Xihe Li

Post-weaning diarrhea is a prevalent gastrointestinal disorder in intensive dairy calf production, causing impaired growth, elevated mortality and widespread excessive antimicrobial use. While fecal microbiota dysbiosis is well implicated in diarrhea pathogenesis, specific microbial signatures linked to post-weaning diarrhea remain incompletely defined. In this case–control study, we performed 16S rRNA gene amplicon sequencing to characterize and compare fecal microbiota of 101 diarrheic and 101 clinically healthy female Holstein calves at 7 days post-weaning. Diarrheic calves exhibited significantly higher species richness (Chao1 index, p = 8.7 × 10⁻²¹) but reduced community evenness (Simpson index, p = 2.3 × 10⁻¹⁰), a distinct pattern from most neonatal calf diarrhea reports. Microbial community structure differed significantly between groups (PERMANOVA, Bray–Curtis dissimilarity, R² = 0.084, p = 0.001). Four genera including Faecousia (fold change = 1.40) were enriched in diarrheic calves, while six genera including Duncaniella (fold change = 0.34) were depleted after FDR correction and validated by complementary statistical methods. PICRUSt2 functional prediction revealed downregulated carbohydrate metabolism and energy biosynthesis pathways in diarrheic calves, alongside upregulated xenobiotic degradation and stress response pathways. This study identifies high-confidence bacterial biomarkers for post-weaning calf diarrhea, providing a solid microbial basis for developing targeted microbiota-based prevention and intervention strategies.

Ovum pick-up (OPU) enables high-frequency oocyte retrieval from selected dairy cow donors, facilitating favorable genetic progression. However, oocytes obtained via OPU and subjected to in vitro maturation frequently suffer from severe oxidative stress, mitochondrial dysfunction, and DNA damage, resulting in lower pregnancy rates compared to those of in vivo-derived embryos. Melatonin (MT), as a potent antioxidant, may exert beneficial effects on these OPU-retrieved oocytes. In the current study, by combining in vitro and in vivo experiments, the protective effects and potential molecular mechanisms of MT on disrupted oocyte quality and development caused by OPU were systemically investigated. By integrating oocyte quality assessment, follicular fluid metabolomics, and blastocyst transcriptomics, the results showed that subcutaneous administration of MT to cows prior to OPU significantly increased the number of high-quality Grade A oocytes and reduced the number of low-quality Grade D oocytes compared to the control. These improvements were accompanied by reduced local and systemic oxidative stress, enhanced glutathione metabolism, and lower serum progesterone concentrations at the measured time points, coinciding with a more favorable endocrine environment for follicular development. The results from untargeted metabolomics of the follicular fluid revealed that MT supplementation was associated with an altered follicular fluid microenvironment characterized by the upregulation of estrogen derivatives and glutathione-related pathways. Transcriptomic analysis of blastocysts showed significant upregulation of the rate-limiting genes steroidogenic acute regulatory protein (STAR) and 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR), suggesting a potential role in promoting the synthesis of reproductive hormones and maintaining the progress of embryo development. The in vitro study showed that MT supplementation at a concentration of 10⁻⁷ mol/L in oocyte maturation media significantly improved cleavage rates, blastocyst rates, and total blastocyst cell numbers compared to the control. In vitro evaluations demonstrated that MT scavenged intracellular reactive oxygen species (ROS), while transcriptomic analysis indicated a reprogramming of the embryonic transcriptome. These transcriptomic changes were associated with the AMPK, FoxO, and autophagy pathways, as well as the modulation of endoplasmic reticulum stress and cellular senescence. The results from both the in vivo and in vitro studies suggested that MT supplementation was associated with a follicular microenvironment favorable for oocyte growth and protected embryos from oxidative damage. Therefore, MT supplementation effectively reduced the disrupted oocyte development caused by OPU and improved oocyte recovery and quality in general. These findings provide promising experimental evidence for the potential application of MT in dairy breeding and offer insights into the associated molecular pathways. However, further functional validation is required to fully elucidate the underlying mechanisms and establish its large-scale applicability.

