Impact of high-fat diet consumption during prolonged period of pregnancy on placenta structures and umbilical vascular growth in goats

This study aimed to verify the impact of high-fat diet consumption for a prolonged period on oxidative stress, fetal growth, umbilical vascular system, and placental structures in pregnant goats. Twenty-two pregnant goats were grouped into the control diet (n= 11) and fat diet (n = 11). Flaxseed meal was added to the fat diet, replacing the corn grain of concentrate, from gestational day 100 to delivery date. Diets were isonitrogenous and isoenergetic, differing in fat content (2.8% vs. 6.3% dry matter). The fat group showed higher feed intake and total plasma lipid levels than the control group (P < 0.001). No difference was found in placentome, and umbilical vascular development. Fat diet-fed goats exhibited a lower systolic peak in the umbilical artery. At delivery, placental traits were similar with the exception of the cotyledon width (P = 0.0075), which was smaller in the fat group and cotyledon surface (P = 0.0047) for multiple pregnancy of fat diet. Cotyledonary epithelium showed more intense staining of lipid droplets and a greater area for lipofuscin staining in the fat group compared to control group (P < 0.001). The mean live weight of the kids was lower in the fat group in the first week after delivery than in control group. Thus, in goats, the continuous administration of a high-fat diet during pregnancy does not appear to modify the fetal-maternal vascular structures but has an impact on a part of the placental structure; therefore, its use must be carefully evaluated.(AU)

Efeitos da vitrificação na preservação morfológica do tecido testicular de gato doméstico / Vitrification effects during morphological preservation of testicular tissue from domestic cat

This study aimed to evaluate the effect of domestic cats (Felis Catus) testicular parenchyma vitrification by Ovarian Tissue Cryosystem and conventional straw. Three (n=3) adult cats were submitted to routine orchiectomy. For the vitrification, the samples were exposed to equilibrium solution composed by RPMI, containing 20% of ethylene glycol (EG) and 0,1M of sucrose at 20 °C, for 3 minutes. Subsequently, exposed to vitrification solution, containing RPMI added to 40% of EG and 0,1 M of sucrose at 20 °C, for 2 minutes. After devitrification, 10 seminiferous tubules of each treatment were analyzed by histology assay. The viability of spermatic and Sertolicells were analysed with light histology, as well as the seminiferous tubules morphometry. The vitrified groups were inferior to the control group in the morphologically integral cells analysis. However, the OTC was superior to straw in terms of morphological preservation of the germinative cells. Nevertheless, in morphometric analysis there was no statistical difference between the treatments (control, OTC and straw). Therefore, the vitrification in OTC method showed better results than vitrification in straw based on histological evaluation of germ and Sertoli cells of domestic cats.

Efeitos da vitrificação na preservação morfológica do tecido testicular de gato doméstico / Vitrification effects during morphological preservation of testicular tissue from domestic cat

This study aimed to evaluate the effect of domestic cats (Felis Catus) testicular parenchyma vitrification by Ovarian Tissue Cryosystem and conventional straw. Three (n=3) adult cats were submitted to routine orchiectomy. For the vitrification, the samples were exposed to equilibrium solution composed by RPMI, containing 20% of ethylene glycol (EG) and 0,1M of sucrose at 20 °C, for 3 minutes. Subsequently, exposed to vitrification solution, containing RPMI added to 40% of EG and 0,1 M of sucrose at 20 °C, for 2 minutes. After devitrification, 10 seminiferous tubules of each treatment were analyzed by histology assay. The viability of spermatic and Sertolicells were analysed with light histology, as well as the seminiferous tubules morphometry. The vitrified groups were inferior to the control group in the morphologically integral cells analysis. However, the OTC was superior to straw in terms of morphological preservation of the germinative cells. Nevertheless, in morphometric analysis there was no statistical difference between the treatments (control, OTC and straw). Therefore, the vitrification in OTC method showed better results than vitrification in straw based on histological evaluation of germ and Sertoli cells of domestic cats.(AU)

Criopreservação de tecido ovariano e/ou folículos pré-antrais: uma alternativa para salvaguardar o material genético e a fertilidade de ovelhas e cabras valiosas / Cryopreservation of ovarian tissue and/or preantral follicles: an alternative to safeguard the genetic material and fertility of valuable sheep and goats

