Inter- and trans-generational impacts of real-world PM2.5 exposure on male-specific primary hypogonadism

Exposure to PM2.5, a harmful type of air pollution, has been associated with compromised male reproductive health; however, it remains unclear whether such exposure can elicit transgenerational effects on male fertility. Here, we aim to examine the effect of paternal exposure to real-world PM2.5 on the reproductive health of male offspring. We have observed that paternal exposure to real-world PM2.5 can lead to transgenerational primary hypogonadism in a sex-selective manner, and we have also confirmed this phenotype by using an external model. Mechanically, we have identified small RNAs (sRNAs) that play a critical role in mediating these transgenerational effects. Specifically, miR6240 and piR016061, which are present in F0 PM sperm, regulate intergenerational transmission by targeting Lhcgr and Nsd1, respectively. We have also uncovered that piR033435 and piR006695 indirectly regulate F1 PM sperm methylation by binding to the 3'-untranslated region of Tet1 mRNA. The reduced expression of Tet1 resulted in hypermethylation of several testosterone synthesis genes, including Lhcgr and Gnas, impaired Leydig cell function and ultimately led to transgenerational primary hypogonadism. Our findings provide insights into the mechanisms underlying the transgenerational effects of paternal PM2.5 exposure on reproductive health, highlighting the crucial role played by sRNAs in mediating these effects. The findings underscore the significance of paternal pre-conception interventions in alleviating the adverse effects of environmental pollutants on reproductive health.

Perturbation of IP3R-dependent endoplasmic reticulum calcium homeostasis by PPARδ-activated metabolic stress leads to mouse spermatocyte apoptosis: A direct mechanism for perfluorooctane sulfonic acid-induced spermatogenic disorders

Perfluorooctane sulfonic acid (PFOS) as an archetypal representative of per- and polyfluoroalkyl substances (PFAS) is ubiquitously distributed in the environment and extensively detected in human bodies. Although accumulating evidence is suggestive of the deleterious effects of PFOS on male reproduction, the direct toxicity of PFOS towards spermatogenic cells and the relevant mechanisms remain poorly understood. The aims of the present study were to explore the direct effects and underlying molecular mechanisms of PFOS on spermatogenesis. Through integrating animal study, transcriptome profiling, in silico toxicological approaches, and in vitro validation study, we identified the molecular initiating event and key events contributing to PFOS-induced spermatogenic impairments. The mouse experiments revealed that spermatocytes were involved in PFOS-induced spermatogenic disorders and the activation of peroxisome proliferator-activated receptor delta (PPARδ) was linked to spermatocyte loss in PFOS-administrated mice. GC-2spd(ts) cells were treated with an increased gradient of PFOS, which was relevant to environmental and occupational exposure levels of PFOS in populations. Following 72-h treatment, cells was harvested for RNA sequencing. The transcriptome profiling and benchmark dose (BMD) modeling identified endoplasmic reticulum (ER) stress as the key event for PFOS-mediated spermatocyte apoptosis and determined the point-of-departure (PoD) for perturbations of ER stress signaling. Based on the calculated PoD value, further bioinformatics analyses combined with in vitro and in vivo validations showed that PFOS caused metabolic stress by activating PPARδ in mouse spermatocytes, which was responsible for Beclin 1-involved inositol 1,4,5-trisphosphate receptor (IP3R) sensitization. The disruption of IP3R-mediated ER calcium homeostasis triggered ER calcium depletion, leading to ER stress and apoptosis in mouse spermatocytes exposed to PFOS. This study systematically investigated the direct impacts of PFOS on spermatogenesis and unveiled the relevant molecular mechanism of PFOS-induced spermatogenic disorders, providing novel insights and potential preventive/therapeutic targets for PFAS-associated male reproductive toxicity.

Effects and possible mechanisms of combined exposure to noise and carbon monoxide on male reproductive system in rats

Environmental hazards are an increasing concern due to the rapid pace of industrialization. Among these hazards, noise and carbon monoxide (CO) are common risk factors and have been shown to cause serious health problems. However, existing studies focused on the individual effects of noise and CO exposure and the combined effects of these two factors remain poorly understood. Our study aimed to examine the combined effects of noise and CO exposure on testicular function by constructing individual and combined exposure models. Our findings indicated that combined exposure to noise and CO was associated with a higher risk of testicular damage and male reproductive damage when compared to exposure alone. This was evidenced by poorer semen quality and more severe pathological damage to the testis. This combined exposure led to higher levels of oxidative stress and apoptosis in the testes, with bioinformatics analyses suggesting the signaling pathways involved in these responses. Specifically, activation of the P53 signaling pathway was found to contribute to the testicular damage caused by the combined exposure. Encouragingly, pterostilbene (PTE), a novel phytochemical, alleviated combined exposure-induced testicular damage by reducing oxidative stress and germ cell apoptosis. Overall, we identified joint reproductive toxicity resulting from the exposure to noise and CO, and found that PTE is a promising potential treatment for injuries caused by these factors. The cover image is based on the Research Article Effects and possible mechanisms of combined exposure to noise and carbon monoxide on male reproductive system in rats by Yingqing Li et al., https://doi.org/10.1002/tox.23927.

The value of ICG-guided left colon vascular variation and anatomical rules for the radical resection of proctosigmoid colon cancer

Objective

During laparoscopic radical resection for proctosigmoid colon cancer (PCC), surgeons could inadvertently damage the arteries when following the operation path.This study investigated the variations in left colon blood vessels in order to guide the scientific protection of the marginal artery (MA) during laparoscopic surgery for PCC.

Methods

Data from seven patients who underwent inferior mesenteric artery (IMA) angiography were included as imaging references to preliminarily explore the vascular structure and variation in the left colon. The clinical video data of 183 PCC patients were retrospectively analyzed to observe intraoperative MA injury. Meanwhile, a prospective cohort of 96 patients with the same disease underwent intraoperative indocyanine green (ICG) fluorescence imaging of the peripheral sigmoid artery network, the variation of marginal arteries was summarized, and the distance between vessels and the bowel was measured at different levels. Patients were divided into 'ICG group' and 'non-ICG group' according to whether ICG guidance was performed, and perioperative conditions were compared between the two groups. Taking the integrity of lymph node dissection into consideration, 18 patients underwent carbon nanonode tracing. This study was conducted under the standard consent and ethical approval of the Ethics Committee of our center.

Results

7 patients with IMA angiography shared some vascular structures, defined as 'Dangerous Triangle' and 'Secure Window'. Through intraoperative observation, the primary arch was typically located 4.2 (2.3-6.0) cm away from the intestinal canal, and 5.21% (5/96) patients had poor anastomosis at the primary arch. Moreover, secondary vascular arches (6.4 (4.6-10.0) cm from the intestinal wall) were observed in 38.54% of patients. MA injury was identified in 2 of 183 cases, and the ischemic bowel was timely dissected, whereas no such injury occurred during ICG fluorescenceguided surgery. Guided by carbon nanoparticles, the integrity of lymph node dissection can be maintained while preserving the secondary arch in all patients.

Conclusions

This study demonstrated the benefits of ICG guidance in protecting the intestinal blood supply in laparoscopic PCC surgery. By enhancing the understanding of primary and secondary vascular arches, secure windows, and dangerous triangles, surgeons can safely optimize the surgical path during surgery.

[Feasibility of a three-sided encapsulation procedure based on fascia anatomy in laparoscopic lateral lymph node dissection for middle and low rectal cancer]

Objective: To explore the feasibility and value of performing a three-sided encapsulation procedure based on fascia anatomy in laparoscopic lateral lymph node dissection (LLND) for middle and low rectal cancer. Methods: This was a retrospective review. The study cohort comprised patients who met the diagnostic criteria for rectal cancer according to the Chinese Guidelines for the Diagnosis and Treatment of Colorectal Cancer, had a short lymph node diameter of >5 mm on the lateral side within the 15 days before surgery, were evaluated as feasible candidates for laparoscopic total mesorectal excision+LLND surgery, had been diagnosed with low or intermediate level rectal cancer, and whose tumor was less than 8 cm away from the anal verge according to pathological examination of the operative specimen. Patients with a history of other malignant tumors of the abdomen or with incomplete follow-up data were excluded. Forty-two patients with middle and low rectal cancer who had undergone lateral lymph node dissection in diagnosis and treatment center of Gastrointestinal Cancer of Guangdong Hospital of Chinese Medicine from Jan.2018 to Dec.2022 were enrolled. There were 24 men (57.1%) and 18 women (42.9%) aged 58.4±11.8 years and the median BMI was 22.5 (19.3-24.1) kg/m2. The main point of the three-sided encapsulation procedure is to expand the external side medial to the external iliac artery and vein, narrowing the range of exterior side dissection. The anterior-medial side is designed to expand the vesical fascia to define the range of anterior-medial side extension. The internal side is fully extended to the ureterohypogastric nerve fascia; the distal point of the caudal extension reaches the level of the Alcock canal and the bottom reaches the piriformis, enabling dissection of the obturator nerve and No.283 lymph nodes. No.263D lymph nodes are dissected by exposing the internal iliac artery and its branches, dissecting the group No.263P lymph nodes, and severing the inferior vesical artery. Finally, the lateral lymphatic tissue is completely resected. Relevant variables were recorded, including the number of lateral lymph nodes detected, the rate of lymph node metastasis, operation duration, intraoperative blood loss, postoperative complications, postoperative hospital stay, and 3-year overall survival rate. Results: Laparoscopic surgery was successfully completed in all patients with no conversions to open surgery and no intraoperative complications. Twenty-seven (64.3%) of the study patients underwent left-sided LLND, 10 (23.8%) right-sided LLND, and five (11.9%) bilateral LLND, with lymph nodes cleared on both sides. All patients' lymph nodes were examined pathologically. A median of 17.0 (11.7, 26.0) lymph nodes was detected, the median of lateral lymph nodes being 5.0 (2.0, 10.2). The median operation time was 254.5 (199.0, 325.2) minutes. The median intra-operative blood loss was 50.0 (30.0, 100.0) mL. All patients were diagnosed with adenocarcinoma by pathological examination of the operative specimen. Two patients developed postoperative intestinal obstruction, one lymphatic leakage, and one a perineal incision infection. There were no cases of anastomotic leakage. The median postoperative hospital stay was 6.0 (5.0, 7.0) days and the median follow-up time 23.5 (9.0, 36.7) months. During follow-up, three patients (7.1%) died of tumor recurrence and metastasis. Two (4.8%) experienced mild urinary dysfunction, and one (2.4%) had moderate postoperative erectile dysfunction. One patient (2.4%) was found to have prostate and lung metastases 3 month after surgery. The 3-year overall survival rate was 74.4%. Conclusions: Three sided encapsulation is a safe and feasible procedure for LLND, achieving accurate and complete clearance of lateral lymphatic tissue.

