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

OBJECTIVE: To explore the influence of oligospermia (OS) on the detection of sperm DNA fragmentation index (DFI) by fluorescence method based on artificial intelligence (AI) recognition and flow cytometry-based sperm chromatin structure assay (SCSA). METHODS: We collected semen samples from 201 males, including 50 azoospermia (AS) patients as negative controls, 90 OS patients (sperm concentration >0×10⁶/ml and <15×10⁶/ml), and 61 normal men (sperm concentration ≥15×10⁶/ml). Then we subdivided the OS patients into a mild OS (sperm concentration ≥10×10⁶/ml and <15×10⁶/ml), a moderate OS (sperm concentration ≥5×10⁶/ml and <10×10⁶/ml) and a severe/extremely severe OS group (sperm concentration >0×10⁶/ml and <5×10⁶/ml), with 30 cases in each group, and compared the results of DFI detection between the AI fluorescence method and traditional flow cytometry. RESULTS: The DFI value detected by AI fluorescence method showed statistically significant difference from that detected by flow cytometry in the AS, moderate OS and severe/extremely severe OS groups (P<0.01), the former even lower than the latter, but not in the normal control and the mild OS groups (P > 0.05). In the AS group, a dramatically lower rate of non-0 results was achieved by AI fluorescence method than by flow cytometry (8% vs 100%, P<0.01). The DFI values detected by AI fluorescence method exhibited a good linear correlation to those obtained by flow cytometry in the normal control and mild OS groups (R2 = 0.7470; R2 = 0.7180), but a poor linear correlation in the OS full-sample, moderate OS and severe/extremely severe OS groups (R2 = 0.3092; R2 = 0.3558; R2 = 0.2147). CONCLUSION The AI fluorescence method has a higher specificity and is more suitable than flow cytometry for detection of sperm DFI in OS patients. The DFI values obtained by the two methods are consistent with sperm concentration ≥10×10⁶/ml, but the accuracy of the results of detection may be affected with sperm concentration >0×10⁶/ml and <10×10⁶/ml.
Humans ; Male ; Flow Cytometry/methods* ; Oligospermia/genetics* ; Artificial Intelligence ; Spermatozoa ; Adult ; DNA Fragmentation ; Case-Control Studies ; Fluorescence

OBJECTIVE: By analyzing the differential miRNA in seminal plasma between individuals with normal and abnormal sperm DNA fragmentation index（DFI）, we aim to identify miRNA that may impact sperm DNA integrity and target genes, and attempt to analyze their potential mechanisms of action. METHODS: A total of 161 study subjects were collected and divided into normal control group, DFI-medium group and DFI-abnormal group based on the DFI detection values. Differential miRNA were identified through miRNA chip analysis. Through bioinformatics analysis and target gene prediction, miRNA related to DFI and specific target genes were identified. The relative expression levels of differential miRNA and target genes in each group were compared to explore the impact of their differential expression on DFI. RESULTS: Through miRNA chip analysis, a total of 11 differential miRNA were detected. Bioinformatics analysis suggested that miR-26a-5p may be associated with reduced sperm DNA integrity. And gene prediction indicated that PTEN was a specific target gene of miR-26a-5p. Compared to the normal control group, the relative expression levels of miR-26a-5p in both the DFI-medium group and the DFI-abnormal group showed a decrease, while the relative expression levels of PTEN showed an increase. The relative expression levels of miR-26a-5p in all groups were negatively correlated with DFI values, while the relative expression levels of PTEN showed a positive correlation with DFI values in the DFI-medium group and the DFI-abnormal group. The AUC of miR-26a-5p in the DFI-medium group was 0.740 (P<0.05), with a sensitivity of 73.6% and a specificity of 71.5%; the AUC of PTEN was 0.797 (P<0.05), with a sensitivity of 76.5% and a specificity of 78.4%. In the DFI-abnormal group, the AUC of miR-26a-5p was 0.848 (P<0.05), with a sensitivity of 81.3% and a specificity of 78.1%. While the AUC of PTEN was 0.763 (P<0.05), with a sensitivity of 77.2% and a specificity of 80.2%. CONCLUSION miR-26a-5p affects the integrity of sperm DNA by regulating the expression of PTEN negatively. The relative expression levels of seminal plasma miR-26a-5p and PTEN have good diagnostic value for sperm DNA integrity damage, which can help in the etiological diagnosis and prognosis analysis of abnormal DFI. This provides a diagnostic and treatment approach for the study and diagnosis of DFI abnormalities without clear etiology.
Male ; Humans ; MicroRNAs/genetics* ; PTEN Phosphohydrolase/genetics* ; Spermatozoa ; Semen/metabolism* ; DNA Fragmentation

