Causal effects of gut microbiota on autism spectrum disorder: A two-sample mendelian randomization study.

There is increasing evidence that alterations in gut microbiota (GM) composition are associated with autism spectrum disorder (ASD), but no reliable causal relationship has been established. Therefore, a 2-sample Mendelian randomization (MR) study was conducted to reveal a potential causal relationship between GM and ASD. Instrumental variables for 211 GM taxa were obtained from genome-wide association studies (GWAS) and Mendelian randomization studies to estimate their impact on ASD risk in the iPSYCH-PGC GWAS dataset (18,382 ASD cases and 27,969 controls). Inverse variance weighted (IVW) is the primary method for causality analysis, and several sensitivity analyses validate MR results. Among 211 GM taxa, IVW results confirmed that Tenericutes (P value = .0369), Mollicutes (P value = .0369), Negativicutes (P value = .0374), Bifidobacteriales (P value = .0389), Selenomonadales (P value = .0374), Bifidobacteriaceae (P value = .0389), Family XIII (P value = .0149), Prevotella7 (P value = .0215), Ruminococcaceae NK4A214 group (P value = .0205) were potential protective factors for ASD. Eisenbergiella (P value = .0159) was a possible risk factor for ASD. No evidence of heterogeneous, pleiotropic, or outlier single-nucleotide polymorphism was detected. Additionally, further sensitivity analysis verified the robustness of the above results. We confirm a potential causal relationship between certain gut microbes and ASD, providing new insights into how gut microbes mediate ASD. The association between them needs to be further explored and will provide new ideas for the prevention and treatment of ASD.

A novel SNP in HUWE1 promoter confers increased risk of NOA by affecting the RA/RARα pathway in Chinese individuals.

BACKGROUND: The ubiquitin ligase HECT, UBA, and WWE domain-containing E3 ubiquitin protein ligase 1 is essential for the establishment and maintenance of spermatogonia. However, the role of HECT, UBA, and WWE domain-containing E3 ubiquitin protein ligase 1 in regulating germ cell differentiation remains unclear, and clinical evidence linking HECT, UBA, and WWE domain-containing E3 ubiquitin protein ligase 1 to male infertility pathogenesis is lacking. OBJECTIVE: This study aims to investigate the role of HUWE1 in germ cell differentiation and the mechanism by which a HUWE1 single nucleotide polymorphism increases male infertility risk. MATERIALS AND METHODS: We analyzed HUWE1 single nucleotide polymorphisms in 190 non-obstructive azoospermia patients of Han Chinese descent. We evaluated HECT, UBA, and WWE domain-containing E3 ubiquitin protein ligase 1 regulation by retinoic acid receptor alpha using chromatin immunoprecipitation assays, electrophoretic mobility shift assays, and siRNA-mediated RARα knockdown. Using C18-4 spermatogonial cells, we determined whether HECT, UBA, and WWE domain-containing E3 ubiquitin protein ligase 1 participated in retinoic acid-mediated retinoic acid receptor alpha signaling. We performed luciferase assays, cell counting kit-8 assays, immunofluorescence, quantitative real-time polymerase chain reaction, and western blotting. We quantified HUWE1 and retinoic acid receptor alpha in testicular biopsies from non-obstructive azoospermia and obstructive azoospermia patients using quantitative real-time polymerase chain reaction and immunofluorescence. RESULTS: Three HUWE1 single nucleotide polymorphisms were significantly associated with spermatogenic failure in 190 non-obstructive azoospermia patients; one (rs34492591) was in the HUWE1 promoter. Retinoic acid receptor alpha regulates HUWE1 gene expression by binding to its promoter. HECT, UBA, and WWE domain-containing E3 ubiquitin protein ligase 1 participates in retinoic acid/retinoic acid receptor alpha signaling pathway and regulates the expression of germ cell differentiation genes STRA8 and SCP3 to inhibit cell proliferation and reduce γH2AX accumulation. Notably, significantly lower levels of HUWE1 and RARα were detected in testicular biopsy samples from non-obstructive azoospermia patients. CONCLUSIONS: An HUWE1 promoter single nucleotide polymorphism significantly downregulates its expression in non-obstructive azoospermia patients. Mechanistically, HECT, UBA, and WWE domain-containing E3 ubiquitin protein ligase 1 regulates germ cell differentiation during meiotic prophase through its participation in retinoic acid/retinoic acid receptor alpha signaling and subsequent modulation of γH2AX. Taken together, these results strongly suggest that the genetic polymorphisms of HUWE1 are closely related to spermatogenesis and non-obstructive azoospermia pathogenesis.

