Does VLDL-LDL-cholesterol in cord serum predict future level of lipoproteins?

Sex differences in lipids: A life course approach

Differences between men and women in lipids and lipoproteins are observed in distribution and trajectory from infancy to adulthood in the general population. However, these differences are more pronounced in hereditary lipid disorders such as familial hypercholesterolemia (FH) when absolute cholesterol levels are higher from birth onwards. In the early life course, girls compared to boys have higher low-density lipoprotein cholesterol (LDL-C) levels and total cholesterol, while high-density lipoprotein cholesterol (HDL-C) levels are similar. In early adulthood to middle-age, women have lower LDL-C and higher HDL-C levels, as LDL-C levels increase and HDLC levels decrease in men. In the elderly, all lipids - total cholesterol, LDL-C, HDL-C and triglyceride levels decrease but are more pronounced in men. Lipid levels are also affected by specific transitions in girls/women such as the menstrual cycle, pregnancy, breastfeeding and menopause. Lipid levels fluctuate during the menstrual cycle. During pregnancy a physiological increase of LDL-C and even a larger increase in triglyceride levels are observed. Pregnancy has a double impact on LDL-C accumulation in women with FH as they have to stop statins, and the absolute increase in LDL-C is higher than in women without FH. In the menopausal transition, women develop a more adverse lipid profile. Therefore, it is important to take into account both sex and the life course when assessing a lipid profile.

The Association Between Perfluoroalkyl Substances and Lipids in Cord Blood

INTRODUCTION

Perfluoroalkyl substances (PFAS) were among various persistent organic pollutants suspected to have been released during the collapse of the World Trade Center (WTC) on 9/11/2001. Evidence suggests that PFAS may have cardiometabolic effects, including alterations in lipid profiles. This study evaluated the association between cord blood PFAS and lipids in a population prenatally exposed to the WTC disaster.

STUDY POPULATION

222 pregnant women in the Columbia University WTC birth cohort enrolled between December 13, 2001 and June 26, 2002 at hospitals located near the WTC site: Beth Israel, St. Vincent's, and New York University Downtown.

METHODS

We evaluated the association between 5 cord blood PFAS-perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorohexanesulfonic acid (PFHxS), perfluorononanoic acid (PFNA), perfluorodecane sulfonate (PFDS)-and cord blood lipids (total lipids, total cholesterol, triglycerides).

RESULTS

Median (interquartile range [IQR]) concentrations of PFAS were 6.32 (4.58-8.57), 2.46 (1.77-3.24), 0.38 (0.25-0.74), 0.66 (0.48-0.95) and 0.11 (0.09-0.16) ng/mL for PFOS, PFOA, PFNA, PFHxS, and PFDS, respectively. Median (IQR) for lipids were 59.0 (51.5-68.5) mg/dL for total cholesterol, 196.5 (170.5-221.2) mg/dL for total lipids and 33.1 (24.2-43.9) mg/dL for triglycerides. In fully adjusted models, several PFAS were associated with higher lipid levels, including evidence of a strong linear trend between triglycerides and both PFOA and PFHxS.

CONCLUSIONS

Findings support previous evidence of an association between PFAS exposure and altered lipid profiles and add novel information on this relationship in cord blood, as well as for an understudied PFAS, PFDS (J Clin Endocrinol Metab XX: 0-0, 2019).

Dietary supplementation with L-lysine affects body weight and blood hematological and biochemical parameters in rats

L-Lysine (Lys) is a popular additive in foods, but the physiological effects of excess Lys supplementation are poorly understood and upper limits of safe intake have not been established. The objectives of this study were to examine the effects of dietary supplementation with increasing amounts of Lys on body weight (BW), food intake, and various blood hematological and biochemical parameters in rats. Male Sprague-Dawley rats at 10 weeks of age were assigned to ten diet groups (eight rats/group) and fed diets containing either 7% or 20% casein and supplemented with either 0% (Control), 1.5%, 3%, 6% Lys, or 6% Lys + 3% arginine for 1 week. Rats fed 7% casein with ≥ 1.5% Lys supplementation had lower serum albumin and leptin and higher LDL cholesterol (LDLC), ratios of total cholesterol (TC):HDL cholesterol (HDLC) and LDLC:HDLC than those fed 7% casein Control diet (P < 0.05). Rats fed 7% casein diet supplemented with 3% Lys diet had lower BW gain, food intake, serum alkaline phosphatase activity, and increased mean corpuscular hemoglobin concentration, blood urea nitrogen and serum pancreatic polypeptide compared to rats fed the Control diet (P < 0.05). Addition of 6% Lys in 7% casein caused significant BW loss (P < 0.001) and altered additional parameters. Addition of 6% Lys in a 20% casein diet reduced BW gain and food intake and altered numerous parameters. Arg supplementation normalized many of the endpoints changed by Lys. Collectively, these results show that Lys supplementation affects BW, food intake and a number of hematological and biochemical parameters. These effects of Lys supplementation were confined primarily in diets with lower levels of dietary protein. In the context of a low protein diet (7% casein), levels of Lys supplementation ≥ 1.5% may exert adverse health effects in rats.

