In C2C12 myotubes and in mouse muscle, mutant constitutively activated STAT3-induced muscle fiber atrophy and exacerbated wasting in cachexia. Conversely, inhibiting STAT3 pharmacologically with JAK or STAT3 inhibitors or
genetically with dominant negative STAT3 and short hairpin STAT3 reduced muscle atrophy downstream of IL-6 or cancer. These results indicate that STAT3 is a primary mediator of muscle wasting in cancer cachexia and other conditions of high IL-6 family signaling. Thus STAT3 could represent a novel therapeutic target for the preservation of skeletal muscle in cachexia.”
“Diphenyl diselenide [(PhSe)(2)], an organoselenium compound, presents toxicological effects in rat pups, manifested by the appearance of seizure episodes. The aim of this study was to carry out the determination and quantification of (PhSe)(2) in plasma, liver and brain of rat pups after oral administration (p.o) Stem Cell Compound Library concentration of this compound (500 mg/kg).
The second objective of this study was to correlate the latency to the appearance for the first seizure episode with (PhSe)(2) plasma, liver and brain levels. Analysis of (PhSe)(2) in plasma, liver and brain samples was performed by gas chromatography/flame ionized detector system (GC/FID). The average levels of (PhSe)(2) in plasma, liver and brain of rat pups were 3.67, 5.07 and Cl-amidine research buy 1.15 mu g/ml, respectively, at 20.58 min post dosing, the latency media for the first seizure episode. (PhSe)(2) levels in plasma did not correlate with the latency for the first seizure episode induced by this compound. A significant negative correlation between the latency for the first seizure episode and the levels of (PhSe)(2) liver and brain of rat pups was found. It demonstrates that rat pups which R406 had highest levels of (PhSe)(2) in liver and brain showed the shortest latency for the first seizure episode.”
“In inside-out bovine heart sarcolemmal vesicles, p-chloromercuribenzenesulfonate (PCMBS) and n-ethylmaleimide (NEM) fully inhibited MgATP up-regulation of the
Na+/Ca2+ exchanger (NCX1) and abolished the MgATP-dependent PtdIns-4,5P2 increase in the NCX1-PtdIns-4,5P2 complex; in addition, these compounds markedly reduced the activity of the PtdIns(4)-5kinase. After PCMBS or NEM treatment, addition of dithiothreitol (DTT) restored a large fraction of the MgATP stimulation of the exchange fluxes and almost fully restored PtdIns(4)-5kinase activity; however, in contrast to PCMBS, the effects of NEM did not seem related to the alkylation of protein SH groups. By itself DTT had no effect on the synthesis of PtdIns-4,5P2 but affected MgATP stimulation of NCX1: moderate inhibition at 1 mM MgATP and 1 mu M Ca2+ and full inhibition at 0.25 mM MgATP and 0.2 mu M Ca2+. In addition, DDT prevented coimmunoprecipitation of NCX1 and PtdIns(4)-5kinase.