Effects of BMP-4 and FSH on growth, morphology and mRNA expression of oocyte-secreted factors in cultured bovine secondary follicles

This study evaluated the effect of different concentrations of bone morphogenetic protein-4 (BMP-4), as well as the interaction of BMP-4 and follicle stimulating hormone (FSH) on growth, ultrastructural integrity, and expression of mRNA for growth differentiation factor-9 (GDF-9), BMP-15, maternal antigen that the embryo requires (Mater) and nucleoplasmin-2 (Npm-2) in bovine secondary follicles cultured in vitro for 18 days. Follicles cultured in the presence of 50 ng/ml BMP-4 had a progressive increase in their diameters with the increase of culture period from 0 to 6 and 12 days, but no significant differences were observed among treatments. The presence of both FSH and BMP-4 in a culture medium did not stimulate follicle growth when compared to the control medium. After 12 days, the percentage of normal follicles was maintained similar to that of day 0 in the medium supplemented with both FSH and BMP-4, but no significant differences among treatments were observed after 18 days of culture. BMP-4 maintained the ultrastructural integrity of follicles after 18 days of culture, while follicles cultured in medium supplemented with FSH or both BMP-4 and FSH had oocyte with irregular zona pellucida, vesicular bodies, and an abundance of vacuoles. Follicles cultured in the presence of BMP-4 had an increase in the levels of BMP-15 mRNA, when compared to those cultured in medium supplemented with FSH alone. In conclusion, the addition of BMP-4 in culture medium contributes to preserve follicular ultrastructure, but BMP-4 did not interact positively with FSH. Regarding secondary follicles cultured in the presence of FSH, BMP-4 increases the expression of mRNA for BMP-15.(AU)

Effects of BMP-4 and FSH on growth, morphology and mRNA expression of oocyte-secreted factors in cultured bovine secondary follicles

This study evaluated the effect of different concentrations of bone morphogenetic protein-4 (BMP-4), as well as the interaction of BMP-4 and follicle stimulating hormone (FSH) on growth, ultrastructural integrity, and expression of mRNA for growth differentiation factor-9 (GDF-9), BMP-15, maternal antigen that the embryo requires (Mater) and nucleoplasmin-2 (Npm-2) in bovine secondary follicles cultured in vitro for 18 days. Follicles cultured in the presence of 50 ng/ml BMP-4 had a progressive increase in their diameters with the increase of culture period from 0 to 6 and 12 days, but no significant differences were observed among treatments. The presence of both FSH and BMP-4 in a culture medium did not stimulate follicle growth when compared to the control medium. After 12 days, the percentage of normal follicles was maintained similar to that of day 0 in the medium supplemented with both FSH and BMP-4, but no significant differences among treatments were observed after 18 days of culture. BMP-4 maintained the ultrastructural integrity of follicles after 18 days of culture, while follicles cultured in medium supplemented with FSH or both BMP-4 and FSH had oocyte with irregular zona pellucida, vesicular bodies, and an abundance of vacuoles. Follicles cultured in the presence of BMP-4 had an increase in the levels of BMP-15 mRNA, when compared to those cultured in medium supplemented with FSH alone. In conclusion, the addition of BMP-4 in culture medium contributes to preserve follicular ultrastructure, but BMP-4 did not interact positively with FSH. Regarding secondary follicles cultured in the presence of FSH, BMP-4 increases the expression of mRNA for BMP-15.

Steady-state levels of vasoactive intestinal peptide (VIP) mRNA in goat ovaries and the effect of VIP on the in vitro development of isolated preantral follicles

The aims of this study were to verify the steady-state level of vasoactive intestinal peptide (VIP) mRNA in goat follicles at various developmental stages and to investigate the influence of VIP on the survival, antrum formation and growth of secondary follicles cultured for 6 days. Primordial, primary and secondary goat follicles and small and large antral follicles were obtained to quantify VIP mRNA by real-time reverse transcription with the polymerase chain reaction. The influence of VIP and the presence or absence of follicle-stimulating hormone (FSH) on the development of secondary follicles and on mRNA expression for VIP and FSH receptor (FSHR) were determined after 6 days of culture. Survival, antrum formation and follicular diameter were evaluated every other day of culture. The levels of VIP mRNA in primary and secondary follicles were significantly higher than in primordial follicles. Cumulus–oocyte complexes (COCs) from both small and large antral follicles had significantly higher levels ofVIP mRNA than their respective granulosa/theca cells. During culture, the addition of VIP and/or FSH had o effect on follicular development. However, the presence of FSH and/or VIP in the culture medium significantly reduced VIP mRNA levels, but did not alter FSHR mRNA levels. In conclusion, VIP mRNA was detected in all goat follicular categories and cellular types, VIP and/or FSH did not affect the development of secondary follicles and reduce the expression of VIP mRNA levels.(AU)