Relationship between copper and lipids and atherogenic indices soon after birth in Japanese preterm infants of 32–35 weeks

Several studies have reported association of altered levels of lipids and some trace elements with risk factors for cardiovascular disease development in adulthood. Accordingly, the present study aimed to determine the relationship among the serum levels of copper (Cu), zinc (Zn), lipids, lipoproteins and apolipoproteins in preterm infants through an assessment of atherogenic indices shortly after birth. Blood samples were collected within 20 min of birth from 45 preterm infants with gestational ages ranging from 32 to 35 weeks. Serum Cu, Zn, total cholesterol (TC), low-density lipoprotein cholesterol (LDLc), high-density lipoprotein cholesterol (HDLc), apolipoprotein-A1 (apoA1) and apolipoprotein-B (apoB) levels were measured, and the TC/HDLc, LDLc/HDLc and apoB/apoA1 ratios were calculated. Upon determining the correlation between the levels of Cu, Zn and these indices of lipid metabolism, triglyceride (TG) and Cu were found to correlate negatively with birth weight (BW) and the standard deviation (s.d.) score for body weight. Furthermore, Cu levels correlated positively with the TG level and TC/HDLc, LDLc/HDLc and apoB/apoA1 ratios and negatively with the HDLc level and HDLc/apoA1 ratios. However, a stepwise multiple regression analysis indicated that the s.d. score for BW and TG level were significant independent determinants of the Cu level. In contrast, Zn did not correlate with any of these indices. In conclusion, intrauterine growth restriction and the TG level at birth influence Cu levels in preterm infants, whereas atherogenic indices do not affect this parameter.

Lipid profile and atherogenic indices soon after birth in Japanese preterm infants

AIM

The intra-uterine environment affects the risk of development of cardiovascular disease in adulthood. The aim of this study was to determine the influence of prematurity and foetal growth restriction on lipid metabolism, by assessing atherogenic indices soon after birth in preterm infants.

METHODS

Blood samples were collected within 20 min of birth from 80 preterm infants with a gestational age of ≤35 weeks. Serum total cholesterol (TC), low-density lipoprotein cholesterol (LDLc), high-density lipoprotein cholesterol (HDLc), apolipoprotein-A1 (apoA1) and apolipoprotein-B (apoB) levels were measured. The ratio of TC/HDLc, LDLc/HDLc and apoB/apoA1 were also calculated. Correlations between these indices and gestational age, birth weight and the standard deviation (SD) score for birth weight were also determined.

RESULTS

Gestational age, birth weight and SD score for birth weight were negatively correlated with the TC/HDLc, LDLc/HDLc and apoB/apoA1 ratios.

CONCLUSION

In preterm infants, prematurity and poor foetal growth may influence lipid and apolipoprotein metabolism and affect atherogenic indices at birth.

Low-density lipoprotein profile changes during the neonatal period

OBJECTIVE

To investigate natural change of low-density lipoprotein (LDL) profile during the neonatal period and the impact of gestational age and birth weight on those changes.

STUDY DESIGN

We measured lipid composition in LDL fraction, LDL particle size and apolipoprotein B (apoB) concentration at birth, 5 days of age and 1 month of age in 63 healthy neonates that had 37 to 41-week gestational age.

RESULT

Low-density lipoprotein cholesterol and apoB concentrations increased from birth to 5 days of age, and the concentration persisted at 1 month in breast-fed and mixed-fed infants. However, in formula-fed infants, the concentration decreased at 1 month. At 5 days of age, neonates had larger and more triglyceride (TG)-rich LDL particles than at birth. At 1 month of age, LDL particles were smaller and more cholesterol rich than at 5 days of age. Single regression analyses showed that gestational age had influenced the LDL profile at birth and 5 days of age, while at 1 month milk determined the profile.