TERT transcription and translocation into mitochondria regulate benzo[a]pyrene/BPDE-induced senescence and mitochondrial damage in mouse spermatocytes

Telomere and mitochondria may be the targets of Benzo[a]pyrene (BaP) -induced male reproductive damage, and further elucidation of the toxic molecular mechanisms is necessary. In this study, we used in vivo and in vitro exposure models to explore the molecular mechanisms of TERT regulation in BaP-induced telomere and mitochondrial damage in spermatocytes. The results showed that the treatment of benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide (BPDE), the active metabolite of BaP, caused telomere dysfunction in mouse spermatocyte-derived GC-2 cells, resulting in S-phase arrest and increased senescence-associated secretory phenotype (SASP). These effects were significantly alleviated by telomerase agonist (ABG) pretreatment in GC-2 cells. SIRT1, FOXO3a, or c-MYC overexpressing GC-2 cell models were established to demonstrate that BPDE inhibited TERT transcriptional expression through the SIRT1/FOXO3a/c-MYC pathway, leading to telomere dysfunction. We also observed that BPDE induced mitochondrial compromise, including complex I damage, accompanied by reduced mitochondrial TERT expression. Based on this, we constructed wild-type TERT-overexpressing (OE-TERTwt) and mitochondria targeting TERT-overexpressing (OE-TERTmst) GC-2 cell models and found that OE-TERTmst GC-2 cells improved mitochondrial function better than OE-TERTwt GC-2 cells. Finally, ICR mice were given BaP by intragastric administration for 35 days, which verified the results of the in vitro study. The results shown that BaP exposure can lead to spermatogenesis disturbance, which is related to the telomere and mitochondrial damage in spermatocytes. In conclusion, our results suggest that BPDE causes telomere and mitochondrial damage in spermatocytes by inhibiting TERT transcription and mitochondrial TERT expression. This study elucidates the molecular mechanism of male reproductive toxicity due to environmental pollutant BaP, and also provides a new perspective for the exploration of interventions and protective measures against male reproductive damage by BaP.

PPARα/ACOX1 as a novel target for hepatic lipid metabolism disorders induced by per- and polyfluoroalkyl substances: An integrated approach

BACKGROUND

Per- and polyfluoroalkyl substances (PFAS) are persistent and ubiquitous environmental contaminants with well-documented hepatotoxicity. However, the mechanistic linkage between PFAS exposure and non-alcoholic fatty liver disease (NAFLD) remains largely elusive.

OBJECTIVES

This study aimed to explore PFAS-to-NAFLD link and the relevant molecular mechanisms.

METHODS

The cross-sectional analyses using National Health and Nutrition Examination Survey (NHANES) data were conducted to investigate the association between PFAS exposure and NAFLD. A combination of in silico toxicological analyses, bioinformatics approaches, animal experiments, and in vitro assays was used to explore the molecular initiating events (MIEs) and key events (KEs) in PFAS-induced hepatic lipid metabolism disorders.

RESULTS

The cross-sectional analyses with NHANES data revealed the significant association between PFAS exposure and hepatic steatosis/NAFLD. The in silico toxicological analyses showed that PPARα activation induced by perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), prototypical representatives of PFAS, is the critical MIE associated with NAFLD-predominant liver diseases. Transcriptome-based bioinformatic annotation and analyses identified that transcriptional upregulation of hepatic acyl-CoA oxidase 1 (ACOX1) in PPARα-regulated peroxisomal β-oxidation pathway was the KE involved with PFOA/PFOS-perturbed hepatic lipid metabolic pathways in humans, mice and rats. The in vivo and in vitro assays further verified that ACOX1-mediated oxidative stress contributed to mitochondrial compromise and lipid accumulation in PFOA/PFOS-exposed mouse hepatocytes, which could be mitigated by co-treatment with ACOX1 inhibitor and mitochondria ROS scavenger. Additionally, we observed that besides PFOA and PFOS, hepatic ACOX1 exhibited good-fit response to short-term exposures of long-chain (C7-C10) perfluoroalkyl carboxylic acids (PFHpA, PFNA, PFDA) and perfluoroalkyl sulfonic acids (PFHpS, PFDS) in human hepatocyte spheroids through benchmark dose (BMD) modeling.

CONCLUSION

Our study unveils a novel molecular target for PFAS-induced hepatic lipid metabolic disorders, shedding new light on prediction, assessment, and mitigation of PFAS hepatotoxicity.

[Study on F9 gene expression downregulation and its clinical value in hepatocellular carcinoma]

Objective: To analyze the expression levels of the F9 gene and F9 protein in hepatocellular carcinoma by combining multiple gene chip data, real-time fluorescence quantitative PCR (RT qPCR), and immunohistochemistry. Additionally, explore their correlation with the occurrence and development of hepatocellular carcinoma, as well as with various clinical indicators and prognosis. Methods: The mRNA microarray dataset from the GEO database was analyzed to identify the F9 gene with significant expression differences associated with hepatocellular carcinoma. Liver cancer and adjacent tissues were collected from 18 cases of hepatocellular carcinoma. RT-qPCR method was used to detect the F9 gene expression level. Immunohistochemistry was used to detect the F9 protein level. Combined with the TCGA database information, the correlation between F9 gene expression level and prognostic and clinicopathological parameters was analyzed. The biological function of F9 co-expressed genes associated with hepatocellular carcinoma was analyzed by the Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG). Statistical analysis was performed using Graphpad Prism software. Results: Meta-analysis results showed that the expression of the F9 gene was lower in HCC tissues than in non-cancerous tissues. Immunohistochemistry results were basically consistent with those of RT-qPCR. The data obtained from TCGA showed that the F9 gene had lower expression values in stages III-IV, T3-T4, and patients with vascular invasion. A total of 127 genes were selected for bioinformatics analysis as co-expressed genes of F9, which were highly enriched in redox processes and metabolic pathways. Conclusion: This study validates that the F9 gene and F9 protein are lower in HCC. The down-regulation of the F9 gene predicts adverse outcomes, which may provide a new therapeutic target for HCC.

PM2.5 caused ferroptosis in spermatocyte via overloading iron and disrupting redox homeostasis

Fine particulate matter (PM_2.5) has been reported to cause various types of damage to male reproductive system, but the research on the underlying mechanisms is still insufficient. This study attempted to explore the underlying mechanisms of this widely concerning environmental health problem through in vivo and in vitro exposure models. Significant pathological damage and abnormal mitochondria in spermatocytes were observed in the real-time PM_2.5 exposure animal model. In addition, significant alterations in key biomarkers of iron metabolism and ferroptosis were found in testis tissues. Notably decreased cell viability was found in vitro. Moreover, the ferroptosis pathway was significantly enriched in the transcriptome enrichment analysis. Subsequent experiments showed that the two core events of ferroptosis, iron overload and lipid peroxidation, occurred in spermatocytes after PM_2.5 treatment. Moreover, lipid metabolic genes (Acsl4 and Aloxe3) and the antioxidant gene Gpx4 were found to be key target genes of ferroptosis caused by PM_2.5 in spermatocytes. Importantly, further studies showed that the damaging effect could be reversed by the iron chelator deferoxamine mesylate (DFOM) and the lipid peroxidation inhibitor ferrostatin-1 (Fer-1), which further confirmed the role of ferroptosis in PM_2.5 toxicity. Our study revealed the vital role of ferroptosis in PM_2.5-induced male reproductive damage, providing novel insights into the air pollution-induced decrease in male fertility.

Semen damage contributed over 50 % to air-pollutant-induced infertility: A prospective cohort study of 3940 men in China

OBJECTIVE

To investigate the contribution of ambient air pollutants-induced semen damage to infertility risk, after identifying dose-response relationship between pollutants and semen parameters and susceptibility window.

METHODS

In Preconception Reproductive Health and Birth Outcomes Cohort, 3940 male volunteers aged 22-49 were recruited from November 2018 to April 2021. At enrollment, resident address information was obtained and semen parameters were examined. During prospective follow-up, infertility was defined as failure to achieve pregnancy after unprotected intercourse within 12 months. Full coverage of ambient pollutant (PM2.5, PM10, SO2, NO2, O3, CO) concentrations was estimated by machine learning algorithms and assigned to individual level. Association between pollutants and semen parameters was analyzed by single- and two-pollutant linear regression. Four potential susceptibility windows were analyzed: lag 0-9d, lag 10-14d, lag 70-90d and lag 0-90d. Pollutant joint effects on semen parameters were analyzed by Bayesian kernel machine regression. Mediating effect of semen parameters on the association between pollutants and infertility was analyzed. False-positive rate was controlled by Bonferroni correction.

RESULTS

Single- and two-pollutant models showed SO2, O3, PMs and NO2 were negatively associated with progressive motility, total motility and sperm morphology, among which, each IQR increase in SO2 at lag 0-90d was associated with -4.13 %(95%CI:-6.25 %, -1.95 %, P < 0.001) change of normal morphology, and O3 at lag 0-90d was negatively associated with progressive motility and total motility (β = -3.64 %, 95%CI:-5.63 %, -1.61 %; β = -2.24 %, 95%CI:-3.38 %, -1.08 %, P < 0.001). Joint effect analysis showed a negative effect on sperm concentration and a suggestive effect on vitality. Mediating effect analysis showed sperm normal morphology had a substantial mediating effect in the association of SO2 with infertility (59.68 %, P < 0.001).

CONCLUSION

Multiple air pollutants may introduce semen quality in the population at entire window of spermatogenesis, among which SO2 needs especial attention, as its damage on sperm morphology may increase risk of infertility.

Sperm telomere length is associated with sperm nuclear DNA integrity and mitochondrial DNA abnormalities among healthy male college students in Chongqing, China

STUDY QUESTION

Is sperm telomere length (STL) associated with sperm nuclear DNA damage and mitochondrial DNA abnormalities?

SUMMARY ANSWER

Sperm telomere length is related to sperm nuclear DNA integrity and mitochondrial DNA abnormalities in healthy young college students.

