Recent studies have shown that shorter periods of ejaculatory abstinence may enhance certain sperm parameters, but the molecular mechanisms underlying these improvements are still unclear. This study explored whether reduced abstinence periods could improve semen quality, particularly for use in assisted reproductive technologies (ART). We analyzed semen samples from men with normal sperm counts ( n = 101) and those with low sperm motility or concentration ( n = 53) after 3-7 days of abstinence and then after 1-3 h of abstinence, obtained from the Reproductive & Genetic Hospital of CITIC-Xiangya (Changsha, China). Physiological and biochemical sperm parameters were evaluated, and the dynamics of transfer RNA (tRNA)-derived fragments (tRFs) were analyzed using deep RNA sequencing in five consecutive samples from men with normal sperm counts. Our results revealed significant improvement in sperm motility and a decrease in the DNA fragmentation index after the 1- to 3-h abstinence period. Additionally, we identified 245 differentially expressed tRFs, and the mitogen-activated protein kinase (MAPK) signaling pathway was the most enriched. Further investigations showed significant changes in tRF-Lys-TTT and its target gene mitogen-activated protein kinase kinase 2 ( MAP2K2 ), which indicates a role of tRFs in improving sperm function. These findings provide new insights into how shorter abstinence periods influence sperm quality and suggest that tRFs may serve as biomarkers for male fertility. This research highlights the potential for optimizing ART protocols and improving reproductive outcomes through molecular approaches that target sperm function.
Male ; Humans ; Spermatozoa/metabolism* ; RNA, Transfer/genetics* ; Sperm Motility/genetics* ; Adult ; Semen Analysis ; Sexual Abstinence/physiology* ; Sperm Count ; DNA Fragmentation

The aryl hydrocarbon receptor (AhR) plays a crucial role in regulating many physiological processes. Activating the AhR-CYP1A1 axis has emerged as a novel therapeutic strategy against various inflammatory diseases. Here, a practical in situ cell-based fluorometric assay was constructed to screen AhR-CYP1A1 axis modulators, via functional sensing of CYP1A1 activities in live cells. Firstly, a cell-permeable, isoform-specific enzyme-activable fluorogenic substrate for CYP1A1 was rationally constructed for in-situ visualizing the dynamic changes of CYP1A1 function in living systems, which was subsequently used for discovering the efficacious modulators of the AhR-CYP1A1 axis. Following screening of a compound library, LAC-7 was identified as an efficacious activator of the AhR-CYP1A1 axis, which dose-dependently up-regulated the expression levels of both CYP1A1 and AhR in multiple cell lines. LAC-7 also suppressed macrophage M1 polarization and reduced the levels of inflammatory factors in LPS-induced bone marrow-derived macrophages. Animal tests showed that LAC-7 could significantly mitigate DSS-induced ulcerative colitis and LPS-induced acute lung injury in mice, and markedly reduced the levels of multiple inflammatory factors. Collectively, an optimized fluorometric cell-based assay was devised for in situ functional imaging of CYP1A1 activities in living systems, which strongly facilitated the discovery of efficacious modulators of the AhR-CYP1A1 axis as novel anti-inflammatory agents.

Despite therapy with potent antiviral agents, chronic hepatitis B (CHB) patients remain at high risk of hepatocellular carcinoma (HCC). While metabolites have been rediscovered as active drivers of biological processes including carcinogenesis, the specific metabolites modulating HCC risk in CHB patients are largely unknown. Here, we demonstrate that baseline plasma from CHB patients who later developed HCC during follow-up exhibits growth-promoting properties in a case-control design nested within a large-scale, prospective cohort. Metabolomics analysis reveals a reduction in long-chain acylcarnitines (LCACs) in the baseline plasma of patients with HCC development. LCACs preferentially inhibit the proliferation of HCC cells in vitro at a physiological concentration and prevent the occurrence of HCC in vivo without hepatorenal toxicity. Uptake and metabolism of circulating LCACs increase the intracellular level of acetyl coenzyme A, which upregulates histone H3 Lys14 acetylation at the promoter region of KLF6 gene and thereby activates KLF6/p21 pathway. Indeed, blocking LCAC metabolism attenuates the difference in KLF6/p21 expression induced by baseline plasma of HCC/non-HCC patients. The deficiency of circulating LCACs represents a driver of HCC in CHB patients with viral control. These insights provide a promising direction for developing therapeutic strategies to reduce HCC risk further in the antiviral era.

