Parkinson's disease (PD) is currently the second most common
neurodegenerative disorder in the world. Major features of cell
pathology of the disease include the presence of cytoplasmic
inclusions called Lewy bodies, which are composed of aggregated
proteins. The presence of Lewy's body is associated with more
advanced stages of the disease when considering irreversible
changes. Precise identification of the disease stage at a cellular
level presents the critical tool in developing early diagnostics
and/or prevention of PD. The aim of our work is to introduce
sensitive microscopic analysis in living cells, focused on initial
intracellular changes and thus capable to detect earlier stages of
the disease.
Kinetics of non-photochemical reduction of the photosynthetic intersystem electron transport chain by exogenous NADPH was examined in osmotically lysed spinach chloroplasts by chlorophyll (Chl) fluorescence measurements under anaerobic condition. Upon the addition of NADPH, the apparent F0 increased sigmoidally, and the value of the maximal slope was calculated to give the reduction rate of plastoquinone (PQ) pool. Application of 5 µM antimycin A lowered significantly both the ceiling and the rate of the NADPH-induced Chl fluorescence increase, while the suppressive effect of 10 µM rotenone was slighter. This indicated that dark reduction of the PQ pool by NADPH in spinach chloroplasts under O2-limitation condition could be attributed mainly to the pathway catalysed sequentially by ferredoxin-NADP+ oxidoreductase (FNR) and ferredoxin-plastoquinone reductase (FQR), rather than that mediated by NAD(P)H dehydro-genase (NDH). and Ming-Xian Jin, Hualing Mi.