Biology subjects

Wang, B.

Publications and source records attributed to Wang, B..

At least 325 records · Page 18Linked to original sources

bioRxiv2024

Microbiome-induced Increases and Decreases in Bone Tissue Strength can be Initiated After Skeletal Maturity

Recent studies in mice have indicated that the gut microbiome can regulate bone tissue strength. However, prior work involved modifications to the gut microbiome in growing animals and it is unclear if the same changes in the microbiome, applied later in life, would change matrix strength. Here we changed the composition of the gut microbiome before and/or after skeletal maturity (16 weeks of age) using oral antibiotics (ampicillin + neomycin). Male and female mice (n=143 total, n=12-17/group/sex) were allocated into five study groups:1) Unaltered, 2) Continuous (dosing 4-24 weeks of age), 3) Delayed (dosing only 16-24 weeks of age), 4) Initial (dosing 4-16 weeks of age, suspended at 16 weeks), and 5) Reconstituted (dosing from 4-16 weeks following by fecal microbiota transplant from Unaltered donors). Animals were euthanized at 24 weeks of age. In males, bone matrix strength in the femur was 25-35% less than expected from geometry in mice from the Continuous (p= 0.001), Delayed (p= 0.005), and Initial (p=0.040) groups as compared to Unaltered. Reconstitution of the gut microbiota, however, led to a bone matrix strength similar to Unaltered animals (p=0.929). In females, microbiome-induced changes in bone matrix strength followed the same trend as males but were not significantly different, demonstrating sex-related differences in the response of bone matrix to the gut microbiota. Minor differences in chemical composition of bone matrix were observed (Raman spectroscopy). Our findings indicate that microbiome-induced impairment of bone matrix in males can be initiated and/or reversed after skeletal maturity. The portion of the femoral cortical bone formed after skeletal maturity (16 weeks) is small; however, this suggests that microbiome-induced changes in bone matrix occur without osteoblast/osteoclast turnover using an, as of yet unidentified mechanism. These findings add to evidence that the mechanical properties of bone matrix can be altered in the adult skeleton.

bioengineering↗

bioRxiv2023

Aberrant connective tissue sheath contraction drives premature hair follicle regression by inducing progenitor cell depletion in androgenetic alopecia

Androgenetic alopecia (AGA) is characterized by progressive miniaturization of hair, forming a distinctive patterned baldness in the scalp; yet, the mechanisms for hair miniaturization in this disease remain largely unknown. Here by single-cell transcriptome analysis, we describe a concise single-cell atlas, and identify the early changes in cell subpopulations, hair follicle (HF) stem cell fate determination and cell-cell communications in AGA anagen HF units. Thereinto, apoptotic loss of HF progenitor cells is significantly increased, correlated with HF miniaturization in AGA. Mechanistically, enhanced contraction of connective tissue sheath (CTS) activates the mechanosensitive channel PIEZO1, which triggers ectopic apoptosis of progenitor cells in human anagen HFs. Continuous CTS contraction during AGA causes long-term loss of progenitor cells via inducing persistent ectopic apoptosis through PIEZO1, eventually leading to premature hair regression. Most importantly, we show that targeting CTS contraction by ML-7, a selective myosin light chain kinase (MLCK) inhibitor, can obviously improve the growth of HFs from balding scalps of AGA patients. Our study reveals the cellular hierarchies and identifies CTS with increased muscle contraction activity as a driver of premature hair regression in AGA, highlighting CTS surrounding human HF as the therapeutic target for treating this disorder.

pathology↗

bioRxiv2023

Virus-like DNA tracers for characterizing wastewater-based pathogen monitoring systems

Wastewater-based pathogen monitoring has recently become a ubiquitous method for tracking the abundance and evolution of pathogens in a community or port of entry. But accurate inference of disease incidence from wastewater remains challenging, in large part due to noise and bias arising from wastewater transport and measurement. We developed a new system of tracer particles designed to enhance wastewater monitoring of viral pathogens. These tracers, which consist of synthetic DNA barcodes packaged into non-infectious viral capsids, can be deposited at known amounts and times into the sewer system and measured in wastewater samples to assess features such as assay sensitivity, and the decay and delay in viral signal arising from a shedding event. Here we describe the design, construction, and initial characterization of a 25-plex tracer library. Our tracer library supports simultaneous measurement of up to 5 distinct tracers by qPCR and up to 25 distinct tracers by amplicon or metagenomic sequencing. We demonstrate experimentally that the tracers are biologically inert and exhibit good stability and qPCR-assay performance in wastewater. These features collectively suggest that barcoded, virus-like tracers have the required properties for high-accuracy, high-resolution characterization of wastewater monitoring systems.