Background/Objectives: Alcohol-associated liver disease (ALD) is driven by gut-liver axis dysfunction, including intestinal barrier disruption, dysbiosis, microbial translocation, inflammation, metabolic dysfunction, and malnutrition. Fermented dairy foods may modulate several of these domains, yet whether sheep yogurt, as an intact fermented dairy matrix, is relevant in ALD is unknown. This scoping review mapped evidence relevant to sheep yogurt, ALD, and gut-liver axis biology. Methods: A PRISMA-ScR-guided scoping review searched PubMed/MEDLINE, Web of Science, Scopus, and Google Scholar from January 2006 to February 2026. Eligible sources were charted using a prespecified framework classifying evidence as direct, indirect, or mechanistic inference. Mapped domains included ALD pathophysiology; intestinal barrier integrity; bacterial and fungal microbial ecology; bile acid and tryptophan-aryl hydrocarbon receptor signaling; nutritional vulnerability; fermented dairy interventions; and ovine dairy-matrix characteristics. Results: Of 1388 records identified, 121 sources were included after duplication and screening. No eligible study directly tested sheep yogurt or a defined sheep yogurt preparation in ALD-relevant experimental or clinical settings. Indirect evidence supported the relevance of gut-liver axis dysfunction to ALD and indicated that selected fermented dairy products, probiotics, postbiotics, and microbial preparations may influence intestinal permeability, inflammatory signaling, microbial ecology, oxidative stress, and liver-injury outcomes. Compositional data supported sheep yogurt as a distinct food matrix. However, findings from isolated components, probiotic-only interventions, and non-ALD models could not be interpreted as evidence of sheep yogurt efficacy in ALD. Conclusions: The current literature supports a hypothesis-driven research framework rather than any therapeutic claim for sheep yogurt in ALD. Any potential benefit of sheep yogurt in ALD remains hypothetical and cannot support clinical or dietary recommendations until validated experimentally. Future direct, comparator-controlled studies of intact sheep yogurt should assess liver injury, barrier integrity, microbial translocation, relevant metabolites, and nutrition-related outcomes.

The mammalian early embryo possesses totipotency and can be captured as extended pluripotent stem cells (EPSCs). The first two cell differentiations result in epiblast, primitive endoderm, and trophectoderm, with the trilineage coexisting in a unified uterine microenvironment. Nevertheless, the in vitro counterparts—primed PSCs, trophoblast stem cells (TSCs), and extraembryonic endoderm (XEN) cells—require a distinct culture system. In this study, we successfully derived stable porcine EPSCs from fibroblasts at 35% efficiency, and interestingly observed that these EPSCs differentiated in parallel and gave rise to the transient coexistence (36–84 h) of trilineage cells when cultured in a single system (LCDM: hLIF, CHIR99021, DiM, and MiH). Then, XEN cells gradually predominated and eventually became the sole population in prolonged LCDM culture. However, TSCs and primed PSCs had to be differentiated from EPSCs under their respective culture system. EPSCs can differentiate into PGC-like cells independently of genetic modification and contribute to mouse neurula-stage embryos. Collectively, the trilineage coexistence phenomenon may provide novel insight into an early embryogenesis mechanism and strategy for porcine blastoid construction.

The Six1 ( SIX homeobox 1) gene is pivotal in renal and pulmonary development and differentiation. Its dysregulation is implicated in oncogenesis and tumor progression via enhancing cell proliferation and delaying senescence. However, whether or how it functions in the natural aging have not been investigated. To answer this question, we generated Six1 gene knockout mice using CRISPR-Cas9 technology. All Six1 biallelic knockout mice died at birth since the underdeveloped lungs. In Six1 ^+/– mice, the developmental deficiencies in kidneys with vacuolar degeneration and epithelial disruption in renal tubules, as well as hematopoietic interstitial infiltration and lungs with interstitial condensation and alveolar hypoplasia were observed. These developmental deficiencies persist with age and age-dependent phenotypes become more pronounced in Six1 ^+/– mice compared to the wild-type, with upregulation of senescence markers (p16, p53) and senescence-associated secreted factors (e.g., TNF-α, TIMP-2), increased α-SMA expression and collagen deposition, as well as susceptibility to pulmonary fibrosis. Transcriptomic sequencing coupled with bioinformatics analysis indicated that genes with altered expression in Six1 ^+/– mouse lungs showed enrichment in pathways associated with senescence, including the NF-κB and TNF signaling pathways. These transcriptional patterns were also associated with gene sets involved in mitochondrial metabolic processes. Collectively, these findings suggest that Six1 haploinsufficiency is associated with transcriptional signatures linked to aging-related pathways under physiological conditions in mice, providing potential clues for future studies exploring mechanisms of aging.

