A Biallelic Frameshift Mutation in Nephronectin Causes Bilateral Renal Agenesis in Humans.

BACKGROUND: Bilateral renal agenesis (BRA) is a lethal con genital anomaly caused by the failure of normal development of both kidneys early in embryonic development. Oligohydramnios on fetal ultrasonography reveals BRA. Although the exact causes are not clear, BRA is associated with mutations in many renal development genes. However, molecular diagnostics do not pick up many clinical patients. Nephronectin (NPNT) may be a candidate protein for widening diagnosis. It is essential in kidney development, and knockout of Npnt in mice frequently leads to kidney agenesis or hypoplasia. METHODS: A consanguineous Han family experienced three cases of induced abortion in the second trimester of pregnancy, due to suspected BRA. Whole-exome sequencing (WES)-based homozygosity mapping detected underlying genetic factors, and a knock-in mouse model confirmed the renal agenesis phenotype. RESULTS: WES and evaluation of homozygous regions in II:3 and II:4 revealed a pathologic homozygous frameshift variant in NPNT (NM_001184690:exon8:c.777dup/p.Lys260*), which leads to a premature stop in the next codon. The truncated NPNT protein exhibited decreased expression, as confirmed in vivo by the overexpression of WT and mutated NPNT. A knock-in mouse model homozygous for the detected Npnt mutation replicated the BRA phenotype. CONCLUSIONS: A biallelic loss-of-function NPNT mutation causing an autosomal recessive form of BRA in humans was confirmed by the corresponding phenotype of knock-in mice. Our results identify a novel genetic cause of BRA, revealing a new target for genetic diagnosis, prenatal diagnosis, and preimplantation diagnosis for families with BRA.

Epigenetic insights into Fragile X Syndrome.

Fragile X Syndrome (FXS) is a genetic neurodevelopmental disorder closely associated with intellectual disability and autism spectrum disorders. The core of the disease lies in the abnormal expansion of the CGG trinucleotide repeat sequence at the 5'end of the FMR1 gene. When the repetition exceeds 200 times, it causes the silencing of the FMR1 gene, leading to the absence of the encoded Fragile X mental retardation protein 1 (FMRP). Although the detailed mechanism by which the CGG repeat expansion triggers gene silencing is yet to be fully elucidated, it is known that this process does not alter the promoter region or the coding sequence of the FMR1 gene. This discovery provides a scientific basis for the potential reversal of FMR1 gene silencing through interventional approaches, thereby improving the symptoms of FXS. Epigenetics, a mechanism of genetic regulation that does not depend on changes in the DNA sequence, has become a new focus in FXS research by modulating gene expression in a reversible manner. The latest progress in molecular genetics has revealed that epigenetics plays a key role in the pathogenesis and pathophysiological processes of FXS. This article compiles the existing research findings on the role of epigenetics in Fragile X Syndrome (FXS) with the aim of deepening the understanding of the pathogenesis of FXS to identify potential targets for new therapeutic strategies.

Phosphoglycerate mutase 5 promotes necroptosis in trophoblast cells through activation of dynamin-related protein 1 in early-onset preeclampsia.

OBJECTIVES: Placentae from patients with preeclampsia have increased susceptibility to necroptosis and phosphoglycerate mutase 5 (PGAM5) plays a role in many necrosis pathways. We determined whether PGAM5 promotes necroptosis of trophoblast cells and the underlying mechanisms in this study. METHODS: The injury model was established by treating JEG3 cells with hypoxia for 24 h. The functional measurements were assessed by the cell counting kit-8, propidium iodide (PI)/Annexin V staining, JC-1 staining and firefly luciferase ATP assay. The expression of proteins in human placentae and JEG3 cells was measured Western blot. PGAM5 was knocked down to study its role in hypoxia-induced necroptosis. RESULTS: The placentae from patients with preeclampsia showed up-regulation of PGAM5 and decreased levels of p-Drp1-S637, accompanied by increased necroptosis-relevant proteins expression. The expression of PGAM5 in JEG3 cells was up-regulated under hypoxia, which promoted dephosphorylation of Drp1 at Serine 637 residue, mitochondrial dysfunction (elevated ROS level and reduced mitochondrial membrane potential and ATP content) and cellular necroptosis (increased PI+ /Annexin V+ cells and decreased cell viability), accompanied by increased expression of necroptosis-relevant proteins; knockdown of PGAM5 attenuated these phenomena. CONCLUSIONS: Our results indicate that PGAM5 can promote necroptosis in trophoblast cells through, at least in part, activation of Drp1. It may be used as a new therapeutic target to prevent trophoblast dysfunction in preeclampsia.

