Effect of Endometriosis on Cumulus ATP, Number of Mitochondria and Oocyte Maturity in Cumulus Oocyte Complex in Mice / Efeito da endometriose no cumulus ATP, número de mitocôndrias e maturidade oocitária no complexo oocitário cumulus em camundongos

Abstract Objective Endometriosis causes a decrease in oocyte quality. However, this mechanism is not fully understood. The present study aimed to analyze the effect of endometriosis on cumulus cell adenosine triphosphate ATP level, the number of mitochondria, and the oocyte maturity level. Methods A true experimental study with a post-test only control group design on experimental animals. Thirty-two mice were divided into control and endometriosis groups. Cumulus oocyte complex (COC) was obtained from all groups. Adenosine triphosphate level on cumulus cells was examined using the Elisa technique, the number of mitochondria was evaluated with a confocal laser scanning microscope and the oocyte maturity level was evaluated with an inverted microscope. Results The ATP level of cumulus cells and the number of mitochondria in the endometriosis group increased significantly (p < 0.05; p < 0.05) while the oocyte maturity level was significantly lower (p < 0.05). There was a significant relationship between ATP level of cumulus cells and the number of mitochondrial oocyte (p < 0.01). There was no significant relationship between cumulus cell ATP level and the number of mitochondrial oocytes with oocyte maturity level (p > 0.01; p > 0.01). The ROC curve showed that the number of mitochondrial oocytes (AUC = 0.672) tended to be more accurate than cumulus cell ATP level (AUC = 0.656) in determining the oocyte maturity level. Conclusion In endometriosis model mice, the ATP level of cumulus cells and the number of mitochondrial oocytes increased while the oocyte maturity level decreased. There was a correlation between the increase in ATP level of cumulus cells and an increase in the number of mitochondrial oocytes.

Efeitos do citrato de clomifeno, letrozol e estradiol sobre apoptose em células do cumulus oophorus humano / Effects of clomiphene citrate, letrozole and estradiol on apoptosis in human cumulus oophorus cells

Citrato de clomifeno (CC) e letrozol (LE) são indutores de ovulação que, apesar das altas taxas de ovulação confirmada, atingem baixas taxas de gravidez. Este estudo teve como objetivo investigar os efeitos de CC e LE in vitro, isoladamente ou em combinação com estradiol (E), na apoptose de células do cumulus oophorus humano. Realizamos um estudo prospectivo controlado utilizando culturas primárias de células do cumulus de pacientes submetidas à fertilização in vitro (n=22). A coloração com Giemsa e a imunocitoquímica para alfa-inibina foram utilizadas para avaliar a pureza e a morfologia da cultura celular. A viabilidade celular foi avaliada pelo ensaio MTT, o ciclo celular por citometria de fluxo e a expressão gênica de Caspase-3, Bax e Superóxido dismutase 2 (SOD-2) e S26 por reação em cadeia de polimerase (PCR) em tempo real. As células foram tratadas por 24 horas em 5 grupos de tratamento: CC, CC + E, LE, LE + E e controle. Nenhum dos tratamentos afetou a viabilidade celular, mas o LE reduziu a porcentagem média de células na fase S em relação ao controle (24,79 versus 21,70, p=0,0014). O tratamento com CC aumentou a expressão gênica de Bax (4 vezes) e SOD-2 (2 vezes), que foi revertida quando adicionado E à cultura. A expressão de SOD-2 aumentou em células tratadas com LE quando comparado ao controle (4 vezes), que foi também revertida por adição de E. Estes achados sugerem que CC e LE não afetam significativamente a viabilidade das células do cumulus humana. Porém, houve modulação na expressão de genes envolvidos na apoptose por essas drogas isoladamente e em associação com E, sugerindo que CC e LE podem ter efeitos diretos nas células do cumulus além de seus mecanismos de ação conhecidos.

