3D reconstruction of a gastrulating human embryo.

Progress in understanding early human development has been impeded by the scarcity of reference datasets from natural embryos, particularly those with spatial information during crucial stages like gastrulation. We conducted high-resolution spatial transcriptomics profiling on 38,562 spots from 62 transverse sections of an intact Carnegie stage (CS) 8 human embryo. From this spatial transcriptomic dataset, we constructed a 3D model of the CS8 embryo, in which a range of cell subtypes are identified, based on gene expression patterns and positional register, along the anterior-posterior, medial-lateral, and dorsal-ventral axis in the embryo. We further characterized the lineage trajectories of embryonic and extra-embryonic tissues and associated regulons and the regionalization of signaling centers and signaling activities that underpin lineage progression and tissue patterning during gastrulation. Collectively, the findings of this study provide insights into gastrulation and post-gastrulation development of the human embryo.

A mobile robotic chemist.

Technologies such as batteries, biomaterials and heterogeneous catalysts have functions that are defined by mixtures of molecular and mesoscale components. As yet, this multi-length-scale complexity cannot be fully captured by atomistic simulations, and the design of such materials from first principles is still rare1-5. Likewise, experimental complexity scales exponentially with the number of variables, restricting most searches to narrow areas of materials space. Robots can assist in experimental searches6-14 but their widespread adoption in materials research is challenging because of the diversity of sample types, operations, instruments and measurements required. Here we use a mobile robot to search for improved photocatalysts for hydrogen production from water15. The robot operated autonomously over eight days, performing 688 experiments within a ten-variable experimental space, driven by a batched Bayesian search algorithm16-18. This autonomous search identified photocatalyst mixtures that were six times more active than the initial formulations, selecting beneficial components and deselecting negative ones. Our strategy uses a dexterous19,20 free-roaming robot21-24, automating the researcher rather than the instruments. This modular approach could be deployed in conventional laboratories for a range of research problems beyond photocatalysis.

Ribosomal frameshifting at normal codon repeats recodes functional chimeric proteins in human.

Ribosomal frameshifting refers to the process that ribosomes slip into +1 or -1 reading frame, thus produce chimeric trans-frame proteins. In viruses and bacteria, programmed ribosomal frameshifting can produce essential trans-frame proteins for viral replication or regulation of other biological processes. In humans, however, functional trans-frame protein derived from ribosomal frameshifting is scarcely documented. Combining multiple assays, we show that short codon repeats could act as cis-acting elements that stimulate ribosomal frameshifting in humans, abbreviated as CRFS hereafter. Using proteomic analyses, we identified many putative CRFS events from 32 normal human tissues supported by trans-frame peptides positioned at codon repeats. Finally, we show a CRFS-derived trans-frame protein (HDAC1-FS) functions by antagonizing the activities of HDAC1, thus affecting cell migration and apoptosis. These data suggest a novel type of translational recoding associated with codon repeats, which may expand the coding capacity of mRNA and diversify the regulation in human.

Post-translational modification localizes MYC to the nuclear pore basket to regulate a subset of target genes involved in cellular responses to environmental signals.

The transcription factor MYC (also c-Myc) induces histone modification, chromatin remodeling, and the release of paused RNA polymerase to broadly regulate transcription. MYC is subject to a series of post-translational modifications that affect its stability and oncogenic activity, but how these control MYC's function on the genome is largely unknown. Recent work demonstrates an intimate connection between nuclear compartmentalization and gene regulation. Here, we report that Ser62 phosphorylation and PIN1-mediated isomerization of MYC dynamically regulate the spatial distribution of MYC in the nucleus, promoting its association with the inner basket of the nuclear pore in response to proliferative signals, where it recruits the histone acetyltransferase GCN5 to bind and regulate local gene acetylation and expression. We demonstrate that PIN1-mediated localization of MYC to the nuclear pore regulates MYC target genes responsive to mitogen stimulation that are involved in proliferation and migration pathways. These changes are also present at the chromatin level, with an increase in open regulatory elements in response to stimulation that is PIN1-dependent and associated with MYC chromatin binding. Taken together, our study indicates that post-translational modification of MYC controls its spatial activity to optimally regulate gene expression in response to extrinsic signals in normal and diseased states.

Candesartan upregulates angiotensin-converting enzyme 2 in kidneys of male animals by decreased ubiquitination.

