In vitro chemokine (C-C motif) receptor 6-dependent non-inflammatory chemotaxis during spermatogenesis.

BACKGROUND: Chemokine (C-C motif) receptor 6 (CCR6) is present in sperm and plays a significant role in sperm motility and chemotaxis acting in the reproductive tracts. However, the expression and functional significance of CCR6 in testis are still poorly understood, especially in the process of spermatogenesis. METHODS AND RESULTS: CCR6 was expressed in spermatogenic cell lines and its expression was shown in an age-dependent upregulation manner from puberty to adulthood in mouse testis. Immunostaining results confirmed the localization of CCR 6 in testis. Further chemotaxis assays demonstrated that spermatogenic cells GC-1 and -2 exhibited a directional movement toward CCR6-specific ligand such as CCL20 or Sertoli cells in vitro. CONCLUSIONS: The present findings indicate that CCR6 is involved in the chemotaxis of spermatogenic cells in vitro and promotes chemotaxis under non-inflammatory conditions during normal spermatogenesis.

[Testicular sperm cryopreservation for male fertility preservation].

OBJECTIVE: To investigate the effectiveness of testicular sperm cryopreservation in male fertility preservation by evaluating the clinical outcome of ICSI cycles with frozen-thawed testicular sperm for azoospermia patients. METHODS: We retrospectively analyzed 96 samples of cryopreserved testicular sperm obtained by testicular biopsy, vasovasostomy (V-V), vasoepididymostomy (V-E) , of which 55 were subjected to 60 ICSI cycles with frozen-thawed testicular sperm. We evaluated the rates of sperm recovery, fertilization, cleavage, transferable and good-quality embryos, clinical pregnancy, pregnancy outcome, and health of the newborns. RESULTS: All the frozen testicular sperm samples were recovered successfully. The rates of fertilization, 2PN fertilization, cleavage, available embryos and good-quality embryos were 77.6, 69.4, 99.4, 84.5 and 40.8%, respectively. There were transferable embryos in all cycles. Fresh embryos were transferred in 52 of the 60 cycles, with the clinical pregnancy rate of 57.7% (30/52), including 19 singletons and 11 twins, and the rates of implantation and miscarriage were 38.7% (41/106) and 3.33% (1/30). Up to the present time, there have been 20 healthy newborns, including 12 boys and 8 girls, and another 13 ongoing pregnancies. No birth defects have been found so far. CONCLUSION: Desirable clinical outcomes can be obtained from ICSI cycles with frozen-thawed testicular sperm, and testicular sperm cryopreservation is an effective method of fertility preservation for azoospermia males.

In vitro antioxidation effect of Quercetin on sperm function from the infertile patients with leukocytospermia.

PROBLEM: Quercetin has been shown to display intensive antioxidant activity against ROS-mediated damage in chilled semen, and the effects and molecular mechanisms of Quercetin on sperm function in the infertile patients with leukocytospermia remain largely unknown. METHODS: Semen samples were collected from the infertile men with leukocytospermia (n = 56) and fertile men (n = 44). Computer-assisted semen analysis (CASA) was used to determine sperm motility before and after Quercetin incubation (10 µmol/L). Changes in H2 O2 , sperm mitochondrial DNA (mtDNA), cytochrome B (Cty B), and NADH dehydrogenase 5 (NADH5) contents were measured. Furthermore, hyperactivated motility (HA) and acrosome reaction rates were detected after the stimulation by progesterone with or without Quercetin, respectively. RESULTS: Quercetin could significantly improve sperm motility from the leukocytospermic patients. The level of H2 O2 was significantly decreased in the supernatant of leukocytospermic patients after Quercetin treatment. The content of mtDNA in sperm was significantly decreased, whereas the contents of Cyt B and NADH 5 in sperm were significantly increased. Sperm hyperactivated motility and acrosome reaction induced by progesterone were enhanced by Quercetin in sperm from the infertile men with leukocytospermia. CONCLUSION: These data indicate Quercetin could display protective effects against oxidative damage on sperm from the infertile men with leukocytospermia.

CCL19/CCR7 contributes to the pathogenesis of endometriosis via PI3K/Akt pathway by regulating the proliferation and invasion of ESCs.