WHAT IS KNOWN ALREADY

Many studies have revealed the correlations between sperm genetic alterations in both the nucleus and mitochondria and sperm functionality, however, the possible associations between the telomere, an important component of chromosome, and conventional indicators of mitochondrial DNA and nuclear DNA changes have not been investigated.

STUDY DESIGN, SIZE, DURATION

A prospective cohort study, Male Reproductive Health in Chongqing College Students (MARHCS), was conducted from June 2013 to June 2015. We pooled data collected from the follow-up study in 2014 and a total of 444 participants were included.

PARTICIPANTS/MATERIALS, SETTING, METHODS

STL was measured by quantitative (Q)-PCR. Sperm nuclear DNA integrity was determined using sperm chromatin structure assay (SCSA) and comet assay. Mitochondrial DNA damage was assessed by mitochondrial DNA copy number (mtDNAcn) evaluated with Q-PCR, and mtDNA integrity was determined with long PCR.

MAIN RESULTS AND THE ROLE OF CHANCE

The univariable-linear regression analysis revealed that STL was significantly positively correlated with markers of sperm nuclear DNA damage including the DNA fragmentation index (DFI) and comet parameters (the percentage of DNA in the tail, tail length, comet length, and tail moment). Additionally, STL was also significantly positively correlated with mtDNAcn and significantly negatively correlated with mtDNA integrity. After adjustment for potential confounders, these relationships remained appreciable. Moreover, we investigated potential effects of biometric factors, including age, parental age at conception, and BMI on STL and found that STL was increased with paternal age at conception.

LIMITATIONS, REASONS FOR CAUTION

A mechanistic explanation of the correlation between STL, sperm nuclear DNA integrity, and mtDNA abnormalities cannot be provided with a cross-sectional study design, so well-designed longitudinal studies are still necessary. In addition, a single semen samples were provided and were not all obtained at the same time point, which may increase the intraindividual bias in this study.

WIDER IMPLICATIONS OF THE FINDINGS

The findings extend the literature including assessment of mitochondrial dysfunction, sperm nuclear DNA damage, and telomere length and provide new insights into the relevance of STL in male reproduction.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by the National Natural Science Foundation of China (No. 82073590), the National Natural Science Foundation of China (No. 81903363), the National Natural Science Foundation of China (No. 82130097), and the National Key R&D Program of China (2022YFC2702900). The authors declare no conflicts of interest.

TRIAL REGISTRATION NUMBER

N/A.

Lnc-HZ03 promotes TRBP-mediated splicing of pre-miR-hz03 to generate miR-hz03 in human trophoblast cells

Benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide (BPDE) leads to dysfunctions of human trophoblast cells and further induces miscarriage. In our previous study, we have found that lnc-HZ03 and miR-hz03 are upregulated in BPDE-exposed human trophoblast cells and in recurrent miscarriage tissues; and the upregulated miR-hz03 caused by lnc-HZ03 further promotes the apoptosis of human trophoblast cells and induces miscarriage. However, how lnc-HZ03 upregulates miR-hz03 is completely unknown. In this study, we find that lnc-HZ03 upregulates the expression level of a transcription factor TFIID (a TATA-binding protein) and promotes TFIID-mediated transactivation response element RNA-binding protein (TRBP) transcription. Subsequently, the upregulated TRBP promotes the maturation of miR-hz03 by splicing its precursor pre-miR-hz03 in human trophoblast cells. In BPDE-exposed trophoblast cells or in recurrent miscarriage tissues, lnc-HZ03 was upregulated, which accelerates the TFIID-mediated TRBP transcription and thus promotes TRBP-mediated miR-HZ03 maturation. Subsequently, the upregulated miR-hz03 further promotes the apoptosis of human trophoblast cells and induces miscarriage. This work provides new insights into the regulation of miRNA expression levels by lncRNAs in BPDE-exposed human trophoblast cells.

Lifestyle-related risk factors correlated with mental health problems: A longitudinal observational study among 686 male college students in Chongqing, China

Aim

Public concerns over the mental health problems of college students are rising. Previous research show that female tend to suffer more from mental health problems than males, with few studies focusing on males. This study sought to explore the association of lifestyle-related risk factors with the prevalence of mental health problems among male college students in China.

Methods

The lifestyle information and mental health status of 686 male college students from Chongqing, China, were assessed in 2014, and 582 of them were followed up a year later. Participants completed a questionnaire assessing demographic and lifestyle factors which include sleep quality, computer usage, sedentariness, physical activity, smoking, current alcohol, coke, coffee, and milk tea drinking, and current tea/fried food/baked food consumption. Mental health problems were measured using the Depression Anxiety Stress Scale-21 (DASS-21).

Results

Univariate analyses indicated that age, sleep latency, sleep duration, computer usage time, milk tea drinking, and fried food consumption were potential risk factors for mental health problems (p's < 0.05). Multivariate analysis further revealed that, either at baseline or during follow-up, participants with (i) more computer usage time were at a higher risk of having depression symptoms (p's < 0.05) and (ii) a higher frequency of fried food consumption were associated with a higher risk of having depression, anxiety, and stress symptoms (p's < 0.05). Additionally, the cross-lagged analysis showed that (i) computer usage time in 2014 is positively correlated with depression status (β = 0.106, p < 0.05) but not anxiety (β = 0.047, p > 0.05) and stress (β = 0.019, p > 0.05) status a year later and (ii) fried food consumption in 2014 is positively correlated with depression (β = 0.129, p < 0.01), anxiety (β = 0.168, p < 0.001), and stress (β = 0.113, p < 0.01) status a year later.

Conclusions

Computer usage time and fried food consumption were lifestyle-related risk factors for mental health problems in male college students in Chongqing, China. These results might emphasize further preventive strategies for mental health problems, especially in male college students.

Genome-wide alternation and effect of DNA methylation in the impairments of steroidogenesis and spermatogenesis after PM2.5 exposure

The effects of ambient fine particles on male reproductive health have raised widespread concern. The particular underlying mechanisms of the damage remain largely unclear and demand more research in new directions. Previous research has revealed that DNA methylation plays an important role in male reproductive development and is also vulnerable to environmental influences. However, there hasn't been enough investigation into the involvement of DNA methylation in PM_2.5-induced male reproductive toxicity. Here, we establish a real-time PM_2.5 exposure model and revealed that PM_2.5 exposure could lead to testicular dysfunction including spermatogenesis impairment and steroid hormone dysfunction. In particular, the decrease in the testicular global level of 5-methylcytosine (5mC) indicated a possible association of DNA methylation with testicular injury induced by PM_2.5 exposure. Further genome-wide methylation analysis revealed genomic hypomethylation of testicular DNA and identified more than 1000 differentially methylated regions in both CAP and UA versus FA, indicating that PM_2.5 exposure, even low-dose, could modulate the testicular methylome. Furthermore, integrated analysis of methylome and transcriptome identified some key methylated genes and networks, which may be involved in spermatogenesis and synthesis of steroid hormone. The testicular methylation levels of key genes especially Cyp11a1 and Pax8 raised, and their consequent reduced expression may impair the testosterone and sperm production process. Our research provides fundamental knowledge as well as novel insights into the possible involvement of DNA methylation in PM_2.5-induced male reproductive harm.

Benzo[a]pyrene inhibits testosterone biosynthesis via NDUFA10-mediated mitochondrial compromise in mouse Leydig cells: Integrating experimental and in silico toxicological approaches

Benzo[a]pyrene (B[a]P), a representative of polycyclic aromatic hydrocarbons (PAHs), is ubiquitously spread in the environment and showing deleterious impacts on male steroidogenesis, including testosterone synthesis disorder. However, the precise mechanisms involved in B[a]P-induced steroidogenesis perturbation remains obscure. In the present study, we integrated in vivo tests, transcriptome profiling, in vitro assays, and conjoint in silico toxicological approaches to delineate the detailed mechanisms. In mouse models, we observed that B[a]P administration remarkably inhibited testosterone synthesis accompanied by ultrastructural impairments of mitochondria and mitophagosome formation in mouse Leydig cells. Transcriptome profiling showed that B[a]P down-regulated the expression of Ndufa9, Ndufa6, Ndufa10, and Ndufa5 in mouse testes, which are identified as critical genes involved in the assembly and functionality of mitochondrial complex I. In the in vitro tests, the bioactive B[a]P metabolite BPDE induced perturbation of testosterone synthesis by NDUFA10-mediated mitochondrial impairment, which was further exacerbated by mitophagy in TM3 Leydig cells. The findings of in silico toxicological analyses were highly consistent with the experimental observations and further unveiled that B[a]P/BPDE-involved PPARα activation could serve as a molecular initiating event to trigger the decline in Ndufa10 expression and testosterone synthesis. Overall, we have shown the first evidence that mitochondrial compromise in Leydig cells is the extremely crucial target in B[a]P-induced steroidogenesis perturbation.

Associations between isoflavone exposure and reproductive damage in adult males: evidence from human and model system studies

It's controversial whether exposure to isoflavones, constituents of certain plants such as soy bean, exerts male reproductive toxicity. This study was designed to investigate whether isoflavone exposure during adulthood could have deleterious impacts on male reproductive health by the cross-sectional study, animal experiments, and in vitro tests. In the cross-sectional study, we observed that urinary isoflavones were not significantly associated with semen quality including sperm concentrations, sperm count, progressive motility, and total motility, respectively (All P-value for trend>0.05). However, negative associations were found between plasma testosterone and urinary Σisoflavones, genistein, glycitein, and dihydrodaidzein (all P-value for trend <0.05). In the animal experiments, serum and intratesticular testosterone levels were decreased in mice exposed to several dosages of genistein. Genistein administration caused up-regulation of estrogen receptor alpha (ERα) and down-regulation of cytochrome P45017A1 (CYP17A1) protein levels in testes of mice. However, genistein treatment during adulthood did not induce appreciable structural damages of reproductive system in mice. In vitro tests, we observed that genistein of different dosages (0.01, 2.5, 10 μM) caused a concentration dependent inhibition of testosterone production by TM3 Leydig cells (half-maximal inhibitory concentration = 3.796 nM, P < 0.05). Elevated protein expression of ERα and decreased mRNA/protein level of CYP17A1 were also observed in genistein-treated cells. Protein level of CYP17A1 and testosterone concentration were significantly restored in the ERα siRNA-transfected cells, compared to cells that treated with genistein alone (P < 0.05). The results demonstrate that exposure to isoflavones during adulthood may be associated with alterations of reproductive hormones. Particularly for genistein, which inhibits testosterone biosynthesis through up-regulation of ERα in Leydig cells of mice, might induce the disruption of testosterone production in human. The present study provides novel perspective into potential targets for male reproductive compromise induced by isoflavone exposure.

