Maternal betaine supplementation in rats induces intergenerational changes in hepatic IGF-1 expression and DNA methylation

Parental betaine supplementation promotes gosling growth with epigenetic modulation of IGF gene family in the liver

Betaine is widely used as a feed additive in the chicken industry to promote laying performance and growth performance, yet it is unknown whether betaine can be used in geese to improve the laying performance of goose breeders and the growth traits of offspring goslings. In this study, laying goose breeders at 39 wk of age were fed basal (Control, CON) or betaine-supplemented diets at low (2.5 g/kg, LBT) or high (5 g/kg, HBT) levels for 7 wk, and the breeder eggs laid in the last week were collected for incubation. Offspring goslings were examined at 35 and 63 d of age. The laying rate tended to be increased (P = 0.065), and the feed efficiency of the breeders was improved by betaine supplementation, while the average daily gain of the offspring goslings was significantly increased (P < 0.05). Concentrations of insulin-like growth factor 2 (IGF-2) in serum and liver were significantly increased in the HBT group (P < 0.05), with age-dependent alterations of serum T3 levels. Concurrently, hepatic mRNA expression of the IGF gene family was significantly increased in goslings derived from betaine-treated breeders (P < 0.05). A higher ratio of proliferating cell nuclear antigen (PCNA)-immunopositive nuclei was found in the liver sections of the HBT group, which was confirmed by significantly upregulated hepatic expression of PCNA mRNA and protein (P < 0.05). Moreover, hepatic expression of thyroxine deiodinase type 1 (Dio1) and thyroid hormone receptor β (TRβ) was also significantly upregulated in goslings of the HBT group (P < 0.05). These changes were associated with significantly higher levels of global DNA 5-mC methylation, together with increased expression of methyl transfer genes (P < 0.05), including betaine-homocysteine methyltransferase (BHMT), glycine N-methyltransferase (GNMT), and DNA (cytosine-5-)-methyltransferase 1 (DNMT1). The promoter regions of IGF-2 genes, as well as the predicted TRβ binding site on the IGF-2 gene, were significantly hypomethylated (P < 0.05). These results indicate that gosling growth can be improved by dietary betaine supplementation in goose breeders via epigenetic modulation of the IGF gene family, especially IGF-2, in the liver.

Integrated Multi-Omics Analysis Reveals the Effect of Maternal Gestational Diabetes on Fetal Mouse Hippocampi

Growing evidence suggests that adverse intrauterine environments could affect the long-term health of offspring. Recent evidence indicates that gestational diabetes mellitus (GDM) is associated with neurocognitive changes in offspring. However, the mechanism remains unclear. Using a GDM mouse model, we collected hippocampi, the structure critical to cognitive processes, for electron microscopy, methylome and transcriptome analyses. Reduced representation bisulfite sequencing (RRBS) and RNA-seq in the GDM fetal hippocampi showed altered methylated modification and differentially expressed genes enriched in common pathways involved in neural synapse organization and signal transmission. We further collected fetal mice brains for metabolome analysis and found that in GDM fetal brains, the metabolites displayed significant changes, in addition to directly inducing cognitive dysfunction, some of which are important to methylation status such as betaine, fumaric acid, L-methionine, succinic acid, 5-methyltetrahydrofolic acid, and S-adenosylmethionine (SAM). These results suggest that GDM affects metabolites in fetal mice brains and further affects hippocampal DNA methylation and gene regulation involved in cognition, which is a potential mechanism for the adverse neurocognitive effects of GDM in offspring.

Preventive and therapeutic role of betaine in liver disease: A review on molecular mechanisms

Betaine is a kind of water-soluble quaternary amine-type alkaloid widely existing in food, such as wheat germ, beet, spinach, shrimp and wolfberry. As an important methyl donor and osmotic pressure regulator in human body, betaine plays an important role in a variety of physiological activities. In recent years, a large number of literatures have shown that betaine has good preventive and therapeutic effects on many liver diseases, including chemical or drug-induced liver injury, nonalcoholic fatty liver disease, alcoholic fatty liver disease, liver fibrosis, hepatitis B and hepatitis C. Therefore, by searching the databases of Web of Science, PubMed, SciFinder and CNKI, this paper has summarized the molecular mechanisms of betaine in improving liver diseases. The results show that the improvement of liver diseases by betaine is closely related to a variety of molecular mechanisms, including inhibition of inflammatory response, improvement of insulin resistance, reduction of endoplasmic reticulum stress, alleviation of liver oxidative stress, increase of autophagy, remodeling of intestinal flora and regulation of epigenetic modification. More importantly, nuclear transcription factor kappa (NF-κB), AMP-activated protein kinase (AMPK), peroxisome proliferator-activated receptor α/γ (PPAR-α/γ), liver X receptor α (LXRα), protein kinase B (Akt), toll-like receptor 4 (TLR4) and cysteinyl aspartate specific proteinase-3 (Caspase-3) signaling pathways are considered as important molecular targets for betaine to improve liver diseases. These important findings will provide a direction and basis for further exploring the pathogenesis of various liver diseases and tapping the potential of betaine in the clinical treatment.

