The effects of intrauterine malnutrition on maternal-fetal cholesterol transport and fetal lipid synthesis in mice

Comparison of lncRNA Expression in the Uterus between Periods of Embryo Implantation and Labor in Mice

Simple Summary

Progesterone has been proven to play an important role in female mammals during pregnancy. In this study, the uteri of pregnant mice were collected to compare mRNA and lncRNA expression between periods of embryo implantation and labor. The results show that 19 known differentially expressed lncRNAs and 31 novel differentially lncRNAs were commonly expressed between the two stages, indicating that these lncRNAs’ function is related to progesterone.

Abstract

Uterine function during pregnancy is regulated mainly by progesterone (P4) and estrogen (E2). Serum P4 levels are known to fluctuate significantly over the course of pregnancy, especially during embryo implantation and labor. In this study, pregnant mice at E0.5, E4.5, E15.5, and E18.5 (n = 3/E) were used for an RNA-Seq-based analysis of mRNA and lncRNA expression. In this analysis, 1971 differentially expressed (DE) mRNAs, 493 known DE lncRNAs, and 1041 novel DE lncRNAs were found between E0.5 and E4.5 at the embryo implantation stage, while 1149 DE mRNAs, 192 known DE lncRNAs, and 218 novel DE lncRNAs were found between E15.5 and E18.5 at the labor stage. The expression level of lncRNA-MMP11 was significantly downregulated by P4 treatment on MSM cells, while lncRNA-ANKRD37 was significantly upregulated. Notably, 117 DE mRNAs, 19 known DE lncRNAs, and 31 novel DE lncRNAs were commonly expressed between the two stages, indicating that these mRNAs and lncRNAs may be directly or indirectly regulated by P4.

Early-life exposure to the Chinese famine and risk of carotid intima-media thickness increased in adulthood

BACKGROUND AND AIMS

Little was known about the effect of famine exposure on carotid intima-media thickness (cIMT). The present study aimed to explore the relationship in a Chinese population.

METHODS AND RESULTS

Participants were divided into five groups: not exposed to famine, exposed to famine in fetal, early, mid or late childhood. Elevated cIMT was defined as a thickness of >0.9 mm measured by carotid ultrasound. Multivariate logistic regression was performed to calculate odds ratio (OR) and confidence interval (CI) between famine exposure and cIMT. A total of 2637 (970 male, mean age 59.1 ± 3.65 years) participants were recruited, and 491 (18.62%) of them had elevated cIMT. When compared with the non-exposure group, the fully adjusted ORs for increased cIMT for exposure in fetal, early, mid to late childhood were 1.321 (95%CI: 0.872, 1.994, P = 0.186), 1.713 (95% CI: 1.188, 2.483, P = 0.004), 2.359 (95% CI: 1.674, 3.357, P < 0.001) and 2.485 (95% CI: 1.773, 3.518, P < 0.001), respectively. Subgroup analyses showed that the exposure to famine did not interact with body mass index, gender, smoking status, hypertension and diabetes history on its effect on cIMT.

CONCLUSION

Our findings indicated that early-life exposure to the Chinese famine might be associated with an increased risk of increased cIMT in adulthood.

Famine Exposure during the Fetal Period Increased the Risk of Dyslipidemia in Female Adults

Chronic diseases are gradually becoming public health challenges around the world. This study was designed to explore the relationship between early life exposure to famine in China and the risk of dyslipidemia during adulthood. A total of 604 subjects born from 1955 to 1965 received a health checkup and completed a questionnaire survey at the health management center of the tertiary hospital in Hefei, China, in 2013. A logistic regression model was used to assess dyslipidemia in famine-exposed and nonexposed individuals. Overall, exposure to famine during the fetal (OR 1.37; 95% CI: 0.90-2.10; and p = 0.14) and childhood (OR 0.97; 95% CI: 0.67-1.41; and p = 0.89) periods did not significantly increase the risk of dyslipidemia in adulthood compared with no exposure group. For females, exposure to famine during the fetal period (OR 2.00; 95% CI: 1.03-3.86; and p = 0.04) significantly increased the risk of dyslipidemia in adulthood compared to no exposure; however, this difference was not found in males. Exposure to famine in early life leads to altered lipid distribution in adulthood, and the risk of dyslipidemia significantly increased in adult women who were exposed to famine during the fetal period. Our study further validated the relationship between famine exposure during pregnancy and increased risk of dyslipidemia in female adult offspring. This study provides a scientific basis for the prevention and control of abnormal blood lipid levels in adults.

Intrauterine growth restriction and genetic determinants - existing findings, problems, and further direction

Fetal growth is determined largely by the nutrient supply, placental transport function, and growth hormones. Recently, gene mutation and expression, especially of those genes associated with the proteins that are related to the fetal growth, have been reported to play an important role in the development of intrauterine growth restriction (IUGR). Fetal growth epigenetics, a new concept in fetal growth, has resulted from studies on fetal programing. This paper outlines the findings of our serial studies on IUGR, and summarizes data on IUGR animal models, placental function in transferring nutrients, cell proliferation dynamics in IUGR, and experimental treatment of IUGR. We review genetic approaches to IUGR, especially those relating to growth factor genes, angiotensinogen genes and other gene mutations. We also discuss the epigenetics of fetal growth and future study directions on fetal growth restriction. These should be valuable in elucidating the mechanisms employed by the fetus and in helping to develop interventional strategies that might prevent the development of IUGR.

