LY294002, a PI3K pathway inhibitor,prevents leptin‐induced adverse effects on spermatozoa in Sprague‐Dawley rats

This study examined the effects of PI3K and AMPK signalling pathway inhibitors on leptin‐induced adverse effects on rat spermatozoa. Sprague‐Dawley rats, aged 14–16 weeks, were randomised into control, leptin‐, leptin + dorsomorphin (AMPK inhibitor)‐, and leptin+LY294002 (PI3K inhibitor)‐treated groups with six rats per group. Leptin was given once daily for 14 days via the intraperitoneal (i.p.) route at a dose of 60 ug kg^?1 body weight. Rats in the leptin and inhibitor‐treated groups received concurrently either dorsomorphin (5 mg kg^?1 day^?1) or LY294002 (1.2 mg kg^?1 day^?1) i.p. for 14 days. Controls received 0.1 ml of normal saline. Upon completion, sperm count, sperm morphology, seminiferous tubular epithelial height (STEH), seminiferous tubular diameter (STD), 8‐hydroxy‐2‐deoxyguanosine (8‐OHdG) and phospho‐Akt/total Akt ratio were estimated. Data were analysed using ANOVA. Sperm count, STEH and STD were significantly lower, while the percentage of spermatozoa with abnormal morphology and the level of 8‐OHdG were significantly higher in rats treated with leptin and leptin + dorsomorphin when compared to those in controls and LY294002‐treated rats. Testicular phospho‐Akt/total Akt ratio was significantly higher in leptin and leptin + LY294002‐treated rats. In conclusion, LY294002 prevents leptin‐induced changes in rat sperm parameters, suggesting the potential role of the PI3K signalling pathway in the adverse effects of leptin on sperm parameters.     

Adverse effects of leptin on histone‐to‐protamine transition during spermatogenesis are prevented by melatonin in Sprague‐Dawley rats

This study examines the effect of melatonin on leptin‐induced changes in transition of histone to protamine in adult rats during spermatogenesis. Twelve‐week‐old Sprague‐Dawley rats were randomised into control, leptin‐, leptin–melatonin‐10‐, leptin–melatonin‐20‐ and melatonin‐10‐treated groups with six rats per group. Leptin was given via intraperitoneal injections (i.p.) daily for 42 days (60 μg/kg body weight). Rats in the leptin‐ and melatonin‐treated groups were given either 10 or 20 mg day^?1 kg^?1 body weight of leptin in drinking water. Melatonin‐10‐treated group received only 10 mg of melatonin day^?1 kg^?1 body weight in drinking water for 42 days. Control rats received 0.1 ml of 0.9% saline. Upon completion of the treatment, sperm count, morphology and histone‐to‐protamine ratio were estimated. Gene expression of HAT, HDAC1, HDAC2, H2B, H2A, H1, PRM1, PRM2, TNP1 and TNP2 was determined. Data were analysed using ANOVA. Sperm count was significantly lower, whereas the fraction of spermatozoa with abnormal morphology, the ratio of histone‐to‐protamine transition and the expressions of HAT, HDAC1, HDAC2, H2B, H2A, H1, PRM1 were significantly higher in leptin‐treated rats than those in controls or melatonin‐treated rats. It appears that exogenous leptin administration adversely affects histone‐to‐protamine transition, which is prevented by concurrent administration of melatonin.     

The association of seminal leucocytes,interleukin‐6 and interleukin‐8 with sperm DNA fragmentation: A prospective study

