Masculinization in juvenile longtooth grouper, Epinephelus bruneus, with aromatase inhibitor: changes in GtH subunit mRNA expression and steroids hormone levels

허성표,임봉수,황인준,김세재,유용운,허상우,송영보,정형복,백혜자,Akihiro Takemura,이영돈 한국통합생물학회 2012 Animal cells and systems Vol.16 No.2

We investigated the effects of fadrozol, an aromatase inhibitor (AI), and 17a-methyltestosterone (MT) on the induction of sex change in juvenile longtooth grouper Epinephelus bruneus, via histological observation of gonads. Changes in the mRNA expression of GtH subunits (FSH-b and LH-b) in the pituitary, and estradiol-17b (E2) and 11-ketotestosterone (11-KT) levels in the blood were also surveyed after AI and MT treatment. Juvenile longtooth groupers (113917 g body weight; 16.291.2 cm body length) received intramuscular injections of AI at 3 (3-AI) and 5 (5-AI) mg/kg BWdoses and MT at a 5 mg/kg BW (5-MT) dose. At week 7 post-injection, 3-AI and 5-MT oocytes were degenerated, and gonads of the 5-AI group initiated spermatogenesis. At week 21 post-injection, 3-AI- and 5-MT-treated gonads contained spermatogonia and spermatocytes, while 5-AI treatment induced advanced stages of spermatogenesis. The serum E2 level showed no significant differences throughout the experimental period, whereas that of 11-KT was significantly elevated in the 5-AI group at weeks 7 and 21 post-injection. A significant increase in the expression of FSH-b mRNA was evident in the 5-AI group at week 21 post-injection. In contrast, LH-b mRNA expression did not significantly differ among groups during the experimental period. These results imply that sex change has two stages in the longtooth grouper. In the first stage, oocytes are degenerated by the stimulation by 11-KT, and in the second stage spermatogenesis occurs, owing to the co-effects of 11-KT and FSH-b.

도두동 연안에 서식하는 어류의 종 조성 및 난 · 자치어 분포

이치훈,허성표,김성훈,이영돈 제주대학교 해양과환경연구소 2014 해양과환경연구소 연구논문집 Vol.38 No.-

To study the species composition of fish and distribution of ichthyoplanktons the coastal waters of Dodu-dong, Jeju was investigated for a total of four times underwater at spring (May) and autumn (November) 2008. Fish specimens were collected with a small net by SCUBA diving and fish specimens difficult to collect were photographed underwater using a underwater camera and a camcorder. A total of 43 species, 19 families, 3 orders were collected, and the dominant fish species were Chromis notata and Halichoeres tenuispinnis. The collected fish eggs and larvae were identified as belonging 4 species. The most dominant species Engraulis japonicus and Parabelnnius yatabei. The number of fish species was higher in autumn (November) than in spring (May), whereas the numbers of fish eggs were higher in spring (May). During the survey period, there were observed subtropical fish such as Chaetodontoplus septentrionalis, Microcanthus strigatus, Pomacentrus coelestis, Choerodon azurio, Labroides dimidiatus, Pseudolabrus eoethinus, Stethojulis interrupta terina, Siganus fuscescens and Ostracion immaculatus. The impacts of climate change, such as increasing water temperature have the potential to change geographical fish distribution. Further studies are need to consistently monitoring on the appearance of new subtropical fish correlated with climate change.

뱀장어 Anguilla japonica의 해수순치 후 기관세포의 조직 변화

이승현,허상우,이치훈,허성표,이영돈 제주대학교 해양과환경연구소 2014 해양과환경연구소 연구논문집 Vol.38 No.-

In teleosts fish, a number of species perform spectacular migrations between seawater and freshwater environmental conditions. Japanese eel, Anguilla japonica is a commercially important species and catadromous fish that grows in fresh water, and moves to the sea to spawn. This study investigated the histological changes of organs of A. japonica based on acclimated to the aquatic environment of the seawater. To understand histological changes of organs tissue of A. japonica based on fresh water condition and seawater condition, 6 specimens (mean TL 62±2 cm, mean BW 578±43 g) were used for comparative observation using gills and skin. A large amount of mucous cells were found and chloride cells were rarely observed in the gills in fresh water condition. However, mucous cells were not observed and chloride cells were increased in seawater condition. In the skin, mucous cells were observed in each layer of epidermis from fresh water condition. On the other hand, mucous cells of seawater condition were decreased in each layer of epidermis. In the future, additional comparative studies on environmental characteristics related to the aspect of artificial sex maturation by hormone treatment, another organ tissue changes and osmotic pressure will be necessary.