Development of plasma functionalized polypropylene wound dressing for betaine hydrochloride controlled drug delivery on diabetic wounds

Diabetes Mellitus is one of the most worrying issues among illnesses, and its chronic subsequences almost refer to inflammations and infections. The loading and local release of antioxidants to wounds may decrease inflammations. However, the low wettability of PolyPropylene (PP) restricts the drug from loading. So, to increase the adhesion of PP for loading an optimum amount of Betaine Hydrochloride (BET), plasma has been applied in two steps of functionalization and polymerization, which has been confirmed with FE-SEM, ATR-FTIR, and EDX. The new chemistry of the surface led to almost 80% of BET loaded. The drug-releasing ratio studied by HPLC approved the presence of a PEG-like layer, which was coated by polymerization of tetraglyme. To evaluate the wound healing potential of the application of PP meshes treated by plasma, 72 Wistar rats were subdivided into four groups. The skin injury site was removed and underwent biomechanical tests, stereological analysis, and RNA extraction. The results showed a significant improvement in the polymerized scaffold containing BET for skin injury. The present study suggests that the use of a modified PP mesh can induce tissue regeneration and accelerate wound healing at the skin injury site.

Maternal Methyl-Donor Micronutrient Supplementation During Pregnancy Promotes Skeletal Muscle Differentiation and Maturity in Newborn and Weaning Pigs

Adequate maternal methyl-donor micronutrient (MET) intake is an important determinant of the organ development and metabolic renovation of offspring. The mechanism involved in skeletal myogenesis and the effect of MET supplementation during pregnancy on the maternal body remain unclear. Thus, this study aimed to investigate the potential effect of methyl donor micronutrients (MET) on skeletal muscle development and metabolism in offspring using pig models. Forty-three Duroc × Erhualian gilts were assigned to two dietary groups during gestation: control diet (CON) and CON diet supplemented with MET (folic acid, methionine, choline, vitamin B6, and vitamin B12). The results showed that maternal MET exposure during pregnancy significantly increased the concentrations of protein, triiodothyronine (T3), and thyroxine (T4) in colostrum and methyl metabolites, including S-adenosylmethionine (SAM), S-adenosyl-L-homocysteine (SAH), 5-methyl-tetrahydrofolate (5-MTHF), and betaine, in the maternal and offspring umbilical vein serum. A similar pattern was demonstrated in the body weight gain and myofiber diameters in offspring. In addition, maternal MET supplementation significantly increased the concentration of offspring serum insulin-like growth factor 1 (IGF-1), T3, and T4; upregulated the mRNA expression of IGF-1 and IGF-1 receptor (IGF-1r) and the phosphorylation level of protein kinases in offspring longissimus dorsi muscle; and upregulated the expression of myogenic genes and fast myosin heavy chain (fast MyHC) in offspring skeletal muscle. Supplementing sows with higher levels of MET during gestation may promote skeletal muscle differentiation and maturity and improve the skeletal muscle mass of the piglets.

Sex-biased transgenerational transmission of betaine-induced epigenetic modifications in glucocorticoid receptor gene and its down-stream BDNF/ERK pathway in rat hippocampus

Objectives: Glucocorticoid receptor (GR) expressed in hippocampus is critical for the homeostasis of stress responses and susceptible to epigenetic modulation caused by maternal factors. Here we show that maternal methyl nutrition causes sex-biased changes in hippocampal expression of GR exon 1 mRNA variants, associated with promoter DNA methylation, across two offspring generations in rats.Methods: Three-month-old female Sprague-Dawley rats (F0) were fed a diet supplemented with 1% betaine throughout the gestation and lactation. F0 dams and their F1 and F2 offspring of both sexes at weaning were used in the study.Results: A sex-specific transgenerational effect was observed. F2 females, but not males, followed the same pattern of their grand dams showing increased mRNA expression of total GR and its exons 1.4, 1.7, 1.10 and 1.11 variants coincided with promoter DNA hypomethylation in the hippocampus. However, F1 females, but not males, exhibited an opposite pattern, showing decreased expression of GR and its mRNA variants accompanied with promoter hypermethylation. The protein content of phospho-GR and BDNF/ERK in the hippocampus displayed the same sex and generation specificity.Discussion: These results indicate that maternal betaine exerts transgenerational effects on hippocampal GR expression and BDNF/ERK pathway in female rat offspring, with generation-dependent patterns of DNA methylation on alternative GR promoters.