The effect of seminal leucocytes on sperm DNA integrity has been discussed controversially in literatures. Moreover, the studies investigating the in vivo effect of pro‐inflammatory cytokines interleukin‐6 and interleukin‐8 on sperm DNA fragmentation are scarce and inconsistent. The association of standard sperm parameters with sperm DNA fragmentation is also a matter of ongoing discussion. Hence, the aims of this study were, first, to evaluate the effect of seminal leucocytes, interleukin‐6 and interleukin‐8 on sperm DNA integrity and, second, to examine whether standard semen parameters are associated with sperm DNA fragmentation. Seminal leucocytes, interleukin‐6, interleukin‐8 and standard semen parameters, including total sperm number, sperm concentration, progressive motility, nonprogressive motility, immotility and normal morphology, were determined in 134 consecutive men. The concentrations of seminal leucocytes, interleukin‐6 and interleukin‐8, did not correlate with sperm DNA fragmentation. In contrast, total sperm number, sperm concentration, progressive motility, nonprogressive motility and normal morphology exhibited significant inverse correlations with sperm DNA fragmentation. Immotile spermatozoa were directly correlated with sperm DNA fragmentation. In conclusion, seminal leucocytes, interleukin‐6 and interleukin‐8, are not associated with sperm DNA fragmentation. Poor standard semen parameters are significantly related to the high levels of sperm DNA fragmentation.     

The reversibility of sperm quality after discontinuing nandrolone decanoate in adult male rats

Aim： To investigate the reversibility of the effect of nandrolone decanoate （ND） on sperm parameters after discontinuing the drug. Methods： Three groups of rats received peanut oil （control）, low and high doses of ND for 14 weeks, respectively. Each group was divided into subgroups A and B, in which rats were killed 14 and 28 weeks after initiating the injection, respectively. Results： Sperm count and motile sperm fraction were decreased in the subgroups A and B that received low and high doses of ND in comparison with the controls A and B, respectively. The sperm count and motile sperm fraction increased in the subgroups B that received low and high doses of ND in comparison with their corresponding subgroups A. The number of normal morphology sperm was decreased significantly in subgroups A receiving low and high doses of ND in comparison with the control subgroup A. However, this parameter was not decreased in subgroups B receiving low and high doses in comparison with the control subgroup B. The normal sperm morphology did not show any significant differences in the subgroups B in comparison with their corresponding subgroups A. Conclusion： The 14-week injection of low and high doses of ND decreases sperm quality and quantity in rats. These parameters were improved after discontinuing ND, but not recovered completely even when they are left untreated for 14 weeks.     

Comparison of sperm morphology and nuclear sperm quality in SPATA16‐ and DPY19L2‐mutated globozoospermic patients

The aim of this study was to compare the sperm morphology and nuclear sperm quality (sperm aneuploidy and DNA fragmentation) in two groups of globozoospermic patients: DPY19L2‐mutated patients (n = 6) and SPATA16‐mutated patients (n = 2). Results for these two groups were also compared to a group of fertile men (n = 25). Fluorescence in situ hybridisation was performed for chromosomes X, Y and 18. Sperm DNA fragmentation was evaluated by TUNEL assay. Sanger sequencing was performed for mutations screening of DPY19L2 and SPATA16 genes. Sperm analysis revealed a classic phenotype of total globozoospermia in DPY19L2‐mutated group and a particular phenotype characterised by a predominance of double/multiple round‐headed (39.00 ± 4.2%) and multi‐tailed spermatozoa (26.00 ± 16.97%) in SPATA16‐mutated group. FISH analysis showed a significantly higher aneuploidy rate in globozoospermic patients compared to controls (p < 0.05), and a higher rate was observed in SPATA16‐mutated group compared to DPY19L2‐mutated group (p < 0.05). DNA fragmentation index was significantly higher in globozoospermic men compared to controls (p < 0.001), and there is no statistically significant difference between the two globozoospermic groups. We showed that SPATA16 defects could be associated with an abnormal meiosis leading to a particular morphological sperm defect of double/multiple round‐headed and multi‐flagella and a higher sperm aneuploidy rate than in case of DPY19L2‐defects in classic globozoospermia.     