A redução da biodiversidade tem levado a uma preocupação emergencial frente a conservação do material biológico de animais geneticamente valiosos. Para tanto, a implantação de bancos de germoplasma, como embriões, gametas e tecido gonadal e somáticos, tem sido uma alternativa para auxiliar na manutenção da biodiversidade. No tocante ao material genético de fêmeas, a criopreservação de folículos pré-antrais isolados ou inclusos no tecido ovariano associada ao uso de tecnologias de reprodução assistida, como cultivo, fertilização in vitro e produção de embriões in vitro, poderá auxiliar na conservação da fertilidade de animais domésticos de interesse econômico com dificuldades reprodutivas ou animais ameaçados de extinção. Além disso, a criopreservação de tecido ovariano seguida de transplante pode ser uma alternativa promissora, uma vez que permite a restauração da função ovariana e reprodutiva. Estudos realizados em humanos relataram o nascimento de 130 indivíduos após o transplante de tecido ovariano previamente criopreservado. Apesar desse sucesso, a criopreservação de ovário ainda é considerada uma técnica experimental. Especialmente em caprinos e ovinos, a grande maioria dos estudos tem usado essas espécies como modelo experimental para a espécie humana. Nessas espécies, o sucesso da criopreservação de folículos ovarianos já foi evidenciado, o que nos dá esperança para o uso dessa tecnologia, vislumbrando, não somente a conservação do material genético, mas a obtenção de embriões e nascimento de crias mesmo após a morte de um animal geneticamente valioso. Assim, todos os esforços atuais estão voltados para a avaliação adequada da qualidade de protocolos de criopreservação que assegurem que esses recursos genéticos permaneçam como parte funcional dos sistemas de produção e conservação das espécies.(AU)

Reducing biodiversity has led to an emergency concern over the conservation of biological material from genetically valuable animals. Therefore, the establishment of gene banks, such as embryos, gametes and somatic and ovarian tissue has been an alternative to assist in maintaining biodiversity. Concerning the genetic material of females, the cryopreservation of preantral follicles isolated or included in the ovarian tissue associated with the use of assisted reproduction technologies, such as culture, in vitro fertilization and in vitro embryo production, may help to preserve the fertility of domestic animals of economic interest with reproductive difficulties or animals threatened with extinction. In addition, cryopreservation of ovarian tissue followed by transplantation may be a promising alternative, since it allows the restoration of ovarian and reproductive function. Studies in humans have reported the birth of 130 individuals after previously cryopreserved ovarian tissue transplantation. Despite this success, ovary cryopreservation is still considered an experimental technique. Especially in goats and sheep, the vast majority of studies have used these species as an experimental model for the human species. In these species, the success of cryopreservation of ovarian follicles has already been shown, which gives us hope for the use of this technology, noting not only the conservation of the genetic material, but the obtaining of embryos and the birth of youngsters even after the death of a genetically valuable animal. Thus, all current efforts are focused on the proper evaluation of the quality of cryopreservation protocols that ensure that these genetic resources remain as a functional part of the systems of production and conservation of the species.(AU)

Criopreservação de tecido ovariano e/ou folículos pré-antrais: uma alternativa para salvaguardar o material genético e a fertilidade de ovelhas e cabras valiosas / Cryopreservation of ovarian tissue and/or preantral follicles: an alternative to safeguard the genetic material and fertility of valuable sheep and goats

A redução da biodiversidade tem levado a uma preocupação emergencial frente a conservação do material biológico de animais geneticamente valiosos. Para tanto, a implantação de bancos de germoplasma, como embriões, gametas e tecido gonadal e somáticos, tem sido uma alternativa para auxiliar na manutenção da biodiversidade. No tocante ao material genético de fêmeas, a criopreservação de folículos pré-antrais isolados ou inclusos no tecido ovariano associada ao uso de tecnologias de reprodução assistida, como cultivo, fertilização in vitro e produção de embriões in vitro, poderá auxiliar na conservação da fertilidade de animais domésticos de interesse econômico com dificuldades reprodutivas ou animais ameaçados de extinção. Além disso, a criopreservação de tecido ovariano seguida de transplante pode ser uma alternativa promissora, uma vez que permite a restauração da função ovariana e reprodutiva. Estudos realizados em humanos relataram o nascimento de 130 indivíduos após o transplante de tecido ovariano previamente criopreservado. Apesar desse sucesso, a criopreservação de ovário ainda é considerada uma técnica experimental. Especialmente em caprinos e ovinos, a grande maioria dos estudos tem usado essas espécies como modelo experimental para a espécie humana. Nessas espécies, o sucesso da criopreservação de folículos ovarianos já foi evidenciado, o que nos dá esperança para o uso dessa tecnologia, vislumbrando, não somente a conservação do material genético, mas a obtenção de embriões e nascimento de crias mesmo após a morte de um animal geneticamente valioso. Assim, todos os esforços atuais estão voltados para a avaliação adequada da qualidade de protocolos de criopreservação que assegurem que esses recursos genéticos permaneçam como parte funcional dos sistemas de produção e conservação das espécies.

Reducing biodiversity has led to an emergency concern over the conservation of biological material from genetically valuable animals. Therefore, the establishment of gene banks, such as embryos, gametes and somatic and ovarian tissue has been an alternative to assist in maintaining biodiversity. Concerning the genetic material of females, the cryopreservation of preantral follicles isolated or included in the ovarian tissue associated with the use of assisted reproduction technologies, such as culture, in vitro fertilization and in vitro embryo production, may help to preserve the fertility of domestic animals of economic interest with reproductive difficulties or animals threatened with extinction. In addition, cryopreservation of ovarian tissue followed by transplantation may be a promising alternative, since it allows the restoration of ovarian and reproductive function. Studies in humans have reported the birth of 130 individuals after previously cryopreserved ovarian tissue transplantation. Despite this success, ovary cryopreservation is still considered an experimental technique. Especially in goats and sheep, the vast majority of studies have used these species as an experimental model for the human species. In these species, the success of cryopreservation of ovarian follicles has already been shown, which gives us hope for the use of this technology, noting not only the conservation of the genetic material, but the obtaining of embryos and the birth of youngsters even after the death of a genetically valuable animal. Thus, all current efforts are focused on the proper evaluation of the quality of cryopreservation protocols that ensure that these genetic resources remain as a functional part of the systems of production and conservation of the species.

