The morphokinetic signature of human blastocysts with mosaicism and the clinical outcomes following transfer of embryos with low-level mosaicism.

BACKGROUND: Genetic mosaicism is commonly observed in human blastocysts. Embryos' morphokinetic feature observed from time-lapse monitoring (TLM) is helpful to predict the embryos' ploidy status in a non-invasive way. However, morphokinetic research on mosaic embryos is extremely limited. Moreover, transfer of mosaic embryos is a new attempt in reproductive medicine, while studies regarding the clinical and neonatal outcomes following transfer of embryos with different levels and types of mosaicism are needed. This study aimed to investigate the morphokinetic characteristics of mosaic blastocysts, uncover clinical outcomes of mosaic embryos, and evaluate the effect of level and type of mosaicism on transfer outcomes. RESULTS: A total of 923 blastocysts from 229 preimplantation genetic testing cycles were cultured in TLM incubators in a single fertilization center between July 2016 and July 2021. Multivariate logistic regression models showed mosaic embryos had significantly shorter time to reach morula when compared with euploid (P = 0.002), mosaic with aneuploid (P = 0.005), and aneuploid (P = 0.005) embryos after adjusting the potential confounders. KIDScore is an artificial intelligence scoring program from time lapse incubation system to predict embryo implantation potential. Mosaic with aneuploid embryos had significantly lower KIDScore than euploid (P = 6.47e-4), mosaic (P = 0.005), and aneuploid (P = 0.004) embryos after adjustment. Meanwhile, we compared the clinical outcomes following transfer of low-level (< 50%) mosaic embryos (N = 60) with euploid embryos (N = 1301) matched using propensity scoring collected from September 2020 to January 2023. Mosaic embryos had significantly lower clinical pregnancy rate (41.67% vs. 57.65%, P = 0.015) and live birth rate (38.33% vs. 51.35%, P = 0.048) than the euploid embryos. Subgroup analyses showed the whole, segmental, and complex chromosome mosaic embryos had the similar clinical outcomes. CONCLUSIONS: The shortened time to reach morula in mosaic embryos and the low KIDScore in mosaic with aneuploid embryos revealed innovative clues to embryo selection with the non-invasive TLM and provided new insights into biological mechanism of chromosomal abnormality. The analyses of overall and subgroups of mosaic embryo transfer outcomes helped to optimize embryo transfer scheme for in-vitro fertilization procedures. Multi-center prospective studies with large sample sizes are warranted to validate our results in the future.

Impacts of vitrification on the transcriptome of human ovarian tissue in patients with gynecological cancer.

Objective: This study investigated the effects of a vitrification/warming procedure on the mRNA transcriptome of human ovarian tissues. Design: Human ovarian tissues were collected and processed through vitrification (T-group) and then subjected to RNA sequencing (RNA-seq) analysis, HE, TdT-mediated dUTP nick-end labeling (TUNEL), and real-time quantitative PCR, and the results were compared to those of the fresh group (CK). Results: A total of 12 patients, aged 15-36 years old, with a mean anti-Müllerian hormone level of 4.57 ± 3.31 ng/mL were enrolled in this study. According to the HE and TUNEL results, vitrification effectively preserved human ovarian tissue. A total of 452 significantly dysregulated genes (|log2FoldChange| > 1 and p < 0.05) were identified between the CK and T groups. Among these, 329 were upregulated and 123 were downregulated. A total of 372 genes were highly enriched for 43 pathways (p < 0.05), which were mainly related to systemic lupus erythematous, cytokine-cytokine receptor interaction, the TNF signaling pathway, and the MAPK signaling pathway. IL10, AQP7, CCL2, FSTL3, and IRF7 were significantly upregulated (p < 0.01), while IL1RN, FCGBP, VEGFA, ACTA2, and ASPN were significantly downregulated in the T-group (p < 0.05) compared to the CK group, which agreed with the results of the RNA-seq analysis. Conclusion: These results showed (for the first time to the authors' knowledge) that vitrification can induce changes in mRNA expression in human ovarian tissues. Further molecular studies on human ovarian tissues are required to determine whether altered gene expression could result in any downstream consequences.

Recurrence for patients with first episode of hypertriglyceridemia-induced acute pancreatitis: A prospective cohort study.