[Preconception reproductive health and birth outcome cohort in Chongqing: the cohort profile]

Birth cohort is an important platform to study the effect of early-life exposure on health outcome, but large cohorts to investigate the effect of preconception exposure, especially paternal exposure, on reproductive health and birth outcome are limited. The Preconception Reproductive Health and Birth Outcome Cohort (PREBIC) is a prospective birth cohort study which pays equal attention to the contribution of environmental, psychological, behavioral as well as other factors to reproductive health and adverse birth outcomes in both men and women in Chongqing, China. PREBIC started in 2019 and plans to recruit 20 800 reproductive-age couples with child-bearing willingness. Followed up was conducted to understand the conception status of the women within two years. Women in pregnancy would be visited at first, second, third trimesters and after delivery. The offspring would be monitored until 2 years old to understand the incidences of preterm birth, low birth weight, birth defects, neurodevelopmental disorders and other outcomes. Related information and biospecimen collections (including semen, peripheral blood, urine, placenta, umbilical cord, cord blood and oral swab) were scheduled in each period. By January 2022, PREBIC had recruited 8 698 participants from all 38 districts in Chongqing. The goal of PREBIC is to establish one of the largest prospective preconception birth cohorts covering both men and women, which might provide a unique insight to understand the effects of the full reproductive cycle on reproductive health and adverse outcomes, with especial emphasis on preconception exposures.

Low-level and combined exposure to environmental metal elements affects male reproductive outcomes: Prospective MARHCS study in population of college students in Chongqing, China

BACKGROUND

Male fertility has shown a continuously declining tendency for decades. Over exposure to metal/metalloid elements has been proposed as associated with reproductive impairment. However, the hazard profile remained unclear in general public experiencing low-level and combined metal exposure.

METHODS

Based on the MARHCS cohort in Chongqing, China, 796 college students were recruited from June 2013 and 666 subjects were followed up next year. At each phase, semen and blood samples were collected for an assessment of semen quality and six sex hormones levels. Eighteen urinary metal/metalloid elements were quantified by ICP-MS as internal exposure biomarkers. Cluster analysis was conducted to characterize reproductive outcomes in the subgroups for different overall estimated exposure levels. Effects of each metal/metalloid element were analyzed using multiple statistical strategies: single-element mixed model, multiple-elements model and self before-after comparison design.

RESULTS

The urine concentration for 18 metal/metalloid elements was at a typically lower level (far away from the exposure limits) and positively associated with each other. After adjustment of the potential confounders, a decrease of 11.53% (95% CI: -18.61, -3.84%) and 10.84% (95% CI: -17.93, -3.14%) in spermatid morphology was observed in the highest quantile groups of vanadium (V) and nickel (Ni), respectively. Urinary silver (Ag) was dose-dependent associated with an increase in total sperm number (6.91%, 95% CI: 1.14, 13.00%), sperm concentration (16.38%, 95% CI: 5.15, 28.81%) and semen volume (23.73%, 95% CI: 10.46, 38.60%). Further, hormone testosterone presented a significant decrease in subgroup with higher overall estimated exposure and a stable negative association with lithium (Li). The above relationships remained significant across different statistical strategies (all p values <0.05).

CONCLUSION

Our study provided new evidences that exposure to metal/metalloid elements potentially exert bidirectional influences on semen quality at a relatively low level. And serum testosterone appears as a vulnerable index for metal exposure.

Analysis by transcriptomics and metabolomics for the proliferation inhibition and dysfunction through redox imbalance-mediated DNA damage response and ferroptosis in male reproduction of mice and TM4 Sertoli cells exposed to PM2.5

Sertoli cells play a pivotal role in the complex spermatogenesis process. This study aimed to investigate the effects of PM_2.5 on Sertoli cells using the TM4 cell line and a real time whole-body PM_2.5 exposure mouse model, and further explore the underlying mechanisms through the application of metabolomics and transcriptomics. The results in vivo and in vitro showed that PM_2.5 reduced Sertoli cells number in seminiferous tubules and inhibited cell proliferation. PM_2.5 exposure also induced Sertoli cell dysfunction by increasing androgen binding protein (ABP) concentration, reducing the blood-testis barrier (BTB)-related protein expression, and decreasing glycolysis capacity and lactate production. The results of transcriptomics, metabolomics, and integrative analysis of multi-omics in the TM4 Sertoli cells revealed the activation of xenobiotic metabolism, and the disturbance of glutathione and purine metabolism after PM_2.5 exposure. Further tests verified the reduced GSH/GSSG ratio and the elevation of xanthine oxidase (XO) activity in the PM_2.5-exposed TM4 cells, indicating that excessive reactive oxygen species (ROS) was generated via metabolic disorder caused by PM_2.5. Moreover, the redox imbalance was proved by the increase in the mitochondrial ROS level, superoxide dismutase (SOD) and catalase (CAT) activity, as well as the activation of the Nrf2 antioxidative pathway. Further study found that the redox imbalance caused by PM_2.5 induced DNA damage response and cell cycle arrest. Additionally, PM_2.5 induced ferroptosis through iron overload and lipid peroxidation. Taken all together, our study provided new insights for understanding proliferation inhibition and dysfunction of TM4 Sertoli cells exposed to PM_2.5 via metabolic disorder and redox imbalance-mediated DNA damage response and ferroptosis.

Antibody-mediated blockade of the IL23 receptor destabilizes intratumoral regulatory T cells and enhances immunotherapy

Regulatory T cells (Treg) can impede antitumor immunity and currently represent a major obstacle to effective cancer immunotherapy. Targeting tumor-infiltrating regulatory Treg while sparing systemic Treg represents an optimal approach to this problem. Here, we provide evidence that the interleukin 23 receptor (IL23R) expressed by tumor-infiltrating Treg promotes suppressive activity. Disruption of the IL23R results in increased responsiveness of destabilized Treg to the IL12 cytokine, the production of γ-interferon, and the recruitment of CD8 T cells that inhibit tumor growth. Since the Treg destabilization pathway that is initiated by IL23R blockade is distinct and independent from the destabilization pathway coupled to glucocorticoid-induced TNFR-related protein (GITR) activation, we examined the impact of the coordinate induction of the two destabilization pathways on antitumor immune responses. Combined GITR and IL23R antibody treatment of mice inoculated with MC38 tumors resulted in robust and synergistic antitumor responses. These findings indicate that the delineation of independent Treg destabilization pathways may allow improved approaches to the development of combination immunotherapy for cancers.

Flow Cytometric Analysis of Biomarkers for Detecting Human Sperm Functional Defects

The conventional semen parameter analysis is widely used to assess male fertility. However, studies have found that ~15% of infertile patients show no abnormalities in conventional semen parameters. Additional technologies are needed to explain the idiopathic infertility and detect subtle sperm defects. Currently, biomarkers of sperm function, including sperm apoptosis, mitochondrial membrane potential (MMP), and DNA damage, reveal sperm physiology at the molecular level and are capable of predicting male fertility. With flow cytometry (FCM) techniques, each of these markers can be rapidly, accurately, and precisely measured in human semen samples, but time costs substantially increase and results could be obstructed if all the biomarkers need to be tested with a single cytometer. In this protocol, after collection and immediate incubation at 37 °C for liquefication, semen samples were further analyzed for sperm apoptosis using Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) staining. The MMP was labeled with 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl-benzimidazolylcarbocyanine iodide (JC-1) probe, and DNA damage was assessed using the sperm chromatin structure assay (SCSA) with acridine orange (AO) staining. Thus, flow cytometric analysis of sperm function markers can be a practical and reliable toolkit for the diagnosis of infertility and evaluation of sperm function at both bench and bed.

The Microsoft Academic Knowledge Graph Enhanced: Author Name Disambiguation, Publication Classification, and Embeddings

Although several large knowledge graphs have been proposed in the scholarly field, such graphs are limited with respect to several data quality dimensions such as accuracy and coverage. In this article, we present methods for enhancing the Microsoft Academic Knowledge Graph (MAKG), a recently published large-scale knowledge graph containing metadata about scientific publications and associated authors, venues, and affiliations. Based on a qualitative analysis of the MAKG, we address three aspects. First, we adopt and evaluate unsupervised approaches for large-scale author name disambiguation. Second, we develop and evaluate methods for tagging publications by their discipline and by keywords, facilitating enhanced search and recommendation of publications and associated entities. Third, we compute and evaluate embeddings for all 254 million authors, 210 million papers, 49,000 journals, and 16,000 conference entities in the MAKG based on several state-of-the-art embedding techniques. Finally, we provide statistics for the updated MAKG. Our final MAKG is publicly available at https://makg.org and can be used for the search or recommendation of scholarly entities, as well as enhanced scientific impact quantification.

Peer Review

https://publons.com/publon/10.1162/qss_a_00183

[Very low-level viremia: new clinical attention-requiring problem during the course of anti-hepatitis B virus treatment]

Clinical studies have validated low-level viremia is associated with a variety of adverse outcomes in patients with chronic hepatitis B during the course of receiving nucleos(t)ide analogue antiviral therapy. With the advancement of PCR technology, the high sensitivity PCR detection of HBV DNA can reach the lower limit of detection of < 5-10 IU/mL. The standard criterion for judging among patients who have achieved complete virological response is HBV DNA levels < 20 IU/ml. The use of highly sensitive PCR tests can detect very low-level viremia (HBV DNA < 20 IU/ml, but > 5-10 IU/mL) in some patients. However, there are currently fewer relevant studies, and more research data needs to be accumulated to answer this clinical question of whether long-term very low-level viremia affects the clinical outcome of patients with chronic hepatitis B.