Vitrification of ovarian tissue from non-human primates

Background: One of the strategies to preserve genetic material from nonhuman primates (NHP) consists in the implementation of germplasm banks, for future application in reproductive biotechniques, as well as for biomedical research. Based on the success rates achieved in human, there is a prominent possibility to succeed also with NHP. However, studies with NHP are still scarce, especially regarding the cryopreservation of ovarian tissue.Review: Neotropical non-human primates, especially males, have been used in research related to reproductive biotechniques in Brazil. Regarding research on female reproduction and ovarian tissue preservation, most studies were performed using domestic animals as models. Current concepts and controversies in the restoration of gametes in adult females does not exclude the needs to preserve ovarian tissue. Importantly, ovarian tissue can be collected and preserved even after the death of the donors, being applied when finding dead females. Furthermore, collection of ovarian biopsies is also feasible and will not affect reproductive function. Among the cryopreservation methods, the vitrification has been indicated due to practical logistic, as well as because it will avoid the formation of large intracellular ice crystals, and it is claimed that ovarian stromal damage will be decreased under vitrification. Considering the number of threatened primate species and the needs to preserve their habitat, but also their gametes, development of preservation protocols are needed. Among the procedures, vitrification appears as a practical method to be applied in the near future. Although a low number of studies is reported, most of them were performed in the recent years. In this context, this article reviews recent information on the vitrification of ovarian tissue of non-human primates. Due to the limited number of studies in these species, observed data are compared with the literature in domestic and human mammals.[...]

Vitrification of ovarian tissue from non-human primates

Background: One of the strategies to preserve genetic material from nonhuman primates (NHP) consists in the implementation of germplasm banks, for future application in reproductive biotechniques, as well as for biomedical research. Based on the success rates achieved in human, there is a prominent possibility to succeed also with NHP. However, studies with NHP are still scarce, especially regarding the cryopreservation of ovarian tissue.Review: Neotropical non-human primates, especially males, have been used in research related to reproductive biotechniques in Brazil. Regarding research on female reproduction and ovarian tissue preservation, most studies were performed using domestic animals as models. Current concepts and controversies in the restoration of gametes in adult females does not exclude the needs to preserve ovarian tissue. Importantly, ovarian tissue can be collected and preserved even after the death of the donors, being applied when finding dead females. Furthermore, collection of ovarian biopsies is also feasible and will not affect reproductive function. Among the cryopreservation methods, the vitrification has been indicated due to practical logistic, as well as because it will avoid the formation of large intracellular ice crystals, and it is claimed that ovarian stromal damage will be decreased under vitrification. Considering the number of threatened primate species and the needs to preserve their habitat, but also their gametes, development of preservation protocols are needed. Among the procedures, vitrification appears as a practical method to be applied in the near future. Although a low number of studies is reported, most of them were performed in the recent years. In this context, this article reviews recent information on the vitrification of ovarian tissue of non-human primates. Due to the limited number of studies in these species, observed data are compared with the literature in domestic and human mammals.[...](AU)

Toxicity effect of Auxemma oncocalyx fraction and its active principle oncocalyxone A on in vitro culture of caprine secondary follicles and in vitro oocyte maturation / Efeito da toxicidade da fração da Auxemma oncocalyx e seu princípio ativo oncocalyxona A no cultivo in vitro de folículos secundários e na maturação in vitro de oócitos de caprinos

The extract of Auxemma oncocalyx (A. oncocalyx) and its main component, oncocalyxone A (onco A), possess anti-tumoral activity that may affect fertility. There is limited literature on the action of these substances regarding caprine folliculogenesis. In this study, we evaluated the effect of A. oncocaly and onco A on the in vitro culture of isolated secondary follicles (Experiment 1) and on the in vitro maturation (IVM) of oocytes from caprine antral follicles grown in vivo (Experiment 2). Isolated secondary follicles were distributed in six groups: the non-cultured control was immediately fixed in 4% paraformaldehyde. The remaining follicles were cultured for 7 days in α-minimal essential medium (α-MEM+ ) alone (control) or with dimethyl sulfoxide (DMSO), doxorubicin (DXR), A. oncocalyx, or onco A. After culture, the follicles were evaluated for antrum formation, growth rate, apoptosis (TUNEL), cellular proliferation (PCNA), as well as the expression of BCL2 and BAX. In addition, cumulus oocyte complexes (COCs) were aspirated and allocated into five treatments for IVM: control, cultured only in maturation base medium (TCM 199+ ); or supplemented with DMSO; DXR; A. oncocalyx or onco A. After IVM, oocyte chromatin configuration and viability were assessed. After 7 days of culture, a reduction was noted in the percent of morphologically intact follicles, antrum formation, growth rate, and numbers of PCNApositive granulosa cells (P < 0.05). After culture, the DXR treatment showed a higher percent of TUNELpositive follicles and relative BAX:BCL2 mRNA ratio’s (P < 0.05). After IVM of the COCs, DXR, A. oncocalyx, and onco A treatments showed a greater percent (P < 0.05) of abnormal oocytes and a lower percent of viable oocytes as compared with the control group (P < 0.05)...