synthetic biology↗

bioRxiv2023

Autism genes converge on microtubule biology and RNA-binding proteins during excitatory neurogenesis

Recent studies have identified over one hundred high-confidence (hc) autism spectrum disorder (ASD) genes. Systems biological and functional analyses on smaller subsets of these genes have consistently implicated excitatory neurogenesis. However, the extent to which the broader set of hcASD genes are involved in this process has not been explored systematically nor have the biological pathways underlying this convergence been identified. Here, we leveraged CROP-Seq to repress 87 hcASD genes in a human in vitro model of cortical neurogenesis. We identified 17 hcASD genes whose repression significantly alters developmental trajectory and results in a common cellular state characterized by disruptions in proliferation, differentiation, cell cycle, microtubule biology, and RNA-binding proteins (RBPs). We also characterized over 3,000 differentially expressed genes, 286 of which had expression profiles correlated with changes in developmental trajectory. Overall, we uncovered transcriptional disruptions downstream of hcASD gene perturbations, correlated these disruptions with distinct differentiation phenotypes, and reinforced neurogenesis, microtubule biology, and RBPs as convergent points of disruption in ASD.

systems biology↗

bioRxiv2023

Latent Dirichlet Allocation Mixture Models for Nucleotide Sequence Analysis

Strings of nucleotides that carry biological information are typically described using sequence motifs that can be represented by weight matrices or consensus sequences. However, many biological signals in DNA or RNA are recognized by multiple factors in temporal sequence, consist of a mixture of sometimes dissimilar alternative motifs, or may be described better by base composition. Here we apply the Latent Dirichlet Allocation (LDA) mixture model to nucleotide sequences, using k-mers as features, in three related approaches. First, positions in aligned sequences are used as samples. Alternatively, whole sequences are used as samples, either with positional k-mers or with bulk k-mers occurring throughout the sequence. LDA readily identifies motifs, including such elusive cases as the intron branch site. LDA can also identify subtypes of sequence, such as splice site subtypes enriched in long vs. short introns, and can reliably distinguish such properties as reading frame or species of origin. Our results show that LDA is a useful model for describing heterogeneous signals, for assigning individual sequences to subtypes, and for identifying and characterizing sequences that do not fit recognized subtypes. Because LDA topic models are interpretable, they also aid the discovery of new motifs, even those present in a small fraction of samples, allowing a user to hypothesize potential regulatory factors. In summary, LDA can identify and characterize signals in nucleotide sequences and is useful for identifying candidate regulatory factors involved in complex biological processes.

bioinformatics↗

bioRxiv2023

Targeting endothelial FOXO1 protects diabetic β-cells and improves wound healing

The forkhead box O1 (FOXO1) transcription factor plays critical roles in regulating not only metabolic activity but also angiogenesis in the vascular endothelium1-4. Our previous studies show that epsin endocytic adaptors can regulate both angiogenesis and lymphangiogenesis5-7. Endothelial cells (ECs) lining the inside of blood vessels are continuously exposed to circulating insulin and insulin-like growth factors (IGFs). Emerging evidences suggest that ECs can affect {beta}-cell function8-11. Excessive IGF2, especially elevated local IGF2 levels in islets, may represent a risk factor for developing diabetes12-15; however, the underlying molecular mechanisms by which aberrant angiogenesis and endothelium-derived factors regulate pancreatic {beta}-cell function in diabetes remain unclear. Here, we report that the pancreas of diabetic patients as well as the pancreas, skin, and plasma of streptozotocin/high fat diet (STZ/HFD)-induced diabetic mice and db/db mice contains excess IGF2, which can lead to {beta}-cell dysfunction and apoptosis. Single-cell transcriptomics combined with mass spectrometry analysis reveal that endothelial-specific knockout of FOXO1 increases circulating soluble and cell-membrane or intracellular expression levels of IGF type 2 receptor (IGF2R) and CCCTC-binding factor (CTCF), while decreasing IGF2 levels in diabetes. Both IGFR215-17 and CTCF18-21 can reduce IGF2 levels and may ameliorate {beta}-cell decline associated with excess IGF2 in diabetes. Furthermore, depletion of FOXO1, epsins, or knockdown of ULK1 inhibits autophagy formation in ECs, preventing degradation of vascular endothelial growth factor receptor 2 (VEGFR2) to promote angiogenesis and improve wound healing in diabetes. Our findings reveal that endothelial FOXO1 regulates epsin-dependent angiogenesis and affects {beta}-cell function and fate through CTCF and IGF2-IGF2R, providing a potential strategy for ameliorating diabetes and accelerating cutaneous wound healing.