Folate metabolism modifies chromosomal damage induced by 1,3-butadiene: results from a match-up study in China and in vitro experiments

OBJECTIVES

To explore the role of folate metabolism in 1,3-Butadiene (BD)'s genotoxicity, we conducted a match-up study in BD-exposed workers in China to analyze the associations between the polymorphisms of methylenetetrahydrofolate reductase (MTHFR) and the chromosomal damage induced by BD exposure, and culture-based experiments in TK-6 cells to examine the global DNA methylation levels and chromosomal damage when exposed both to BD's genotoxic metabolite, 1,2:3,4-diepoxybutane (DEB), and MTHFR's direct catalytic product, 5-methyltetrahydrofolate (5-MTHF).

METHODS

Cytokinesis block micronucleus assay (CBMN) was used to examine the chromosomal damage induced by BD or DEB. Poisson regression models were produced to quantify the relationship of chromosomal damage and genetic polymorphisms in the BD-exposed workers. Global DNA methylation levels in TK6 cells were examined using DNA Methylation Quantification Kit.

RESULTS

We found that BD-exposed workers carrying MTHFR C677T CC (2.00 ± 2.00‰) (FR = 0.36, 95%CI: 0.20-0.67, P < 0.01) or MTHFR C677T CT (2.87 ± 1.98‰) (FR = 0.49, 95%CI: 0.32-0.77, P < 0.01) genotypes had significantly lower nuclear bud (NBUD) frequencies than those carrying genotype MTHFR 677 TT (5.33 ± 2.60‰), respectively. The results in TK6 cells showed that there was a significant increment in frequencies of micronucleus (MN), nucleoplasmic bridge (NPB) and nuclear bud (NBUD) with exposure to DEB at each 5-MTHF dose (ANOVA, P < 0.01). Additionally, there was a significant decrease in frequencies of MN, NPB and NBUD in DEB-exposed cultures with increasing concentration of 5-MTHF (ANOVA, P < 0.05). The levels of global DNA methylation were significantly decreased by DEB treatment in a dose-dependent manner within each 5-MTHF concentration in TK-6 cells (ANOVA, P < 0.01), and were significantly increased by 5-MTHF supplementation within each DEB concentration (ANOVA, P < 0.01).

CONCLUSION

We reported that folate metabolism could modify the association between BD exposure and chromosomal damage, and such effect may be partially mediated by DNA hypomethylation, and 5-MTHF supplementation could rescue it.

Exposure to fine particulate matter-bound polycyclic aromatic hydrocarbons, male semen quality, and reproductive hormones: The MARCHS study

Exposure to outdoor fine particulate matter (PM_2.5)-bound polycyclic aromatic hydrocarbons (PAHs) is linked to reproductive dysfunction. However, it is unclear which component of PAHs is responsible for the adverse outcomes. In the Male Reproductive Health in Chongqing College Students (MARHCS) cohort study, we measured the exposure levels of 16 PAHs by collecting air PM_2.5 particles and assessed eight PAHs metabolites from four parent PAHs, including naphthalene, fluorene, phenanthrene, and pyrene in urine samples. We investigated compositional profiles and variation characteristics for 16 PAHs in PM_2.5, and then assessed the association between PAHs exposure and semen routine parameters, sperm chromatin structure, and serum hormone levels in 1452 samples. The results showed that naphthalene (95% CI: -17.989, -8.101), chrysene (95% CI: -64.894, -47.575), benzo[a]anthracene (95% CI: -63.227, -45.936) and all the high molecular weight (HMW) PAHs in PM_2.5 were negatively associated with sperm normal morphology. Most of the low molecular weight (LMW) PAHs, such as acenaphthylene, fluorene, phenanthrene, fluoranthene, pyrene, chrysene, benzo[a]anthracene, ∑LMW PAHs and ∑16 PAHs, were correlated with increased sperm motility (all corrected P < 0.05). On the other hand, sperm normal morphology was all negatively associated with urinary metabolites of ∑OH-Nap (95% CI: -5.611, -0.536), ∑OH-Phe (95% CI: -5.741, -0.957), and ∑OH-PAHs (95% CI: -5.274, -0.361). Urinary concentrations of ∑OH-PAHs were found to be negatively associated with sperm high DNA stainability (HDS) (P = 0.023), while ∑OH-Phe were negatively associated with serum testosterone level and sperm HDS (P = 0.004). Spearman correlation analysis showed that except for the urinary OH-Nap metabolites, the rest of the urinary OH-PAHs metabolites were negatively correlated with their parent PAHs in air. The results of this study suggest that various PAHs' components may affect reproductive parameters differently. Inhalation of PAHs in air, especially HMW PAHs, may be a potential risk factor for male reproductive health.

Acute effects of short-term exposure to ambient air pollution on reproductive hormones in young males of the MARHCS study in China

Air pollution, which is associated with male reproductive health. However, it is unknown the acute effects of ambient air pollutants exposure on male reproductive hormones. The current study, we measured serum levels of reproductive hormone in 2030 blood samples gathered from The Male Reproductive Health in Chongqing College Students (MARHCS) cohort study. We derived a full coverage of ambient air pollutant (PM₁₀, PM_2.5, SO₂, NO₂, CO and O₃) concentrations by employing machine learning algorithms, and used a mixed-effect model to estimate single-day and cumulative effects of air pollutants exposure on serum reproductive hormones. Our results showed that (1) PM₁₀ and PM_2.5 concentrations were positively associated with estradiol (E₂) in both single and cumulative lag days, but were negatively associated with the ratio of Testosterone/E₂ (the T/E₂ ratio). NO₂ was positively associated with estradiol at lag day 2 (95% CI: 0.290, 0.881; corrected P = 0.048) and lag 0-2 days (95% CI: 0.523, 1.337; corrected P = 0.003), with progesterone (P) at lag day 2 and lag day 3 (corrected P < 0.05). There was also a positive association between CO exposure and progesterone at lag day 2. (2) SO₂ was inversely associated with E₂ at lag day 3, 4 and lag 0-4 days, and progesterone at lag day 0, 1, 2 and lag 0-1, 0-2, 0-4 days, but positively associated with the T/E₂ ratio at lag day 3, 4 and lag 0-4 days (corrected P < 0.05). O₃ exposure was negatively associated with E₂ at lag day 3 (95% CI: -0.216, -0.074, corrected P = 0.03). (3) No significant associations were found between the cumulative daily average air pollutant exposure of CO, O₃ and hormone outcomes. This study suggests that short-term exposure to air pollutants may thus alter reproductive hormone levels, especially on serum estradiol, progesterone levels and the T/E₂ ratio.

Blood lead levels and their associated risk factors in Chinese adults from 1980 to 2018

In China, studies on lead exposure to grownup are scarce compared to children, although relevant disease burdens for adults are much severe than that in developed countries. The present study evaluated blood lead levels (BLLs) in Chinese adults by data mining using Monte Carlo simulation. A total of 115 scientific studies published between January 1980 and March 2021 reflecting 45,514 Chinese adults were included in the study. After a continuous increase in Chinese adult BLLs from 1980-1983 (GM 74.84 μg/L) to 1994-1996 (GM 92.27 μg/L), BLLs began to decline from 2000--2002 (GM 80.32 μg/L) to 2016-2018 (GM 21.57 μg/L). This decline implied that the lead phase-out policy in gasoline was effective over the past two decades. The study indicated that North, South, and Southwest China were still relatively high compared to other regions in the past decade. Statistical analysis showed that BLLs of males (GM 68.45 μg/L) were higher than females (GM 56.51 μg/L), smokers (GM 80.96 μg/L) higher than nonsmokers (GM 58.95 μg/L), and populations over 40 (GM 40.43 μg/L) higher than younger populations (GM 40.37 μg/L). The significantly positive correlation between the concentrations of PM2.5 and topsoil lead and BLLs in Chinese adults indicated that air and soil pollution affect adult BLLs. Taken together, our results showed that strict lead control strategies and regular bio-monitoring are needed to maintain low BLLs in the population.

An exposomic approach with 138 chemical and non-chemical exposures to predict 32 biomarkers of male reproductive damages: A case study of college students in Chongqing, China

Male reproductive damage in the general population comprises different disorders in various biomarkers, which could be respectively caused by a number of exposure factors. However, researchers considering the environmental/behavioral/psychological exposures together to evaluate their contribution to male reproductive damage are still lacking. The present study investigated the comprehensive association between 138 environmental/behavioral/psychological exposures and 32 male reproductive biomarkers in 796 young Chinese men using graph-guided fused lasso (GFLASSO) and hierarchical clustering methods. All biomarkers were found to be associated with various exposures. A combination of these exposures not only predicted the levels of single biomarkers in another test dataset, but also identified the comprehensive reproductive features by clustering the men into five subgroups with distinct damages representing disrupted spermatogenesis with abnormal sperm morphology, low sperm motility with DNA fragmentation, chromatin immaturity, aberrant endocrine, or DNA strand breakage. The findings can be used to suggest a novel way to identify the males with a high risk of reproductive damage and develop personalized preventive strategies.

Adverse effects of circadian desynchrony on the male reproductive system: an epidemiological and experimental study

STUDY QUESTION

Is circadian desynchrony a risk factor of male reproductive damage in semen parameters and/or reproductive hormones?

SUMMARY ANSWER

Circadian desynchrony correlates with decrease of sperm count, which was improved when circadian desynchrony was attenuated.

WHAT IS KNOWN ALREADY

Circadian desynchrony caused by work (shift work) and non-work-related reasons is prevalent worldwide and has been found to be associated with decreased female fertility, but whether it harms male reproductive health is unclear.

STUDY DESIGN, SIZE, DURATION

A hybrid research was conducted. (i) A cross-sectional study of 1346 Chinese men in 2007 was used to analyze the association between semen/hormone biomarkers and work-related circadian desynchrony, which was divided into rotating shift work and permanent shift work against non-shift work. (ii) A cohort of 796 Chinese undergraduates from 2013 to 2014 was used to analyzed the association between semen/hormone biomarkers and non-work-related circadian desynchrony (between school days and days off). (iii) The biomarker identified simultaneously in both populations was further validated in male C57BL/6J mice housed under conditions simulating circadian desynchrony.

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 17 semen/hormone biomarkers were compared among rotating shift workers and permanent shift workers against non-shift workers in the 1346 reproductive-age Chinese men. A total of 14 semen/hormone biomarker was analyzed in the undergraduate cohort for correlation with non-work-related circadian desynchrony (measured by Munich Chronotype Questionnaire) in 2013 and 2014 and compared between the 2 years. Photoperiod-shifting method was used to establish the mouse model, in which the biomarker was examined and molecular mechanism was explored by apoptosis analysis, DNA content analysis, transcriptome sequencing, real-time PCR and western blotting.