L-肉碱对糖尿病大鼠生精细胞凋亡及附睾精子数量和活动率的影响

目的:探讨L-肉碱(LC)对糖尿病(DM)大鼠生精细胞凋亡及附睾精子数量和活动率的影响。方法:24只雄性SD大鼠随机均分为3组,一组作为对照组,剩余两组分别注射链脲佐菌素(STZ,65 mg/kg)建立DM模型。建模成功后,各组大鼠分别给予如下灌胃剂量:对照组:生理盐水;DM模型组:生理盐水;LC组:300 mg/kgLC溶液,连续灌胃6周。末次给药24 h后,麻醉处死所有大鼠,分别进行附睾精子计数并检测精子活动率,流式细胞术检测各组大鼠睾丸生精细胞凋亡情况。结果:用LC治疗后的大鼠附睾头、尾精子活动率(%)分别为53.7±1.8和60.3±1.6,显著高于DM模型大鼠(分别为32.2±2.0和40.5±1.4,P<0.05),但低于对照组大鼠精子活动率63.1±2.4和68.9±1.3。与对照组附睾尾精子相对计数[(37.8±1.1)×106/100 mg]相比,DM组显著减少[(25.5±1.1)×106/100 mg],且具有统计学差异(P<0.05);LC治疗后大鼠附睾尾精子相对计数[(32.0±1.5)×106/100 mg]比DM组显著增加(P<0.05),但仍低于对照组。与对照组生精细胞凋亡率[(3.7±1.3)%]相比,DM组生精细胞凋亡率[(52.5±4.4)%]显著上升(P<0.05);经LC治疗后,LC组大鼠生精细胞凋亡率为(35.3±3.5)%,比DM组显著降低(P<0.05),但仍显著高于对照组。结论:LC(300 mg/kg)灌胃DM大鼠6周,可以减少DM大鼠生精细胞凋亡,增加附睾精子数量,提高精子活动率。     

Impact of cigarette‐smoking on sperm DNA methylation and its effect on sperm parameters

DNA methylation is an epigenetic modification of the genome. The purpose of this study was to determine the influence of cigarette‐smoking on sperm DNA methylation from a genomewide survey of sperm samples and to ascertain its effect on sperm parameters. Twenty‐eight sperm DNA samples (from 14 fertile smokers as a case study and 14 proven fertile nonsmokers as controls) were subjected to Infinium 450K BeadChip arrays to identify the changes in the DNA methylation level between the two groups. Then, deep bisulphite sequencing was used to validate five CpGs on 78 samples. The results from the Infinium 450K found that only 11 CpGs showed a significant difference in DNA methylation between the case and the control groups. Five CpGs of the eleven (cg00648582, cg0932376, cg19169023, cg23841288 and cg27391564) underwent deep bisulphite sequencing where cg00648582, related to the PGAM5 gene, and the cg23841288 CpGs, related to the PTPRN2 gene amplicons, showed a significant increase in their DNA methylation level in more than one CpG in the case group. In contrast, a significant decrease was found at cg19169023 and at its various neighbouring CpGs in the TYRO3 gene‐related amplicons. Furthermore, this study demonstrated a significant correlation between the variation in sperm DNA methylation level and standard sperm parameters in the case group.     

Influence of extended incubation time on Human sperm chromatin condensation,sperm DNA strand breaks and their effect on fertilisation rate

The purpose of this study was to determine influence of extended incubation time on sperm chromatin condensation and DNA strand breaks and their effect on fertilisation rate. Forty couples undergoing ICSI therapy were included. Semen was prepared by PureSperm gradient centrifugation and divided into two parts. The first part (G1) was used immediately for ICSI, whereas the second part (G2) was kept in the incubator at 37°C, 5% and 90% Humidity for 5 hr, and thereafter, the capacitated spermatozoa were used for ICSI. The TUNEL test and chromomycin CMA3 were used to evaluate the DNA strand breaks and chromatin condensation respectively. The percentage of condensed chromatin was 73.92 ± 12.70 in the group 1 and 81.13 ± 10.31% in group 2 (p = .001). However, the double‐strand breaks were 11.15 ± 8.67% in G.1 and 16.30 ± 11.12% in G.2. (p = .001). Fertilisation rate in the (Group 1) was 62.45% and 69.17% in (Group 2). There was a positive correlation between condensed chromatin and fertilisation rate (r = 0.846, p = .001) and a negative correlation with DNA double‐strand breaks (r = ?0.802; p = .001). In conclusion, the prolonged sperm incubation (5 hr) leads to a higher chromatin condensation and to a significantly increased number of DNA strands double breaks with no influence on fertilisation rates.     