High-precision mass spectrometric analysis using stable isotopes in studies of children

The use of stable isotopes combined with mass spectrometry (MS) provides insight into metabolic processes within the body. Herein, an overview on the relevance of stable isotope methodology in pediatric research is presented. Applications for the use of stable isotopes with MS cover carbohydrate, fat, and amino acid metabolism as well as body composition, energy expenditure, and the synthesis of specific peptides and proteins, such as glutathione and albumin. The main focus of these studies is on the interactions between nutrients and the endogenous metabolism within the body and how these factors affect the health of a growing infant. Considering that the early imprinting of metabolic processes hugely impacts metabolism (and thus functional outcome) later in life, research in this area is important and is advancing rapidly. The major fluxes on a metabolic level are the synthesis and breakdown rates. They can be quantified using kinetic tracer analysis and mathematical modeling. Organic MS and isotope ratio mass spectrometry (IRMS) are the two most mature techniques for the isotopic analysis of compounds. Introduction of the samples is usually done by coupling gas chromatography (GC) to either IRMS or MS because it is the most robust technique for specific isotopic analysis of volatile compounds. In addition, liquid chromatography (LC) is now being used more often as a tool for sample introduction of both volatile and non-volatile compounds into IRMS or MS for (13)C isotopic analyses at natural abundances and for (13)C-labeled enriched compounds. The availability of samples is often limited in pediatric patients. Therefore, sample size restriction is important when developing new methods. Also, the availability of stable isotope-labeled substrates is necessary for measurements of the kinetics and concentrations in metabolic studies, which can be a limiting factor. During the last decade, the availability of these substrates has increased. Furthermore, improvements in the accuracy, precision, and sensitivity of existing techniques (such as GC/IRMS) and the development of new techniques (such as LC/IRMS) have opened up new avenues for tackling these limitations.

Sex-dependent programming of glucose and fatty acid metabolism in mouse offspring by maternal protein restriction

BACKGROUND

Nutritional conditions during fetal life influence the risk of the development of metabolic syndrome and cardiovascular diseases in adult life (metabolic programming). Impaired glucose tolerance and dysregulated fatty acid metabolism are hallmarks of metabolic syndrome.

OBJECTIVE

We aimed to establish a mouse model of metabolic programming focusing on the sex-specific effects of a maternal low-protein diet during gestation on glucose and lipid metabolism in the adult offspring.

METHODS

Pregnant C57BL/6 mice received a control or a low-protein diet (18% vs 9% casein) throughout gestation. Male and female offspring received a low-fat or a high-fat diet from 6 to 22 weeks of age.

RESULTS

Maternal low-protein diet during gestation led to deteriorated insulin sensitivity on high-fat feeding in female offspring, as determined by biochemical and microarray analyses. Female offspring of control diet-fed dams were relatively resistant to high-fat diet-induced metabolic dysregulation. In contrast, maternal low-protein diet did not specifically affect the metabolic parameters addressed in male offspring. In males, the high-fat diet led to insulin insensitivity regardless of the diet of the dam.

CONCLUSIONS

Our findings show that fetal malnutrition has a limited impact on male mouse offspring, yet it does influence the metabolic response to a high-fat diet in females. These findings may have implications for future early diagnostics in metabolic syndrome and for the development of sex-specific treatment regimens.

The effect of maternal hypercholesterolemia on the placenta and fetal arteries in rabbits

PURPOSE: To investigate the degree of placental permeability in dyslipidemic rabbits and the consequent vascular dysfunction in fetuses of female rabbits with high lipoprotein levels. METHODS: Fifteen adult females New Zealand White rabbits were divided into two groups. Group 1(n=5) - hypercholesterolemic diet with 0.5% cholesterol, and Group 2 (n=10) - control. On day 30, the levels of plasma lipoproteins and triglycerides were analyzed in the mothers, and the presence of collagen was analyzed in the placenta as well as in fetal coronary and aorta. Statistical analyses used the Student's t and the Mann-Whitney tests. RESULTS: Lipoprotein levels were significantly different (p=0.02 to p<0.001) in experimental and control groups. In the hypercholesterolemic group, total cholesterol levels were in average 793mg/dl; triglycerides were in average 257mg/dl; HDL-C was 48mg/dl, and LDL-C was in average 692mg/dl. The amount of collagen per micrometers square (mµ²) in samples from hypercholesterolemic animals was significantly higher than in the control group. CONCLUSIONS: The study confirmed placental permeability to lipoproteins, shown by increased amounts of collagen in fetal tissues. This alteration results in increased susceptibility to atherosclerosis in adult life, representing a risk factor for the early development of disease, which may appear even in the prenatal period.