Relevance of Light Spectra to Growth of the Rearing Tiger Puffer Takifugu rubripes

김병훈,허성표,허상우,이치훈,이영돈 한국발생생물학회 2016 발생과 생식 Vol.20 No.1

In fish, light (photoperiod, intensity and spectra) is main regulator in many physiological actions including growth. We investigate the effect of light spectra on the somatic growth and growth-related gene expression in the rearing tiger puffer. Fish was reared under different light spectra (blue, green and red) for 8 weeks. Fish body weight and total length were promoted when reared under green light condition than red light condition. Expression of somatostatins (ss1 and ss2) in brain were showed higher expression under red light condition than green light condition. The ss3 mRNA was observed only higher expression in blue light condition. Expression of growth hormone (gh) in pituitary was detected no different levels between experimental groups. However, the fish of green light condition group was showed more high weight gain and feed efficiency than other light condition groups. Our present results suggest that somatic growth of tiger puffer is induced under green light condition because of inhibiting ss mRNA expression in brain by effect of green wavelength.

Tide-related Changes in mRNA Abundance of Aromatases and Estrogen Receptors in the Ovary and Brain of the Threespot Wrasse Halichoeres trimaculatus

오대주,허성표,Selma Bouchekioua,Yuki Takeuchi,Shingo Udagawa,Neelakanteswar Aluru,박용주,박지권,김세재,Thomas W. Moon,Mathilakath M. Vijayan,Akihiro Takemura 한국해양과학기술원 2018 Ocean science journal Vol.53 No.2

The threespot wrasse (Halichoeres trimaculatus; Family Labridae) is a common coral reef species of the Indo-Pacific Ocean. Given that this species spawns daily at high tide (HT), we hypothesized that endocrine changes in relation to gonadal development are synchronized with the tidal cycle. To test this, we examined the transcript abundance of two cytochrome P450 aromatases (cyp19a and cyp19b) and two estrogen receptors (erα and erβ) in the ovary and brain of this species in response to tidal change. When fish were collected around four tidal points [low tide (LT), flood tide (FT), high tide (HT), and ebb tide (ET)], gonadosomatic index and oocyte diameter increased around HT and FT, respectively. Ovulatory follicles were observed in ovaries around HT. Real-time quantitative polymerase-chain reaction revealed that mRNA abundance of cyp19a and erα, but not erβ, in the ovary increased around ET and HT, respectively. On the other hand, mRNA levels of cyp19b in the forebrain were significantly higher around FT. Increases of erα and erβ mRNA abundance around FT were observed in all areas of the brain and the midbrain, respectively. The changes in mRNA abundance of key genes involved in reproduction at specific tidal cycles, along with the development of the vitellogenic oocytes in the ovary, support our hypothesis that synchronization of endocrine changes to the tidal periodicity plays a role in the gonadal development of this species. We hypothesize that conversion of testosterone to E2 in the brain may be associated with the spawning behavior given that the wrasse exhibits group spawning with a territory-holding male around HT.

Exploring Rearing Water Temperature Conditions for Inducing Body Growth without Water Temperature Stress in Red-Spotted Grouper (Epinephelus akaara)

김병훈,허성표,최송희,이영돈,이치훈 한국해양과학기술원 2023 Ocean science journal Vol.58 No.4

This study explored appropriate rearing water temperatures that can minimize water temperature stress and induce body growth in the farmed red-spotted grouper (Epinephelus akaara). An examination of annual growth performance showed that body growth (body weight and total length) was induced faster from July to September 2020 than during other periods. Weight gain (WG), specific growth rate (SGR), and feed efficiency (FF) were highest in August 2020. The hepatocyte diameter increased significantly in June and October 2020. It was observed that the body weight and total length were significantly induced under the conditions of 26 °C and 32 °C. WG and SGR were highest at 26 °C and 32 °C, respectively, and FCR was highest at 26 °C. The expression of Cu/Zn-Superoxide dismutase (SOD) and Mn-SOD mRNA in the brain was significantly higher in the 32 °C group than that in the 26 °C group after 12 weeks. Expression of catalase (CAT) mRNA was significantly higher in the natural group than in the 26 °C group. The expression of Cu/Zn-SOD and CAT mRNA in the liver was significantly higher at a natural temperature at 8 weeks. The expression of Mn-SOD mRNA was significantly higher in the natural temperature group than that in the 32 °C group. The hepatosomatic index values and hepatocyte diameter tended to decrease more significantly at 26 °C and 32 °C. Our findings are based on growth performance and physiological indicators, and it is considered that a water temperature of 26 °C is suitable for farmed red-spotted groupers.

