Project description:Neural tube defects (NTDs) are serious congenital malformations. Excessive maternal homocysteine (Hcy) increases the risk of NTDs, while its mechanism remains elusive. In this study, we evaluated the role of histone homocysteinylation in neural tube closure (NTC). A total of 39 histone homocysteinylation sites were identified in samples from human embryonic brain tissue using mass spectrometry. Elevated levels of histone KHcy and H3K79Hcy were detected at increased cellular Hcy levels in human fetal brains. Using ChIP-seq and RNA-seq assays, we demonstrated that increase in H3K79Hcy level downregulated the expression of selected NTC-related genes including Cecr2, Smarca4, and Dnmt3b. In human NTD brain tissues, decrease in expression of Cecr2, Smarca4, and Dnmt3b was also detected along with high levels of Hcy and H3K79Hcy. Our results suggest that higher levels of Hcy contribute to the onset of NTDs through upregulation of histone H3K79Hcy, leading to abnormal expression of selected NTC-related genes.
Project description:Neural tube defects (NTDs) are serious congenital malformations. Excessive maternal homocysteine (Hcy) increases the risk of NTDs, while its mechanism remains elusive. In this study, we evaluated the role of histone homocysteinylation in neural tube closure (NTC). A total of 39 histone homocysteinylation sites were identified in samples from human embryonic brain tissue using mass spectrometry. Elevated levels of histone KHcy and H3K79Hcy were detected at increased cellular Hcy levels in human fetal brains. Using ChIP-seq and RNA-seq assays, we demonstrated that increase in H3K79Hcy level downregulated the expression of selected NTC-related genes including Cecr2, Smarca4, and Dnmt3b. In human NTD brain tissues, decrease in expression of Cecr2, Smarca4, and Dnmt3b was also detected along with high levels of Hcy and H3K79Hcy. Our results suggest that higher levels of Hcy contribute to the onset of NTDs through upregulation of histone H3K79Hcy, leading to abnormal expression of selected NTC-related genes.
Project description:Background: Neural tube defects (NTDs) are congenital malformations that occur when the neural tube fails to close properly during early embryonic development. However, the identity of affected celltypes and pathogenic mechanisms remain unclear due to the lack of clinical samples. Method: We utilized single-nucleus RNA sequencing to analyze 37,064 neural tube cells from NTDs and normal abortus at 14 and 15 gestational weeks. Multiplexed immunofluorescence staining was performed to further validate some phenotypes. Results: Firstly, we revealed that the most affected celltypes are excitatory neurons, inhibitory neurons, and astrocytes. We further elucidated that the main subtypes mediating abnormal development in NTDs is IGF2high subtypes in inhibitory neurons and MEG3high subtypes in astrocytes. Importantly, our findings highlighted IGF2 as a pivotal gene for abnormal development and abnormal cell-cell communications in NTDs. Conclusions: In summary, this study presents the first single-cell atlas of NTDs and provides new insights for further research into the underlying mechanisms of NTDs.
Project description:Neural tube defects (NTDs) are one of the most severe congenital abnormalities. Maternal folate deficiency could impact the occurrence of NTDs. Histone H3 methyltransferase disruptor of telomeric silencing 1-like (DOT1L) expression was significantly downregulated, and low levels of H3K79me2 were found in the corresponding NTDs samples with their maternal serum folate under low levels. Using ChIP-seq assays, we found that a decrease of H3K79me2 downregulates the expression of Shh and Sufu in mouse embryonic stem cells (mESC) under folate deficiency. Our results indicate that abnormal Shh and Sufu genes expression reduced by aberrant Dot1l-mediated H3K79me2 levels could be the cause of NTDs occurrence.
Project description:To investigate the associated with abnormal DNA demethylation and neural tube defects (NTDs) with folate deficiency, we etablished mouse embryonic stem cells (mESCs) Sv/129 in folate-deficiency-treated.
Project description:To investigate the associated with abnormal DNA demethylation and neural tube defects (NTDs) with folate deficiency, we etablished mouse embryonic stem cells (mESCs) Sv/129 in folate-deficiency-treated.
Project description:To investigate the associated with DNA demethylation and neural tube defects (NTDs) with folate deficiency, we etablished mouse embryonic stem cells (mESCs) Sv/129 in folate-deficiency-treated.
Project description:<p>Maternal folic acid intake is crucial for the development of the offspring's nervous system, and folic acid metabolism disorders during pregnancy lead to neural tube defects (NTDs) in the fetus. Folic acid and vitamins biosynthesis is a major biochemical feature of gut microbiota. The complex and diverse microbial ecosystem residing within maternal host contributes critically to these intergenerational impacts. However, the mechanisms still require further investigation. In this study, we found that the low folate diets combined MTX-induced changed the structure/composition of the gut microbiota and substantially altered the fecal metabolic phenotype of pregnant mice, including central carbon metabolism in cancer and vitamin digestion & absorption. We demonstrated that the correlation betweent gut microbiota of pregnant mice and the brain metabolic profiles of NTDs fetal mice. According to our data, the Lactobacillales and Bifidobacteriales abundances in pregnant mice gut were positively correlated with the abundances of lipid metabolites in fetal mice brain. The abundances of Enterobacterales and Clostridiales were negatively correlated with those lipid metabolites. Interestingly, the abundance of Inosine, Uridine, L-Carnitine and Glycerophosphocholine were down-regulated synchronously in pregnant feces and NTDs fetal mice brain. This was probably the intergenerational microbial-metabolism biomarkers of NTDs. Our study provides evidence for how perinatal microecological factors shape fetal neural tube development.</p><p><br></p><p><strong>Feces metabolomics</strong> is reported in the current study <a href='https://www.ebi.ac.uk/metabolights/MTBLS4893' rel='noopener noreferrer' target='_blank'><strong>MTBLS4893</strong></a>.</p><p><strong>Brain tissue metabolomics</strong> is reported in <a href='https://www.ebi.ac.uk/metabolights/MTBLS4894' rel='noopener noreferrer' target='_blank'><strong>MTBLS4894</strong></a>.</p>