PROBLEM: The level of CCL19 increased in the peritoneal fluid of women with endometriosis, but the precise mechanism of CCL19/CCR7 in the pathogenesis of endometriosis remains unknown. METHODS: ELISA and immunohistochemistry were performed to analyze CCL19/CCR7 expressions in peritoneal fluid and endometrium from women with endometriosis (n = 38) and controls (n = 32). Cell proliferation and transwell invasion assays were applied to detect proliferation and invasion of human endometrial stromal cells (ESCs). Expressions of Bcl2, MMP2, MMP9, and p-AKT/AKT were analyzed by Western blot. RESULTS: Peritoneal fluid concentration of CCL19 in patients with endometriosis was higher than that in controls. Those patients with moderate/severe endometriosis had significantly higher peritoneal fluid concentrations of CCL19 compared to those with minimal/mild endometriosis. Higher CCL19 and CCR7 were found in the endometrium with endometriosis compared to control. CCL19 significantly enhanced ESC proliferation and invasion through CCR7 via activating PI3K/Akt signal pathways. CCL19/CCR7 interaction significantly enhanced phosphorylation of Akt, Bcl2, MMP2, and MMP9 in ESCs. CONCLUSION: These data indicate CCL19/CCR7 contributes to proliferation and invasion of ESCs, which are conducive to the pathogenesis of endometriosis through activating PI3K/Akt pathway.

CCR6 is required for ligand-induced CatSper activation in human sperm.

CatSper channel has been considered the principal sperm Ca2+ channel responsible for the cytosolic Ca2+ elevation required for various sperm functions necessary for fertilization [1-4]. However, the mechanism underlying the activation of CatSper channel by various physiological ligands remain incompletely understood. We have recently demonstrated the expression of C-C chemokine receptor 6 (CCR6) in sperm and Ca2+ influx upon binding of human ß-defensin 1 (DEFB1) to CCR6, which is important for sperm motility [5]. In the present study, we have demonstrated that CCR6 receptor and CatSper channel are both required for the Ca2+ entry/current induced by physiological ligands DEFB1, chemokine (C-C motif) ligand 20 (CCL20) and progesterone in human sperm. CCR6 is co-localized and interacts with CatSper in human sperm. Ca2+ influx mediated by CCR6 and CatSper is required for essential sperm functions, including motility, hyperactivation and acrosome reaction, which are impaired in infertile sperm showing reduced levels of CCR6 and CatSper. The present finding suggests a critical role of CCR6 receptor in mediating ligand-induced, CatSper-dependent Ca2+ influx required for various sperm functions and thus male fertility.

[Influence of cryoprotectant and cooling rate in vitrification method on the spindles of rabbit oocytes].

OBJECTIVE: To investigate the influence of cryoprotectants and cooling rates in vitrification method on the spindles of rabbit M II oocytes. METHODS: Rabbit oocytes were verified by using cryoloop with ethylene glycol (EG) singly or EG combined with dimethyl sulphoxide (DMSO) as cryoprotectants, and cooled by taking oocytes directly into liquid nitrogen or by vitrification machine. After frozen rabbit oocytes thawed, the microtubulin and chromosome of the spindles were fixation and stained by immunofluorescent method. Confocal microscope was used to reveal spindle configuration. RESULTS: In the two protocols of single EG used and EG combined with DMSO, the spindles were severely injured. But in protocol of EG combined with DMSO and at ultra-rapid cooling rate, the normal configuration of spindle rate of thawed rabbit oocytes was similar to that of the control group. CONCLUSION: The protocol of EG combined with DMSO as cryoprotectants and with extremely high cooling rate by vitrification machine can produce the best effect on conservation of spindle configuration in vitrification of rabbit oocytes.

In vitro chemokine (C-C motif) receptor 6-dependent non-inflammatory chemotaxis during spermatogenesis

BACKGROUND: Chemokine (C-C motif) receptor 6 (CCR6) is present in sperm and plays a significant role in sperm motility and chemotaxis acting in the reproductive tracts. However, the expression and functional significance of CCR6 in testis are still poorly understood, especially in the process of spermatogenesis. METHODS AND RESULTS: CCR6 was expressed in spermatogenic cell lines and its expression was shown in an age-dependent upregulation manner from puberty to adulthood in mouse testis. Immunostaining results confirmed the localization of CCR 6 in testis. Further chemotaxis assays demonstrated that spermatogenic cells GC-1 and -2 exhibited a directional movement toward CCR6-specific ligand such as CCL20 or Sertoli cells in vitro. CONCLUSIONS: The present findings indicate that CCR6 is involved in the chemotaxis of spermatogenic cells in vitro and promotes chemotaxis under non-inflammatory conditions during normal spermatogenesis.