CONCLUSION

The number of LDL particles increased rapidly during the first 5 days of life, and the composition of LDL particles is modulated by TG content throughout the neonatal period. Gestational age and milk, rather than birth weight, determine postnatal changes in LDL profile.

Cord Blood Lipids in Infants Born to HIV-1-Infected Women Treated with Combination Antiretroviral Therapy

Background

To investigate the effect of exposure to protease inhibitor (PI) therapy in utero on cord blood lipids in infants born to mothers enrolled in AIDS Clinical Trials Group protocol 5084, a prospective, multi-centre, observational study of antiretroviral therapy (ART) during pregnancy.

Methods

Clinical outcome was determined in 80 infants born to women treated with PIs and 73 infants born to women treated with other antiretrovirals during pregnancy. Cord blood serum from 117 of these infants was assayed for total, low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol, triglyceride, apolipoprotein A1 (apoA1), apolipoprotein B100 (apoB) and lipoprotein (a). Covariates considered in the analysis included race/ethnicity, gestational age, infant gender, infant birth weight, mode of delivery, maternal tobacco and alcohol use, post-partum body mass index, and ART duration.

Results

Cord blood total and HDL cholesterol, triglyceride, apoA1, apoB, lipoprotein (a) and apoB/apoA1 ratio were not different between the two groups. Cord blood lipid levels in these HIV-exposed infants were similar to those reported in other neonatal cohorts. Controlling for race/ethnicity, infants born to women treated with PIs had higher LDL cholesterol than those born to women not treated with PIs (29 mg/dl versus 27 mg/dl, P=0.006).

Conclusion

Only LDL cholesterol was significantly higher in the cord blood of PI-exposed infants versus those not exposed to PIs in utero. As the difference between the two groups was small, the clinical relevance of the effect of maternal PI treatment on infant LDL cholesterol levels at birth is not clear.

Lipid and lipoprotein concentrations at age 4. Association with neonatal and parental levels

BACKGROUND AND OBJECTIVE

To study the influence of diet, anthropometrical measurements and neonatal and parental lipoprotein variables on lipoprotein concentrations at age 4.

SUBJECTS AND METHOD

18 neonates with normal serum lipoprotein values (group 1), 19 neonates with high total cholesterol (TC) levels (group 2) and 21 neonates with normal TC but altered levels in other lipids, apolipoproteins, lipoproteins or ratios (group 3) were selected for a follow-up study. Body weight, body mass index (BMI) and the suitability of diet at age 4 for coronary heart disease prevention were evaluated. Multivariable stepwise linear regression analyses were performed for each lipid or lipoprotein parameter at age 4 considering group at birth, diet, neonatal and parental BMI, lipid or lipoprotein parameters.

RESULTS

A large percentage of 4 year-olds had high low density lipoproteins-cholesterol (LDLc) and low high density lipoproteins-cholesterol (HDLc) and followed an unsuitable diet. Prevalence of altered lipoprotein variables, except for TC/HDLc, was similar in the 3 groups. Correlations of birth versus 4 year levels were significant (p = 0.021-0.0001) for all parameters except triglycerides, TC and LDLc. However, all tracking correlations were not significant in group 3. In the multiple regression study, parental and neonatal parameters were retained as explicative variables in many of the models but diet was not retained in any of them. Maternal concentrations were always more explicative than paternal or neonatal ones. Models for TC/HDLc and LDLc/HDLc were the most explicative (both, R2 > 0.578; p < 0.0001).

CONCLUSIONS

Lipoprotein variables at age 4 were more closely associated with progenitors' and neonatal lipoprotein values than BMI or diet.

n − 3 Fatty acid supplementation during pregnancy in women with allergic disease: effects on blood pressure, and maternal and fetal lipids

n−3 Fatty acids derived from fish oil reduce plasma triacylglycerols (triglycerides) and increase HDL-C (high-density lipoprotein cholesterol); however, the effect of n−3 fatty acid supplementation during pregnancy, a hyperlipidaemic state, remains unknown. We took the opportunity to investigate maternal lipid levels and blood pressure during and after pregnancy, and fetal lipid levels at birth, in a study that aimed primarily to examine the effect of fish oil supplementation during pregnancy on immune function in infants born to women with allergic disease. Eighty-three pregnant women who had allergic disease, but were otherwise healthy, completed the study. They were randomly allocated to receive fish oil or olive oil capsules, taken as 4 g/day, from 20 weeks of pregnancy until delivery. Compared with olive oil, fish oil supplementation did not alter triacylglycerols, total cholesterol, LDL-C (low-density lipoprotein cholesterol) or HDL-C during or after pregnancy. There was also no effect of fish oil on cord blood triacylglycerols, total cholesterol, LDL-C or HDL-C. Fish oil supplementation during pregnancy did not alter maternal blood pressure during or after pregnancy. The effects of fish oil on lipids and blood pressure in non-pregnant individuals appear to be lost when it is administered during pregnancy.

