effekt, indem es zu einem wesentlichen Konzentrationsanstieg von Connexin 43 unter der Behandlung mit Phenylephrin kam. Read more
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A systemic Review: Are Outcomes of Aortic Valve Repair ‘A Beneficial alternative’ for patients with Aortic Valve Insufficiency?Malik, Samreen Mohammad January 2020 (has links)
IntroductionThe young adult patients with aortic valve insufficiency undergo aortic valve replacement (AVR) and are forced to take anticoagulation medications for the rest of life due to prosthetic valve. This leads to many post-operative complications and drastic outcomes. Whereas, the in-vogue alternative of aortic valve repair (AVr) is available and a lot more beneficial as well.Especially considering the surgeon’s skills for selected repair procedure, selectively chosen patient with mild to moderate grades of aortic valve insufficiency and no significant comorbidities present for at least five (5) years or longer time. AimThe aim of this study was to affirm ‘if all kind of outcomes of aortic valve repair are beneficial alternative to aortic valve replacement (AVR) for the patients suffering from aortic valve insufficiency for at least five (5) years or longer time. Material and MethodsInternet search using standard key words of ‘Aortic Valve Repair and Outcomes’ was used to find both white literature (officially published literature) and grey literature (unpublished or ongoing study/literature) with human, adult, English language and studies published after January 1st 2007 as limitations. Inclusion criteria was adult patients with aortic insufficiency with aortic valve repair as intervention with outcomes at least greater than five (5) years were considered. All the data was extracted using Microsoft excel for windows and was analyzed using GraphPad Prisma. Results20 studies comprising of 5369 patients were included in this systemic review, which included 2 randomized control trails, 7 clinical prospective studies, 8 retrospective studies and 3 observational studies. ConclusionThis study suggests that aortic valve repair is a beneficial alternative available for younger adults suffering from aortic valve insufficiency in longer time. Read more
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Venous haemodynamic and cerebrospinal fluid anomalies associated with multiple sclerosisBeggs, Clive B. January 2014 (has links)
This critical synopsis of prior work by Clive Beggs is submitted in support of a PhD
by published work. The work focuses on venous and cerebrospinal fluid (CSF)
anomalies associated with multiple sclerosis (MS) and other neurological diseases.
MS is characterized by focal inflammatory lesions, which are often venocentric.
Recently a vascular syndrome, chronic cerebrospinal venous insufficiency (CCSVI)
has been linked with MS. This syndrome, which is characterized by constricted
cerebral venous outflow, has become mired in controversy, with various studies
producing conflicting findings, with the result that the science associated with
CCSVI has become obscured.
Clive Beggs work seeks to bring clarity to the debate surrounding CCSVI by
characterizing physiological changes associated with constricted cerebral venous
outflow. The work submitted here involves collaborative studies with Robert
Zivadinov (University of Buffalo), Paolo Zamboni (University of Ferrara), and Chih-
Ping Chung (National Yang Ming University of Medicine). The key findings of these
studies are: (i) MS patients, diagnosed with CCSVI, exhibit greatly increased
hydraulic resistance of the cerebral venous drainage system; (ii) MS patients
experience loss of the small cerebral veins; (iii) MS patients exhibit reduced CSF
bulk flow, consistent with mild venous hypertension; (iv) MS patients exhibit
increased CSF pulsatility in the Aqueduct of Sylvius, which appears to be linked
with mild venous hypertension associated with CCSVI; and (v) jugular venous reflux
is associated with white matter and parenchymal volumetric changes in Alzheimer’s
patients. Collectively, these findings suggest that extracranial venous anomalies are
associated with changes in the intracranial physiology. Read more
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High-Sensitivity Cardiac Troponin T in Patients with Severe Chronic Kidney Disease and Suspected Acute Coronary SyndromeAlushi, Brunilda, Jost-Brinkmann, Fabian, Kastrati, Adnan, Cassese, Salvatore, Fusaro, Massimiliano, Stangl, Karl, Landmesser, Ulf, Thiele, Holger, Lauten, Alexander 04 May 2023 (has links)
(1) Background: Patients with severe chronic kidney disease (CKD G4–G5) often have chronically elevated high-sensitivity cardiac troponin T (hs-cTnT) values above the 99th percentile of the upper reference limit. In these patients, optimal cutoff levels for diagnosing non-ST-elevation acute coronary syndrome (NSTE-ACS) requiring revascularization remain undefined. (2) Methods: Of 11,912 patients undergoing coronary angiography from 2012 to 2017 for suspected NSTE-ACS, 325 (3%) had severe CKD. Of these, 290 with available serial hs-cTnT measurements were included, and 300 matched patients with normal renal function were selected as a control cohort. (3) Results: In the CKD cohort, 222 patients (76%) had NSTE-ACS with indication for coronary revascularization. Diagnostic performance was high at presentation and similar to that of the control population (AUC, 95% CI: 0.81, 0.75–0.87 versus 0.85, 0.80–0.89, p = 0.68), and the ROC-derived cutoff value was 4 times higher compared to the conventional 99th percentile. Combining the ROC-derived cutoff levels for hs-cTnT at presentation and absolute 3 h changes, sensitivity increased to 98%, and PPV and NPV improved up to 93% and 86%, respectively. (4) Conclusions: In patients with severe CKD and suspected ACS, the diagnostic accuracy of hs-cTnT for the diagnosis of NSTE-ACS requiring revascularization is improved by using higher assay-specific cutoff levels combined with early absolute changes. Read more
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Mechanisms of Inverted formin 2-mediated intracellular trafficking, invasion, and placentation in mouse and human pregnancyLamm, Katherine Young Bezold 07 June 2018 (has links)
No description available.