Loss-of-Function Plays a Major Role in Early Neurogenesis of Tubulin α-1 A (TUBA1A) Mutation-Related Brain Malformations.

Tubulin α-1 A (TUBA1A) mutations cause a wide spectrum of brain abnormalities. Although many mutations have been identified and functionally verified, there are clearly many more, and the relationship between TUBA1A mutations and brain malformations remains unclear. The aim of this study was to identify a TUBA1A mutation in a fetus with severe brain abnormalities, verify it functionally, and determine the mechanism of the mutation-related pathogenesis. A de novo missense mutation of the TUBA1A gene, c.167C>G p.T56R/P.THR56Arg, was identified by exon sequencing. Computer simulations showed that the mutation results in a disruption of lateral interactions between the microtubules. Transfection of 293T cells with TUBA1A p.T56R showed that the mutated protein is only partially incorporated into the microtubule network, resulting in a decrease in the rate of microtubule re-integration in comparison with the wild-type protein. The mechanism of pathological changes induced by the mutant gene was determined by knockdown and overexpression. It was found that knockdown of TUBA1A reduced the generation of neural progenitor cells, while overexpression of wild-type or mutant TUBA1A promoted neurogenesis. Our identification and functional verification of the novel TUBA1A mutation extends the TUBA1A gene-phenotype database. Loss-of-function of TUBA1A was shown to play an important role in early neurogenesis of TUBA1A mutation-related brain malformations.

Hypertensive disorders of pregnancy and risks of adverse pregnancy outcomes: a retrospective cohort study of 2368 patients.

Hypertensive disorders of pregnancy (HDP) comprise a group of hypertension-related diseases and represent the most common medical disorders in pregnancy. The aim of this study was to investigate the risks of adverse pregnancy outcomes in patients with different types of HDP, including gestational hypertension, chronic hypertension, preeclampsia (PE, early or late onset), PE superimposed on chronic hypertension (superimposed PE), eclampsia, and HELLP syndrome. Data from a multicenter retrospective patient cohort in China were analyzed. Seventeen adverse maternal or perinatal outcomes were evaluated. Logistic regression was used to estimate the risk of adverse outcomes for each HDP subgroups, using the gestational hypertension group as the reference. The final analysis included 2368 patients with HDP. Of these, 39.9% of patients reported at least one adverse pregnancy outcome. Patients with early onset PE had the highest risk for having both adverse maternal and perinatal outcomes (OR = 7.28, 95% CI: 2.68, 19.79). The risk of perinatal death significantly increased in HELLP syndrome, superimposed PE, and early onset PE, (OR = 13.81, 6.32, and 4.84, respectively, p < 0.05) groups. This study highlights that among patients with HDP, those with early onset PE had the highest risk for having both adverse maternal and perinatal outcomes, and patients with HELLP syndrome had the highest risk for perinatal death.

Single-cell RNA sequencing reveals heterogeneity and differential expression of decidual tissues during the peripartum period.

OBJECTIVES: The decidua is a tissue that contacts both maternal and foetal components and is pivotal to labour onset due to its location. Due to the heterogeneity of decidual tissue, it is challenging to study its role in the peripartum period. Herein, we analysed the transcriptomes of peripartum decidua at single-cell resolution. MATERIALS AND METHODS: Single-cell RNA sequencing was performed for 29 231 decidual cells before and after delivery to characterize the transcriptomes. RESULTS: Eight major cell types (including endothelial cells, fibroblasts) and subtypes of decidual stromal cells, extravillous trophoblasts and T cells were identified and found to have various functions. Compared with before delivery, the activation of decidual stromal cell, extravillous trophoblast and T-cell subtypes to different degrees was observed after delivery. Furthermore, the activation involved multiple functions, such as cell proliferation, and several pathways, such as the activator protein 1 pathway. The results of pseudotemporal ordering showed differentiation of decidual stromal cell and extravillous trophoblast subtypes, suggesting inhomogeneity of these subgroups in decidualization (decidual stromal cell) and invasion (extravillous trophoblast). CONCLUSIONS: The peripartum decidual tissue is heterogeneous. This study revealed changes in the decidua and its components at single-cell resolution; these findings provide a new perspective for the study of peripartum decidua.

