A hypothalamic-pituitary-adrenal axis-associated neuroendocrine metabolic programmed alteration in offspring rats of IUGR induced by prenatal caffeine ingestion

Can mothers consume caffeine? The issue of early life exposure and metabolic changes in offspring

Caffeine is a substance with central and metabolic effects. Although it is recommended that its use be limited during pregnancy, many women continue to consume caffeine. Direct and indirect actions of caffeine in fetuses and newborns promote adaptive changes, according to the Developmental Origins of Health and Diseases (DOHaD) concept. In fact, epidemiological and experimental evidence reveals the impact of early caffeine exposure. Here, we reviewed these findings with an emphasis on experimental models with rodents. The similarity of human and rodent caffeine metabolism allows the comprehension of molecular mechanisms affected by prenatal caffeine exposure. Maternal caffeine intake affects the body weight and endocrine system of offspring at birth and has long-term effects on the endocrine system, liver function, glucose and lipid metabolism, the cardiac system, the reproductive system, and behavior. Interestingly, some of these effects are sex dependent. Thus, the dose of caffeine considered safe for pregnant women may not be adequate for the prenatal period.

Intrauterine developmental origin, programming mechanism, and prevention strategy of fetal-originated hypercholesterolemia

There is increasing evidence that hypercholesterolemia has an intrauterine developmental origin. However, the pathogenesis of fetal-originated is still lacking in a theoretical system, which makes its clinical early prevention and treatment difficult. It has been found that an adverse environment during pregnancy (e.g., xenobiotic exposure) may lead to changes in fetal blood cholesterol levels through changing maternal cholesterol metabolic function and/or placental cholesterol transport function and may also directly affect the liver cholesterol metabolic function of the offspring in utero and continue after birth. Adverse environmental conditions during pregnancy may also raise maternal glucocorticoid levels and promote the placental glucocorticoid barrier opening, leading to fetal overexposure to maternal glucocorticoids. Intrauterine high-glucocorticoid exposure can alter the liver cholesterol metabolism of offspring, resulting in an increased susceptibility to hypercholesterolemia after birth. Abnormal epigenetic modifications are involved in the intrauterine programming mechanism of fetal-originated hypercholesterolemia. Some interventions targeted at pregnant mothers or offspring in early life have been proposed to effectively prevent and treat the development of fetal-originated hypercholesterolemia. In this paper, the recent research progress on fetal-originated hypercholesterolemia was reviewed, with emphasis on intrauterine maternal glucocorticoid programming mechanisms, in order to provide a theoretical basis for its early clinical warning, prevention, and treatment.

The changes in adrenal developmental programming and homeostasis in offspring induced by glucocorticoids exposure during pregnancy

Clinically, synthetic glucocorticoids are often used to treat maternal and fetal related diseases, such as preterm birth and autoimmune diseases. Although its clinical efficacy is positive, it will expose the fetus to exogenous glucocorticoids. Adverse environments during pregnancy (e.g., exogenous glucocorticoids exposure, malnutrition, infection, hypoxia, and stress) can lead to fetal overexposure to endogenous maternal glucocorticoids. Basal glucocorticoids levels in utero are crucial in determining fetal tissue maturation and its postnatal fate. As the synthesis and secretion organ of glucocorticoids, the adrenal development is crucial for the growth and development of the body. Studies have found that glucocorticoids exposure during pregnancy could cause abnormal fetal adrenal development, which could last after birth or even adulthood. As the key organ of fetal-originated adult disease, the adrenal developmental programming has a profound impact on the health of offspring, which can lead to many chronic diseases in adulthood. However, the aberrant adrenal development in offspring caused by glucocorticoids exposure during pregnancy and its intrauterine programming mechanism have not been systematically clarified. Therefore, this review summarizes recent research progress on the short and long-term hazards of aberrant adrenal development induced by glucocorticoids exposure during pregnancy, which is of great significance for the analysis of aberrant adrenal development and clarify the intrauterine origin mechanism of fetal-originated adult disease.

Prenatal caffeine exposure induces autism-like behaviors in offspring under a high-fat diet via the gut microbiota-IL-17A-brain axis

Prenatal caffeine exposure (PCE) is a significant contributor to intrauterine growth retardation (IUGR) in offspring, which has been linked to an increased susceptibility to autism spectrum disorder (ASD) later in life. Additionally, a high-fat diet (HFD) has been shown to exacerbate ASD-like behaviors, but the underlying mechanisms remain unclear. In this study, we first noted in the rat model of IUGR induced by PCE that male PCE offspring exhibited typical ASD-like behaviors post-birth, in contrast to their female counterparts. The female PCE offspring demonstrated only reduced abilities in free exploration and spatial memory. Importantly, both male and female PCE offspring displayed ASD-like behaviors when exposed to HFD. We further observed that PCE + HFD offspring exhibited damaged intestinal mucus barriers and disturbed gut microbiota, resulting in an increased abundance of Escherichia coli (E. coli). The induced differentiation of colonic Th17 cells by E. coli led to an increased secretion of IL-17A, which entered the hippocampus through peripheral circulation and caused synaptic damage in hippocampal neurons, ultimately resulting in ASD development. Our strain transplantation experiment suggested that E. coli-mediated increase of IL-17A may be the core mechanism of ASD with a fetal origin. In conclusion, PCE and HFD are potential risk factors for ASD, and E. coli-mediated IL-17A may play a crucial role in fetal-originated ASD through the gut-brain axis.

Epigenetic modification impacting brain functions: Effects of physical activity, micronutrients, caffeine, toxins, and addictive substances

Changes in gene expression are involved in many brain functions. Epigenetic processes modulate gene expression by histone modification and DNA methylation or RNA-mediated processes, which is important for brain function. Consequently, epigenetic changes are also a part of brain diseases such as mental illness and addiction. Understanding the role of different factors on the brain epigenome may help us understand the function of the brain. This review discussed the effects of caffeine, lipids, addictive substances, physical activity, and pollutants on the epigenetic changes in the brain and their modulatory effects on brain function.

Microbiota-indole 3-propionic acid-brain axis mediates abnormal synaptic pruning of hippocampal microglia and susceptibility to ASD in IUGR offspring

BACKGROUND

Autism spectrum disorder (ASD) has been associated with intrauterine growth restriction (IUGR), but the underlying mechanisms are unclear.

RESULTS

We found that the IUGR rat model induced by prenatal caffeine exposure (PCE) showed ASD-like symptoms, accompanied by altered gut microbiota and reduced production of indole 3-propionic acid (IPA), a microbiota-specific metabolite and a ligand of aryl hydrocarbon receptor (AHR). IUGR children also had a reduced serum IPA level consistent with the animal model. We demonstrated that the dysregulated IPA/AHR/NF-κB signaling caused by disturbed gut microbiota mediated the hippocampal microglia hyperactivation and neuronal synapse over-pruning in the PCE-induced IUGR rats. Moreover, postnatal IPA supplementation restored the ASD-like symptoms and the underlying hippocampal lesions in the IUGR rats.

CONCLUSIONS

This study suggests that the microbiota-IPA-brain axis regulates ASD susceptibility in PCE-induced IUGR offspring, and supplementation of microbiota-derived IPA might be a promising interventional strategy for ASD with a fetal origin. Video Abstract.

Cathepsin D mediates prenatal caffeine exposure-caused NAFLD susceptibility in male rat offspring by regulating autophagy

Epidemiological evidence has revealed that non-alcoholic fatty liver disease (NAFLD) harbors an intrauterine origin. Autophagy is known to be involved in the protective mechanism in the development of adult NAFLD, but whether it engages in the occurrence of fetal-originated NAFLD remains unclear. In this study, a rat model of fetal-originated NAFLD was established by giving a high-fat diet or chronic stress after birth on prenatal caffeine exposure (PCE) male offspring. The alterations of liver morphologic analysis, lipid metabolism, and autophagy before and after birth were determined to confirm autophagy mechanism, NAFLD susceptibility, and intrauterine origin in PCE male adult offspring. Our results revealed that PCE-induced intrauterine high concentration of corticosterone exposure blocked autophagic flux by inhibiting cathepsin D expression in hepatocytes, leading to β-oxidation inhibition and lipid accumulation in the liver. Moreover, high concentration of corticosterone upregulated miR-665 by activating the glucocorticoid receptor to suppress cathepsin D, thus causing lysosomal degradation dysfunction and autophagy flux blockade. Notably, hepatic overexpression of cathepsin D could reverse PCE-induced postnatal NAFLD susceptibility in male rat offspring. This study elucidates the epigenetic programming mechanism of intrauterine autophagy-related fetal-originated NAFLD susceptibility, and identifies cathepsin D as its early intervention target, providing an experimental basis for exploring early prevention and treatment strategies for fetal-originated NAFLD.

