Nucharin Songsasen - Academia.edu (original) (raw)

Papers by Nucharin Songsasen

Cancer Research, 2017

Reproductive failure following chemotherapy and/or ionizing radiation is a major adverse event, f... more Reproductive failure following chemotherapy and/or ionizing radiation is a major adverse event, for which there are no established preventive measures. In previous studies, our laboratory has documented that the selective estrogen receptor modulator, tamoxifen (TAM) is effective in both prevention and reversal of ovarian toxicity from cyclophosphamide (CTX) in rodent models. To validate the effectiveness of this approach in a more relevant model system, we have developed a canine ovarian explant tissue model system. Dogs present with many cancers spontaneously and their pathology and treatment approaches mirror those of the human cancers. Thus, canine cancers and their treatments are excellent translational models for human diseases. Furthermore, dogs share the same environment as humans and have longer life spans than rodents. Our laboratory has recently established a dog ovarian explant tissue model system using fresh ovaries collected at the time of ovariohysterectomy. In the cur...

Advances in experimental medicine and biology, 2014

Reproductive mechanisms are extraordinarily diverse among species, even within the same phylogene... more Reproductive mechanisms are extraordinarily diverse among species, even within the same phylogenetic clade. Due to this, it has been difficult to directly apply reproductive technologies developed in human and livestock to genetically manage ex situ wildlife, including carnivores. To date, more common, closely related species, e.g., domestic cats, dogs and ferrets have served as valuable models for developing reproductive technologies for managing rare, endangered carnivores. Artificial insemination and sperm cryopreservation have already been successfully used to manage ex situ populations in some carnivore species, such as the black-footed ferret, cheetah and giant panda. However, technologies aiming at preserving genetics of valuable females have not been fully developed in carnivores, due to the lack of fundamental knowledge about reproductive anatomy and physiology, gamete development, embryogenesis and cryopreservation. The present chapter is divided into two parts. The first ...

Animals

The reproductive physiology of canids is unique compared to other mammalian species. Specifically... more The reproductive physiology of canids is unique compared to other mammalian species. Specifically, the reproductive cycle of female canids is characterized by extended periods of proestrus and estrus followed by obligatory diestrus and protracted ovarian inactivity (anestrus). Although canid reproduction follows this general pattern, studies have shown variations in reproductive biology among species and geographic regions. Understanding of these differences is critical to the development of assisted reproductive technologies including estrus induction, gamete rescue, and embryo production techniques for canid conservation efforts. This review summarizes current knowledge of canid reproduction, including estrus cyclicity, seasonality, and seminal traits, with the emphasis on species diversity. The application of reproductive technologies in wild canid conservation will also be discussed.

PLOS ONE

The maned wolf (Chrysocyon brachyurus) is an induced ovulator. Though the mechanism of ovulation ... more The maned wolf (Chrysocyon brachyurus) is an induced ovulator. Though the mechanism of ovulation induction remains unknown, it is suspected to be urinary chemical signals excreted by males. This study assessed volatile organic compounds (VOCs) in weekly urine samples across 5 months from 13 maned wolves (6 intact males, 1 neutered male, 6 females) with the goal of identifying VOCs that are differentially expressed across sex, reproductive status, and pairing status. Solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) were used to extract and separate VOCs that were identified via spectral matching with authentic standards, with spectral libraries, or with new software that further matches molecular fragment structures with mass spectral peaks. Two VOCs were present across all 317 urine samples: 2,5-dimethyl pyrazine and 2-methyl-6-(1-propenyl)-pyrazine. Fifteen VOCs differed significantly (Adj. P < 0.001 and |log2 fold change| >2.0) between inta...

Aikens, Kate E. Jenks Ellen O., Songsasen, Nucharin, Calabrese, Justin, Fleming, Chris, Bhumpakph... more Aikens, Kate E. Jenks Ellen O., Songsasen, Nucharin, Calabrese, Justin, Fleming, Chris, Bhumpakphan, Naris, Wanghongsa, Sawai, Kanchanasaka, Budsabong, Songer, Melissa, Leimgruber, Peter (2015): Comparative movement analysis for a sympatric dhole and golden jackal in a human-dominated landscape. Raffles Bulletin of Zoology 63: 546-554

Fig. 3. Autocorrelation function (ACF) of: A, the dhole; and B, the jackal step length. Data poin... more Fig. 3. Autocorrelation function (ACF) of: A, the dhole; and B, the jackal step length. Data points above the dotted line are classified as autocorrelated.