To investigate the relationship between male semen parameters and sperm DNA fragment index with age. Adopt cross-sectional sampling survey design, 3 203 male patients who visited the Department of Reproductive Andrology in the Third Affiliated Hospital of Zhengzhou University from January 2019 to June 2021 were selected as subjects. Age range is 18-57 years, with the median age of 30 years. Through quartile regression analysis, the correlation between age and different male semen parameters and DNA fragment index (DFI) was presented. The study population was divided into ≤30 years old group and >30 years old group, and the correlation between age and semen volume, sperm concentration, total sperm count, progressive motility, total motility, percentage of normal sperm and DFI level were compared and analyzed. The results showed that there were significant differences in progressive motility, total motility and DFI level among different age groups (χ²=-4.608, -4.604, -7.719,P all <0.05), but there was no significant difference in semen volume, sperm concentration, total sperm count and percentage of normal sperm (χ²=-1.712, -1.203, -0.149, -0.175,P all >0.05). In the>30 years old age group, there was a very weak negative correlation between male age and semen volume, progressive motility and total motility (r=-0.137, -0.101 and -0.056, P all <0.05). There was a very weak positive correlation between male age and sperm concentration and sperm DFI level (r=0.061, 0.190, P all <0.05), while there was no correlation between male age and total sperm count and percentage of normal sperm (r=-0.018, -0.016,P all >0.05). In conclusion, with the increase of age, especially after the age of 30, semen volume, progressive motility and total motility decreased, while sperm concentration and DFI level increased, and semen quality decreased.
Humans ; Male ; Adult ; Adolescent ; Young Adult ; Middle Aged ; Semen ; Semen Analysis ; Cross-Sectional Studies ; Infertility, Male/genetics* ; Sperm Motility ; DNA Fragmentation ; Spermatozoa ; Sperm Count ; DNA

To investigate the relationship between male semen parameters and sperm DNA fragment index with age. Adopt cross-sectional sampling survey design, 3 203 male patients who visited the Department of Reproductive Andrology in the Third Affiliated Hospital of Zhengzhou University from January 2019 to June 2021 were selected as subjects. Age range is 18-57 years, with the median age of 30 years. Through quartile regression analysis, the correlation between age and different male semen parameters and DNA fragment index (DFI) was presented. The study population was divided into ≤30 years old group and >30 years old group, and the correlation between age and semen volume, sperm concentration, total sperm count, progressive motility, total motility, percentage of normal sperm and DFI level were compared and analyzed. The results showed that there were significant differences in progressive motility, total motility and DFI level among different age groups (χ²=-4.608, -4.604, -7.719,P all <0.05), but there was no significant difference in semen volume, sperm concentration, total sperm count and percentage of normal sperm (χ²=-1.712, -1.203, -0.149, -0.175,P all >0.05). In the>30 years old age group, there was a very weak negative correlation between male age and semen volume, progressive motility and total motility (r=-0.137, -0.101 and -0.056, P all <0.05). There was a very weak positive correlation between male age and sperm concentration and sperm DFI level (r=0.061, 0.190, P all <0.05), while there was no correlation between male age and total sperm count and percentage of normal sperm (r=-0.018, -0.016,P all >0.05). In conclusion, with the increase of age, especially after the age of 30, semen volume, progressive motility and total motility decreased, while sperm concentration and DFI level increased, and semen quality decreased.
Humans ; Male ; Adult ; Adolescent ; Young Adult ; Middle Aged ; Semen ; Semen Analysis ; Cross-Sectional Studies ; Infertility, Male/genetics* ; Sperm Motility ; DNA Fragmentation ; Spermatozoa ; Sperm Count ; DNA

