Gamete Rescues from Gonads of Wild Animal Post-mortem

Transcription

1 Review Article Gamete Rescues from Gonads of Wild Animal Post-mortem Kaywalee Chatdarong Abstract Wild animals usually die unexpectedly. After post-mortem, there is a short time for gamete rescue because tissue degeneration occurs rapidly in the field area. It is crucial to develop rescue strategies to obtain good gamete quality for future offspring production. Applications of reproductive biotechnologies, e.g. gamete cryopreservation, in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), in vitro follicular culture and xenotransplantation, are necessary to propagate the value rescued genes to the endangered populations. Epididymis and testis are sources of male gametes while oocytes from antral- and preantral follicles are female gametes that have been reported to successfully produce offspring. This review contains summary of the current research interests that aim to rescue, preserve and apply valuable gametes from wild endangered animals after death. Keywords: endanger, gamete, rescue Department of Obstetrics, Gynaecology and Reproduction, Faculty of Veterinary Science, Chulalongkorn University. *Corresponding author kaywalee.c@chula.ac.th Thai J Vet Med Suppl :

2 100 Chatdarong K. / Thai J Vet Med Suppl : Introduction Many wild animals have been claimed as endangered due to their habitat loss during these decades. When these valuable endangered animals die, there is a narrow window of time for the last opportunity preserved gametes with the purpose of assuring optimal quality of gametes for propagating new offspring in the future. After animals die, the carcass decomposition occurs rapidly. Thus, it is important to develop gamete rescue protocols to secure their fertility potential. Understanding of gamete rescue and preservation is beneficial to efficient collection and utilization them. So far, epididymides and testis tissues are important sources of male gametes while oviducts and ovarian tissues are sources of female gametes. Epididymal sperm, similar to ejaculated sperm, have utility for artificial insemination (AI), in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). Testicular sperm have higher potential to retain viability after freezing and thawing compared to epididymal sperm, but their utilization is limited to ICSI. Alternatively, testis tissues containing spermatogonial stem cells utilize stem cell technology to propagate live offspring. In female, oocytes recovered from oviducts and antral follicles are capable of IVF after maturation in vitro whereas preantral follicles need in vitro culture or xenotransplantation for future usage. This review contains summary of the current research interests that aim to rescue, preserve and apply valuable gametes from wild endangered animals after death. Time lags prior to gamete retrieval There are two sessions of time prior to gametes retrieval that affect success of gamete preservation. The first is the duration from animal died to necropsy and the second is from gonad retrieval to gamete recovery in laboratories. At room temperature, the histopathological study found that chromatin in the Leydig cell, Sertoli cell, spermatogonia and spermatocytes degenerated after the rats died in 12 hours (Bryant and Boekelheide, 2007) whereas oocytes in the oviducts and follicles in the ovaries of the mice autolysed within 10 min and 30 min, respectively, after death (Miao et al., 2007). The data suggested that necropsy to excise gonads out of the carcass should be performed soon after animals died to avoid decomposition which is usually accelerated in the body. However, we obtained 81% testicular sperm viability from a Siamese Eld s deer at 10 hours after post-mortem (K. Chatdarong, unpublished data), implying that gametes preserved in the gonadal tissue are more resistant to autolysis than mature gametes in the tract. Because wild animal populations are usually far from laboratories, effects of temperature and duration during gonad transport are in focus. The cleavage rate has been shown to be higher when the Iberian red deer ovaries were stored at 5-8 o C than that stored at o C (Garcia-Alvarez et al., 2011). Our previous study using domestic cats as a model for wild felids demonstrated that maintaining sperm in the epididymides provided similar sperm quality as in the tris egg-yolk extender and the sperm quality was unchanged from the fresh sample within 24 hours (Chatdarong et al., 2009). Moreover, the cold storage of domestic and wild cat testicular sperm more than 24 hours compromised the viability although the DNA integrity was not changed (Thuwanut et al., 2011). In contrast, using dogs as a model for wild canids, the previous study showed the decrease in the motility when the epididymal sperm were stored in the epididymides compared to in the extender for 24 hours (Gleawketgarn et al., 2011). Preservation of male gamete Mature spermatozoa can be retrieved from ejaculates and epididymides whereas immature male gametes, i.e. testicular spermatozoa, spermatocyte, spermatid and spermatogonia, are extracted from testicular tissues. Sperm extender and freezing protocol for the mature spermatozoa are varied among animal species. There is no universal protocol developed for all. Our current researches demonstrated that glutathione peroxidase was capable of improving the flat-headed cat (Prionailurus planiceps) ejaculated sperm motility and mitochondrial membrane potential after frozen-thawed (Thuwanut et al., 2011) as well as the epididymal sperm of the domestic cats (Thuwanut et al., 2010). Whether the glutathione peroxidase would give the same result for epididymal sperm of the flat-headed cat is worth further investigation. For epididymal sperm preservation, a single-layer colloid centrifugation has been reported to be able to remove cellular contamination from the domestic cat epididymides and select morphologically normal sperm, sperm with intact membrane and DNA resulting in the better IVF environment (Chatdarong et al., 2010). This method might be beneficial also to improvement of sperm quality collected from the epipidymides of endangered species. Apart from mature spermatozoa, the immature testicular sperm cells are cryopreserved in forms of sperm suspension or as testicular tissue. Among testicular tissue freezing methods, two-steps freezing by lowering temperature of the tissue in a styrofoam box has been postulated as being superior to vitrification (P. Thuwanut and K. Chatdarong, unpublished data). Live births produced by ICSI using extracted spermatozoa from cryopreserved testicular tissues have been reported in rabbits (Shinohara et al., 2002) and human (Hovatta et al., 1996, Park et al., 2003). Preservation of female gamete Cryopreservation is required for female gamete because it is not always that spermatozoa of the same species will be available for IVF or ICSI at the same time as the females die. Cryopreservation can be performed on immature and mature oocytes, but mature oocytes seem to be more vulnerable to freezing because they have more complex structure, particularly the cytoskeleton and cortical granule. The recent study succeeded in vitrifying immature cat oocytes using stepwise cryoprotectant exposure resulting in successful pregnancy following embryo transfer (Tharasanit et al., 2011). However, the

