2% tween20. After an incubation on ice for 15 min, fetal calf serum was added in a 1 50 dilution for blocking. U0126 supplier The cells were incubated for 2 h on ice with a MAP2 anti body and washed three times with 0. 1% tween20. Following an incubation for 30 min on ice with a donkey anti mouse FITC conjugated secondary anti body, Inhibitors,Modulators,Libraries the cells were washed again three times with 0. 1% tween20, and finally resuspended in 1�� PBS for FACS analysis. Flow cytometry of cells was performed on a FACSCalibur. Background Maternally inherited mitochondrial DNA codes for several mitochondrial proteins, primarily components of the mitochondrial electron transport chain. Point mutations in mtDNA are causes of several diseases, including mitochondrial encephalomyopathy with lactic acidosis and stroke like episodes, neuropathy, ataxia, and retinitis pigmentosa, and Lebers hereditary optic neu ropathy.
LHON is the most common hereditary optic nerve disease causing severe visual loss. Most Inhibitors,Modulators,Libraries primary mutations code for proteins in METC complex I, although some secondary mutations are in complex III. A fundamental paradox of diseases caused by mtDNA point mutations is that although all mitochondria in the body have the same mutation, the disease is usually expressed in a restricted number of tissues. In the case of LHON, the Inhibitors,Modulators,Libraries disease is almost exclusively manifested in ret inal ganglion cells, the axons of which make up the optic nerve. The reason for this cell type specificity is unknown, but presumably is related to a particular sus ceptibility of RGCs to a consequence of these mutations.
The effect of LHON mutations has been studied by pro ducing transmitochondrial cybrids in human cell lines, demonstrating upregulation of some mtDNA transcripts, e. g. aldose reductase. LHON cybrids forced to use the METC as their primary energy source by plating on glu cose deficient galactose media, experience apoptotic death and increased cytochrome c release. Common Inhibitors,Modulators,Libraries LHON mutations reduce the rate of respiration in LHON cybrids and oxygen consumption. Most importantly, LHON cybrids have increased superoxide production compared to wild type cells. Given that METC complexes I and III are the main Inhibitors,Modulators,Libraries sources of basal superoxide production, it is possible that aberrant production of superoxide from mutated METC components would cause cell death.
But why would abnormalities in superoxide production be a mechanism for the relatively specific effect of LHON mtDNA muta tions on RGCs One explanation is the finding that RGCs use superoxide as an intracellular signal for initiating the http://www.selleckchem.com/products/Imatinib(STI571).html apoptosis program after apoptosis, probably by oxidizing critical sulfhydryls in signaling macromolecules. Supporting this theory, RGC death is triggered when mitochondrial superoxide levels are increased by knocking down mitochondrial superoxide dismutase.