cell biology↗

bioRxiv2023

A foundational atlas of autism protein interactions reveals molecular convergence

Translating high-confidence (hc) autism spectrum disorder (ASD) genes into viable treatment targets remains elusive. We constructed a foundational protein-protein interaction (PPI) network in HEK293T cells involving 100 hcASD risk genes, revealing over 1,800 PPIs (87% novel). Interactors, expressed in the human brain and enriched for ASD but not schizophrenia genetic risk, converged on protein complexes involved in neurogenesis, tubulin biology, transcriptional regulation, and chromatin modification. A PPI map of 54 patient-derived missense variants identified differential physical interactions, and we leveraged AlphaFold-Multimer predictions to prioritize direct PPIs and specific variants for interrogation in Xenopus tropicalis and human forebrain organoids. A mutation in the transcription factor FOXP1 led to reconfiguration of DNA binding sites and altered development of deep cortical layer neurons in forebrain organoids. This work offers new insights into molecular mechanisms underlying ASD and describes a powerful platform to develop and test therapeutic strategies for many genetically-defined conditions.

systems biology↗

bioRxiv2023

Multivariate Pattern Analysis of EEG Reveals Neural Mechanism of Naturalistic Target Processing in Attentional Blink

The human brain has inherent limitations in consciously processing visual information. When individuals monitor a rapid sequence of images for detecting two targets, they often miss the second target (T2) if it appears within a short time frame of 200-500ms after the first target (T1), a phenomenon known as the attentional blink (AB). The neural mechanism behind AB remains unclear, largely due to the use of simplistic visual items such as letters and digits in conventional AB experiments, which differ significantly from naturalistic vision. This study employed advanced multivariate pattern analysis (MVPA) of human EEG data to explore the neural representations associated with target processing within a naturalistic paradigm under conditions where AB does or does not occur. Our MVPA analysis successfully decoded the identity of target images from EEG data. Moreover, in the AB condition, characterized by a limited time between targets, T1 processing coincided with T2 processing, resulting in the suppression of late representational markers of both T1 and T2. Conversely, in the condition with longer inter-target interval, neural representations endured for a longer duration. These findings suggest that the attentional blink can be attributed to the suppression of neural representations in the later stages of target processing. Significance StatementWithin a naturalistic paradigm, we investigated the phenomenon known as attentional blink, where individuals struggle to identify a second target in a rapid sequence when the first target precedes it too closely. Attentional blink is purported to reflect an apparent bottleneck in the attention systems ability to rapidly redirect attentional resources; however, the mechanism underlying this phenomenon remains hotly debated. Our findings reveal that during a rapid presentation of natural images, a short temporal gap between targets results in reduced neural representations of targets and the occurrence of attentional blink. Conversely, when a greater temporal gap exists between targets, neural representations are preserved. This study provides valuable insights into how the human brain perceives the ever-changing visual world around us.

neuroscience↗

bioRxiv2023

Acetylation of WCC is dispensable for the core circadianclock but differentially regulates acute light responses in Neurospora

In the Neurospora circadian system, the White Collar Complex (WCC) formed by WC-1 and WC-2 drives expression of the frequency (frq) gene whose product FRQ feedbacks to inhibit transcriptional activity of WCC. Phosphorylation of WCC has been extensively studied, but the extent and significance of other post-translational modifications (PTM) has been poorly studied. To this end, we used mass-spectrometry to study alkylation sites on WCC, resulting in discovery of nine acetylation sites. Mutagenesis analysis showed most of the acetylation events individually do not play important roles in period determination. Moreover, mutating all the lysines falling in either half of WC-1 or all the lysine residues in WC-2 to arginines did not abolish circadian rhythms. In addition, we also found nine mono-methylation sites on WC-1, but like acetylation, individual ablation of most of the mono-methylation events did not result in a significant period change. Taken together, the data here suggest that acetylation or mono-methylation on WCC is not a determinant of the pace of the circadian feedback loop. The finding is consistent with a model in which repression of WCCs circadian activity is controlled mainly by phosphorylation. Interestingly, light-induced expression of some light-responsive genes has been modulated in certain wc-1 acetylation mutants, suggesting that WC-1 acetylation events differentially regulate light responses.

