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The Oxidative State of LDL is the Major Determinant of Anti/Prooxidant Effect of Coffee on Cu Catalysed Peroxidation.

Carru C, Pasciu V, Sotgia S, Zinellu A, Nicoli MC, Deiana L, Tadolini B, Sanna B, Masala B, Pintus G - Open Biochem J (2011)

Bottom Line: When the relative effects of different coffee concentrations were plotted against the lag time (LT) of control LDL (C-LDL), the apparently random experimental data arranged in sensible patterns: by increasing the LT the antioxidant activity of coffee decreased progressively to become prooxidant.The dependence of coffee effect on the LT of C-LDL was influenced by LDL but not by metal catalyst concentration.These novel findings point to the oxidative state of LDL as a major parameter controlling the anti/prooxidant effect of coffee and suggest the LT of C-LDL as a potent analytical tool to express experimental data when studying the action exerted by a compound on LDL oxidation.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomedical Sciences, University of Sassari, Viale San Pietro 43/B, 07100 Sassari, Italy.

ABSTRACT
Antioxidants exert contrasting effect on low density lipoprotein (LDL) oxidation catalysed by metals, acting as pro-oxidants under select in vitro conditions. Through our study on the effect of coffee on LDL oxidation, we identified the parameters governing this phenomenon, contributing to the comprehension of its mechanism and discovering significant implications for correct alimentary recommendations. By measuring conjugated diene formation, we have analysed the quantitative and qualitative effects exerted by an extract of roasted coffee on LDL oxidation triggered by copper sulphate. When the relative effects of different coffee concentrations were plotted against the lag time (LT) of control LDL (C-LDL), the apparently random experimental data arranged in sensible patterns: by increasing the LT the antioxidant activity of coffee decreased progressively to become prooxidant. The critical LT, at which coffee switches from antioxidant to prooxidant, increased by increasing coffee concentration. Also the contrasting results obtained following a delayed addition of coffee to the assay, arranged in a simple pattern when referred to the LT of C-LDL: the prooxidant effect decreased to become antioxidant as the LT of C-LDL increased. The dependence of coffee effect on the LT of C-LDL was influenced by LDL but not by metal catalyst concentration. These novel findings point to the oxidative state of LDL as a major parameter controlling the anti/prooxidant effect of coffee and suggest the LT of C-LDL as a potent analytical tool to express experimental data when studying the action exerted by a compound on LDL oxidation.

No MeSH data available.


Related in: MedlinePlus

LDL (80 µg cholesterol) from a single donor was incubated either without metal catalyst (line A) in the presence of 1 µg coffee (line B) or with 1 µM copper sulphate in the absence (line C) or presence of different amounts of a coffee solution (line D 0.5 µg, line E 1 µg, line F 2 µg and line G 4 µg of coffee per assay). LDL oxidation was followed by monitoring the change of the conjugated diene absorbance at 234 nm.
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Figure 1: LDL (80 µg cholesterol) from a single donor was incubated either without metal catalyst (line A) in the presence of 1 µg coffee (line B) or with 1 µM copper sulphate in the absence (line C) or presence of different amounts of a coffee solution (line D 0.5 µg, line E 1 µg, line F 2 µg and line G 4 µg of coffee per assay). LDL oxidation was followed by monitoring the change of the conjugated diene absorbance at 234 nm.

Mentions: First we evaluated the influence exerted on LDL oxidation, triggered by 1 µM copper, by variable amounts of a coffee solution. The results reported in Fig. (1) show that different coffee concentrations may exert either an antioxidant or a prooxidant effect, in particular the lower concentrations tested were pro-oxidant whereas the highest was antioxidant.


The Oxidative State of LDL is the Major Determinant of Anti/Prooxidant Effect of Coffee on Cu Catalysed Peroxidation.

Carru C, Pasciu V, Sotgia S, Zinellu A, Nicoli MC, Deiana L, Tadolini B, Sanna B, Masala B, Pintus G - Open Biochem J (2011)

LDL (80 µg cholesterol) from a single donor was incubated either without metal catalyst (line A) in the presence of 1 µg coffee (line B) or with 1 µM copper sulphate in the absence (line C) or presence of different amounts of a coffee solution (line D 0.5 µg, line E 1 µg, line F 2 µg and line G 4 µg of coffee per assay). LDL oxidation was followed by monitoring the change of the conjugated diene absorbance at 234 nm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3104561&req=5

Figure 1: LDL (80 µg cholesterol) from a single donor was incubated either without metal catalyst (line A) in the presence of 1 µg coffee (line B) or with 1 µM copper sulphate in the absence (line C) or presence of different amounts of a coffee solution (line D 0.5 µg, line E 1 µg, line F 2 µg and line G 4 µg of coffee per assay). LDL oxidation was followed by monitoring the change of the conjugated diene absorbance at 234 nm.
Mentions: First we evaluated the influence exerted on LDL oxidation, triggered by 1 µM copper, by variable amounts of a coffee solution. The results reported in Fig. (1) show that different coffee concentrations may exert either an antioxidant or a prooxidant effect, in particular the lower concentrations tested were pro-oxidant whereas the highest was antioxidant.

Bottom Line: When the relative effects of different coffee concentrations were plotted against the lag time (LT) of control LDL (C-LDL), the apparently random experimental data arranged in sensible patterns: by increasing the LT the antioxidant activity of coffee decreased progressively to become prooxidant.The dependence of coffee effect on the LT of C-LDL was influenced by LDL but not by metal catalyst concentration.These novel findings point to the oxidative state of LDL as a major parameter controlling the anti/prooxidant effect of coffee and suggest the LT of C-LDL as a potent analytical tool to express experimental data when studying the action exerted by a compound on LDL oxidation.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomedical Sciences, University of Sassari, Viale San Pietro 43/B, 07100 Sassari, Italy.

ABSTRACT
Antioxidants exert contrasting effect on low density lipoprotein (LDL) oxidation catalysed by metals, acting as pro-oxidants under select in vitro conditions. Through our study on the effect of coffee on LDL oxidation, we identified the parameters governing this phenomenon, contributing to the comprehension of its mechanism and discovering significant implications for correct alimentary recommendations. By measuring conjugated diene formation, we have analysed the quantitative and qualitative effects exerted by an extract of roasted coffee on LDL oxidation triggered by copper sulphate. When the relative effects of different coffee concentrations were plotted against the lag time (LT) of control LDL (C-LDL), the apparently random experimental data arranged in sensible patterns: by increasing the LT the antioxidant activity of coffee decreased progressively to become prooxidant. The critical LT, at which coffee switches from antioxidant to prooxidant, increased by increasing coffee concentration. Also the contrasting results obtained following a delayed addition of coffee to the assay, arranged in a simple pattern when referred to the LT of C-LDL: the prooxidant effect decreased to become antioxidant as the LT of C-LDL increased. The dependence of coffee effect on the LT of C-LDL was influenced by LDL but not by metal catalyst concentration. These novel findings point to the oxidative state of LDL as a major parameter controlling the anti/prooxidant effect of coffee and suggest the LT of C-LDL as a potent analytical tool to express experimental data when studying the action exerted by a compound on LDL oxidation.

No MeSH data available.


Related in: MedlinePlus