Candesartan is a common angiotensin-II receptor-1 blocker used for patients with cardiovascular and renal diseases. Angiotensin-converting enzyme 2 (ACE2) is a negative regulator of blood pressure (BP), and also a major receptor for coronaviruses. To determine whether and how candesartan upregulates ACE2, we examined BP and ACE2 in multi-organs from male and female C57BL/6J mice treated with candesartan (1 mg/kg, i.p.) for 7 days. Relative to the vehicle, candesartan lowered BP more in males than females; ACE2 protein abundances were increased in kidneys, not lungs, hearts, aorta, liver, spleen, brain, or serum, only from males. Ace2-mRNA was similar in kidneys. Candesartan also decreased BP in normal, hypertensive, and nephrotic male rats. The renal ACE2 was increased by the drug in normal and nephrotic male rats but not spontaneously hypertensive ones. In male mouse kidneys, ACE2 was distributed at sodium-hydrogen-exchanger-3 positive proximal-convoluted-tubules; ACE2-ubiquitination was decreased by candesartan, accompanied with increased ubiquitin-specific-protease-48 (USP48). In candesartan-treated mouse renal proximal-convoluted-tubule cells, ACE2 abundances and activities were increased while ACE2-ubiquitination and colocalization with lysosomal and proteosomal markers were decreased. The silence of USP48 by siRNA caused a reduction of ACE2 in the cells. Thus, the sex-differential ACE2 upregulation by candesartan in kidney from males may be due to the decreased ACE2-ubiquitination, associated with USP48, and consequent degradation in lysosomes and proteosomes. This is a novel mechanism and may shed light on candesartan-like-drug choice in men and women prone to coronavirus infections.

Passer, a highly active transposon from a fish genome, as a potential new robust genetic manipulation tool.

The discovery of new, active DNA transposons can expand the range of genetic tools and provide more options for genomic manipulation. In this study, a bioinformatics analysis suggested that Passer (PS) transposons, which are members of the pogo superfamily, show signs of recent and current activity in animals and may be active in some species. Cell-based transposition assays revealed that the native PS transposases from Gasterosteus aculeatus and Danio rerio displayed very high activity in human cells relative to the Sleeping Beauty transposon. A typical overproduction inhibition phenomenon was observed for PS, and transposition capacity was decreased by ∼12% with each kilobase increase in the insertion size. Furthermore, PS exhibited a pronounced integration preference for genes and their transcriptional regulatory regions. We further show that two domesticated human proteins derived from PS transposases have lost their transposition activity. Overall, PS may represent an alternative with a potentially efficient genetic manipulation tool for transgenesis and mutagenesis applications.

Kirigami-based metastructures with programmable multistability.

SignificanceDifferent from most existing multistable structures whose multiple stable states are achieved through the combinational effect of bistable units, we invent a generic tristable kirigami cuboid. The three stable states have fundamentally distinct geometric configurations and chirality, and the transformation among them can be realized by tension/compression or clockwise/counterclockwise twist. Tessellating the units in series, a family of multistable metamaterials can be constructed, the mechanical behaviors of which are programmable by the unit geometry, the material of the elastic joints, the number of units, and the loading conditions. As a demonstration of the potential applications, a frequency reconfigurable antenna for 5G triple-band communication is developed based on a tristable unit, and the frequency tunability is verified by experiments.

Uridylation and the SKI complex orchestrate the Calvin cycle of photosynthesis through RNA surveillance of TKL1 in Arabidopsis.

RNA uridylation, catalyzed by terminal uridylyl transferases (TUTases), represents a conserved and widespread posttranscriptional RNA modification in eukaryotes that affects RNA metabolism. In plants, several TUTases, including HEN1 SUPPRESSOR 1 (HESO1) and UTP: RNA URIDYLYLTRANSFERASE (URT1), have been characterized through genetic and biochemical approaches. However, little is known about their physiological significance during plant development. Here, we show that HESO1 and URT1 act cooperatively with the cytoplasmic 3'-5' exoribonucleolytic machinery component SUPERKILLER 2 (SKI2) to regulate photosynthesis through RNA surveillance of the Calvin cycle gene TRANSKETOLASE 1 (TKL1) in Arabidopsis. Simultaneous dysfunction of HESO1, URT1, and SKI2 resulted in leaf etiolation and reduced photosynthetic efficiency. In addition, we detected massive illegitimate short interfering RNAs (siRNAs) from the TKL1 locus in heso1 urt1 ski2, accompanied by reduced TKL1/2 expression and attenuated TKL activities. Consequently, the metabolic analysis revealed that the abundance of many Calvin cycle intermediates is dramatically disturbed in heso1 urt1 ski2. Importantly, all these molecular and physiological defects were largely rescued by the loss-of-function mutation in RNA-DEPENDENT RNA POLYMERASE 6 (RDR6), demonstrating illegitimate siRNA-mediated TKL silencing. Taken together, our results suggest that HESO1- and URT1-mediated RNA uridylation connects to the cytoplasmic RNA degradation pathway for RNA surveillance, which is crucial for TKL expression and photosynthesis in Arabidopsis.