The Effects of Maternal and Postnatal Dietary Methyl Nutrients on Epigenetic Changes that Lead to Non-Communicable Diseases in Adulthood

The risk for non-communicable diseases in adulthood can be programmed by early nutrition. This programming is mediated by changes in expression of key genes in various metabolic pathways during development, which persist into adulthood. These developmental modifications of genes are due to epigenetic alterations in DNA methylation patterns. Recent studies have demonstrated that DNA methylation can be affected by maternal or early postnatal diets. Because methyl groups for methylation reactions come from methionine cycle nutrients (i.e., methionine, choline, betaine, folate), deficiency or supplementation of these methyl nutrients can directly change epigenetic regulation of genes permanently. Although many studies have described the early programming of adult diseases by maternal and infant nutrition, this review discusses studies that have associated early dietary methyl nutrient manipulation with direct effects on epigenetic patterns that could lead to chronic diseases in adulthood. The maternal supply of methyl nutrients during gestation and lactation can alter epigenetics, but programming effects vary depending on the timing of dietary intervention, the type of methyl nutrient manipulated, and the tissue responsible for the phenotype. Moreover, the postnatal manipulation of methyl nutrients can program epigenetics, but more research is needed on whether this approach can rescue maternally programmed offspring.

Grandmaternal betaine supplementation enhances hepatic IGF2 expression in F2 rat offspring through modification of promoter DNA methylation

BACKGROUND

We reported previously that maternal betaine promotes hepatic insulin-like growth factor (IGF2) expression in F1 offspring rats through hypermethylation of the IGF2/H19 imprinting control region (ICR). It remains unknown whether this acquired trait can be transmitted to the F2 generation. This study aimed to determine whether dietary betaine supplementation to grand dams affects the hepatic IGF2 expression in F2 rat offspring and how it is related to alterations in DNA methylation. F2 rat offspring derived from grand dams fed basal or betaine-supplemented diet (10 g kg^-1 ) were examined at weaning. Serum IGF2 concentration was measured with enzyme-linked immunosorbent assay (ELISA). Hepatic expression of IGF2, together with other proliferation and apoptosis markers, was determined by using quantitative polymerase chain reaction (qPCR), western blot, and immunohistochemistry. The methylation status of the IGF2/H19 ICR and the promoters of IGF2 gene were detected by methylated DNA immunoprecipitation quantitative polymerase chain reaction (MeDIP-qPCR).

RESULTS

The maternal betaine-induced up-regulation of hepatic IGF2 expression in F1 rat offspring was transmitted to the F2 generation. The F2 rats from the betaine group demonstrated enhanced hepatic IGF2 expression at both mRNA and protein levels, in association with higher serum IGF2 concentration. No alterations were observed in the ICR methylation of the IGF2/H19 locus, and hypomethylation was detected in promoters of IGF2 gene in betaine group.

CONCLUSION

These results indicate that maternal betaine enhances hepatic IGF2 expression in F2 rat offspring through modification of DNA methylation on IGF2 promoters. © 2019 Society of Chemical Industry.

Using urine metabolomics to understand the pathogenesis of infant respiratory syncytial virus (RSV) infection and its role in childhood wheezing

BACKGROUND

Respiratory syncytial virus (RSV) infection in infants causes significant morbidity and is the strongest risk factor associated with asthma. Metabolites, which reflect the interactions between host cell and virus, provide an opportunity to identify the pathways that underlie severe infections and asthma development.

OBJECTIVE

To study metabolic profile differences between infants with RSV infection, and human rhinovirus (HRV) infection, and healthy infants. To compare infant metabolic differences between children who do and do not wheeze.

METHODS

In a term birth cohort, urine was collected while healthy and during acute viral respiratory infection with RSV and HRV. We used ¹H-NMR to identify urinary metabolites. Multivariate and univariate statistics were used to discriminate metabolic profiles of infants with either RSV ARI, or HRV ARI, and healthy infants. Multivariable logistic regression was used to assess the association of urine metabolites with 1st-, 2nd-, and 3rd-year recurrent wheezing.

RESULTS

Several metabolites in nicotinate and nicotinamide metabolism pathways were down-regulated in infants with RSV infection compared to healthy controls. There were no significant differences in metabolite profiles between infants with RSV infection and infants with HRV Infection. Alanine was strongly associated with reduced risk of 1st-year wheezing (OR 0.18[0.0, 0.46]) and 2nd-year wheezing (OR 0.31[0.13, 0.73]), while 2-hydroxyisobutyric acid was associated with increased 3rd-year wheezing (OR 5.02[1.49, 16.93]) only among the RSV infected subset.