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The Collaborative Assessment of Neurocognition and Vision in Adolescents with Sports-related Concussion - The CANVAS Concussion StudyPeiffer, Adam J. 14 August 2018 (has links)
No description available.
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Livet med venösa bensår : En litteraturstudie / Life with venous leg ulcers : A literature reviewGostovic, Maja, Grube, Rebecca January 2022 (has links)
Gostovic, M & Grube, R. Livet med venösa bensår. En litteraturstudie. Examensarbete i omvårdnad 15 högskolepoäng. Malmö Universitet: Fakulteten för Hälsa och Samhälle, Institutionen för Vårdvetenskap, 2022. Bakgrund: Venösa bensår beror på venös insufficiens som är en kronisk sjukdom som orsakar cirkulatorisk svikt i de nedre extremiteterna och drabbar främst den äldre befolkningen. De venösa bensåren uppkommer ofta på grund av trombos, yttre trauma, fysisk inaktivitet eller hereditet. Det är vanligt med samsjuklighet vid venös insufficiens. Behandlingen består främst av omläggning och livslång kompressionsbehandling. Syfte: Syftet med litteraturstudien var att undersöka patienters upplevelser av att leva med venösa bensår. Metod: En litteraturstudie som är baserad på resultat från 13 empiriska studier med kvalitativ ansats från Cinahl, PubMed och PsycInfo. Studierna har granskats med hjälp av Kvalitetsgranskningsmall för studier med kvalitativ forskningsmetodik och de inkluderade studierna har bedömts vara av hög samt medelhög kvalitet. De inkluderade studiernas resultat analyserades med hjälp av integrerad sammanställning av kvalitativ forskning inspirerad av metasyntes. Resultat: Sex teman identifierades: Egenvårdens betydelse för välbefinnandet, Svårigheter i egenvården, Vården som en del av vardagen, Upplevelsen av smärta, Upplevd självbild och skam samt Social och psykisk påverkan. Konklusion: Litteraturstudien gav en ökad förståelse för vad det innebär att leva med venösa bensår och gav en insikt i vilka kunskapsluckor som vården behöver fylla för att kunna förse patienterna med en adekvat omvårdnad. / Gostovic, M & Grube, R. Life with venous leg ulcers. A Literature Review. Degree project in nursing 15 credit points. Malmö University: Faculty of Health and Society, Department of Care Science, 2022. Background: Venous leg ulcers is caused by venous insufficiency which is a chronic disease caused by circulatory deficiency in the lower extremities and affects primarily the elderly population. The venous leg ulcers most commonly originates from thrombosis, external trauma, physical inactivity or heredity. Comorbidity is common among the patients with venous leg ulcers. The treatment plan primarily consists of wound dressing and lifelong compression treatment. Aim: The aim of the study was to investigate the patients’ experiences of living with venous leg ulcers. Method: A literature review based on results from 13 empirical studies with qualitative design from Cinahl, PubMed and PsycInfo. The studies have been reviewed by using a review template intended for qualitative studies and the included studies were valued as high and medium high quality. The included studies results were analyzed with the help of an integrated compilation of qualitative research inspired by meta synthesis. Results: Six themes were identified: Self-care had an impact of the well-being, Health care as a part of the daily life, The experience of pain, Perceived self-image and shame and Social and psychological influence. Conclusion: The literature review increased the understanding of what it’s like to live with venous leg ulcers and gave an insight into which knowledge-gaps the health care needs to fill to provide the patients with adequate care. Read more
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In vitro approach of dietary and host related factors affecting digestion of animal-origin foods under cystic fibrosis diseaseAsensio Grau, Andrea 02 September 2021 (has links)
Tesis por compendio / [ES] De entre las metodologías disponibles para estudiar la digestión de alimentos, los modelos de digestión in vitro se plantean como procedimientos válidos para este propósito. La digestión in vitro consiste en simular el proceso de digestión en el laboratorio, reproduciendo las condiciones fisiológicas en cuanto a composición de los fluidos digestivos (electrolitos y enzimas), pH, temperatura, fuerzas mecánicas y duración de las etapas oral, gástrica e intestinal.
