Hiperplasia fibroepitelial mamária felina (HFMF): novas perspectivas de regulação endócrina / Feline mammary fibroepithelial hyperplasia (FMFH): new perspectives of endocrine control

O controle da mamogênese, que inicia na fase embrionária e continua ao longo das várias etapas reprodutivas da fêmea, ainda não foi totalmente elucidado. Pesquisas nessa área geralmente são conduzidas com espécies produtoras de leite para fins comerciais, mas podem auxiliar nas investigações sobre a patogenia da hiperplasia fibroepitelial mamária felina (HFMF). Caracterizada como um fenômeno de crescimento anabólico que ocorre somente em algumas gatas, com proliferação celular nas estruturas alveolares, tanto no epitélio luminal quanto no mioepitélio, a HFMF pode exacerbar ao ponto de romper a pele e expor o parênquima mamário. Do ponto de vista endócrino, observa-se o envolvimento da progesterona, tanto endógena quanto exógena, aliada a uma sinergia com Hormônio do Crescimento (GH) e Fator de crescimento semelhante a insulina-1 (IGF-1). Todavia, a interação com outros hormônios envolvidos na mamogênese ainda é um campo aberto à pesquisa. Objetiva-se com esta revisão discorrer sobre os hormônios e fatores de crescimento celular relacionados à mamogênese e ocorrência de HFMF.(AU)

The control of mamogenesis, which starts on embryonic phase and continues throughout many female reproductive phases, was not fully understood. Researches on this field are commonly performed with dairy species, but support investigations focused on Feline mammary fibroepithelial hyperplasia (FMFH) pathogenesis. Characterized as a phenomenon of anabolic growth that occurs in few female cats, with alveolar proliferation in both luminal and myoepithelial cells, the FMFH can exacerbated and expose mammary parenchyma due to skin disruption. Endocrinologically it is observed participation of endogenous and exogenous progesterone, associated to synergism with Growth hormone (GH) and Insulin like growth factor-1 (IGF-1). However, interaction with other hormones enrolled on mammogenesis remains an open field to research. The goal of this review is to discuss about hormones and cellular growth factors related to mammogenesis and FMFH occurrence.(AU)

Hiperplasia fibroepitelial mamária felina (HFMF): novas perspectivas de regulação endócrina / Feline mammary fibroepithelial hyperplasia (FMFH): new perspectives of endocrine control

O controle da mamogênese, que inicia na fase embrionária e continua ao longo das várias etapas reprodutivas da fêmea, ainda não foi totalmente elucidado. Pesquisas nessa área geralmente são conduzidas com espécies produtoras de leite para fins comerciais, mas podem auxiliar nas investigações sobre a patogenia da hiperplasia fibroepitelial mamária felina (HFMF). Caracterizada como um fenômeno de crescimento anabólico que ocorre somente em algumas gatas, com proliferação celular nas estruturas alveolares, tanto no epitélio luminal quanto no mioepitélio, a HFMF pode exacerbar ao ponto de romper a pele e expor o parênquima mamário. Do ponto de vista endócrino, observa-se o envolvimento da progesterona, tanto endógena quanto exógena, aliada a uma sinergia com Hormônio do Crescimento (GH) e Fator de crescimento semelhante a insulina-1 (IGF-1). Todavia, a interação com outros hormônios envolvidos na mamogênese ainda é um campo aberto à pesquisa. Objetiva-se com esta revisão discorrer sobre os hormônios e fatores de crescimento celular relacionados à mamogênese e ocorrência de HFMF.

The control of mamogenesis, which starts on embryonic phase and continues throughout many female reproductive phases, was not fully understood. Researches on this field are commonly performed with dairy species, but support investigations focused on Feline mammary fibroepithelial hyperplasia (FMFH) pathogenesis. Characterized as a phenomenon of anabolic growth that occurs in few female cats, with alveolar proliferation in both luminal and myoepithelial cells, the FMFH can exacerbated and expose mammary parenchyma due to skin disruption. Endocrinologically it is observed participation of endogenous and exogenous progesterone, associated to synergism with Growth hormone (GH) and Insulin like growth factor-1 (IGF-1). However, interaction with other hormones enrolled on mammogenesis remains an open field to research. The goal of this review is to discuss about hormones and cellular growth factors related to mammogenesis and FMFH occurrence.

Role of the Na+/K+-ATPase ion pump in male reproduction and embryo development.

Na+/K+-ATPase was one of the first ion pumps studied because of its importance in maintaining osmotic and ionic balances between intracellular and extracellular environments, through the exchange of three Na+ ions out and two K+ ions into a cell. This enzyme, which comprises two main subunits (α and ß), with or without an auxiliary polypeptide (γ), can have specific biochemical properties depending on the expression of associated isoforms (α1ß1 and/or α2ß1) in the cell. In addition to the importance of Na+/K+-ATPase in ensuring the function of many tissues (e.g. brain, heart and kidney), in the reproductive tract this protein is essential for embryo development because of its roles in blastocoel formation and embryo hatching. In the context of male reproduction, the discovery of a very specific subunit (α4), apparently restricted to male germ cells, only expressed after puberty and able to influence sperm function (e.g. motility and capacitation), opened a remarkable field for further investigations regarding sperm biology. Therefore, the present review focuses on the importance of Na+/K+-ATPase on male reproduction and embryo development.

