Signalni put Notch osteoklastnih progenitora u mišjem modelu reumatoidnoga artritisa

doctoral thesis

• Title (english): Notch signaling pathway of osteoclast progenitors in rheumatoid arthritis mouse model
• Author: Maša Filipović
• Mentor: Danka Grčević (mentor)
• Committee member: Dora Višnjić (predsjednik povjerenstva)
• Committee member: Krešo Bendelja (član povjerenstva)
• Committee member: Kristina Mlinac Jerković (član povjerenstva)
• Granter: University of Zagreb; School of Medicine; Zagreb
• Defense date and country: 2023-02-28, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Basic Medical Sciences; Human Physiology
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Basic Medical Sciences; Neuroscience
• Universal decimal classification (UDC): 612 - Physiology

Abstract

Lokalni i sustavni gubitak kosti u reumatoidnom artritisu posljedica je pojačane aktivnosti osteoklasta. Cilj ovog rada bio je istražiti učinke modulacije signalnog puta Notch na diferencijaciju osteoklastnih progenitora (OCP) i razgradnju kosti u mišjem modelu artritisa potaknutog kolagenom. OCP mišje koštane srži (CD45+Ly6G−CD3−B220−NK1.1− CD11b−/loCD115+) i slezene (CD45+Ly6G−CD3−B220−NK1.1−CD11b+CD115+) podrijetla su mijeloidne loze, izražavaju kemokinski receptor CX3CR1 i njihov je udio povećan u artritisu. OCP izražavaju sva četiri receptora signalnog puta Notch, a u artritisu povećan je udio OCP koji izražavaju receptore Notch 2 i 3. Poticanje OCP ligandima signalnog puta Notch JAG1 i DLL1 dovodi do inhibicije osteoklastogeneze. Obrada neutralizacijskim protutijelima na receptore Notch 1 i 2 pojačala je osteoklastogenezu in vitro, a obrada miševa s artritisom in vivo dovela je do povećanja udjela OCP. Koristeći transgenični mišji soj s utišanim signalnim putem Notch u OCP (CX3CR1CreERT2/RBP-J) uočili smo pojačanu osteoklastogenezu, a u mišjem soju s aktiviranom signalizacijom putem receptora Notch 1 u OCP (CX3CR1CreERT2/NICD1) uočili smo smanjenu osteoklastogenezu. U artritičnih miševa s utišanim signalnim putem Notch u OCP potvrdili smo pojačanu diferencijaciju osteoklastnih progenitora i pojačanu koštanu razgradnju koja dovodi do smanjenog volumena mineralizirane kosti. Naši rezultati potvrđuju inhibicijsku ulogu signalnog puta Notch u diferencijaciji osteoklastnih progenitora u artritisu.

Abstract (english)

Periarticular and systemic bone loss in rheumatoid arthritis is mediated by increased osteoclast activity. We aimed to determine the effects of Notch signaling modulation on osteoclast progenitor (OCP) differentiation and arthritis-induced bone resorption in murine collagen-induced arthritis. Murine bone marrow and splenic OCPs, identified as CD45+Ly6G−CD3−B220−NK1.1−CD11b−/loCD115+ and CD45+Ly6G−CD3−B220−NK1.1− CD11b+CD115+ cells, respectively, derived from the myeloid lineage are specifically increased in arthritis and express the chemokine receptor CX3CR1. OCPs express all four Notch receptors and are susceptible to regulation through Notch signaling. In arthritis, we observed an increase in the frequency of OCPs expressing Notch 2 and 3. Stimulation with Notch ligand JAG1 and DLL1 results in inhibition of osteoclast differentiation, and treatment with neutralizing antibodies targeting Notch 1 and 2 results in increased osteoclastogenesis in vitro and increased frequency of OCPs in mice treated in vivo. We used transgenic mice with Notch signaling inhibition (CX3CR1CreERT2/RBP-J) or Notch 1 overexpression (CX3CR1CreERT2/NICD1) in OCPs and observed stimulated osteoclastogenesis with Notch deletion and reduced osteoclastogenesis with Notch 1 signal activation. Arthritic mice with inhibition of Notch signaling in OCPs had increased osteoclast differentiation and reduced talar bone volume. Our results confirm an inhibitory role of Notch signaling in osteoclast differentiation during arthritis.

• Keywords: Osteoklasti; Osteogeneza; Signalni put Notch; Miševi; transgeni; Antitijela; neutralizirajuća; Resorpcija kostiju; Artritis; eksperimentalno
• Keywords (english): Osteoclasts; Osteogenesis; Receptors Notch; Mice; Transgenic; Antibodies; Neutralizing; Bone Resorption; Arthritis; Experimental
• Language: croatian
• URN:NBN: urn:nbn:hr:105:162886
• 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: 115 str.
• File origin: Born digital
• Access conditions: Open access
• Created on: 2023-03-24 08:24:47