N-acetylcysteine improves morphologic and functional aspects of ovarian grafts in rats

PURPOSE: To evaluate morphological and functional aspects of the ovarian graft in transplanted rats treated with NAC. METHODS: Female Wistar rats, virgin, 3 to 4 months old, weighing 200-250 grams were used in experiments. The rats have been kept in proper sanitary conditions, receiving food and water ad libitum. Five groups (n=10, each) were constituted: 4 groups treated subcutaneously with NAC, at doses of 150, 300, 600 and 1200 mg/kg (NAC150, NAC300, NAC600 and NAC1200, respectively), one hour of before the ovarian transplantation and control group (GTx) - treated with physiological solution and submitted to ovarian transplantation. The rats were anesthetized and submitted to autologous left ovarian transplantation, without anastomosis in retroperitoneum, and contralateral oophorectomy. During follow-up of 4 or 15 days, the estrous cycle was evaluated by vaginal smears to determine cycle regularity. At the end of 4th or 15th days, rats were re-anesthetized and blood and graft were obtained to estradiol analysis and morphological assessment. Data were analysed by One Way Analysis of Variance (ANOVA) or ANOVA on ranks complemented by Student-Newman-Keuls test. RESULTS: At 4th day, viable follicles in the graft did not altered by NAC treatments. The NAC300 and NAC600 groups showed increasing in follicle atresia (p=0.012) compared to GTx and NAC1200 group. At 15th day, 50% of GTx, NAC150, and NAC300 rats showed regular oestrous cycle; 83% of NAC600 and 100% of NAC1200 rats returned to regular cycle. NAC1200 group showed increasing in primordial follicle compared to GTx, NAC150 or NAC300 (p=0.011). NAC did not interfere in estradiol levels after 4 or 15 days of transplantation. CONCLUSION: In autologous ovarian transplantation, high dose of NAC promotes graft viability with recovery of estrous cycle. .

Goat ovarian follicles express different levels of mRNA for inhibin-ßA subunit and activin-A stimulates secondary follicle growth in vitro / Folículos ovarianos caprinos expressam diferentes níveis de RNAm para subunidade ßA da inibina e ativina-A promove o crescimento de folículos secundários in vitro

This study investigated the levels of messenger ribonucleic acids (mRNA) for inhibin-ßA subunit in goat primordial, primary and secondary follicles, as well as in cumulus-oocyte complexes (COCs) and mural granulosa / theca cells of antral follicles. The effects of activin-A (100ng mL-1) and/or follicle stimulating hormone (FSH, 50ng mL-1) on growth and expression of mRNA for activin-A and FSH receptor (FSH-R) in secondary follicles cultured for six days were evaluated. The data showed that the expression of inhibin-ßA is lower in secondary follicles than in primary follicles and is higher in large antral follicles than in small antral follicles. After culture, activin-A and/or FSH promoted growth of secondary follicles, while FSH increased the levels of mRNA for inhibin-ßA, and activin-A increased the levels of FSH-R mRNA. In conclusion, mRNA for inhibin-ßA is expressed at different levels in pre-antral and antral follicles and activin-A acts as a stimulator of the FSH-R expression in goat follicles. On its turn, the expression of inhibin-ßA is stimulated by FSH, which together with activin-A promotes secondary follicle growth in-vitro.

Este estudo investigou os níveis de ácidos ribonucleicos (RNAm) para a subunidade ßA da inibina em folículos primordiais, primários e secundários caprinos, bem como em complexos cumulus-oócitos (CCOs) e células da granulosa mural/teca de folículos antrais. Além disso, avaliaram-se os efeitos da ativina-A (100ng mL-1) e/ou hormônio folículo estimulante (FSH, 50ng mL-1) sobre o crescimento e a expressão do RNAm para inibina-ßA e receptores de FSH (FSH-R) em folículos secundários cultivados por seis dias. Os dados mostraram que a expressão de inibina-ßA é menor em folículos secundários do que em folículos primários e é maior em grandes folículos antrais que nos pequenos folículos antrais. Após o cultivo, ativina-A e/ou FSH promoveram o crescimento de folículos secundários. Enquanto o FSH aumentou os níveis de RNAm para inibina-ßA, a ativina-A aumentou os níveis de RNAm para FSH-R. Em conclusão, a inibina-ßA é expressa em diferentes níveis em folículos pré-antrais e antrais e a ativina-A atua como um estimulador da expressão de FSH-R em folículos caprinos. Por sua vez, a expressão de inibina-ßA é estimulada pelo FSH, que, juntamente com ativina, promove o crescimento de folículos secundários in vitro.