O extrato da Auxemma oncocalyx (A. oncocalyx) e seu componente, Oncocalyxona A (onco A), possui atividade antitumoral, podendo afetar a fertilidade. Entretanto, estudos sobre a ação dessas substâncias em relação à foliculogênese caprina são desconhecidos. O objetivo desse estudo foi avaliar o efeito da A. oncocalyx e onco A no cultivo in vitro de folículos secundários isolados (Experimento 1) e na maturação in vitro (MIV) de oócitos de folículos antrais caprinos crescidos in vivo (Experimento 2). Folículos secundários isolados foram distribuídos em seis grupos, em que o controle não-cultivado foi imediatamente fixado em paraformaldeído 4%. Os folículos restantes foram cultivados durante 7 dias em α-MEM+ sozinho (controle) ou suplementado com DMSO, doxorrubicina (DXR), A. oncocalyx ou onco A. Após o cultivo, os folículos foram avaliados quanto à formação de antro, taxa de crescimento, apoptose (TUNEL) e proliferação celular (PCNA), bem como a expressão dos genes BCL2 e BAX. Além disso, os complexos cumulus-oócitos (CCOs) foram aspirados e distribuídos em cinco tratamentos para MIV: o controle em meio de maturação (TCM 199+), e os demais tratamentos suplementados com DMSO, DXR, A. oncocalyx ou onco A. Depois da MIV, a configuração da cromatina e viabilidade oocitária foram avaliadas. Após 7 dias de cultivo, observou-se redução na percentagem de folículos morfologicamente intactos, na formação de antro, na taxa de crescimento e no número de células PCNA positivas (P < 0,05). Depois do cultivo, no tratamento DXR foi observada maior percentagem de folículos TUNEL positivos (P < 0,05) e também aumento na taxa de RNAm BAX: BCL2 (P < 0,05). Após MIV dos CCOs, nos tratamentos com DXR, A. oncocalyx e onco A, observou-se maior (P < 0,05) percentagem de oócitos anormais e menor de oócitos viáveis quando comparados ao grupo controle (P < 0,05)...

Toxicity effect of Auxemma oncocalyx fraction and its active principle oncocalyxone A on in vitro culture of caprine secondary follicles and in vitro oocyte maturation / Efeito da toxicidade da fração da Auxemma oncocalyx e seu princípio ativo oncocalyxona A no cultivo in vitro de folículos secundários e na maturação in vitro de oócitos de caprinos

The extract of Auxemma oncocalyx (A. oncocalyx) and its main component, oncocalyxone A (onco A), possess anti-tumoral activity that may affect fertility. There is limited literature on the action of these substances regarding caprine folliculogenesis. In this study, we evaluated the effect of A. oncocaly and onco A on the in vitro culture of isolated secondary follicles (Experiment 1) and on the in vitro maturation (IVM) of oocytes from caprine antral follicles grown in vivo (Experiment 2). Isolated secondary follicles were distributed in six groups: the non-cultured control was immediately fixed in 4% paraformaldehyde. The remaining follicles were cultured for 7 days in α-minimal essential medium (α-MEM+ ) alone (control) or with dimethyl sulfoxide (DMSO), doxorubicin (DXR), A. oncocalyx, or onco A. After culture, the follicles were evaluated for antrum formation, growth rate, apoptosis (TUNEL), cellular proliferation (PCNA), as well as the expression of BCL2 and BAX. In addition, cumulus oocyte complexes (COCs) were aspirated and allocated into five treatments for IVM: control, cultured only in maturation base medium (TCM 199+ ); or supplemented with DMSO; DXR; A. oncocalyx or onco A. After IVM, oocyte chromatin configuration and viability were assessed. After 7 days of culture, a reduction was noted in the percent of morphologically intact follicles, antrum formation, growth rate, and numbers of PCNApositive granulosa cells (P < 0.05). After culture, the DXR treatment showed a higher percent of TUNELpositive follicles and relative BAX:BCL2 mRNA ratios (P < 0.05). After IVM of the COCs, DXR, A. oncocalyx, and onco A treatments showed a greater percent (P < 0.05) of abnormal oocytes and a lower percent of viable oocytes as compared with the control group (P < 0.05)...(AU)