Low H3K27 acetylation of SF1 in PBMC: a biomarker for prenatal dexamethasone exposure-caused adrenal insufficiency of steroid synthesis in male offspring

Dexamethasone is widely used to treat pregnancy disorders related to premature delivery. However, lots of researches have confirmed that prenatal dexamethasone exposure (PDE) could increase the risk of offspring multiple diseases. This study was designed to elucidate the epigenetic mechanism of adrenal developmental programming and explore its early warning marker in peripheral blood mononuclear cells (PBMC). We found the adrenal morphological and functional changes of PDE male offspring rats before and after birth, which were mainly performed as the decreased serum corticosterone concentration, steroidogenic acute regulatory (StAR) protein expression, and histone 3 lysine 27 acetylation (H3K27ac) level of steroidogenic factor 1 (SF1) promoter region and its expression. Simultaneously, the expressions of glucocorticoid receptor (GR) and histone acetylation enzyme 5 (HDAC5) in the PDE male fetal rats were increased. In vitro, dexamethasone reduced the expression of SF1, StAR, and cortisol production and still increased the expression of GR and HDAC5, the binding between GR and SF1 promoter region, and protein interaction between GR and HDAC5. GR siRNA or HDAC5 siRNA was able to reverse the above roles of dexamethasone. Furthermore, in vivo, we confirmed that H3K27ac levels of SF1 promoter region and its expression in PBMC of the PDE group were decreased before and after birth, showing a positive correlation with the same indexes in adrenal. Meanwhile, in clinical trials, we confirmed that prenatal dexamethasone application decreased H3K27ac of SF1 promoter region and its expression in neonatal PBMC. In conclusion, PDE-caused adrenal insufficiency of male offspring rats was related to adrenal GR activated by dexamethasone in uterus. The activated GR, on the one hand, increased its direct binding to SF1 promoter region to inhibit its expression, on the other hand, upregulated and recruited HDAC5 to decrease H3K27ac level of SF1 promoter region, and strengthened the inhibition of SF1 and subsequent StAR expression.

The upregulation of glutamate decarboxylase 67 against hippocampal excitability damage in male fetal rats by prenatal caffeine exposure

As a kind of xanthine alkaloid, caffeine is widely present in beverages, food, and analgesic drugs. Our previous studies have shown that prenatal caffeine exposure (PCE) can induce programmed hypersensitivity of the hypothalamic-pituitary-adrenal (HPA) axis in offspring rats, which is involved in developing many chronic adult diseases. The present study further examined the potential molecular mechanism and toxicity targets of hippocampal dysfunction, which might mediate the programmed hypersensitivity of the HPA axis in offspring. Pregnant rats were intragastrically administered with 0, 30, and 120 mg/kg/day caffeine from gestational days (GD) 9-20, and the fetal rats were extracted at GD20. Rat fetal hippocampal H19-7/IGF1R cell line was treated with caffeine, adenosine A2A receptor (A2AR) agonist (CGS-21680) or adenylate cyclase agonist (forskolin) plus caffeine. Compared with the control group, hippocampal neurons of male fetal rats by PCE displayed increased apoptosis and reduced synaptic plasticity, whereas glutamate decarboxylase 67 (GAD67) expression was increased. Moreover, the expression of A2AR was down-regulated, PCE inhibited the cAMP/PKA/CREB/BDNF/TrkB pathway. Furthermore, the results in vitro were consistent with the in vivo study. Both CGS21680 and forskolin could reverse the above alteration caused by caffeine. These results indicated that PCE inhibits the BDNF pathway and mediates the hippocampus's glutamate (Glu) excitotoxicity. The compensatory up-regulation of GAD67 unbalanced the Glu/gamma-aminobutyric acid (GABA)ergic output, leading to the impaired negative feedback to the hypothalamus and hypersensitivity of the HPA axis.

11β-hydroxysteroid dehydrogenases and biomarkers in fetal development

It is known that basal glucocorticoid levels in utero are essential for regulating fetal development and maturation, and determine the fate of later life. Recently, more and more studies suggest that adverse prenatal environments may cause abnormal maternal glucocorticoid levels in utero. 11β-hydroxysteroid dehydrogenases (11β-HSDs) are widely distributed in the target organs of glucocorticoids (GCs) and mineralocorticoids. 11β-HSDs is involved in fetal physiological and pathological development by activating or inactivating GCs. Prenatal adverse environments (including exogenous and maternal environments) can affect the expression and activity of 11β-HSDs in the placenta and fetus via multiple pathways. It induces abnormal local glucocorticoid levels in fetal multiple tissues, fetal developmental programming and homeostasis changes, and the susceptibility to various diseases after birth. We also discuss the interventions of 11β-HSDs inhibitors on fetal developmental programming and susceptibility to multiple diseases. Finally, we propose that 11β-HSD2 can be used as a molecular target for fetal developmental toxicity, while 11β-HSD1 can be regarded as an intervention target to prevent fetal-originated diseases. This review will provide a theoretical basis for the early prevention and treatment of fetal-originated diseases.

Intrauterine programming of cartilaginous 11β-HSD2 induced by corticosterone and caffeine mediated susceptibility to adult osteoarthritis

Our previous study reported that prenatal caffeine exposure (PCE) could induce chondrodysplasia and increase the susceptibility to osteoarthritis in offspring rats. However, the potential mechanisms and initiating factors remain unknown. This study aims to investigate whether 11β-HSD2, a glucocorticoid-metabolizing enzyme, is involved in the susceptibility of osteoarthritis induced by PCE and to further explore its potential mechanisms and initiating factors. Firstly, we found that PCE reduced cartilage matrix synthesis (aggrecan/Col2a1 expression) in male adult offspring rats and exhibited an osteoarthritis phenotype following chronic stress, which was associated with persistently reduced H3K9ac and H3K27ac levels at the promoter of 11β-HSD2 as well as its expression in the cartilage from fetus to adulthood. The expression of 11β-HSD2, aggrecan and Col2a1 were all decreased by corticosterone in the fetal chondrocytes, while overexpression of 11β-HSD2 could partially alleviate the decrease of matrix synthesis induced by corticosterone in vitro. Furthermore, the glucocorticoid receptor (GR) activated by glucocorticoids directly bonded to the promoter region of 11β-HSD2 to inhibit its expression. Meanwhile, the activated GR reduced the H3K9ac and H3K27ac levels of 11β-HSD2 by recruiting HDAC4 and promoting GR-HDAC4 protein interaction to inhibit the 11β-HSD2 expression. Moreover, caffeine could reduce the expression of 11β-HSD2 by inhibiting the cAMP/PKA signaling pathway but without reducing the H3K9ac and H3K27ac levels of 11β-HSD2, thereby synergistically enhancing the corticosterone effect. In conclusion, the persistently reduced H3K9ac and H3K27ac levels of 11β-HSD2 from fetus to adulthood mediated the inhibition of cartilage matrix synthesis and the increased susceptibility to osteoarthritis. This epigenetic programming change in utero was induced by glucocorticoids with synergistic effect of caffeine.

Prenatal caffeine exposure induced renal developmental toxicity and transgenerational effect in rat offspring

Epidemiological studies revealed that prenatal caffeine exposure (PCE) is associated with adverse gestational outcomes and susceptibility to chronic diseases in offspring, yet the effects of PCE on glomerulosclerosis susceptibility in adult female offspring and its intergenerational transmission remain to be further investigated. Here, we found that PCE caused fetal kidney dysplasia and glomerulosclerosis of the female offspring. Besides, the kidney of F1 offspring in PCE group exhibited the "low expressional programming of AT2R" and "GC-IGF1 programming" alteration. Intergenerational genetic studies revealed that the renal defect and GC-IGF1 programming alteration was inherited to F2 adult female offspring derived from the female germ line, but Low expression of AT2R did not extend to the F2 female offspring. Taken together, PCE caused renal dysplasia and adult glomerulosclerosis in the F1 female offspring, which might be mediated by renal AT2R low expressional programming and GC-IGF1 axis alteration. Furthermore, PCE induced transgenerational toxicity on kidney, and GC-IGF1 programming alteration might be the potential molecular mechanism. This study provided experimental evidence for the mechanism study of the intergenerational inheritance of kidney developmental toxicity caused by PCE.

