A Western dietary pattern at 14 years in a general population sample was associated with an increased risk of NAFLD at 17 years, particularly in obese adolescents. In centrally obese adolescents with NAFLD, a healthy dietary pattern may be protective, whereas a Western dietary pattern may increase the risk.

The liver plays a central role in iron metabolism. It is the major storage site for iron and also expresses a complex range of molecules which are involved in iron transport and regulation of iron homeostasis. An increasing number of genes associated with hepatic iron transport or regulation have been identified. These include transferrin receptors (TFR1 and 2), a ferrireductase (STEAP3), the transporters divalent metal transporter-1 (DMT1) and ferroportin (FPN) as well as the haemochromatosis protein, HFE and haemojuvelin (HJV), which are signalling molecules. Many of these genes also participate in iron regulatory pathways which focus on the hepatic peptide hepcidin. However, we are still only beginning to understand the complex interactions between liver iron transport and iron homeostasis. This review outlines our current knowledge of molecules of iron metabolism and their roles in iron transport and regulation of iron homeostasis.

Iron and cholesterol are both essential metabolites in mammalian systems, and too much or too little of either can have serious clinical consequences. In addition, both have been associated with steatosis and its progression, contributing, inter alia, to an increase in hepatic oxidative stress. The interaction between iron and cholesterol is unclear, with no consistent evidence emerging with respect to changes in plasma cholesterol on the basis of iron status. We sought to clarify the role of iron in lipid metabolism by studying the effects of iron status on hepatic cholesterol synthesis in mice with differing iron status. Transcripts of seven enzymes in the cholesterol biosynthesis pathway were significantly upregulated with increasing hepatic iron (R 2 between 0.602 and 0.164), including those of the rate-limiting enzyme, 3-hydroxy-3-methylglutarate-coenzyme A reductase (Hmgcr; R 2 5 0.362, P < 0.002). Hepatic cholesterol content correlated positively with hepatic iron (R 2 5 0.255, P < 0.007). There was no significant relationship between plasma cholesterol and either hepatic cholesterol or iron (R 2 5 0.101 and 0.014, respectively). Hepatic iron did not correlate with a number of known regulators of cholesterol synthesis, including sterol-regulatory element binding factor 2 (Srebf2; R 2 5 0.015), suggesting that the increases seen in the cholesterol biosynthesis pathway are independent of Srebf2. Transcripts of genes involved in bile acid synthesis, transport, or regulation did not increase with increasing hepatic iron. Conclusion: This study suggests that hepatic iron loading increases liver cholesterol synthesis and provides a new and potentially important additional mechanism by which iron could contribute to the development of fatty liver disease or lipotoxicity. (HEPATOLOGY 2010;52:462-471) Abbreviations: Abc, adenosine triphosphate-binding cassette; Apo, apolipoprotein; Bhmt2, betaine-homocysteine methyltransferase 2; C/EBPa, CCAAT/enhancer binding protein a; Cyp51, lanosterol-14a demethylase; Cyp27b1, 25-hydroxyvitamin D3-1a-hydroxylase; Cyp7a1, cholesterol 7a-monooxygenase; Ebp, cholestenol-D-isomerase; Ggcx, gamma-glutamyl carboxylase; Ggps1, geranylgeranyl diphosphate synthase 1; GSEA, gene set enrichment analysis; Hmgcr, 3-hydroxy-3-methylglutarate-coenzymeA reductase; Hnf4a, hepatocyte nuclear factor 4a; Hsd17b7, 3-keto-steroid reductase; Hsd3b7, hydroxy-D5-steroid dehydrogenase; Idi1, isopentenyl-diphosphate-D-isomerase; mRNA, messenger RNA; Mvk, mevalonate kinase; NAFLD, nonalcoholic fatty liver disease; NASH, nonalcoholic steatohepatitis; Nqo1, NAD(P)H dehydrogenase (quinone) 1; Nr1h3, nuclear receptor 1H3; Nsdhl, sterol-4a-carboxylate 3-dehydrogenase; Pmvk, phosphomevalonate kinase; Psap, prosaponin; RT-PCR, real-time polymerase chain reaction; Sc5d, lathosterol oxidase; Srebf2, sterol-regulatory element binding factor 2; Tm7sf2, D14-sterol reductase; Tmem97, transmembrane protein 97; Vkorc1, vitamin K epoxide reductase complex (subunit 1); VLDL, very low density lipoprotein; Vrk3, vaccini...

The Lys198Asn polymorphism does not directly contribute to the incidence of pre-eclampsia. However, the association of the T-allele with raised blood pressure and the T/T genotype with increased plasma ET-1 levels suggest that this polymorphism may interact with other genes or environmental factors to sensitize pregnant women to develop pre-eclampsia.