Parkinson's disease (PD) is the second most prevalent age-related neurodegenerative disease with physiological manifestations including tremors, bradykinesia, abnormal postural reflexes, rigidity and akinesia and pathological landmarks showing losses of dopaminergic neurons in the substantia nigra. Although the etiology of PD has been intensively pursued for several decades, biochemical mechanisms and genetic and epigenetic factors leading to initiation and progression of the disease remain elusive. Environmental toxins including (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) MPTP, paraquat and rotenone have been shown to increase the risk of PD in humans. Oxidative stress remains the leading theory for explaining progression of PD. Studies with cell and animal models reveal oxidative and inflammatory properties of these toxins and their ability to activate glial cells which subsequently destroy neighboring dopaminergic neurons. This review describes pathological effects of neurotoxins on cells and signaling pathways for production of reactive oxygen species (ROS) that underline the pathophysiology of PD.

Defining intracellular protein concentration is critical in molecular systems biology. Although strategies for determining relative protein changes are available, defining robust absolute values in copies per cell has proven significantly more challenging. Here we present a reference data set quantifying over 1800 Saccharomyces cerevisiae proteins by direct means using protein-specific stable-isotope labeled internal standards and selected reaction monitoring (SRM) mass spectrometry, far exceeding any previous study. This was achieved by careful design of over 100 QconCAT recombinant proteins as standards, defining 1167 proteins in terms of copies per cell and upper limits on a further 668, with robust CVs routinely less than 20%. The selected reaction monitoring-derived proteome is compared with existing quantitative data sets, highlighting the disparities between methodologies. Coupled with a quantification of the transcriptome by RNA-seq taken from the same cells, these data support revised estimates of several fundamental molecular parameters: a total protein count of ∼100 million molecules-per-cell, a median of ∼1000 proteins-per-transcript, and a linear model of protein translation explaining 70% of the variance in translation rate. This work contributes a “gold-standard” reference yeast proteome (including 532 values based on high quality, dual peptide quantification) that can be widely used in systems models and for other comparative studies.

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Plant polyphenols are dietary components that exert a variety of biochemical and pharmacological effects. Recently, considerable interest has been focused on polyphenols because of their antioxidant, anti-inflammatory, and antiproliferative activities. Oxidative stress is thought to be a key event in the pathogenesis of cerebral ischemia. Overproduction of reactive oxygen species during ischemia/reperfusion could cause an imbalance between oxidative and antioxidative processes. Reactive oxygen species can damage lipids, proteins, and nucleic acids, thereby inducing apoptosis or necrosis. There is increasing evidence supporting the hypothesis that plant polyphenols can provide protection against neurodegenerative changes associated with cerebral ischemia. This article reviews the neuroprotective effects of plant extracts and their constituents that have been used in animal models of cerebral ischemia. The use of polyphenols as therapeutic agents in stroke has been suggested.

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