Neutrophil-associated Proteins as Novel Biomarkers Elevated in Cerebrospinal Fluid of Neurosyphilis Patients.

BACKGROUND: The immunopathological mechanisms underlying neurosyphilis remain incompletely elucidated, and the diagnosis of neurosyphilis presents challenges. METHODS: We used an antibody microarray to detect 640 proteins in cerebrospinal fluid (CSF) samples collected from 6 non-neurosyphilis and 10 neurosyphilis patients. The levels of CSF CXCL1, CXCL8, G-CSF, LCN2, MMP8, and MMP9 in 46 non-neurosyphilis, 51 untreated neurosyphilis, and 31 post-treatment neurosyphilis patients were quantified using enzyme-linked immunosorbent assay. The associations between the levels of these proteins and clinical parameters in neurosyphilis were evaluated using Spearman's analysis, and the diagnostic performance of these proteins in neurosyphilis was assessed using receiver operating characteristic curve. RESULTS: A total of 102 differentially expressed proteins between neurosyphilis and non-neurosyphilis were identified. The levels of significantly elevated neutrophil-associated proteins (CXCL1, CXCL8, G-CSF, LCN2, MMP8, and MMP9) in neurosyphilis were positive correlations with WBC counts, RPR titer, and protein concentration in CSF. The combination of CSF CXCL8, MMP9, and LCN2 yielded an AUC of 0.92 for diagnosing neurosyphilis, surpassing that of CSF RPR. CONCLUSIONS: CXCL1, CXCL8, G-CSF, LCN2, MMP8, and MMP9 could be associated with central nervous system damage of neurosyphilis. The combination of CSF CXCL8, MMP9, and LCN2 is a promising biomarker for diagnosing neurosyphilis.

Hematopoietic cytoplasmic adaptor protein Hem1 promotes osteoclast fusion and bone resorption in mice.

Hem1 (hematopoietic protein 1), a hematopoietic cell-specific member of the Hem family of cytoplasmic adaptor proteins, is essential for lymphopoiesis and innate immunity as well as for the transition of hematopoiesis from the fetal liver to the bone marrow. However, the role of Hem1 in bone cell differentiation and bone remodeling is unknown. Here, we show that deletion of Hem1 resulted in a markedly increase in bone mass because of defective bone resorption in mice of both sexes. Hem1-deficient osteoclast progenitors were able to differentiate into osteoclasts, but the osteoclasts exhibited impaired osteoclast fusion and decreased bone-resorption activity, potentially because of decreased mitogen-activated protein kinase and tyrosine kinase c-Abl activity. Transplantation of bone marrow hematopoietic stem and progenitor cells from wildtype into Hem1 knockout mice increased bone resorption and normalized bone mass. These findings indicate that Hem1 plays a pivotal role in the maintenance of normal bone mass.

Indobufen or Aspirin on Top of Clopidogrel After Coronary Drug-Eluting Stent Implantation (OPTION): A Randomized, Open-Label, End Point-Blinded, Noninferiority Trial.