Abordar el estudio de la digestión de nutrientes es de especial relevancia en patologías que cursan con alteraciones pancreáticas o hepáticas, asociadas a una digestión de lípidos comprometida en la etapa intestinal, debido a la disminución de secreción de pancreatina, bicarbonato y sales biliares. Este es el caso de la fibrosis quística con insuficiencia pancreática, y los pacientes que padecen esta afección deben seguir la terapia de sustitución de enzimas pancreáticas, que consiste en el suministro exógeno de pancreatina encapsulada. Sin embargo, la dosis de este suplemento debe ajustarse a las características de los alimentos y no se dispone de ningún método válido para tal fin. Para hacer frente a este reto, en el proyecto financiado con fondos europeos MyCyFAPP se ha logrado desarrollar un método para ajustar la dosis óptima de los suplementos enzimáticos utilizados en la terapia. La presente tesis doctoral se realizó en el marco de dicho proyecto.
Concretamente, esta tesis tiene como objetivo abordar el estudio de la digestión de lípidos en los alimentos de origen animal (carne y productos cárnicos, huevos, queso y pescado) en el contexto de la fibrosis quística. Para abordar este objetivo se aplicó un modelo de digestión in vitro estático con el fin de explorar el papel de las características inherentes a los alimentos (estructura de la matriz alimentaria como resultado del procesado) y los factores relacionados con el individuo (pH, concentración de sales biliares y concentración de pancreatina) como factores determinantes de la lipólisis en alimentos de origen animal.
A lo largo de los cuatro capítulos presentados, centrados en el huevo, la carne, el queso y el pescado, se presenta un diseño experimental común para estudiar la lipólisis, la proteólisis y la degradación de la matriz. En cada estudio, las diferentes técnicas de procesado aplicadas a los alimentos evaluados también permitieron evaluar el efecto de las propiedades inherentes a los alimentos en los resultados del estudio. Los resultados han contribuido al desarrollo de un nuevo método basado en la evidencia para optimizar la terapia de reemplazo de enzimas pancreáticas e informan a la comunidad científica sobre nuevos conocimientos en el comportamiento de diferentes alimentos sometidos al proceso de digestión. / [CA] De les metodologies disponibles per estudiar la digestió d'aliments, els models de digestió in vitro es plantegen com a procediments vàlids per a aquest propòsit. La digestió in vitro consisteix en simular el procés de digestió al laboratori, reproduint les condicions fisiològiques pel que fa a la composició dels fluids digestius (electròlits i enzims), pH, temperatura, forces mecàniques i durada de les etapes oral, gàstrica i intestinal. Abordar l'estudi de la digestió de nutrients és d'especial rellevància en patologies que cursen amb alteracions pancreàtiques o hepàtiques, associades a una digestió de lípids compromesa en l'etapa intestinal, a causa de la disminució de secreció de pancreatina, bicarbonat i sals biliars. Aquest és el cas de la fibrosi quística amb insuficiència pancreàtica. Els pacients que pateixen aquesta afecció han de seguir la teràpia de substitució d'enzims pancreàtics, que consisteix en el subministrament exogen de pancreatina encapsulada. No obstant això, la dosi d'aquest suplement ha d'ajustar-se a les característiques dels aliments i actualment no es disposa de cap mètode vàlid per a tal fi. Per enfrontar a aquest repte, en el projecte finançat amb fons europeus, MyCyFAPP, s'ha aconseguit desenvolupar un mètode per a ajustar la dosi òptima dels suplements enzimàtics utilitzats en la teràpia. La present tesi doctoral es va realitzar en el marc d'aquest projecte.