MAIN RESULTS AND THE ROLE OF CHANCE

Among the semen/hormone biomarkers, sperm count was found to be lower in rotating shift workers, who had a higher risk of low sperm count defined by Chinese Ministry of Health (total sperm/ejaculate < 120 × 10⁶) than non-shift workers (odds ratio = 1.26, 95% CI 1.05–1.52). This biomarker was replicated in the undergraduate cohort, where each hour of circadian desynchrony was associated with 1.16 (95% CI 1.02–1.31) fold odds of low sperm count, and sperm count increased during 2014 in men who reduced circadian desynchrony after 2013. A decrease of sperm count with circadian desynchrony and its recovery after removal of circadian desynchrony was also observed in the mouse model. During asynchrony, increased apoptosis was found in seminiferous tubules and the marker genes of post-spermatocyte stage cells were down-regulated. The most enriched functional pathway was homologous recombination, which happened during meiosis.

LIMITATIONS, REASONS FOR CAUTION

The study of human beings was observational while the animal study has potential difference in circadian desynchrony exposure and species susceptibility. Further researches are needed to clarify the causal relationship in men.

WIDER IMPLICATIONS OF THE FINDINGS

These findings provide novel insight to the effect of circadian desynchrony on male reproductive health and a potential strategy for prevention of reproductive damage.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by the National Key R&D Program of China [2017YFC1002001] and National Natural Science Foundation of China [81871208]. There are no conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

NA.

Upregulated lnc-HZ02 and miR-hz02 inhibited migration and invasion by downregulating the FAK/SRC/PI3K/AKT pathway in BPDE-treated trophoblast cells

BPDE (benzo(a)pyren-7,8-dihydrodiol-9,10-epoxide), a metabolite of environmental carcinogenic BaP, weakens the migration and invasion of human villous trophoblast cells and may further induce miscarriage. However, the underlying mechanisms remain largely unknown. In this study, we identified that in trophoblast Swan 71 and HTR-8/SVneo cells, miR-hz02 upregulates the level of lnc-HZ02, which inhibits the expression of an RNA-binding protein HuR. HuR could interact with FAK mRNA and promote its mRNA stability, thus upregulating the FAK level and the FAK/SRC/PI3K/AKT pathway, and finally maintaining the normal migration and invasion of trophoblast cells. If trophoblast cells are exposed to BPDE, both miR-hz02 and lnc-HZ02 are upregulated, which reduce the level of HuR, weaken the interactions of HuR with FAK mRNA, downregulate FAK level and the FAK/SRC/PI3K/AKT pathway, and finally inhibit cell migration and invasion. This study provides a novel scientific understanding of the dysfunctions of human trophoblast cells.

Sleep behavior is associated with over two-fold decrease of sperm count in a chronotype-specific pattern: path analysis of 667 young men in the MARHCS study

Recent studies have shown that the reduction of sperm count is associated with sleep behaviors, including restricted/excessive sleep duration, late sleep time midpoint, and shift of sleep midpoint time (social jetlag). Chronotype is suggested to regulate sleep behaviors; however, the relationship between chronotype and human sperm count is unknown. The relationship between sleep behaviors and human sperm count, when sleep behaviors as well as chronotype are controlled is also unclear. We performed a path analysis of the data obtained from 667 Chinese men recruited into the MARHCS (Male Reproductive Health in Chongqing College Students) study. Chronotype, sleep duration, sleep time midpoint, and social jetlag were estimated by the Munich Chronotype Questionnaire. Sperm count was measured by computer-aided sperm analysis. The comprehensive relationship between chronotype, all sleep behaviors, and sperm count was tested by path analysis, in which the standardized residual of sperm count was used for adjustment of age, abstinence period, body mass index, tobacco smoking, alcohol drinking, and intake of tea, cola, and coffee. Our major findings are: (1) Chronotype negatively correlated with sleep duration (correlation coefficient (R) = -0.32, P < .001) and positively correlated with sleep midpoint (R = 0.65, P < .001) and social jetlag (R = 0.37, P < .001). (2) Sleep duration (U-shape transformed; R = -0.11, P = .005), sleep midpoint (R = -0.09, P = .021), and social jetlag (R = -0.12, P = .001), respectively, correlated with sperm count in univariate analysis. The relationship between sleep midpoint and sperm count disappeared when social jetlag was controlled. (3) Path analysis showed that chronotype is connected with sperm count through two pathways: via sleep duration (standardized path coefficient = -0.09, 95% CI: -0.17 to -0.01, P = .030) and via social jetlag (standardized path coefficient = -0.09, 95% CI: -0.17 to -0.01, P = .031). For men of earlier, intermediate, and later tertile of chronotype, the sleep-duration-related decrease of sperm count was separately estimated to be 16.3%, 12.8%, and 11.6%, while the social-jetlag-related decrease of sperm count was estimated to be 9.3%, 12.8%, and 19.2%. The total effect of sleep behaviors on sperm count was estimated to be 25.7%, 25.6%, and 30.7%, with an average of 27.4% for men of different chronotypes. The present study showed that men of earlier chronotype were prone to restricted/excessive sleep duration, while men of later chronotype were prone to social jetlag, both of which correlated with reduced sperm count, suggesting that chronotype may modulate the sleep behaviors and exert dual effects on sperm count via different sleep behaviors, leading to a ubiquitous sperm decline. Men of different chronotypes should take care to avoid different types of improper sleep behaviors, so as to prevent such deleterious effect on sperm count.

Artesunate protects immunosuppression mice induced by glucocorticoids via enhancing pro-inflammatory cytokines release and bacterial clearance

Glucocorticoids are commonly used in clinic, but the immunosuppression seriously hinders their usage. Herein, immunomodulatory effect of artesunate (AS) on hydrocortisone (HC)-induced immunosuppression was investigated. HC-induced immunosuppression mice (HC mice) were established by intramuscular administration with HC (20 mg/kg) once a day for 5 consecutive days. The results showed HC mice challenged with Escherichia coli on the sixth day presented a lower ability to clear bacteria, decreased TNF-α in blood, decreased spleen index and thymus index. Significantly, AS (20 mg/kg) treatment not only enhanced the ability of HC mice to clear bacteria, but also increased spleen index, the levels of pro-inflammatory cytokines from 78.7 ± 12.1 ng/ml (TNF-α) and 48.7 ± 8.6 pg/ml (IL-6) to 174.0 ± 90.5 ng/ml and 783.3 ± 90.5 pg/ml, number of white blood cells in blood, and sIgA in colon. Subsequently, HC-induced immunosuppression peritoneal macrophages model (HC cells) was established via addition of HC (0.5 μg/ml) for 0.5 h, and then LPS (100 ng/ml) was added to clarify the functional status of the cells. The results showed HC inhibited TNF-α and IL-6 mRNA expressions and their release, but AS (2.5 μg/ml) could increase TNF-α and IL-6 mRNA expressions and their release. AS inhibited GILZ mRNA up-regulated by HC and increases TLR4/NF-κB p65 expressions down-regulated by HC. Our findings revealed that AS's effect is closely related to the improvement of the TLR4/NF-κB signal transduction pathway via inhibiting the up-regulation of GILZ mRNA, demonstrating AS does possess immunomodulatory effects and is worth further investigation in the future.

Pornography Use Could Lead to Addiction and Was Associated With Reproductive Hormone Levels and Semen Quality: A Report From the MARHCS Study in China

This study aimed to investigate the situations of pornography use among male college students of China, to explore the addiction possibility for pornography use, and to study the associations between pornography use and reproductive hormone levels and semen quality. Five hundred sixty-eight participants met the inclusion criteria and finished all of the questionnaires and hormone level and semen parameter examinations. A majority of participants (except one) had pornography use experience, 94.2% participants started pornography use before college, and 95.9% participants reported they had masturbation experience when using pornography. Early contact to pornography, frequent pornography use, high amount of time spending on pornography use, and frequent masturbation during pornography use were correlated with addiction trends. Earlier pornography use was found to be associated with lower serum prolactin (PRL), follicle-stimulating hormone (FSH), and progesterone (Prog), as well as lower sperm concentration and total sperm count. Higher frequency of pornography use was associated with lower serum estrogen (E₂). In conclusion, pornography use was common among male college students in China. Early contact, high frequent use, and high frequency of masturbation during pornography use could lead to addiction trends and aberrant reproductive hormone levels and semen quality.

Analysis by Metabolomics and Transcriptomics for the Energy Metabolism Disorder and the Aryl Hydrocarbon Receptor Activation in Male Reproduction of Mice and GC-2spd Cells Exposed to PM2.5

Fine particulate matter (PM_2.5)-induced male reproductive toxicity arouses global public health concerns. However, the mechanisms of toxicity remain unclear. This study aimed to further investigate toxicity pathways by exposure to PM_2.5in vitro and in vivo through the application of metabolomics and transcriptomics. In vitro, spermatocyte-derived GC-2spd cells were treated with 0, 25, 50, 100 μg/mL PM_2.5 for 48 h. In vivo, the real-world exposure of PM_2.5 for mouse was established. Forty-five male C57BL/6 mice were exposed to filtered air, unfiltered air, and concentrated ambient PM_2.5 in Tangshan of China for 8 weeks, respectively. The results in vitro and in vivo showed that PM_2.5 exposure inhibited GC-2spd cell proliferation and reduced sperm motility. Mitochondrial damage was observed after PM_2.5 treatment. Increased Humanin and MOTS-c levels and decreased mitochondrial respiratory indicated that mitochondrial function was disturbed. Furthermore, nontargeted metabolomics analysis revealed that PM_2.5 exposure could disturb the citrate cycle (TCA cycle) and reduce amino acids and nucleotide synthesis. Mechanically, the aryl hydrocarbon receptor (AhR) pathway was activated after exposure to PM_2.5, with a significant increase in CYP1A1 expression. Further studies showed that PM_2.5 exposure significantly increased both intracellular and mitochondrial reactive oxygen species (ROS) and activated NRF2 antioxidative pathway. With the RNA-sequencing technique, the differentially expressed genes induced by PM_2.5 exposure were mainly enriched in the metabolism of xenobiotics by the cytochrome P450 pathway, of which Cyp1a1 was the most significantly changed gene. Our findings demonstrated that PM_2.5 exposure could induce spermatocyte damage and energy metabolism disorder. The activation of the aryl hydrocarbon receptor might be involved in the mechanism of male reproductive toxicity.