Ovarian Differentiation of the Scorpion Fish, Sebastiscus marmoratus

오성립,허성표,임봉수,이치훈,이영돈 한국발생생물학회 2006 발생과 생식 Vol.10 No.3

이 연구는 태생경골어인 쏨뱅이의 번식생태학적 기초자료를 제공하고자 체내 자어와 출산 후의 시원생식세포의 출현, 원시 생식소와 난소 분화과정을 조직학적으로 조사하였다. 약 의 시원생식 세포는 체내 자어의 초기 소화관과 중심신관 사이 복막에 위치하였다. 출산 후 31일째부터 생식원세포가 생식원기에 도달하였으며, 체세포들이 분열 증식하여 원시생식소를 형성하였고, 출산 후 49일째에 난소강이 형성되기 시작하였으며, 출산 후 60일째에 생식원기의 양쪽 끝에서부터 The process in the formation of primordial germ cells, primitive and early gonadogenesis were investigated by histological examination for the reproductive physiological study in the scorpion fish, Sebastiscus marmoratus. The primordial germ cells about in diameter were observed in the fibrous mesenchymal tissue located between gut and mesonephric duct of the larvae within the maternal body. As the fibrous epithelium extends to the direction of peritoneum, the primordial germ cells moved. From 31 days post parturition, the fibrous epithelium gets thicker, and the primitive gonad starts to form. From 49 days post parturition, as the primitive gonad of the primitive gonad extend, it starts to form cavity, and about 60 days post parturition, the formation of the ovarian cavity is completed. From 79 days post parturition, germ cells proliferated along the inner edge of the ovarian cavity.

Effects of Different Light Spectra on the Oocyte Maturation in Grass Puffer Takifugu niphobles

최송희,김병훈,허성표,이치훈,이영돈 한국발생생물학회 2018 발생과 생식 Vol.22 No.2

In order to examine the effects of four different light spectra (white, red, green, and blue) on the oocyte maturation, the change of reproductive parameters, via brain-pituitary-gonad (BPG) axis in grass puffer, were investigated. After exposure four different light spectra for 7 weeks, the abundance of gonadotropin-releasing hormone (GnRH) mRNA which is a type of seabream (sbGnRH) and two different subunit of gonadotropin hormones mRNAs, follicle-stimulating hormone (fshβ) mRNA and luteinizing hormone (lhβ) mRNA, were analyzed in the brain and pituitary. Histological analysis showed that the mature oocyte ratio in the green spectrum was higher than other light spectra-exposed groups. Gonadosomatic index (GSI) and oocyte developmental stage were also investigated in the gonad based on histological observations. GSI value with the presence of yolk stage oocytes was significantly increased in the green spectrum-exposed group when compared to that of the other light-exposed groups (white, red, and blue) (p˂0.05). The abundances of sbGnRH mRNA and fshβ mRNA in the green spectrum-exposed group were also significant higher than those of the other light spectra-exposed groups (p˂0.05). These results indicate that the maturation of oocyte in grass puffer can be accelerated by exposure to the spectrum of green. To better understand the molecular mechanism for the maturation of oocyte in grass puffer, further study examining the relationship between oocyte development and its related genes is required.

Long Photoperiod Affects Gonadal Development in Olive Flounder Paralichthys olivaceus

김병훈,이치훈,허상우,허성표,김대환,서해립,Sung Yeon Kim,이영돈 한국발생생물학회 2013 발생과 생식 Vol.17 No.3

To effects of sex maturation in olive flounder by regulating long photoperiod, gonadal development and GTH mRNA expression in the pituitary were investigated. Photoperiod was treated natural photoperiod and long photoperiod (15L:9D) conditions from September 2011 to March 2012. The results showed that natural photoperiodic group showed a higher gonadosomatic index (GSI) than long photoperiodic group during the spawning season (March 2012). The histological analysis of ovarian tissue showed that natural photoperiod group of ovaries contained vitellogenic oocytes, but long photoperiod group of ovaries mainly contained perinucleolus staged oocyte and oil-drop staged oocytes. The FSH mRNA of olive flounder, under natural photoperiod group, showed a significantly higher expression but no significant difference under long photoperiod group. The LHβ mRNA showed a significantly higher expression only under natural photoperiod group. These results may suggest that long photoperiodic information regulates secretion of pituitary FSH and LH and maintain early growing stage of gonadal development in this species.

Sasa quelpaertensis leaf extract mitigates fatigue and regulates the transcriptome profile in mice

송하나,장미경,이주엽,고희철,허성표,김세재 한국유전학회 2019 Genes & Genomics Vol.41 No.3

Introduction It has been reported that various plant species may enhance the elimination of fatigue-related metabolites. However, relatively few studies have directly addressed the potential anti-fatigue effects. Objective The objective of this study was to investigate the anti-fatigue potential of a hot water extract of Sasa quelpaertensis Nakai leaf (SQH) in male ICR mice. Methods The animals were divided into three groups. The normal control (NC) group was administered saline without exercise every day for 7 days. The exercise control (EC) and exercise with SQH (ES) groups were administered saline and SQH (50 mg/kg of body weight), respectively, every day for 7 days and underwent swimming exercise. RNA sequencing technology was used to analyze the transcriptome profiles of muscle. Results Swimming times were prolonged in the ES group compared with the EC group. The ES group had higher blood glucose and lower blood lactate levels, and higher muscular glycogen and lower muscular lactate levels, compared with the EC group. The groups did not differ in histopathological parameters of the muscle and liver, but muscle cell sizes were smaller in the EC group than in the ES and NC groups. RNA sequencing analysis revealed that SQH administration regulated genes associated with energy-generating metabolic pathways in skeletal muscle. Conclusion These results suggest that SQH exerts anti-fatigue properties by balancing various biological systems and helping maintain the basic harmonious pattern of the body.