Paula Olaizola Rebe

Ms. Paula Olaizola Rebe

orcid

Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 March 2023 in Journal of Hepatology
Verified
Journal Article
Open access
ALAinhoa Lapitz
Ainhoa Lapitz
MAMikel Azkargorta
Mikel Azkargorta
PMPiotr Milkiewicz
Piotr Milkiewicz
PRPaula Olaizola Rebe
Paula Olaizola Rebe
EZEkaterina Zhuravleva
Ekaterina Zhuravleva
Jesús BañalesJesús Bañales
Jesús Bañales
Cholangiocarcinoma (CCA), heterogeneous biliary tumours with dismal prognosis, lacks accurate early diagnostic methods especially important for individuals at high-risk (i.e. those with primary sclerosing cholangitis [PSC]). Here, we searched for protein biomarkers in serum extracellular vesicles (EVs). EVs from patients with isolated PSC (n = 45), concomitant PSC-CCA (n = 44), PSC who developed CCA during follow-up (PSC to CCA; n = 25), CCAs from non-PSC aetiology (n = 56), and hepatocellular carcinoma (n = 34) and healthy individuals (n = 56) were characterised by mass spectrometry. Diagnostic biomarkers for PSC-CCA, non-PSC CCA, or CCAs regardless of aetiology (Pan-CCAs) were defined and validated by ELISA. Their expression was evaluated in CCA tumours at a single-cell level. Prognostic EV biomarkers for CCA were investigated. High-throughput proteomics of EVs identified diagnostic biomarkers for PSC-CCA, non-PSC CCA, or Pan-CCA, and for the differential diagnosis of intrahepatic CCA and hepatocellular carcinoma, which were cross-validated by ELISA using total serum. Machine learning-based algorithms disclosed CRP/FIBRINOGEN/FRIL for the diagnosis of PSC-CCA (local disease [LD]) vs. isolated PSC (AUC = 0.947; odds ratio [OR] =36.9) and, combined with carbohydrate antigen 19-9, overpowers carbohydrate antigen 19-9 alone. CRP/PIGR/VWF allowed the diagnosis of LD non-PSC CCAs vs. healthy individuals (AUC = 0.992; OR = 387.5). It is noteworthy that CRP/FRIL accurately diagnosed LD Pan-CCA (AUC = 0.941; OR = 89.4). Levels of CRP/FIBRINOGEN/FRIL/PIGR showed predictive capacity for CCA development in PSC before clinical evidence of malignancy. Multi-organ transcriptomic analysis revealed that serum EV biomarkers were mostly expressed in hepatobiliary tissues, and single-cell RNA sequencing and immunofluorescence analysis of CCA tumours showed their presence mainly in malignant cholangiocytes. Multivariable analysis unveiled EV prognostic biomarkers, with COMP/GNAI2/CFAI and ACTN1/MYCT1/PF4V associated negatively and positively with patients' survival, respectively. Serum EVs contain protein biomarkers for the prediction, early diagnosis, and prognostication of CCA that are detectable using total serum, representing a tumour cell-derived liquid biopsy tool for personalised medicine. The accuracy of current imaging tests and circulating tumour biomarkers for cholangiocarcinoma (CCA) diagnosis is far from satisfactory. Most CCAs are considered sporadic, although up to 20% of patients with primary sclerosing cholangitis (PSC) develop CCA during their lifetime, constituting a major cause of PSC-related death. This international study has proposed protein-based and aetiology-related logistic models with predictive, diagnostic, or prognostic capacities by combining two to four circulating protein biomarkers, moving a step forward into personalised medicine. These novel liquid biopsy tools may allow the (i) easy and non-invasive diagnosis of sporadic CCAs, (ii) identification of patients with PSC with higher risk for CCA development, (iii) establishment of cost-effective surveillance programmes for the early detection of CCA in high-risk populations (e.g. PSC), and (iv) prognostic stratification of patients with CCA, which, altogether, may increase the number of cases eligible for potentially curative options or to receive more successful treatments, decreasing CCA-related mortality.