Effect of high altitude exposure on spermatogenesis and epididymal sperm count in male rats

The present study was designed to determine the effect of exposure to high altitude on spermatogenesis using transillumination technique and sperm count in male rats. In addition, the effect of oral intubation for intragastric administration of vehicle on testicular parameters in adult male rats in a schedule of 42 days was assessed. Male rats were exposed to Cerro de Pasco (Peru) at 4340 m for 3, 7, 14, 21, 28, 35 and 42 days resulting in a modification of the pattern of the seminiferous tubule stages. At day 3, stages I, IV-V, VI, VII and IX-XI were relatively shorter at high altitude than at sea level. At day 7, stages VIII, IX-XI, XII and XIII-XIV were reduced. At day 14, stages VII, VIII and IX-XI were reduced. At day 21 and 28, stages VIII, XII and XIII-XIV were significantly increased at high altitude. At day 35 an increase in stage XIII-XIV was observed. At day 42, stages II-III, IX-XI and XII were significantly increased at high altitude. Epididymal sperm count was significantly reduced at day 7 of exposure to high altitude and maintained low levels with respect to sea level up to 42 days. In conclusion, high altitude exposure affects spermatogenesis, particularly onset of mitosis and spermiation. This in turn affects epididymal sperm count.     

Protective effect of alpha glucosyl hesperidin (G‐hesperidin) on chronic vanadium induced testicular toxicity and sperm nuclear DNA damage in male Sprague Dawley rats

The study was conducted to evaluate the vanadium‐induced testicular toxicity and its effect on sperm parameters, sperm nuclear DNA damage and histological alterations in Sprague Dawley rats and to assess the protective effect of G‐hesperidin against this damage. Treatment of rats with vanadium at a dose of 1 mg kg bw^?1 for 90 days resulted in significant reduction in serum testosterone levels, sperm count and motility. Further, a parallel increase in abnormal sperm morphology and adverse histopathological changes in testis was also associated with vanadium administration when compared to normal control. Moreover, sperm chromatin dispersion assay revealed that vanadium induces sperm nuclear DNA fragmentation. A marked increase in testicular malondialdehyde levels and decreased activity of antioxidant enzymes such as superoxide dismutase and catalase indicates vanadium‐induced oxidative stress. Co‐administration of G‐hesperidin at a dose of 25 and 50 mg kg bw^?1 significantly attenuated the sperm parameters and histological changes by restoring the antioxidant levels in rat testis. These results suggested that vanadium exposure caused reduced bioavailability of androgens to the tissue and increased free radical formation, thereby causing structural and functional changes in spermatozoa. G‐hesperidin exhibited antioxidant effect by protecting the rat testis against vanadium‐induced oxidative damage, further ensures antioxidant potential of bioflavonoids.     

Methamphetamine induces abnormal sperm morphology, low sperm concentration and apoptosis in the testis of male rats

Methamphetamine has been reported to be an important drug in the field of reproductive toxicology. The aim of this study was to investigate the effects of methamphetamine administrations on sperm morphology, sperm concentration and apoptotic activity inside seminiferous tubule in male rats. Rats were administered a dose of 8 mg kg(-1) , intraperitoneally (IP), for acute group and a dose of 4 mg kg(-1) , IP, once daily for 14 days for sub-acute group. Percentage of normal sperm morphology was decreased in acute group when compared with control. Total numbers of sperm count were significantly decreased in acute and sub-acute groups. Apoptotic activities were most abundant in the seminiferous tubules of acute treated animals with a highly significant increase in the number of apoptotic cells per tubule. Those effects of methamphetamine seem to be dose-dependent. The results suggest that methamphetamine not only works as drug of abuse in central nervous system, but also in gametogenesis of males.     

