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*

Objective To investigate the effects and underlying mechanisms of total flavonoids of sarcandra glabra(TFFSG)on bone marrow mesenchymal stem cells(BMSCs)and their derived exosomes in immune thrombo-cytopenia(ITP),with a focus on promoting megakaryocyte differentiation and maturation.Methods BMSCs induced by rabbit anti-rat platelet serum(APS)were divided into five groups:a blank control group,an ITP-BMSCs model group,and three TFFSG intervention groups with low(1.95 μg/mL),medium(3.90 μg/mL),and high doses(7.80 μg/mL).The apoptosis rates and the expression levels of apoptosis-related proteins-B-cell lymphoma 2(Bcl-2),Bcl-2-associated X protein(BAX),and Cysteinyl aspartate-specific proteinase-3(Caspase-3)-were assessed.Exosomes were isolated from the blank control group(NC-BMSCs-Exos),the ITP-BMSCs model group(ITP-BMSCs-Exos),and the medium-dose TFFSG group(TFFSG-BMSCs-Exos).Each group's exosomes(5 μg/mL)were co-cultured with megakaryocytic lineage Dami cells for 96 hours.Flow cytometry was employed to evaluate the expression of megakaryocytic differentiation markers(CD41a,CD42b,CD61)and the proportion of polyploid cells(≥4 N)in each group.Western Blot analysis was conducted to examine the expression of p-MEK1/2,MEK1/2,p-ERK1/2,and ERK1/2 across all groups.Results Compared with the ITP-BMSCs model group,the apoptosis rates in all TFFSG intervention groups were significantly reduced(P<0.01).In the medium-and high-dose TFFSG groups,BAX and Caspase-3 expression levels were markedly downregulated,whereas Bcl-2 expression was upregulated(P<0.05,P<0.01).Compared with the ITP-BMSCs-Exos group,the TFFSG-BMSCs-Exos group demonstrated increased expression of CD41a+,CD42b+,and CD61+,a higher proportion of polyploid cells(≥4 N)(P<0.05),as well as elevated ratios of p-MEK1/2 to MEK1/2 and p-ERK1/2 to ERK1/2(P<0.05).Conclusion TFFSG inhibits apopto-sis of ITP-state BMSCs in vitro and promotes megakaryocyte differentiation and polyploidization maturation through BMSC-derived exosomes by activating the MEK1/2-ERK1/2 signaling pathway.

Objective To develop a deep learning model based on fundus retinal images to improve the detection rate of mild cognitive impairment(MCI)in patients with coronary heart disease,achieve early intervention and improve prognosis.Methods The study was a single-center cross-sectional study that retrospectively included patients diagnosed with coronary heart disease(CHD)by coronary angiography(≥50％ stenosis of at least one coronary vessel)from Beijing Anzhen Hospital between November 2021 and December 2022.The whole data set was randomly divided into the training set and the testing set according to the ratio of 8∶2 for model development.After that,the patient data of the same center from January 2023 to April 2023 were included in the time verification method to verify the model.The diagnostic criteria for MCI were MMSE＜27 or MoCA＜26.Four kinds of convolutional neural network(CNN)architectures were used to train fundus images,and a comprehensive vision model of MCI detection was established through model integration.The area under the curve(AUC),sensitivity and specificity of the receiver operating curve(ROC)were used to evaluate the performance of the AI model.Results We collected 5 880 eligible fundus images from 3 368 CHD patients.Based on the results of the MMSE scale,the algorithm was labeled,including 2 898 males and 527 MCI patients.The AUC of the deep learning model in the test group is 0.733(95％CI 0.688-0.778),and the sensitivity of the algorithm in the test group is 0.577(95％CI 0.528-0.625)by using the operating point with the maximum sum of sensitivity and specificity.With a specificity of 0.758(95％CI 0.714-0.802),corresponding to a validated AUC of 0.710(95％CI 0.601-0.818).Based on the results of the MoCA scale,the algorithm labels 2 437 males and 1 626 MCI patients.The AUC of the deep learning model in the test group was 0.702(95％CI 0.671-0.733).The operating point with the maximum sum of sensitivity and specificity was selected,and the sensitivity of the algorithm was 0.749(95％CI 0.719-0.778)and the specificity was 0.561(95％CI 0.527-0.595),corresponding to the AUC value of the verification group was 0.674(95％CI 0.622-0.726).Conclusions The deep learning algorithm model based on fundus images has good diagnostic performance,and may be used as a new non-invasive,convenient and rapid screening method for MCI in CHD population.

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 A 2, whilst another had significantly decreased Hb A and Hb A 2, 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.

Objective To investigate the association between intraoperative dexamethasone administration and long-term survival outcomes.Methods A total of 1 629 NSCLC patients who underwent lung tumor resection between January 2008 and December 2014 were included in this study.A propensity score-matched cohort was generated at a ratio of 1∶2 to compare patients who received dexamethasone with those who did not.This matching process resulted in a cohort of 532 patients in the non-DEX group and 283 patients in the DEX group.Within this propensity score-matched cohort,disease-free survival(DFS)and overall survival(OS)were compared between the non-DEX and DEX groups using the Kaplan-Meier method.Additionally,Cox proportional hazards regression analysis was used to evaluate the associations between intraoperative administration of dexamethasone and high-risk factors for postoperative nausea and vomiting(PONV),as well as their impact on DFS and OS.Results After propensity score matching,intraoperative dexamethasone was significantly associated with worse OS(P=0.005),while no significant correlation was observed between intraoperative dexamethasone and DFS.Multivariate Cox regression analyses indicated that intraoperative dexamethasone was associated with poorer overall survival(HR=1.233,95%CI:1.002～1.516,P=0.048).In subgroup analyses,intraoperative dexamethasone was significantly associated with shorter OS in the female,video-assisted thoracoscopic surgery(VATS),prolonged anesthetic time,and inhalation anesthesia subgroups.Conclusions There was a significant correlation between intraopera-tive dexamethasone administration and overall survival in NSCLC patients following curative surgery.In high-risk subgroups for PONV,including females,those undergoing VATS,patients with prolonged anesthetic duration,and those under inhalation anesthesia,the administration of intraoperative dexamethasone was associated with a potentially poorer prognosis compared to patients who did not receive intraoperative dexamethasone.