Uptake and efflux of methylmercury in vitro: Comparison of transport mechanisms in C6, B35 and RBE4 cells

Inactivation by Hg2+ and methylmercury of the glutamine/amino acid transporter (ASCT2) reconstituted in liposomes: Prediction of the involvement of a CXXC motif by homology modelling

“…14 Differently from other amino acid or anion transporters [2,5,[7][8][9] ASCT2 is not involved in the absorption of mercurials nor as free molecules neither as conjugates. M a n u s c r i p t 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 …”

“…It was reported that the amino acid transport systems LAT1, LAT2 and B°, + , as well as organic anion transporters are able to trasport thiol conjugates of methylmercury, especially as cysteine-S-conjugates [2,5,[7][8][9]. To test whether ASCT2 could transport the mercuric reagents as conjugates with cysteine or N-acetylcysteine, the efflux procedure was used.…”

“…Indeed, it was reported that some transport systems catalyze the transport of mercuric compounds through biological membranes [2,[7][8][9]. Furthermore, interaction of mercuric compounds with transport systems of plasma membrane [1,[10][11][12][13][14][15] and also of mitochondrial membrane [16][17] have been reported to cause alterations of function.…”

Comparative study on methyl- and ethylmercury-induced toxicity in C6 glioma cells and the potential role of LAT-1 in mediating mercurial-thiol complexes uptake

“…As previously described, MeHg-induced toxicity is mediated by its interaction with thiol groups (Aschner and Syversen, 2005; Franco et al, 2009) and the interaction of MeHg with the sulfhydryl amino acid cysteine is important for its entrance into the CNS (as a MeHg-S-Cys complex), via specific amino acid transporters, such as LAT-1 (Mokrzan et al, 1995; Heggland et al, 2009; Farina et al, 2011b). On the other hand, although it is well known that EtHg may share some chemical and toxic properties with MeHg (Mutkus et al, 2005) and that it interacts with thiols, there are no studies investigating its potential interaction with cysteine and the formation of an EtHg-S-Cys type complex, as well as its potential toxicity and transport via the LAT system.…”

Effects on and transfer across the blood-brain barrier in vitro—Comparison of organic and inorganic mercury species

“…It has to be noted that the transport of MeHg across the blood-brain barrier involves both, uptake into and efflux from brain endothelial cells. Heggland et al postulated that LAT does not seem to be involved in the efflux of MeHg in vitro but that MeHg is transferred out of brain endothelial cells as a complex with glutathione (GSH), thereby using GSH-transporters [15]. In 2013 Zimmermann et al postulated a LAT system based uptake of MeHg-S-Cys as well as EtHg-S-Cys into C6 glioma cells, whereas MeHg and EtHg enter the cells by other mechanisms [16].…”