Assessment of the effect of prolonged forced swimming on CD‐1 mice sperm morphology with and without antioxidant supplementation

As physical exercise has been shown to negatively affect sperm morphology, this study was undertaken to assess the effect of a 3‐min forced swimming protocol during 50 days, with and without administration of antioxidants [N‐acetylcysteine (NAC) and trans‐resveratrol], on sperm morphology in CD‐1 mice. Forty‐four 13‐week‐old CD‐1 mice were randomly allocated to four different groups: mice not submitted to exercise, control group (CG), mice submitted to swimming without administration of antioxidants (EX), mice submitted to swimming that received trans‐resveratrol supplementation [exercise group (EX)+Resv] and mice submitted to swimming exercise that received NAC supplementation (EX+NAC). The EX showed 30.5% of spermatozoa with normal morphology, showing significant differences with regard to the CG, which showed 58.5%. The groups receiving antioxidant supplements showed significantly higher percentages of spermatozoa with normal morphology in comparison with the EX group (EX+Resv: 64.1%, EX+NAC: 48.2%). The imposed model of forced swimming caused alterations in sperm morphology. The antioxidants employed seem to be suitable antioxidants for avoiding exercise‐associated sperm morphology anomalies in prolonged forced swimming exercise. Trans‐resveratrol has proven to be more efficient for this purpose.     

TUNEL assay: Establishing a sperm DNA fragmentation cut‐off value for Egyptian infertile men

Male factor infertility is responsible for half of all infertility cases. Conventional semen analysis is inadequate to evaluate male fertility. Sperm DNA fragmentation (SDF) test can be done by: direct methods such as Terminal deoxynucleotidyl transferase dUTP Nick‐End Labeling (TUNEL) and Comet assay, or indirect like Sperm Chromatin Structure Assay (SCSA) and Sperm Chromatin Dispersion (SCD). TUNEL assay measures both single‐ and double‐strand breaks and is technically less demanding, while SCSA tests for the susceptibility for nuclear DNA denaturation and samples should be sent to the reference lab. Studies showed that a single cut‐off value does not fit all. Therefore, this study aimed at establishing a cut‐off value to discriminate between fertile and infertile Egyptian men. We enrolled 354 infertile men and 40 proven fertile volunteers.TUNEL assay was performed using Apo‐Direct kit and bench top flow cytometer.The calculated SDF cut‐off value was 20.3% with a sensitivity of 96.6% and specificity of 87.5%, and the overall accuracy of the test was 95.7%. Sperm DNA fragmentation Test using TUNEL assay is valuable tool for male infertility evaluation, and it assists in offering the best treatment options based on it's results.     

Selection of normal spermatozoa with a vacuole‐free head (x6300) improves selection of spermatozoa with intact DNA in patients with high sperm DNA fragmentation rates

Intracytoplasmic morphologically selected sperm injection (IMSI, 6300× magnification with Nomarski contrast) of a normal spermatozoon with a vacuole‐free head could improve the embryo's ability to grow to the blastocyst stage and then implant. However, the most relevant indications for IMSI remain to be determined. To evaluate the potential value of IMSI for patients with a high degree of sperm DNA fragmentation (n = 8), different types of spermatozoa were analysed in terms of DNA fragmentation. Motile normal spermatozoa with a vacuole‐free head selected at 6300× magnification had a significantly lower mean DNA fragmentation rate (4.1 ± 1.1%, n = 191) than all other types of spermatozoa: non‐selected spermatozoa (n = 8000; 26.1 ± 1.5% versus 4.1 ± 1.1%; P < 0.005), motile spermatozoa (n = 444; 20.8 ± 2.7% versus 4.1 ± 1.1%; P < 0.001) and motile, normal spermatozoa selected at 200× magnification (n = 370; 18.7 ± 2.7% versus 4.1 ± 1.1%; P < 0.001) and then motile, morphometrically normal spermatozoa with anterior vacuoles (n = 368; 15.9 ± 2.9% versus 4.1 ± 1.1%; P < 0.05) or posterior vacuoles (n = 402; 22.5 ± 3.6% versus 4.1 ± 1.1%; P < 0.001) selected at 6300× magnification. For patients with high sperm DNA fragmentation rates, selection of normal spermatozoa with a vacuole‐free head (6300×) yields the greatest likelihood of obtaining spermatozoa with non‐fragmented DNA.     

