Maternal Dietary Fatty Acid Composition and Newborn Epigenetic Aging—A Geometric Framework Approach

Background Maternal nutrition is associated with epigenetic and cardiometabolic risk factors in offspring. Research in humans has primarily focused on assessing the impact of individual nutrients. Objective We sought to assess the collective impact of maternal dietary monounsaturated (MUFA), polyunsaturated (PUFA), and saturated fat (SFA) on epigenetic aging and cardiometabolic risk markers in healthy newborn infants using a geometric framework approach. Design Body fatness (n = 162), aortic intima-media thickness (n = 131), heart rate variability (n = 118), and epigenetic age acceleration (n = 124) were assessed in newborn infants. Maternal dietary intake was cross-sectionally assessed in the immediate postpartum period via a validated 80-item self-administered food-frequency questionnaire. Generalized additive models were used to explore interactive associations of nutrient intake, with results visualized as response surfaces. Results After adjustment for total energy intake, maternal age, gestational age, and sex there was a 3-way interactive association of MUFA, PUFA, and SFA (P = 0.001) with newborn epigenetic aging. This suggests that the nature of each fat class association depends upon one another. Response surfaces revealed MUFA was positively associated with newborn epigenetic age acceleration only at proportionately lower intakes of SFA or PUFA. We also demonstrate a potential beneficial association of omega-3 PUFA with newborn epigenetic age acceleration (P = 0.008). There was no significant association of fat class with newborn aortic intima-media thickness, heart rate variability, or body fatness. Conclusions In this study, we demonstrate an association between maternal dietary fat class composition and epigenetic aging in newborns. Future research should consider other characteristics such as the source of maternal dietary fatty acids.

Influence of intrauterine growth status on aortic intima-media thickness and aortic diameter in near-term fetuses: a comparative cross-sectional study

Intrauterine undernutrition may lead to fetal vascular programming. We compared abdominal aortic intima-media thickness (aIMT) and aortic diameter (aD) between appropriate for gestational age (AGA) and growth-restricted fetuses (GRF). We recruited 136 singleton fetuses at 34–37 weeks of gestation from Fetal Medicine Unit of Aga Khan University Hospital, Karachi (January–November 2017). Subjects were classified as AGA (n = 102) and GRF (n = 34) using INTER-GROWTH 21st growth reference and standard ultrasound protocol. Their far- and near-wall aIMT and aD were compared after adjustment of maternal age, first-trimester body mass index, fetal gender, hypertension and hyperglycemia in pregnancy. As the severity of growth restriction increased in GRF, aIMT and aD showed an increasing and a decreasing trend, respectively. Both far- and near-wall aIMT in GRF [(adj. β = 0.082, 95% confidence interval [CI] 0.042–0.123) and (adj. β = 0.049, 95% CI 0.010–0.089)] were significantly greater with reference to AGA fetuses. GRF subgroup analysis into small for gestational age (SGA) fetuses and intrauterine growth restricted (IUGR) revealed highly significant difference between AGA and IUGR for far (0.142 mm, P-value < 0.001) and near-wall aIMT (0.115 mm, P-value < 0.001) and marginally significant aD difference (0.51 mm, P-value 0.05). These findings suggest that the extent of fetal aortic remodelling is influenced by the severity of growth restriction. Hence, the targeted interventions for the cardiovascular health promotion of IUGR and SGA born neonates are desirable during early childhood, particularly in set ups with high prevalence of low birth weight babies.

Hydroxytyrosol Acetate Inhibits Vascular Endothelial Cell Pyroptosis via the HDAC11 Signaling Pathway in Atherosclerosis

Hydroxytyrosol acetate (HT-AC), a natural polyphenolic compound in olive oil, exerts an anti-inflammatory effect in cardiovascular diseases (CVDs). Pyroptosis is a newly discovered form of programmed inflammatory cell death and is suggested to be involved in the atherosclerosis (AS) process. However, the effect of HT-AC on vascular endothelial cell pyroptosis remains unknown. Thus, we aimed to investigate the effect of HT-AC on vascular endothelial cell pyroptosis in AS and related signaling pathways. In vivo studies showed that HT-AC alleviated the formation of atherosclerotic lesions and inhibited pyroptosis in the aortic intima of ApoE−/− mice fed a high-fat diet (HFD) for 12 weeks. In vitro, we found that HT-AC treatment of human umbilical vein endothelial cells (HUVECs) alleviated tumor necrosis factor-alpha (TNF-α)-induced pyroptosis by decreasing the number of PI positive cells, decreasing the enhanced protein expressions of activated caspase-1 and gasdermin D (GSDMD), as well as by decreasing the release of pro-inflammatory interleukin (IL)-1β and IL-6. Besides, HT-AC down-regulated HDAC11 expression in the aortic intima of HFD-fed ApoE−/− mice and TNF-α-stimulated HUVECs. To determine the underlying mechanism of action, molecular docking and drug affinity responsive target stability (DARTS) were utilized to identify whether HDAC11 protein is a target of HT-AC. The molecular docking result showed good compatibility between HT-AC and HDAC11. DARTS study's result showed that HDAC11 protein may be a target of HT-AC. Further study demonstrated that knockdown of HDAC11 augmented the inhibition of HT-AC on pyroptosis in TNF-α-stimulated HUVECs. These findings indicate that HT-AC might prevent vascular endothelial pyroptosis through down-regulation of HDAC11 related signaling pathway in AS.