CONCLUSION

The metabolites associated with infant RSV infection and recurrent-wheezing are indicative of viral takeover of the cellular machinery and resources to enhance virulence, replication, and subversion of the host immune-response, highlighting metabolic pathways important in the pathogenesis of RSV infection and wheeze development.

Methyl donors dietary supplementation to gestating sows diet improves the growth rate of offspring and is associating with changes in expression and DNA methylation of insulin-like growth factor-1 gene

The study aimed to investigate the effects of maternal dietary methyl donors on the performance of sows and their offspring, and the associated hepatic insulin-like growth factor-1 (IGF-1) expression of the offspring. A total of 24 multiparous sows were randomly fed the control (CON) or the CON diet supplemented with methyl donors (MD) at 3 g/kg betaine, 15 mg/kg folic acid, 400 mg/kg choline and 150 μg/kg VB₁₂ , from mating until delivery. After farrowing, sows were fed a common lactation diet through a 28-days lactation period and six litters per treatment were selected to be fed until at approximately 110 kg BW. Maternal MD supplementation resulted in greater birthweight (p < 0.05) and increased the piglet weights (p < 0.01) and litter weights (p < 0.05) at the age of day 28, compared with that in CON group. The offspring pigs in the MD group had greater ADG (p < 0.05) and tended to lower F:G ratio (p = 0.07) compared with that of CON group from day 28 to 180 of age. The offspring pigs from MD group had greater serum IGF-1 concentrations and expressions of hepatic IGF-1 gene and muscular IGF-1 receptor (IGF-1r) protein at birth (p < 0.05), and greater hepatic IGF-1 protein (p = 0.03) and muscular IGF-1r gene expressions (p < 0.05) at slaughter, than that from the CON group. Moreover, the methylation at the promoter of IGF-1 gene in the liver of newborn piglets and finishing pigs was greater in the MD group than that of the CON group (p < 0.05). In conclusion, maternal MD supplementation throughout gestation could enhance the birthweight and postnatal growth rate of offspring, associated with an increased expression of the IGF-1 gene and IGF-1r, as well as the altered DNA methylation of IGF-1 gene promotor.

Mitotically Stable Modification of DNA Methylation in IGF2/H19 Imprinting Control Region Is Associated with Activated Hepatic IGF2 Expression in Offspring Rats from Betaine-Supplemented Dams

The growth-promoting action of betaine involves activation of GH/IGF-1 signaling, yet it remains unclear whether insulin-like growth factor 2 (IGF2), an imprinting gene, is affected by maternal dietary betaine supplementation. In this study, F1 offspring rats derived from dams fed basal or betaine-supplemented diet were examined at D21 and D63. Maternal betaine significantly upregulated the hepatic expression of IGF2 mRNA and protein in offspring rats at both D21 and D63, which was accompanied by enhanced hepatic IGF2 immunoreactivity and elevated serum IGF-2 level. Higher protein expression of betaine-homocysteine methyltransferase and DNA methyltransferase 1 was detected in the betaine group at D21, but not D63. However, hypermethylation of the imprinting control region of the IGF2/H19 locus at D21 was maintained at D63. These results indicate that maternal betaine modifies DNA methylation of IGF2/H19 imprinting control region in a mitotically stable fasion, which was associated with the activation hepatic IGF2 expression in offspring rats.

Supplement of Betaine into Embryo Culture Medium Can Rescue Injury Effect of Ethanol on Mouse Embryo Development

Mammal embryos can be impaired by mother’s excessive ethanol uptake, which induces a higher level of reactive oxygen species (ROS) and interferes in one carbon unit metabolism. Here, our analysis by in vitro culture system reveals immediate effect of ethanol in medium on mouse embryo development presents concentration dependent. A preimplantation embryo culture using medium contained 1% ethanol could impact greatly early embryos development, and harmful effect of ethanol on preimplantation embryos would last during the whole development period including of reducing ratio of blastocyst formation and implantation, and deteriorating postimplantation development. Supplement of 50 μg/ml betaine into culture medium can effectively reduce the level of ROS caused by ethanol in embryo cells and rescue embryo development at each stage damaged by ethanol, but supplement of glycine can’t rescue embryo development as does betaine. Results of 5-methylcytosine immunodetection indicate that supplement of betaine into medium can reduce the rising global level of genome DNA methylation in blastocyst cells caused by 1% ethanol, but glycine can’t play the same impact. The current findings demonstrate that betaine can effectively rescue development of embryos harmed by ethanol, and possibly by restoring global level of genome DNA methylation in blastocysts.