Disease relevance of ruthenium

• Electron coupling through a beta strand has been investigated by measurement of the intramolecular electron-transfer (ET) rates in ruthenium-modified derivatives of the beta barrel blue copper protein Pseudomonas aeruginosa azurin [1].
• After 5, 15, and 30 min of ischemia, however, there was a successive stepwise increase in tight junction penetration by ruthenium red to 29, 50, and 62%, respectively [2].
• Although activation of the ER stress response did not prevent toxicity due to Ca2+ influx, EGTA-AM and ruthenium red both blocked cell death suggesting that redistribution of intracellular Ca2+ to the mitochondria may be important in toxicity [3].
• Proteoglycans were identified in this material by digesting tissues with Streptomyces hyaluronidase, testicular hyaluronidase, chondroitinase ABC, or heparinase before ruthenium red staining [4].
• Electron transfer from the Rieske iron-sulfur protein to cytochrome c(1) (cyt c(1)) in the Rhodobacter sphaeroides cytochrome bc(1) complex was studied using a ruthenium dimer complex, Ru(2)D [5].

Psychiatry related information on ruthenium

• A significant (P < 0.02) 40% decrease in the Bmax for [3H]ryanodine binding and significantly higher IC50 values for both magnesium and Ruthenium Red inhibition of [3H]ryanodine binding were detected in Alzheimer's disease temporal cortex particulate fractions compared to controls [6].
• Using the chelation strategy, the reaction of aldimines bearing the 3-picolin-2-yl group with various arylboronates in the presence of a ruthenium catalyst furnished the corresponding ketimines in high yields for a short reaction time; the resulting ketimines were readily converted to ketones by hydrolysis [7].

High impact information on ruthenium

• Studies of ET reactions in ruthenium-modified proteins have probed lambda and HAB in several metalloproteins (cytochrome c, myoglobin, azurin) [8].
• Although the ruthenium-modified oligonucleotide hybridized to an unmodified complement luminesces intensely, the ruthenium-modified oligomer hybridized to the rhodium-modified oligomer shows no detectable luminescence [9].
• Unlike their wild-type counterparts, SON neurons in Trpv1 knockout (Trpv1(-/-)) mice could not generate ruthenium red-sensitive increases in membrane conductance and depolarizing potentials in response to hyperosmotic stimulation [10].
• Inactivation was partially but not completely precluded by EDTA, EGTA, magnesium, diltiazem, or ruthenium red, results in concert with findings of others suggesting involvement of a deleterious influx of calcium into mitochondria; exogenous calcium enhanced inactivation [11].
• Ruthenium red has an affinity for acid mucopolysaccharides of the cell coat [12].

Chemical compound and disease context of ruthenium

• The reaction between cytochrome c (Cc) and Rhodobacter sphaeroides cytochrome c oxidase (CcO) was studied using a cytochrome c derivative labeled with ruthenium trisbipyridine at lysine 55 (Ru-55-Cc) [13].
• This influx was sensitive to blockers of TRP-like nonspecific Ca(2+) channels, including Ruthenium Red, La(3+), and Gd(3+) ions which also prevented the Fe(2+) ion-induced toxicity and oxidative stress as revealed by protein carbonylation status [14].
• Intersubunit crosslinking was found to occur exclusively at adjacent tyrosine residues (Y52-Y103), as predicted from the X-ray crystal structure of the capsid, and to be more extensive with the photochemical ruthenium system [15].
• Capsaicin antagonists including ruthenium red, capsazepine and iodo-resiniferatoxin (I-RTX) have recently been shown to inhibit the activation by noxious heat of the capsaicin receptor (TRPV1) expressed in non-neuronal host cells, and natively, in cultured dorsal root ganglion cells [16].
• Visualization of capsules on both N. gonorrhoeae and Neisseria meningitidis with ruthenium red was not as consistent as with Alcian blue, presumably because Alcian blue-glutaraldehyde not only stains but also fixes the polysaccharide [17].