Clomiphene citrate (CC) and letrozole (LE) are ovulatory stimulants that, despite high ovulation rates, achieve low pregnancy rates. This study aimed to investigate the in vitro effects of CC and LE, alone or in combination with estradiol (E), on apoptosis in human cumulus cells. We performed a controlled prospective study using primary cumulus cell cultures from patients undergoing in vitro fertilization (n=22). Giemsa stain and alpha-inhibin immunocytochemistry was used to assess cell culture purity and morphology. Cell viability was evaluated by MTT assay, cell cycle status by flow cytometry, and Caspase-3, Bax and superoxide dismutase 2 (SOD-2), and S26 gene expression by real-time polymerase chain reaction (qPCR). Cells were treated for 24 hours in 5 conditioned media: CC, CC + E, LE, LE + E and control. None of the treatments affected cell viability, but LE reduced the mean percentage of cells in the S phase compared to control (24.79 versus 21.70, p=0.0014). CC treatment increased mRNA expression of Bax (4 fold) and SOD-2 (2 fold), which was reversed by co-treatment with E. SOD-2 expression increased in cells treated with LE compared to control (4 fold), which was also reversed by E. These findings suggest that CC and LE do not significantly affect the viability of human cumulus cells. Still, the expression of genes involved in apoptosis was modulated by these drugs alone and in association with E, suggesting that CC and LE may have direct effects on cumulus cells beyond their known mechanisms of action.

Differential gene expression analysis of human cumulus cells / 대한생식의학회지

OBJECTIVE: This study was performed to explore the possibility that each oocyte and its surrounding cumulus cells might have different genetic expression patterns that could affect human reproduction. METHODS: Differential gene expression analysis was performed for 10 clusters of cumulus cells obtained from 10 cumulus-oocyte complexes from 10 patients. Same procedures related to oocyte maturation, microinjection, and microarray analyses were performed for each group of cumulus cells. Two differential gene expression analyses were performed: one for the outcome of clinical pregnancy and one for the outcome of live birth. RESULTS: Significant genes resulting from these analyses were selected and the top 20 affected pathways in each group were analyzed. Circadian entrainment is determined to be the most affected pathway for clinical pregnancy, and proteoglycans in cancer pathway is the most affected pathway for live birth. Circadian entrainment is also amongst the 12 pathways that are found to be in top 20 affected pathways for both outcomes, and has both lowest p-value and highest number of times found count. CONCLUSION: Although further confirmatory studies are necessary, findings of this study suggest that these pathways, especially circadian entrainment in cumulus cells, may be essential for embryo development and pregnancy.

Growth differentiation factor 9 and cumulus cell supplementation in in vitro maturation culture media enhances the viability of human blastocysts / 대한생식의학회지

OBJECTIVE: In vitro maturation (IVM) of immature oocytes can be useful for some infertile patients. In IVM programs, the rates of embryo formation and pregnancy are low. Therefore, it is essential to recognize the main factors involved in regulating oocyte maturation in vitro. The purpose of this study was to investigate the effects of growth differentiation factor 9 (GDF9) and cumulus cell (CC) supplementation in IVM medium on the rates of embryo formation and viability of human blastocysts.METHODS: A total of 80 germinal vesicle oocytes from stimulated cycles underwent an IVM program. The oocytes were divided into four groups, where group I consisted of IVM media only and served as the control, group II consisted of IVM+CCs, group III consisted of IVM+GDF9 (200 ng/mL), and group IV consisted of IVM+CCs+GDF9 (200 ng/mL). Intracytoplasmic sperm injection was performed on the IVM oocytes, and the cleavage embryos that were generated were vitrified. Following thawing, the embryos were cultured for 3 additional days, and the viability rates of the developed blastocysts were determined.RESULTS: The maturation rate of the oocytes did not differ significantly across the four groups. The fertilization rate in group II was significantly higher than that in the control group (76.5% vs. 46.2%). Embryo formation was significantly more frequent in all experimental groups than in the control group, while blastocyst formation did not show significant differences in the three experimental groups compared to the control. The mean viability rates in groups II, III, and IV were 58.16%, 55.91%, and 55.95%, respectively, versus 37.78% in the control group (p<0.05).CONCLUSION: Supplementation of IVM culture media with GDF9 and CCs enhanced the fertilization, embryo formation, and viability rates of blastocysts generated from vitrified cleavage embryos.