Fig. 1. Dhole and jackal relocations overlaid on a land cover map of Khao Ang Rue Nai Wildlife Sa... more Fig. 1. Dhole and jackal relocations overlaid on a land cover map of Khao Ang Rue Nai Wildlife Sanctuary, Thailand.

Fig. 2. Decile-shaded isopleths of convex hull home ranges for the dhole and jackal in Khao Ang R... more Fig. 2. Decile-shaded isopleths of convex hull home ranges for the dhole and jackal in Khao Ang Rue Nai Wildlife Sanctuary, Thailand.

Lynam, Antony J., Jenks, Kate E., Tantipisanuh, Naruemon, Chutipong, Wanlop, Ngoprasert, Dusit, G... more Lynam, Antony J., Jenks, Kate E., Tantipisanuh, Naruemon, Chutipong, Wanlop, Ngoprasert, Dusit, Gale, George A., Steinmetz, Robert (2013): Terrestrial Activity Patterns Of Wild Cats From Camera-Trapping. Raffles Bulletin of Zoology 61 (1): 407-415

World Wildlife Fund for Nature-Thailand, Ladyao,

The global environment is under increasing pressure from expanding human activities and climate c... more The global environment is under increasing pressure from expanding human activities and climate changes. The change in global environment, including increase environmental temperature, marine pollution, ocean acidification among others, has resulted in significant loss in biodiversity. To dates, the International Union for Conservation of Nature (IUCN) has estimated that 41% of amphibians, 33% of corals, 26% of mammals and 13% of birds are threatened by extinction (International Union for Conservation of Nature IUCN, 2015). Imminent extinction of wild species is often caused by multiple factors and may not always be due to failure of animals to breed. Nevertheless, reproductive sciences play critical roles in wildlife conservation, especially captive breeding program. A clear example of how reproductive biology contributes to species recovery program is the case of black footed ferret (Howard et al., 2003; Santymire et al., 2014), endemic to North America. In 1980s, the species unde...

The culture of ovarian follicles is an important tool for understanding of the mechanisms control... more The culture of ovarian follicles is an important tool for understanding of the mechanisms controlling follicle development and differentiation of its oocyte. The benefit from recovering developmentally competent oocytes from small, immature follicles (primordial, primary, secondary and early antral) also would be significant, ranging from rescue of genomes from endangered species to preserving fertility in female cancer survivors. To-date, live offspring from cultured primordial follicles has occurred only in the mouse. Progress in larger, more complex species has been limited because these animal models have longer durations of natural folliculogenesis, thereby requiring more culture time to generate fully grown follicles and oocytes. In this presentation, we highlight current status of this topic for domestic carnivores (i.e., dogs and cats) as well as future research priorities.

Animals : an Open Access Journal from MDPI, 2021

Reproduction in canids has been characterized by having some peculiar aspects, such as the extend... more Reproduction in canids has been characterized by having some peculiar aspects, such as the extended reproductive cycle and ovulation of immature oocytes [...].

Reproduction and Fertility, 2021

Graphical Isolation of ovarian follicles is a key step in culture systems for large mammalian spe... more Graphical Isolation of ovarian follicles is a key step in culture systems for large mammalian species to promote the continued growth of follicles beyond the preantral stage in fertility preservation efforts. Still, mechanical isolation methods are user-skill dependent and time-consuming, whereas enzymatic strategies carry increased risk of damaging theca cell layers and the basement membranes. Here, we sought to determine an optimal method to rescue domestic cat (Felis catus) early antral and antral stage follicles from ovarian tissue and to evaluate the influence of isolation strategy on follicle development, survival, and gene expression during 14 days of in vitro culture in alginate hydrogel. Mechanical isolation was compared with 90 min digestion in 0.7 and 1.4 Wünsch units/mL Liberase blendzyme (0.7L and 1.4L, respectively). Mechanical isolation resulted in improved follicle growth and survival, and better antral cavity and theca cell maintenance in vitro, compared with 1.4L (...