Dissecting Sperm Mitochondrial G-Quadruplex Structures Using a Fluorescent Probe Biomarker to Monitor and Regulate Fertilization Capability.

To monitor the levels of mitochondrial DNA G-quadruplexes (mtDNA G4s) in spermatozoa and to explore the possibility using mtDNA G4s as a reliable marker in patients with multiple clinical insemination failures, a novel chemical TPE-mTO probe engineered in our previous work was used on both samples from the mice sperm and from patients with fertilization failure. Expression of valosin-containing protein and the zona-free hamster egg assay were used to evaluate mitophagy and human sperm penetration. RNA-sequencing was used to explore expression changes of key genes affected by mtDNA G4s. Results showed that the probe can track mtDNA G4s in spermatozoa easily and quickly with fewer backgrounds. Significantly increased mtDNA G4s were also found in patients with fertilization failure, using the flow-cytometry-based TPE-mTO probe detection method. A sperm-hamster egg penetration experiment showed that abnormal fertilization caused by increased mtDNA G4s can be effectively restored by a mitophagy inducer. This study provides a novel method for monitoring etiological biomarkers in patients with clinical infertility and treatment for patients with abnormal fertilization caused by mtDNA G4 dysfunction.

[Analysis of NSD1 gene variant in a child with autism spectrum disorder in conjunct with congenital heart disease].

OBJECTIVE: To explore the clinical characteristics and genetic basis of a child with autism spectrum disorder (ASD) in conjunct with congenital heart disease (CHD). METHODS: A child who was hospitalized at the Third People's Hospital of Chengdu on April 13, 2021 was selected as the study subject. Clinical data of the child were collected. Peripheral blood samples of the child and his parents were collected and subjected to whole exome sequencing (WES). A GTX genetic analysis system was used to analyze the WES data and screen candidate variants for ASD. Candidate variant was verified by Sanger sequencing and bioinformatics analysis. Real-time fluorescent quantitative PCR (qPCR) was carried out to compare the expression of mRNA of the NSD1 gene between this child and 3 healthy controls and 5 other children with ASD. RESULTS: The patient, an 8-year-old male, has manifested with ASD, mental retardation and CHD. WES analysis revealed that he has harbored a heterozygous c.3385+2T>C variant in the NSD1 gene, which may affect the function of its protein product. Sanger sequencing showed that neither of his parent has carried the same variant. By bioinformatic analysis, the variant has not been recorded in the ESP, 1000 Genomes and ExAC databases. Analysis with Mutation Taster online software indicated it to be disease causing. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was predicted to be pathogenic. By qPCR analysis, the expression level of mRNA of the NSD1 gene in this child and 5 other children with ASD was significantly lower than that of the healthy controls (P < 0.001). CONCLUSION: The c.3385+2T>C variant of the NSD1 gene can significantly reduce its expression, which may predispose to ASD. Above finding has enriched the mutational spectrum the NSD1 gene.

A loss-of-function variant in SSFA2 causes male infertility with globozoospermia and failed oocyte activation.