Influence of catalase and pre-freezing equilibration on post-thaw semen quality and conception rate in ewes laparoscopically inseminated

The aim of this study was to investigate the effects of catalase and pre-freezing equilibration during ram sperm cryopreservation on motility and membrane and acrosomal integrity of frozen-thawed semen, as well as conception rate following laparoscopic timedinsemination. Semen was collected from four mature Dorper rams, pooled and diluted in Tris egg-yolk extender basic solution (CON), or this solution supplemented with catalase (CAT; 20 U/100 × 106 sperm). Extended semen was packaged in 0.25 ml mini straws (25 × 106 sperm/straw), chilled (to 5°C), and then either frozen immediately (CON and CAT) or maintained at 5°C for 12 h of pre-freezing equilibration (CON12 and CAT12). Immediately after thawing and at 1 h after incubation at 37°C, kinematic parameters (CASA), plasma membrane integrity (PI-FITC), and acrosomal status (FITC-PNA) of sperm were assessed. There were no significant differences among the four groups on sperm traits evaluated immediately postthaw. However, after 1 h of incubation, total motility (46.7 and 25.0%) and plasma membrane integrity (38.7 and 25.7%) were higher (P < 0.05) in CAT12 than CON. When these two treatments were used for laparoscopic timed artificial insemination of ewes (with synchronized ovulation), conception rate was similar for CAT12 and CON (32.8%, n = 61 vs. 27.3%, n = 55). In conclusion, the combination of catalase and pre-freezing equilibration resulted in significantly improved quality of post-thawed ram semen without affecting conception rate in fixed-time laparoscopically intrauterine inseminated ewes.(AU)

Influence of catalase and pre-freezing equilibration on post-thaw semen quality and conception rate in ewes laparoscopically inseminated

The aim of this study was to investigate the effects of catalase and pre-freezing equilibration during ram sperm cryopreservation on motility and membrane and acrosomal integrity of frozen-thawed semen, as well as conception rate following laparoscopic timedinsemination. Semen was collected from four mature Dorper rams, pooled and diluted in Tris egg-yolk extender basic solution (CON), or this solution supplemented with catalase (CAT; 20 U/100 × 106 sperm). Extended semen was packaged in 0.25 ml mini straws (25 × 106 sperm/straw), chilled (to 5°C), and then either frozen immediately (CON and CAT) or maintained at 5°C for 12 h of pre-freezing equilibration (CON12 and CAT12). Immediately after thawing and at 1 h after incubation at 37°C, kinematic parameters (CASA), plasma membrane integrity (PI-FITC), and acrosomal status (FITC-PNA) of sperm were assessed. There were no significant differences among the four groups on sperm traits evaluated immediately postthaw. However, after 1 h of incubation, total motility (46.7 and 25.0%) and plasma membrane integrity (38.7 and 25.7%) were higher (P < 0.05) in CAT12 than CON. When these two treatments were used for laparoscopic timed artificial insemination of ewes (with synchronized ovulation), conception rate was similar for CAT12 and CON (32.8%, n = 61 vs. 27.3%, n = 55). In conclusion, the combination of catalase and pre-freezing equilibration resulted in significantly improved quality of post-thawed ram semen without affecting conception rate in fixed-time laparoscopically intrauterine inseminated ewes.

Canine testicular disorders and their influence on sperm morphology

The objective of this study was to evaluate the influence of testicular disease on sperm morphology. The reproductive tracts of 33 dogs were evaluated clinically and with ultrasound, followed by orchiectomy and harvesting of fluid from the vas deferens to evaluate sperm morphology. A section from each testis was used to conduct histological analyses. Histological changes were noted in 71.2% of testes (47/66). Regardless of dog age, the most frequent pathology was testicular degeneration (80.8%; 38/47), whereas testicular tumors were observed only in adult and old dogs (25.9%; 7/27). Harvesting fluid from the vas deferens for sperm morphology assessment was effective in 87.9% of cases (58/66), and severe testicular degenerative processes induced an increase (P < 0.05) in the percentage of abnormal sperm when compared with normal testes or those with moderate testicular degeneration (special attention given to detached heads). In conclusion, regardless of dog age, breed or origin, a severe testicular degeneration process led to a significant increase in detached heads. Furthermore, the collection of sperm from the vas deferens proved to be an alternative and reliable technique for future research.(AU)

Canine testicular disorders and their influence on sperm morphology

The objective of this study was to evaluate the influence of testicular disease on sperm morphology. The reproductive tracts of 33 dogs were evaluated clinically and with ultrasound, followed by orchiectomy and harvesting of fluid from the vas deferens to evaluate sperm morphology. A section from each testis was used to conduct histological analyses. Histological changes were noted in 71.2% of testes (47/66). Regardless of dog age, the most frequent pathology was testicular degeneration (80.8%; 38/47), whereas testicular tumors were observed only in adult and old dogs (25.9%; 7/27). Harvesting fluid from the vas deferens for sperm morphology assessment was effective in 87.9% of cases (58/66), and severe testicular degenerative processes induced an increase (P < 0.05) in the percentage of abnormal sperm when compared with normal testes or those with moderate testicular degeneration (special attention given to detached heads). In conclusion, regardless of dog age, breed or origin, a severe testicular degeneration process led to a significant increase in detached heads. Furthermore, the collection of sperm from the vas deferens proved to be an alternative and reliable technique for future research.