Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:1.12.7.2 (
hydrogenase
)
3,522
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Albumin induces oxidative stress and cytokine production in proximal tubular cells (PTECs). Albumin-bound fatty acids (FAs) enhance tubulopathic effects of albumin in vivo. We proposed that FA aggravation of albumin-induced oxidative stress in PTECs might be involved. We hypothesized that mitochondria could be a source of such stress. Using a fluorescent probe, we compared reactive oxygen species (ROS) production after exposure of PTECs to bovine serum albumin (BSA) alone or loaded with oleic acid (OA-BSA) (3-30 g/l for 2 h). There was no difference in cellular albumin uptake, but OA-BSA dose-dependently induced more ROS than BSA alone (P<0.001). OA-BSA-induced ROS was significantly alleviated by mitochondrial inhibition, but not by inhibitors of nicotinamide adenine dinucleotide phosphate
hydrogenase
(NADPH) oxidase, xanthine oxidase, or
nitric oxide synthase
. Gene expression analysis showed that neither the NADPH oxidase component p22phox nor xanthine oxidase was induced by BSA or OA-BSA. OA-BSA, in contrast to BSA, failed to induce mitochondrial manganese superoxide dismutase 2 (SOD2) expression. OA-BSA showed a greater capacity than BSA to downregulate heme oxygenase-1 mRNA expression and accentuate inflammatory cytokine mRNA and protein. Supplementation of SOD activity with EUK-8 reduced ROS, and interleukin-6 protein expression was suppressed by both mitochondrial inhibition and SOD augmentation. Thus, in PTECs, FAs accentuate albumin-induced oxidative stress and inflammatory cytokine expression via increased mitochondrial ROS, while frustrating protective antioxidant responses.
...
PMID:Albumin-bound fatty acids induce mitochondrial oxidant stress and impair antioxidant responses in proximal tubular cells. 1683 28
The guanidine moiety of arginine is involved in the active sites of a variety of enzymes, such as
nitric oxide synthase
(
NOS
) and NiFe
hydrogenase
. In this paper we aim to investigate the effects of a metal center on the oxidation of guanidine, which should provide an interesting comparison with the biological aerobic oxidation of arginine catalyzed by
NOS
. We studied the oxidation of an osmium(III) guanidine complex, mer-[Os(L){N(H)C(NH
2
)
2
}(CN)
3
]
-
, (OsG, HL = 2-(2-hydroxyphenyl)benzoxazole) by m-chloroperbenzoic acid (m-CPBA), which is potentially an O atom transfer reagent, and by (NH
4
)
2
[Ce
IV
(NO
3
)
6
], which is a one-electron oxidant. With m-CPBA, mer-[Os(NO)(L)(CN)
3
]
-
(mer-OsNO) is the product, while with Ce
IV
, mer-[Os
VI
(N)(L)(CN)
3
]
-
(mer-OsN) is formed instead. The crystal structures of mer-OsNO and mer-OsN were determined by X-ray crystallography. The mechanisms for the oxidation of OsG by m-CPBA and Ce
IV
are proposed.
...
PMID:Dual Pathways in the Oxidation of an Osmium(III) Guanidine Complex. Formation of Osmium(VI) Nitrido and Osmium Nitrosyl Complex. 2814 May 72
