In the current study, we employed a model of human apoE targeted replacement mice and HFD-induced obesity to study the potential link between E4 and IR, at rest and following a postprandial challenge.
Herein, we compare the m- and h-APOE multi-gene clusters, and then critically review the relevant history and approaches to developing a Tg mouse model to characterize APOE-dependent AD pathology, in combination with genetic (sex, age) and modifiable (e.g., inflammation, obesity) risk factors.
Besides its well-established role in pathology of CVD, it is also implicated in neurodegenerative diseases and recent new data on adipose-produced apoE point to a novel metabolic role for apoE in obesity.
In contrast, peripherally expressed APOE3 is associated with a notable shift of substrate oxidation towards non-shivering thermogenesis in visceral WAT mitochondria, leading to resistance to obesity.
We used cardiac biopsies from human diabetic (n=23) and nondiabetic patients (n=19), cultured rat cardiomyocytes, left ventricular tissue from apolipoprotein E-deficient mice with streptozotocin-induced diabetes mellitus (n=12-22), and ZSF1 (obese diabetic Zucker fatty/spontaneously hypertensive heart failure F1 hybrid) rats (n=5-6) and analyzed insulin-dependent signaling pathways that modulate titin phosphorylation.
Using apolipoprotein E knock-out (apoE<sup>-/-</sup>) mice on a high fat (HF) diet as an atherosclerotic obesity model, we demonstrated 1) microRNA-155 (miRNA-155, miR-155) is significantly up-regulated in the aortas of apoE<sup>-/-</sup> mice, and miR-155 deficiency in apoE<sup>-/-</sup> mice inhibits atherosclerosis; 2) apoE<sup>-/-</sup>/miR-155<sup>-/-</sup> (double knock-out (DKO)) mice show HF diet-induced obesity, adipocyte hypertrophy, and present with non-alcoholic fatty liver disease; 3) DKO mice demonstrate HF diet-induced elevations of plasma leptin, resistin, fed-state and fasting insulin and increased expression of adipogenic transcription factors but lack glucose intolerance and insulin resistance.
We evaluated predictors including demographics, APOE, intellectual enrichment, midlife risk factors (physical inactivity, obesity, smoking, diabetes, hypertension, and dyslipidemia), and the total number of late-life cardiac and metabolic conditions.
The best interaction model for predicting obesity risk by MDR analysis was the three factor model including POMC (C > T), MC4R (T > C) and APOE (Hha1) polymorphisms.
In genetic association studies adjusted for age, BMI SDS and sex, we identified significant associations for rs599839 near SORT1 with TC and LDL-C and for rs4420638 near APOE with TC and LDL-C. We performed Bayesian modelling of the combined lipid phenotype of HDL-C, LDL-C and TG to identify potentially causal polygenic effects on this multi-dimensional phenotype and considering obesity, age and sex as a-priori modulating factors.
This study aimed to determine whether relationships between obesity, as measured by waist-to-hip ratio (WHR), and cognition and brain structure were modified by the apolipoprotein epsilon 4 allele (apoE4).
We use our algorithm to characterize the effect of genetic markers and liver gene expression traits on mouse obesity related phenotypes, including weight, cholesterol, glucose, and free fatty acid levels, in an experiment previously used for discovery and validation of network connections: an F2 intercross between the C57BL/6 J and C3H/HeJ mouse strains, where apolipoprotein E is null on the background.
Two SNPs, CETP Ile405Val and APOECys112Arg, were associated with both the prevalence of low HDL-cholesterol level (Ile405Val P = < .0001; Cys112Arg P = 0.001) and with the prevalence of abdominal obesity (Ile405Val P = 0.007; Cys112Arg P = 0.007).
The strength of the relation and the similarity of the results obtained for both tested indicators of obesity provide firm evidence that APOE plays an important role in obesity development in the Roma population.