OBJECTIVETo explore the effects of fertilization methods and sperm sources in intracytoplasmic sperm injection (ICSI) on the developmental capacity of surplus embryos.

METHODSWe analyzed the blastocyst formation of the surplus embryos from 2 135 patients, who were divided according to fertilization methods into an IVF (n=1803) and an ICSI group (n=332), the former again allocated to a normal fertilization (n=1642) and a rescue fertilization group (n=161), and the latter, according to sperm sources, to an ejaculated (n=248), an epididymal (n=70) and a testicular sperm group (n=14). The rates of blastocyst formation and good-quality blastocysts were compared between different fertilization methods and sperm sources.

RESULTSA total of 1884 blastocysts (28.87%) formed from 6525 surplus embryos of the patients after sequential culture, of which 974 (51.70%) were good-quality ones. The blastocyst formation rate of surplus embryos was significantly higher in the IVF (30.14%) than in the ICSI group (21.40%, P < 0.05), the rate of good-quality blastocysts was also higher in the former (52.44%) than in the latter (45.54%), but with no significant difference (P > 0.05). The rates of blastocyst formation and good-quality blastocysts were significantly higher in the normal (31.04% and 53.28%) than in the rescue fertilization IVF group (20.38% and 38.54%, P < 0.05), and in the testicular sperm ICSI group (30.23% and 53.85%) than in either the epididymal (18.36% and 42.11%) or the ejaculated sperm ICSI group (21.76% and 45.70%) (P < 0.05).

CONCLUSIONThe development potential of surplus embryos was higher in IVF than in ICSI, in the normal than in the rescue fertilization IVF group, and in the testicular than in the epididymal and ejaculated sperm ICSI groups.

Blastocyst ; Embryonic Development ; Female ; Fertilization in Vitro ; methods ; Humans ; Male ; Oocytes ; Sperm Capacitation ; Sperm Injections, Intracytoplasmic ; methods ; Sperm Motility

The sperm plasma membrane is rich in polyunsaturated fatty acids and a variety of proteins, and its function is associated with sperm capacitation, acrosome reaction and sperm-egg fusion. Sperm fertilizability can be predicted by detecting the function of the sperm plasma membrane, which is performed mainly with the following five techniques: sperm hypoosmotic swelling test, Eosin gamma water test, sperm membrane lipid peroxidation determination, seminal plasma superoxide dismutase determination, and flow cytometry. The evaluation of the function of sperm plasma membrane can be applied in detecting semen quality, selecting semen centrifugation, assessing the quality and fertilizability of sex-sorted sperm, improving cryopreservation, and guiding the optimization of intracytoplasmic sperm injection. This review presents an update on the principles, methods and steps of the detection of sperm plasma membrane function, as well as an overview of its status quo and application.
Cell Membrane ; physiology ; Flow Cytometry ; Humans ; Male ; Semen Analysis ; Semen Preservation ; Sperm Capacitation ; Sperm Injections, Intracytoplasmic ; Sperm Motility ; Spermatozoa ; physiology

Sexual reproduction is marked by the fusion of the sperm cell with the oocyte during fertilization to produce the diploid zygote, in which the lipids in the sperm plasma membrane play an important role. Due to the loss of most cell organelles and DNA transcription, spermatozoa lack protein expression and vesicular transport. However, the lipids of the sperm plasma membrane undergo complicated dynamic changes, which may facilitate the capacitation, binding with zona pellucida, acrosome reaction and fusion of the sperm cell with the oocyte. This paper summarizes the progress in the studies of the lipids in the sperm plasma membrane, their composition, structure, peroxidation, metabolism and role in fertilization.
Acrosome Reaction ; Animals ; Cell Membrane ; chemistry ; Fertilization ; Humans ; Male ; Membrane Lipids ; metabolism ; Sperm Capacitation ; Spermatozoa ; chemistry

OBJECTIVETo investigate the progesterone-binding site on the normal fertile human sperm membrane after 2 hours of in vitro capacitation.

METHODSViable spermatozoa were selected by a swim-up method. After 2 hours of in vitro capacitation, multipoint saturation binding experiments were performed. Sperm suspension and increasing concentrations of progesterone-11alpha-glucuronide-[125I] iodotyramine (125I-P) were added to 7 total binding tubes respectively, and equal amounts of sperm suspension and 125I-P were added to another 7 corresponding non-specific binding tubes in the presence of 10 micromol/L progesterone. After incubation for 1 hour at 4 degrees C, the radioactivity of both the tubes and the pellets after centrifugation was measured respectively. The equilibrium dissociation constant (Kd) and maximum binding capacity (Bmax) were calculated using the mathematical model of single site multi-point saturation method of Scatchard function and least-squares regression.

RESULTSKd was (0.61 +/- 0.04) nmol/L and Bmax was (830 +/- 344) sites/cell. The significance test of the regression equation indicated that r = -0.980, P < 0.01.

CONCLUSIONThere is a high affinity and low capacity binding site for the progesterone (progesterone receptor) on the normal fertile human sperm membrane.