Notum, a negative feedback regulator of the Wnt signaling, has emerged as a promising target for treating glucocorticoid-induced osteoporosis (GIOP). This study showcases an efficient strategy for discovering the anti-Notum constituents from herbal medicines (HMs) as novel anti-GIOP agents. Firstly, a rapid-responding near-infrared fluorogenic substrate for Notum was rationally engineered for high-throughput identifying the anti-Notum HMs. The results showed that Bu-Gu-Zhi (BGZ), a known anti-osteoporosis herb, potently inhibited Notum in a competitive-inhibition manner. To uncover the key anti-Notum constituents in BGZ, an efficient strategy was adapted via integrating biochemical, phytochemical, computational, and pharmacological assays. Among all identified BGZ constituents, three furanocoumarins were validated as strong Notum inhibitors, while 5-methoxypsoralen (5-MP) showed the most potent anti-Notum activity and favorable safety profiles. Mechanistically, 5-MP acted as a competitive inhibitor of Notum via creating strong hydrophobic interactions with Trp128 and Phe268 in the catalytic cavity of Notum. Cellular assays showed that 5-MP remarkably promoted osteoblast differentiation and activated Wnt signaling in dexamethasone (DXMS)-challenged MC3T3-E1 osteoblasts. In dexamethasone-induced osteoporotic mice, 5-MP strongly elevated bone mineral density (BMD) and improved cancellous and cortical bone thickness. Collectively, this study constructs a high-efficient platform for discovering key anti-Notum constituents from HMs, while 5-MP emerges as a promising anti-GIOP agent.

Human carboxylesterase 2A (hCES2A) plays pivotal roles in prodrug activation and hydrolytic metabolism of ester-bearing chemicals. Targeted inhibition of intestinal hCES2A represents a feasible strategy to mitigate irinotecan-triggered gut toxicity (ITGT), but the orally active, selective, and efficacious hCES2A inhibitors are rarely reported. Here, a novel drug-like hCES2A inhibitor was developed via three rounds of structure-based drug design (SBDD) and structural optimization. Initially, donepezil was identified as a moderate hCES2A inhibitor from 2000 US Food and Drug Administration (FDA)-approved drugs. Following two rounds of SBDD and structural optimization, a donepezil derivative (B7) was identified as a strong reversible hCES2A inhibitor. Subsequently, nine B7 carbamates were rationally designed, synthesized and biologically assayed. Among all synthesized carbamates, C3 showed the most potent time-dependent inhibition on hCES2A (IC₅₀ = 0.56 nmol/L), excellent specificity and favorable drug-like properties. C3 could covalently modify the catalytic serine of hCES2A with high selectivity, while this agent also showed favorable safety profiles, high intestinal exposure, and impressive effects for ameliorating ITGT in both human intestinal organoids and tumor-bearing mice. Collectively, this study showcases a rational strategy for developing drug-like and serine-targeting covalent inhibitors against target serine hydrolase(s), while C3 emerges as a promising orally active drug candidate for ameliorating ITGT.

Hypoxic injury (HI) in the prenatal period often causes neonatal neurological disabilities. Due to the difficulty in obtaining clinical samples, the molecular and cellular mechanisms remain unclear. Here we use vascularized cerebral organoids to investigate the hypoxic injury phenotype and explore the intercellular interactions between vascular and neural tissues under hypoxic conditions. Our results indicate that fused vascularized cerebral organoids exhibit broader hypoxic responses and larger decreases in panels of neural development-related genes when exposed to low oxygen levels compared to single cerebral organoids. Interestingly, vessels also exhibit neural protective effects on T-box brain protein 2⁺ intermediate progenitors (IPs), which are markedly lost in HI cerebral organoids. Furthermore, we identify the role of bone morphogenic protein signaling in protecting IPs. Thus, this study has established an in vitro organoid system that can be used to study the contribution of vessels to brain injury under hypoxic conditions and provides a strategy for the identification of intervention targets.
Organoids/pathology* ; Animals ; Mice ; Hypoxia, Brain/metabolism* ; Brain/blood supply* ; Neurons/metabolism*

Non-coding RNAs(ncRNAs),encompassing microRNAs(miRNAs),long non-coding RNAs(lncRNAs),and circular RNAs(circRNAs),have emerged as critical regulators of gene expression and cellular function.In alcohol-associated liver disease(ALD),chronic alcohol consumption disrupts the expression and function of ncRNAs in the liver and circulation,contributing to the disease's pathogenesis and progression.Dysregulated ncRNAs influence key pathways involved in hepatocyte injury,lipid metabolism,inflam-mation,and hepatic stellate cell(HSC)activation,thereby exacerbating steatosis,inflammation,and fibrosis.Furthermore,extracellular vesicles play a pivotal role in mediating ncRNA-driven intercellular communication,amplifying liver damage and fibrosis.This review provides a comprehensive overview of the multifaceted roles of ncRNAs in ALD,with a focus on their mechanistic contributions to disease development and progression.Additionally,we discuss the potential of ncRNAs as diagnostic biomarkers and therapeutic targets,emphasizing their translational relevance in addressing the burden of ALD.