biochemistry↗

bioRxiv2023

A genome-wide association study of neonatal metabolites

The hereditary component significantly influences the concentration of metabolites in adults. Nevertheless, the precise influence of genetic factors on neonatal metabolites remains uncertain. To bridge this gap, we employed genotype imputation techniques on large-scale low-pass genome data obtained from non-invasive prenatal testing. Subsequently, we conducted association studies on a total of 75 metabolic components in neonates. The study identified a total 17 previous reported associations and 13 novel discovered associations between single nucleotide polymorphisms and metabolic components. These associations were initially found in the discovery cohort (8,744 participants) and subsequently confirmed in a replication cohort (19,041 participants). The average heritability of metabolic components was calculated to be 76.2%, with a range of 69-78.8%. The aforementioned findings offer valuable insights pertaining to the genetic architecture of neonatal metabolism. In BriefLarge-scale genomes of maternal non-invasive prenatal testing provide insights into the genetic contribution to neonatal metabolism. HighlightsGWAS of 27,785 low-pass genomes revealed 13 novel associations of neonatal metabolic components. Estimated an average of 76.2% heritability of neonatal metabolic components and showed the individual concentration can be accurately predicted from polygenic risk scores. A total of 17 established relationships have been observed, providing evidence that maternal genomes can be utilized in neonatal metabolite GWAS.

genetics↗

bioRxiv2023

SCC3 acts as the cohesin and inhibits inter-sister chromatids repair during rice meiosis

Cohesin is a multi-subunit protein that plays a pivotal role in holding sister chromatids together during cell division. Sister chromatid cohesion 3 (SCC3), constituents of cohesin complex, is highly conserved from yeast to mammals. Since the deletion of individual cohesin subunit always causes lethality, it is difficult to dissect its biological function in both mitosis and meiosis. Here, we obtained scc3 weak mutants using CRISPR-Cas9 system to explore its function during rice mitosis and meiosis. The scc3 weak mutants displayed obvious vegetative defects and complete sterility, underscoring the essential roles of SCC3 in both mitosis and meiosis. SCC3 is localized on chromatin from interphase to prometaphase in mitosis. However, in meiosis, SCC3 acts as an axial element during early prophase I and subsequently situates onto centromeric regions following the disassembly of the synaptonemal complex. The loading of SCC3 onto meiotic chromosomes depends on REC8. scc3 shows severe defects in homologous pairing and synapsis. Consequently, SCC3 functions as an axial element that is essential for maintaining homologous chromosome pairing and synapsis during meiosis.

genetics↗

bioRxiv2023

Cardiac Molecular Analysis Reveals Aging-Associated Metabolic Alterations Promoting Glycosaminoglycans Accumulation Via Hexosamine Biosynthetic Pathway

Age is a prominent risk factor for cardiometabolic disease, and often leads to heart structural and functional changes. However, precise molecular mechanisms underlying cardiac remodeling and dysfunction resulting from physiological aging per se remain elusive. Understanding these mechanisms requires biological models with optimal translation to humans. Previous research demonstrated that baboons undergo age-related reduction in ejection fraction and increased heart sphericity, mirroring changes observed in humans. The goal of this study was to identify early cardiac molecular alterations that precede functional adaptations, shedding light on the regulation of age-associated changes. We performed unbiased transcriptomics of left ventricle (LV) samples from female baboons aged 7.5-22.1 years (human equivalent [~]30-88 years). Weighted-gene correlation network and pathway enrichment analyses were performed to identify potential age-associated mechanisms in LV, with histological validation. Myocardial modules of transcripts negatively associated with age were primarily enriched for cardiac metabolism, including oxidative phosphorylation, tricarboxylic acid cycle, glycolysis, and fatty-acid {beta}-oxidation. Transcripts positively correlated with age suggest upregulation of glucose uptake, pentose phosphate pathway, and hexosamine biosynthetic pathway (HBP), indicating a metabolic shift towards glucose-dependent anabolic pathways. Upregulation of HBP commonly results in increased glycosaminoglycan precursor synthesis. Transcripts involved in glycosaminoglycan synthesis, modification, and intermediate metabolism were also upregulated in older animals, while glycosaminoglycan degradation transcripts were downregulated with age. These alterations would promote glycosaminoglycan accumulation, which was verified histologically. Upregulation of extracellular matrix (ECM)-induced signaling pathways temporally coincided with glycosaminoglycan accumulation. We found a subsequent upregulation of cardiac hypertrophy-related pathways and an increase in cardiomyocyte width. Overall, our findings revealed a transcriptional shift in metabolism from catabolic to anabolic pathways that leads to ECM glycosaminoglycan accumulation through HBP prior to upregulation of transcripts of cardiac hypertrophy-related pathways. This study illuminates cellular mechanisms that precede development of cardiac hypertrophy, providing novel potential targets to remediate age-related cardiac diseases.