Cell growth inhibition and gene expression regulation by (-)-epigallocatechin-3-gallate in human cervical cancer cells.

EGCG [(-)-epigallocatechin-3-gallate] has shown its antitumor ability and perhaps a potential regimen for cancer patients. The goal of this study was to investigate the effect of EGCG on human papilloma virus (HPV) positive cervical cancer cell lines. EGCG inhibited the growth of CaSki (HPV16 positive) and HeLa (HPV18 positive) cells in a time- and concentration-dependent manner. Cell cycle arrest and apoptosis were observed in two cell lines after EGCG exposure. More importantly, we focused on EGCG regulation ability on pivotal genes involved in cervical cancer: viral oncogenes E6/E7, estrogen receptor (ER) and aromatase. Our results suggested that EGCG may be suitable for prevention and treatment of cervical cancer.

Generation of a homozygous HDAC6 knockout human embryonic stem cell line by CRISPR/Cas9 editing.

Histone deacetylase 6 (HDAC6) is a unique cytoplasmic enzyme in the HDAC family. The HDAC6 has been shown to play important roles in several biological processes. Meanwhile, it is also an attractive therapeutic target for a variety of diseases. However, the mechanism of HDAC6 function is not fully understood yet, and it is still lacking highly specific targeted drugs. Here, we generated a homozygous HDAC6 knockout human embryonic stem cell (hESC) line, WAe009-A-21 by the CRISPR/Cas9-based gene editing method. The WAe009-A-21 cell line does not express HDAC6 protein, while maintaining normal 46, XX karyotype, pluripotency, and trilineage differentiation potential.

Risk factors for adverse maternal and perinatal outcomes in women with preeclampsia: analysis of 1396 cases.

Preeclampsia is a major cause of adverse maternal and perinatal outcomes, but how to identify women and fetuses at increased risk for later adverse events is a challenge. This study aimed to investigate the risk factors for adverse maternal and perinatal outcomes in women with preeclampsia. Data from 1396 women with preeclampsia were retrospectively collected and analyzed. Eighteen candidate risk factors and 12 adverse outcomes were investigated. The following factors were found to be significantly associated with at least one adverse outcome: maternal age 35 years or older, multiple birth, the usage of assisted reproductive technology, living in a rural area, history of pregnancy-induced hypertension, male fetus, multigravida, or having polycystic ovary syndrome, hemolysis, elevated liver enzymes, and low platelet count syndrome, intrahepatic cholestasis of pregnancy, cardiovascular disease, gestational diabetes mellitus, systemic lupus erythematosus, thyroid disease, or liver disease. Compared with patients without any identified risk factors, patients with preeclampsia with three or more risk factors were at increased risk for severe adverse outcomes. Those findings demonstrated that maternal risk factors could be used as indicators supplementary to clinical symptoms and laboratory test results for the risk assessment in women with preeclampsia.

Preterm birth, low birthweight, and small for gestational age among women with preeclampsia: Does maternal age matter?

OBJECTIVES: To better understand the effects of maternal age on birth outcomes among preeclampsia (PE) patients, we examined the rates of preterm birth, low birthweight, and small for gestational age (SGA) among different age groups and explored whether maternal age was associated with those adverse outcomes. STUDY DESIGN: This is a multicenter retrospective study. Data from 1128 PE patients, including 580 with early onset PE and 548 with late onset PE, were analyzed. MAIN OUTCOME MEASURES: Maternal age was categorized into three groups: <25, 25-34, and ≥35 years. The outcome variables were preterm birth (<37 weeks; subgroups: <28 weeks, 28-33 weeks, and 34-36 weeks), low birthweight (<2500 g; subgroups: <1500 g and <1000 g), and SGA. Logistic regression was used to analyze the associations between maternal age groups and outcomes. RESULTS: In early onset PE, compared with maternal age 25-34 years, maternal age ≥35 years was associated with elevated risk for preterm delivery before 28 weeks, and maternal age <25 years was associated with elevated risk for low birthweight and SGA. When the analysis was restricted to women who underwent cesarean section, elevated risks for preterm birth and/or low birthweight were observed for women younger than 25 years in both early and late onset PE. CONCLUSIONS: Among women with PE, maternal age <25 years could add risk to preterm birth and/or low birthweight. For women with early onset PE, maternal age ≥35 years is a risk factor for preterm delivery before 28 weeks.