3 March 2020 in Molecules
Verified
Journal Article
Open access
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Oihana GordobilOihana Gordobil
Oihana Gordobil
PRPaula Olaizola Rebe
Paula Olaizola Rebe
Jesús BañalesJesús Bañales
Jesús Bañales
Jalel LabidiJalel Labidi
Jalel Labidi
The growing concern about the environmental impact and human health risk related to the excessive use of synthetic ingredients in cosmetics and topical formulations calls for the exploration of safe and sustainable natural alternatives. Lignin-rich lignocellulosic industrial wastes such as hazelnut and walnut shells were used as a lignin polymer source. Agro-derived lignins were evaluated as a potential natural active ingredient for health care products. Aside from the structural characteristics of isolated lignins, which were identified by GPC, Py-GC–MS, and 2D HSQC NMR techniques, functional properties such as antioxidant power and UV absorption ability were investigated. The SPF values found for creams containing 5% of hazelnut and walnut lignin content were 6.9 and 4.5, respectively. Additionally, both lignin types presented appropriate protection against UVA radiation, highly interesting property to block the full ultraviolet spectrum. The biological activity of isolated lignins assessed at different concentrations (0.01–1 mg/mL) and different times (24, 48, and 72 h) on murine fibroblast cell line 3T3 suggested their suitability for cosmetic applications.

1 March 2022 in Nature Communications
Verified
Journal Article
Open access
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DUDiego Sáenz de Urturi
Diego Sáenz de Urturi
XBXabier Buqué
Xabier Buqué
BPBegoña Porteiro
Begoña Porteiro
CFCintia Folgueira
Cintia Folgueira
AMAlfonso Mora
Alfonso Mora
PAPatricia Aspichueta
Patricia Aspichueta
Altered methionine metabolism is associated with weight gain in obesity. The methionine adenosyltransferase (MAT), catalyzing the first reaction of the methionine cycle, plays an important role regulating lipid metabolism. However, its role in obesity, when a plethora of metabolic diseases occurs, is still unknown. By using antisense oligonucleotides (ASO) and genetic depletion of Mat1a, here, we demonstrate that Mat1a deficiency in diet-induce obese or genetically obese mice prevented and reversed obesity and obesity-associated insulin resistance and hepatosteatosis by increasing energy expenditure in a hepatocyte FGF21 dependent fashion. The increased NRF2-mediated FGF21 secretion induced by targeting Mat1a, mobilized plasma lipids towards the BAT to be catabolized, induced thermogenesis and reduced body weight, inhibiting hepatic de novo lipogenesis. The beneficial effects of Mat1a ASO were abolished following FGF21 depletion in hepatocytes. Thus, targeting Mat1a activates the liver-BAT axis by increasing NRF2-mediated FGF21 secretion, which prevents obesity, insulin resistance and hepatosteatosis.

1 April 2023 in Hepatology
Verified
Journal Article
Open access
FCFrancisco J. Caballero-Camino
Francisco J. Caballero-Camino
Cecilia MP RodrigugesCecilia MP Rodriguges
Cecilia MP Rodriguges
FWFredrik Wångsell
Fredrik Wångsell
AAAloña Agirre-Lizaso
Aloña Agirre-Lizaso
PRPaula Olaizola Rebe
Paula Olaizola Rebe
Jesús BañalesJesús Bañales
Jesús Bañales
Background and Aims: Cholestasis is characterized by intrahepatic accumulation of bile constituents, including bile acids (BAs), which promote liver damage. The apical sodium-dependent BA transporter (ASBT) plays an important role in BA reabsorption and signaling in ileum, bile ducts, and kidneys. Our aim was to investigate the pharmacokinetics and pharmacological activity of A3907, an oral and systemically available ASBT inhibitor in experimental mouse models of cholestasis. In addition, the tolerability, pharmacokinetics, and pharmacodynamics of A3907 were examined in healthy humans. Approach and Results: A3907 was a potent and selective ASBT inhibitor in vitro. In rodents, orally administered A3907 distributed to the ASBT-expressing organs, that is, ileum, liver, and kidneys, and dose dependently increased fecal BA excretion. A3907 improved biochemical, histological, and molecular markers of liver and bile duct injury in Mdr2 −/− mice and also had direct protective effects on rat cholangiocytes exposed to cytotoxic BA concentrations in vitro. In bile duct ligated mice, A3907 increased urinary BA elimination, reduced serum BA levels, and prevented body weight loss, while improving markers of liver injury. A3907 was well tolerated and demonstrated target engagement in healthy volunteers. Plasma exposure of A3907 in humans was within the range of systemic concentrations that achieved therapeutic efficacy in mouse. Conclusions: The systemic ASBT inhibitor A3907 improved experimental cholestatic disease by targeting ASBT function at the intestinal, liver, and kidney levels, resulting in marked clearance of circulating BAs and liver protection. A3907 is well tolerated in humans, supporting further clinical development for the treatment of cholestatic liver diseases.