Concretament, aquesta tesi té com a objectiu abordar l'estudi de la digestió de lípids en els aliments d'origen animal (ous, carn i productes carnis, formatge i peix) en el context de la fibrosi quística. Per a abordar aquest objectiu es va aplicar un model de digestió in vitro estàtic amb la finalitat d'explorar el paper de les característiques inherents als aliments (estructura de la matriu alimentària com a resultat del processament) i els factors relacionats amb l'individu (pH, concentració de sals biliars i concentració de pancreatina) com a factors determinants de la lipòlisi en aliments d'origen animal.
Als quatre capítols presentats, centrats en l'ou, carn, formatge i peix, es presenta un disseny experimental comú per a estudiar la lipòlisi, la proteòlisi i la degradació de la matriu. En cada estudi, les diferents tècniques de processament aplicades als aliments avaluats també van permetre avaluar l'efecte de les propietats inherents als aliments en els resultats de l'estudi. Els resultats han contribuït al desenvolupament d'un nou mètode basat en l'evidència per a optimitzar la teràpia de substitució d'enzims pancreàtics i informen la comunitat científica sobre nous coneixements en el comportament de diferents aliments sotmesos al procés de digestió. / [EN] Among the available methodologies to study food digestion, in vitro digestion models have raised as a valid procedure. In vitro digestion consists of simulating the digestion process in the laboratory, by reproducing the physiological conditions in terms of digestive fluids composition (electrolytes and enzymes), pH, temperature, mechanical forces and duration of the oral, gastric and intestinal stages.
Addressing the study of nutrient digestion is of special relevance in pathologies coursing with pancreatic or hepatic alterations, which are associated with compromised intestinal lipid digestion due to reduced secretion of pancreatin, bicarbonate and bile salts. This is the case of Cystic Fibrosis along with pancreatic insufficiency, and the patients suffering this condition have to follow pancreatic enzyme replacement therapy, the exogenous supply of encapsulated pancreatin. However, the dose of this supplement should be adjusted to the specific characteristics of foods, and no valid method was available for such purpose. To tackle this challenge, the EU-funded project MyCyFAPP succeed to develop a method to adjust the optimal dose the enzyme supplements used in the therapy. The present doctoral thesis was conducted as a relevant part of this project.
Concretely, this thesis aims at addressing the study of lipid digestion in foods to generate new knowledge regarding nutrient digestion in animal origin dietary sources (egg, meat and meat products, cheese and fish) in the context of Cystic Fibrosis. To address this goal a static in vitro digestion model was applied. The role of inherent-to-food characteristics (resulting food matrix structure from processing) and host related factors (pH and bile salts concentration and pancreatin concentration) were explored as determinants of lipolysis in animal-origin foods.
Along the four chapters presented, focused on egg, meat, cheese and fish, a common experimental design was applied to study lipolysis, proteolysis and matrix degradation. In each study, different processing techniques applied to the assessed foods allowed for evaluating the effect of inherent-to-food properties on the study outcomes as well. The results have contributed to the development of a new evidence-based method to optimise pancreatic enzyme replacement therapy, and inform the scientific community about new insights on the behaviour of different foods undertaking the digestion process. / Authors of this paper acknowledge the European Union and the Horizon 2020
Research and Innovation Framework Programme (PHC-26-2014 call Self-management
of health and disease: citizen engagement and mHealth) for fully funding this research
in the context of MyCyFAPP Project, under grant agreement number 643806.
The authors would like to thank the Conselleria de Educació i Investigació de la
Generalitat Valenciana and also the European Union (“El Fondo Social Europeo (FSE)
invierte en tu futuro”) for the PhD scholarship given to Andrea Asensio Grau
(ACIF/2017/008). This study was developed thanks to the equipment funded with the
support from the Generalitat Valenciana IDIFEDER/2018/041 (PO FEDER Comunitat
Valenciana 2014-2020). Finally, we thank
Antonio Martínez Cañada, from the Data Science and Biostatistics Unit of Instituto de
Investigación Sanitaria La Fe, and Arash Javanidejad for the English corrections. / Asensio Grau, A. (2021). In vitro approach of dietary and host related factors affecting digestion of animal-origin foods under cystic fibrosis disease [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/171512 / Compendio Read more
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