Phospholipase C zeta(PLC)is a key sperm-borne oocyte-activating factor that triggers Ca^(2+)oscillations and the subsequent block to polyspermy following gamete fusion.Mutations in PLCZ1,the gene encoding PLCζ,cause ...Phospholipase C zeta(PLC)is a key sperm-borne oocyte-activating factor that triggers Ca^(2+)oscillations and the subsequent block to polyspermy following gamete fusion.Mutations in PLCZ1,the gene encoding PLCζ,cause male infertility and intracytoplasmic sperm injection(ICSI)fertilization failure;and PLCζ expression and localization patterns are significantly correlated with ICSI fertilization rate(FR).However,in conventional in vitro fertilization(cIVF),whether and how sperm PLCζ affects fertilization remain unclear.Herein,we identified one previously reported and two novel PLCZ1 mutations associated with polyspermy in vitro that are characterized by excessive sperm-zona binding and a delay in pronuclei(PN)formation.Immunofluorescence staining and oocyte activation testing revealed that virtually all spermatozoa from patients lacked functional PLCζ and were thus unable to evoke Ca^(2+) oscillations.ICSI with an artificial oocyte activation treatment successfully rescued the polyspermic phenotype and resulted in a live birth.Furthermore,we analyzed PLCζ in an additional 58 males after cIVF treatment in the Reproductive and Genetic Hospital of CiTiC-Xiangya(Changsha,China)between February 2019 and January 2022.We found that the proportion of spermatozoa that expressed PLCζ was positively correlated with both 2PN rate and total FR.The optimal cutoff value below which males were likely to experience low FR(total FR≤30%)after clVF was 56.7%for the proportion of spermatozoa expressing PLC5.Our study expands the mutation and the phenotypic spectrum of PLCZ1 and further suggests that PLCζ constitutes a promising biomarker for identifying low FRs cases in cIVF due to sperm-related oocyte activation deficiency and that sperm PLCζ analysis may benefit the widermale population and not onlymen with IcsI failure.展开更多
Objective:To investigate the influence of age,body mass index(BMI),varicocele,diabetes,tobacco use,and environmental occupational risks on sperm DNA fragmentation index(DFI)and its association with semen parameters an...Objective:To investigate the influence of age,body mass index(BMI),varicocele,diabetes,tobacco use,and environmental occupational risks on sperm DNA fragmentation index(DFI)and its association with semen parameters and in vitro fertility(IVF)outcomes.Methods:This cross-sectional study was conducted on 116 infertile men.Conventional semen parameters were analyzed according to the World Health Organization criteria.Sperm DNA fragmentation was evaluated using sperm chromatin dispersion method.After visiting the infertility center,the men's height and weight were measured,and blood tests were performed to check for diabetes,and medical records were reviewed for varicocele,tobacco use,and type of occupation.The sperm was then examined for DFI.Then,the association between sperm DFI and IVF failure rate was investigated.Results:The study showed a significant association between DFI≥20%with BMI(OR 1.134,95%CI 1.04-1.24,P=0.006),varicocele(OR 4.330,95%CI 1.25-14.96,P=0.021),tobacco use(OR 3.066,95%CI 1.06-8.90,P=0.039)and environmental and occupational risks(OR 2.694,95%CI 1.08-6.75,P=0.034)as well as sperm motility(P<0.05).Although the amount of DNA damage increased in those aged≥40 years,there was no significant association between the amount of DFI≥≥20%and age,diabetes,sperm volume and concentration,morphology and progressive rate(P>0.05).The IVF failure rate was higher in people with a DFI≥20%.Conclusions:Factors such as BMI,varicocele,improper working conditions and environment cause damage to sperm DNA,and DFI≥20%damage can have adverse effects on IVF outcomes.展开更多
Terrestrial ecosystems heavily depend on vegetation,which responds to carbon dioxide(CO_(2))fertilization in hot and humid regions.The subtropical humid karst region is a hot and humid region;whether and to what exten...Terrestrial ecosystems heavily depend on vegetation,which responds to carbon dioxide(CO_(2))fertilization in hot and humid regions.The subtropical humid karst region is a hot and humid region;whether and to what extent CO_(2)fertilization affects vegetation changes in such regions remains unclear.In this study,we investigated the degree to which CO_(2)fertilization influences vegetation changes,along with their spatial and temporal differences,in the subtropical humid karst region using time-lag effect analysis,a random forest model,and multiple regression analysis.Results showed that CO_(2)fertilization plays an important role in vegetation changes,exhibiting clear spatial variations across different geomorphological zones,with its degree of influence ranging mainly between 11%and 25%.The highest contribution of CO_(2)fertilization was observed in the karst basin and non-karstic region,whereas the lowest contribution was found in the karst plateau region.Previous studies have primarily attributed vegetation changes in subtropical humid karst region to ecological engineering,leading to an overestimation of its contribution to these changes.The findings of this study enhance the understanding of the mechanism of vegetation changes in humid karst region and provide theoretical and practical insights for ecological and environmental protection in these regions.展开更多
基金supported by grants from the National Natural Science Foundation of China(No.81901553 to CD)the Natural Science Foundation of Hunan Province,China(No.2021JJ30461 to CD).
