The role of retinol-binding protein 4 and its relationship with sex hormones in coronary artery disease
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
Authors: Wang, Hongxia; Zhou, Ping; Zou, Dan; Liu, Ying; Lu, Xiang; Liu, Zhengxia
Abstract
The role of retinol-binding protein 4 (RBP4) in patients with coronary artery disease (CAD) with different sexes has not been clearly established. Sex hormones, especially testosterone (T) and estradiol (E2), have been considered to play an important role in CAD. This study aimed to investigate the role of RBP4 and the possible association between RBP4 and T and E2 in CAD. The study included 658 individuals who underwent coronary angiography (CAG); they were assigned to CAD group (n = 440) and controls (n = 218). CAD group was subdivided into three subgroups. Serum RBP4 and T were assayed by enzyme linked immunosorbent assay. Serum E2 was measured using electrochemiluminescence immunoassay. For men, RBP4 levels were lower in CAD group, especially those with acute myocardial infarction, than in controls (P < 0.05, P < 0.01, respectively). For women, no significant difference was found in RBP4 levels between both groups. RBP4 was positively correlated with T in male patients with CAD (r = 0.124, P < 0.05). Logistic regression analysis showed that RBP4 was a protective factor for CAD (odds ratio 0.975, 95% confidence interval 0.958-0.993; P = 0.007). In conclusion, RBP4 levels were significantly decreased and positively related with T in men with CAD. Higher RBP4 levels were associated with lower risk of CAD. RBP4 may play a potential protective role for CAD among men. (C) 2018 Elsevier Inc. All rights reserved.
Cyp1b1 directs Srebp-mediated cholesterol and retinoid synthesis in perinatal liver; Association with retinoic acid activity during fetal development
PLOS ONE
Authors: Maguire, Meghan; Larsen, Michele Campaigne; Vezina, Chad M.; Quadro, Loredana; Kim, Youn-Kyung; Tanumihardjo, Sherry A.; Jefcoate, Colin R.
Abstract
Background Cytochrome P450 1b1 (Cyp1b1) deletion and dietary retinol deficiency during pregnancy (GVAD) affect perinatal liver functions regulated by Srebp. Cyp1b1 is not expressed in perinatal liver but appears in the E9.5 embryo, close to sites of retinoic acid (RA) signaling. Hypothesis Parallel effects of Cyp1b1 and retinol on postnatal Srebp derive from effects in the developing liver or systemic signaling. Approach Cluster postnatal increases in hepatic genes in relation to effects of GVAD or Cyp1b1 deletion. Sort expression changes in relation to genes regulated by Srebp1 and Srebp2.Test these treatments on embryos at E9.5, examining changes at the site of liver initiation. Use in situ hybridization to resolve effects on mRNA distributions of Aldh1a2 and Cyp26a1 (RA homeostasis); Hoxb1 and Pax6 (RA targets). Assess mice lacking Lrat and Rbp4 (DKO mice) that severely limits retinol supply to embryos. Results At birth, GVAD and Cyp1b1 deletion stimulate gene markers of hepatic stellate cell (HSC) activation but also suppress Hamp. These treatments then selectively prevent the postnatal onset of genes that synthesize cholesterol (Hmgcr, Sqle) and fatty acids (Fasn, Scd1), but also direct cholesterol transport (Ldlr, Pcsk9, Stard4) and retinoid synthesis (Aldh1a1, Rdh11). Extensive support by Cyp1b1 is implicated, but with distinct GVAD interventions for Srebp1 and Srebp2. At E9.5, Cyp1b1 is expressed in the septum transversum mesenchyme (STM) with beta-carotene oxygenase (Bco1) that generates retinaldehyde. STM provides progenitors for the HSC and supports liver expansion. GVAD and Cyp1b1-/- do not affect RA-dependent Hoxb1 and Pax6. In DKO embryos, RA-dependent Cyp26a1 is lost but Hoxb1 is sustained with Cyp1b1 at multiple sites. Conclusion Cyp1b1-/- suppresses genes supported by Srebp. GVAD effects distinguish Srebp1 and Srebp2 mediation. Srebp regulation overlaps appreciably in cholesterol and retinoid homeostasis. Bco1/Cyp1b1 partnership in the STM may contribute to this later liver regulation.