Steady-state levels of vasoactive intestinal peptide (VIP) mRNA in goat ovaries and the effect of VIP on the in vitro development of isolated preantral follicles

The aims of this study were to verify the steady-state level of vasoactive intestinal peptide (VIP) mRNA in goat follicles at various developmental stages and to investigate the influence of VIP on the survival, antrum formation and growth of secondary follicles cultured for 6 days. Primordial, primary and secondary goat follicles and small and large antral follicles were obtained to quantify VIP mRNA by real-time reverse transcription with the polymerase chain reaction. The influence of VIP and the presence or absence of follicle-stimulating hormone (FSH) on the development of secondary follicles and on mRNA expression for VIP and FSH receptor (FSHR) were determined after 6 days of culture. Survival, antrum formation and follicular diameter were evaluated every other day of culture. The levels of VIP mRNA in primary and secondary follicles were significantly higher than in primordial follicles. Cumulus–oocyte complexes (COCs) from both small and large antral follicles had significantly higher levels ofVIP mRNA than their respective granulosa/theca cells. During culture, the addition of VIP and/or FSH had o effect on follicular development. However, the presence of FSH and/or VIP in the culture medium significantly reduced VIP mRNA levels, but did not alter FSHR mRNA levels. In conclusion, VIP mRNA was detected in all goat follicular categories and cellular types, VIP and/or FSH did not affect the development of secondary follicles and reduce the expression of VIP mRNA levels.

Proteínas morfogenéticas ósseas (BMPs) e seu papel na regulação da oogênese e da foliculogênese ovariana em mamíferos / The bone morphogenetic proteins (BMPs) and its role in the regulation of ovarian folliculogenesis and oogenesis in mammalian

O processo de foliculogênese é controlado por uma variedade de gonadotrofinas e de fatores de crescimento locais, que agem em conjunto para regular a formação e o desenvolvimento dos folículos ovarianos. Dentre esses fatores, destacam-se as proteínas morfogenéticas ósseas (BMPs), que representam uma família de fatores de crescimento amplamente estudados e que se caracterizam por controlar as funções ovarianas em diferentes estágios do desenvolvimento folicular. Dessa forma, a presente revisão tem como foco principal descrever os locais de expressão das BMPs dos tipos 2, 4, 6, 7 e 15 e discutir o papel delas, bem como das gonadotrofinas FSH e LH durante a foliculogênese em mamíferos.(AU)

The process of folliculogenesis is controlled by a variety of gonadotropins and local growth factors that act together to regulate formation and development of ovarian follicles. Among these factors, the bone morphogenetic proteins (BMPs) represent a family of growth factors widely studied that have important functions at different stages of ovarian follicular development. Thus, this review aims to describe the local of expression and to discuss the role of BMPs 2, 4, 6, 7 and 15 as well as the gonadotropins FSH and LH during folliculogenesis in mammals. (AU)

Proteínas morfogenéticas ósseas (BMPs) e seu papel na regulação da oogênese e da foliculogênese ovariana em mamíferos / The bone morphogenetic proteins (BMPs) and its role in the regulation of ovarian folliculogenesis and oogenesis in mammalian

O processo de foliculogênese é controlado por uma variedade de gonadotrofinas e de fatores de crescimento locais, que agem em conjunto para regular a formação e o desenvolvimento dos folículos ovarianos. Dentre esses fatores, destacam-se as proteínas morfogenéticas ósseas (BMPs), que representam uma família de fatores de crescimento amplamente estudados e que se caracterizam por controlar as funções ovarianas em diferentes estágios do desenvolvimento folicular. Dessa forma, a presente revisão tem como foco principal descrever os locais de expressão das BMPs dos tipos 2, 4, 6, 7 e 15 e discutir o papel delas, bem como das gonadotrofinas FSH e LH durante a foliculogênese em mamíferos.

The process of folliculogenesis is controlled by a variety of gonadotropins and local growth factors that act together to regulate formation and development of ovarian follicles. Among these factors, the bone morphogenetic proteins (BMPs) represent a family of growth factors widely studied that have important functions at different stages of ovarian follicular development. Thus, this review aims to describe the local of expression and to discuss the role of BMPs 2, 4, 6, 7 and 15 as well as the gonadotropins FSH and LH during folliculogenesis in mammals.