molecular biology↗

bioRxiv2023

Unveiling the neural dynamics of conscious perception in rapid object recognition

Our brain excels at recognizing objects, even when they flash by in a rapid sequence. However, the neural processes determining whether a target image in a rapid sequence can be recognized or not remained elusive. We used electroencephalography (EEG) to investigate the temporal dynamics of brain processes that shape perceptual outcomes in these challenging viewing conditions. Using naturalistic images and advanced multivariate pattern analysis (MVPA) techniques, we probed the brain dynamics governing conscious object recognition. Our results show that although initially similar, the processes for when an object can or cannot be recognized diverge around 180ms post-appearance, coinciding with feedback neural processes. Decoding analyses indicate that object categorization can occur at [~]120ms through feedforward mechanisms. In contrast, object identification is resolved at [~]190ms after target onset, suggesting involvement of recurrent processing. These findings underscore the importance of recurrent neural connections in object recognition and awareness in rapid visual presentations.

neuroscience↗

bioRxiv2023

Genome folding principles revealed in condensin-depleted mitotic chromosomes

During mitosis, condensin activity interferes with interphase chromatin structures. Here, we generated condensin-free mitotic chromosomes to investigate genome folding principles. Co- depletion of condensin I and II, but neither alone, triggered mitotic chromosome compartmentalization in ways that differ from interphase. Two distinct euchromatic compartments, indistinguishable in interphase, rapidly emerged upon condensin loss with different interaction preferences and dependence on H3K27ac. Constitutive heterochromatin gradually self-aggregated and co-compartmentalized with the facultative heterochromatin, contrasting with their separation during interphase. While topologically associating domains (TADs) and CTCF/cohesin mediated structural loops remained undetectable, cis-regulatory element contacts became apparent, providing an explanation for their quick re-establishment during mitotic exit. HP1 proteins, which are thought to partition constitutive heterochromatin, were absent from mitotic chromosomes, suggesting, surprisingly, that constitutive heterochromatin can self-aggregate without HP1. Indeed, in cells traversing from M- to G1-phase in the combined absence of HP1, HP1{Pi} and HP1{gamma}, re-established constitutive heterochromatin compartments normally. In sum, "clean-slate" condensin-deficient mitotic chromosomes illuminate mechanisms of genome compartmentalization not revealed in interphase cells.

genomics↗

bioRxiv2023

Targeting CD74-positive macrophages improves neoadjuvant therapy in cervical cancer as revealed by single-cell transcriptomics analysis

Uterine cervical cancer (UCC) has the second-highest mortality rate among malignant tumors of the female reproductive system. Immune checkpoint inhibitors (ICIs) have emerged as a promising therapeutic strategy for cervical cancer. However, the efficacy of PD-1 (programmed cell death protein 1) blockade combined with neoadjuvant chemotherapy (NACT) and the ensuing alterations within the tumor microenvironment need further investigation. We conducted single-cell RNA sequencing using 46,950 cells from nine sequential human cervical cancer tissues representing different stages of NACT and PD-1 blockade combination therapy. We delineated the trajectory of cervical epithelial cells and unveiled crucial factors involved in the combination therapy. Cell communication analysis revealed the inferred interaction strength decreased between T cell-cancer cells, while the communication between macrophage-cancer cells intensified after NACT therapy. We verified that macrophages are necessary for PD-1 blockade combination to exert antitumor effects in vitro. Detailed analysis unraveled the CD74-positive macrophages frequently interacted with the immunoreactive Epi 3 subgroup during neoadjuvant combination therapy. CD74 upregulation limited phagocytosis and stimulated M2 polarization. The CD74 blockade enhanced macrophage phagocytosis, resulting in decreased viability of cervical cancer cells in vitro and in vivo. This study unveils the dynamic microenvironment of UCC influenced by NACT and PD-1 blockade combination therapy, and targeting CD74 was a potential strategy to augment the therapy efficacy.

