Vloga nekodirajočih RNA pri anabolnem zdravljenju osteoporoze s teriparatidom

Vrščaj, Lucija Ana (author), Marc, Janja (mentor), Ostanek, Barbara (comentor)

Osteoporoza je najpogostejša presnovna bolezen kosti, ki s starostjo napreduje. Zaznamuje jo nizka kostna masa ter porušena mikroarhitektura kostnega tkiva, kar poveča lomljivost kosti. Nastane zaradi neravnovesja med razgradnjo kosti, ki jo povzročajo osteoklasti, in izgradnjo kosti, ki jo opravljajo osteoblasti. Za zdravljenje osteoporoze se večinoma uporablja antiresorptivne zdravilne učinkovine, kot so bisfosfonati in denosumab, ki zmanjšujejo resorpcijo kosti, a ne spodbujajo tvorbe kosti. Teriparatid (TPTD) pa je prva registrirana osteoanabolna zdravilna učinkovina, ki spodbuja kostno tvorbo, vendar je učinek TPTD na kosti odvisen od načina odmerjanja. Intermitentno odmerjanje ima anabolen učinek, kontinuirano pa poveča razgradnjo kosti. Čeprav predstavlja zdravljenje s TPTD učinkovitejši pristop od tistega z bisfosfonati, do zlomov še vedno prihaja, kar ostaja nepojasnjeno. V naši doktorski nalogi smo se osredotočili na proučevanje epigenetskih dejavnikov, ki bi lahko bili vpleteni v neodzivnost na zdravljenje s TPTD, in sicer na nekodirajoče RNA (ncRNA), vključno z mikroRNA (miRNA), dolgimi nekodirajočimi RNA (lncRNA) in krožnimi RNA (circRNA). Cilj doktorske naloge je bil raziskati vlogo ncRNA pri uravnavanju kostne remodelacije in njihovo povezavo z osteoanabolnimi učinki TPTD. Po tretiranju s TPDT smo izvedli analizo transkriptoma mezenhimskih matičnih celic (MSC), kot izvorne celice iz katerih se razvijajo tudi osteoblasti ter prvi odkrili razlike v izražanju različnih nekodirajočih RNA. S pomočjo bioinformatične analize smo odkrili ključne molekule miRNA in tri najpomembnejše signalne poti, vključene v anabolno delovanje TPTD, in sicer tiste ki uravnavajo pluripotentnost matičnih celic, signalno pot Hippo in signalno pot TGF-ß. Za izbrane miRNA smo na kliničnih vzorcih dokazali, da imajo potencial zgodnjih bioloških označevalcev (ne)odziva na zdravljenje s TPTD. Na koncu smo na osnovi funkcijske analize izpostavili 3 miRNA (hsa-miR-375-3p, hsa-miR-20b-5p, hsa-miR-31-3p), ki spodbujajo osteogenezo, in 3 (hsa-miR-133a-3p, hsa-miR-31-3p, hsa-miR-363-3p), ki zavirajo adipogenezo MSC. Z izsledki naših raziskav smo poglobili razumevanje molekularnih mehanizmov delovanja TPTD, ki bi lahko pripomogli k personaliziranemu zdravljenju osteoporoze.

• Language: Slovenian
• Keywords: osteoporoza, nekodirajoče RNA, teriparatid, mezenhimske matične/ stromalne celice, mikro RNA
• Work type: Doctoral dissertation
• Organization: FFA - Faculty of Pharmacy
• Year: 2024
• PID: 20.500.12556/RUL-164576
• Publication date in RUL: 01.11.2024

Secondary language

• Language: English
• Title: The role of non-coding RNAs in anabolic treatment of osteoporosis with teriparatide

Abstract

Osteoporosis, the most common metabolic bone disease, increases with age and is characterized by low bone mass and disrupted bone microarchitecture, leading to increased bone fragility. It arises from an imbalance between bone resorption by osteoclasts and bone formation by osteoblasts. Osteoblasts originate from mesenchymal stem cells (MSCs) in the bone marrow. Current osteoporosis treatments include antiresorptive drugs like bisphosphonates and denosumab, which reduce bone resorption but do not promote bone formation. Teriparatide (TPTD) is one of the few osteoanabolic drugs that stimulate bone formation. TPTD’s effect on bones depends on dosing: intermittent dosing has an anabolic effect, while continuous dosing increases bone resorption. Although TPTD treatment is more effective than bisphosphonates, fractures still occur. Therefore, therapy effectiveness is crucial, and research shows that it varies among individuals, which remains unexplained. This variability is likely due to epigenetic factors, including non-coding RNAs (ncRNAs) such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs). This doctoral thesis aimed to investigate the role of ncRNAs in bone remodeling and their connection to the osteoanabolic effects of TPTD. For the first time, we performed a transcriptomic analysis of MSCs treated with TPTD, revealing differences in the expression of miRNAs, lncRNAs, mRNAs, and circRNAs. Through bioinformatic analysis, we identified key miRNAs and signaling pathways involved in TPTD’s effects, including pathways regulating stem cell pluripotency, the Hippo pathway, and the TGF-β pathway. We demonstrated that selected miRNAs have potential as early biological markers of response to TPTD treatment. Finally, functional analyses highlighted 3 miRNAs (hsa-miR-375-3p, hsa-miR-20b-5p, hsa-miR-31-3p) that promote osteogenesis and 3 miRNAs (hsa-miR-133a-3p, hsa-miR-31-3p, hsa-miR-363-3p) that inhibit MSC adipogenesis. Our findings deepen the understanding of TPTD's molecular mechanisms, which could lead to personalized osteoporosis treatment.

• Keywords: osteoporosis, non-coding RNAs, teriparatide, mesenchymal stem/ stromal cells, micro RNA