FSH and LH enhance the development of goat preantral follicles cultured in vitro

This study evaluated th e effect of increased follicle stimulating hormone (FSH) concentrations on the expression of mRNA for LH receptors after in vitro culture of goat preantral follicles ( ≥ 150 μm) for 18 days. It also investigated whether the addition of luteinizing hormone (LH) to the culture medium, which contained increasing concentrations of FSH throughout the culture period, influenced the surv ival, growth and antrum formation of in vitro cultured goat preantral follicles. In experiment 1, preantral follicles were cultured in α -MEM + or α -MEM + supplemented with increasing concentrations of FSH throughout the culture period (sequential medium: FSH 100 ng/ml (days 0 to 6), FSH 500 ng/ml (days 6 to 12) and FSH 1000 ng/ml (days 12 to 18). The expression of luteinizing hormone receptor (LHR) was analyzed in noncultured and cultured follicles using real time RT-PCR. In experiment 2, isolated preantral follicles were cultured for 18 days in a sequential medium containing FSH (control) or a control medium supplemented with LH (50 or 100 ng/ml) from day 12 of culture onwards. Follicle development was evaluated on the basis of antr al cavity formation as well as follicular and oocyte growth after in vitro maturation. FSH stimulated a significant increase in the expression of mRNA for LH receptors after 18 days of culture. Furthermore, after 18 days, all tested media promoted follicular survival and antrum formation; however, a significant increase in the rate of follicular growth and resumption of meiosis was ob served when LH was used compared to the control. In conclusion, preantral follicles cultured in a medium supplemented with FSH increased LH receptor mR NA levels. Moreover, the addition of LH to the culture medium containing increasing concentrations of FSH (sequential medium) improved the in vitro development of goat preantral follicles.

FSH and LH enhance the development of goat preantral follicles cultured in vitro

This study evaluated th e effect of increased follicle stimulating hormone (FSH) concentrations on the expression of mRNA for LH receptors after in vitro culture of goat preantral follicles ( ≥ 150 μm) for 18 days. It also investigated whether the addition of luteinizing hormone (LH) to the culture medium, which contained increasing concentrations of FSH throughout the culture period, influenced the surv ival, growth and antrum formation of in vitro cultured goat preantral follicles. In experiment 1, preantral follicles were cultured in α -MEM + or α -MEM + supplemented with increasing concentrations of FSH throughout the culture period (sequential medium: FSH 100 ng/ml (days 0 to 6), FSH 500 ng/ml (days 6 to 12) and FSH 1000 ng/ml (days 12 to 18). The expression of luteinizing hormone receptor (LHR) was analyzed in noncultured and cultured follicles using real time RT-PCR. In experiment 2, isolated preantral follicles were cultured for 18 days in a sequential medium containing FSH (control) or a control medium supplemented with LH (50 or 100 ng/ml) from day 12 of culture onwards. Follicle development was evaluated on the basis of antr al cavity formation as well as follicular and oocyte growth after in vitro maturation. FSH stimulated a significant increase in the expression of mRNA for LH receptors after 18 days of culture. Furthermore, after 18 days, all tested media promoted follicular survival and antrum formation; however, a significant increase in the rate of follicular growth and resumption of meiosis was ob served when LH was used compared to the control. In conclusion, preantral follicles cultured in a medium supplemented with FSH increased LH receptor mR NA levels. Moreover, the addition of LH to the culture medium containing increasing concentrations of FSH (sequential medium) improved the in vitro development of goat preantral follicles.(AU)

Effects of BMP-7 and FSH on the development of goat preantral follicles and levels of mRNA for FSH-R, BMP-7 and BMP receptors after in-vitro culture