Sex difference in adrenal developmental toxicity induced by dexamethasone and its intrauterine programming mechanism

Dexamethasone is widely used to treat preterm labor and related diseases. However, prenatal dexamethasone treatment (PDT) can cause multiorgan developmental toxicities in offspring. Our previous study found that the occurrence of fetal-originated diseases was associated with adrenal developmental programming alterations in offspring. Here, we investigated the effects of PDT on adrenal function in offspring and its intrauterine programming mechanism. A rat model of PDT was established to observe the alterations of adrenal steroidogenesis in offspring. Furthermore, we confirmed the sex differences of adrenal steroidogenesis and its molecular mechanism combined with in vivo and in vitro experiments. PDT caused a decrease in adrenal steroidogenic function in fetal rats, but it was decreased in males and increased in females after birth. Meanwhile, the adrenal H3K14ac level and expression of 11β-hydroxysteroid dehydrogenase 2 (11β-HSD2) in PDT offspring were decreased in males and increased in females, suggesting that 11β-HSD2 might mediate sex differences in adrenal function. We further confirmed that dexamethasone inhibited the H3K14ac level and expression of 11β-HSD2 through the GR/SP1/p300 pathway. After bilateral testectomy or ovariectomy of adult PDT offspring rats, adrenal 11β-HSD2 expression and steroidogenic function were both reduced. Using rat primary fetal adrenal cells, the differential expression of AR and ERβ was proven to be involved in regulating the sex difference in 11β-HSD2 expression. This study demonstrated the sex difference in adrenal steroidogenic function of PDT offspring after birth and elucidated a sex hormone receptor-dependent epigenetically regulating mechanism for adrenal 11β-HSD2 programming alteration.

Intrauterine endogenous high glucocorticoids program ovarian dysfunction in female offspring secondary to prenatal caffeine exposure

Ovarian dysfunction has an intrauterine origin, and prenatal caffeine exposure (PCE) could lead to abnormal follicle counts in offspring after birth. However, the effect of PCE on offspring ovarian function and its mechanism of intrauterine programming have not been reported thus far. In this study, pregnant Wistar rats were intragastrically administered caffeine (30 and 120 mg/kg·d) at gestational days 9-20 (GD9-20). Certain tests were performed on the blood, ovaries and hypothalamus of female offspring at different time points. PCE female offspring had ovarian dysfunction in adulthood compared with the control. Further results showed that in utero ovarian morphological development and estradiol synthesis were inhibited but rapidly increased during puberty in the PCE group. The histone 3 lysine 27 acetylation (H3K27ac) level of the insulin-like growth factor 1 (IGF1) promoter region and its expression were decreased in the ovary, which was due to exposure to high levels of fetal blood corticosterone, and the H3K27ac level of IGF1 and its expression shifted to increase after birth with a decrease in serum corticosterone levels. Chronic stress led to increased serum corticosterone levels in adult offspring, whereas ovarian morphological development, the H3K27ac level of IGF1 and its expression, and estradiol synthesis were significantly inhibited. Moreover, the activity of the hypothalamic-pituitary-ovarian (HPO) axis was increased in the early postnatal period of PCE offspring, and chronic stress reversed these changes. In the KGN cell line, it was found that cortisol could promote the translocation of the glucocorticoid receptor (GR) into the nucleus and upregulate histone deacetylase 10 (HDAC10) to inhibit the H3K27ac level of IGF1 and its expression and estradiol synthesis. In summary, PCE is associated with ovarian dysfunction in female adult offspring, and the potential mechanism is related to intrauterine high glucocorticoid exposure by activating the GR and recruiting HDAC10 to affect ovarian glucocorticoid-IGF1 axis programming and to inhibit estradiol synthesis.

Associations of prenatal metabolomics profiles with early childhood growth trajectories and obesity risk in African Americans: the CANDLE study

OBJECTIVE

Prenatal metabolomics profiles, providing measures of in utero nutritional and environmental exposures, may improve the prediction of childhood outcomes. We aimed to identify prenatal plasma metabolites associated with early childhood body mass index (BMI) trajectories and overweight/obesity risk in offspring.

METHODS

This study included 450 African American mother-child pairs from the Conditions Affecting Neurocognitive Development and Learning in Early Childhood Study. An untargeted metabolomics analysis was performed on the mothers' plasma samples collected during the second trimester. The children's BMI-z-score trajectories from birth to age 4 [rising-high- (9.8%), moderate- (68.2%), and low-BMI (22.0%)] and overweight/obesity status at age 4 were the main outcomes. The least absolute shrinkage and selection operator (LASSO) was used to select the prenatal metabolites associated with childhood outcomes.

RESULTS

The mothers were 24.5 years old on average at recruitment, 76.4% having education less than 12 years and 80.0% with Medicaid or Medicare. In LASSO, seven and five prenatal metabolites were associated with the BMI-z-score trajectories and overweight/obese at age 4, respectively. These metabolites are mainly from/relevant to the pathways of steroid biosynthesis, amino acid metabolism, vitamin B complex, and xenobiotics metabolism (e.g., caffeine and nicotine). The odds ratios (95% CI) associated with a one SD increase in the prenatal metabolite risk scores (MRSs) constructed from the LASSO-selected metabolites were 2.97 (1.95-4.54) and 2.03 (1.54-2.67) for children being in the rising-high-BMI trajectory group and overweight/obesity at age 4, respectively. The MRSs significantly improved the risk prediction for childhood outcomes beyond traditional prenatal risk factors. The increase (95% CI) in the area under the receiver operating characteristic curves were 0.10 (0.03-0.18) and 0.07 (0.02-0.12) for the rising-high-BMI trajectory (P = 0.005) and overweight/obesity at age 4 (P = 0.007), respectively.

CONCLUSIONS

Prenatal metabolomics profiles advanced prediction of early childhood growth trajectories and obesity risk in offspring.

Selection and verification of the combination of reference genes for RT-qPCR analysis in rat adrenal gland development

Quantitative reverse transcription polymerase chain reaction (RT-qPCR) is commonly used for gene expression analysis, and the accuracy of its results depends greatly on chosen reference genes. Adrenal gland is the core of the occurrence and development of fetal-originated adult diseases. Its dysplasia or dysfunction may increase susceptibility to adult disease, which has apparent sex differences. To explore the optimal combination of reference genes for RT-qPCR in female and male rats adrenal development, we selected seven reference genes (GAPDH, β-actin, etc.), and use RT-qPCR to detect genes expression during different stages of rats adrenal development under physiological conditions. Then we analysed data using GeNorm, NormFinder and BestKeeper to select the optimal combination of reference genes. Further, we used the intrauterine growth retardation (IUGR) model of rat caused by prenatal caffeine exposure (PCE) to verify the stability and accuracy of the selected combination of reference genes under physiological conditions. The results showed that TBP + β-actin could be the optimal combination of reference genes for fetal rat adrenals under physiological conditions, without obvious sex differences. In infancy and adolescence, the optimal combination of reference genes for adrenals had sex differences, and females were GAPDH + β-actin, while males were GAPDH + SDHA. In PCE model, the optimal combination of reference genes was consistent with physiological conditions. Using combination of reference genes to analyze target genes can improve the accuracy of the results. In summary, this study provided reliable combination of reference genes for RT-qPCR and experimental supports for researches on adrenal development.

H3K9ac of TGFβRI in human umbilical cord: a potential biomarker for evaluating cartilage differentiation and susceptibility to osteoarthritis via a two-step strategy

Background

Epidemiological investigation and our previous reports indicated that osteoarthritis had a fetal origin and was closely associated with intrauterine growth retardation (IUGR). Human Wharton’s jelly-derived mesenchymal stem cells (WJ-MSCs) could be programmable to “remember” early-life stimuli. Here, we aimed to explore an early-warning biomarker of fetal-originated adult osteoarthritis in the WJ-MSCs.

Methods

Firstly, two kinds of WJ-MSCs were applied to evaluate their chondrogenic potential in vitro through inducing chondrogenic differentiation as the first step of our strategy, one from newborns with IUGR and the other from normal newborns but treated with excessive cortisol during differentiation to simulate the excessive maternal glucocorticoid in the IUGR newborns. As for the second step of the strategy, the differentiated WJ-MSCs were treated with interleukin 1β (IL-1β) to mimic the susceptibility to osteoarthritis. Then, the expression and histone acetylation levels of transforming growth factor β (TGFβ) signaling pathway and the expression of histone deacetylases (HDACs) were quantified, with or without cortisol receptor inhibitor RU486, or HDAC4 inhibitor LMK235. Secondly, the histone acetylation and expression levels of TGFβRI were further detected in rat cartilage and human umbilical cord from IUGR individuals.