3 Chatdarong K. / Thai J Vet Med Suppl : decomposition process after the animal die usually results in rapid degeneration of oocytes. Out of the total of 846 oocytes recovered from 13 nondomestic cat species, only 164 (32.3%) matured to metaphase II in vitro (Johnston et al., 1991). Ovaries of an adult cat contain 37,853 preantral follicles consisted of 87% primodial follicle, 10.4% primary follicle and 2.3% secondary follicle (Carrijo et al., 2009). Based on the fact that ovaries contain several thousands of preantral follicles, these female gametes are attractive to be saved as genetic pool. The oocytes in the follicles are commonly cryopreserved in form of ovarian tissues. Follicles are occupied in ovarian cortex. Although vitrification is easy and simple to perform in the fields, our study demonstrated that passive cooling resulted in the better results (Tanpradit and Chatdarong, 2011). Applications of cryopreserved testicular and ovarian tissue Using ICSI technology, testicular sperm of the cow (Keskintepe et al., 2002) and the cat (Moisan et al., 2005) have been reported to succeed in producing embryos. Spermatogonia are used to reproduce mature spermatozoa by spermatogonial stem cell transplantation (SSCT). After spermatogonial stem cells were injected back into seminiferous tubules or efferent ducts, spermatogenesis has been proven possible in many species (Honaramooz et al., 2002, Izadyar et al., 2003, Zhang et al., 2003). Moreover, xenogenic SSCT using mice as recipients is possible. However, testis xenografting has more advantageous over the others in that after success of the grafting, the Leydig cells remain their function on testosterone production. Successes have been reported only when neonatal or early juveniles are the donors, i.e. the pig (Honaramooz et al., 2002), the cows (Oatley et al., 2005) and the cats (Snedaker et al., 2004). Follicles extracted from ovarian tissues can be isolated and grown in vitro in a culture medium or grown in vivo using a xenotransplantation technique. Studies are focused on investigating hormones and factors influencing growth of the follicles in the culture medium. We had succeeded in in vitro growing of follicles derived from the Burmese Eld s deer postmortem (Thuwanut et al., 2011). Recently, a 3-dimensional system has been introduced with a success of producing metaphase II oocytes, blastocysts and live births in several species (Xu et al., 2006, Telfer et al., 2008). Moreover, ovarian tissue transplantation is found to be beneficial and successful (O Brien et al., 2003). Xenotransplantation can be performed by orthotopic grafting or heterotopic transplantation (Donnez et al., 2004). References Bryant, B.H. and Boekelheide, K Timedependent changes in post-mortem testis histopathology in the rat. Toxicol Pathol. 35: Carrijo, O.A., Marinho, A.P.S., Campos, A.A., Amorim, C.A., Bao, S.N., Lucci, C.M Morphometry, estimation and ultrastructure of ovarian preantral follicle population in queens. Cells Tissues Organs 191: Chatdarong, K., Thuwanut, P., Suksamai, P., Patanatiradaj, S., Sangwornrachasup, A Survival of frozen-thawed cat spermatozoa precooled in the epididymides. Reprod Dom Anim Suppl. 44(2): Chatdarong, K., Thuwanut, P., Morrell, J.M Single-layer centrifugation through colloid selects improved quality of epididymal cat sperm. Theriogenology 73: Donnez, J., Dolmans, M.M., Demylle, D.Jadoul, P., Pirard, C., Squifflet, J., Martinez-Madrid, B., van Langendonckt, A Live birth after orthotopic transplantation of cryopreserved ovarian tissue. Lancet 365: Garcia-Alvarez, O., Maroto-Morales, A., Berlinquer, F., Fernandez-Santos, M.R., Esteso, M.C., Mermillod, P., Ortiz, J.A., Ramon, M., Perez- Guzman, M.D., Garde, J.J., Soler, A.J Effect of storage temperature during transport of ovaries on in vitro embryo production in Iberian red deer (Cervus elaphus hispanicus). Theriogenology 75: Gleawketgarn, N., Hoonaukit, C., Taechangam, N. and Chatdarong K Comparison of frozenthawed epididymal dog sperm quality after cold stored in epididymis and in extender. In : Proc 1 st Symposium of the Thai Society for Animal Reproduction, Sept , Bangkok, Thailand. Honaramooz, A., Mege, S.O. and Dobrinski, I Germ cell transplantation in pigs. Biol Reprod. 66, Hovatta, O, Foudila, T., Siegberg, R., Johansson, K., von Smitten, K. and Reima, I Pregnancy resulting from intracytoplasmic injection of spermatozoa from a frozen-thawed testicular biopsy specimen. Hum Reprod. 11: Izadyar, F., den Ouden, K., Stout, T.A., Stout, J., Coret, J., Lankveld, D.P., Spoormakers, T.J., Colenbrander, B., Oldenbroek, J.K., van der Ploeg, K.D., Woelders, H., Kal, H.B. and De Rooij, D.G Autologous and homologous transplantation of bovine spermatogonial stem cells. Reproduction 126: Johnston, L.A., Donoghue, A.M., O Brien, S.J., Wildt, D.E Rescue and maturation in vitro of follicular oocytes collected from non-domestic felid species. Biol Reprod. 45: Keskintepe, L., Pacholczyk, G., Machnicka, A., Norris, K., Curuk, M.A., Khan, I. and Brackett, B.G Bovine blastocyst development from oocytes injected with freeze-dried spermatozoa. Biol Reprod. 67: Miao, D.Q, Ma S.F., Liu, X.Y., Sui, H.S., Zhang, X., Qiao, T.W. and Tan, J.H Effects of delayed excision of oviducts/ovaries on mouse oocytes and embryos. Mol Reprod Dev. 74: Moisan, A.E., Leibo, S.P., Lynn, J.W., Gomez, M.C., Pope, C.E., Dresser, B.L. and Godke, R.A