BACKGROUND: Dual antiplatelet therapy (DAPT) with aspirin as a background therapy has become the standard care after percutaneous coronary intervention. However, some adverse noncardiac effects limited the use of aspirin in clinical practice. Thus, evaluation of pharmacological alternatives to aspirin is attractive. Previous data indicated that indobufen could lessen the unwanted side effects of aspirin while retaining the antithrombotic efficacy, but its combination with a P2Y12 inhibitor still lacks randomized clinical trial evidence. METHODS: In this randomized, open-label, noninferiority trial, patients with negative cardiac troponin undergoing coronary drug-eluting stent implantation were randomly assigned in a 1:1 ratio to receive either indobufen-based DAPT (indobufen 100 mg twice a day plus clopidogrel 75 mg/d for 12 months) or conventional DAPT (aspirin 100 mg/d plus clopidogrel 75 mg/d for 12 months). The primary end point was a 1-year composite of cardiovascular death, nonfatal myocardial infarction, ischemic stroke, definite or probable stent thrombosis, or Bleeding Academic Research Consortium criteria type 2, 3, or 5 bleeding. The end points were adjudicated by an independent Clinical Event Committee. RESULTS: Between January 11, 2018, and October 12, 2020, 4551 patients were randomized in 103 cardiovascular centers: 2258 patients to the indobufen-based DAPT group and 2293 to the conventional DAPT group. The primary end point occurred in 101 patients (4.47%) in the indobufen-based DAPT group and 140 patients (6.11%) in the conventional DAPT group (absolute difference, -1.63%; Pnoninferiority<0.001; hazard ratio, 0.73 [95% CI, 0.56-0.94]; P=0.015). Cardiovascular death, nonfatal myocardial infarction, ischemic stroke, and stent thrombosis were observed in 0.13%, 0.40%, 0.80%, and 0.22% of patients in the indobufen-based DAPT group and 0.17%, 0.44%, 0.83%, and 0.17% of patients in the conventional DAPT group (all P>0.05). The occurrence of Bleeding Academic Research Consortium criteria type 2, 3, or 5 bleeding events was lower in the indobufen-based DAPT group compared with the conventional DAPT group (2.97% versus 4.71%; hazard ratio, 0.63 [95% CI, 0.46-0.85]; P=0.002), with the main decrease in type 2 bleeding (1.68% versus 3.49%; hazard ratio, 0.48 [95% CI, 0.33-0.70]; P<0.001). CONCLUSIONS: In Chinese patients with negative cardiac troponin undergoing drug-eluting stent implantation, indobufen plus clopidogrel DAPT compared with aspirin plus clopidogrel DAPT significantly reduced the risk of 1-year net clinical outcomes, which was driven mainly by a reduction in bleeding events without an increase in ischemic events. REGISTRATION: URL: https://www.chictr.org.cn; Unique identifier: ChiCTR-IIR-17013505.

Omicron breakthrough infections after triple-dose inactivated COVID-19 vaccination: A comprehensive analysis of antibody and T-cell responses.

This study longitudinally evaluated the immune response in individuals over a year after receiving three doses of an inactivated SARS-CoV-2 vaccine, focusing on reactions to Omicron breakthrough infections. From 63 blood samples of 37 subjects, results showed that the third booster enhanced the antibody response against Alpha, Beta, and Delta VOCs but was less effective against Omicron. Although antibody titres decreased post-vaccination, SARS-CoV-2-specific T-cell responses, both CD4+ and CD8+, remained stable. Omicron breakthrough infections significantly improved neutralization against various VOCs, including Omicron. However, the boost in antibodies against WT, Alpha, Beta, and Delta variants was more pronounced. Regarding T cells, breakthrough infection predominantly boosted the CD8+ T-cell response, and the intensity of the spike protein-specific T-cell response was roughly comparable between WT and Omicron BA.5.

T cells in testicular germ cell tumors: new evidence of fundamental contributions by rare subsets.

BACKGROUND: Immune cell infiltration is heterogeneous but common in testicular germ cell tumors (TGCT) and pre-invasive germ cell neoplasia in situ (GCNIS). Tumor-infiltrating T cells including regulatory T (Treg) and follicular helper T (Tfh) cells are found in other cancer entities, but their contributions to TGCT are unknown. METHODS: Human testis specimens from independent patient cohorts were analyzed using immunohistochemistry, flow cytometry and single-cell RNA sequencing (scRNA-seq) with special emphasis on delineating T cell subtypes. RESULTS: Profound changes in immune cell composition within TGCT, shifting from macrophages in normal testes to T cells plus B and dendritic cells in TGCT, were documented. In most samples (96%), the CD4+ T cell frequency exceeded that of CD8+ cells, with decreasing numbers from central to peripheral tumor areas, and to tumor-free, contralateral testes. T cells including Treg and Tfh were most abundant in seminoma compared to mixed tumors and embryonal carcinoma. CONCLUSION: Despite considerable heterogeneity between patients, T cell subtypes form a key part of the TGCT microenvironment. The novel finding of rare Treg and Tfh cells in human testis suggests their involvement in TGCT pathobiology, with implications for understanding tumor progression, to assess patients' prognosis, and as putative targets for personalized immunotherapy.