Results

Glycosaminoglycan content and the expression levels of chondrogenic genes were decreased in the WJ-MSCs from IUGR, and the expression levels of chondrogenic genes were further reduced after IL-1β treatment, while the expression levels of catabolic factors were increased. Then, serum cortisol level from IUGR individuals was found increased, and similar changes were observed in normal WJ-MSCs treated with excessive cortisol. Moreover, the decreased histone 3 lysine 9 acetylation (H3K9ac) level of TGFβRI and its expression were observed in IUGR-derived WJ-MSCs and normal WJ-MSCs treated with excessive cortisol, which could be abolished by RU486 and LMK235. At last, the decreased H3K9ac level of TGFβRI and its expression were further confirmed in the cartilage of IUGR rat offspring and human umbilical cords from IUGR newborn.

Conclusions

WJ-MSCs from IUGR individuals displayed a poor capacity of chondrogenic differentiation and an increased susceptibility to osteoarthritis-like phenotype, which was attributed to the decreased H3K9ac level of TGFβRI and its expression induced by high cortisol through GR/HDAC4. The H3K9ac of TGFβRI in human umbilical cord could be a potential early-warning biomarker for predicting neonatal cartilage dysplasia and osteoarthritis susceptibility.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-021-02234-8.

Ghrelin signalling is dysregulated in male but not female offspring in a rat model of maternal vertical sleeve gastrectomy

Bariatric surgery is the most effective and durable means of treating obesity and its comorbidities. Women make up 80% of those receiving weight loss surgery and they experience improvements in fertility. Unfortunately, bariatric surgery in the context of pregnancy is associated with complications, including growth restriction and small-for-gestational age offspring (SGA). SGA offspring have a greater risk for obesity in adulthood, although the mechanism for this SGA-induced obesity is unknown. In a rat model of vertical sleeve gastrectomy (VSG), we previously identified reductions during pregnancy in ghrelin, a stomach-derived hormone that increases appetite and induces growth hormone secretion. Here, we hypothesise that VSG offspring will have altered ghrelin signalling compared to offspring of Sham dams as a result of reduced in utero ghrelin. At postnatal day (PND)21, male and female offspring of dams that have previously received VSG have an increase in mRNA expression for the ghrelin receptor in the hypothalamus compared to Sham offspring, and the expression of GOAT is lower in females compared to males. Liver expression of endogenous ghrelin antagonist, LEAP2, is elevated at PND60 in VSG offspring. Expression of other genes in the growth hormone system (growth hormone-releasing hormone and growth hormone) were not altered. Plasma levels of total ghrelin at PND21 are also not different between VSG and Sham pups. In adult pups, 1-hour chow intake of male but not female VSG offspring given is less than Sham offspring when given 50 µg kg^-1 of exogenous ghrelin by i.p. injection. These results indicate that maternal VSG surgery has an impact on ghrelin signalling in offspring and that, as adults, male VSG offspring may be functionally less responsive to ghrelin than controls.

Articular damages in multi-generational female offspring due to prenatal caffeine exposure correlates with H3K9 deacetylation of TGFβ signaling pathway

Adverse environment during pregnancy could lead to maternal glucocorticoid overexposure in utero, and then induce the intrauterine growth retardation (IUGR) and the programmed change in cartilage development. The transforming growth factor β (TGFβ) signaling pathway plays a crucial role in the process of chondrogenesis, cartilage growth, development, maturation, and phenotype maintenance. Our previous results had shown that prenatal caffeine exposure (PCE) could result in the damaged articular cartilage in offspring rats. However, whether this change could transmit to multiple generations was still unknown. In this study, pregnant Wistar rats received either saline or caffeine (120 mg/kg, i.g.) once daily from gestational day 9-20 (GD9-20). The female offspring mated with normal male rats to generate the following generations. We obtained the articular cartilages in subsequent F1 to F3 female offspring. The H3K9 acetylation and expression of the TGFβ signaling pathway were detected; the content of the cartilage matrix was detected. The results showed that PCE reduced the H3K9 acetylation and the expression of the TGFβ signaling pathway, then reduced the extracellular matrix in F1, F2, and F3 generations. in vitro, corticosterone could induce the H3K9 deacetylation of the TGFβ signaling pathway, thus inhibiting the expression of the TGFβ signaling pathway and extracellular matrix. The overall results revealed that PCE induced a multi-generational damaged articular cartilage in female offspring rats, which was partially related to the maternal high glucocorticoid-induced H3K9 hypoacetylation of TGFβ signaling pathway.

Association of maternal caffeine intake during pregnancy with low birth weight, childhood overweight, and obesity: a meta-analysis of cohort studies

BACKGROUND

Epidemiological studies reported inconsistent results on the associations between maternal caffeine intake during pregnancy and risk of low birth weight (LBW) and childhood overweight and obesity in their offspring.

METHODS

We conducted a meta-analysis of cohort studies to quantitatively assess these associations. Pertinent studies were identified by searching PubMed and Embase through June 2019. Study-specifics risk estimates were combined using fixed effects models, or random-effects models when significant heterogeneity was detected. Dose-response analysis was modeled by using restricted cubic splines.

RESULTS

A total of 15 cohort studies, with 102,347 pregnancy women, was included in the meta-analysis. The pooled relative risk (RR) for LBW was 1.33 (95% CI: 1.12, 1.57) for mothers with the highest compared with the lowest level of caffeine intake during pregnancy, with significant heterogeneity across studies (I² = 49.3%, P = 0.032). The pooled RR was 1.07 (95% CI: 1.02, 1.11) for each 100 mg/day increase of caffeine intake. The pooled RR for childhood overweight and obesity was 1.39 (95% CI: 1.15, 1.69) for mothers with the highest compared with the lowest level of caffeine intake during pregnancy. No significant heterogeneity across studies was detected (I² = 38.9%, P = 0.179). The pooled RR was 1.31 (95% CI: 1.11, 1.55) for each 100 mg/day increase of caffeine intake. No evidence of publication bias was indicated.

CONCLUSIONS

Maternal caffeine intake during pregnancy is associated with higher risk of LBW and childhood overweight and obesity. Further studies may focus on investigating the potential mechanisms before the recommendation of complete avoidance of caffeine intake during pregnancy.

Associations of maternal caffeine intake during pregnancy with abdominal and liver fat deposition in childhood

BACKGROUND

Maternal caffeine intake during pregnancy is associated with an increased risk of childhood obesity. Studies in adults suggest that caffeine intake might also directly affect visceral and liver fat deposition, which are strong risk factors for cardio-metabolic disease.

OBJECTIVE

To assess the associations of maternal caffeine intake during pregnancy with childhood general, abdominal, and liver fat mass at 10 years of age.

METHODS

In a population-based cohort from early pregnancy onwards among 4770 mothers and children, we assessed maternal caffeine intake during pregnancy and childhood fat mass at age 10 years.

RESULTS

Compared with children whose mothers consumed <2 units of caffeine per day during pregnancy, those whose mothers consumed 4-5.9 and ≥6 units of caffeine per day had a higher body mass index, total body fat mass index, android/gynoid fat mass ratio, and abdominal subcutaneous and visceral fat mass indices. Children whose mothers consumed 4-5.9 units of caffeine per day had a higher liver fat fraction. The associations with abdominal visceral fat and liver fat persisted after taking childhood total body fat mass into account.

CONCLUSIONS

High maternal caffeine intake during pregnancy was associated with higher childhood body mass index, total body fat, abdominal visceral fat, and liver fat. The associations with childhood abdominal visceral fat and liver fat fraction were independent of childhood total body fat. This suggests differential fat accumulation in these depots, which may increase susceptibility to cardio-metabolic disease in later life.

Effects of prenatal nicotine exposure on hepatic glucose and lipid metabolism in offspring rats and its hereditability

Prenatal nicotine exposure (PNE) could induce an increased susceptibility to multiple chronic diseases in adult offspring, that mainly caused by intrauterine maternal glucocorticoid (GC) over-exposure. We investigated the changes and inheritability of hepatic glucose and lipid metabolism caused by PNE, to decipher the possible intrauterine programming mechanism. Pregnant Wistar rats were administered subcutaneously with 2 mg/kg·d nicotine from gestational day (GD) 9∼20, and second-generation (F2) were set according to the mating between control females and PNE males. The results showed that serum phenotypes and hepatic enzymes of glucose and lipid metabolism were lower in F1 fetal rats of PNE but higher in the F1 adult rats. Meanwhile, the activated states of hepatic glucocorticoid-activation system, including type 1 and type 2 11β-hydroxysteroid dehydrogenases (Hsd11b1/2), nuclear receptor subfamily 3, group C, member 1 (Nr3c1) and CCAAT enhancer binding protein α (Cebpa), were positively correlated with serum corticosterone levels but negatively correlated with the histone acetylation (H3K27ac) and expression levels of insulin-like growth factor 1 (Igf1) before and after birth. Furthermore, serum phenotypes and hepatic enzymes of glucose and lipid metabolism were lower in both F2 fetal and adult rats of PNE, which were consistent with the hepatic changes of GC-IGF1 axis and the glucocorticoid-activation system. In conclusion, PNE could lead to inheritable changes of hepatic glucose and lipid metabolism, which are related to the intrauterine programming of GC-IGF1 axis induced by the glucocorticoid-activation system.