This study aimed to evaluate the effects of FSH and BMP - 7 on growth and on expression of FSH - R , BMP - 7 and BMP receptors in cultured secondary follicles. Goat secondary follicles (~200 μm) were isolated and cultured in vitro, with 5% CO 2 in air at 39°C, for 6 days in the presence of BMP - 7 (50 ng/m l ) supplemented or not with FSH (50 ng/m l ). Follicular diameter and the formation of the antrum were evaluated before and after culture. For each treatment, at the end of culture period, groups of 6 follicles were collected and, after extraction of total RNA and cDNA synthesis, the levels of mRNA for FSH - R, BMP - 7 and BMP receptors in cultured secondary follicles were quantified by real time PCR. The results showed that addition of BMP - 7 or F SH to culture medium stimulated growth of secondary follicles , while addition of both BMP - 7 and FSH was needed to significantly increase the percentage of follicles forming an antrum and the follicular levels of mRNA for both BMP - 7 and FSH - R. For BMP receptors, FSH reduced the levels of mRNA for BMPR - IA and BMP - RII in comparison with those follicles cultured in MEM alone and supplemented with BMP - 7, respectively. In conclusion , l ike FSH, BMP - 7 affect s in vitro growth of cultured secondary follicle s , but it stimulates antrum formation and expression of the mRNA ’s for BMP - 7 and FSH - R only in presence of both BMP - 7 and FSH . However, the levels of mRNA f or BMP - RIA and BMP - RII are reduced in follicles culture d in medium supplemented with FSH.

Uso de fluxofenim em trigo como protetor ao herbicida s-metolachlor / Fluxofenim applied on wheat as a safener for protection against smetolachlor herbicide

Este trabalho teve o objetivo de avaliar a eficiência do protetor fluxofenim no tratamento de sementes de trigo, cultivar Ônix, para o aumento da seletividade do herbicida S-metolachlor aplicado em pré-emergência e determinar a atividade da enzima de detoxificação glutationa S-transferase (GST). O trabalho foi realizado em duas etapas: a primeira para a avaliação em campo da eficiência do protetor em reduzir sintomas visuais de fitointoxicação causados pelo herbicida, e a segunda para a determinação da atividade da GST, conduzida em laboratório. Os tratamentos utilizados foram: aplicação ou não do protetor na dose de 40 mL por 100 kg de sementes e a pulverização do herbicida S-metolachlor nas doses de 1.440 e 2.880 mL i.a.ha-1, além de uma testemunha sem aplicação, sendo que, na determinação da atividade da GST, se excluiu o tratamento com aplicação de 2.880 mL i.a.ha-1 de S-metolachlor. Foram comparadas a suscetibilidade ao herbicida por meio da avaliação visual de injúrias aos 3, 7, 15 e 30 dias após a emergência (DAE) e a massa seca de raiz e parte aérea aos 10 DAE. Para a determinação da atividade da GST foram coletadas amostras da parte aérea das plantas aos 15 dias após a aplicação dos tratamentos e aos 10 DAE. Apesar do fluxofenim utilizado no tratamento da cultivar de trigo conferir uma maior tolerância ao herbicida S-metolachlor, ocorreu fitointoxicação visual e redução do estande de plantas. A cultivar testada apresentou aumento na atividade da enzima GST quando da utilização do fluxofenim anteriormente à aplicação do herbicida S-metolachlor na dose de 1.440 mL i.a. ha-1.

This work aimed to evaluate the effectiveness of fluxofenim used for seed treatment as safener in wheat, Ônix cultivar, treated with the herbicide S-metolachlor applied in pre-emergence. The study was divided in two steps. The first step consisted of an evaluation of fluxofenim's safener potential for the reduction of visual symptoms of S-metolachlor injury in the field, and the treatments were S-metolachlor at 1,440 and 2,880 mL i.a. ha-1 and fluxofenim at 0, and 40 mL per 100 kg of seeds, and a control without herbicide. The second step was to evaluate glutathione S-transferase activity (GST). Herbicide phytotoxity was measured by way of visual symptoms at 3, 7, 15, and 30 days after emergence (DAE), dry matter from roots and leaves at 10 DAE. For the determination of GST activity, the canopy of plants was collected at 10 DAE and 15 days after treatment application. The wheat presented low tolerance to S-metolachlor at both rates, and fluxofenim increased S-metolachlor selectivity to wheat but not sufficiently, reducing plant population to a nonacceptable level. Gluthationa S-transferase activity for wheat increased when seeds treated with fluxofenim were submitted to S-metolachlor at 1,440 mL a.i. ha-1.

