Effect of coffee Melanoidin on human hepatoma HepG2 cells. Protection against oxidative stress induced by tert‐butylhydroperoxide

Abstract

Soluble high-molecular weight fraction (named melanoidin) from coffee brew was isolated by ultrafiltration, subsequently digested by simulating a gastric plus pancreatic digestive condition and partly characterized by CZE, gel-filtration and browning. The objective of the present study was to investigate the potential protective effect of the coffee melanoidin submitted to gastrointestinal digestion on cell viability (lactate dehydrogenase leakage) and redox status of cultured human hepatoma HepG2 cells submitted to oxidative stress induced by tert-butylhydroperoxide (t-BOOH). Concentration of reduced glutathione (GSH) and malondialdehyde (MDA), generation of reactive oxygen species (ROS) and activity of antioxidant enzymes glutathione peroxidase (GPx) and reductase (GR) were used as markers of cellular oxidative status. Pretreatment of cultured HepG2 cells with 0.5-10 microg/mL digested coffee melanoidin (DCM) for 2 or 20 h completely prevented the increase in cell damage and GR and partly prevented the decrease of GSH and the increase of MDA and GPx evoked by t-BOOH in HepG2 cells. In contrast, increased ROS generation induced by t-BOOH was not prevented when cells were pretreated with DCM. The results show that treatment of HepG2 cells with concentrations of DCM within the expected physiological range confers the cells a significant protection against an oxidative insult.

Protective effect ofLepidium sativumseed extract against hydrogen peroxide-induced cytotoxicity and oxidative stress in human liver cells (HepG2)

“…crude extracts from natural products exhibited significant cyto-protection against the H 2 O 2 in PC12 and SK-N-SH cells Sattayasai et al, 2013) and in liver cells against other toxicants (Alia et al, 2006;Goya et al, 2007;Martin et al, 2008;Verma et al, 2013).…”

“…However, the pre-treatment of HepG2 with LSE (5-25 mg/ml) significantly restored the decrease in the GSH level caused by H 2 O 2 . It is also known that the glutathione peroxidase catalyses GSH oxidation to GSSG at the expense of H 2 O 2 and glutathione reductase recycles oxidized GSH back to reduced GSH (Goya et al, 2007;Ursini et al, 1995). Therefore, it could be inferred that the LSE pre-exposed HepG2 quenches the intracellular damaging peroxide and recovers the concentration of reduced GSH.…”

Maillard Reaction Products in Processed Food: Pros and Cons

“…Furthermore, MRPs exhibit antioxidant activity (Açar et al, 2009;Chang et al, 2011;Chawla et al, 2009;Rao et al, 2011;Summa et al, 2008). Melanoidins from roasted coffee and biscuits exerted protective effects against oxidative stress on human hepatoma HepG2 cells (Goya et al, 2007;Martín et al, 2009). Regarding coffee antioxidant activity, more than 50% of the observed antioxidant activity is due to the low molecular weight compounds linked to the melanoidin skeleton, promoting a chelating ability that is also involved in the shelf life of the product .…”

Preconditioning with Maillard reaction products improves antioxidant defence leading to increased stress tolerance in cardiac cells

“…Food contains large quantities of Maillard reaction products (MRPs) or AGEs which arise during heating and processing and contribute to the characteristic flavour and colour. Such AGEs can be taken up by humans, have physiological consequences (Koschinsky et al 1997;Lindenmeier et al 2002;Vlassara et al 2002;Somoza 2005;Somoza et al 2006;Stirban et al 2006;Goya et al 2007) and also direct effects on gene expression and oxidative status in organisms. Nevertheless, our knowledge on possible adverse effects especially concerning the heart is far from being comprehensive (Chuyen 2006).…”