Relevance of pyroptosis-associated genes in nasopharyngeal carcinoma diagnosis and subtype classification.

BACKGROUND: Nasopharyngeal carcinoma (NPC) is a highly aggressive and metastatic malignancy originating in the nasopharyngeal tissue. Pyroptosis is a relatively newly discovered, regulated form of necrotic cell death induced by inflammatory caspases that is associated with a variety of diseases. However, the role and mechanism of pyroptosis in NPC are not fully understood. METHODS: We analyzed the differential expression of pyroptosis-related genes (PRGs) between patients with and without NPC from the GSE53819 and GSE64634 datasets of the Gene Expression Omnibus (GEO) database. We mapped receptor operating characteristic profiles for these key PRGs to assess the accuracy of the genes for disease diagnosis and prediction of patient prognosis. In addition, we constructed a nomogram based on these key PRGs and carried out a decision curve analysis. The NPC patients were classified into different pyroptosis gene clusters by the consensus clustering method based on key PRGs, whereas the expression profiles of the key PRGs were analyzed by applying principal component analysis. We also analyzed the differences in key PRGs, immune cell infiltration and NPC-related genes between the clusters. Finally, we performed differential expression analysis for pyroptosis clusters and obtained differentially expressed genes (DEGs) and performed Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses. RESULTS: We obtained 14 differentially expressed PRGs from GEO database. Based on these 14 differentially expressed PRGs, we applied least absolute shrinkage and selection operator analysis and the random forest algorithm to obtain four key PRGs (CHMP7, IL1A, TP63 and GSDMB). We completely distinguished the NPC patients into two pyroptosis gene clusters (pyroptosis clusters A and B) based on four key PRGs. Furthermore, we determined the immune cell abundance of each NPC sample, estimated the association between the four PRGs and immune cells, and determined the difference in immune cell infiltration between the two pyroptosis gene clusters. Finally, we obtained and functional enrichment analyses 259 DEGs by differential expression analysis for both pyroptosis clusters. CONCLUSIONS: PRGs are critical in the development of NPC, and our research on the pyroptosis gene cluster may help direct future NPC therapeutic approaches.

Novel underlying regulatory mechanism of the MsDAD2-mediated salt stress response in alfalfa.

Alfalfa (Medicago sativa L.), a crucial and widely grown forage legume, faces yield and quality challenges due to salinity stress. The defender against apoptotic death (DAD) gene, recognized initially as an apoptosis suppressor in mammals, plays a pivotal role in catalyzing N-glycosylation, acting as a positive regulator for protein folding and endoplasmic reticulum (ER) export. Here, we found that the MsDAD2 gene was specially induced in the salt-tolerant alfalfa cultivar (DL) under salinity stress, but not in the salt-sensitive cultivar (SD). Overexpression of MsDAD2 enhanced the salinity resistance of transgenic alfalfa by promoting NAD(P)H-quinone oxidoreductase (NQO1) and cytochrome b6f complex subunit (Cyt b6/f) expression, thereby mitigating reactive oxygen species (ROS) production. ChIP-qPCR analysis suggested that the differential expression of MsDAD2 in DL and SD under salinity stress may be linked to dynamic histone modifications in its promoter. Therefore, our findings elucidate a novel regulatory mechanism of MsDAD2 in alfalfa's response to salinity stress, underscoring its significance as a target for alfalfa breeding to enhance salt tolerance.

Hippuric acid alleviates dextran sulfate sodium-induced colitis via suppressing inflammatory activity and modulating gut microbiota.