4 102 Chatdarong K. / Thai J Vet Med Suppl : Embryonic development of felid oocytes injected with freeze-dried or air-dried spermatozoa. In: Animal Meeting of the Society for Cryobiology, Minneapolis, MN, USA. p.33. Park, Y.S., Lee, S.H., Song, S.J., Jun, J.H., Koong, M.K. and Seo, J.T Influence of motility on the outcome of in vitro fertilization/intracytoplasmic sperm injection with fresh vs. frozen testicular sperm from men with obstructive azoospermia. Fertil Steril. 80: Shinohara, T., Inoue, K., Ogonuki, N., Kanatsu- Shinohara, M., Miki, H., Nakata, K., Kurome, M., Nagashima, H., Toyakuni, S., Kogishi, K., Honjo, T. and Ogura, A Birth of offspring following transplantation of cryopreserved immature testicular pieces and in-vitro microinsemination. Hum Reprod. 17: Snedaker, A.K., Honaramooz, A. and Dobrinski, I A game of cat and mouse: xenografting of testis tissue from domestic kittens results in complete cat spermatogenesis in a mouse host. J Androl. 25: Tanpradit, N. and Chatdarong, K Cat ovarian tissue cryopreservation using a passive cooling device. In: Proc 1 st Symposium of the Thai Society for Animal Reproduction, Sept , Bangkok, Thailand. Telfer, E.E., McLaughin, M., Ding, C. and Thong, K.I A two-step serum-free culture system supports development of human oocytes from primordial follicles in the presence of activin. Hum Reprod. 23: Tharasanit, T., Manee-In, S., Buarpung, S., Chatdarong, K., Lohachit, C. and Techakumphu, M Successful pregnancy following transfer of feline embryos derived from vitrified immature cat oocytes using stepwise cryoprotectant exposure technique. Theriogenology, doi: /j.theriogenology Thuwanut, P., Chatdarong, K., Johannisson, A., Bergqvist, A.S., Soderquist, L. and Axner, E Cryopreservation of epididymal cat spermatozoa: effects of in vitro antioxidative enzymes supplementation and lipid peroxidation induction. Theriogenology 73: Thuwanut, P., Chatdarong, K., Bergqvist, A.S. Soderquist, L., Thiangtum, K., Tongthainan, D. and Axner, E The effects of antioxidants on semen traits and in vitro fertilizing ability of sperm from the flat-headed cat (Prionailurus planiceps). Theriogenology 76: Thuwanut, P., Wongbandue, G. and Chatdarong, K Testicular felid sperm quality: Effects of testicular storage time and cryopreservation by two-step freezing method. In: Proc 8 th International Conference on Behaviour, Physiology and Genetics in Wildlife, Sept , Berlin, Germany.

5 103