Generating adverse outcome pathway (AOP) of inorganic arsenic-induced adult male reproductive impairment via integration of phenotypic analysis in comparative toxicogenomics database (CTD) and AOP wiki

BACKGROUND

Inorganic arsenic (iAs) is a worldwide environmental pollutant which exerts complicated and various toxic effects in organisms. Increasingly epidemic studies have revealed the association between iAs exposure and adult male reproductive impairment. Consistent with the proposal for toxicity testing in the 21st century (TT21C), the adverse outcome pathway (AOP) framework may help unravel the iAs-caused molecular and functional changes leading to male reproductive impairment.

METHOD

Combining CTD's phenotype-disease inference data, iAs-phenotypes were anchored to five male reproductive diseases induced by iAs, and local network topological algorithm was applied in prioritizing their interference significance. Through integrating analysis in AOP Wiki knowledge base, filtered phenotypes were linked to key events consisting of AOPs and assembled together based on evidentially upstream and downstream relationships.

RESULTS

A subset of 655 phenotypes were filtered from CTD as potential key events and showed a significant coherence in five reproductive diseases wherein 39 significant phenotypes showed a good clustering features involving cell cycle, ROS and mitochondria function. Two AOP subnetworks were enriched in AOP Wiki where testosterone reduction and apoptosis of sperm served as focus events respectively. Besides, a candidates list of molecular initialing events was provided of which glucocorticoid receptor activation was overall assessed as an example.

CONCLUSION

This study applied computational and bioinformatics methods in generating AOPs for arsenic reproductive toxicity, which identified the imperative roles of testosterone reduction, response to ROS, spermatogenesis and provided a global view about their internal association. Furthermore, this study helped address the existing knowledge gaps for future experimental verification.

Control of Germinal Center Localization and Lineage Stability of Follicular Regulatory T Cells by the Blimp1 Transcription Factor

Follicular regulatory T (T_FR) cells are a specialized suppressive subset that controls the germinal center (GC) response and maintains humoral self-tolerance. The mechanisms that maintain T_FR lineage identity and suppressive activity remain largely unknown. Here, we show that expression of Blimp1 by FoxP3⁺ T_FR cells is essential for T_FR lineage stability, entry into the GC, and expression of regulatory activity. Deletion of Blimp1 in T_FR cells reduced FoxP3 and CTLA-4 expression and increased pro-inflammatory cytokines and spontaneous production of autoantibodies, including elevated IgE. Maintenance of T_FR stability reflected Blimp1-dependent repression of the IL-23R-STAT3 axis and activation of the CD25-STAT5 pathway, while silenced IL-23R-STAT3 or increased STAT5 activation rescued the Blimp1-deficient T_FR phenotype. Blimp1-dependent control of CXCR5/CCR7 expression also regulated T_FR homing into the GC. These findings uncover a Blimp1-dependent T_FR checkpoint that enforces suppressive activity and acts as a gatekeeper of GC entry.

Poorer sleep quality correlated with mental health problems in college students: A longitudinal observational study among 686 males

OBJECTIVE

Poor sleep quality and mental health problems are common in college students. The objective of this study is to examine whether sleep quality predicts the risk of future mental health problems, and vice versa.

METHODS

The sleep quality and mental health status of 686 male college students were estimated, and 582 of them were followed up a year later. Subjective sleep quality and mental health problems were measured with the Pittsburgh Sleep Quality Index (PSQI) and the Depression Anxiety Stress Scale-21 (DASS-21), respectively.

RESULTS

Either at baseline or during follow-up, the PSQI global score was positively associated with scores for depression, anxiety, and stress on the DASS-21 (p's < 0.001). Longitudinal analyses revealed that DASS-21 total score increased in line with increased of PSQI global score during the year (p < .001). More importantly, the cross-lagged analysis showed that (i) PSQI global score at baseline was positively related to depression (β = 0.261), anxiety (β = 0.321), and stress (β = 0.311) scores a year later (p's < 0.001) and (ii) depression (β = 0.259), stress (β = 0.245) and anxiety (β = 0.292) scores at baseline were related to PSQI global score a year later (p's < 0.001). Finally, we further found that among those without mental health problems at baseline, poorer baseline sleep quality predicted a higher risk of anxiety symptoms a year later (RR 3.07, 95% CI 1.36-6.97, p = .007).

CONCLUSIONS

These data may suggest a bidirectionally relationship between sleep quality and mental health problems.

A tumor-infiltrating IL23R-expressing CD4+ Treg population represents a safe and potent immunotherapeutic candidate in mice

Interleukin 23 receptor (IL23R) is a signaling protein normally implicated in gut T cell development, but which has also been correlated with poor cancer prognoses. Previous studies have found that interfering with this pathway results in improved cancer outcomes in mice. These studies found that blocking IL23R was more effective than neutralizing IL23, suggesting that an IL23R-expressing cell was responsible for the tumor-protective effects observed in targeting IL23R. Here, we show that Treg-specific targeting of IL23R provides potent tumor immunity that explains previous successes with anti-IL23R therapy in cancer. We show that there is indeed a tumor-infiltrating Treg subset, marked by IL23R expression, that is enriched for markers of potent suppressive activity. Moreover, we find that targeting their IL23R expression is correlated with Treg conversion and increased IFNγ expression on tumor-infiltrating CD8 T cells. Preliminary results suggest that this Treg conversion is associated with enhanced IL12 sensitivity as a result of targeting the IL23R chain. In keeping with the tumor-specific expression pattern of IL23R, we did not find these changes in systemic T cells in the tumor-bearing mice. Ultimately, these Treg-specific IL23R-deleted mice do not display overt autoimmune disease at even advanced ages, suggesting this approach could represent a safe avenue of cancer immunotherapeutic research.

Associations of ambient air pollutant exposure with seminal plasma MDA, sperm mtDNA copy number, and mtDNA integrity

BACKGROUND

Current available evidence regarding the detrimental effects of low-level ambient air pollution on conventional semen parameters is inconclusive. In nonreproductive systems, air pollutant exposure has been demonstrated to induce oxidative stress (OS), which is a crucial mechanism that mediates sperm damage and male infertility. Thus, it may be essential to investigate the effects of air pollution on sperm quality in terms of the perspectives of OS and relative molecular damage.

OBJECTIVES

We assessed the associations of major air pollutant exposure to oxidative stress-mediated alterations in semen, including seminal plasma malondialdehyde (MDA), sperm mtDNA copy number, and integrity.

METHODS

The present study used data gathered from 516 young men participating in the Male Reproductive Health in Chongqing College student (MARCHS) cohort study during the follow-up stage in 2014 (n = 427 on the old campus, which is located in an urban area and has worse air quality, and n = 89 on the new campus, which is not urban and has better air quality). Data regarding major air pollutant exposure during 0-90, 0-9, 10-14 and 70-90 days before each semen examination (corresponding to the entire and three key periods of sperm development, respectively) were collected. The Mann-Whitney U nonparametric test was employed to compare distributions of major air pollutants and to explore differences in MDA, mtDNA copy number, and mtDNA integrity between the two campuses. A linear regression model was used as multivariable analysis to investigate associations of major air pollutant exposure with these biomarkers of oxidative damage to sperm and to adjust for potential confounders.

RESULTS

During all four key periods of sperm development, compared with college students on the new campus, college students on the old campus were exposed to higher levels of PM10, PM2.5, NO₂, and CO, and had higher air quality index (AQI) values, indicating that these participants suffered from worse air quality. The levels of seminal plasma MDA in college students on the old campus were higher than those for the new campus (2.0 nmol/ml; 0.7, 3.6 vs. 1.6 nmol/ml; 0.4, 3.4, p < 0.001) (medians with 5th and 95th percentiles). There were no significant differences in sperm mtDNA copy number and mtDNA integrity between the two campuses. Furthermore, daily average PM10 exposure during 0-90 days before semen ejaculation was found to be significantly and positively associated with seminal plasma MDA level (10.4; 95% CI, 4.4, 16.4) (percentage change per 10-unit increase in air pollutant concentration; same meanings for the results below); daily average SO₂ exposure for 70-90 days and NO₂ exposure for 0-9 days prior to sampling were also positively associated with MDA level (74.7; 95% CI, 32.1, 119 and 11.9; 95% CI, 4.8, 19.0, respectively). AQI for 0-90 days and 70-90 days prior to sampling positively correlated with seminal plasma MDA concentrations (11.4; 95% CI, 4.7, 18.1 and 12.2; 95% CI, 5.3, 19.1, respectively). Additionally, daily average SO₂ exposures for 10-14 and 0-9 days prior to sampling were negatively associated with sperm mtDNA copy number and mtDNA integrity, respectively (-9.0; 95% CI, -16.4, -1.6 and -38.3; 95% CI, -64.1, -11.8, respectively). However, only the correlations between SO₂ exposure and AQI value for 70-90 days prior to sampling and MDA levels remained significant after multiplicity adjustment.

CONCLUSIONS

The results indicate that bad air quality, especially SO₂ exposure during certain periods of sperm development, might be correlated with oxidative damage to sperm. These findings can deepen the understanding of the potential impacts of air pollution on sperm quality.

Strand displacement DNA synthesis by DNA polymerase gp90 exo- of Pseudomonas aeruginosa phage 1

Strand displacement DNA synthesis is essential for DNA replication. Gp90, the sole DNA polymerase of Pseudomonas aeruginosa phage 1, can bypass multiply DNA lesions. However, whether it can perform strand displacement synthesis is still unknown. In this work, we found that gp90 exo^- could perform strand displacement synthesis, albeit its activity and processivity were lower than those of primer extension. Gp90 exo^- itself could not unwind Y-shaped or fork DNA. Tail and gap at DNA fork were necessary for efficient synthesis. High GC content obviously inhibited strand displacement synthesis. Consecutive GC sequence at the entrance of fork showed more inhibition effect on DNA synthesis than that in the downstream DNA fork. The fraction of productive polymerase and DNA complex (A values) was higher for fork than gap; while their average extension rates (k_p values) were similar. However, both A and k_p values were lower than those for the primer/template (P/T) substrate. The binding of gp90 exo^- to fork was tighter than P/T or gap in the absence of dATP. In the presence of dATP to form ternary complex, the binding affinity of gp90 exo^- to P/T or gap was increased compared with that in the binary complex. Abasic site, 8-oxoG, and O⁶-MeG inhibited and even blocked strand displacement synthesis. This work shows that gp90 exo^- could perform strand displacement DNA synthesis at DNA fork, discovering the presence of new functions of PaP1 DNA polymerase in DNA replication and propagation of PaP1.