Electrophysiological responses to different follicle-stimulating hormone isoforms on human cumulus oophorus cells: preliminary results / Respostas eletrofisiológicas a diferentes isoformas de FSH em células humanas do cumulus oophorus: resultados preliminares

Abstract Objective The aim of the present study was to provide a better understanding of the specific action of two follicle-stimulating hormone (FSH) isoforms (β-follitropin and sheep FSH) on the membrane potential of human cumulus cells. Methods Electrophysiological data were associated with the characteristics of the patient, such as age and cause of infertility. The membrane potential of cumulus cells was recorded with borosilicate microelectrodes filled with KCl (3 M) with tip resistance of 15 to 25 MΩ. Sheep FSH and β-follitropin were topically administered onto the cells after stabilization of the resting potential for at least 5 minutes. Results In cumulus cells, the mean resting membrane potential was - 34.02 ± 2.04 mV (n = 14). The mean membrane resistance was 16.5 ± 1.8 MΩ (n = 14). Sheep FSH (4 mUI/mL) and β-follitropin (4 mUI/mL) produced depolarization in the membrane potential 180 and 120 seconds after the administration of the hormone, respectively. Conclusion Both FSH isoforms induced similar depolarization patterns, but β-follitropin presented a faster response. A better understanding of the differences of the effects of FSH isoforms on cell membrane potential shall contribute to improve the use of gonadotrophins in fertility treatments.

Resumo Objetivo O objetivo do presente estudo foi fornecer uma melhor compreensão da ação específica de duas isoformas de hormônio folículo estimulante (FSH, sigla em inglês) (β-folitropina e FSH ovino) no potencial de membrana de células do cumulus oophorus humanas. Métodos Dados eletrofisiológicos foram associados às características da paciente, como idade e causa da infertilidade. O potencial de membrana das células do cumulus foi registrado com microeletrodos de borossilicato preenchidos com KCl (3 M) com uma resistência de 15 a 25 MΩ. O FSH ovino e a β-folitropina foram administrados topicamente nas células após a estabilização do potencial de repouso durante pelo menos 5 minutos. Resultados Nas células do cumulus, o potencial médio de membrana em repouso foi de -34,02 ± 2,04 mV (n = 14). A resistência média da membrana foi de 16,5 ± 1,8 MΩ (n = 14). O FSH ovino (4 mUI/mL) e a β-folitropina (4 mUI/mL) produziram despolarização no potencial de membrana 180 e 120 segundos após a aplicação do hormônio, respectivamente. Conclusão Ambas as isoformas de FSH induzem padrões de despolarização semelhantes, mas a β-folitropina apresentou uma resposta mais rápida. Uma melhor compreensão das diferenças dos efeitos das isoformas do FSH no potencial da membrana celular contribuirá para aprimorar o uso das gonadotrofinas no estímulo ovariano controlado e em protocolos de maturação oocitária in vitro.

Comparison of the culture methods between human cumulus cells and mural granulosa cells / 中国病理生理杂志

AIM:To establish an effective method for purification and culture of human cumulus cells(CCs) in vitro,and to compare the characteristics between CCs and mural granulosa cells(MGCs).METHODS:Follicular fluid and cumulus complex from the patients undergoing intracytoplasmic sperm injection were collected.CCs were mechanically cut from cumulus complex and then directly inoculated on a Petri dish, and MGCs were obtained from follicular fluid through density gradient centrifugation.The expression of follicle stimulating hormone receptor(FSHR)was determined by immunofluorescence.The cell growth curves were measured by CCK-8 assay.The secretion of estrogen was detected by ELISA.RESULTS:After incubated for 24 h, the adherence of CCs was observed.CCs and MGCs had similar growth characteristics and FSHR expression.The similar cell growth curves were observed by CCK-8 assay and the results of ELISA showed that they had comparable secretion of estrogen.CONCLUSION:Direct culture of CCs mechanically cutting from cumulus complex is an effective method.CCs had similar growth characteristics,growth curves and secretion of estro-gen to MGCs cultured in vitro and could be a substitutive source of granulosa cell subsets.

