Fabry disease (FD) is an X-linked rare metabolic disorder due to a mutation in the galactosidase alpha gene (GLA) that encodes for the lysosomal enzyme alpha-galactosidase A (α-galA) involved in the metabolism of glycosphingolipid as globotriaosylceramide (Gb3) and derivatives. The deficient expression and activity of α-galA cause lysosomal accumulation of its substrates in various organs arising a systemic disease. The current available treatment for all FD patients is the enzyme replacement therapy (ERT) which consist in an intravenous administration of recombinant α-galA in order to replace the impaired enzymatic activity and reduce intracellular storage of Gb3. Nevertheless, long-term studies showed no clear evidence that ERT could alter the natural course of cardiac, cerebrovascular and renal disease, suggesting on one hand that these adverse outcomes do not entirely depend on the single accumulation of glycosphingolipids, on the other that additional therapies targeted at specific secondary mechanisms can halt the progress of cardiac and cerebrovascular disease and the nephropathy that occur in Fabry patients. Oxidative stress has a primary role in the induction of cardiovascular-renal remodelling. It has been shown that Gb3 accumulation induces oxidative stress in terms of increased proinflammatory cytokines and reduced nitric oxide production. Therefore, it could also be involved in the onset of cardiovascular-renal complications in FD. Hence, in the first phase of this study we aimed to evaluate the status of oxidative stress in Fabry patients under ERT, compared with a group of healthy patients as control. In the second phase, we evaluated the changes in the oxidative profile in FD before the start of the enzymatic therapy, after 12 months of ERT and after 6 months of additional treatment with green tea. These evaluations were performed ex vivo on 10 treated patients and 10 healthy controls in the first phase and, in the second phase, on 10 Fabry patients enrolled before the start of therapy. Specifically, we evaluated the protein expression of p22phox and HO-1, the phosphorylation of MYPT-1 and ERK 1/2, plasma levels of malondialdehyde (MDA). The results of this project showed that OxSt is clearly present and active in Fabry patients and that the treatment with ERT, and particularly with the adjunctive antioxidant therapy with green tea, led to an attenuation of the oxidative profile. In fact, protein expression of p22phox, MDA levels, and MYPT-1 phosphorylation were significantly higher in patients compared to healthy subjects. p22phox and MYPT-1 phosphorylation that significantly decreased after ERT, unlike MDA levels that were not statistically reversed by the enzymatic treatment. However, the antioxidant supplementation significantly reduced the levels of these markers. In contrast, protein expression of HO-1 and phosphorylation of ERK 1/2 were significantly lower in treated subjects than controls. Compared to baseline, the first 12 months of ERT resulted in a reduction of HO-1, while the phosphorylation state of ERK 1/2 remained unchanged; markers that however significantly decreased after 6 months of green tea supplementation. In conclusion, this study showed an altered oxidative stress response in FD that should be taken into consideration in the management and follow-up of these patients. Our preliminary data also documented an antioxidant effect exerted by ERT itself, which was further amplified by the treatment with green tea on top of ERT. These data while on one hand highlight the fundamental importance of an early diagnosis and treatment of FD, on the other suggest the need of adjuvant antioxidant treatments to prevent or improve specific disease manifestations.
La malattia di Fabry è una rara disfunzione metabolica conseguente ad una mutazione nel gene galattosidasi alpha (GLA) localizzato nel cromosoma X che codifica per l’enzima α-galattosidasi A (α-galA) implicato nel metabolismo dei glicosfingolipidi, in modo particolare della globotriaosilceramide (Gb3) e derivati. Le differenti mutazioni comportano un’alterata espressione ed attività dell’enzima α-galA con il conseguente accumulo dei suoi substrati all’interno dei lisosomi e l’insorgenza di una malattia sistemica. L'attuale linea di trattamento è la terapia enzimatica sostitutiva (ERT) la quale, nel lungo termine, non è in grado di alterare il progressivo decorso della malattia. Questo pone l’attenzione sulla possibilità che le complicanze a livello cardiovascolare e renale siano dovute a meccanismi secondari all’accumulo di Gb3, suggerendo la necessità di affiancare l’ERT con terapie aggiuntive. Tra gli induttori di rimodellamento cardiovascolare-renale, lo stress ossidativo ha un ruolo primario. Considerato che nei pazienti con malattia di Fabry è stato dimostrato che l’accumulo di Gb3 induce stress ossidativo in termini di incremento di citochine proinfiammatorie e riduzione della produzione di ossido nitrico, è ragionevole pensare ad un importante coinvolgimento dello stress ossidativo nella malattia di Fabry. A tal scopo, nella prima fase di questo studio è stato valutato lo stato di attivazione dello stress ossidativo nei pazienti Fabry in trattamento con ERT, a confronto con un gruppo di pazienti sani. Nella seconda fase invece è stata valutata la variazione del profilo ossidativo prima dell’inizio della terapia, dopo 12 mesi di trattamento con la terapia enzimatica sostitutiva e dopo 6 mesi di trattamento antiossidante aggiuntivo con tè verde. Queste valutazioni sono state condotte ex vivo su 10 pazienti trattati e 10 controlli sani nella prima fase e, nella seconda fase, su 10 pazienti Fabry arruolati prima dell’inizio della terapia. Nello specifico è stata valutata: l’espressione proteica di p22phox ed HO-1, la fosforilazione della MYPT-1 e delle ERK 1/2, i livelli plasmatici di MDA. Da questo studio emerge chiaramente come nei pazienti Fabry ci sia uno stato di stress ossidativo attivo. Questo