TY - JOUR
T1 - Radical scavenging abilities of fish MT-A and mussel MT-10 metallothionein isoforms
T2 - An ESR study
AU - Buico, Alessandra
AU - Cassino, Claudio
AU - Dondero, Francesco
AU - Vergani, Laura
AU - Osella, Domenico
N1 - Funding Information:
This work received financial support from ATF (Alessandria), C.I.R.C.M.S.B (Bari) and University of Genova. Research was carried out within the framework of the European Cooperation COST D39 action (metallo-drug design and action) and B16 action (multidrug resistance reversal). Helpful discussion with Professor Edward Rosenberg (University of Montana, USA) is gratefully acknowledged.
PY - 2008/4
Y1 - 2008/4
N2 - Metallothioneins (MTs) are cysteine-rich proteins involved in homeostasis of essential metals, detoxification of toxic metals and scavenging of free radicals. Scavenging of the stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical was measured by means of ESR spectroscopy for two recombinant MTs from aquatic species: MT-10 from the sea mussel Mytilus galloprovincialis, and MT-A from the fish Oncorhyncus mykiss. Both the zinc- and the cadmium-loaded forms (Zn7-MTs and Cd7-MTs) were analysed, using the commercial MT-II (Zn7-MT-II and Cd7-MT-II, respectively) from rabbit liver as a reference. A decrease in the scavenging ability was observed for all the three MTs passing from the Zn- to the Cd-loaded forms, because of the higher stability of the Cd-mercapto complex. The Zn7-MTs from aquatic species were more effective in scavenging DPPH signal than the rabbit Zn7-MT-II (2.8 and 4-folds, respectively). Similar results were obtained also for the Cd7-MTs, thus confirming the stronger antioxidant power of MTs from aquatic organisms compared with the rabbit MT-II. Moreover, mussel MT-10 was more active in DPPH scavenging than fish MT-A. When the complete release of metals from MTs was obtained by lowering the pH to 3 or, alternatively, by adding the chelating agent diethylenetriaminepentaacetic acid (DTPA), an increase in the scavenging ability of MTs was observed.
AB - Metallothioneins (MTs) are cysteine-rich proteins involved in homeostasis of essential metals, detoxification of toxic metals and scavenging of free radicals. Scavenging of the stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical was measured by means of ESR spectroscopy for two recombinant MTs from aquatic species: MT-10 from the sea mussel Mytilus galloprovincialis, and MT-A from the fish Oncorhyncus mykiss. Both the zinc- and the cadmium-loaded forms (Zn7-MTs and Cd7-MTs) were analysed, using the commercial MT-II (Zn7-MT-II and Cd7-MT-II, respectively) from rabbit liver as a reference. A decrease in the scavenging ability was observed for all the three MTs passing from the Zn- to the Cd-loaded forms, because of the higher stability of the Cd-mercapto complex. The Zn7-MTs from aquatic species were more effective in scavenging DPPH signal than the rabbit Zn7-MT-II (2.8 and 4-folds, respectively). Similar results were obtained also for the Cd7-MTs, thus confirming the stronger antioxidant power of MTs from aquatic organisms compared with the rabbit MT-II. Moreover, mussel MT-10 was more active in DPPH scavenging than fish MT-A. When the complete release of metals from MTs was obtained by lowering the pH to 3 or, alternatively, by adding the chelating agent diethylenetriaminepentaacetic acid (DTPA), an increase in the scavenging ability of MTs was observed.
KW - ESR spectroscopy
KW - Metal release
KW - Metallothionein
KW - Oxidative stress
KW - Radical scavenger
UR - http://www.scopus.com/inward/record.url?scp=40649101608&partnerID=8YFLogxK
U2 - 10.1016/j.jinorgbio.2007.12.012
DO - 10.1016/j.jinorgbio.2007.12.012
M3 - Article
SN - 0162-0134
VL - 102
SP - 921
EP - 927
JO - Journal of Inorganic Biochemistry
JF - Journal of Inorganic Biochemistry
IS - 4
ER -