Biological context of ruthenium

• Ruthenium red, a specific inhibitor of Ca,Mg-ATPase and Ca transport, inhibited endocytosis in a concentration-related manner [18].
• Ruthenium red delays the onset of cell death during oxidative stress of rat hepatocytes [19].
• After 2 hours of oxidative stress, cell viability was greater with than without 25 mumol/L ruthenium red (37% vs. 4.6%; P less than 0.01) [19].
• Indeed, ruthenium red still improved cell survival after 2 hours of exposure to 10 mumol/L carbonyl cyanide m-chlorophenylhydrazone (CCCP), a mitochondrial uncoupler (39% vs. 13%; P less than 0.01) [19].
• In addition, independence of Con A receptors, colloidal iron binding sites, and ruthenium red-stainable surface components from membrane particles was demonstrated at the flagellar membrane [20].

Anatomical context of ruthenium

• Under control situations ruthenium red penetrated less than 10% of the tight junctions [2].
• Ruthenium red-staining coat of paired neoplastic and nonneoplastic mouse cell lines in cluture [12].
• As judged by ruthenium red staining, cup cells are comparable to absorptive cells in the density of glycocalyceal anionic sites; thus cup cells would not be expected to bind negatively charged plasma membranes (like those of bacteria) simply on the basis of having diminished negative charge of the glycocalyx [21].
• In contrast, ruthenium red did retard loss of the mitochondrial membrane potential (78% vs. 42% within 30 minutes; P less than 0.01) [19].
• Our objective was to determine if ruthenium red protects against lethal oxidative injury of rat hepatocytes. tert-Butyl hydroperoxide, 100 mumol/L, was used to produce oxidative stress [19].

Associations of ruthenium with other chemical compounds

• Ca2+ uptake was found to be dependent on time, pH, temperature, and ionic strength of the incubation medium and inhibitable by ruthenium red, La3+, and ethylene glycol-bis(beta-amino-ethyl ether)-N,N,N',N'-tetraacetic acid [22].
• The ultrastructural characteristics of alveolar (ABM) and capillary (CBM) basement membranes in the adult rat lung have been defined using tannic acid fixation, ruthenium red staining, or incubation in guanidine HCl [23].
• In cardiac and skeletal muscle these channels are called the calcium-release channel and are identified by activation with either calcium or caffeine and inhibition by the hexavalent cation ruthenium red [24].
• 45Ca2+ accumulation in the presence of the calcium efflux inhibitors, procaine (10 mM) and ruthenium red (30 microM), was used to characterize unidirectional uptake kinetics [25].
• In the presence of 25 mumol/L ruthenium red and 10 mmol/L oxalate, the Km for Ca2+ uptake by the SR was approximately 250 nmol/L in rabbit and rat ventricular myocytes [26].

Gene context of ruthenium

• Hypotonic reduction of AQP5 was observed only in the presence of TRPV4 and was blocked by ruthenium red [27].
• Similarly, addition of hypotonic PBS to mouse trachea in vivo decreased AQP5 within 1 h, an effect blocked by ruthenium red [27].
• Inhibition of both tumor and host NOS activities, with an iNOS-selective inhibitor (1400W), a nonselective NOS inhibitor [Nomega-nitro-L-arginine methyl ester (L-NAME)], or scavenging NO with a ruthenium-based scavenger, significantly delayed tumor rejection, while having no appreciable effect on tumor growth [28].
• The TRPM6-induced channel displays strong outward rectification, has a 5-fold higher affinity for Mg2+ than for Ca2+, and is blocked in a voltage-dependent manner by ruthenium red [29].
• There is a direct correlation between ADK activity and the level of methylesterified pectin in seed mucilage, as monitored by staining with ruthenium red, immunofluorescence labeling, or direct assay [30].

Analytical, diagnostic and therapeutic context of ruthenium

• The ruthenium red-staining coat (RRSC) of a pair of neoplastic and nonneoplastic cell lines derived from a common pool of mouse embryo cells was examined by electron microscopy [12].
• Amperometry at a carbon fiber microelectrode modified with a composite of ruthenium oxide and cyanoruthenate was used to monitor chemical secretions of single pancreatic beta cells from rats and humans [31].
• The site of ruthenium binding (His-83) was identified by peptide mapping [32].
• Dissociation between contractile function and oxidative metabolism in postischemic myocardium. Attenuation by ruthenium red administered during reperfusion [33].
• Since the Ca2+ uptake in the presence of ryanodine or ruthenium red is determined by the Ca(2+)-ATPase, this result suggests that perfusion with varying [Ca2+] did not affect the Ca(2+)-ATPase [34].

References