Cord blood lipoproteins and prenatal influences

PURPOSE OF REVIEW

Blood lipoprotein profiles in early life are known to be related to and predictive of those in adulthood, but little is known about their determinants. Genetic and environmental influences affect cord blood lipoproteins, but how this occurs and the relative contribution of these influences to the overall profile in healthy newborns remains uncertain.

RECENT FINDINGS

This review discusses findings from a range of earlier and more recent studies, and summarizes the key influences on cord blood lipoproteins. In particular, we review the potential contribution of maternal blood total cholesterol levels during pregnancy and the increased maternal transmission in newborns of mothers with diabetes.

SUMMARY

In cord blood, cholesterol levels are lower than in adults and the relative proportion present in HDL as opposed to LDL is much higher. The currently available evidence suggests that several factors influence the composition of cord blood lipoproteins. Although inheritance of major monogenic disorders can affect cord lipids in general, the genetic contribution appears to be minimal, although effects of the proprotein convertase subtilisin/kexine type 9 gene (PCSK9) need fuller exploration in this regard in certain ethnic groups. Evidence is summarized that maternal lipoprotein levels, particularly those due to diet or induced by pregnancy, influence cord lipid levels. Placental insufficiency and other conditions affecting fetal growth and the mode of delivery may also influence cord lipoprotein concentrations. How maternal glucose tolerance during pregnancy affects cord blood lipoproteins remains unclear. In view of increasing evidence that cardiovascular risk may have prenatal antecedents, this would seem to be an important area for further investigation.

Fetal cord plasma lipoprotein status in uncomplicated human pregnancies and in pregnancies complicated by pre-eclampsia and intrauterine growth restriction

Maternal lipids have been studied extensively in pre-eclampsia (PE) and intrauterine growth restriction (IUGR) but little is known about fetal lipids. We hypothesised that the maternal lipid perturbations in PE and IUGR pregnancies would result in similar alterations in the fetal lipid profile. We performed a cross-sectional case control study of maternal and fetal (delivery venous cord blood) lipid and lipoprotein concentrations in third trimester uncomplicated pregnancies (n = 81) and in pregnancies complicated by PE (n = 23) or IUGR (n = 17). In uncomplicated pregnancies, fetal log total cholesterol (TC), log triglyceride (TG) and high-density lipoprotein cholesterol (HDL-C) levels were significantly affected by mode of delivery. Fetal log TC (r = 0.37, P = 0.02), log TG (r = 0.34, P = 0.04) and TC/HDL-C ratio (r = 0.31, P = 0.05) were positively correlated with placental weight. Maternal TC (r = 0.35, P = 0.03) and LDL levels (r = 0.36, P = 0.02) were associated with fetal HDL-C levels. Maternal TC was significantly elevated in PE [mean 6.75 (standard deviation 1.14) mmol/L] compared to BMI-matched controls [5.94 (0.89) mmol/L P = 0.04]. In PE, fetal log TC [mean 0.36 (0.23) versus 0.11 (0.15) log mmol/L, P = 0.03], fetal log TG [-0.21 (0.32) versus -0.49 (0.26) log mmol/L, P = 0.02] and fetal TC/HDL-C ratio [3.64 (1.62) versus 1.80 (0.86), P = 0.001] were higher than in controls, after adjustment for mode of delivery. In IUGR, fetal log TG [-0.17 (0.35) versus -0.57 (0.10) log mmol/L, P = 0.01] was higher than controls, after adjustment for mode of delivery. There were no correlations between maternal and fetal lipid levels, or between fetal birth weight and either maternal or fetal lipids in the PE or IUGR groups. We conclude that although fetal lipids do not show a direct correlation with maternal lipids in PE or IUGR, these complications of pregnancy significantly impact upon fetal lipid levels possibly due to increased fetal stress or compromised placental lipid transport. Our findings are potentially pertinent to understanding the future cardiovascular health of the offspring.