Adult ; Cell Membrane ; chemistry ; Humans ; Male ; Progesterone ; Radioligand Assay ; Receptors, Progesterone ; analysis ; Sperm Capacitation ; Spermatozoa ; chemistry

Ion channels in mammal sperm, including Ca2+, Na+, K+, Cl- and HCO3- channels, each play a key role in the process of sperm capacitation. Ca2+, HCO3- and ROS, as signal molecules, activate soluble adenylyl cyclase (sAC) with the cooperation of cyclic adenosine monophosphate (cAMP), Ca2+ and intracellular pH and, via a cross talk between the cAMP/protein kinase A (PKA) and tyrosine phosphatase signaling pathways, promote the biological effect of sperm capacitation.
Animals ; Humans ; Ion Channels ; metabolism ; Ions ; metabolism ; Male ; Mammals ; Signal Transduction ; Sperm Capacitation ; physiology

The luminal fluid environment of the female reproductive tract is considered critical for the sperm to undergo a series of molecular events leading to the final acquisition of their fertilizing capacity. It has been shown that the fluid in the female reproductive tract contains high content of HCO3- and it plays an important role in sperm functions including sperm motility, capacitation, hyperactivation and acrosome reaction. This review summarizes the effects of HCO3- on sperm functions occurring in the female reproductive tract and discusses the transport mechanisms involved in mediating uterine HCO3- secretion. New evidence is also presented to show possible cause of female infertility due to defective HCO3- transporting mechanism.
Animals ; Bicarbonates ; metabolism ; Female ; Fertilization ; physiology ; Humans ; Male ; Sperm Capacitation ; physiology ; Sperm-Ovum Interactions ; physiology ; Uterus ; metabolism ; secretion

OBJECTIVETo evaluate the role of sperm kinematic parameters in the hyperactivation of Guinea pig spermatozoa, and to confirm the index of their hyperactivated motility.

METHODSComputer-aided sperm analysis (CASA) was used to describe the kinesis parameters of the Guinea pig spermatozoa incubated for 1, 3, 5 and 7 hours.

RESULTSThe curvilinear velocity, average path velocity and amplitude of lateral head displacement were increased with time and reached the peak at 5 hours, while the straight linear velocity, linearity, straightness and beat cross frequency were gradually decreased with time and hit the bottom at 5 hours.

CONCLUSIONThe sperm movement pattern changes greatly before hyperactivation during the capacitation of Guinea pig spermatozoa.

Animals ; Guinea Pigs ; Kinetics ; Male ; Numerical Analysis, Computer-Assisted ; Sperm Capacitation ; physiology ; Sperm Motility ; physiology ; Spermatozoa ; physiology

Sperm must be capacitated before sperm-ovum fusion. Capacitation was once considered as hyperactivation. But now many investigators thought that capacitation wasn't equal to hyperactivation, and that sperm hyperactivation might be a moiety of capacitation or the result of capacitation. In the present, the methods used to study sperm capacitation include fertilization in vitro, induction of sperm acrosome reaction, FITC-labeled chlortetracycline and plant hemoagglutinin. The studies on sperm capacitation in vitro mainly focused on the inductive substances of sperm capacitation and subsequent results analysis. It could lay foundation for the manifestation of molecular mechanism of sperm capacitation and destination of sperm capacitation in molecular levels.
Adenylyl Cyclases ; physiology ; Bicarbonates ; metabolism ; Calcium ; metabolism ; Humans ; Male ; Phosphorylation ; Sperm Capacitation ; drug effects ; physiology ; Sperm Motility

The physiological changes that occur to sperm during the residence in the female tract are collectively referred to as "capacitation". The mechanism of action by which these compounds promote capacitation is poorly understood at the molecular level. However, some molecular events significant to the initiation of capacitation have been identified, such as the correlation of capacitation with cholesterol efflux from the sperm plasma membrane, increased membrane fluidity, modulations in intracellular ion concentrations, hyperpolarization of the sperm plasma membrane and increased protein tyrosine phosphorylation. This review discusses recent progress in elucidation mechanisms which regulate sperm capacitation.
Bicarbonates ; metabolism ; Calcium ; metabolism ; Cholesterol ; metabolism ; Cyclic AMP ; physiology ; Humans ; Ion Transport ; Male ; Membrane Potentials ; Phosphorylation ; Sperm Capacitation

Protein palmitoylation, one of post-translation modifications, refers to the addition of saturated 16-carbon palmitic acid to cysteine residues via the thioester bond. It plays key roles in various functional activities, such as the interaction, stability and location of proteins. Heat shock protein 90 (Hsp90), an important molecular chaperone, has been reported to be involved in sperm capacitation. However, it remains unclear whether protein palmitoylation exists in sperm and whether Hsp90 in sperm is palmitoylated under different physiological conditions. In this study, we examined whether the protein palmitoylation is present in mouse cauda epididymis sperm using acyl-biotin exchange method, predicted the potential palmitoylated sites of Hsp90 by the software CSS-Palm 4.0 and detected the palmitoylated Hsp90 in the mouse sperm from caput epididymis and cauda epididymis by immunoprecipitation. We found that some proteins, approximately 50, 65, 72, 85 and 130 kDa, were palmitoylated in mouse cauda epididymis sperm. Five sites in two Hsp90 isoforms were predicted to be palmitoylated. The results also showed that Hsp90 in mouse sperm was palmitoylated and its palmitoylation level was involved in different physiological conditions: the palmitoylation level of cauda epididymis sperm was higher than that of caput epididymis sperm; and the palmitoylation level after capacitation was much higher than that before capacitation. In conclusion, this study reveals that protein palmitoylation is present in mouse sperm and the palmitoylated Hsp90 is associated with different physiological conditions in sperm.
Animals ; Epididymis ; HSP90 Heat-Shock Proteins ; metabolism ; Lipoylation ; Male ; Mice ; Palmitic Acid ; chemistry ; Sperm Capacitation ; Spermatozoa ; metabolism