On the Characteristics of the Visible Chemiluminescence Following Free Radical Lipid Peroxidation

Abstract

The characteristics of the visible luminescence that follows the lipid peroxidative process were investigated either in the autoxidation of rat brain homogenates or in the azo-bis-amidinopropane initiated lipid peroxidation of erythrocyte plasma membranes and liver microsomes. In these systems the luminescence decay observed after total inhibition of the lipid peroxidation is not an iron-catalyzed process, and follows a complex kinetics comprising fast and slow components. The slow component of the decay lasts for several hours at 27 degrees C and amounts to nearly half of the total intensity measured prior to the inhibition of the oxidative process by propyl gallate. The addition of thiols (diethyldithiocarbamate, penicillamine or dithiothreitol) to a lipid peroxidizing system inhibits the chain oxidation and catalyzes the dark decomposition of one (or several) of the luminescence precursors, following first order kinetics. The effect of temperature on the slow luminescence decay corresponds to an activation energy of 18.5 kcal/mol.

Antioxidant and pro-oxidant effects of red wine and its fractions on Cu(II) induced LDL oxidation evaluated by absorbance and chemiluminescence measurements

“…This decrease is nearly, independent, of the additive concentration (micromolar range, data not shown), and is similar to that observed in the oxidation of biological samples, ranging from homogenates to purified proteins [59 -61]. This behavior has been considered as evidence that the CL arises mainly from the decomposition of preformed peroxides, and not from a Russel's like process [59]. In order to test this hypothesis, ebselen, a compound efficient in hydroperoxide removal, was added to the sample after its extensive oxidation.…”

“…CuðIÞ þ PhO* þ H þ CuðIÞ þ LOOH ! CuðIIÞ þ LO* þ HO 2 followed by the CL emitted through the secondary reactions of the PhO* and/or LO* radicals [59][60][61]64]. The addition of EDTA ( Figure 9) and DFO (in a smaller extent, data not shown) would reduce the rate of these processes as a consequence of their chelating capacity.…”

“…The longer lag time is due to the lower temperature employed in the CL experiments. However, it must be considered that, while the absorbance is directly related to product formation, the CL is a rate whose intensity must be related to the concentration of the emitting species [59][60]. It is interesting to note that the light intensity remains high for a long time, suggesting that CL is being emitted under conditions, where the formation of LDL oxidized products, measured by absorbance changes, is negligible.…”

p,p’-DDT induces testicular oxidative stress-induced apoptosis in adult rats

“…The increase of hydrogen peroxide levels may be due to reduced SOD and CAT activities in testis. This condition could be favorable to hydroxyl radical formation which may lead to lipid peroxidation [43]. Besides, SOD is known to catalyse the dismutation of superoxide anions to H 2 O 2 and molecular oxygen, while CAT has been shown to be responsible for the detoxification of H 2 O 2 [44].…”

Antioxidative stress therapy with dithiothreitol tetraacetate I. Protection against carbon tetrachloride induced liver necrosis

“…Previous studies from other laboratories using different LP promoting systems and other procedures for its detection alternatively reported DTT either as an LP inhibitor or as an enhancer. This is not unexpected (Kamitaki et al 1977;Heanen et al 1989;Lissi et al 1989;Zimmerman and Kays 1991) for several thiol-containing molecules exhibit biphasic properties leading to either inhibitory or promoting properties according to used concentration and other characteristics of the experimental system employed (Held and Melder 1987;Munday 1989). The LP promoting effects were related to its ability to produce oxygen activated species such as 02 and OH radicals (Munday 1989).…”