A minority of 8C-like cells (8CLCs) expressing zygotic genome activation genes are captured in naïve embryonic stem cells (ESCs). However, how human ESCs transition into 8CLCs remains unknown. Here, we show that NELFA is dispensable in human primed ESCs but critical for naïve pluripotency, and its overexpression promotes the primed-to-naïve conversion. Notably, NELFA robustly induces 8CLCs that express human ZGA-specific genes in naïve ESCs. NELFA-induced human 8CLCs can contribute to both embryonic and extraembryonic developmental potential in the interspecies human-mouse chimera assay. Importantly, we also discovered that TP53 can activate the human 8CLCs state, and NELFA might be an upstream regulator of TP53. Furthermore, TP53 and NELFA are both essential for the complete transition to the 8CLC state. We also demonstrate that sustained NELFA overexpression in primed ESCs directs neural lineage specification. Thus, NELFA establishes and maintains naïve pluripotency and drives the 8CLC state, providing insights into early human embryogenesis.

Intake of plant polysaccharides are associated with a reduced risk of ulcerative colitis (UC). Eucommia polysaccharides (EUPs) are promising nutritional supplements with notable antibacterial, anticancer, and anti-inflammatory properties. They exhibit a moderate molecular weight and are resistant to gastric acid degradation. Yet, the action mechanisms of microorganisms and metabolites in EUPs for UC treatment remain incompletely elucidated. The current study was formulated to assess the therapeutic efficacy of EUPs against fecal microbiota transplantation (FMT)-induced colitis, focusing on comparing the effects of low-dose and high-dose EUPs. After East Frisian sheep received dextran sulfate sodium (DSS) intervention, their fecal microbiota was used to prepare fecal bacterial suspensions for mouse FMT. Administration of high-dose EUPs alleviated key colitis symptoms, improved colonic epithelial barrier, preserved microbial diversity, and significantly reduced harmful bacterial (e.g., g_Klebsiella and g_unidentified_Enterobacteriaceae ). Furthermore, this treatment significantly enriched the bile secretion pathways, particularly those involving deoxycholic acid (DCA) and hyodeoxycholic acid (HDCA). Additionally, DCA and HDCA were significantly negatively correlated with g_unidentified_Enterobacteriaceae and g_Klebsiella , and these two bile acids were also negatively correlated with key genes associated with the IL-17 signaling pathway. Overall, this study elucidates that EUPs ameliorate FMT-induced colitis in a mouse model via restoring gut microbes and metabolites and modulating the IL-17 pathway, thereby providing novel insights into therapeutic strategies for UC.

Efficient derivation of neural stem cells (NSCs) from human pluripotent stem cells (PSCs) is crucial in regenerative medicine. Here, we report that the combined application of the retinoic acid receptor agonist TTNPB and the GSK3β inhibitor CHIR99021 in a chemically defined medium enabled the induction of a highly advanced NSCs (ANSCs) population from PSCs. ANSCs display robust neuroectodermal gene expression and a heightened capacity for neural lineage commitment. The combination of TTNPB and CHIR99021 markedly enhanced global chromatin accessibility, particularly at neuroectoderm‐specific regulatory elements such as PAX6 and SOX1 , in parallel with reduced accessibility at the loci of pluripotency factors. Notably, TTNPB alone also exerts a marked effect in enhancing chromatin accessibility. Untargeted metabolomic analysis identified a distinct neural‐ectoderm associated metabolic state in ANSCs, prominently characterized by elevated choline, alongside S‐(5′‐adenosyl)‐L‐homocysteine, adenosine 5′‐diphosphate, and glutathione. Exogenous addition of these metabolites was sufficient to induce neuroectodermal marker expression, highlighting the instructive role of the metabolic network in neural fate induction. Moreover, functional studies showed that ANSCs enabled engraftment into depressed rat hippocampi and restored depression‐like behavioral deficits. Our study presents a novel small‐molecule strategy that leverages TTNPB‐centered epigenetic remodeling and metabolic reprogramming as dual mechanisms driving neural differentiation.