Effects of BMP-7 and FSH on the development of goat preantral follicles and levels of mRNA for FSH-R, BMP-7 and BMP receptors after in-vitro culture

This study aimed to evaluate the effects of FSH and BMP - 7 on growth and on expression of FSH - R , BMP - 7 and BMP receptors in cultured secondary follicles. Goat secondary follicles (~200 μm) were isolated and cultured in vitro, with 5% CO 2 in air at 39°C, for 6 days in the presence of BMP - 7 (50 ng/m l ) supplemented or not with FSH (50 ng/m l ). Follicular diameter and the formation of the antrum were evaluated before and after culture. For each treatment, at the end of culture period, groups of 6 follicles were collected and, after extraction of total RNA and cDNA synthesis, the levels of mRNA for FSH - R, BMP - 7 and BMP receptors in cultured secondary follicles were quantified by real time PCR. The results showed that addition of BMP - 7 or F SH to culture medium stimulated growth of secondary follicles , while addition of both BMP - 7 and FSH was needed to significantly increase the percentage of follicles forming an antrum and the follicular levels of mRNA for both BMP - 7 and FSH - R. For BMP receptors, FSH reduced the levels of mRNA for BMPR - IA and BMP - RII in comparison with those follicles cultured in MEM alone and supplemented with BMP - 7, respectively. In conclusion , l ike FSH, BMP - 7 affect s in vitro growth of cultured secondary follicle s , but it stimulates antrum formation and expression of the mRNA s for BMP - 7 and FSH - R only in presence of both BMP - 7 and FSH . However, the levels of mRNA f or BMP - RIA and BMP - RII are reduced in follicles culture d in medium supplemented with FSH.(AU)

USO DE FLUXOFENIM EM TRIGO COMO PROTETOR AO HERBICIDA S-METOLACHLOR

ABSTRACT This work aimed to evaluate the effectiveness of fluxofenim used for seed treatment as safener in wheat, Ônix cultivar, treated with the herbicide S-metolachlor applied in pre-emergence. The study was divided in two steps. The first step consisted of an evaluation of fluxofenims safener potential for the reduction of visual symptoms of S-metolachlor injury in the field, and the treatments were S-metolachlor at 1,440 and 2,880 mL i.a. ha-1 and fluxofenim at 0, and 40 mL per 100 kg of seeds, and a control without herbicide. The second step was to evaluate glutathione S-transferase activity (GST). Herbicide phytotoxity was measured by way of visual symptoms at 3, 7, 15, and 30 days after emergence (DAE), dry matter from roots and leaves at 10 DAE. For the determination of GST activity, the canopy of plants was collected at 10 DAE and 15 days after treatment application. The wheat presented low tolerance to S-metolachlor at both rates, and fluxofenim increased S-metolachlor selectivity to wheat but not sufficiently, reducing plant population to a nonacceptable level. Gluthationa S-transferase activity for wheat increased when seeds treated with fluxofenim were submitted to S-metolachlor at 1,440 mL a.i. ha-1.

RESUMO Este trabalho teve o objetivo de avaliar a eficiência do protetor fluxofenim no tratamento de sementes de trigo, cultivar Ônix, para o aumento da seletividade do herbicida S-metolachlor aplicado em pré-emergência e determinar a atividade da enzima de detoxificação glutationa S-transferase (GST). O trabalho foi realizado em duas etapas: a primeira para a avaliação em campo da eficiência do protetor em reduzir sintomas visuais de fitointoxicação causados pelo herbicida, e a segunda para a determinação da atividade da GST, conduzida em laboratório. Os tratamentos utilizados foram: aplicação ou não do protetor na dose de 40 mL por 100 kg de sementes e a pulverização do herbicida S-metolachlor nas doses de 1.440 e 2.880 mL i.a.ha-1, além de uma testemunha sem aplicação, sendo que, na determinação da atividade da GST, se excluiu o tratamento com aplicação de 2.880 mL i.a.ha-1 de S-metolachlor. Foram comparadas a suscetibilidade ao herbicida por meio da avaliação visual de injúrias aos 3, 7, 15 e 30 dias após a emergência (DAE) e a massa seca de raiz e parte aérea aos 10 DAE. Para a determinação da atividade da GST foram coletadas amostras da parte aérea das plantas aos 15 dias após a aplicação dos tratamentos e aos 10 DAE. Apesar do fluxofenim utilizado no tratamento da cultivar de trigo conferir uma maior tolerância ao herbicida S-metolachlor, ocorreu fitointoxicação visual e redução do estande de plantas. A cultivar testada apresentou aumento na atividade da enzima GST quando da utilização do fluxofenim anteriormente à aplicação do herbicida S-metolachlor na dose de 1.440 mL i.a. ha-1.

