Improved method of plasma 8-Isoprostane measurement and association analyses with habitual drinking and smoking

Figure 1 Flow chart of the improved ELISA for plasma 8-isoprostane.

Figure 2 Results of the second extraction step using an NH₂ Sep-Pac column to isolate the plasma 8-isoprostane. Spiked plasma samples containing ³H-labeled 8-isoprostane, PGF2α, TXB2, 6-keto-PGF1, PGE2 or PGD2 were used. Samples extracted with ODS gel were used to assess the absorption by, washing and elution from the NH₂ Sep-Pac column.

Figure 3 Dilution curves of plasma 8-isoprostane in 3 different plasma samples ( ▲ y = 227. 6x-2.34, r = 0.999; ■ y = 126.3x + 0.06, r = 1.000; ◆ y = 21.8x-0.04, r = 0.999).

Figure 4 Changes in AST, ALT, γ-GTP and plasma 8-isoprostane after alcohol intake. The levels of plasma 8-isoprostane in the 3 individuals increase significantly on d 1 after drinking, but return to their original levels on d 2. No significant changes are observed in AST, ALT and γ-GTP.

Figure 5 Effect of smoking habit on plasma 8-isoprostane levels. The levels of plasma 8-isoprostane were not significantly different between non smokers and smokers (21.5 ± 7.3 vs 22.8 ± 7.4 ng/L).