O extrato da Auxemma oncocalyx (A. oncocalyx) e seu componente, Oncocalyxona A (onco A), possui atividade antitumoral, podendo afetar a fertilidade. Entretanto, estudos sobre a ação dessas substâncias em relação à foliculogênese caprina são desconhecidos. O objetivo desse estudo foi avaliar o efeito da A. oncocalyx e onco A no cultivo in vitro de folículos secundários isolados (Experimento 1) e na maturação in vitro (MIV) de oócitos de folículos antrais caprinos crescidos in vivo (Experimento 2). Folículos secundários isolados foram distribuídos em seis grupos, em que o controle não-cultivado foi imediatamente fixado em paraformaldeído 4%. Os folículos restantes foram cultivados durante 7 dias em α-MEM+ sozinho (controle) ou suplementado com DMSO, doxorrubicina (DXR), A. oncocalyx ou onco A. Após o cultivo, os folículos foram avaliados quanto à formação de antro, taxa de crescimento, apoptose (TUNEL) e proliferação celular (PCNA), bem como a expressão dos genes BCL2 e BAX. Além disso, os complexos cumulus-oócitos (CCOs) foram aspirados e distribuídos em cinco tratamentos para MIV: o controle em meio de maturação (TCM 199+), e os demais tratamentos suplementados com DMSO, DXR, A. oncocalyx ou onco A. Depois da MIV, a configuração da cromatina e viabilidade oocitária foram avaliadas. Após 7 dias de cultivo, observou-se redução na percentagem de folículos morfologicamente intactos, na formação de antro, na taxa de crescimento e no número de células PCNA positivas (P < 0,05). Depois do cultivo, no tratamento DXR foi observada maior percentagem de folículos TUNEL positivos (P < 0,05) e também aumento na taxa de RNAm BAX: BCL2 (P < 0,05). Após MIV dos CCOs, nos tratamentos com DXR, A. oncocalyx e onco A, observou-se maior (P < 0,05) percentagem de oócitos anormais e menor de oócitos viáveis quando comparados ao grupo controle (P < 0,05)...(AU)

Platelet-derived growth factor-BB (PDGF-BB) improves follicular survival, oocyte and follicular diameters, in a dose-dependent manner, after the in vitro culture of goat preantral follicles enclosed in ovarian tissue fragments

The aims of this study were to investigate the effects of different concentrations of Platelet-derived growth factor-BB (PDGF-BB) on the survival, activation, levels of ROS, and growth of goat preantral follicles enclosed in ovarian tissue. For this, ovarian fragments were cultured for 7 days in Alpha Minimum Essential Medium (α-MEM+ ) with or without PDGF-BB (0, 25, 50 and 100 ng/ml). The results showed that both the 25 ng/ml PDGF and the 50 ng/ml PDGF treatments maintained the percentage of morphologically normal follicles from day 1 to day 7. In addition, the 25 ng/ml PDGF treatment showed a significantly higher percentage of morphologically normal follicles when compared to the other treatments. At day 7, greater (P < 0.05) follicular and oocyte diameters were observed in the 25 ng/ml PDGF and the 50 ng/ml PDGF treatments when compared to the cultured control treatment. On day 7 of culture, all the treatments tested had a significant increase in the percentage of developing follicles when compared to the non-cultured control. However, the percentage of follicle activation, as well as ROS production, were similar (P < 0.05) among the treatments, irrespective of culture time. In conclusion, PDGF-BB improved, in a concentration-dependent manner, follicular survival as well as oocyte and follicular diameter after in vitro culture of goat preantral follicle-enclosed in ovarian tissue fragments.

Platelet-derived growth factor-BB (PDGF-BB) improves follicular survival, oocyte and follicular diameters, in a dose-dependent manner, after the in vitro culture of goat preantral follicles enclosed in ovarian tissue fragments

The aims of this study were to investigate the effects of different concentrations of Platelet-derived growth factor-BB (PDGF-BB) on the survival, activation, levels of ROS, and growth of goat preantral follicles enclosed in ovarian tissue. For this, ovarian fragments were cultured for 7 days in Alpha Minimum Essential Medium (α-MEM+ ) with or without PDGF-BB (0, 25, 50 and 100 ng/ml). The results showed that both the 25 ng/ml PDGF and the 50 ng/ml PDGF treatments maintained the percentage of morphologically normal follicles from day 1 to day 7. In addition, the 25 ng/ml PDGF treatment showed a significantly higher percentage of morphologically normal follicles when compared to the other treatments. At day 7, greater (P < 0.05) follicular and oocyte diameters were observed in the 25 ng/ml PDGF and the 50 ng/ml PDGF treatments when compared to the cultured control treatment. On day 7 of culture, all the treatments tested had a significant increase in the percentage of developing follicles when compared to the non-cultured control. However, the percentage of follicle activation, as well as ROS production, were similar (P < 0.05) among the treatments, irrespective of culture time. In conclusion, PDGF-BB improved, in a concentration-dependent manner, follicular survival as well as oocyte and follicular diameter after in vitro culture of goat preantral follicle-enclosed in ovarian tissue fragments.(AU)

