Določanje katalitične aktivnosti podenot β5c in β5i cirkulirajočih proteasomov v vzorcih krvi bolnikov s kroničnimi vnetnimi črevesnimi boleznimi

Korbar, Karmen (avtor), Gobec, Martina (mentor), Smrdel, Lara (komentor)

Proteasomi so del ubikvitin-proteasomskega sistema, ki je odgovoren za razgradnjo večine znotrajceličnih proteinov. Poznamo več vrst proteasomov, najbolj pogost pa je konstitutivni proteasom in imunoproteasom. Proteasome, ki se nahajajo v ekstracelularnem prostoru, imenujemo cirkulirajoči proteasomi. Njihova koncentracija v plazmi je povišana pri različnih patoloških stanjih, zaradi česar predstavljajo morebitne nove biološke označevalce za spremljanje teh bolezni. V magistrski nalogi smo želeli raziskati, ali bi lahko bili uporabni tudi pri diagnostiki kroničnih vnetnih črevesnih boleznih, pri katerih je prisotno kronično vnetje prebavnega trakta. Diagnostika in spremljanje aktivnosti teh bolezni je zahtevno in dolgotrajno, saj se spremlja klinične simptome, biokemijske parametre vnetja v krvi, pregleda vzorec blata in opravi endoskopske ter histološke preiskave vnetega tkiva. Naš namen je bil ugotoviti, ali povišana koncentracija in aktivnost cirkulirajočih proteasomov korelira s stopnjo vnetja pri bolnikih. Osredotočili smo se na proteolitsko aktivne podenote β5c in β5i. Izbranim nehemoliziranim vzorcem plazme smo s tehniko ELISA določili koncentracijo podenot β5. Za aktivnost podenot smo določili kinetični profil z merjenjem fluorescence, pri čemer smo metodo predhodno optimizirali. Pridobljene rezultate smo korelirali z biokemijskimi označevalci vnetja. Prav tako smo preverili, ali nivo podenot oziroma njihova katalitična aktivnost korelirata z rezultati kliničnih točkovnikov HBI in MAYO, ki se uporabljata za oceno aktivnosti bolezni. Korelacije med izbranimi parametri v večini primerov nismo dokazali in tako ne moremo potrditi, da koncentracija ali aktivnost cirkulirajočih proteasomov odražata aktivnost bolezni. V bodoče so potrebne nadaljnje študije, predvsem na večjem številu vzorcev, da bi ugotovili, ali cirkulirajoči proteasomi sovpadajo z aktivnostjo kroničnih vnetnih črevesnih bolezni.

• Jezik: Slovenski jezik
• Ključne besede: cirkulirajoči proteasomi, kronične vnetne črevesne bolezni, biokemični označevalci
• Vrsta gradiva: Magistrsko delo/naloga
• Organizacija: FFA - Fakulteta za farmacijo
• Leto izida: 2024
• PID: 20.500.12556/RUL-165909
• Datum objave v RUL: 13.12.2024

Sekundarni jezik

• Jezik: Angleški jezik
• Naslov: Determination of the catalytic activity of β5c and β5i subunits of circulating proteasomes in blood samples from patients with chronic inflammatory bowel diseases

Izvleček

Proteasomes are part of the ubiquitin-proteasome system, which is responsible for protein degradation. There are several types of them, with the most common ones being the constitutive proteasome and the immunoproteasome. Proteasomes found in the extracellular space, are called circulating proteasomes. Their concentration in plasma is elevated in various pathological conditions, suggesting they could become a novel biomarker for monitoring the severity of the disease. We aimed to investigate whether they could also be useful in diagnosing chronic inflammatory bowel diseases, which are characterized by chronic inflammation of the gastrointestinal tract. Diagnosis and monitoring of disease activity are complex and time-consuming, as they involve tracking clinical symptoms, measuring markers of inflammation, analyzing stool samples, and performing endoscopic and histological examinations of inflamed tissue. We wanted to determine whether elevated concentrations and activity of circulating proteasomes correlate with the degree of inflammation in patients. We focused on the proteolytically active β5c and β5i subunits. Using the ELISA technique, we determined the concentration of β5 subunits in the selected unhemolyzed samples. The activity of β5 subunits was determined with an optimized method by measuring flourescence and calculating kinetic profiles. We then used statistical analysis to determine correlation coefficients between biochemical markers of inflammation and our results. We also checked whether these correlated with the results of the scoring systems HBI and MAYO, which assess disease activity. Correlations between the selected parameters were mostly not demonstrated. Based on our results, the concentration and activity of circulating proteasomes do not reflect the actual disease activity. Most of the results of the statistical tests were not statistically significant, as we had a small number of samples. Further studies are needed to determine whether circulating proteasomes could be used for monitoring chronic inflammatory bowel diseases.

• Ključne besede: circulating proteasomes, chronic inflammatory bowel diseases, biomarkers