Semen analysis has long been used to evaluate male fertility. Recently, several sperm function tests have been developed. Of those, the sperm DNA fragmentation index (DFI), which describes the status of the sperm DNA, is thought to be a suitable parameter for evaluating male fertility. However, there have been no large-scale studies on the sperm DFI of Japanese men. Therefore, we investigated the feasibility of using an in-house flow cytometry-based sperm DFI analysis based on the sperm DNA fragmentation test of sperm chromatin structure assay (SCSA) to assess male fertility in Japan. This study enrolled 743 infertile and 20 fertile Japanese men. To evaluate reproducibility, inter- and intraobserver precision was analyzed. A receiver operating characteristic curve analysis was used to set a cutoff value for the sperm DFI to identify men who could father children by timed intercourse or intrauterine insemination. The variability of the sperm DFI among fertile volunteers was determined. The relationship between semen parameters and the sperm DFI was assessed by Spearman's rho test. A precision analysis revealed good reproducibility of the sperm DFI. The cutoff value of sperm DNA fragmentation in infertile men was 24.0%. Semen volume had no relationship with the sperm DFI. Sperm concentration, sperm motility, total motile sperm count, and percentage of normal-shaped sperm were significantly and negatively correlated with the sperm DFI. The median sperm DFI was smaller in fertile volunteers (7.7%) than that in infertile men (19.4%). Sperm DNA fragmentation analysis can be used to assess sperm functions that cannot be evaluated by ordinary semen analysis.
Child ; Chromatin ; DNA Fragmentation ; Flow Cytometry ; Humans ; Infertility, Male/genetics* ; Japan ; Male ; Reproducibility of Results ; Sperm Motility ; Spermatozoa

ObjectiveTo explore the correlation of the sperm DNA fragmentation index (DFI) with age, sperm concentration and sperm motility in infertile men.

METHODSWe collected semen samples from 531 infertile males in our hospital from January 2016 to June 2017. We determined the semen parameters using the computer-assisted semen analysis system, measured the sperm DFI by sperm chromatin structure assay, and analyzed the correlation of the sperm DFI with the age, sperm concentration and sperm motility of the patients.

RESULTSWith the increase of age, the infertile males showed a significantly decreased proportion of the sperm with a DFI ≤15% and elevated proportion of the sperm with a DFI ≥25%, with a positive correlation between age and sperm DFI (r = 0.653, P < 0.01). With the increase of sperm concentration and motility, however, the proportion of the sperm with a DFI ≤15% was remarkably increased while that of the sperm with 15%

CONCLUSIONSThe sperm DFI is significantly correlated with age, sperm concentration and sperm motility, and therefore can be used as an important index for the evaluation of semen quality. A comprehensive analysis of the sperm DFI and semen parameters may contribute to an accurate assessment of male fertility.

Age Factors ; Body Fluids ; DNA Fragmentation ; Humans ; Infertility, Male ; genetics ; Male ; Semen ; chemistry ; Semen Analysis ; Sperm Count ; Sperm Motility ; Spermatozoa

Objective: Sperm DNA fragmentation (SDF) is widely used to predict male infertility and the methods of detecting SDF are varied. This study aimed to compare two methods of SDF detection and investigate the correlation between SDF and sperm quality. METHODS: Using sperm chromatin structure assay (SCSA) and sperm chromatin dispersion test (SCD), we detected SDF in 108 semen samples collected in the Center of Reproduction and Genetics of Suzhou Municipal Hospital. We compared the results of the two methods and analyzed the correlations of SDF routine semen parameters, sperm morphology and the age of the patients. RESULTS: A significant consistency was found in the SDF index (DFI) between the two methods (P<0.01). The DFI was correlated negatively with sperm motility, the percentage of progressively motile sperm, and that of morphologically normal sperm (P <0.01), but positively with the teratozoospermia index (P <0.01 in SCSA and P <0.05 in SCD). The DFI measured by SCSA showed a significantly positive correlation with the patients' age (P <0.01), but not that obtained by SCD. CONCLUSIONS The results of both SCSA and SCD play an important role in predicting sperm quality. As a clinical index, the DFI has a predictive value for male infertility. However, the results of different detecting methods vary widely, which calls for further studies on their standardization.
Chromatin ; genetics ; physiology ; DNA Fragmentation ; Humans ; Infertility, Male ; diagnosis ; Male ; Semen ; physiology ; Semen Analysis ; Sperm Motility ; Spermatozoa ; physiology ; ultrastructure

