Action of cholesterol-loaded cyclodextrin on viability of ram semen

Background: Studies report that cyclodextrins have the property of carrying cholesterol to the membrane, but in some casescan also remove this cholesterol from the plasma membrane. The mechanism of action of CLC is not well understood,however, it seems to involve sperm protection during the freezing and thawing process. Studies show that its use enhancingincreased osmotic tolerance and reduced premature sperm capacitation reaction. In this sense, studies report that cyclodextrins have the property of carrying cholesterol to the membrane, but in some cases can also remove this cholesterol fromthe plasma membrane. Improvements were reported in the sperm parameters of buffaloes, bulls, stallions and sheep. Ramnaturally present less lipids in their membrane, on average 27%, while bulls have 31%, rabbits 62%, and humans 50%.The aim of the present study was to evaluate the use of cholesterol-loaded cyclodextrin (CLC), a commercial diluent, inthe kinetics and viability of frozen and thawed ram spermatozoa.Materials, Methods & Results: Five ejaculates, from five rams of Dorper breed were collected and divided into three groups:control, 1 mg CLC and 2 mg CLC. Semen was diluted in different concentrations of CLC (0, 1, and 2 mg/120×106 spermatozoa), and incubated at room temperature (21°C) for 10 min. Samples were conditioned in 0.5 mL straws and incubatedat 5°C for 4 h, exposed to LN2 vapor for 10 min and storing a cryogenic container. The parameters as spermatic kinetics,plasma membrane, acrosomal membrane (MPAI, %), and intracellular levels of superoxide anion (O2-) were evaluated.Sperm progressive motility (PM), rapid spermatozoa percentage (RAP), linearity (LIN, %), average path velocity (VAP,μm/s) and MPAI (%) were more satisfactory with the use of 1 mg compared to 2 mg (P < 0.05). In addition, 1 mg CLCshowed decreased levels of superoxide anion formation (O2-), a free...

Action of cholesterol-loaded cyclodextrin on viability of ram semen

Background: Studies report that cyclodextrins have the property of carrying cholesterol to the membrane, but in some casescan also remove this cholesterol from the plasma membrane. The mechanism of action of CLC is not well understood,however, it seems to involve sperm protection during the freezing and thawing process. Studies show that its use enhancingincreased osmotic tolerance and reduced premature sperm capacitation reaction. In this sense, studies report that cyclodextrins have the property of carrying cholesterol to the membrane, but in some cases can also remove this cholesterol fromthe plasma membrane. Improvements were reported in the sperm parameters of buffaloes, bulls, stallions and sheep. Ramnaturally present less lipids in their membrane, on average 27%, while bulls have 31%, rabbits 62%, and humans 50%.The aim of the present study was to evaluate the use of cholesterol-loaded cyclodextrin (CLC), a commercial diluent, inthe kinetics and viability of frozen and thawed ram spermatozoa.Materials, Methods & Results: Five ejaculates, from five rams of Dorper breed were collected and divided into three groups:control, 1 mg CLC and 2 mg CLC. Semen was diluted in different concentrations of CLC (0, 1, and 2 mg/120×106 spermatozoa), and incubated at room temperature (21°C) for 10 min. Samples were conditioned in 0.5 mL straws and incubatedat 5°C for 4 h, exposed to LN2 vapor for 10 min and storing a cryogenic container. The parameters as spermatic kinetics,plasma membrane, acrosomal membrane (MPAI, %), and intracellular levels of superoxide anion (O2-) were evaluated.Sperm progressive motility (PM), rapid spermatozoa percentage (RAP), linearity (LIN, %), average path velocity (VAP,μm/s) and MPAI (%) were more satisfactory with the use of 1 mg compared to 2 mg (P < 0.05). In addition, 1 mg CLCshowed decreased levels of superoxide anion formation (O2-), a free...(AU)

Colesterol carregado pela ciclodextrina sobre a criopreservação dos espermatozoides de garanhões da raça Nordestina / Cholesterol-loaded cyclodextrin on the cryopreservation of stallion sperm of the Northeastern breed