Inflammatory bowel disease (IBD) is a chronic inflammatory disease associated with metabolic disorder and gut dysbiosis. Decreased abundance of hippuric acid (HA) was found in patients with IBD. HA, metabolized directly from benzoic acid in the intestine and indirectly from polyphenols, serves as a marker of polyphenol catabolism. While polyphenols and benzoic acid have been shown to alleviate intestinal inflammation, the role of HA in this context remains unknown. Herein, we investigated the effects and mechanism of HA on DSS-induced colitis mice. The results revealed that HA alleviated clinical activity and intestinal barrier damage, decreased pro-inflammatory cytokine production. Metagenomic sequencing suggested that HA treatment restored the gut microbiota, including an increase in beneficial gut bacteria such as Adlercreutzia, Eubacterium, Schaedlerella and Bifidobacterium_pseudolongum. Furthermore, we identified 113 candidate genes associated with IBD that are potentially under HA regulation through network pharmacological analyses. 10 hub genes including ALB, IL-6, HSP90AA1, and others were identified using PPI analysis and validated using molecular docking and mRNA expression analysis. Additionally, KEGG analysis suggested that the renin-angiotensin system (RAS), NF-κB signaling and Rap1 signaling pathways were important pathways in the response of HA to colitis. Thus, HA may provide novel biotherapy options for IBD.

A Dual-Active Covalent Triazine Framework Film for Efficient Visible-Light-Driven Hydrogen Peroxide Production.

Photocatalytic hydrogen peroxide production from water and oxygen offers a clean and sustainable alternative to the conventional energy-intensive anthraquinone oxidation method. Compared to powdered covalent triazine frameworks (CTFs), the film morphology of CTFs provides better connectivity in 2D, yielding several advantages: more efficient connections between active sites, reduced electron-hole pair recombination, increased resistance to superoxide radical induced corrosion, and decreased light scattering. Leveraging these benefits, it has incorporated dual active sites for both the oxygen reduction reaction (ORR) and the water oxidation reaction (WOR) into a CTF film system. This dual-active CTF film demonstrated an exceptional hydrogen peroxide production rate of 19 460 µmol h⁻¹ m⁻2 after 1 h and 17 830 µmol h⁻¹ m⁻2 after 5 h under visible light irradiation (≥420 nm) without the need for sacrificial agents.

Tungstate Intercalated NiFe Layered Double Hydroxide Enables Long-Term Alkaline Seawater Oxidation.

Renewable electricity-driven seawater splitting presents a green, effective, and promising strategy for building hydrogen (H2)-based energy systems (e.g., storing wind power as H2), especially in many coastal cities. The abundance of Cl- in seawater, however, will cause severe corrosion of anode catalyst during the seawater electrolysis, and thus affect the long-term stability of the catalyst. Herein, seawater oxidation performances of NiFe layered double hydroxides (LDH), a classic oxygen (O2) evolution material, can be boosted by employing tungstate (WO4 2-) as the intercalated guest. Notably, insertion of WO4 2- to LDH layers upgrades the reaction kinetics and selectivity, attaining higher current densities with ≈100% O2 generation efficiency in alkaline seawater. Moreover, after a 350 h test at 1000 mA cm-2, only trace active chlorine can be detected in the electrolyte. Additionally, O2 evolution follows lattice oxygen mechanism on NiFe LDH with intercalated WO4 2-.

Recent Advances in RNA-Targeted Cancer Therapy.

Ribonucleic acid (RNA) plays a pivotal role in gene regulation and protein biosynthesis. Interfering the physiological function of key RNAs to induce cell apoptosis holds great promise for cancer treatment. Many RNA-targeted anti-cancer strategies have emerged continuously. Among them, RNA interference (RNAi) has been recognized as a promising therapeutic modality for various disease treatments. Nevertheless, the primary obstacle in siRNA delivery-escaping the endosome and crossing the plasma membrane severely impedes its therapeutic potential. Thus far, a variety of nanosystems as well as carrier-free bioconjugation for siRNA delivery have been developed and employed to enhance the drug delivery and anti-tumor efficiency. Besides, the use of small molecules to target specific RNA structures and disrupt their function, along with the covalent modification of RNA, has also drawn tremendous attention recently owing to high therapeutic efficacy. In this review, we will provide an overview of recent progress in RNA-targeted cancer therapy including various siRNA delivery strategies, RNA-targeting small molecules, and newly emerged covalent RNA modification. Finally, challenges and future perspectives faced in this research field will be discussed.

The epidemiology of pregnancy loss: global burden, variable risk factors, and predictions.