BACKGROUND: Data on recurrent hypertriglyceridemia-induced acute pancreatitis (HTG-AP) are scarce. OBJECTIVE: To investigate the incidence and risk factors for recurrence of HTG-AP, and the effect of triglyceride (TG) lowering drugs post index attack on recurrence. METHODS: This study was a prospective cohort study of adult patients with first episode of HTG-AP from December 2019 to February 2021 who were followed until recurrence or death, or February 2022. The cumulative incidence function and Fine and Gray's competing-risk model were applied to the analyses. RESULTS: A total of 317 patients were enrolled, and the 12-month and 18-month cumulative recurrence incidences were 8% and 22%, respectively. The cumulative recurrence incidence was 2 times higher in patients whose serum TG levels post index attack were ≥5.65 mmol/L (subdistribution hazard ratio [SHR], 2.00; 95% confidence interval [CI], 1.05-3.80; P = 0.034) compared to patients with TG <5.65 mmol/L. The recurrence rate was 3.3 times higher in patients whose glucose levels post index attack were ≥7.0 mmol/L (SHR, 3.31; 95% CI, 1.56-7.03; P = 0.002) than in patients with glucose <7.0 mmol/L). Compared to TG lowering drugs for less than 1 month post index attack, treatment for longer than 12 months decreased the incidence of recurrence by 75% (SHR, 0.25; 95% CI, 0.08-0.80; P = 0.019). CONCLUSIONS: The HTG-AP recurrence incidence is high and closely associated with high levels of TGs and glucose post index attack. Long-term TG lowering drugs treatment significantly decreases this recurrence.

Can the combination of time-lapse parameters and clinical features predict embryonic ploidy status or implantation?

RESEARCH QUESTION: Can models based on artificial intelligence predict embryonic ploidy status or implantation potential of euploid transferred embryos? Can the addition of clinical features into time-lapse monitoring (TLM) parameters as input data improve their predictive performance? DESIGN: A single academic fertility centre, retrospective cohort study. A total of 773 high-grade euploid and aneuploid blastocysts from 212 patients undergoing preimplantation genetic testing (PGT) between July 2016 and July 2021 were studied for ploidy prediction. Among them, 170 euploid embryos were single-transferred and included for implantation analysis. Five machine learning models and two types of deep learning networks were used to develop the predictive algorithms. The predictive performance was measured using the area under the receiver operating characteristic curve (AUC), in addition to accuracy, precision, recall and F1 score. RESULTS: The most predictive model for ploidy prediction had an AUC, accuracy, precision, recall and F1 score of 0.70, 0.64, 0.64, 0.50 and 0.56, respectively. The DNN-LSTM model showed the best predictive performance with an AUC of 0.78, accuracy of 0.77, precision of 0.79, recall of 0.86 and F1 score of 0.83. The predictive power was improved after the addition of clinical features for the algorithms in ploidy prediction and implantation prediction. CONCLUSION: Our findings emphasize that clinical features can largely improve embryo prediction performance, and their combination with TLM parameters is robust to predict high-grade euploid blastocysts. The models for ploidy prediction, however, were not highly predictive, suggesting they cannot replace preimplantation genetic testing currently.

IRX3 Promotes the Browning of White Adipocytes and Its Rare Variants are Associated with Human Obesity Risk.

BACKGROUND: IRX3 was recently reported as the effector of the FTO variants. We aimed to test IRX3's roles in the browning program and to evaluate the association between the genetic variants in IRX3 and human obesity. METHODS: IRX3 expression was examined in beige adipocytes in human and mouse models, and further validated in induced beige adipocytes. The browning capacity of primary preadipocytes was assessed with IRX3 knockdown. Luciferase reporter analysis and ChIP assay were applied to investigate IRX3's effects on UCP1 transcriptional activity. Moreover, genetic analysis of IRX3 was performed in 861 young obese subjects and 916 controls. RESULTS: IRX3 expression was induced in the browning process and was positively correlated with the browning markers. IRX3 knockdown remarkably inhibited UCP1 expression in induced mouse and human beige adipocytes, and also repressed the uncoupled oxygen consumption rate. Further, IRX3 directly bound to UCP1 promoter and increased its transcriptional activity. Moreover, 17 rare heterozygous missense/frameshift IRX3 variants were identified, with a significant enrichment in obese subjects (P=0.038, OR=2.27; 95% CI, 1.02-5.05). CONCLUSIONS: IRX3 deficiency repressed the browning program of white adipocytes partially by regulating UCP1 transcriptional activity. Rare variants of IRX3 were associated with human obesity.

Genetic interaction of DGAT2 and FAAH in the development of human obesity.

PURPOSE: DGAT2 is the critical catalyzing enzyme for triglyceride biosynthesis, and excess triglyceride accumulation in fat tissues is a fundamental process for obesity. Mutations in DGAT2 or other genes interacting with DGAT2 associated with adiposity have not been reported in human to date. METHODS: DGAT2 mutation was identified based on our in-home database-exome sequencing 227 young obese subjects (body-mass index (BMI), 35.1-61.7 kg/m2) and 219 lean controls (BMI, 17.5-23.0 kg/m2), further validated in 1190 lean subjects and the pedigree of the proband. The trios of the proband were further subjected to whole-exome sequencing to explore the candidate genes for obesity. The mutations in DGAT2 and FAAH were functionally evaluated in vitro. RESULTS: We detected two rare variants in DGAT2 with no significant difference between obese and lean individuals. One novel heterozygous nonsense variant c.382C > T (p.R128*) was identified in one obese subject but not in 219 lean subjects and another 1190 lean subjects. Notably, in vitro study showed that R128* mutation severely damaged the TG-biosynthesis ability of DGAT2, and all other R128* carriers in the pedigree were lean. Thus, we further identified a loss-of-function variant c. 944G > T (p.R315I) in FAAH in the proband inheriting from his obese father. Importantly, FAAH overexpression inhibited DGAT2 expression and TG synthesis, while R315I mutant largely eliminated this inhibitory effect. We first report loss-of-function mutations in DGAT2 and FAAH in one obese subject, which may interact with each other to affect the adiposity penetrance, providing a model of genetic interaction associated with human obesity.