Expressão do mRNA para IGF-2 em oócitos e células do cumulus extraídos de folículos antrais e pré-antrais de ovelhas nativas do Estado de Pernambuco / IGF-2 mRNA expression in oocytes and cumulus cells of antral and preantral native sheep follicles in Pernambuco State, Brazil

Objetivou-se avaliar a expressão do mRNA para o gene do fator de crescimento IGF-2 em oócitos e células do cumulus de ovelhas em diferentes estágios do desenvolvimento folicular. Os folículos classificados morfologicamente como antrais (terciários e pré-ovulatórios) foram aspirados manualmente para obtenção dos oócitos e células do cumulus. Os folículos pré-antrais (secundários) foram extraídos do córtex ovariano, por microdissecção, e os oócitos retirados. Nos dois grupos, os oócitos foram desnudados e agrupados em "pools" de dez células cada (Grupo A, n=10; Grupo B, n=10) e dez amostras com grupos de células do cumulus (Grupo A1, n=10, B1, n=10). O mRNA foi extraído e convertido em cDNA utilizando a técnica da RT-PCR, utilizando Oligo DT randômico para o mRNA. A análise da expressão confirmou a expressão gênica para IGF-2 nos grupos de oócitos e células do cumulus. Houve um aumento da expressão relativa do mRNA para IGF-2 nos grupos de oócitos durante a fase mais tardia do desenvolvimento folicular e as diferenças foram consideradas significantes (p<0,05). Não houve variação significante da expressão de IGF2 entre os grupos de células do cumulus. Conclui-se que o fator de crescimento IGF-2 tem níveis mais elevados de expressão em oócitos ovinos, na segunda fase do desenvolvimento folicular, mas expressão semelhante em células do cumulus durante as fases estudadas do desenvolvimento folicular.(AU)

The aim of this study was to analyze the mRNA expression of IGF-2 growth factor in oocytes and cumulus cells from native sheep follicles at different stages of follicular development. The classified morphologically as antral follicles (tertiary preovulatory) were aspirated manually to obtain the oocyte and the cumulus cells. The preantral follicles (secondary) were extracted from the ovarian cortex by microdissection, and oocytes were removed. In both groups, oocytes were denuded and grouped into "pools" of ten cells each (Group A, n=10, Group B, n=10) and ten samples with groups of cumulus cells (Group A1, n=10; B1, n=10). The mRNA was extracted and converted to cDNA using the RT-PCR technique. The expression analysis confirmed the expression of IGF-2 gene for groups of oocyte and the cumulus cells. There was an increase in the relative expression of mRNA for IGF-2 for groups of oocytes during the later stage of follicular development and differences were considered significant (p<0.05). There was no significant variation in the expression of IGF2 between groups of cumulus cells. It is concluded that the growth factor IGF-2 has higher levels of expression in sheep oocytes in the second stage of follicular development in the conditions adopted and similar expression in cumulus cells during various stages of follicular development.(AU)

Effect of serum containing Jinghou Zengzhi Recipe on expression of GDF9 and Bim in ovarian COCs and CCs in controlled ovarian hyperstimulation rats / 重庆医学

Objective To observe the effects of serum containing Jinghou Zengzhi Recipe (JHZZ) on the expression of growth differentiation factor 9 (GDF9) and Bim in cumulus-oocyte complexes (COCs) and cumulus cells (CCs) of controlled ovarian hyperstimulation (COH) rats,and to investigate its curative effect and mechanism.Methods The rat COH ovarian model was prepared for collecting COCs and CCs,which were respectively co-cultured in vitro with the blank serum of female COH SD rat and serum containing JHZZ,and the each group was divided into 3 subgroups:the blank serum group (blank group),serum containing JHZZ group (control group) and serum containing JHZZ plus GDF9 receptor blocker group (experimental group),total 6 subgroups.COCs and CCs were collected after 24 h.The expression levels of GDF9 and Bim mRNA were detected by real-time quantitative PCR.The GDF9 protein expression levels were detected by Western blot.Results (1) The expression level of GDF9 mRNA in control group COCs was obviously higher than that in the control group and experiment group COCs (P＜0.05);the Bim mRNA expression level in COCs of control group and experiment group was significantly lower than that in COCs of blank group (P＜ 0.05);the GDF9 protein expression level in the control group COCs was significantly higher than that in the blank group COCs (P＜0.05),and also higher than that in the experiment group COCs,but the difference was not statistically significant (P＞0.05).(2)The comparison results of GDF9 mRNA expression level in CCs among 3 groups were consistent with those in COCs;the Bim mRNA expression level in CCs of control group and experimental group was significantly lower than that in the blank group (P＜ 0.05);the Bim mRNA expression level in the control group CCs was significantly lower than that in the experimental group CCs (P＜0.05);the GDF9 protein expression level in the control group CCs was significantly higher than that in the blank group and experimental group CCs (P＜0.05).(3)The GDF9 mRNA expression level in the control group COCs was significantly higher than that in CCs (P＜0.05),and the other inter-group comparisons between COSs and CCs had no statistical difference (P＞0.05).Conclusion Serum containing JHZZ can increase the GDF9 expression level in COCs and CCs,maintain the low expression of Bim in COCs and CCs,inhibit the ovarian cells apoptosis and promote the follicular development;COCs is more conducive to the expression of GDF9 mRNA compared with CCs eliminating oocyte.