STUDY QUESTION: Is the incidence of pregnancy loss correlated with various geographic, socio-demographic, and age stratifications at the societal and national levels, and what are the risk factors associated with pregnancy loss at the individual level? SUMMARY ANSWER: The epidemiological trends and disease burden of pregnancy loss were correlated with various geographic, socio-demographic, and age stratifications, and we identified that poor health condition, smoking, sedentary behaviour, lower educational level, and lower maternal birth weight may significantly increase the risk of pregnancy loss. WHAT IS KNOWN ALREADY: Several studies have used national, regional, or single-centre data to describe trends in the burden of pregnancy loss, and previous observational studies have identified some variable factors possibly associated with pregnancy loss. However, a comprehensive analysis of global trends and predictions of pregnancy loss are lacking, and the conclusions have been inconsistent. STUDY DESIGN, SIZE, DURATION: We have utilized the data from Global Burden of Disease (GBD) 2019 to provide an overview of the trends in pregnancy loss in 204 countries and regions worldwide from 1990 to 2019, and have made a forecast for the next 10 years. Moreover, we applied a variety of statistical genetics methods to analyse 34 239 pregnancy loss and 89 340 non-pregnancy loss cases from the FinnGen consortium to comprehensively assess the bidirectional causality of variable factors with pregnancy loss from an individual perspective. PARTICIPANTS/MATERIALS, SETTING, METHODS: We analysed trends in the incidence, disability-adjusted life years (DALYs), and maternal mortality of pregnancy loss at global, regional, national, socio-demographic index (SDI), and age levels. The autoregressive integrated moving average (ARIMA) model was used to predict trends by 2030. Finally, we used two-sample Mendelian randomization (MR) and multivariate MR (MVMR) analyses to explore the relationship between the pregnancy loss and variables closely related to physical condition, physical activity, lifestyle, sleep conditions, basic conditions. MAIN RESULTS AND THE ROLE OF CHANCE: In 2019, there were approximately 42.39 million cases of pregnancy loss worldwide. Globally, the incidence, DALYs, and mortality of pregnancy loss showed a decreasing trend between 1990 and 2019, although the number was increasing in some countries. The age-standardized incidence, DALYs, and mortality rate were negatively correlated with SDI level and show a further decline by 2030. Based on MR analyses, we confirmed that genetically predicted overall health rating (inverse-variance weighted (IVW) odds ratio (OR), 1.68; 95% CI, 1.34-2.13; P = 5.10 × 10-6), smoking initiation (IVW OR, 1.26; 95% CI, 1.16-1.38; P = 1.90 × 10-9), sedentary behaviour (IVW OR, 1.56; 95% CI, 1.20-2.01; P = 2.76 × 10-5), educational level (IVW OR, 0.64; 95% CI, 0.55-0.73; P = 6.56 × 10-10), and maternal birth weight (IVW OR, 0.70; 95% CI, 0.58-0.85; P = 2.98 × 10-4) were significantly related to the risk of pregnancy loss, whereas body mass index (IVW OR, 1.10; 95% CI, 1.03-1.17; P = 5.31 × 10-3), alcohol consumption (IVW OR, 1.74; 95% CI, 1.03-2.95; P = 0.04), insomnia (IVW OR, 1.66; 95% CI, 1.14-2.42; P = 7.00 × 10-3), and moderate-to-vigorous physical activity (IVW OR, 0.59; 95% CI, 0.37-0.95; P = 2.85 × 10-2) were suggestively associated with the risk of pregnancy loss. These results were supported by sensitivity and directional analyses. LIMITATIONS, REASONS FOR CAUTION: Despite efforts to standardize GBD data from all over the world, uncertainties in data quality control regarding ascertainment of pregnancy loss, medical care accessibility, cultural differences, and socioeconomic status still exist. Furthermore, the population in the MRstudy was limited to Europeans, which means that the results may not be extrapolated to people of other origins. WIDER IMPLICATIONS OF THE FINDINGS: Our study provides for the first time an overview of the epidemiological trends and disease burden of pregnancy loss related with SDI, region, country, and age, and predicts changes in future trends up to 2030. In addition, findings support that genetic susceptibility, smoking, health condition, and sedentary behaviour may be powerful indicators of an increased risk of pregnancy loss. These results would be beneficial for policy makers of different countries and regions to improve prevention implementation. STUDY FUNDING/COMPETING INTERESTS: This work was supported by grants 2021JH2/10300093, from the Science and Technology Projects of Liaoning Province, China. All authors declare no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.