Cystinosis is a lysosomal storage disorder characterized by abnormal accumulation of cystine, which forms crystals at high concentrations. The causative gene CTNS encodes cystinosin, the lysosomal cystine transporter. The eye is one of the first organs affected (corneal lesions and photophobia in the first and visual impairment in the second decade of life).
View Article and Find Full Text PDFElectron paramagnetic resonance (EPR) spin trapping studies demonstrated aqueous tar particulate matter (TPM) and gas phase cigarette smoke (GPCS) to behave as different sources of free radicals in cigarette smoke (CS) but their cytotoxic implications have been only assessed in CS due to its relevance to the natural smoking process. Using a sensitive spin trapping detection with 5-(diethoxyphosphoryl)-5-methyl-1-pyrroline-N-oxide (DEPMPO), this study compared the respective roles of CS- and GPCS-derived free radicals on smoke-induced cytotoxicity and lipid peroxidation of filtered and unfiltered, machine-smoked experimental and reference cigarettes yielding a wide range of TPM yields. In buffer bubbled with CS the DEPMPO/superoxide spin adduct was the major detected nitroxide.
View Article and Find Full Text PDFThe pharmacological and neuroprotective properties of two ester analogs of the endocannabinoids, arachidonoylethyleneglycol (AA-EG) and alpha,alpha,-dimethyl arachidonoylethyleneglycol (DMA-EG), were investigated. We examined the interaction of both compounds with cannabinoid receptors (CB1 and CB2) and their efficacy in functional assays. In competition binding assays, AA-EG and DMA-EG had low potency to displace the CB1/CB2 agonist [3H]CP-55,940 in membrane preparations expressing rodent or human receptors.
View Article and Find Full Text PDFThe purpose of this study was to investigate the mechanism of the neuroprotective activity of trimetazidine in animal retina stressed by ischemia or kainate. Flash electroretinograms were recorded in guinea pigs after ischemia, induced by an acute increase in the intraocular pressure (IOP), or after an intravitreal injection of kainate. Treatment with trimetazidine per os afforded a significant protection of the electroretinogram against the ischemic as well as the excitotoxic insult as an antioxidant (dimethylthiourea) and a nitric oxide synthase inhibitor (nitroarginine) did.
View Article and Find Full Text PDFNeurosci Lett
February 2004
Glutamate uptake in neurons and glial cells is essential to prevent the persistence of excitotoxic levels of glutamate observed during ischemia. We demonstrated that a short period of hypoxia stimulated the apparent glutamate transport rate in isolated rat retinal cells. The observed increase in glutamate uptake was not affected by glutamate receptor antagonists, protein kinase inhibitors, antioxidant or neo-synthesis inhibitors.
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