Uloga proteina SUFU u povezivanju Wnt i Hedgehog signalnoga puta u posteljica s intrauterinim zastojem u rastu

doctoral thesis

• Title (english): SUFU protein's function in connecting Wnt and Hedgehog signaling pathways in placentas with intrauterine growth restriction
• Author: Ida Marija Šola
• Mentor: Ljiljana Šerman (mentor)
• Mentor: Krunoslav Kuna (komentor)
• Committee member: Floriana Jakuš (predsjednik povjerenstva)
• Committee member: Božo Krušlin (član povjerenstva)
• Committee member: Josip Juras (član povjerenstva)
• Granter: University of Zagreb; School of Medicine; Zagreb
• Defense date and country: 2024-02-23, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Basic Medical Sciences; Human Genetics, Genomics and Proteomics
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Clinical Medical Sciences; Gynecology and Obstetrics
• Universal decimal classification (UDC): 616 - Pathology. Clinical medicine

Abstract

Jedan od najčešćih uzroka intrauterinog zastoja u rastu (IUGR) je nedostatna funkcija posteljice. IUGR se pojavljuje u oko 10% trudnoća te uzrokuje povećanje fetalnog i neonatalnog morbiditeta i mortaliteta. Unatoč presudnoj ulozi signalnih puteva Wnt i Hedgehog (Hh) u embrionalnom razvoju te razvoju posteljice, njihova uloga u nastanku IUGR-a još nije dovoljno istražena. U ovoj je studiji analizirana ekspresija pozitivnih regulatora signalnog puta Wnt, proteina WNT5A i β-katenina, te ekspresija proteina SUFU koji je negativni regulator signalnog puta Hh,. Proteinska ekspresija je analizirana imunohistokemijom (IHC) u uzorcima 34 posteljice s IUGR-om te 18 posteljica iz urednih jednoplodnih terminskih trudnoća te dodatno provjerena na razini mRNA metodom analize reverzne transkripcije i kvantitativne lančane reakcije polimerazom (RT-qPCR). Epigenetski mehanizmi regulacije ekspresije gena SUFU istraženi su određivanjem metilacijskog obrasca DNA u promotoru gena SUFU PCR- om ovisnim o metilaciji (MSP) te RT-qPCR analizom ekspresije miR-214-3p i miR-378a-5p. Proteinska ekspresija WNT5A je bila viša u endotelnim stanicama posteljičnih resica kod IUGR-a u odnosu na kontrolnu skupinu. Proteinska ekspresija β-katenina je bila povišena u trofoblastu i endotelnim stanicama kod IUGR-a, dok je proteinska ekspresija SUFU bila povišena u trofoblastu posteljica s IUGR-om. Promotor gena SUFU je ostao nemetiliran u obje skupine, dok je kod posteljica s IUGR-om nađena smanjena ekspresija miR-214-3p i miR-378a-5p. Povišena proteinska ekspresija SUFU u posteljica s IUGR-om u kontekstu također povišene proteinske ekspresije WNT5A i β-katenina potvrđene i korelacijskom analizom proteinske ekspresije β-katenina i SUFU ukazuje na moguću ulogu SUFU kao pozitivnog i negativnog regulatora u integriranju signalnih puteva Wnt i Hh u posteljica s IUGR-om. Čini se da bi miRNA, a ne DNA metilacija, mogao biti epigenetski mehanizam u reguliranju genske ekspresije SUFU u patogenezi posteljica sa IUGR-om.

Abstract (english)

Placental insufficiency is one of the most common causes of intrauterine growth restriction (IUGR). IUGR affects ~10% of preg-nancies and increases fetal and neonatal morbidity and mortality. Although Wnt and Hh pathways are crucial for embryonic development and placentation, their role in the pathology of IUGR is still not sufficiently explored.
The present study analyzed the expression of positive regulators of the Wnt signaling pathway, WNT5A, and β‑catenin, and the expression of the Hh signaling pathway negative regulator, suppressor of fused (SUFU). Immunohistochemical and reverse transcription‑quantitative PCR (RT‑qPCR) assays were performed on 34 IUGR and 18 placental tissue samples from physiologic singleton term-pregnancies. Epigenetic mechanisms of SUFU gene regulation were also investigated by methylation‑specific PCR analysis of its promoter and RT‑qPCR analysis of miR‑214‑3p and miR‑378a‑5p expression. WNT5A protein expression was higher in endothelial cells of placental villi from IUGR group compared with controls. That was also the case for the expression of β-catenin protein in trophoblasts and endothelial cells and SUFU protein in trophoblasts from IUGR placentas. The SUFU gene promoter remained unmethylated in all tissue samples, while miR‑214‑3p and miR‑378a‑5p were downregulated in IUGR. The present results of higher SUFU protein expression in IUGR placentas in the context of higher WNT5A and β-catenin protein expression confirmed with SUFU and β-catenin protein expression correlation analysis suggest a possible function of SUFU as both a positive and negative regulator in the integration of Wnt and Hh signaling in IUGR. DNA methylation did not appear to be a mechanism of SUFU regulation in the pathogenesis of IUGR, but its expression could be regulated by miRNA targeting.

• Keywords: intrauterini zastoj u rastu - IUGR; posteljica; WNT5A; β-katenin; SUFU; signalni put Wnt; signalni put Hh; DNA metilacija; miRNA
• Keywords (english): intrauterine growth restriction - IUGR; placenta; WNT5A; β-catenin; SUFU; Wnt signaling pathway; Hh signaling pathway; DNA methylation; miRNA
• Language: croatian
• URN:NBN: urn:nbn:hr:105:517468
• Project: Number: KK.01.1.1.01.0008; Title: Reproduktivna i regenerativna medicina - istraživanje novih platformi i potencijala; Leader: Ana Katušić Bojanac; Jurisdiction: Croatia; Funder: MZO
• Study programme: Title: Biomedicine and Health Sciences; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, područje biomedicine i zdravstvo (doktor/doktorica znanosti, područje biomedicine i zdravstvo)
• Type of resource: Text
• Extent: 133 str.
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-03-12 08:32:03