Mulheres inférteis com endometriose pélvica mínima e leve submetidas à estimulacão ovariana apresentam menor expressão do gene CYP19A1 em células do cumulus / Infertile women with minimal and mild endometriosis submitted tocontrolled ovarian stimulation present lower expression of the gene CYP19A1 in cumulus cells

Objetivo: Menores taxas de gestação em portadoras de endometriose submetidas a técnicas de reprodução assistida podem estar relacionadas à piora da qualidade oocitária. A análise da expressão gênica em células do cumulus (CC) pode fornecer biomarcadores passíveis de predizer a qualidade gamética. O objetivo deste estudo foi comparar os níveis da expressão do gene CYP19A1 em CC de mulheres inférteis com endometriose mínima/leve (I/II) e controles inférteis. Método: Foram selecionadas pacientes com infertilidade por endometriose pélvica inicial e por fator masculino e/ou tubário (grupo controle), submetidas à estimulação ovariana controlada para injeção intracitoplasmática de espermatozoide (ICSI). Imediatamente após a captação oocitária, CC foram isoladas e armazenadas. Foi realizada a quantificação da expressão do gene CYP19A1 nas CC por meio de PCR-Real Time. Resultados: Foram isoladas CC de 23 mulheres inférteis com endometriose I/II e de 41 controles. Observou-se expressão significativamente menor do gene CYP19A1 em CC de mulheres inférteis com endometriose I/II (0,56 ± 0,17) quando comparadas às controles (0,15 ± 0,04) (p = 0,043). Conclusões: A menor expressão do gene CYP19A1 em CC de mulheres inférteis com endometriose pélvica em estágios iniciais pode mediar a piora da qualidade oocitária, abrindo novas perspectivas no entendimento da etiopatogênese da infertilidade relacionada à doença.

Objective: Lower pregnancy rate in women with endometriosis submitted to assisted reproductive techniques might be related to poor oocyte quality. The analysis of the expression of the genes in cumulus cells (CC) might provide biomarkers that can predict gamete quality. The main objective of the present study was to compare the levels of the expression of the gene CYP19A1 in CC of infertile women with minimal and mild (I/II) endometriosis and infertile controls. Method: There were selected patients with infertility caused by initial pelvic endometriosis and by male/tubal factor (control group), submitted to controlled ovarian stimulation to ICSI. Immediately after the oocyte retrieval, CC were isolated and stored. Quantification of the expression of the gene CYP19A1 in CC was performed using PCR-real time.Results: CC were isolated from 23 infertile women with endometriosis I/II and 41 from control. Significant lower expression of the gene CYP19A1 in CC was observed in infertile women with endometriosis I/II (0.56 ± 0.17) when compared to control (0.15 ± 0.04) (p = 0,043). Conclusions: The lower expression of the gene CYP19A1 in CC of infertile women with pelvic endometriosis in initial stages might mediate the poor oocyte quality, opening new perspectives on the understanding of the etiopathogenesis of infertility related to the disease.