Expression of protein and mRNA encoding Insulin Growth Factor-I (IGF-I) in goat ovarian follicles and the influence of IGF-I on in vitro development and survival of caprine preantral follicles

The aim of this study was to investigate the protein and mRNA expression levels of IGF-I and the effects of IGF-I on preantral follicle survival and development, using an in vitro goat ovarian cortical culture system. The ovaries were used for immunohistochemical localization of IGF-I protein or used to demonstrate mRNA expression of IGF-I. For the latter goal, preantral and antral follicles, cumulus-oocyte complex, mural granulosa and theca cells were collected to study mRNA expression. For in vitro studies, ovarian cortex were cultured for 1 and 7 days with MEM supplemented IGF-I (0, 1, 10, 50, 100 or 200 ng/ml). Immunohistochemical results showed strong reactions for IGF-I in oocytes and granulosa cells of all follicular stages, except in granulosa cells of primordial and primary follicles. mRNA expression analysis demonstrated a discrete increase in the production of IGF-I during the transition from primordial to the primary and secondary follicle stages. After 7 days of culture, addition of 50 ng/ml of IGF-I to the medium showed the greatest percentage of normal follicles when compared with other concentrations. Furthermore, the highest percentage of primary follicles was observed after 7 days of culture in MEM+ plus 10 and 50 ng/ml of IGF-I. Culture of ovarian tissue for 7 days in MEM+ plus 50 ng/ml of IGF-I promoted the greatest increase (P < 0.05) in follicular diameter of all of the concentrations tested. In conclusion, IGF-I protein and mRNA were expressed in all follicular categories of goat. Furthermore, IGF-I maintained preantral follicle survival, promoted primordial follicle activation and stimulated the transition from intermediate to primary follicles.(AU)

Expression of protein and mRNA encoding Insulin Growth Factor-I (IGF-I) in goat ovarian follicles and the influence of IGF-I on in vitro development and survival of caprine preantral follicles

The aim of this study was to investigate the protein and mRNA expression levels of IGF-I and the effects of IGF-I on preantral follicle survival and development, using an in vitro goat ovarian cortical culture system. The ovaries were used for immunohistochemical localization of IGF-I protein or used to demonstrate mRNA expression of IGF-I. For the latter goal, preantral and antral follicles, cumulus-oocyte complex, mural granulosa and theca cells were collected to study mRNA expression. For in vitro studies, ovarian cortex were cultured for 1 and 7 days with MEM supplemented IGF-I (0, 1, 10, 50, 100 or 200 ng/ml). Immunohistochemical results showed strong reactions for IGF-I in oocytes and granulosa cells of all follicular stages, except in granulosa cells of primordial and primary follicles. mRNA expression analysis demonstrated a discrete increase in the production of IGF-I during the transition from primordial to the primary and secondary follicle stages. After 7 days of culture, addition of 50 ng/ml of IGF-I to the medium showed the greatest percentage of normal follicles when compared with other concentrations. Furthermore, the highest percentage of primary follicles was observed after 7 days of culture in MEM+ plus 10 and 50 ng/ml of IGF-I. Culture of ovarian tissue for 7 days in MEM+ plus 50 ng/ml of IGF-I promoted the greatest increase (P < 0.05) in follicular diameter of all of the concentrations tested. In conclusion, IGF-I protein and mRNA were expressed in all follicular categories of goat. Furthermore, IGF-I maintained preantral follicle survival, promoted primordial follicle activation and stimulated the transition from intermediate to primary follicles.

A superfamília dos fatores de crescimento transformante-β e o controle da foliculogênese em mamíferos / Transforming growth factors -β superfamily members and control of folliculogenesis in mammals

A foliculogênese ovariana é um processo complexo caracterizado pela formação, crescimento e maturação folicular. Esta revisão discute a localização, os sítios de ação e as funções de fatores da família TGF-β [proteínas morfogenéticas ósseas dos tipos 2 (BMP-2), 4 (BMP-4), 6 (BMP-6), 7 (BMP-7), 15 (BMP-15), fator de diferenciação do crescimento-9 (GDF-9), ativina-A, inibina, hormônio anti-Mülleriano (AMH) e fator de crescimento transformante-ß (TGF-ß)] na regulação da foliculogênese em mamíferos. Alguns fatores, como o AMH, atuam inibindo o crscimento dos folículos primordiais e reduzindo a sensibilidadade dos folículos em crescimento ao FSH, enquanto vários outros (BMP-2, 4, 7, 15, GDF-9, ativina-A e TGF-ß) estimulam o crecimento folicular. Em geral, a foliculogênese é regulada por uma complexa interação desses fatores de crescimento com as gonadotrofinas.(AU)