Nesta pesquisa avaliou-se o efeito do colesterol sobre o sêmen de garanhões da raça Nordestina sobre a qualidade espermática. Vinte ejaculados de dois garanhões foram diluídos com BotuSemen e colesterol carreado pela ciclodextrina (CCC) adicionado no sêmen: controle, 0,75mg de CCC e 1,0mg de CCC/120x106 sptz/mL, e incubado a 26°C/15min. O sêmen foi diluído 1:5 (v/v) com diluente Lactose-gema de ovo e resfriado a 5°C/2h, envasado em palhetas de 0,5mL, e acondicionado sob vapor de nitrogênio líquido, e depois imersos. As amostras foram descongeladas (37 °C/30s) e avaliadas. As variáveis foram avaliadas com ANOVA e teste de Tukey (P<0,05). A motilidade total e progressiva foi maior (P<0,05) no sêmen tratado com CCC comparado as amostras do grupo controle, e CCC promoveu maior percentual (P<0,05) de motilidade total e progressiva durante as 3 horas de incubação. A percentagem de espermatozoides com viabilidade e integridade foi maior (P<0,05) no sêmen tratado com CCC (81,47 e 86,07%) comparado ao controle (72,12 e 70,19%). O número de espermatozoides reativos ao teste hiposmótico foi maior (P<0,05) nas amostras de sêmen tratadas com CCC comparado ao controle. Adição de colesterol no sêmen de garanhões Nordestino melhora a qualidade espermática apos a criopreservação.(AU)

In the study effect of cholesterol was evaluated on the sperm quality of Nordestina stallion breed. Twenty semen samples were used from two stallions, diluted with BotuSemen extender and cholesterol add as follows: control, 0.75mg of cholesterol-loaded cyclodextrin (CLC) and 1.0mg of CLC/120x106 sperm/mL, and incubated for 15 min at 22°C. The samples were diluted 1:5 with lactose-yolk egg extender and cooled to 5°C over two hours, loaded into 0.5mL straws and frozen in static liquid nitrogen vapor before being plunged into nitrogen. Samples were thawed (37°C/30s) and analyzed. The variables were analyzed by ANOVA and means compared by Tukey test (P<0.05). Higher percentages of total and progressive motile was higher for sperm treated with CLC compared to control, and CLC promoted higher percentages (P<0.05) of total and progressive motility for the 3 hours of incubation. The percentage of viability and plasma membrane integrity of spermatozoa were higher (P<0.05) in sperm treated with CLC compared to the control group. The number of spermatozoa reacted to hypoosmotic test was higher (P<0.05) in sperm treated with CLC than control. Addition of CLC in the semen of Nordestina stallion breed improve the sperm quality after cryopreservation.(AU)

Colesterol carregado pela ciclodextrina sobre a criopreservação dos espermatozoides de garanhões da raça Nordestina / Cholesterol-loaded cyclodextrin on the cryopreservation of stallion sperm of the Northeastern breed

Nesta pesquisa avaliou-se o efeito do colesterol sobre o sêmen de garanhões da raça Nordestina sobre a qualidade espermática. Vinte ejaculados de dois garanhões foram diluídos com BotuSemen e colesterol carreado pela ciclodextrina (CCC) adicionado no sêmen: controle, 0,75mg de CCC e 1,0mg de CCC/120x106 sptz/mL, e incubado a 26°C/15min. O sêmen foi diluído 1:5 (v/v) com diluente Lactose-gema de ovo e resfriado a 5°C/2h, envasado em palhetas de 0,5mL, e acondicionado sob vapor de nitrogênio líquido, e depois imersos. As amostras foram descongeladas (37 °C/30s) e avaliadas. As variáveis foram avaliadas com ANOVA e teste de Tukey (P<0,05). A motilidade total e progressiva foi maior (P<0,05) no sêmen tratado com CCC comparado as amostras do grupo controle, e CCC promoveu maior percentual (P<0,05) de motilidade total e progressiva durante as 3 horas de incubação. A percentagem de espermatozoides com viabilidade e integridade foi maior (P<0,05) no sêmen tratado com CCC (81,47 e 86,07%) comparado ao controle (72,12 e 70,19%). O número de espermatozoides reativos ao teste hiposmótico foi maior (P<0,05) nas amostras de sêmen tratadas com CCC comparado ao controle. Adição de colesterol no sêmen de garanhões Nordestino melhora a qualidade espermática apos a criopreservação.(AU)