Criopreservação do tecido ovariano visando restaurar a fertilidade humana

A criopreservação e transplante do tecido ovariano representa uma técnica em potencial para apreservação e restauração da fertilidade feminina, especialmente de mulheres jovens que se submetem atratamentos gonadotóxicos como os quimioterápicos, usados contra o câncer. Embora, o transplante de tecidoovariano fresco ou criopreservado tenha resultado no nascimento de indivíduos em diferentes espécies, comocamundongos, ovinos e humanos, os riscos de reintrodução de células cancerosas após o tratamento, temlimitado o uso clínico. Desta forma, o cultivo in vitro de folículos pré-antrais após criopreservação do tecidoovariano pode ser uma alternativa promissora para a preservação da fertilidade em casos extremos. Acombinação destas técnicas é capaz de salvaguardar a fertilidade de pacientes que sofrem de câncer, comotambém permite a preservação do germoplasma de animais de alto valor comercial ou sob risco de extinção. Noentanto, muitos desafios ainda necessitam ser superados, especialmente no que se refere à utilização de tecidoovariano previamente criopreservado em animais de produção.(AU)

Criopreservação do tecido ovariano visando restaurar a fertilidade humana

A criopreservação e transplante do tecido ovariano representa uma técnica em potencial para apreservação e restauração da fertilidade feminina, especialmente de mulheres jovens que se submetem atratamentos gonadotóxicos como os quimioterápicos, usados contra o câncer. Embora, o transplante de tecidoovariano fresco ou criopreservado tenha resultado no nascimento de indivíduos em diferentes espécies, comocamundongos, ovinos e humanos, os riscos de reintrodução de células cancerosas após o tratamento, temlimitado o uso clínico. Desta forma, o cultivo in vitro de folículos pré-antrais após criopreservação do tecidoovariano pode ser uma alternativa promissora para a preservação da fertilidade em casos extremos. Acombinação destas técnicas é capaz de salvaguardar a fertilidade de pacientes que sofrem de câncer, comotambém permite a preservação do germoplasma de animais de alto valor comercial ou sob risco de extinção. Noentanto, muitos desafios ainda necessitam ser superados, especialmente no que se refere à utilização de tecidoovariano previamente criopreservado em animais de produção.

Cultivo in vitro de folículos pré-antrais: principais substâncias reguladoras, vias de sinalização e avanços nas espécies murina, bovina, ovina e caprina / In vitro culture of preantral follicles: main regulatory factors, signaling pathways and advances in murine, bovine, ovine and caprine

A regulação da foliculogênese é um processo complexo regulado por vários fatores intra e extraovarianos. A resposta das células ovarianas ao estímulo produzido por esses fatores depende da transdução de sinais no interior das células através de várias vias de sinalização. A interação entre as diversas vias de sinalização celular e a descoberta constante de novas vias demonstram a complexidade desse processo. A presente revisão se propõe a descrever os principais fatores reguladores da foliculogênese, seus receptores e as vias de sinalização celular destacando pontos de interação entre elas. Em adição, uma análise crítica dos principais resultados obtidos com o cultivo in vitro de folículos ovarianos murinos, bovinos, caprinos e ovinos levando-se em consideração as substâncias presentes nos meios de cultivo utilizados e as prováveis vias de sinalização celular empregadas é apresentada na presente revisão.

Folliculogenesis is regulated by a complex process, which involves several intra- and extraovarian factors. The response of the ovarian cells to those factors depends on the signal transduction inside the cells through several signaling pathways. The interaction of different signaling pathways and discovery of new pathways demonstrate the complexity of folliculogenesis. Therefore, this review will highlight the main regulatory factors that control folliculogenesis, their receptors and sharing signaling pathways. Moreover, a critical analysis about the main results from in vitro follicle culture studies in murine, bovine, caprine, and ovine, focusing on the medium supplements and the interactions of their signaling pathways will be presented.

Cultivo in vitro de folículos pré-antrais: principais substâncias reguladoras, vias de sinalização e avanços nas espécies murina, bovina, ovina e caprina / In vitro culture of preantral follicles: main regulatory factors, signaling pathways and advances in murine, bovine, ovine and caprine

A regulação da foliculogênese é um processo complexo regulado por vários fatores intra e extraovarianos. A resposta das células ovarianas ao estímulo produzido por esses fatores depende da transdução de sinais no interior das células através de várias vias de sinalização. A interação entre as diversas vias de sinalização celular e a descoberta constante de novas vias demonstram a complexidade desse processo. A presente revisão se propõe a descrever os principais fatores reguladores da foliculogênese, seus receptores e as vias de sinalização celular destacando pontos de interação entre elas. Em adição, uma análise crítica dos principais resultados obtidos com o cultivo in vitro de folículos ovarianos murinos, bovinos, caprinos e ovinos levando-se em consideração as substâncias presentes nos meios de cultivo utilizados e as prováveis vias de sinalização celular empregadas é apresentada na presente revisão.(AU)

