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1.
J Endocrinol ; 262(2)2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38829257

ABSTRACT

Cells actively engaged in de novo steroidogenesis rely on an expansive intracellular network to efficiently transport cholesterol. The final link in the transport chain is STARD1, which transfers cholesterol to the enzyme complex that initiates steroidogenesis. However, the regulation of ovarian STARD1 is not fully characterized, and even less is known about the upstream cytosolic cholesterol transporters STARD4 and STARD6. Here, we identified both STARD4 and STARD6 mRNAs in the human ovary but only detected STARD4 protein since the primary STARD6 transcript turned out to be a splice variant. Corpora lutea contained the highest levels of STARD4 and STARD1 mRNA and STARD1 protein, while STARD4 protein was uniformly distributed across ovarian tissues. Cyclic AMP analog (8Br-cAMP) and phorbol ester (PMA) individually increased STARD1 and STARD4 mRNA along with STARD1 protein and its phosphoform in cultured primary human luteinized granulosa cells (hGCs). STARD6 transcripts and STARD4 protein were unresponsive to these stimuli. Combining lower doses of PMA and 8Br-cAMP blunted the 8Br-cAMP stimulation of STARD1 protein. Increasing cholesterol levels by blocking its conversion to steroid with aminoglutethimide or by adding LDL reduced the STARD4 mRNA response to stimuli. Sterol depletion reduced the STARD1 mRNA and protein response to PMA. These data support a possible role for STARD4, but not STARD6, in supplying cholesterol for steroidogenesis in the ovary. We demonstrate for the first time how cAMP, PMA and sterol pathways separately and in combination differentially regulate STARD4, STARD6 and STARD1 mRNA levels, as well as STARD1 and STARD4 protein in human primary ovarian cells.


Subject(s)
Ovary , Humans , Female , Ovary/metabolism , Cholesterol/metabolism , Cells, Cultured , RNA, Messenger/metabolism , Adult , Phosphoproteins/metabolism , Phosphoproteins/genetics , 8-Bromo Cyclic Adenosine Monophosphate/pharmacology , Granulosa Cells/metabolism , Granulosa Cells/drug effects , Gene Expression Regulation/drug effects , Cyclic AMP/metabolism , Membrane Proteins/genetics , Membrane Proteins/metabolism , Membrane Transport Proteins
2.
Reprod Biomed Online ; 41(1): 69-79, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32505543

ABSTRACT

RESEARCH QUESTIONS: Can a previously defined relationship between sperm capacitation and the probability of a man generating pregnancy within three cycles, prospectively predict male fertility in diverse clinical settings? A second study asked, what is the prevalence of impaired sperm fertilizing ability in men questioning their fertility (MQF), and does this relate to traditional semen analysis metrics? DESIGN: In the multicentric, prospective observational study, data (n = 128; six clinics) were analysed to test a published relationship between the percentage of fertilization-competent, capacitated spermatozoa (Cap-Score) and probability of generating pregnancy (PGP) within three cycles of intrauterine insemination. Logistic regression of total pregnancy outcomes (n = 252) assessed fit. In the cohort comparison, Cap-Scores of MQF (n = 2155; 22 clinics) were compared with those of 76 fertile men. RESULTS: New outcomes (n = 128) were rank-ordered by Cap-Score and divided into quintiles (25-26 per group); chi-squared testing revealed no difference between predicted and observed pregnancies (P = 0.809). Total outcomes (n = 252; 128 new + 124 previous) were pooled and the model recalculated, yielding an improved fit (P < 0.001). Applying the Akaike information criterion found that the optimal model used Cap-Score alone. Cap-Scores were performed on 2155 men (with semen analysis data available for 1948). To compare fertilizing ability, men were binned by PGP (≤19%, 20-29%, 30-39%, 40-49%, 50-59%, ≥60%). Distributions of PGP and the corresponding Cap-Scores were significantly lower in MQF versus fertile men (P < 0.001). Notably, 64% of MQF with normal volume, concentration and motility (757/1183) had PGP of 39% or less (Cap-Scores ≤31), versus 25% of fertile men. CONCLUSIONS: Sperm capacitation prospectively predicted male fertility. Impaired capacitation affects many MQF with normal semen analysis results, informing diagnosis versus idiopathic infertility.


Subject(s)
Fertility/physiology , Fertilization/physiology , Infertility, Male/physiopathology , Sperm Capacitation/physiology , Spermatozoa/physiology , Female , Humans , Male , Pregnancy , Pregnancy Rate , Prospective Studies , Semen Analysis , Sperm Motility/physiology
3.
J Assist Reprod Genet ; 36(7): 1457-1469, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31187330