Teste de toxicidade e criopreservação de folículos pré-antrais ovinos isolados utilizando Glicerol, Etilenoglicol, Dimetilsulfóxido e Propanodiol / Toxicity test and cryopreservation of sheep isolated preantral follicles using glycerol, ethylen glycol, dimethil sulfoxyde and propanediol

O objetivo deste estudo foi avaliar foliculos pré-antrais (FOPA) ovinos isolados após sua exposição e criopreservação utilizando glicerol (GLI), etilenoglicol (EG), propanodiol (PROH) ou dimetilsulfóxido (DMSO) a 1,5 e 3,0 M. Cada par ovariano de 5 ovelhas sem raça definida foi coletado em abatedouro local e submetido ao isolamento folicular. Da suspensão obtida, uma aliquota foi imediatamente destinada à análise da viabilidade folicular com o auxílio do corante vital azul de trypan. O restante da suspensão foi dividida em 16 aliquotas de 0,9 mL, suspensas (v/v) em MEM+ com EG, DMSO, GLI ou PROH a 1,5 ou 3,0 M, para teste de toxicidade e criopreservação. Após o término de cada tratamento, a viabilidade folicular foi analisada e os FOPA considerados viáveis se não corados ou não viáveis, quando corados. A análise dos dados mostrou que após o teste de toxicidade e criopreservação, em todos os crioprotetores e em ambas as concentrações, a percentagem de FOPA viáveis foi significativamente reduzida quando comparada ao controle. No teste de toxicidade, quando os crioprotetores foram comparados entre si nas mesmas concentrações, foram observadas percentagens signifIcativamente menores de FOPA viáveis no PROH 3,0 M (38,9%), apresentando-se, portanto, mais tóxico quando comparado aos demais crioprotetores. Após criopreservação, obteve-se percentagens significativamente maiores de foliculos pré-antrais viáveis quando o EG e o DMSO foram utilizados. Em conclusão, FOPA ovinos isolados podem ser criopreservados com sucesso utilizando-se D MSO e EG a 1,5 e 3,0 M.

The aim of this study was to evaluate isolated sheep preantral follicles (PF) after exposure and cryopreservation using glycerol (GLI), ethylene glycol (EG), propanediol (PROH) or dimethyl sulfoxide (DMSO) at 1.5 and 3.0 M. Each ovarian pair from 5 mixed breed adult sheeps was obtained at a local slaughterhouse and submited to follicular isolation. From the obtained suspension, one aliquot was immediately analysed with trypan blue. The remaining suspension was divided in 16 aliquots of 0.9 mL, suspended in (v /v) in MEM+with EG, DMSO, GLI or PROH at 1.5 or 3.0 M to the toxicity test and cryopreservation. After the end of each treatment, the follicular viability was analysed and the PF were classified as viable if not dyed or not viable if dyed with trypan blue. The analysis of the results showed that after the toxicity test and cryopreservation, using all cryoprotectants and at both concentrations, the percentage of viable PF was significandy reduced when compared to the control. At the toxicity test, when the cryoprotectants were compared at the same concentrations, the lowest percentage of viable preantral follicles was obtained when 3.0 M PRO H (38,9%) was used, being, more toxic when compared to the others cryoprotectants. After cryopreservation, significantly higher percentual of viable PF was observed when the EG and DMSO were used. In conclusion, sheep PF can be cryopreserved successfully using DMSO and EG at 1.5 and 3.0 M.