Inflammation and tissue regeneration follow injury and consequently they are unavoidably entangled. Understanding the molecular mechanisms underlying the regeneration process to develop drugs supporting tissue regeneration would be of great interest in a variety of clinical settings. High Mobility Group Box 1 (HMGB1) is a ubiquitous nuclear protein released by injured cells to act as a soluble message of tissue damage and to trigger inflammation and tissue regeneration. Our group previously reported that HMGB1 promotes inflammation or muscle regeneration upon acute injury and in muscular dystrophies by switching among mutually exclusive redox states (Tirone et al., 2018; Careccia et al., 2021). Previous data demonstrate that HMGB1 mainly derives from non-muscle cells in injured muscle and that leukocytes might act as transporters of HMGB1 in injured muscle (Ferrara et al., 2020). Hence, the aim of my thesis project is to evaluate the role of leukocyte derived-HMGB1 during muscle regeneration by exploiting immune cells-specific HMGB1 knockout (HMGB1 bmKO) mice recently generated in our laboratory. I induced acute muscle injury in HMGB1 bmKO and control mice by performing intramuscular injection of cardiotoxin, a widely used model to study muscle regeneration. To assess the regeneration process in these mice at different time points, I employed three distinct techniques, namely histological analyses, quantitative PCR for gene expression and Western blot analyses. This set of experiments has been performed to determine whether HMGB1 derived from leukocytes represents a key source of the protein during the regeneration process.
L'infiammazione e la rigenerazione dei tessuti seguono le lesioni e di conseguenza sono inevitabilmente intrecciate. La comprensione dei meccanismi molecolari alla base del processo di rigenerazione per sviluppare farmaci che supportino la rigenerazione dei tessuti sarebbe di grande interesse in diversi contesti clinici. L'High Mobility Group Box 1 (HMGB1) è una proteina nucleare ubiquitaria rilasciata dalle cellule danneggiate che agisce come messaggero solubile di danno tissutale capace di innescare l'infiammazione e la rigenerazione dei tessuti. Il nostro gruppo ha precedentemente riportato che HMGB1 promuove l'infiammazione o la rigenerazione muscolare in caso di lesioni acute e nelle distrofie muscolari passando da stati redox mutuamente esclusivi (Tirone et al., 2018; Careccia et al., 2021). Dati precedenti dimostrano che nel muscolo leso l'HMGB1 deriva principalmente da cellule non muscolari e che i leucociti potrebbero agire come trasportatori di HMGB1 nel sito di danno (Ferrara et al., 2020). Pertanto, l'obiettivo del mio progetto di tesi è valutare il ruolo dell'HMGB1 derivato dai leucociti durante la rigenerazione muscolare, sfruttando topi knockout per HMGB1 nelle cellule immunitarie (HMGB1 bmKO) recentemente generati nel nostro laboratorio. Ho indotto una lesione muscolare acuta in topi HMGB1 bmKO e in topi di controllo mediante iniezione intramuscolare di cardiotossina, un modello ampiamente utilizzato per studiare la rigenerazione muscolare. Per valutare il processo di rigenerazione in questi topi a diversi time points, ho impiegato tre tecniche distinte, ovvero analisi istologiche, PCR quantitativa per l'espressione genica e analisi Western blot. Questa serie di esperimenti è stata eseguita per determinare se l'HMGB1 derivato dai leucociti rappresenti una fonte chiave della proteina durante il processo di rigenerazione.
Il ruolo di HMGB1 derivante dai leucociti nella rigenerazione muscolare
OLDANI, PAOLA
2021/2022
Abstract
Inflammation and tissue regeneration follow injury and consequently they are unavoidably entangled. Understanding the molecular mechanisms underlying the regeneration process to develop drugs supporting tissue regeneration would be of great interest in a variety of clinical settings. High Mobility Group Box 1 (HMGB1) is a ubiquitous nuclear protein released by injured cells to act as a soluble message of tissue damage and to trigger inflammation and tissue regeneration. Our group previously reported that HMGB1 promotes inflammation or muscle regeneration upon acute injury and in muscular dystrophies by switching among mutually exclusive redox states (Tirone et al., 2018; Careccia et al., 2021). Previous data demonstrate that HMGB1 mainly derives from non-muscle cells in injured muscle and that leukocytes might act as transporters of HMGB1 in injured muscle (Ferrara et al., 2020). Hence, the aim of my thesis project is to evaluate the role of leukocyte derived-HMGB1 during muscle regeneration by exploiting immune cells-specific HMGB1 knockout (HMGB1 bmKO) mice recently generated in our laboratory. I induced acute muscle injury in HMGB1 bmKO and control mice by performing intramuscular injection of cardiotoxin, a widely used model to study muscle regeneration. To assess the regeneration process in these mice at different time points, I employed three distinct techniques, namely histological analyses, quantitative PCR for gene expression and Western blot analyses. This set of experiments has been performed to determine whether HMGB1 derived from leukocytes represents a key source of the protein during the regeneration process.È consentito all'utente scaricare e condividere i documenti disponibili a testo pieno in UNITESI UNIPV nel rispetto della licenza Creative Commons del tipo CC BY NC ND.
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https://hdl.handle.net/20.500.14239/15621