Ovarian folliculogenesis is a complex process that includes follicular formation, growth and maturation. This review discuss the localization and functions of TGF-β family members [bone morphogenetic proteins 2 (BMP-2), 4 (BMP-4), 6 (BMP-6), 7 (BMP-7), 15 (BMP-15), growth and differentiation factor-9 (GDF-9), activin-A, inibin, anti-Müllerian hormony (AMH) and transforming growth factor-ß (TGF-ß)] in the regulation of ovarian folliculogenesis in mammals. Some of these factors, such as AMH, inhibit growth of primoridal follicles and reduce sensitity of growing follicles to FSH, while various others (BMP-2, 4, 7, 15, GDF-9, activina-A and TGF-ß) stimulate follicular growth. In general, folliculogenesis is regulated by a complex interaction of these factors with gonadotrophins.(AU)

A superfamília dos fatores de crescimento transformante-β e o controle da foliculogênese em mamíferos / Transforming growth factors -β superfamily members and control of folliculogenesis in mammals

A foliculogênese ovariana é um processo complexo caracterizado pela formação, crescimento e maturação folicular. Esta revisão discute a localização, os sítios de ação e as funções de fatores da família TGF-β [proteínas morfogenéticas ósseas dos tipos 2 (BMP-2), 4 (BMP-4), 6 (BMP-6), 7 (BMP-7), 15 (BMP-15), fator de diferenciação do crescimento-9 (GDF-9), ativina-A, inibina, hormônio anti-Mülleriano (AMH) e fator de crescimento transformante-ß (TGF-ß)] na regulação da foliculogênese em mamíferos. Alguns fatores, como o AMH, atuam inibindo o crscimento dos folículos primordiais e reduzindo a sensibilidadade dos folículos em crescimento ao FSH, enquanto vários outros (BMP-2, 4, 7, 15, GDF-9, ativina-A e TGF-ß) estimulam o crecimento folicular. Em geral, a foliculogênese é regulada por uma complexa interação desses fatores de crescimento com as gonadotrofinas.

Ovarian folliculogenesis is a complex process that includes follicular formation, growth and maturation. This review discuss the localization and functions of TGF-β family members [bone morphogenetic proteins 2 (BMP-2), 4 (BMP-4), 6 (BMP-6), 7 (BMP-7), 15 (BMP-15), growth and differentiation factor-9 (GDF-9), activin-A, inibin, anti-Müllerian hormony (AMH) and transforming growth factor-ß (TGF-ß)] in the regulation of ovarian folliculogenesis in mammals. Some of these factors, such as AMH, inhibit growth of primoridal follicles and reduce sensitity of growing follicles to FSH, while various others (BMP-2, 4, 7, 15, GDF-9, activina-A and TGF-ß) stimulate follicular growth. In general, folliculogenesis is regulated by a complex interaction of these factors with gonadotrophins.

Mechanisms of atresia in ovarian follicles

There are thousands to millions of follicles in the mammalian ovary, and the majority (99.9%) are eliminated by a process known as atresia. This phenomenon occurs in any stage of follicular development, through an apoptotic manner or the degenerative process of necrosis. Thus, a better understanding of the mechanisms involved in atresia is necessary to avoid the great follicular loss that occurs in vivo and to maximize female reproductive potential. The present review focuses on aspects related to follicular population and atresia, mechanisms of atresia (apoptosis or the degenerative process of necrosis), techniques used to analyze atresia in ovarian follicles, and the occurrence of the atretic process during different follicular stages.(AU)

Mechanisms of atresia in ovarian follicles

There are thousands to millions of follicles in the mammalian ovary, and the majority (99.9%) are eliminated by a process known as atresia. This phenomenon occurs in any stage of follicular development, through an apoptotic manner or the degenerative process of necrosis. Thus, a better understanding of the mechanisms involved in atresia is necessary to avoid the great follicular loss that occurs in vivo and to maximize female reproductive potential. The present review focuses on aspects related to follicular population and atresia, mechanisms of atresia (apoptosis or the degenerative process of necrosis), techniques used to analyze atresia in ovarian follicles, and the occurrence of the atretic process during different follicular stages.

