ABSTRACT
ABSTRACT Inulin is an effective prebiotic and its potential in modulating systemic immunity have been proposed. A subpopulation of T cells, named T regulatory cells (Tregs), expressing the Forkhead boxP3 transcription factor are key mediators of peripheral tolerance and suppress undesirable immune responses. These Tregs can be induced by cytokine transforming growth factor beta (TGF-β) and interleukin 10 (IL-10). This work aimed to evaluate inulin effects on human peripheral blood mononuclear cells (PBMC) in vitro. PBMC were incubated with inulin, and the expression of TGF-(1, FOXP3 and IL-10 was analyzed. Increased supernatant IL-10 levels were observed in PBMC of inulin-treated group (p=0.03). Moreover, FOXP3 gene expression was 7.6 fold higher in inulin-treated PBMC, whereas a trend in TGF-β1 expression was detected (p=0.055). These data suggest that inulin induces an immunosuppressive environment in cultured PBMC by promoting FOXP3 gene expression and IL-10 secretion. These studies offer prospects for further fundamental research in this field.
ABSTRACT
A Dietilnitrosamina (DEN), uma substância reconhecidamente hepatotóxica e carcinogênica, foiutilizada na indução da necrose hepática centrolobular em ratos isogênicos Lewis divididos em 5 grupos de 5 animais. O objetivo deste estudo foi avaliar o efeito quimiopreventivo da epigalocatequina-3-galato (EGCG), de Camellia sinensis (chá verde) no tratamento da hepatotoxicidade celular induzida pela DEN. Foi mensurada a concentração sérica da alanina aminotransferase (ALT) e aspartato aminotransferase(AST) dos diferentes grupos experimentais. No ensaio bioquímico para AST e ALT, houve diferença significativa entre os valores médios do grupo controle (163±70,32) comparado ao grupo DEN (1631±1039,44), sugerindo que a DEN influencia na função hepática. Entretanto, não houve diferença significativa entre o grupo DEN e o tratado com epigalocatequina. A lactato desidrogenase (LDH) éconsiderada um marcador bioquímico comum para avaliação da progressão tumoral, e em relação ao LDH, as amostras não apresentaram diferenças significativas entre o grupo DEN (1385,5±43,13) e DEN + EGCG 150mg ou DEN + EGCG 200mg 1537,5±1010,45). Neste trabalho foi demonstrado que a epigalocatequina nas concentrações de 150 e 200 mg/Kg não induziram alterações hepáticas e também não foi possível verificar nenhuma quimioproteção pela EGCG em animais inicialmente tratados comDEN durante 24 horas. Sendo assim, novos experimentos com diferentes concentrações de EGCG sãonecessários para comprovar seu possível efeito quimioprotetor.
Diethylnitrosamine (DEN), a known hepatotoxic and carcinogenic substance, was used in the induction of centrilobular hepatic necrosis in isogenic Lewis rats divided into 5 groups with 5 animals. The aim of this study was to evaluate the chemopreventive effect of epigallocatechin-3-gallate (EGCG)from Camellia sinensis (green tea) in the treatment of cellular hepatotoxicity induced by DEN. It was measured the serum concentration of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) of the different experimental groups. In the biochemistry assay for AST and ALT, there was significant difference between median values of control group (163±70.32) compared to DEN group(1631±1039.44), suggesting that DEN influences on hepatic function. However, there was no significant difference between DEN group to that treated with epigallocatechin. Lactate dehydrogenase (LDH) is considered a common biochemical marker for evaluation of tumor progression, and regarding LDH,the samples presented no significant differences between the DEN group (1385.5±43.13) and DEN + EGCG 150mg or DEN + EGCG 200mg (1537.5± 1010.45). In this work it was demonstrated that epigallocatechin concentrations of 150 and 200 mg/kg did not induce liver alterations and though was not verified any chemoprotective effect by EGCG in animals initially treated with DEN for 24 hours. Moreover, new experiments with different concentrations of EGCG are needed to verify its possiblechemoprotector effect.