Meeting Abstract
P1.113 Sunday, Jan. 4 Effects of Chelating Agents, Calcium Disodium EDTA and Diaminocyclohexanetetraacetic Acid, on Manganese Disruption of Mitochondrial Respiration in Crassostrea virginica CRAWFORD, Sherine*; SADDLER, Claudette; CARROLL, Margaret, A.; CATAPANE, Edward, J.; Medgar Evers College; Kingsborough Community College; Medgar Evers College; Medgar Evers College shamel11207@optonline.net
Manganese (Mn) is a metal that at excessive levels in brain produces Manganism which is similar to Parkinsons disease. The mechanism of action of Mn is not completely understood and thought due to decreasing dopamine levels in brain, effecting dopamine receptor activity and producing oxidative stress to mitochondria. Previously, we showed Mn caused a dose dependent decrease in mitochondrial 02 consumption, and p-aminosalicylic acid (PAS), a drug which alleviate symptoms of Manganism, protected mitochondria against Mn. PAS has anti-inflammatory and chelating abilities. The ability of PAS to ameliorate symptoms of Manganism is thought to be related to its chelating actions. To test this we studied effects of 2 chelating agents, calcium disodium EDTA (EDTAca) and diaminocyclohexanetetraacetic acid (DACH) on mitochondrial respiration the bivalve mollusc, Crassostrea viginica, using a YSI Micro-Biological Oxygen Monitor with a micro-batch chambers. Mn (5 μM – 5 mM) caused dose dependent decreases in respiration. Pretreating mitochondria with 1 mM EDTAca blocked the effects of Mn. Adding EDTAca to Mn treated mitochondria partially reversed the effects of Mn. DACH was not effective in blocking or reversing actions of Mn, and had its own inhibitory effects on respiration. The study shows EDTAca was an effective blocker against the effects of Mn and may be beneficial in reversing the negative effects of Mn accumulations. It also provides evidence the ameliorating effects of PAS on Manganism is likely related to its chelating actions. This work was supported by grants 2R25GM06003-05 of the Bridge Program of NIGMS, 0516041071 of NYSDOE and 0622197 of the DUE Program of NSF.
