Ethane exhalation and vitamin E/ubiquinol status as markers of lipid peroxidation in ferrocene iron—loaded rats

Abstract

Organ damage caused by iron overload has been mostly attributed to iron-induced peroxidation of membrane lipids. Using the ferrocene iron-loaded rat model, we studied ethane exhalation as a direct marker of in vivo lipid peroxidation, as well as concentrations of alpha-tocopherol and ubiquinol 9/10 in liver and plasma as indirect markers of this process. The feeding of a diet enriched with 0.5% TMH-ferrocene up to 31 weeks resulted in a large increase in liver iron concentration to about 25 mg/g wet weight (w wt). At lower, predominantly hepatocellular liver siderosis, the breath ethane exhalation was dependent on dietary vitamin E (VitE) supplements (onset of ethane exhalation at liver-Fe > 2 mg/g w wt on vitE-restricted diet; > 5 mg Fe per gram on VitE-replete diet). At severe liver siderosis, breath ethane exhalation reached a maximum of approximately 8 nmol/kg/hr independent of VitE supplementation. Plasma as well as hepatic alpha-tocopherol decreased with progressive iron loading. In addition, a significant depletion in hepatic ubiquinol 9 and 10 was noted.

Polyenylphosphatidylcholine Protects Against Alcohol but Not Iron‐Induced Oxidative Stress in the Liver

“…Plasma and hepatic vitamin E decreased with progressive iron loading (Dresow et al, 1995). There is no consensus on how iron overload (with or without ethanol) influences hepatic vitamin E, but our results are in good agreement with those of others (Brown et al, 1997).…”

Non-transferrin-bound iron in plasma following administration of oral iron drugs

“…That a single oral dose of vitamin E attenuates lipid peroxidation in patients on haemodialysis receiving intravenous iron was demonstrated recently (Roob et al 2000). The protecting role of vitamin E in iron induced lipid peroxidation in-vivo has also clearly been demonstrated (Dresow et al 1995).…”

Mechanism of protective effects of Danshen against iron overload-induced injury in mice

“…The liver is the major organ responsible for iron metabolism, and it is therefore the most vulnerable to serious toxicity due to iron deposition (Nielsen et al, 1993;Dresow et al, 1995). Indeed, liver coefficients were previously found to be increased in the rat liver iron overload model .…”

“…The excess iron deposition in hepatic parenchymal cells is associated with hepatic injury, fibrosis and ultimately cirrhosis (Powell et al, 1980), and lipid peroxidation has been proposed to be a major mechanism involved in the pathophysiology of hepatic iron overload (Dresow et al, 1995;Valerio and Petersen, 1998). It has also been suggested that iron facilitates the generation of free radicals, which promotes lipid peroxidation, and that this is a significant pathway for damage in carbonyl iron loaded rats Bacon et al, 1986).…”