Globozoospermia (OMIM: 102530) is a rare type of teratozoospermia (< 0.1%). The etiology of globozoospermia is complicated and has not been fully revealed. Here, we report an infertile patient with globozoospermia. Variational analysis revealed a homozygous missense variant in the SSFA2 gene (NM_001130445.3: c.3671G > A; p.R1224Q) in the patient. This variant significantly reduced the protein expression of SSFA2. Immunofluorescence staining showed positive SSFA2 expression in the acrosome of human sperm. Liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) and Coimmunoprecipitation (Co-IP) analyses identified that GSTM3 and Actin interact with SSFA2. Further investigation revealed that for the patient, regular intracytoplasmic sperm injection (ICSI) treatment had a poor prognosis. However, Artificial oocyte activation (AOA) by a calcium ionophore (A23187) after ICSI successfully rescued the oocyte activation failure for the patient with the SSFA2 variant, and the couple achieved a live birth. This study revealed that SSFA2 plays an important role in acrosome formation, and the homozygous c.3671G > A loss-of-function variant in SSFA2 caused globozoospermia. SSFA2 may represent a new gene in the genetic diagnosis of globozoospermia, especially the successful outcome of AOA-ICSI treatment for couples, which has potential value for clinicians in their treatment regimen selections.

Activation of PTH1R alleviates epididymitis and orchitis through Gq and ß-arrestin-1 pathways.

Inflammation in the epididymis and testis contributes significantly to male infertility. Alternative therapeutic avenues treating epididymitis and orchitis are expected since current therapies using antibiotics have limitations associated to side effects and are commonly ineffective for inflammation due to nonbacterial causes. Here, we demonstrated that type 1 parathyroid hormone receptor (PTH1R) and its endogenous agonists, parathyroid hormone (PTH) and PTH-related protein (PTHrP), were mainly expressed in the Leydig cells of testis as well as epididymal epithelial cells. Screening the secretin family G protein-coupled receptor identified that PTH1R in the epididymis and testis was down-regulated in mumps virus (MuV)- or lipopolysaccharide (LPS)-induced inflammation. Remarkably, activation of PTH1R by abaloparatide (ABL), a Food and Drug Administration-approved treatment for postmenopausal osteoporosis, alleviated MuV- or LPS-induced inflammatory responses in both testis and epididymis and significantly improved sperm functions in both mouse model and human samples. The anti-inflammatory effects of ABL were shown to be regulated mainly through the Gq and ß-arrestin-1 pathway downstream of PTH1R as supported by the application of ABL in Gnaq± and Arrb1-/- mouse models. Taken together, our results identified an important immunoregulatory role for PTH1R signaling in the epididymis and testis. Targeting to PTH1R might have a therapeutic effect for the treatment of epididymitis and orchitis or other inflammatory disease in the male reproductive system.

Association of Zinc deficiency, oxidative stress and increased double-stranded DNA breaks in globozoospermic infertile patients and its implication for the assisted reproductive technique.

BACKGROUND: Sperm DNA fragmentation and its adverse impact on outcomes of assisted reproductive techniques (ART) in globozoospermic infertile patients has been previously reported. However, the association of Zinc element with DNA damage and intracytoplasmic sperm injection (ICSI) outcome in globozoospermic infertile patients remains unclear. METHODS: Using flame atomic absorption spectrophotometer and superoxide dismutase (SOD) assay, the levels of Cu, Fe, Mn, Zn and SOD activities in seminal plasma from both globozoospermic infertile patients and fertile volunteers were tested respectively. Using sperm chromatin dispersion (SCD) test and Comet assay, the DNA damages in their semen samples from the two groups was detected. In addition, using Aniline Blue staining, their sperm nucleus maturations were also examined. RESULTS: The levels of seminal Zinc and SOD activities were lower in the globozoospermic infertile patients and the double-stranded break DFI (DSB-DFI) were significantly higher than that in the fertile controls. Antioxidative insufficiency of SOD with a low Zn level might be responsible for oxidative stress, which may lead to DNA damage in globozoospermic spermatozoa. Zn deficiency might also have influence on the chromatin stabilization of globozoospermic spermatozoa during spermiogenesis, causing its more vulnerable to oxidative attack. CONCLUSIONS: Serious DSBs in globozoospermia and antioxidative insufficiency due to Zinc element deficiency in spermatozoa might be responsible for the failure of ICSI in globozoospermia.