Efeito das células do cumulus e cisteamina durante o cultivo de maturação in vitro de oócitos bovinos sobre a maturação nuclear e aquisição da competência para desenvolvimento embrionário / Effects of cumulus cells and cysteamine during bovine oocyte in vitro maturation on meiosis progression and acquisition of developmental competence

Complexos cumulus-oócito (COC), oócitos desnudos (DO) e DO cocultivados com células do cumulus em suspensão (DO+CC) foram maturados in vitro (MIV) na presença ou ausência de cisteamina (50mM). Observou-se efeito benéfico da cisteamina durante o cultivo de MIV, pois a maturação nuclear no grupo COC cisteamina foi maior do que a do COC controle (P<0,05). No grupo sem a adição de cisteamina, foi observado que a ausência de CC durante o cultivo de MIV prejudicou a maturação nuclear em DO, em relação ao COC (P<0,05), todavia a cisteamina restaurou a capacidade de progressão da meiose em DO, tornando-os semelhantes aos COC (P>0,05). O acoplamento entre oócitos e CC durante MIV demonstrou ser essencial para aquisição da competência do oócito para suportar o desenvolvimento embrionário inicial, pois COC apresentaram maior porcentagem de blastocistos e eclosão quando comparados a DO e DO+CC (P<0,05). A inclusão de cisteamina no cultivo de MIV não restaurou a aquisição da competência em DO e DO+CC, que permaneceram semelhantes aos do grupo-controle (P>0,05). Conclui-se que a cisteamina no meio de MIV melhora as taxas de maturação nuclear em COC e restaura a capacidade de progressão da meiose em DO. Todavia, na concentração utilizada neste estudo, não promove efeito benéfico no desenvolvimento embrionário.

Cumulus-oocyte complexes (COC), denuded oocytes (DO) and DO co-cultured with cumulus cells in suspension (DO+CC) were in vitro matured (IVM) in the presence or absence of cysteamine (50mM). A beneficial effect of cysteamine was observed during IVM, because the nuclear maturation in the COC cysteamine group was higher than in COC control (P<0.05). In the control group, the absence of CC during IVM impaired nuclear maturation in DO when compared to COC (P<0.05), but cysteamine restored the ability of meiosis progression in DO, making them similar to COC (P>0.05). The coupling between oocytes and CC during IVM proved to be essential for the acquisition of oocyte competence to support early embryonic development, as COC had higher percentages of blastocyst and hatching when compared to DO and DO+DC (P<0.05). However, the inclusion of cysteamine in the IVM culture did not restore the acquisition of competence in DO and DO+DC, which remained similar to the control group (P>0.05). It is concluded that cysteamine in the IVM culture improves the nuclear maturation in COC and restores the progression ability of meiosis in DO. However, in the concentration used in this study, cysteamine does not promote a beneficial effect on embryo development.

Influência da interação entre o oócito e as células da granulosa nos resultados dos procedimentos de reprodução assistida / The influence of interaction between oocyte and granulosa cells on the results of procedures in assisted reproduction

A interação oócito-células da granulosa in vivo e sua influência na qualidade oocitária e embrionária tem sido alvo de inúmeros estudos, mas muitas questões ainda necessitam ser esclarecidas. O objetivo deste trabalho foi revisar a importância dessa comunicação, estabelecendo uma relação com a questão da maturação in vitro de oócitos imaturos humanos aplicando esses conhecimentos para definir possíveis marcadores moleculares que poderiam melhorar a seleção de oócitos e, consequentemente, selecionar embriões de boa qualidade para posterior transferência e sucesso de gravidez de pacientes submetidas ao tratamento da infertilidade conjugal. As células da granulosa têm um importante papel na maturação oocitária in vitro e os benefícios da presença dessas células durante essa etapa podem ser atribuídos à formação de um microambiente favorável (bioquímico e metabólico) ao redor do oócito. Foram identificados nesta revisão vários marcadores em potencial nas células do cumulus de oócitos competentes, incluindo vários genes que poderiam ser usados como preditores da competência oocitária, o que pode contribuir para a formulação de critérios mais objetivos e confiáveis para a seleção de oócitos e embriões, e consequente aprimoramento e otimização das técnicas em reprodução humana assistida que são aplicadas nos procedimentos clínicos atuais de fertilização in vitro.