Característica histológica, ultra-estrutural e produção de nitrito de folículos pré-antrais caprinos cultivados in vitro na ausência ou presença de soro / Histological and ultrastructural feature and nitrite production of caprine preantral follicles in vitro cultured in the presence or absence of serum

Avaliou-se o efeito da adição de diferentes tipos e concentrações de soro sobre o desenvolvimento e a sobrevivência de folículos ovarianos pré-antrais (FOPA) caprinos in vitro. Além disso, verificou-se a relação entre as concentrações de nitrito presentes no meio de cultivo e a viabilidade folicular. Cada par ovariano foi dividido em 29 fragmentos, sendo um destinado ao controle. Os fragmentos foram cultivados por um ou sete dias em meio essencial mínimo suplementado (MEM+) ou MEM+ com diferentes concentrações (10 ou 20 por cento) de soro fetal bovino (SFB), soro de cabra em estro (SCE) ou soro de cabra em diestro (SCD). Na análise morfológica após sete dias, apenas o tratamento com 10 por cento de SFB apresentou percentual de FOPA normais similar ao MEM+ (P>0,05). A análise ultra-estrutural dos folículos cultivados por sete dias com MEM+ ou MEM+ com 10 por cento de SFB mostrou danos oocitários, porém células da granulosa normais. A análise do meio de cultivo revelou correlação positiva entre a viabilidade folicular e a produção de nitrito. A suplementação com soro não melhorou a viabilidade de FOPA e a concentração de nitrito no meio de cultivo funcionou como um indicador da viabilidade das células da granulosa de FOPA caprinos cultivados in vitro.(AU)

The effect of the addition of different types and concentrations of sera on the viability and development of caprine preantal follicles (PAF) in vitro cultured was analyzed. In addition, it was evaluated the correlation between nitrite concentrations in culture medium and folicular viability. Each ovarian pair was divided in 29 fragments and one was used as control. The fragments were cultured for one or seven days in minimal essential medium (MEM+) or MEM+ with different concentrations of (10 or 20 percent) bovine fetal serum (BFS), estrous goat serum (EGS), or diestrous goat serum (DGS). After seven days, the morphological analysis showed that only the treatment with 10 percent BFS maintained the percentage of normal PAF similar to MEM+ (P>0.05). The ultrastructural analysis of follicles cultured for seven days in MEM+ or MEM+ with 10 percent BFS showed some oocyte damage, although the granulosa cells were normal. Analysis of culture medium revealed a positive correlation between follicular viability and nitrite production. Supplementation with serum did not improve the viability of PAF and nitrite levels in culture medium served as an indicator of viability of granulose cells from caprine PAF in vitro cultured.(AU)

Conservação de folículos pré-antrais bovinos em solução salina 0.9 por cento ou TCM 199 / Preservation of bovine preantral follicles in 0.9 percent saline solution or TCM 199

Investigou-se a eficiência da solução salina 0,9 por cento (SS) e TCM 199 na conservação de folículos pré-antrais (FOPA) bovinos in situ em diferentes temperaturas e tempos de incubação. Cada par ovariano foi dividido em 25 fragmentos. Um fragmento foi escolhido aleatoriamente e fixado imediatamente após a coleta (controle). Os demais foram distribuídos em tubos contendo SS ou TCM 199 a 4, 20 ou 39ºC por 2, 4, 12 ou 24h. A análise histológica mostrou que a conservação a 4ºC em ambas as soluções manteve a porcentagem de FOPA normais similar ao controle. A conservação em SS a 20ºC por 12 ou 24h, TCM 199 a 20ºC por 24h e em ambas as soluções a 39ºC a partir de 2h aumentou (P<0,05) a porcentagem de FOPA degenerados comparada à porcentagem de folículos-controle. Em ambas as soluções, independente do tempo de incubação, a porcentagem de folículos normais, após conservação a 39ºC, foi (P<0,05) menor que a obtida com 4 e 20ºC. FOPA bovinos podem ser conservados eficientemente a 4ºC por até 24h em ambas as soluções, e a 20ºC por 4 e 12h em SS e TCM 199, respectivamente.(AU)

The efficiency of 0.9 percent saline solution (SS) and TCM 199 on the preservation of bovine preantral follicles (PF) in situ at different temperatures and incubation times was investigated. Each ovarian pair was divided into 25 fragments. One fragment was taken randomly and immediately fixed (control). The other fragments were distributed in tubes containing SS or TCM 199 at 4, 20 or 39ºC for 2, 4, 12 or 24h. The histological analysis showed that the storage at 4ºC in both solutions kept the percentage of normal follicles similar to control values. Preservation in SS at 20ºC for 12 or 24h, TCM 199 at 20ºC for 24h and in both solutions at 39ºC from 2 h onward (P<0.05) increased the percentage of degenerated follicles when compared with control. In both solutions, independent of incubation time, the percentage of normal follicles observed at 39ºC was (P<0.05) lower them those observed at 4 and 20ºC. Bovine PF can be preserved efficiently at 4ºC for up to 24h in both solutions, at 20ºC for 4 and 12h in SS and TCM 199, respectively.(AU)