Folliculogenesis is regulated by a complex process, which involves several intra- and extraovarian factors. The response of the ovarian cells to those factors depends on the signal transduction inside the cells through several signaling pathways. The interaction of different signaling pathways and discovery of new pathways demonstrate the complexity of folliculogenesis. Therefore, this review will highlight the main regulatory factors that control folliculogenesis, their receptors and sharing signaling pathways. Moreover, a critical analysis about the main results from in vitro follicle culture studies in murine, bovine, caprine, and ovine, focusing on the medium supplements and the interactions of their signaling pathways will be presented. (AU)

Avanços na criopreservação de tecido ovariano de cabras e ovelhas / Advances in ovarian tissue cryopreservation in goats and sheep

A criopreservação de tecido ovariano, sem dúvidas, tem se tornado, uma prática não apenas suplementar as técnicas de reprodução assistida, mas também fundamental para a preservação da fertilidade da fêmea. Isso tem sido observado, especialmente na espécie humana, cuja espécie em uma década de trabalho, já se soma aproximadamente trinta nascimentos de bebês saudáveis oriundos de ovário criopreservado. No entanto, todo o avanço que hoje é estabelecido, muito se deve aos trabalhos pioneiros realizados em animais de animais de produção como os ovinos. Relatos de sucesso após criopreservação e transplante de tecido ovariano no início dos anos 90 impulsionaram importantes equipes a investir esforços e dedicação nessa área, voltados para a reprodução humana, e embora, o sucesso seja evidente, os avanços da criopreservação de tecido ovariano tanto na espécie ovina, como na espécie caprina são ainda bastante limitados. Portanto, o objetivo desse trabalho, é apresentar uma retrospectiva dos principais resultados obtidos com a criopreservação de tecido ovariano nessas duas espécies.(AU)

Cryopreservation of ovarian tissue, no doubt, has been considerated not only as an additional practice to assisted reproductive techniques, but it is fundamental for female fertility preservation. This have been related particularly in humans, whose specie in a decade, it was reported approximately thirty healthy babies born after procedures of cryopreservation and tranplant of ovarian tissue. However, the currently successful is due to hard efforts done in animals farm such as sheep. Reports of success after cryopreservation and transplantation of ovarian tissue in the early 90 stimulated several researchers to invest efforts and dedication in that research field, regarding human reproduction, and although success is evident, advances in cryopreservation of ovarian tissue in sheep and goats are still quite limited. Therefore, the aim of this work is to present a retrospective of the main results obtained with the cryopreservation of ovarian tissue in these two species.(AU)

Avanços na criopreservação de tecido ovariano de cabras e ovelhas / Advances in ovarian tissue cryopreservation in goats and sheep

A criopreservação de tecido ovariano, sem dúvidas, tem se tornado, uma prática não apenas suplementar as técnicas de reprodução assistida, mas também fundamental para a preservação da fertilidade da fêmea. Isso tem sido observado, especialmente na espécie humana, cuja espécie em uma década de trabalho, já se soma aproximadamente trinta nascimentos de bebês saudáveis oriundos de ovário criopreservado. No entanto, todo o avanço que hoje é estabelecido, muito se deve aos trabalhos pioneiros realizados em animais de animais de produção como os ovinos. Relatos de sucesso após criopreservação e transplante de tecido ovariano no início dos anos 90 impulsionaram importantes equipes a investir esforços e dedicação nessa área, voltados para a reprodução humana, e embora, o sucesso seja evidente, os avanços da criopreservação de tecido ovariano tanto na espécie ovina, como na espécie caprina são ainda bastante limitados. Portanto, o objetivo desse trabalho, é apresentar uma retrospectiva dos principais resultados obtidos com a criopreservação de tecido ovariano nessas duas espécies.

Cryopreservation of ovarian tissue, no doubt, has been considerated not only as an additional practice to assisted reproductive techniques, but it is fundamental for female fertility preservation. This have been related particularly in humans, whose specie in a decade, it was reported approximately thirty healthy babies born after procedures of cryopreservation and tranplant of ovarian tissue. However, the currently successful is due to hardefforts done in animals farm such as sheep. Reports of success after cryopreservation and transplantation of ovarian tissue in the early 90 stimulated several researchers to invest efforts and dedication in that research field, regarding human reproduction, and although success is evident, advances in cryopreservation of ovarian tissue in sheep and goats are still quite limited. Therefore, the aim of this work is to present a retrospective of the main results obtained with the cryopreservation of ovarian tissue in these two species.

Proteínas de choque térmico Hsp70: estrutura e atuação em resposta ao estresse celular / Heat shock protein Hsp70: structure and action in response to cellular stress

Todas as células possuem mecanismos específicos para defender-se das agressões e condições estressantes imposta pelo ambiente. As proteínas de choque térmico (Hsp), além de auxiliar na síntese e dobramento de diversas outras proteínas em condições normais, representam um dos mecanismos mais conservados ativado em respostas a diversos tipos de estresse. Neste contexto, esta revisão aborda aspectos relacionados à descoberta e estrutura das proteínas Hsp, com destaque para a atuação da família Hsp70 na resposta celular ao estresse, interação com as vias apoptóticas, bem como a influência da criopreservação sobre a expressão destas proteínas.

