TY - JOUR
T1 - The effect of heavy metals on nicotinamide N-methyltransferase activity in vitro relating to Parkinson's disease
AU - Sugawara, Akiko
AU - Yokoyama, Hiroko
AU - Ohta, Mitsuhiro
AU - Maeda, Takafumi
AU - Tanaka, Kazuko
AU - Fukushima, Tetsuhito
PY - 2005/7
Y1 - 2005/7
N2 - Objective: The aims of this study were to determine the effects of heavy metals such as manganese on nicotinamide N-methyltransferase (EC 2.1.1.1) (NNMT) activity and to consider the possibility of involvement of NNMT activation in the pathogenesis of heavy metal induced Parkinson's disease. Methods: NNMT activity in supernatants separated from brain, liver and kidney homogenates of 5 elderly male Wistar rats by centrifugation were measured by high performance liquid chromatography system with fluorescence. NNMT activity under the conditon of 0.5 or 5.0 mM Mn2+, Fe2+, Cu2+ or Cd 2+ was compared with control (no metal ion existence). Results: NNMT activities in rat brain, liver and kidneys were significantly decreased by Cu2+, and those in the liver and kidneys were significantly decreased by Cd2+. Mn2+ reduced NNMT activity only in the liver. Fe2+ had no effect on NNMT activity. Conclusions: No metal increased NNMT activity in this study, contrary to our hypothesis. Further study is needed to clarify the reason why the effects of Mn2+ and Fe2+ which have a high relevance to Parkinson's disease on NNMT activity differ from those of Cu2+ and Cd2+.
AB - Objective: The aims of this study were to determine the effects of heavy metals such as manganese on nicotinamide N-methyltransferase (EC 2.1.1.1) (NNMT) activity and to consider the possibility of involvement of NNMT activation in the pathogenesis of heavy metal induced Parkinson's disease. Methods: NNMT activity in supernatants separated from brain, liver and kidney homogenates of 5 elderly male Wistar rats by centrifugation were measured by high performance liquid chromatography system with fluorescence. NNMT activity under the conditon of 0.5 or 5.0 mM Mn2+, Fe2+, Cu2+ or Cd 2+ was compared with control (no metal ion existence). Results: NNMT activities in rat brain, liver and kidneys were significantly decreased by Cu2+, and those in the liver and kidneys were significantly decreased by Cd2+. Mn2+ reduced NNMT activity only in the liver. Fe2+ had no effect on NNMT activity. Conclusions: No metal increased NNMT activity in this study, contrary to our hypothesis. Further study is needed to clarify the reason why the effects of Mn2+ and Fe2+ which have a high relevance to Parkinson's disease on NNMT activity differ from those of Cu2+ and Cd2+.
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U2 - 10.1265/ehpm.10.180
DO - 10.1265/ehpm.10.180
M3 - Article
C2 - 21432137
AN - SCOPUS:24944539173
SN - 1342-078X
VL - 10
SP - 180
EP - 183
JO - Environmental health and preventive medicine
JF - Environmental health and preventive medicine
IS - 4
ER -