ABSTRACT

PURPOSE: To determine whether a selected set of mRNA biomarkers expressed in individual cumulus granulosa cell (CC) masses show association with oocyte developmental competence, embryo ploidy status, and embryo outcomes. METHODS: This prospective observational cohort pilot study assessed levels of mRNA biomarkers in 163 individual CC samples from 15 women stimulated in antagonist cycles. Nineteen mRNA biomarker levels were measured by real-time PCR and related to the development of their corresponding individually cultured oocytes and subsequent embryos, embryo ploidy status, and live birth outcomes. RESULTS: PAPPA mRNA levels were significantly higher in CC from oocytes that led to euploid embryos resulting in live births and aneuploid embryos compared to immature oocytes by ANOVA. LHCGR mRNA levels were significantly higher in CC of oocytes resulting in embryos associated with live birth compared to immature oocytes and oocytes resulting in arrested embryos by ANOVA. Using a general linearized mixed model to assess ploidy status, CC HSD3B mRNA levels in oocytes producing euploid embryos were significantly lower than other oocyte outcomes, collectively. When transferred euploid embryos outcomes were analyzed by ANOVA, AREG mRNA levels were significantly lower and PAPPA mRNA levels significantly higher in CC from oocytes that produced live births compared to transferred embryos that did not form a pregnancy. CONCLUSIONS: Collectively, PAPPA, LHCGR, and AREG mRNA levels in CC may be able to identify oocytes with the best odds of resulting in a live birth, and HSD3B1 mRNA levels may be able to identify oocytes capable of producing euploid embryos.


Subject(s)
Amphiregulin/genetics , Multienzyme Complexes/genetics , Oocytes/growth & development , Pregnancy-Associated Plasma Protein-A/genetics , Progesterone Reductase/genetics , Receptors, LH/genetics , Steroid Isomerases/genetics , Adult , Cumulus Cells/metabolism , Embryo Transfer , Embryonic Development/genetics , Female , Gene Expression Regulation, Developmental , Humans , In Vitro Oocyte Maturation Techniques , Oocyte Retrieval , Oocytes/metabolism , Oogenesis/genetics , Ovarian Follicle/growth & development , Ovarian Follicle/metabolism , Ploidies , Pregnancy , RNA, Messenger/genetics
4.
J Assist Reprod Genet ; 25(9-10): 437-43, 2008.
Article in English | MEDLINE | ID: mdl-18855132

ABSTRACT

PURPOSE: To describe the ultrastructure of spermatozoa from a patient with complete asthenozoospermia that resulted in live births following blastocyst culture. MATERIALS AND METHODS: Analyses of spermatozoa from a 36 year old patient were performed using light and electron microscopy. The hypo-osmotic swelling test was used to select spermatozoa for intracytoplasmic sperm injection. Embryos were cultured to the blastocyst stage. RESULTS: 100% of the spermatozoa had dynein arm deficiency with secondary defects varying from 3-17%. Six oocytes were injected; five fertilized normally and one was digynic. All five zygotes formed good quality blastocysts. Three blastocysts were cryopreserved and two blastocysts were transferred. Twin females were born at 37 weeks. CONCLUSIONS: The hypo-osmotic swelling test can be used to select viable immotile ejaculated spermatozoa from a patient with dynein arm deficiency and can produce excellent fertilization rates and blastocyst development resulting in live births.


Subject(s)
Blastocyst/cytology , Kartagener Syndrome/pathology , Sperm Injections, Intracytoplasmic , Spermatozoa/ultrastructure , Twins , Adult , Dyneins/metabolism , Embryo Culture Techniques , Embryo Transfer , Female , Flagella/ultrastructure , Humans , Male , Pregnancy , Semen Analysis , Sperm Motility
5.
Beijing Da Xue Xue Bao Yi Xue Ban ; 37(1): 94-5, 2005 Feb 18.
Article in English | MEDLINE | ID: mdl-15719052

ABSTRACT

Constitutional full trisomy 21 is a common disorder in which abnormal spermatogenesis has been previously described. However, constitutional mosaic trisomy 21 in an otherwise normal but infertile male has not been explored. We report a case with low level mosaic trisomy 21 in a non-syndrome but azoospermic patient. We also propose that the patient's azoospermia may be related to the constitutional mosaic trisomy 21 and thus resulting in a late onset of testicular failure.


Subject(s)
Azoospermia/complications , Azoospermia/genetics , Down Syndrome/complications , Down Syndrome/genetics , Adult , Humans , Male , Mosaicism
6.
Am J Obstet Gynecol ; 187(2): 285-7; discussion 287-8, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12193913

ABSTRACT

OBJECTIVE: The purpose of this study was to assess whether age, resting follicle number, intraovarian blood flow, and/or ovarian volume are predictive of follicular response and oocyte quality in patients with in vitro fertilization. STUDY DESIGN: A retrospective chart review was done on 90 in vitro fertilization cycles that were completed in a university setting. Multiple linear regression analysis was used to assess the predictive value of age, resting follicle number, pretreatment ovarian volume, and peak systolic velocity for response to gonadotropin stimulation. RESULTS: Age was predictive (P <.05) for the number of oocytes retrieved, the number that reached two pronuclei, and the number of embryos that reached > or = 4 cells by day 3 after insemination. Resting follicle number was also predictive of follicular response and subsequent embryonic development. Peak systolic velocity and ovarian volume were both found to be of no value. CONCLUSION: Age and resting follicle number can be used as additional parameters to support patient counseling before in vitro fertilization stimulation.


Subject(s)
Fertilization in Vitro/methods , Gonadotropins/therapeutic use , Oocytes/physiology , Ovarian Follicle/physiology , Ovulation Induction/methods , Adult , Age Factors , Blood Flow Velocity/physiology , Female , Humans , Multivariate Analysis , Oocytes/drug effects , Ovarian Follicle/blood supply , Ovarian Follicle/drug effects , Ovulation Induction/standards , Predictive Value of Tests , Regression Analysis , Retrospective Studies , Ultrasonography, Doppler
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