Caffeine Intake During Pregnancy and Risk of Childhood Obesity: A Systematic Review

OBJECTIVE

This paper evaluates the association between caffeine consumption during pregnancy and overweight or obesity in the offspring.

METHODS

Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a literature search was conducted using MedLine, PubMed, CINAHL-Plus and Google Scholar databases. Inclusion criteria were cohort studies on participants with live singleton births at ≥28 weeks gestation who had consumed caffeine during pregnancy. Included were studies reporting both measurement of maternal caffeine intake and offspring anthropometric measurements. Studies reporting serum paraxanthine, a measurement of caffeine intake, were also included.

RESULTS

After final elimination, there were eight studies meeting our inclusion criteria. From these studies, we deduced that caffeine intake during pregnancy between 50 mg and <150 mg/day was associated with increased risk of overweight and obesity by excess fat deposition or increased weight, and elevated BMI per International Obesity Task Force (IOTF) criteria using a reference population. The majority of studies reported the strongest association with maternal caffeine intake during pregnancy and overweight and obesity risk beginning at ≥300 mg/day.

CONCLUSIONS AND GLOBAL HEALTH IMPLICATION

The risk of childhood overweight or obesity was associated with caffeine consumption at 50 mg/day during pregnancy with a stronger association at intakes ≥300 mg/day and higher. The current recommendation of <200 mg/day of caffeine during pregnancy is likely associated with lower risk of overweight or obesity in offspring but avoidance of the substance is recommended.

Programming changes in GLUT1 mediated the accumulation of AGEs and matrix degradation in the articular cartilage of female adult rats after prenatal caffeine exposure

Osteoarthritis is associated with intrauterine growth retardation (IUGR) and abnormal glucose metabolism. Our laboratory previously reported that prenatal caffeine exposure (PCE) can induce intrauterine maternal glucocorticoid (GC) overexposure in IUGR offspring and increase susceptibility to osteoarthritis after birth. In the present study, we demonstrated the essential role of glucose transporter 1 (GLUT1) programming changes in the increased matrix degradation of articular cartilage and susceptibility to osteoarthritis in female PCE adult offspring. In vivo, we found that PCE decreased the matrix content but did not significantly change the expression of matrix degradation-related genes in the articular cartilage of female fetal rats. The decreased expression of IGF1 and GLUT1 and the content of advanced-glycation-end-products (AGEs) were also detected. At different postnatal stages (2, 6, and 12 weeks), the cartilage matrix content decreased while the degradation-related genes expression increased in the PCE group. Meanwhile, the expression of IGF1 and GLUT1 and AGEs content in the local cartilage increased. In vitro, the expression levels of IGF1 and GLUT1 were inhibited by corticosterone but remained unchanged under caffeine treatment. Exogenous IGF1 can reverse the corticosterone-induced decrease in GLUT1 expression and promote AGEs production, while mifepristone (a glucocorticoid receptor inhibitor) reversed the corticosterone-induced low expression of IGF1 and GLUT1. Exogenous AGEs can increase the expression of inflammatory factors (IL-6 and TNF-α) and degradation-related genes, and decrease the matrix synthesis-related genes expression in chondrocyte. In conclusion, the GC-IGF1-GLUT1 axis mediated intrauterine dysplasia of articular cartilage, increased accumulation of AGEs and matrix degradation after birth in PCE female offspring, thereby increasing their susceptibility to osteoarthritis in adulthood.

Prenatal glucocorticoids exposure and fetal adrenal developmental programming

Clinically, we apply synthetic glucocorticoids to treat fetal and maternal diseases, such as premature labor and autoimmune diseases. Although its clinical efficacy is positive, the fetus will be exposed to exogenous synthetic glucocorticoids. Prenatal adverse environments (such as xenobiotics exposure, malnutrition, infection, hypoxia and stress) can cause fetuses overexposure to excessive endogenous maternal glucocorticoids. The level of glucocorticoids is the key to fetal tissue maturation and postnatal fate. A large number of studies have found that prenatal glucocorticoids exposure can lead to fetal adrenal dysplasia and dysfunction, continuing after birth and even into adulthood. As the core organ of fetal-originated adult diseases, fetal adrenal dysplasia is closely related to the susceptibility and occurrence of multiple chronic diseases, and there are also obvious gender differences. However, its intrauterine programming mechanisms have not been fully elucidated. This review summarizes recent advances in prenatal glucocorticoids exposure and fetal adrenal developmental programming alterations, which is of great significance for explaining adrenal developmental toxicity and the intrauterine origin of fetal-originated adult diseases.

Serum metabolic profile characteristics of offspring rats before and after birth caused by prenatal caffeine exposure

Epidemiological investigations have confirmed that prenatal caffeine intake could increase the incidence rate of intrauterine growth retardation (IUGR) and multiple diseases after birth. Based on liquid chromatography-mass spectrometry, we analyzed serum metabolic profiles of offspring rats before and after birth in IUGR model induced by prenatal caffeine exposure (PCE). We discovered that differential metabolites in PCE fetuses mainly manifested as amino acids and lipid metabolism. In adulthood, PCE offspring showed less and inconsistent types of differential metabolites compared to those in utero, which still exhibited gender differences. The main differential metabolites induced by PCE, including phospholipids, platelet-activating factor, arachidonic acid, bile acid, sphingosine-1-phosphoric acid, indoxyl sulfuric acid, and cortexolone, may participate in the pathological and physiological processes of organ toxicities. This study demonstrated the short- and long-term developmental toxicity and gender differences of caffeine, providing new ideas for exploring the early warning and drug intervention targets of IUGR offspring.

Prenatal ethanol exposure-induced a low level of foetal blood cholesterol and its mechanism of IGF1-related placental cholesterol transport dysfunction

Clinical researches showed that intrauterine growth retardation (IUGR) foetus had decreased blood cholesterol levels. The present study aimed to confirm that prenatal ethanol exposure (PEE) caused decreased blood cholesterol levels in IUGR foetal rats and elucidate its placental mechanism. Pregnant Wistar rats were intragastrically administrated with ethanol (4 g/kg.d) on gestational days 9-20 (GD9-20). in vivo, PEE increased the levels of total cholesterol (TCH), high-density lipoprotein-cholesterol (HDL-C) and low-density lipoprotein-cholesterol (LDL-C) in maternal serum, whereas decreased them in both female and male foetal serum. Moreover, the expression of cholesterol transport genes, scavenger receptor class B type 1 (SCARB1), low-density lipoprotein receptor (LDLR), ATP binding cassette subfamily A member 1 (ABCA1) and ATP binding cassette subfamily G member 1 (ABCG1) was reduced in female and male placentas in the PEE group. Meanwhile, the proliferation decreased and the apoptosis increased in female and male placentas, and the insulin like growth factor 1 (IGF1) signal pathway was inhibited. in vitro, after being treated with ethanol (15, 30, 60, 120 mM) for 72 h, the expression of cholesterol transport genes was decreased, the apoptosis was increased, the proliferation was decreased and the IGF1 signal pathway was inhibited in BeWo cells, whereas exogenous IGF1 reversed these changes. In conclusion, by inhibiting the IGF1 signal pathway in placentas, PEE induced apoptosis and inhibited proliferation, thus decreased the cholesterol transport in placentas, and eventually leading to low blood cholesterol levels in foetal rats.

Maternal, but not paternal or grandparental, caffeine intake is associated with childhood obesity and adiposity: The Lifeways Cross-Generation Cohort Study

BACKGROUND

Maternal caffeine intake is associated with adverse birth outcomes, but its long-term influence on offspring adiposity outcomes is not well studied. Furthermore, few studies have investigated paternal and grandparental caffeine intake in relation to offspring outcomes.

OBJECTIVE

To study the associations between maternal, paternal, and grandparental caffeine intake and offspring childhood adiposity.