cancer biology↗

bioRxiv2023

Sample-efficient Antibody Design through Protein Language Model for Risk-aware Batch Bayesian Optimization

Antibody design is a time-consuming and expensive process that often requires extensive experimentation to identify the best candidates. To address this challenge, we propose an efficient and risk-aware antibody design framework that leverages protein language models (PLMs) and batch Bayesian optimization (BO). Our framework utilizes the generative power of protein language models to predict candidate sequences with higher naturalness and a Bayesian optimization algorithm to iteratively explore the sequence space and identify the most promising candidates. To further improve the efficiency of the search process, we introduce a risk-aware approach that balances exploration and exploitation by incorporating uncertainty estimates into the acquisition function of the Bayesian optimization algorithm. We demonstrate the effectiveness of our approach through experiments on several benchmark datasets, showing that our framework outperforms state-of-the-art methods in terms of both efficiency and quality of the designed sequences. Our framework has the potential to accelerate the discovery of new antibodies and reduce the cost and time required for antibody design.

bioinformatics↗

bioRxiv2023

Force and the α-C-terminal domains bias RNApolymerase recycling

After RNA polymerase (RNAP) reaches a terminator, instead of dissociating from the template, it may diffuse along the DNA before restarting RNA synthesis from the previous or a different promoter. We monitored such secondary transcription using magnetic tweezers to determine the effect of low forces, protein roadblocks, and transcription factors. Up to 60% of RNAPs diffused along the DNA after termination. Force biased the direction of diffusion (sliding) and the velocity increased rapidly with force up to 0.7 pN and much more slowly thereafter. Sigma factor 70 ({sigma}70) likely remained bound to these sliding RNAPs, enabling recognition of secondary promoters and additional rounds of transcription, and the addition of elongation factor NusG, which competes with{sigma} 70 for binding to RNAP, limited additional rounds of transcription. Surprisingly, RNAP blocked by a DNA-bound lac repressor could slowly re-initiate transcription at the block-age and was not affected by NusG, suggesting a{sigma} -independent pathway. Force biased the frequency of encounters between convergent or divergent promoters such that transcription was repetitive only from the promoter opposing the direction of force. Sliding RNAP recognized and could subsequently re-initiate from promoters in either orientation. However, deletions of the -C-terminal domains severely limited the ability of RNAP to turn around.

biophysics↗

bioRxiv2023

Berberine impairs spermatogenesis in mice by modulating ornithine metabolism via gut microbiota regulation

Berberine (BBR) is used to treat diarrhea clinically, its reproductive toxicity, however, is poorly documented. This study aims to investigate the impact of BBR on the male reproductive system. Gradient doses of BBR were administered orally to experimental mice for consecutive 14 days. The gut microbiota, sperm concentration of cauda epididymis, and serum testosterone levels were measured after the last dose for assessing the effects of BBR. Moreover, the metabolome and transcriptome of the mice and microbiota were also investigated. Intragastric BBR administration resulted in a significant decrease in serum testosterone levels and epididymal sperm concentration in mice, which was attributed to a dramatic decrease of Muribaculaceae abundance in the gut microbiota of mice. Both fecal microbiota transplantation (FMT) and polyethylene glycol (PEG) treatment experiments also demonstrated that Muribaculaceae is necessary for spermatogenesis. Metabolomic analysis revealed that BBR affected the arginine and proline metabolism pathways, of which ornithine levels were downregulated after BBR administration. Intragastric administration of M.intestinale and its metabolite ornithine to BBR-treated mice achieved a recovery of sperm concentration and testosterone levels. RNA sequencing of testes showed the genes related to the LDLR-mediated cholesterol-synthesis testosterone pathway were downregulated after BBR administration. The levels of testosterone increased and Ldlr gene became more transcriptionally active in TM3 cells cultured in media supplemented with ornithine. This study for the first time revealed an association between BBR-induced gut Muribaculaceae dysbiosis and defects in spermatogenesis via ornithine metabolism, which provided a candidate and strategy for the treatment of infertility caused by a decreased serum testosterone level-induced by gut microbiota dysbiosis.

pharmacology and toxicology↗