The progesterone‐induced sperm acrosome reaction is a good option for the prediction of fertilization in vitro compared with other sperm parameters

Progesterone (P₄) is crucial for the physiological function of spermatozoa. In the study, we investigated the correlation between P₄‐induced sperm acrosome reaction (AR) and parameters including sperm progressive motility, normal morphology and sperm DNA fragmentation (SDF), and compared the in vitro fertilization (IVF) predictive values of these indicators based on the multivariate regressions analysis and receiver operator characteristics (ROC) curve analyses. The results demonstrated a negative correlation between P₄‐induced sperm AR and the SDF, with the correlation ?9.05 (?17.25 to ?0.84), p<0.05, n = 47). No relationship was found between the sperm progressive motility, normal morphology and the induced AR. The P₄‐induced AR and SDF were both significantly correlated to the fertilization rate. ROC curve analyses indicated that P₄‐induced AR was a better prognostic predictor for the fertilization rate compared with the SDF, with the areas under the curve 0.729 (0.580–0.849), p<0.01 and 0.637 (0.484–0.772), p=0.16 respectively. The cut‐off value for P₄‐induced AR to predict “50% fertilization rate” was 23.4% with sensitivity and specificity of 63.3% and 88.2% respectively. The overall results indicated that the assessment of P₄‐induced AR seemed to be a more sensitive indicator for fertilization rate in vitro compared with other sperm parameters.     

Evaluation of different doses of mashua (Tropaeolum tuberosum) on the reduction of sperm production, motility and morphology in adult male rats

Mashua is an edible-tuber crop that grows in the Andean region. Folk medicine describes the use of mashua to reduce reproductive function in men. The present study aimed: (i) to determine whether different doses of mashua (0.01, 0.1, 1 and 2 g kg(-1)) produced a dose-response reduction on sperm production and quality; and, (ii) to determine whether these anti-reproductive effects of mashua can be reversible after cessation of treatment (12 and 24 days of recovery time). Mashua-treated rats showed lower values of daily sperm production, epididymal and vas deferens sperm count and sperm motility; meanwhile, mashua increased the percentage of abnormal sperm morphology and epididymal sperm transit rate. The following variables follow a dose-response effect: sperm number in vas deferens, sperm motility and sperm transit rate. In addition, it was demonstrated that the reduction in reproduction function in male rats treated with mashua was reversible after 24 days of recovery time. Finally, lower doses mashua reduces sperm number and quality (motility and morphology), and these adverse effects on male reproductive system may be reversible after 24 days after cessation of the treatment.     

精子形态对体外受精-胚胎移植治疗结局及新生儿的影响

目的:探讨正常形态精子百分率对体外受精-胚胎移植(IVF-ET)治疗结局及新生儿的影响。方法:采用WHO严格标准法将精液标本分为3组:中度畸形组:正常形态精子百分率5%～10%,轻度畸形组:10%<正常形态精子百分率<15%,正常组:正常形态精子百分率≥15%,比较各组间正常受精率、卵裂率、优质胚胎率、种植率、临床妊娠率及新生儿情况。结果:各组间患者年龄(男、女方)差异不显著(P>0.05);中度畸形组正常受精率显著低于轻度畸形组(63.70%vs73.74%,P<0.05),但与正常组差异无统计学意义(63.70%vs68.05%,P>0.05);正常组的优质胚胎率最高,显著高于中度畸形组(44.83%vs35.75%,P<0.05),其他各指标3组间差异无统计学意义(P>0.05);280个移植周期共分娩125个婴儿,其中单胎分娩73例,双胎分娩26例,出生婴儿未见先天异常,3组间流产率、异位妊娠率、孕周、早产率、出生体重差异无统计学意义(P>0.05)。结论:正常形态精子百分率为5%～10%对常规体外受精的受精率无影响,但显著降低优质胚胎率,而10%<正常形态精子百分率<15%对常规体外受精治疗结局的各项指标均无明显影响;正常形态精子百分率在预测IVF-ET的助孕结局及新生儿情况方面存在一定局限性。     