All cells have specific mechanisms to defend itself from aggression and stressful conditions imposed by the environment. The heat shock proteins (Hsp), besides aiding in the synthesis and folding of several other normally represent one of the most conserved mechanisms activated in response to various types of stress. In this context, this review discusses aspects related to the discovery and structure of Hsp proteins, high lighting the role of Hsp70 in the cellular response to stress, interaction with apoptotic pathways, as well as the influence of cryopreservation on the expression of these proteins.

Proteínas de choque térmico Hsp70: estrutura e atuação em resposta ao estresse celular / Heat shock protein Hsp70: structure and action in response to cellular stress

Todas as células possuem mecanismos específicos para defender-se das agressões e condições estressantes imposta pelo ambiente. As proteínas de choque térmico (Hsp), além de auxiliar na síntese e dobramento de diversas outras proteínas em condições normais, representam um dos mecanismos mais conservados ativado em respostas a diversos tipos de estresse. Neste contexto, esta revisão aborda aspectos relacionados à descoberta e estrutura das proteínas Hsp, com destaque para a atuação da família Hsp70 na resposta celular ao estresse, interação com as vias apoptóticas, bem como a influência da criopreservação sobre a expressão destas proteínas.(AU)

All cells have specific mechanisms to defend itself from aggression and stressful conditions imposed by the environment. The heat shock proteins (Hsp), besides aiding in the synthesis and folding of several other normally represent one of the most conserved mechanisms activated in response to various types of stress. In this context, this review discusses aspects related to the discovery and structure of Hsp proteins, high lighting the role of Hsp70 in the cellular response to stress, interaction with apoptotic pathways, as well as the influence of cryopreservation on the expression of these proteins.(AU)

Tissue thickness may influence the outcome of vitrification of goat ovarian cortex

Background: The main advantage of the cryopreservation of ovarian fragments is a thinner tissue, which facilitates the penetration of cryoprotective agents, but the size of tissue may not be a limiting factor in achieving a successful cryopreservation of the ovarian tissue. This information is highly significant considering that the cryopreservation of hemi-ovary or whole ovary may preserve the entire or major part of the contingent of primordial follicles of ovarian fragments. Therefore, the aim of this study was to evaluate the vitrification of different dimensions goat ovarian tissue on the follicular morphology, viability, diameter, and the stromal cell density. Materials, Methods & Results: The ovarian tissue was vitrified as fragment, hemi-ovary, or whole ovary, and after warming, the preantral follicles were examined by trypan blue dye exclusion test and histological analysis. Preantral follicles incubated with trypan blue were considered viable if the oocyte and granulosa cells remained unstained. Preantral follicles were classified as morphologically normal only when they contained intact oocyte and granulosa cells. The follicular diameter was measured considering the major and minor axes of each follicle; the average of these 2 measurements was used to determine the diameter of each follicle. Ovarian stroma cells density was evaluated by calculating the number of stromal cell in an area of 100 × 100 µm. There was no difference in the percentage of morphologically normal and viable follicles after vitrification compared to the control (fresh tissue), regardless of the dimension of the vitrified ovarian tissue (P > 0.05). In addition, there were no differences in the follicular diameter after ovarian tissue vitrification, independent of the dimension (P > 0.05). However, after vitrifi cation, a decrease in the ovarian stromal cells density was observed (P < 0.05). This reduction was more intense after the vitrification of the hemi-ovary and whole ovary, compared to the ovarian fragment vitrification (P < 0.05). Discussion: No differences were observed in the percentages of morphologically normal and viable follicles from fresh or vitrified ovarian tissue (fragment, hemi-ovary, and whole ovary). These results are in agreement with other reports which no showed morphological changes after cryopreservation of the whole ovary, and the ovarian fragments. With respect to follicular diameter, only the diameter of the preantral follicles in ovarian tissue vitrified as hemi-ovary was similar to that observed in the fresh control, in the present study. The results demonstrate that fragments and whole ovary vitrification had greater cell dehydration (exposure to VS) and/or less cell rehydration (VS removal), showing that minor adjustments are needed in the protocols of cryoprotectants addition or removal from the fragments and the whole ovary. However, this reduction in follicular diameter did not appear to have affected the follicular architecture or cellular viability, which were maintained in all dimensions of ovarian tissue undergoing vitrifi cation. A reduction in the stromal cell density was observed, especially in the hemi-ovary and whole ovary as compared to the ovarian fragment. Previous reports have shown that ovarian stromal cells are responsible for the production of essential substances for follicular development and these substances are fundamental for follicles development and these cells tend to be more sensitive to cryopreservation procedure than ovarian follicles. In conclusion, the maintenance of follicular morphology and viability demonstrated that vitrification of goat ovarian tissue under the conditions applied in this study can be performed in any dimension of ovarian tissue (fragment, hemi-ovary, and whole ovary).