The interaction of oocyte-granulosa cells in vivo and in vitro and its influence on oocyte and embryo quality has been the subject of numerous studies, but many issues still need to be clarified. The objective of this study was to promote a review about the importance of this communication establishing a connection with the issue of in vitro maturation of immature human oocytes by applying this knowledge to define potential molecular markers that could improve the selection of oocytes and consequently select good quality embryos for later transfer and success of pregnancy in patients undergoing treatment of infertility. The granulosa cells also have an important role in oocyte maturation in vitro and the venefits from the presence of these cells during this process can be atributed to the formation of a favorable micro-environment (biochemical and metabolic) around the oocyte. In this review, we identified several potential markers in the cumulus cells of competent oocytes, including several genes that could be used as predictors of oocyte competence, which contributes for more objective and reliable criteria for the selection of oocytes and embryos, thus improving and optimizing techniques in assisted human reproduction that are applied in current clinical in vitro fertilization.

A Simple Technique for Immature Oocytes Rescue by In-vitro-maturation Culture in Controlled Ovarian Hyperstimulation Cycles / 中山大学学报(医学科学版)

[Objective]To evaluate the role of mature cumulus cells from oocyte-cumulus complex(OCC)in in-vitro maturation(IVM)and establish a new culture technique which is convenient to carry out.[Methods]The cumulus cells of OCC were cut off and dispersed by 1 mL syringe.The cumulus cells were co-cultured with the immature oocytes retrieved from the COH cycles after they adherent to the bottom of the dish.The immature oocytes were experienced IVM procedures in different culture media.They were divided into 3 groups(the oocytes at germinal vesicle stage from one woman were allotted to the same group randomly).Group 1(solution A):basic culture medium+human follicular fluid(hFF);Group 2(solution B):solution A+ cumulus cells(OCC);Group 3(solution C):solution A+ OCC+ follicle stimulating hormone(FSH)+ epidermal growth factor (EGF).Then,the maturation rate,fertilization rate and formation rate of available embryo were observed.[Results]In 113 treatment cycles,298 immature oocytes were performed IVM with solution A,B,and C.The difference for 24 hour maturation rates among 3 groups wag statistically significant(A:45.2%,B:61.7%,C:78.2%,P＜0.05).There was no statistical difference for 25～48 hour maturation rates and normal fertilization rates of mature oocytes.The differences of cleavage rates and rescued embryo rates between group 1 and 2,group 1 and 3 were statistically significant(P＜0.05).The formation rates of available embryo showed an increasing trend from group 1,2,to 3.[Conclusion]After being dispersed by simply beat upon with syringe and adherent culture,the mature cumulus eells from mature OCCs in COH cycles,together with growth factors in the follicular fluid or extraneously supplemented,could promote the IVM of immature oocyte.

Autologous somatic cell nuclear transfer in pigs using recipient oocytes and donor cells from the same animal

The objective of the present study was to examine the feasibility of the production of autologous porcine somatic cell nuclear transfer (SCNT) blastocysts using oocytes and donor cells from slaughtered ovaries. Therefore, we attempted to optimize autologous SCNT by examining the effects of electrical fusion conditions and donor cell type on cell fusion and the development of SCNT embryos. Four types of donor cells were used: 1) denuded cumulus cells (DCCs) collected from in vitro-matured (IVM) oocytes; 2) cumulus cells collected from oocytes after 22 h of IVM and cultured for 18 h (CCCs); 3) follicular cells obtained from follicular contents and cultured for 40 h (CFCs); and 4) adult skin fibroblasts. The DCCs showed a significantly (p > 0.01) lower rate of fusion than the CCCs when two pulses of 170 V/mm DC were applied for 50 microsec (19 +/- 2% vs. 77 +/- 3%). The rate of DCC fusion with oocytes was increased by the application of two DC pulses of 190 V/mm for 30 microsec, although this was still lower than the rate of fusion in the CCCs (33 +/- 1% vs. 80 +/- 2%). The rates of cleavage (57 +/- 5%) and blastocyst formation (1 +/- 1%) in the DCC-derived embryos did not differ from those (55 +/- 6% and 3 +/- 1%, respectively) in the CCC-derived SCNT embryos. Autologous SCNT embryos derived from CFCs (5 +/- 2%) showed higher levels of blastocyst formation (p > 0.01) than CCC-derived autologous SCNT embryos (1 +/- 0%). In conclusion, the results of the present study show that culturing cumulus and follicular cells before SCNT enhances cell fusion with oocytes and that CFCs are superior to CCCs in the production of higher numbers of autologous SCNT blastocysts.