Cryopiece,a novel carrier with faster cooling rate,high recovery rate and retrieval rate,for individual sperm cryopreservation

BackgroundCryopreservation of extremely few spermatozoa is still a major challenge for male fertility preservation. This study aims to evaluate the cooling rate, recovery rate, and retrieval rate, along with other parameters of spermatozoa that cryopreserved using Cryopiece, a novel carrier, for individual sperm cryopreservation.MethodsSemen samples from 60 fertile donors were collected, and each semen sample was screened for motile sperm and mixed with cryoprotective agent (CPA), and then frozen using Cryopiece, micro-straw, and mini-straws. The cooling rate, retrieval rate, and recovery rate, morphology, DNA fragmentation index (DFI) and mitochondrial membrane potential (MMP), were compared among the un-frozen sperm and the sperm cryopreserved using these carriers.ResultsCryopiece possessed the fastest cooling rate. After freeze-thaw, the average retrieval rate of sperm cryopreserved using Cryopiece was 96.25%, and the average recovery rate was 64.40%, which were higher than that of sperm cryopreserved using the other two carriers (71.42% and 54.30% for micro-straw, and 63.54% and 58.04% for mini-straw, respectively). There was no significant impact on DFI after sperm cryopreservation, and no significant difference in morphology between sperm cryopreserved using these carriers was observed. Though MMP of sperm changed significantly after cryopreservation, micro-straw maintained sperm MMP better than Cryopiece and mini-straw did, while no significant difference was observed in MMP between sperm cryopreserved using Cryopiece and mini-straw.ConclusionsCryopiece produced satisfying retrieval and recovery rates in sperm cryopreservation and should be an ideal carrier for cryopreservation of small number of sperm.     

微流控芯片精子分选法对精子常规参数及DNA完整性的影响

目的:研究微流控芯片精子优选技术对精子常规参数及DNA完整性的影响。方法:自行设计制作微流控芯片,利用芯片处理技术和上游法对40例精液标本进行精子优选,通过计算机辅助精液分析系统及染色质扩散试验从精子常规参数及DNA完整性两个方面评价精液体外处理对精子的影响。结果:精液经微流控芯片法和上游法处理后,精子活力、精子正常形态率以及精子尾部肿胀率均有显著提高(P<0.01),精子的DNA损伤率明显降低(P<0.01)。微流控芯片法与上游法相比,优选后前者精子DNA损伤率明显低于后者[(8.4±5.8)%vs(16.4±9.2)%,P<0.01],而其他参数差异无显著性。结论:微流控芯片技术在精子优选中能获得精子DNA损伤程度小的高质量精子。     

Quality of human spermatozoa: relationship between high‐magnification sperm morphology and DNA integrity

The aim of this work is to establish the relationship between the morphology of Intracytoplasmic Morphologically Selected Sperm Injection (IMSI)‐selected spermatozoa and their DNA integrity. The 45 ejaculates were randomly distributed into three treatment groups: normozoospermic, oligoasthenozoospermic and oligoasthenotheratozoospermic samples. The evaluation of DNA integrity was performed using the sperm chromatin dispersion test. It was established that DNA integrity of spermatozoa is strongly dependent on ejaculate quality (P < 0.05). The count of spermatozoa with nonfragmented DNA in normozoospermic samples was high and independent from IMSI‐morphological classes (Class 1 versus Class 3, respectively) (P > 0.1). With decreased ejaculate quality, the percentage of spermatozoa with nonfragmented DNA decreased significantly (P < 0.05) independent from morphological class. Nevertheless, the rate of IMSI‐selected spermatozoa with fragmented DNA within of Class 1 in normozoospermic (Group 1), in oligoasthenozoospermic (Group 2) and in oligoasthenotheratozoospermic (Group 3) samples was 21.1%, 31.8% and 54.1%, respectively. In conclusion, there is a direct relationship between morphological parameters of spermatozoa and their DNA integrity. However, the IMSI technique alone is not enough for the selection of spermatozoa with intact nuclei.