DESIGN

The core study sample consists of 558 mother-child pairs from the Lifeways Study. Caffeine intake was derived from relevant food items in a self-administered validated food frequency questionnaire in early pregnancy. Children's body mass index (BMI) and waist circumference (WC) were measured at 5- and 9-y follow-up. Childhood overall and central obesity were defined as age- and sex-specific BMI z-score > International Obesity Task Force cut-off and WC z-score > 90th percentile, respectively. Multiple linear and logistic regressions were used to assess associations.

RESULTS

Study mothers had a mean age of 30.8 y and a mean prepregnancy BMI (kg/m2) of 23.7. In adjusted models, maternal caffeine intake was associated with a higher offspring BMI z-score [β (95% CI): 0.13 (0.06, 0.21) for year 5 and 0.17 (0.04, 0.29) for year 9; per 100 mg/d increment in maternal caffeine intake], WC z-score [β (95% CI): 0.09 (0.01, 0.17) for year 5 and 0.19 (0.05, 0.32) for year 9], and a higher risk of offspring overall obesity [OR (95% CI): 1.32 (1.11, 1.57) for year 5 and 1.44 (1.10, 1.88) for year 9] and central obesity [1.28 (1.02, 1.60) for year 5 and 1.62 (1.12, 2.34) for year 9]. The influence was stronger for coffee caffeine than tea caffeine. No consistent associations were observed for paternal and grandparental caffeine intake.

CONCLUSIONS

Maternal antenatal, but not paternal or grandparental, caffeine intake is associated with higher offspring adiposity and obesity risk at age 5 and 9 y, with stronger associations observed for coffee caffeine. This prospective observational study was registered at the ISRCTN Registry as ISRCTN16537904.

Caffeine programs hepatic SIRT1-related cholesterol synthesis and hypercholesterolemia via A2AR/cAMP/PKA pathway in adult male offspring rats

Clinical and animal studies have indicated that hypercholesterolemia has intrauterine developmental origin. Our previous studies showed that prenatal caffeine exposure (PCE) increased the serum total cholesterol (TCH) levels in adult offspring rats. This study investigates the intrauterine programming mechanism of PCE male offspring rats susceptible to adult hypercholesterolemia. Pregnant Wistar rats were intragastrically administered caffeine (30, 60, and 120 mg/kg∙d) from gestational days (GD) 9 to 20. Male offspring were sacrificed under anesthesia at GD20 and postnatal week (PW) 12, and the serum and liver were collected. The effects of caffeine (0-100 μM, 24 h) on the expression of cholesterol synthesis related genes and their epigenetic mechanisms were confirmed in L02 cells. The results showed that PCE induced higher levels of serum TCH, LDL-C and higher ratios of TCH/HDL-C and LDL-C/HDL-C. Furthermore, the high levels of histone acetylation (via H3K14ac and H3K27ac) and the expression of genes (Srebf2, Hmgcr, Hmgcs1) were responsible for cholesterol synthesis. The results of PCE offspring in utero and the data in vitro exhibited similar changes, and accompanied by the reduced expression of adenosine A2A receptor (A2AR), cyclic adenosine monophosphate (cAMP), sirtuin1 and protein kinase A (PKA). These changes could be reversed by A2AR agonist (CGS-21680), cAMP agonist (forskolin) and sirtuin1 agonist (resveratrol). Therefore, our results confirmed that caffeine could enhance histone acetylation and expression levels of genes responsible for cholesterol synthesis via inhibiting the A2AR/cAMP/PKA pathway and down-regulating sirtuin1, which continued throughout adulthood and elevated hepatic cholesterol synthesis and hypercholesterolemia in the male offspring rats.

Prenatal caffeine exposure increases the susceptibility to non-alcoholic fatty liver disease in female offspring rats via activation of GR-C/EBPα-SIRT1 pathway

This study aimed to evaluate female adult offspring induced by prenatal caffeine exposure (PCE) are susceptible to non-alcoholic fatty liver disease (NAFLD) and to explore the underlying programming mechanisms. Pregnant rats were intragastrically administered caffeine (30, 60, and 120 mg/kg.d) on gestational day (GD) 9-20. The female adult offspring were randomly divided into three groups: offspring without or with chronic stress during postnatal week (PW) 10-12 and PW28 offspring. Results showed that PW28 PCE female offspring had a higher hepatic triglyceride content and Kleiner scores, accompanied by elevated serum corticosterone levels. Moreover, the expression levels of hepatic glucocorticoid receptor (GR), CCAAT enhancer binding protein α (C/EBPα), fatty acid synthetase (FASN) and the transcription factor-sterol regulatory element binding protein 1c (SREBP1c) were increased, but SIRT1 expression was decreased. The fetal rats and PW12 offspring with chronic stress exhibited similar changes as PW28 offspring, accompanied by increased levels of H3K14ac and H3K27ac in the SREBP1c and FASN gene promoters. These effects were also observed by treating L02 cells with cortisol and were partially reversed by GR or C/EBPα siRNA or treatment with the SIRT1 agonist resveratrol. Taken together, PCE-induced high glucocorticoids levels enhanced histone modifications and expression of SREBP1c and FASN via activation of the GR-C/EBPα-SIRT1 pathway in utero. This enhanced female fetal hepatic triglyceride synthesis and continued throughout postnatal and adult life, increasing the susceptibility to adult NAFLD.

Age-Characteristic Changes of Glucose Metabolism, Pancreatic Morphology and Function in Male Offspring Rats Induced by Prenatal Ethanol Exposure

Intrauterine growth restricted offspring suffer from abnormal glucose homeostasis and β cell dysfunction. In this study, we observed the dynamic changes of glucose metabolic phenotype, pancreatic morphology, and insulin synthesis in prenatal ethanol exposure (PEE) male offspring rats, and to explore the potential intrauterine programming mechanism of the glucocorticoid-insulin-like growth factor 1 (GC-IGF1) axis. Ethanol (4 g/kg·d) was administered through oral gavage during gestational day (GD) 9-20. Serum glucose and insulin levels, pancreatic β cell mass, and expression of glucocorticoid receptor (GR), IGF1 and insulin were determined on GD20, postnatal week (PW) 6, PW12 with/without chronic stress (CS), and PW24, respectively. Both intraperitoneal glucose and insulin tolerance tests were conducted at PW12 and PW24. Results showed that the serum glucose and insulin levels as well as pancreatic β cell mass were reduced on GD20 in PEE males compared with the controls, while pancreatic GR expression was enhanced but IGF1 and INS1/2 expression were suppressed. After birth, compared with the controls, β cell mass in the PEE males was initially decreased at PW6 and gradually recovered from PW12 to PW24, which was accompanied by increased serum glucose/insulin levels and insulin resistance index (IRI) at PW6 and decreased serum glucose contents at PW12, as well as unchanged serum glucose/insulin concentrations at PW24. In addition, both improved glucose tolerance and impaired insulin sensitivity of the PEE males at PW12 were inversed at PW24. Moreover, at PW6 and PW12, pancreatic GR expression in the PEE group was decreased, while IGF1 expression was reversely increased, resulting in a compensatory increase of insulin expression. Moreover, CS induced pancreatic GR activation and inhibited IGF1 expression, resulting in impaired insulin biosynthesis. Conclusively, the above changes were associated with age and the intrauterine programming alteration of GC-IGF1 axis may be involved in prenatal and postnatal pancreatic dysplasia and impaired insulin biosynthesis in PEE male offspring.

Glucocorticoid-activation system mediated glucocorticoid-insulin-like growth factor 1 (GC-IGF1) axis programming alteration of adrenal dysfunction induced by prenatal caffeine exposure

Glucocorticoids play a major factor in fetal maturation and fate decision after birth. We have previously demonstrated that prenatal caffeine exposure (PCE) resulted in adrenal dysplasia. However, its molecular mechanism has not been clarified. In the present study, a rat model of intrauterine growth retardation (IUGR) was established by PCE, and offspring were sacrificed. Moreover, NCI-H295 A cells were used to confirm glucocorticoid-related molecular mechanism. Results showed that PCE fetal weight decreased, and the IUGR rate increased, while serum corticosterone levels increased but insulin-like growth factor 1 (IGF1) levels decreased. Fetal adrenals exhibited an activated glucocorticoid-activation system, and the downregulated expression of IGF1 signal pathway and steroidal synthetases. For adult rats, there was no significant change in the glucocorticoid-activation system in the PCE group, the IGF1 signal pathway showed increased trend, and the expression levels of adrenal steroidal synthetases were close to normal. The data in vitro showed that the cortisol of 1200 nM can inhibit the expression of adrenocortical cell steroidal synthetases and IGF1 signal pathway when compared with the control. Meanwhile, the glucocorticoid-activation system was activated while GR inhibitor mifepristone can reverse the effect of cortisol. Furthermore, cortisol can also promote GR into the nucleus after its activation. Based on these findings, we speculated that high concentrations of glucocorticoid in utero led to GR in the nucleus through its activation and then inhibited the IGF1 signaling pathway by activating the glucocorticoid-activation system, which could further downregulate steroid synthesis.

