Mn. Nanjee et al., DO DIETARY PHYTOCHEMICALS WITH CYTOCHROME-P-450 ENZYME-INDUCING ACTIVITY INCREASE HIGH-DENSITY-LIPOPROTEIN CONCENTRATIONS IN HUMANS, The American journal of clinical nutrition, 64(5), 1996, pp. 706-711
Low plasma concentrations of high-density lipoprotein (HDL) are associ
ated with increased risk of coronary heart disease. Several drugs that
induce the microsomal cytochrome P-450-dependent enzyme system in liv
er and intestine, the sites of HDL apolipoprotein (apo) A-I and A-II s
ynthesis, raise plasma HDL concentrations in humans. To test the hypot
hesis that phytochemicals with cytochrome P-450-inducing activity may
also increase plasma HDL concentrations, two controlled dietary trials
were undertaken in healthy nonsmoking males aged 20-28 y. One study e
xamined the effect of replacing 300 g glucosinolate-free vegetables wi
th 300 g Brussels sprouts/d for 3 wk. The other study examined the eff
ects of 150 mg eugenol/d in capsule form, using a double-blind, placeb
o-controlled crossover design. There were no significant increases in
plasma apo A-I, apo A-II, HDL cholesterol, or HDL phospholipids. There
results suggest that dietary phytochemicals that induce members of th
e cytochrome P-450 system do not necessarily raise plasma HDL concentr
ations in humans, but do not exclude the possibility that some phytoch
emicals may have such an effect.