A clinic-based cohort study in Kampala, Uganda, was conducted to examine the relationship between severe malarial anaemia and plasma micronutrients. Plasma carotenoids, retinol, vitamin E, and four trace metal concentrations were measured at enrollment and seven days later in 273 children, aged 1-10 year(s), with acute, uncomplicated Plasmodium falciparum malaria. Concentrations of plasma provitamin A carotenoids (p < 0.0001), non-provitamin A carotenoids (p < 0.0001), retinol (p < 0.0001), all four trace elements (all p < 0.001), and vitamin E (p < 0.0001) rose significantly by day 7 among children without severe anaemia (haemoglobin 70 g/L). There was no change in provitamin A carotenoids (p = 0.24) among children with severe anaemia (haemoglobin <70 g/L), whereas non-provitaminAcarotenoids (p < 0.0001), retinol (p < 0.0001), and vitamin E (p = 0.011) increased. These observations also support the hypothesis that the use of provitamin A carotenoids increases during malaria infection.

Breast milk vitamin A is not well characterized as an indicator of vitamin A status in women with infections. A controlled trial of vitamin A, 3 mg retinol equivalent/day, was conducted among 697 pregnant women with human immunodeficiency virus (HIV) infection in Malawi which allowed comparison of plasma versus breast milk vitamin A as indicators of vitamin A status. Retinol concentrations were measured in plasma at baseline (18-28 weeks) and 38 weeks gestation and breast milk at 6 weeks post-partum. Plasma alpha 1-acid glycoprotein (AGP) and C-reactive protein (CRP) were measured at baseline. Plasma retinol (geometric mean, SD) at 38 weeks was 0.72 (0.44, 1.18) and 0.61 (0.38, 0.98) mumol/L (P < 0.0002) and breast milk retinol was 1.32 (0.71, 2.43) and 0.95 (0.49, 1.82) mumol/L (P < 0.0001) in vitamin A and placebo groups, respectively. Women with elevated acute phase protein (AGP > 1 gm/L and/or CRP > 5 mg/L) at baseline who received vitamin A had significantly higher plasma and breast milk vitamin A at follow-up compared with placebo. Elevated acute phase proteins did not distinguish women with low body stores of vitamin A. Breast milk retinol appears to be a better indicator of vitamin A status than plasma retinol in women with infections.

Leukotrienes (LTs), the 5-lipoxygenase (5-LOX) metabolites of arachidonic acid, have roles in many biological processes relevant to the gastrointestinal tract, including intestinal inflammation. We screened two well-known human intestinal epithelial cell lines, HT29 and Caco-2, for evidence of LT-associated enzyme transcripts and LT synthesis. Northern blot analysis of total RNA from both intestinal lines demonstrated high levels of transcripts for LTA4 hydrolase, a multisubstrate enzyme that converts the 5-LOX metabolite, LTA4, to LTB4. With total RNA, the 5-LOX transcript was detected only in HT29. Caco-2 failed to show 5-LOX message even with poly A-containing RNA, although the transcript could be amplified with the polymerase chain reaction. Messenger RNA for FLAP, the 5-lipoxygenase-activating protein, was detectable in both cell lines, but only with poly A-containing RNA. In a sonicated cell preparation, HT29, but not Caco-2, revealed detectable levels of 5-HETE and LTB4. These results suggest that certain intestinal epithelial cells possess a limited capacity to synthesize LTs.