Reproduction and Fertility, 2020

The red wolf is a critically endangered canid, with ~250 and ~20 individuals in the ex situ and r... more The red wolf is a critically endangered canid, with ~250 and ~20 individuals in the ex situ and reintroduced wild populations, respectively. Assisted reproductive technologies such as sperm cryopreservation and in vitro fertilization therefore represent critically-needed tools to manage these populations. However, the motility of post-thaw red wolf sperm rapidly declines during in vitro incubation, hindering the ability to develop these technologies. In this study, we evaluated the influence of several culture media (a modified canine capacitation medium (mCCM), a modified North Carolina State University-23 medium (mNCSU-23), a synthetic oviductal fluid (SOF), a fertilization Tyrode’s medium base or Fert-TALP (FERT), and a TRIS-based buffer (TRIS)) on the survival and capacitation of red wolf sperm during extended (18 h) incubation at 38.5°C and 5% CO2. Red wolf sperm motility averaged (±s.e.m.) 73.8 ± 7.1% at the time of collection, and was better maintained over 4 h incubation in ...

Reproductive Technologies in Animals, 2020

Abstract The ongoing decline in biodiversity loss can be mitigated with proper long-term genetic ... more Abstract The ongoing decline in biodiversity loss can be mitigated with proper long-term genetic and demographic management of threatened species under human care. However, natural breeding is not always successful and other supportive strategies must be considered, such as assisted reproductive technologies. Despite significant advancements in domesticated species, similar progress with wildlife species has been elusive, mostly due to the diverse reproductive biology of species within the same family. Aside from the more routine technologies, such as artificial insemination and in vitro fertilization, emerging technologies that rely on somatic and stem cells must be considered as potential options for the future. Continued progress will depend on the establishment of collaborative teams that can bring together the necessary animals, expertise, equipment, and funds to develop consistent and reproducible protocols.

Reproduction in Domestic Animals, 2020

Dog reproductive cycle is unique among other mammals in that females experience long and variable... more Dog reproductive cycle is unique among other mammals in that females experience long and variable periods of ovarian inactivity. Neuroendocrine controls of the reproductive cycle have been thoroughly studied in the dog. However, there is little information regarding endocrine, paracrine and autocrine controls of dog ovarian folliculogenesis. Advancements in the understanding of mechanisms regulating dog ovarian follicle development will be helpful in the development of an approach to control cyclicity in this species. Furthermore, such information will likely be useful for the establishment of an in vitro follicle culture system to preserve fertility of genetically valuable disease models or endangered canids. This review highlights current knowledge on dog folliculogenesis with emphasis on endocrine, paracrine and autocrine controls of follicular development.

International Journal of Molecular Sciences, 2020

Artificial insemination (AI) is a valuable tool for ex situ wildlife conservation, allowing the r... more Artificial insemination (AI) is a valuable tool for ex situ wildlife conservation, allowing the re-infusion and dissemination of genetic material, even after death of the donor. However, the application of AI to species conservation is still limited, due mainly to the poor survival of cryopreserved sperm. Recent work demonstrated that oviductal extracellular vesicles (oEVs) improved cat sperm motility and reduced premature acrosomal exocytosis. Here, we build on these findings by describing the protein content of dog and cat oEVs and investigating whether the incubation of cryopreserved red wolf and cheetah sperm with oEVs during thawing improves sperm function. Both red wolf and cheetah sperm thawed with dog and cat oEVs, respectively, had more intact acrosomes than the non-EV controls. Moreover, red wolf sperm thawed in the presence of dog oEVs better maintained sperm motility over time (>15%) though such an improvement was not observed in cheetah sperm. Our work demonstrates t...

Scientific Reports, 2020

Extracellular vesicles (EVs) contain multiple factors that regulate cell and tissue function. How... more Extracellular vesicles (EVs) contain multiple factors that regulate cell and tissue function. However, understanding of their influence on gametes, including communication with the oocyte, remains limited. In the present study, we characterized the proteome of domestic cat (Felis catus) follicular fluid EVs (ffEV). To determine the influence of follicular fluid EVs on gamete cryosurvival and the ability to undergo in vitro maturation, cat oocytes were vitrified using the Cryotop method in the presence or absence of ffEV. Vitrified oocytes were thawed with or without ffEVs, assessed for survival, in vitro cultured for 26 hours and then evaluated for viability and meiotic status. Cat ffEVs had an average size of 129.3 ± 61.7 nm (mean ± SD) and characteristic doughnut shaped circular vesicles in transmission electron microscopy. Proteomic analyses of the ffEVs identified a total of 674 protein groups out of 1,974 proteins, which were classified as being involved in regulation of oxidat...