Objective: To study the correlation of the gene expressions of Chk1 and Chk2 with sperm concentration and motility. METHODS: According to sperm concentration and motility (percentage of progressively motile sperm), we divided 80 semen samples into four groups of equal number: normal control, oligozoospermia (OS), asthenospermia (AS), and oligoasthenozoospermia (OAS). We detected the sperm DNA fragmentation index (DFI) and viability and determined the expressions of Chk1 and Chk2 in the sperm by RT-PCR and Western blot. RESULTS: Statistically significant differences were not found in sperm DFI among the control, OS, AS, and OAS groups (21.24±6.93, 19.67±7.64, 21.52±6.92, and 19.28±11.55, P>0.05), but observed in sperm concentration, progressive motility, and viability between the DFI >30% and DFI ≤30% groups (P<0.01). Compared with the normal control, sperm viability was remarkably decreased in the OS, AS, and OAS groups (［83.48±9.87］% vs ［63.86±9.16］%, ［50.45±16.99］%, and ［39.21±15.74］%, P<0.05). RT-PCR showed remarkable differences among the control, OS, AS, and OAS groups in the relative expression level of Chk1 mRNA (0.73±0.22, 0.62±0.14, 1.03±0.39, and 0.92±0.071, P<0.01), which was correlated positively with sperm concentration (b = 80.661, P<0.01) but negatively with sperm motility (b = －19.275, P < 0.01), as well as in that of Chk2 mRNA (0.66±0.30, 0.27±0.09, 0.59±0.19, and 0.42 ± 0.11, P<0.01), which was correlated negatively with sperm concentration (b = －90.809, P<0.01) but positively with sperm motility (b = 27.507, P <0.01). The relative expression levels of the Chk1 protein were significantly different among the four groups (0.63±0.05, 0.42±0.03, 1.13±0.08, and 0.87±0.07, P<0.01), which was correlated positively with sperm concentration (b = 55.74, P<0.01) but negatively with sperm motility (b =－22.649, P<0.01), and so were those of the Chk2 protein (1.23±0.36, 0.37±0.16, 0.87±0.08, and 0.68±0.12, P<0.01), which was correlated negatively with sperm concentration (b =－53.001, P<0.01) but positively with sperm motility (b = 16.676, P < 0.01). CONCLUSIONS Chk1 and Chk2 are significantly expressed in human sperm. In case of sperm DNA damage, up-regulated Chk1 expression may enhance sperm apoptosis and lead to asthenospermia, while increased Chk2 expression may inhibit spermatogenesis and result in oligospermia.
Apoptosis ; Asthenozoospermia ; genetics ; Checkpoint Kinase 1 ; genetics ; metabolism ; Checkpoint Kinase 2 ; genetics ; metabolism ; DNA Damage ; DNA Fragmentation ; Gene Expression ; Humans ; Male ; Oligospermia ; genetics ; Semen Analysis ; Sperm Count ; Sperm Motility ; genetics ; Spermatozoa ; physiology

Objective: To explore the protective effect of Tongjingling (TJL) against sperm DNA damage and oxidative stress in the rat model of experimental varicocele (EVC). METHODS: We randomly divided 75 Wistar male rats into five groups of equal number: sham operation, EVC model, high-dose TJL, mid-dose TJL, and low-dose TJL. The EVC model was established in the rats by partial ligation of the left renal vein, followed by 8 weeks of medication from the 4th week after modeling. Then we observed the general status of the rats, detected the sperm DNA fragmentation index (DFI) in the epididymis by sperm chromatin structure assay (SCSA), and measured the content of hydroperoxide (H2O2) and the activities of catalase (CAT) and superoxide dismutase (SOD) in the testis by colorimetry. RESULTS: Compared with the sham operation group, the EVC models showed significantly increased sperm DFI in the epididymis (P <0.01) and elevated level of H2O2 and activities of CAT and SOD in the testis (P <0.01). In comparison with the EVC models, the rats of the TJL groups exhibited remarkably reduced sperm DFI and H2O2 content, but increased activities of SOD and CAT. CONCLUSIONS TJL can improve sperm DNA integrity by increasing the activities of SOD and CAT and reducing the H2O2 level and hence oxidative stress in the testis tissue.
Animals ; Catalase ; analysis ; DNA ; drug effects ; DNA Fragmentation ; Drugs, Chinese Herbal ; pharmacology ; Epididymis ; chemistry ; Humans ; Hydrogen Peroxide ; analysis ; Ligation ; Male ; Oxidative Stress ; Random Allocation ; Rats ; Rats, Wistar ; Spermatozoa ; Superoxide Dismutase ; analysis ; Testis ; chemistry ; drug effects ; Varicocele ; etiology ; genetics ; metabolism