Epigenetic Inactivation of SOX30 Is Associated with Male Infertility and Offers a Therapy Target for Non-obstructive Azoospermia

Non-obstructive azoospermia (NOA) is the most severe form of male infertility. However, the etiology of NOA is largely unknown, resulting in a lack of clinical treatments. Here, we performed a comparative genome-wide profiling of DNA methylation and identified SOX30 as the most notably hyper-methylated gene at promoter in testicular tissues from NOA patients. This hyper-methylation at promoter of SOX30 directly causes its silencing of expression in NOA. The reduced levels of SOX30 expression are correlated with severity of NOA disease. Deletion of Sox30 in mice uniquely impairs testis development and spermatogenesis with complete absence of spermatozoa in testes leading to male infertility, but does not influence ovary development and female fertility. The pathology and testicular size of Sox30 null mice highly simulate those of NOA patients. Re-expression of Sox30 in Sox30 null mice at adult age reverses the pathological damage of testis and restores the spermatogenesis. The re-presented spermatozoa after re-expression of Sox30 in Sox30 null mice have the ability to start a pregnancy. Moreover, the male offspring of Sox30 re-expression Sox30 null mice still can father children, and these male offspring and their children can live normally more than 1 year without significant difference of physical appearance compared with wild-type mice. In summary, methylated inactivation of SOX30 uniquely impairs spermatogenesis, probably causing NOA disease, and re-expression of SOX30 can successfully restore the spermatogenesis and actual fertility. This study advances our understanding of the pathogenesis of NOA, offering a promising therapy target for NOA disease.

Pharmacological Characteristics of Anxiolytics on Acetylcholine-Induced Contractions in Rat Detrusor Smooth Muscle

INTRODUCTION

Benzodiazepine anxiolytics are believed to cause urination disorders due to their anticholinergic effects.

OBJECTIVE

This study was carried out to investigate the potential inhibitory effects of 15 clinically available anxiolytics in Japan on acetylcholine (ACh)-induced contractions in rat detrusor smooth muscle (DSM) to predict whether these anxiolytics could induce urination disorders.

METHODS

-Effects of anxiolytics on contractions induced by ACh and 80 mmol/L KCl solution in rat DSM and effects of anxiolytics on specific binding of [N-methyl-3H]scopolamine ([3H]NMS) in mouse cerebral cortex were investigated.

RESULTS AND CONCLUSIONS

ACh-induced contractions in rat DSM were inhibited by clotiazepam and diazepam (benzodiazepine anxiolytics) at concentrations that were clinically relevant. These contractions were also significantly inhibited by paroxetine, escitalopram (selective serotonin reuptake inhibitors -[SSRIs]), and hydroxyzine (a histamine H1 receptor antagonist), albeit at concentrations that substantially exceeded clinically achievable blood levels. At a concentration of 10-5 mol/L, paroxetine, escitalopram, and hydroxyzine inhibited 80 mmol/L high-KCl solution-induced rat DSM contractions but not clotiazepam and diazepam. Paroxetine, escitalopram, and hydroxyzine also inhibited specific binding of [3H]NMS in mouse cerebral cortex but clotiazepam and diazepam did not. In contrast to the effects of the abovementioned anxiolytics, ACh-induced contractions were not significantly affected by tofisopam, alprazolam, lorazepam, bromazepam, oxazolam, chlordiazepoxide, clonazepam, ethyl loflazepate (benzodiazepine anxiolytics), fluvoxamine (an SSRI), or tandospirone (a serotonin 5-HT1A receptor agonist). These findings suggest that most clinically used anxiolytics are not likely to result in anticholinergic-induced urination disorders within their clinically achievable blood concentration ranges. However, clotiazepam and diazepam may induce urination disorders within their clinical dose ranges via nonanticholinergic inhibition of DSM contractility.

Tac2-N acts as a novel oncogene and promotes tumor metastasis via activation of NF-κB signaling in lung cancer

BACKGROUND

High rates of recurrence and metastasis are the major cause of the poor outcomes for patients with lung cancer. In previous research, we have demonstrated that Tac2-N promotes tumor growth by suppressing p53 signaling in lung cancer. Beyond that, other biological functions and clinical significance of Tac2-N in lung cancer progression are still unknown.

METHODS

Tissue microarrays of 272 lung cancer patients were constructed to assess the association of Tac2-N expression and prognosis of lung cancer patients with different clinical stages. The protein expression of Tac2-N in metastatic and non-metastatic specimens were detected by IHC. In vitro migration and invasion and in vivo nude mice metastasis model were used to evaluate the effect of Tac2-N ectopic expression on metastasis capability of lung cancer cells. The downstream signaling pathway of Tac2-N was explored using luciferase reporter assays and WB.

RESULTS

The expression of Tac2-N was associated with advanced stages, but not with early stages (P = 0.513). Tac2-N expression is sharply overexpressed in metastatic tumors compared with non-metastatic tumors. In vitro and in vivo assays suggested that Tac2-N facilitated migration and invasion of lung cancer cells in vitro and promoted tumor metastasis in vivo. Mechanistically, Tac2-N increased the degradation of IκB by promoting its phosphorylation, and subsequently activated NF-κB activity by facilitating the nuclear translocation of NF-κB and stimulating the transcription of targets, MMP7 and MMP9. Notably, the C2B domain of Tac2-N was crucial for Tac2-N to activate NF-κB signal. Blockage of NF-κB by shRNA or inhibitor attenuates the function of Tac2-N in the promotion of metastasis.

CONCLUSIONS

Our study provided proof of principle to show that Tac2-N serves as a novel oncogene gene and plays an important role in the progression and metastasis of lung cancer.

Author Correction: Identification of TC2N as a novel promising suppressor of PI3K-AKT signaling in breast cancer

After publication of this article, it came to the attention of the authors that their names had been reordered. Professor. Jia Cao and Prof. Jin-yi Liu are the co-corresponding authors, and Prof. Jin-yi Liu should be the last author.

Identification of TC2N as a novel promising suppressor of PI3K-AKT signaling in breast cancer

Although TC2N has proven to be an oncogene in lung cancer, its biological function and molecular mechanisms in other cancer still remains unclear. Here, we investigate in breast cancer that TC2N expression is sharply overexpressed in breast cancer specimens compared with normal breast specimens, and the low TC2N expression was associated with advanced stage, lymphatic metastasis, larger tumors and shorter survival time. Upregulation of TC2N significantly restrains breast cancer cell proliferation in vitro and tumor growth in vivo. Mechanistically, TC2N blocks AKT signaling in a PI3K dependent and independent way through weakening the interaction between ALK and p55γ or inhibiting the binding of EBP1 and AKT. To sum up, these results unmask an ambivalent role of TC2N in cancer, providing a promising inhibitor for PI3K-AKT signaling.

Social support modifies an association between work stress and semen quality: Results from 384 Chinese male workers

OBJECTIVE

Psychosocial factors have been associated with a decline of the quality of semen. The study was aimed at (i) estimating the association between work stress and semen quality and (ii) exploring the moderating effect of social support in semen parameters among Chinese male workers.

METHODS

Data were obtained from 384 adult male workers recruited from April 2014 to December 2015 in Chongqing, China. Participants completed a questionnaire assessing demographic and life-style factors. Work stress and social support was measured by the Chinese version of a 22-item Job Content Questionnaire (JCQ). They underwent a physical examination and provided a semen sample.

RESULTS

Subjects with high work stress were associated with a higher risk of being classified below WHO's thresholds for "normal," defined by sperm concentration (OR 2.14, 95% CI 1.24-3.68, p = .006) or total sperm count (OR 1.95, 95% CI 1.13-3.36, p = .02) criteria than subjects with low work stress were. However, these adverse associations were not observed among subjects with high social support (p = .80 for sperm concentration, and p = .39 for total sperm count). Interaction effects between social support and work stress on sperm concentration (p = .002) and total sperm count (p = .02) were detected.

CONCLUSION

Work stress is associated with lower levels of semen quality. Social support attenuates the negative association between work stress and semen quality, which may have implications for reproductive health.

Evaluation of Antidepressant Effects on Recovery of Electrical Field Stimulation-Induced Contractions that have been Suppressed by Clonidine in Isolated Rat Vas Deferens

<b><i>Background:</i></b> A report examining whether clinically available antidepressants increase urethral smooth muscle contraction via antagonistic effects on the α₂-adrenoceptor (α₂-AR) is lacking. <b><i>Objectives:</i></b> The present study was performed to evaluate the potential of clinically available antidepressants to reverse α₂-AR-mediated contractile inhibition in rat vas deferens, in order to predict whether they can induce voiding impairment. <b><i>Method:</i></b> The effects of 18 antidepressants of different classes on electrical field stimulation (EFS)-induced contractions suppressed by 10^–8 mol/L clonidine (a selective α₂-AR agonist) in isolated rat vas deferens were investigated and related to their respective clinical blood concentrations. <b><i>Results:</i></b> The EFS-induced contractions suppressed by clonidine were recovered by amitriptyline (a tricyclic antidepressant), mirtazapine (a noradrenergic and specific serotonergic antidepressant), and trazodone (a serotonin 5-HT_2A receptor antagonist) at concentrations close to the clinical blood levels. EFS-induced contractions were also recovered by trimipramine, clomipramine (tricyclic antidepressants), mianserin (a tetracyclic antidepressant), sertraline (a selective serotonin reuptake inhibitor [SSRI]), and sulpiride (a dopamine D₂-receptor antagonist), albeit at concentrations that substantially exceeded their clinically-achievable blood levels. EFS-induced contractions were not significantly affected by imipramine, nortriptyline, amoxapine (tricyclic antidepressants), maprotiline (a tetracyclic antidepressant), fluvoxamine, paroxetine, escitalopram (SSRIs), milnacipran, duloxetine (serotonin and noradrenaline reuptake inhibitors), and aripiprazole (a dopamine partial agonist). Conclusions: These findings suggest that amitriptyline, mirtazapine, and trazodone induce voiding impairment caused by increased urethral resistance by enhancing sympathetic nerve activities attributed to α₂-AR antagonism.