Rare Loss-of-Function Variants in NPC1 Predispose to Human Obesity.

Some Shanghai Clinical Center f a role of Niemann-Pick type C1 (NPC1) for obesity traits. However, whether the loss-of-function mutations in NPC1 cause adiposity in humans remains unknown. We recruited 25 probands with rare autosomal-recessive Niemann-Pick type C (NP-C) disease and their parents in assessment of the effect of heterozygous NPC1 mutations on adiposity. We found that male NPC1+/- carriers had a significantly higher BMI than matched control subjects or the whole population-based control subjects. Consistently, male NPC1+/- mice had increased fat storage while eating a high-fat diet. We further conducted an in-depth assessment of rare variants in the NPC1 gene in young, severely obese subjects and lean control subjects and identified 17 rare nonsynonymous/frameshift variants in NPC1 (minor allele frequency <1%) that were significantly associated with an increased risk of obesity (3.40% vs. 0.73%, respectively, in obese patients and control subjects, P = 0.0008, odds ratio = 4.8, 95% CI 1.7-13.2), indicating that rare NPC1 variants were enriched in young, morbidly obese Chinese subjects. Importantly, participants carrying rare variants with severely damaged cholesterol-transporting ability had more fat accumulation than those with mild/no damage rare variants. In summary, rare loss-of-function NPC1 mutations were identified as being associated with human adiposity with a high penetrance, providing potential therapeutic interventions for obesity in addition to the role of NPC1 in the familial NP-C disease.

Association of a gain-of-function variant in LGR4 with central obesity.

OBJECTIVE: To determine the relationship of the gain-of-function variant A750T in leucine-rich repeat containing G protein-coupled receptor 4 (LGR4) with central obesity and related metabolic phenotypes. METHODS: The LGR4 A750T (c.2248 G > A) variant was detected by Sanger sequencing in a discovery young population and a validation community-based population with obesity from eastern China. Fat indices determined by anthropometry and computed tomography scans and clinical biochemical measurements were collected for association analysis. RESULTS: LGR4 A750T was significantly correlated with waist circumference (P = 0.030) and waist-to-height ratio (P < 0.001) in the young cohort (N = 594) and with waist-to-hip ratio (P = 0.013) in the community population (N = 1067). Combined analysis showed a significant correlation of the variant with waist circumference (P < 0.001) and waist-to-hip ratio (P = 0.021). Moreover, the variant had a remarkable correlation with abdominal visceral fat area (P = 0.004) and was associated with 2-h plasma insulin (P = 0.009) and the Matsuda index (P = 0.027) after an oral glucose tolerance test in young subjects with obesity. CONCLUSIONS: The LGR4 A750T variant may contribute to central obesity characterized by abdominal visceral fat accumulation.

Ablation of Lgr4 enhances energy adaptation in skeletal muscle via activation of Ampk/Sirt1/Pgc1α pathway.

Leucine-rich repeat-containing G protein-coupled receptor 4 (Lgr4) is a newfound obese-associated gene. Previous study reveals that heterozygous mutation of Lgr4 correlates with decreased body weight in human. In our recent study, we demonstrate that Lgr4 ablation promotes browning of white adipose tissue and improves whole-body metabolic status. However little is known about its role in other metabolic tissues. Herein, we show that Lgr4 homozygous mutant (Lgr4(m/m)) mice show increased respiratory exchange ratio (RER, closer to 1.0) than wild-type mice at 12:00 AM (food-intake time for mice) while decreased RER (closer to 0.75) at 12:00 PM (fasting for mice), indicating a glucose-prone versus fatty acid-prone metabolic pattern, respectively. Furthermore, Lgr4 ablation increases lipid oxidation-related gene expression while suppresses glucose transporter type 4 (Glut4) levels in skeletal muscle under fasting condition. These data suggest that Lgr4 ablation enhances the flexibility of skeletal muscle to switch energy provider from glucose to fatty acid in response to glucose depletion. We further reveal the activation of Ampk/Sirt1/Pgc1α pathway during this adaptive fuel shift due to Lgr4 ablation. This study suggests that Lgr4 might serve as an adaptive regulator between glucose and lipid metabolism in skeletal muscle and reveals a potentially new regulator for a well-established adaptive network.