Influencing factors, underlying mechanism and interactions affecting hypercholesterolemia in adult offspring with caffeine exposure during pregnancy

Epidemiological surveys suggest that adult hypercholesterolemia has an intrauterine origin and exhibits gender differences. Our previous study demonstrated that adult rats with intrauterine growth retardation (IUGR) offspring rats induced by prenatal caffeine exposure (PCE) had a higher serum total cholesterol (TCH) level. In this study, we aimed to analyze the influencing factors, underlying mechanism and interactions affecting hypercholesterolemia in adult offspring with caffeine exposure during pregnancy. Pregnant rats were administered caffeine (120 mg/kg d) from gestational day 11 until delivery. Offspring rats fed a normal diet or a high-fat diet (HFD) were euthanized at postnatal week 24, and blood and liver samples were collected. The results showed that PCE could increase the serum levels of TCH and low-density lipoprotein-cholesterol (LDL-C), and the hepatic expression of HMG CoA reductase (HMGCR) and apolipoprotein B (ApoB), but decreased the high-density lipoprotein-cholesterol (HDL-C) level and the hepatic expression of scavenger receptor B1 (SR-B1) and LDL receptor (LDLR). Furthermore, PCE, HFD and gender interact with each other to influence the serum cholesterol phenotype and expression of hepatic cholesterol metabolic genes. These results suggest that the hypercholesterolemia in adult offspring rats induced by PCE mainly resulted from enhanced synthesis and the weakened reverse transport of cholesterol in the liver, furthermore HFD could aggravate this effect, which is caused by hepatic cholesterol metabolic disorders. Moreover, cholesterol metabolism in female rats was more sensitive to neuroendocrine changes and HFD than that in males. This study confirmed the influencing factors (such as a HFD and female gender) of hypercholesterolemia in IUGR offspring providing theoretical and experimental bases for the effective prevention of fetal-originated hypercholesterolemia.

Intrauterine programming mechanism for hypercholesterolemia in prenatal caffeine-exposed female adult rat offspring

Clinical and animal studies have indicated that hypercholesterolemia and its associated diseases have intrauterine developmental origins. Our previous studies showed that prenatal caffeine exposure (PCE) led to fetal overexposure to maternal glucocorticoids (GCs) and increased serum total cholesterol levels in adult rat offspring. This study further confirms the intrauterine programming of PCE-induced hypercholesterolemia in female adult rat offspring. Pregnant Wistar rats were intragastrically administered caffeine (30, 60, and 120 mg/kg/d) from gestational day (GD)9 to 20. Female rat offspring were euthanized at GD20 and postnatal wk 12; several adult rat offspring were additionally subjected to ice-water swimming stimulation to induce chronic stress prior to death. The effects of GCs on cholesterol metabolism and epigenetic regulation were verified using the L02 cell line. The results showed that PCE induced hypercholesterolemia in adult offspring, which manifested as significantly higher levels of serum total cholesterol and LDL cholesterol (LDL-C) as well as higher ratios of LDL-C/HDL cholesterol. We further found that the cholesterol levels were increased in fetal livers but were decreased in fetal blood, accompanied by increased maternal blood cholesterol levels and reduced placental cholesterol transport. Furthermore, analysis of PCE offspring in the uterus and in a postnatal basal/chronic stress state and the results of in vitro experiments showed that hepatic cholesterol metabolism underwent GC-dependent changes and was associated with cholesterol synthase via abnormalities in 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) histone acetylation. We concluded that, to compensate for intrauterine placentally derived decreases in fetal blood cholesterol levels, high intrauterine GC levels activated fetal hepatic CCAAT enhancer binding protein α signaling and down-regulated Sirtuin1 expression, which mediated the high levels of histone acetylation ( via H3K9ac and H3K14ac) and expression of HMGCR. This GC-dependent cholesterol metabolism programming effect was sustained through adulthood, leading to the occurrence of hypercholesterolemia.-Xu, D., Luo, H. W., Hu, W., Hu, S. W., Yuan, C., Wang, G. H., Zhang, L., Yu, H., Magdalou, J., Chen, L. B., Wang, H. Intrauterine programming mechanism for hypercholesterolemia in prenatal caffeine-exposed female adult rat offspring.

Maternal caffeine intake during pregnancy and childhood growth and overweight: results from a large Norwegian prospective observational cohort study

OBJECTIVES

To study the association between maternal caffeine intake during pregnancy and the child's weight gain and overweight risk up to 8 years.

DESIGN

Prospective nationwide pregnancy cohort.

SETTING

The Norwegian Mother and Child Cohort Study.

PARTICIPANTS

A total of 50 943 mothers recruited from 2002 to 2008 and their children, after singleton pregnancies, with information about average caffeine intake assessed at mid-pregnancy.

OUTCOME MEASURE

Child's body size information at 11 age points from 6 weeks to 8 years. We defined excess growth in infancy as a WHO weight gain z-score of >0.67 from birth to age 1 year, and overweight according to the International Obesity Task Force. We used a growth model to assess individual growth trajectories.

RESULTS

Compared with pregnant women with low caffeine intake (<50 mg/day, 46%), women with average (50-199 mg/day, 44%), high (≥200-299 mg/day, 7%) and very high (≥300 mg/day, 3%) caffeine intakes had an increased risk of their child experiencing excess growth in infancy, after adjustment for confounders (OR=1.15, 95% CI 1.09 to 1.22, OR=1.30, 95% CI 1.16 to 1.45, OR=1.66, 95% CI 1.42 to 1.93, respectively). In utero exposure to any caffeine was associated with higher risk of overweight at age 3 years and 5 years, while the association persisted at 8 years, only for very high exposures. Any caffeine intake was associated with increased body mass index from infancy to childhood. Children prenatally exposed to caffeine intake >200 mg/day had consistently higher weight. Very high caffeine exposures were associated with higher weight gain velocity from infancy to age 8 years.

CONCLUSION

Any caffeine consumption during pregnancy is associated with a higher risk of excess infant growth and of childhood overweight, mainly at preschool ages. Maternal caffeine intake may modify the overall weight growth trajectory of the child from birth to 8 years. This study adds supporting evidence for the current advice to reduce caffeine intake during pregnancy.

IGF1/MAPK/ERK signaling pathway-mediated programming alterations of adrenal cortex cell proliferation by prenatal caffeine exposure in male offspring rats

Our previous study proposed a glucocorticoid-insulin-like growth factor 1 (GC-IGF1) axis programming mechanism for prenatal caffeine exposure (PCE)-induced adrenal developmental dysfunction. Here, we focused on PCE-induced cell proliferation changes of the adrenal cortex in male offspring rats before and after birth and clarified the intrauterine programming mechanism. On gestational day (GD) 20, the PCE group had an elevated serum corticosterone level reduced fetal bodyweight, maximum adrenal sectional area, and elevated adrenal corticosterone and aldosterone contents. However, in postnatal week (PW) 6, the serum corticosterone level was decreased, and the bodyweight, with catch-up growth, adrenal cortex maximum cross-sectional area and aldosterone content were relatively increased, while the adrenal corticosterone content was lower. On GD20, the expression of adrenal IGF1, IGF1R and proliferating cell nuclear antigen (PCNA) were decreased, while the expression of these factors at PW6 were increased in the PCE group. Fetal adrenal gene chip analysis suggested that the mitogen-activated protein kinase/extracellular regulated protein kinase (MAPK/ERK) signal pathway was suppressed in the PCE group. Moreover, in the rat primary adrenal cells, corticosterone (rather than caffeine) was shown to significantly inhibit cell proliferation, IGF1 and PCNA expression, and ERK phosphorylation, which could be reversed by exogenous IGF1. Meanwhile, the effects of exogenous IGF1 were reversed by the ERK pathway inhibitor (PD184161). In conclusion, PCE could induce programming alterations in adrenal cortical cell proliferation before and after birth in male offspring rats. The underlying mechanism is associated with the inhibition of fetal adrenal IGF1-related MAPK/ERK signaling pathway caused by high glucocorticoid levels.