OBJECTIVE: To analyze the correlation between variants in the start codon of the α-globin gene and phenotypes of thalassemia, so as to provide a basis for the diagnosis and prevention of α-thalassemia. METHODS: A retrospective study was conducted on 7 patients diagnosed by Yangjiang People's Hospital and Guangzhou Hybribio Co. Ltd., from June 2019 to October 2022. Routine blood tests and hemoglobin electrophoresis were carried out. Potential variants were identified through polymerase chain reaction (PCR) combined with Reverse dot blotting (RDB), Gap-PCR, and Sanger sequencing. This study has been approved by the Medical Ethics Committee of People's Hospital of Yangjiang (Ethics No: 20240001). RESULTS: For the 7 patients, results of blood routine test of one case was unknown, and that of another was normal. The remaining 5 cases had presented with microcytic hypochromic anemia. The results of hemoglobin electrophoresis showed that one case had normal Hb A and slightly lower Hb A2, whilst another had significantly decreased Hb A and Hb A2, in addition with the appearance of a Hb H band. The content of Hb Bart's in four neonates was ≥ 0.4%. The remaining one case had no result. Genetic testing has identified 4 rare start codon mutations, namely HBA2: c.2delT, HBA2: c.1A>G, HBA2: c.1A>T, and HBA1: c.2T>C. Among these, Patient 1 had harbored compound heterozygous variants of HBA2: c.427T>C (Hb CS) and HBA2: c.2delT. Patient 4 had harbored compound heterozygous variants of HBA2: c.1A>G and Southeast Asian type deletion. CONCLUSION Heterozygotes with HBA start codon variants usually present as silent or mild thalassemia, and the symptoms of anemia may deteriorate when combined with other α-thalassemia variant. The HBA2: c.1A>T start codon variant was unreported previously in China. The detection of start codon variants has helped to clarify the causes of anemia, genetic counseling, and guidance for reproduction.
Humans ; Phenotype ; Codon, Initiator/genetics* ; Female ; Male ; Retrospective Studies ; alpha-Globins/genetics* ; alpha-Thalassemia/genetics* ; Hemoglobin A/genetics* ; Adult ; Mutation

Objective:To analyze the association between air pollution, genetic susceptibility, and the risk of all-cause mortality and cardiovascular outcomes in patients with atrial fibrillation (AF).Methods:AF patients aged between 40-69 years old registered in the United Kingdom Biobank from 2006 to 2010 were included. After excluding those lost to follow-up or with incomplete data during follow-up, 5 814 subjects were analyzed. Long-term exposure to air pollution was estimated at the geocoded residential address of each participant. Genetic risk scores for all-cause mortality, cardiovascular disease, heart failure, myocardial infarction, and stroke were constructed separately for each object to assess the corresponding genetic susceptibility. The Cox proportional hazards model was used to analyze the association between air pollution, genetic susceptibility, and the risk of all-cause mortality and cardiovascular outcomes in AF patients.Results:During a median follow-up of 12.4 years, there were 929 of all-cause mortality (15.98%) and 1 772 of cardiovascular events (30.48%). Multivariable-adjusted analyses revealed that higher exposure to PM 2.5, PM 10, NO x, and NO 2 was associated with an increased risk of cardiovascular disease mortality, heart failure, myocardial infarction, and stroke, with hazard ratios ( HRs) ranging from 1.26 to 1.48. Specifically, for each interquartile range ( IQR) increase in PM 2.5 exposure, the HRs for the outcomes mentioned above were 1.33 (95% CI: 1.14-1.54), 1.42 (95% CI: 1.31-1.54), 1.46 (95% CI: 1.30-1.64), and 1.43 (95% CI: 1.27-1.61), respectively. Both NO x and NO 2 exposures were associated with a 9% increased risk of all-cause mortality per IQR increment, with corresponding HRs of 1.09 (95% CI: 1.02-1.17) and 1.09 (95% CI: 1.01-1.17), respectively. Individuals with high genetic susceptibility to AF had a higher risk of myocardial infarction and stroke compared to those with low genetic susceptibility, with corresponding HRs of 1.39 (95% CI: 1.04-1.87) and 1.46 (95% CI: 1.09-1.95), respectively. Compared to AF patients with low air pollution exposure, those with high air pollution exposure have adjusted population attributable fractions of up to 33.57% (95% CI: 17.87%-46.26%) for cardiovascular mortality, 28.61% (95% CI: 20.67%-35.75%) for heart failure, 33.35% (95% CI: 20.97%-43.79%) for myocardial infarction, and 42.29% (95% CI: 30.05%-52.71%) for stroke. Furthermore, there was an additive interaction between PM 2.5, NO x, and NO 2 exposure and high genetic susceptibility on the incidence of myocardial infarction. An additive interaction was also observed between NO x, NO 2 exposure, and high genetic susceptibility on the incidence of heart failure (all P<0.05). Conclusions:Both air pollution and genetic susceptibility increase the risk of all-cause mortality and cardiovascular outcomes in AF patients.