In the study effect of cholesterol was evaluated on the sperm quality of Nordestina stallion breed. Twenty semen samples were used from two stallions, diluted with BotuSemen extender and cholesterol add as follows: control, 0.75mg of cholesterol-loaded cyclodextrin (CLC) and 1.0mg of CLC/120x106 sperm/mL, and incubated for 15 min at 22°C. The samples were diluted 1:5 with lactose-yolk egg extender and cooled to 5°C over two hours, loaded into 0.5mL straws and frozen in static liquid nitrogen vapor before being plunged into nitrogen. Samples were thawed (37°C/30s) and analyzed. The variables were analyzed by ANOVA and means compared by Tukey test (P<0.05). Higher percentages of total and progressive motile was higher for sperm treated with CLC compared to control, and CLC promoted higher percentages (P<0.05) of total and progressive motility for the 3 hours of incubation. The percentage of viability and plasma membrane integrity of spermatozoa were higher (P<0.05) in sperm treated with CLC compared to the control group. The number of spermatozoa reacted to hypoosmotic test was higher (P<0.05) in sperm treated with CLC than control. Addition of CLC in the semen of Nordestina stallion breed improve the sperm quality after cryopreservation.(AU)

Uso de colesterol na criopreservação espermática e fertilidade: uma revisão / Use of cholesterol in sperm cryopreservation and fertility: a review / Uso de colesterol en la criopreservación espermática y fertilidad: una revisión

A criopreservação é um método amplamente utilizado para o armazenamento de células espermáticas em longo prazo. Essa técnica facilita a difusão e a disponibilidade de material genético a ser utilizado tanto na produção in vitro (PIV) como na inseminação artificial, biotecnologia aplicada na maioria das espécies domésticas. Pesquisas têm desenvolvido estratégias para otimizar a utilização do sêmen por meio da redução das injúrias ocorridas durante o processo de criopreservação, e vem conseguindo melhorar os parâmetros espermáticos pós-descongelação com a adição de ciclodextrina carregada com colesterol (CCC) ao sêmen puro ou previamente diluído das diferentes espécies estudadas. Apesar dos resultados promissores, melhor fertilidade do sêmen tratado com CCC tem sido demonstrada somente in vitro, enquanto que in vivo os resultados ainda não são compensatórios, necessitando maiores investigações para tornar viável a aplicação comercial dessa técnica. O objetivo dessa revisão foi compilar alguns resultados dos principais pesquisadores na área, expondo o estado atual e as perspectivas para melhorias da fertilidade do sêmen tratado com CCC.(AU)

Cryopreservation is a method widely used for the long-term storage of sperm cells. This technique facilitates the dissemination and availability of genetic material to be used in both in vitro production (IVP) and in artificial insemination, the biotechnology applied to most domestic species. Research has developed strategies to optimize the use of semen through the reduction of injuries occurred during the cryopreservation process, having succeeded in improving post-thaw sperm parameters with the addition of cholesterol-loaded cyclodextrin (CLC) to pure or previously diluted semen samples from the different species studied. Despite the promising results, better fertility of semen treated with CLC has only been demonstrated in vitro, while in vivo results are not yet feasible, requiring further investigation to result in viable commercial application of such technique. The objective of this review is to compile a few results from the leading researchers in the area, exhibiting the current state and prospects for improving the fertility of semen treated with CLC.(AU)

La criopreservación es un método ampliamente utilizado para el almacenamiento de células espermáticas a largo plazo. Esa técnica facilita la difusión y la disponibilidad de material genético a ser utilizado tanto en la producción in vitro (PIV) como en la inseminación artificial, biotecnología aplicada en la mayoría de las especies domesticas. Investigaciones han desarrollado estrategias para perfeccionar la utilización del semen por medio de la reducción de las injurias ocurridas durante el proceso de criopreservación, y ha conseguido mejorar los parámetros espermáticos pos descongelamiento con la adición de ciclodextrina cargada con colesterol (CCC) al semen puro o previamente diluido. A pesar de los resultados promisores, mejor fertilidad del semen tratado con CCC ha sido demostrado solo in vitro, mientras que in vivo los resultados todavía no son compensatorios, necesitando de mayores investigaciones para volver viable la aplicación comercial de esa técnica. El objetivo de esa revisión ha sido compilar algunos resultados de los principales investigadores del área, exponiendo el estado actual y las perspectivas para mejorías de la fertilidad del semen tratado con CCC.(AU)