文摘Phospholipase C zeta(PLC)is a key sperm-borne oocyte-activating factor that triggers Ca^(2+)oscillations and the subsequent block to polyspermy following gamete fusion.Mutations in PLCZ1,the gene encoding PLCζ,cause male infertility and intracytoplasmic sperm injection(ICSI)fertilization failure;and PLCζ expression and localization patterns are significantly correlated with ICSI fertilization rate(FR).However,in conventional in vitro fertilization(cIVF),whether and how sperm PLCζ affects fertilization remain unclear.Herein,we identified one previously reported and two novel PLCZ1 mutations associated with polyspermy in vitro that are characterized by excessive sperm-zona binding and a delay in pronuclei(PN)formation.Immunofluorescence staining and oocyte activation testing revealed that virtually all spermatozoa from patients lacked functional PLCζ and were thus unable to evoke Ca^(2+) oscillations.ICSI with an artificial oocyte activation treatment successfully rescued the polyspermic phenotype and resulted in a live birth.Furthermore,we analyzed PLCζ in an additional 58 males after cIVF treatment in the Reproductive and Genetic Hospital of CiTiC-Xiangya(Changsha,China)between February 2019 and January 2022.We found that the proportion of spermatozoa that expressed PLCζ was positively correlated with both 2PN rate and total FR.The optimal cutoff value below which males were likely to experience low FR(total FR≤30%)after clVF was 56.7%for the proportion of spermatozoa expressing PLC5.Our study expands the mutation and the phenotypic spectrum of PLCZ1 and further suggests that PLCζ constitutes a promising biomarker for identifying low FRs cases in cIVF due to sperm-related oocyte activation deficiency and that sperm PLCζ analysis may benefit the widermale population and not onlymen with IcsI failure.
文摘Objective:To investigate the influence of age,body mass index(BMI),varicocele,diabetes,tobacco use,and environmental occupational risks on sperm DNA fragmentation index(DFI)and its association with semen parameters and in vitro fertility(IVF)outcomes.Methods:This cross-sectional study was conducted on 116 infertile men.Conventional semen parameters were analyzed according to the World Health Organization criteria.Sperm DNA fragmentation was evaluated using sperm chromatin dispersion method.After visiting the infertility center,the men's height and weight were measured,and blood tests were performed to check for diabetes,and medical records were reviewed for varicocele,tobacco use,and type of occupation.The sperm was then examined for DFI.Then,the association between sperm DFI and IVF failure rate was investigated.Results:The study showed a significant association between DFI≥20%with BMI(OR 1.134,95%CI 1.04-1.24,P=0.006),varicocele(OR 4.330,95%CI 1.25-14.96,P=0.021),tobacco use(OR 3.066,95%CI 1.06-8.90,P=0.039)and environmental and occupational risks(OR 2.694,95%CI 1.08-6.75,P=0.034)as well as sperm motility(P<0.05).Although the amount of DNA damage increased in those aged≥40 years,there was no significant association between the amount of DFI≥≥20%and age,diabetes,sperm volume and concentration,morphology and progressive rate(P>0.05).The IVF failure rate was higher in people with a DFI≥20%.Conclusions:Factors such as BMI,varicocele,improper working conditions and environment cause damage to sperm DNA,and DFI≥20%damage can have adverse effects on IVF outcomes.
基金National Natural Science Foundation of China,No.41761003The Karst Science Research Center of Guizhou Province,No.U1812401。
文摘Terrestrial ecosystems heavily depend on vegetation,which responds to carbon dioxide(CO_(2))fertilization in hot and humid regions.The subtropical humid karst region is a hot and humid region;whether and to what extent CO_(2)fertilization affects vegetation changes in such regions remains unclear.In this study,we investigated the degree to which CO_(2)fertilization influences vegetation changes,along with their spatial and temporal differences,in the subtropical humid karst region using time-lag effect analysis,a random forest model,and multiple regression analysis.Results showed that CO_(2)fertilization plays an important role in vegetation changes,exhibiting clear spatial variations across different geomorphological zones,with its degree of influence ranging mainly between 11%and 25%.The highest contribution of CO_(2)fertilization was observed in the karst basin and non-karstic region,whereas the lowest contribution was found in the karst plateau region.Previous studies have primarily attributed vegetation changes in subtropical humid karst region to ecological engineering,leading to an overestimation of its contribution to these changes.The findings of this study enhance the understanding of the mechanism of vegetation changes in humid karst region and provide theoretical and practical insights for ecological and environmental protection in these regions.