Maternal Dietary Carbohydrate Intake and Newborn Aortic Wall Thickness

Evidence from animal models indicates that maternal diet during pregnancy affects offspring cardiometabolic health. Improving carbohydrate quality during high-risk pregnancies reduces aortic intima-medial thickness; a marker for early atherosclerosis; in the infant offspring. We sought to determine whether maternal carbohydrate quantity and quality are associated with newborn aortic intima-medial thickness in healthy pregnancies. Maternal diet throughout pregnancy was evaluated in 139 mother–child dyads using a validated food frequency questionnaire. Carbohydrate intake was expressed as quantity (% total energy), quality (fibre, glycaemic index), and glycaemic burden (glycaemic load). Aortic intima-medial thickness was measured by high-frequency ultrasound of the neonatal abdominal aorta. Neither quantity nor quality of maternal carbohydrate intake during pregnancy was associated with meaningful differences in offspring maximum aortic intima-medial thickness with the exception of fibre intake in women with overweight or obesity which was inversely associated (−8 μm [95% CI −14, −1] per g fibre, p = 0.04). In healthy pregnancy, the quantity and quality of maternal carbohydrate intake is likely not a meaningful modifiable lifestyle factor for influencing offspring vascular health. The effect of carbohydrate quality may only be evident in high-risk pregnancies, consistent with previous findings. These findings may be confirmed in prospective dietary trials in pregnancy.

Abdominal Aortic Intima-Media Thickness Predicts Coronary Artery Disease Severity in Patients With Stable Angina Pectoris: A Prospective Study

Accurately identifying coronary artery disease (CAD) is the key element in guiding the work-up of patients with suspected angina. Thickening of the arterial wall is a hallmark of atherosclerosis. Therefore, the main purpose of this study was to determine whether abdominal aortic intima-media thickness (AAIMT), which is the earliest zone of atherosclerotic manifestations, has a predictive value in CAD severity. A total of 255 consecutive patients who were referred for invasive coronary angiography due to suspected stable angina pectoris were prospectively included in the study. B-mode ultrasonography was used to determine AAIMT before coronary angiography. Coronary artery disease severity was assessed with the SYNTAX score (SS). A history of hypertension, age, dyslipidemia, and higher AAIMT (odds ratio: 2.570; 95%CI 1.831-3.608; P < .001) were independent predictors of intermediate or high SS. An AAIMT <1.3 mm had a negative predictive value of 98% for the presence of intermediate or high SS and 83% for obstructive CAD. In conclusion, AAIMT showed a significant and independent predictive value for intermediate or high SS. Therefore, AAIMT may be a noninvasive and useful tool for decision-making by cardiologists (eg, to use a more invasive approach).

Radiation Impacts Early Atherosclerosis by Suppressing Intimal LDL Accumulation

Rationale: Bone marrow transplantation (BMT) is used frequently to study the role of hematopoietic cells in atherosclerosis, but aortic arch lesions are smaller in mice after BMT. Objective: To identify the earliest stage of atherosclerosis inhibited by BMT and elucidate potential mechanisms. Methods and Results: Ldlr -/- mice underwent total body γ-irradiation, bone marrow reconstitution and 6-week recovery. Atherosclerosis was studied in the ascending aortic arch and compared to mice without BMT. In BMT mice neutral lipid and myeloid cell topography were lower in lesions after feeding a cholesterol-rich diet (CRD) for 3, 6 and 12 weeks. Lesion coalescence and height were suppressed dramatically in mice post-BMT, whereas lateral growth was inhibited minimally. Targeted radiation to the upper thorax alone reproduced the BMT phenotype. Classical monocyte recruitment, intimal myeloid cell proliferation and apoptosis did not account for the post-BMT phenotype. Neutral lipid accumulation was reduced in 5-day lesions, thus we developed quantitative assays for LDL accumulation and paracellular leakage using DiI-labeled human LDL and rhodamine B-labeled 70kD dextran. LDL accumulation was dramatically higher in the intima of Ldlr -/- relative to Ldlr +/+ mice, and was inhibited by injection of HDL mimics, suggesting a regulated process. LDL, but not dextran, accumulation was lower in mice post-BMT both at baseline and in 5-day lesions. Since the transcript abundance of molecules implicated in LDL transcytosis was not significantly different in the post-BMT intima, transcriptomics from whole aortic arch intima, and at single cell resolution, was performed to give insights into pathways modulated by BMT. Conclusions: Radiation exposure inhibits LDL entry into the aortic intima at baseline and the earliest stages of atherosclerosis. Single cell transcriptomic analysis suggests that LDL uptake by endothelial cells is diverted to lysosomal degradation and reverse cholesterol transport pathways. This reduces intimal accumulation of lipid and impacts lesion initiation and growth.

A macrophage-specific lncRNA regulates apoptosis and atherosclerosis by tethering HuR in the nucleus

Long non-coding RNAs (lncRNAs) are emerging regulators of pathophysiological processes including atherosclerosis. Using RNA-seq profiling of the intima of lesions, here we identify a macrophage-specific lncRNA MAARS (Macrophage-Associated Atherosclerosis lncRNA Sequence). Aortic intima expression of MAARS increases by 270-fold with atherosclerotic progression and decreases with regression by 60%. MAARS knockdown reduces atherosclerotic lesion formation by 52% in LDLR−/− mice, largely independent of effects on lipid profile and inflammation, but rather by decreasing macrophage apoptosis and increasing efferocytosis in the vessel wall. MAARS interacts with HuR/ELAVL1, an RNA-binding protein and important regulator of apoptosis. Overexpression and knockdown studies verified MAARS as a critical regulator of macrophage apoptosis and efferocytosis in vitro, in an HuR-dependent manner. Mechanistically, MAARS knockdown alters HuR cytosolic shuttling, regulating HuR targets such as p53, p27, Caspase-9, and BCL2. These findings establish a mechanism by which a macrophage-specific lncRNA interacting with HuR regulates apoptosis, with implications for a broad range of vascular disease states.