High-fat diet and chronic stress aggravate adrenal function abnormality induced by prenatal caffeine exposure in male offspring rats

We previously demonstrated thatprenatal caffeine exposure (PCE) suppressed fetal adrenal steroidogenesis and resulted in developmental programming changes in offspring rats. However, whether these changes play a role in adrenal corticosterone synthesis under high-fat diet (HFD) and unpredictable chronic stress (UCS) remains unknown. In present study, rat model was established by PCE (120 mg/kg.d), and male offspring were provided normal diet or HFD after weaning. At postnatal week 21, several rats fed HFD were exposed to UCS for 3 weeks and sacrificed. The results showed that compared with the corresponding control group, the serum corticosterone levels and adrenal steroid synthetase expression of the PCE offspring without UCS were reduced. Moreover, the glucocorticoid (GC)-activation system was inhibited, and insulin-like growth factor 1 (IGF1) signaling pathway expression was increased. With UCS exposure in the PCE offspring, serum corticosterone levels and adrenal steroid synthetase expression were increased, the activity of GC-activation system was enhanced, and adrenal IGF1 signaling pathway expression was decreased. Based on these findings, PCE induced adrenal hypersensitivity in adult male offspring rats, as shown by the reduced corticosterone levels under HFD conditions but significantly enhanced corticosterone levels with UCS, in which GC-IGF1 axis programming alteration may play an important role.

Maternal Glucocorticoid Elevation and Associated Fetal Thymocyte Apoptosis are Involved in Immune Disorders of Prenatal Caffeine Exposed Offspring Mice

Our previous study showed that prenatal caffeine exposure (PCE) could induce intrauterine growth retardation (IUGR) and glucocorticoid elevation in the fetus. Researchers suggested that IUGR is a risk factor for T helper cell (Th)1/Th2 deviation. However, whether PCE can induce these immune disorders and the underlying mechanisms of that induction remain unknown. This study aimed to observe the effects of PCE on the Th1/Th2 balance in offspring and further explore the developmental origin mechanisms from the perspective of glucocorticoid overexposure-induced thymocyte apoptosis. An IUGR model was established by caffeine administration from gestational day (GD) 9 to GD 18, and the offspring were immunized on postnatal day (PND) 42. The results show that maternal glucocorticoid overexposure increased fetal thymocyte apoptosis by activating both the Fas-mediated and the Bim-regulated apoptotic pathways. After birth, accelerated thymocyte apoptosis and Th1 suppression were also found in the PCE offspring at PND 14 and PND 49. Moreover, the PCE offspring showed immune disorders after immunization, manifesting as increased IgG1/IgG2a ratio and IL-4 production in the serum. In conclusion, PCE could induce fetal overexposure to maternal glucocorticoids and increase thymocyte apoptosis, which could persist into postnatal life and be implicated in Th1 inhibition and further immune disorders.

Interaction between maternal caffeine intake during pregnancy and CYP1A2 C164A polymorphism affects infant birth size in the Hokkaido study

BackgroundCaffeine, 1,3,7-trimethylxanthine, is widely consumed by women of reproductive age. Although caffeine has been proposed to inhibit fetal growth, previous studies on the effects of caffeine on infant birth size have yielded inconsistent findings. This inconsistency may result from failure to account for individual differences in caffeine metabolism related to polymorphisms in the gene for CYP1A2, the major caffeine-metabolizing enzyme.MethodsFive hundred fourteen Japanese women participated in a prospective cohort study in Sapporo, Japan, from 2002 to 2005, and 476 mother-child pairs were included for final analysis.ResultsCaffeine intake was not significantly associated with mean infant birth size. When caffeine intake and CYP1A2 C164A genotype were considered together, women with the AA genotype and caffeine intake of ≥300 mg per day had a mean reduction in infant birth head circumference of 0.8 cm relative to the reference group after adjusting for confounding factors. In a subgroup analysis, only nonsmokers with the AA genotype and caffeine intake of ≥300 mg per day had infants with decreased birth weight (mean reduction, 277 g) and birth head circumference (mean reduction, 1.0 cm).ConclusionNonsmokers who rapidly metabolize caffeine may be at increased risk for having infants with decreased birth size when consuming ≥300 mg of caffeine per day.

Maternal caffeine intake during pregnancy, early growth, and body fat distribution at school age

OBJECTIVE

The associations of maternal caffeine intake during pregnancy with offspring growth patterns and body fat and insulin levels at school age were examined.

METHODS

In a population-based birth cohort among 7,857 mothers and their children, maternal caffeine intake during pregnancy was assessed by questionnaires. Growth characteristics were measured from birth onward. At 6 years, body fat and insulin levels were measured.

RESULTS

Compared to children whose mothers consumed <2 units of caffeine per day during pregnancy (1 unit of caffeine is equivalent to 1 cup of coffee (90 mg caffeine)), those whose mothers consumed ≥6 units of caffeine per day tended to have a lower weight at birth, higher weight gain from birth to 6 years, and higher body mass index from 6 months to 6 years. Both children whose mothers consumed 4-5.9 and ≥6 units of caffeine per day during pregnancy tended to have a higher childhood body mass index and total body fat mass. Only children whose mothers consumed ≥6 units of caffeine per day had a higher android/gynoid fat mass ratio.

CONCLUSIONS

These results suggest that high levels of maternal caffeine intake during pregnancy are associated with adverse offspring growth patterns and childhood body fat distribution.

Prenatal caffeine exposure-induced adrenal developmental abnormality in male offspring rats and its possible intrauterine programming mechanisms

Glucocorticoid (GC) is a major factor for fetal tissue maturation and fate decision after birth. We previously demonstrated that prenatal caffeine exposure (PCE) suppressed fetal adrenal steroidogenesis and resulted in adrenal dysplasia. However, whether these changes play a role until adulthood and its intrauterine programming mechanisms remain unknown. In the present study, a rat model of intrauterine growth retardation (IUGR) was established by PCE, male fetuses and adult offspring were sacrificed at postnatal day (PD) 1, PD7, PD35, PD100 and PD168, respectively. Results showed that the PCE fetal weight decreased and the IUGR rate increased, while the serum corticosterone (CORT) level increased but the insulin-like growth factor 1 (IGF1) level decreased. Fetal adrenal exhibited an enhanced GC-activation system (11β-hydroxysteroid dehydrogenases/corticoid receptors/CCAAT/enhancer binding proteins), an inhibited IGF1 pathway and steroid synthesis function. After birth, the serum CORT levels in the PCE offspring were increased in the early period followed by falling in the later stage, while the serum IGF1 level change was the opposite and was accompanied by an obvious catch-up growth. Furthermore, the adrenal GC-activation system was inhibited but the IGF1 signaling pathway was enhanced, resulting in a compensatory increase of adrenal steroidogenesis, and the expression of steroidal synthetase was consistent with that of the IGF1 signaling pathway. Based on these findings, we proposed "two-programming mechanisms" for PCE-induced adrenal abnormality: the "first programming" mechanism is a lower function of adrenal steroidogenesis, and prenatal and postnatal adrenal structural and functional abnormalities triggered by the intrauterine GC-IGF1 axis programming-mediated by the GC-activation system that acts as "the second programming" mechanism.

Prenatal caffeine exposure induces a poor quality of articular cartilage in male adult offspring rats via cholesterol accumulation in cartilage

Epidemiological investigations indicate that osteoarthritis is associated with intrauterine growth retardation (IUGR) and abnormal cholesterol metabolism. Our previous studies showed that prenatal caffeine exposure (PCE) induced chondrogenesis retardation in IUGR offspring rats. The current study sought to investigate the effects of PCE on male IUGR offspring rats’ articular cartilage, and the mechanisms associated with abnormal cholesterol metabolism. Based on the results from both male fetal and adult fed a high-fat diet (HFD) studies of rats that experienced PCE (120 mg/kg.d), the results showed a poor quality of articular cartilage and cholesterol accumulation in the adult PCE group. Meanwhile, the serum total cholesterol and low-density lipoprotein-cholesterol concentrations were increased in adult PCE offspring. We also observed lower expression of insulin-like growth factor1 (IGF1) and impaired cholesterol efflux in adult articular cartilage. Furthermore, the expression of cartilage functional genes, components of the IGF1 signaling pathway and cholesterol efflux pathway related genes were decreased in PCE fetal cartilage. In conclusion, PCE induced a poor quality of articular cartilage in male adult offspring fed a HFD. This finding was shown to be due to cholesterol accumulation in the cartilage, which may have resulted from intrauterine reduced activity of the IGF1 signaling pathway.