13 May 2022 in Nature Reviews Gastroenterology & Hepatology
Verified
Journal Article
Closed access
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PRPaula Olaizola Rebe
Paula Olaizola Rebe
Cecilia MP RodrigugesCecilia MP Rodriguges
Cecilia MP Rodriguges
FCFrancisco J. Caballero-Camino
Francisco J. Caballero-Camino
LILaura Izquierdo-Sanchez
Laura Izquierdo-Sanchez
PAPatricia Aspichueta
Patricia Aspichueta
Jesús BañalesJesús Bañales
Jesús Bañales

1 February 2021 in Journal of Hepatology
Verified
Journal Article
Open access
PLPui Y. Lee-Law
Pui Y. Lee-Law
PRPaula Olaizola Rebe
Paula Olaizola Rebe
FCFrancisco J. Caballero-Camino
Francisco J. Caballero-Camino
LILaura Izquierdo-Sanchez
Laura Izquierdo-Sanchez
PRPedro M. Rodrigues
Pedro M. Rodrigues
Jesús BañalesJesús Bañales
Jesús Bañales
Polycystic liver diseases (PLDs) are genetic disorders characterized by progressive development of multiple fluid-filled biliary cysts. Most PLD-causative genes participate in protein biogenesis and/or transport. Post-translational modifications (PTMs) are implicated in protein stability, localization and activity, contributing to human pathobiology; however, their role in PLD is unknown. Herein, we aimed to unveil the role of protein SUMOylation in PLD and its potential therapeutic targeting. Levels and functional effects of SUMOylation, along with response to S-adenosylmethionine (SAMe, inhibitor of the SUMOylation enzyme UBC9) and/or short-hairpin RNAs (shRNAs) against UBE2I (UBC9), were evaluated in vitro, in vivo and/or in patients with PLD. SUMOylated proteins were determined by immunoprecipitation and proteomic analyses by mass spectrometry. Most SUMOylation-related genes were found overexpressed (mRNA) in polycystic human and rat liver tissue, as well as in cystic cholangiocytes in culture compared to controls. Increased SUMOylated protein levels were also observed in cystic human cholangiocytes in culture, which decreased after SAMe administration. Chronic treatment of polycystic (PCK: Pkdhl-mut) rats with SAMe halted hepatic cystogenesis and fibrosis, and reduced liver/body weight ratio and liver volume. In vitro, both SAMe and shRNA-mediated UBE2I knockdown increased apoptosis and reduced cell proliferation of cystic cholangiocytes. High-throughput proteomic analysis of SUM01-immunoprecipitated proteins in cystic cholangiocytes identified candidates involved in protein biogenesis, ciliogenesis and proteasome degradation. Accordingly, SAMe hampered proteasome hyperactivity in cystic cholangiocytes, leading to activation of the unfolded protein response and stress-related apoptosis. Cystic cholangiocytes exhibit increased SUMOylation of proteins involved in cell survival and proliferation, thus promoting hepatic cystogenesis. Inhibition of protein SUMOylation with SAMe halts PLD, representing a novel therapeutic strategy.