sbilancio ossidativo sembra essere parzialmente alleviato dalla terapia con ERT, ma la somministrazione sinergica di tè verde porta ad una significativa riduzione dei marker ossidativi analizzati. Infatti, l’espressione proteica di p22phox, i livelli di MDA e la fosforilazione della MYPT-1 risultano significativamente maggiori nei pazienti rispetto ai soggetti sani. p22phox e fosforilazione di MYPT-1 che si riducono significativamente in seguito alla terapia a differenza dei livelli di MDA; tuttavia, l’integrazione antiossidante contribuisce ad una significativa riduzione dei tre marker. Al contrario, l’espressione proteica di HO-1 e la fosforilazione di ERK 1/2 sono significativamente più basse nei soggetti trattati rispetto ai controlli. Il confronto con i primi 12 mesi di trattamento dimostra una riduzione dei livelli di HO-1 rispetto al baseline ma non della fosforilazione delle ERK 1/2, entrambi valori che significativamente diminuiscono dopo 6 mesi di trattamento antiossidante. In conclusione, da questo studio emerge un’alterata reazione dello stress ossidativo nei pazienti affetti da malattia di Fabry che dovrebbe essere tenuta in considerazione nella gestione e nel follow-up dei pazienti. Da questi dati preliminari emerge inoltre un parziale ruolo protettivo dell’ERT nella riduzione dello stress ossidativo, in seguito amplificato dalla terapia antiossidante con tè verde. Questo da un lato evidenzia ulteriormente l'importanza di una diagnosi precoce e di un inizio tempestivo del trattamento enzimatico, dall'altro suggerisce la necessità di trattamenti antiossidanti adiuvanti per prevenire o risolvere specifiche manifestazioni della malattia.
Assessment of oxidative stress and cardiovascular-renal remodelling in the X-linked rare Fabry disease. Evaluation of the antioxidant effect of green tea treatment on top of Enzyme Replacement Therapy / Bertoldi, Giovanni. - (2022 May 18).
Assessment of oxidative stress and cardiovascular-renal remodelling in the X-linked rare Fabry disease. Evaluation of the antioxidant effect of green tea treatment on top of Enzyme Replacement Therapy
BERTOLDI, GIOVANNI
2022
Abstract
Fabry disease (FD) is an X-linked rare metabolic disorder due to a mutation in the galactosidase alpha gene (GLA) that encodes for the lysosomal enzyme alpha-galactosidase A (α-galA) involved in the metabolism of glycosphingolipid as globotriaosylceramide (Gb3) and derivatives. The deficient expression and activity of α-galA cause lysosomal accumulation of its substrates in various organs arising a systemic disease. The current available treatment for all FD patients is the enzyme replacement therapy (ERT) which consist in an intravenous administration of recombinant α-galA in order to replace the impaired enzymatic activity and reduce intracellular storage of Gb3. Nevertheless, long-term studies showed no clear evidence that ERT could alter the natural course of cardiac, cerebrovascular and renal disease, suggesting on one hand that these adverse outcomes do not entirely depend on the single accumulation of glycosphingolipids, on the other that additional therapies targeted at specific secondary mechanisms can halt the progress of cardiac and cerebrovascular disease and the nephropathy that occur in Fabry patients. Oxidative stress has a primary role in the induction of cardiovascular-renal remodelling. It has been shown that Gb3 accumulation induces oxidative stress in terms of increased proinflammatory cytokines and reduced nitric oxide production. Therefore, it could also be involved in the onset of cardiovascular-renal complications in FD. Hence, in the first phase of this study we aimed to evaluate the status of oxidative stress in Fabry patients under ERT, compared with a group of healthy patients as control. In the second phase, we evaluated the changes in the oxidative profile in FD before the start of the enzymatic therapy, after 12 months of ERT and after 6 months of additional treatment with green tea. These evaluations were performed ex vivo on 10 treated patients and 10 healthy controls in the first phase and, in the second phase, on 10 Fabry patients enrolled before the start of therapy. Specifically, we evaluated the protein expression of p22phox and HO-1, the phosphorylation of MYPT-1 and ERK 1/2, plasma levels of malondialdehyde (MDA). The results of this project showed that OxSt is clearly present and active in Fabry patients and that the treatment with ERT, and particularly with the adjunctive antioxidant therapy with green tea, led to an attenuation of the oxidative profile. In fact, protein expression of p22phox, MDA levels, and MYPT-1 phosphorylation were significantly higher in patients compared to healthy subjects. p22phox and MYPT-1 phosphorylation that significantly decreased after ERT, unlike MDA levels that were not statistically reversed by the enzymatic treatment. However, the antioxidant supplementation significantly reduced the levels of these markers. In contrast, protein expression of HO-1 and phosphorylation of ERK 1/2 were significantly lower in treated subjects than controls. Compared to baseline, the first 12 months of ERT resulted in a reduction of HO-1, while the phosphorylation state of ERK 1/2 remained unchanged; markers that however significantly decreased after 6 months of green tea supplementation. In conclusion, this study showed an altered oxidative stress response in FD that should be taken into consideration in the management and follow-up of these patients. Our preliminary data also documented an antioxidant effect exerted by ERT itself, which was further amplified by the treatment with green tea on top of ERT. These data while on one hand highlight the fundamental importance of an early diagnosis and treatment of FD, on the other suggest the need of adjuvant antioxidant treatments to prevent or improve specific disease manifestations.File | Dimensione | Formato | |
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