• Molecules and Cells
• /
• 제22권1호
• /
• pp.30-35
• /
• 2006

Munc18, a mammalian homolog of C. elegans Unc, is essential for neurotransmitter release. The aim of this study was to identify estrogen-dependent expression of Munc18-1 and its role in the regulation of glutamate release for puberty onset. Hypothalamic munc18-1 mRNA levels were significantly increased by estrogen treatment in ovariectomized, immature female rats. During pubertal development, the munc18-1 mRNA levels dramatically increased between the juvenile period and the anestrous phase of puberty. Intracerebroventricular administration of an antisense oligodeoxynucleotide against munc18-1 mRNA significantly decreased glutamate release and delayed the day of puberty onset. These results suggest that Munc18-1, expressed in an estrogen-dependent manner, plays an important role in the onset of female puberty via the regulation of glutamate release.

• 한국식품위생안전성학회지
• /
• 제21권4호
• /
• pp.197-203
• /
• 2006

Parabens are most wildly used in food, cosmetics and pharmaceutic products as preservatives caused of safety and cheap. we had examined that paraben had estrogenic activity through the in vivo and in vitro experiments in last year. We demonstrated that most of parabens(ethyl, butyl, propyl, isobutyl, isopropyl) increased significantly uterus weight as well as induced proliferation of MCF-7 cell and binding of estrogen receptor as endocrine disrupter compounds. In this study, we evaluated that whether parabens have effect on male reproductive system or not. the male rats were administrated parabens by oral injection then examined separation of preputial day for $PND23\simPND52$. As the results, most parabens delayed pubertal development compare to control group. The separation of preputial day of Butyl and Propyl parabens at high concentration were PND 44 days and PND 45days compared to control group as PND 40 days. Even though, parabens as endocrine disrupter wildly spread in food, cosmetics and pharmaceutic products, we didn't have the safe guideline. In abroad, they are re-evaluating safety assessment for parabens. In conclusion, parabens delayed pubertal development in juvenile parabens are consider as endocrine disrupter chemicals.

• 동아시아식생활학회지
• /
• 제23권5호
• /
• pp.519-532
• /
• 2013

The purpose of this study was to make a comparative analysis of dietary habits, snacks, eating out and fast-food intake between students with a relatively early sexual maturity and others with a relatively late sexual maturity in a bid to grasp the impact of dietary behaviors on sexual maturity. The subjects in this study were 565 boys and girls who resided in Seoul and Gyeonggi province. They included fifth- and sixth-grade school children and seventh-grade middle school students. To classify the selected students according to the level of sexual maturity, the students of the same month age were divided into two groups in consideration of the stage of their sexual maturity and that of the other age groups. The early mature group was significantly taller and weighed more than the late mature group irrespective of gender. According to Tanner stages, the boys of the early mature group reached a 3.03 stage of sexual maturity when the sexual organs were taken into account, and those of the late mature group reached a 1.50 stage of sexual maturity. The girls of the early mature group reached a 3.43 stage of sexual maturity on the basis of breast, and those of the late mature group reached a 2.73 stage of sexual maturity. Concerning eating out, the early mature group ate out more frequently than the late mature group. In regard to snacks, the early mature group had a snack more often. The findings of the study indicated that there were differences in physical development and some dietary behaviors according to sexual maturity. The early mature group had a snack and ate out relatively more often than the late mature group, which showed that some dietary behaviors had an impact on the sexual maturity of the teens who arrived at the age of puberty.

• Clinical and Experimental Pediatrics
• /
• 제55권8호
• /
• pp.265-271
• /
• 2012

Phytoestrogen is an estrogenic compound that occurs naturally in plants. The most common sources of phytoestrogen are soybean products, which contain high levels of isoflavones. This compound, which has structural similarity with estrogen, can act as an estrogen receptor agonist or antagonist. Animal studies provide evidence of the significant effects of phytoestrogen on sexual development, including altered pubertal timing, impaired estrous cycling and ovarian function, and altered hypothalamus and pituitary functions. Although human studies examining the effects of phytoestrogen on sexual development are extremely limited, the results of some studies agree with those of the animal studies. In this paper, we review the possible mechanism of phytoestrogen action and the evidence showing the effects of phytoestrogen on sexual development in animal and human studies.

• Journal of Animal Science and Technology
• /
• 제59권12호
• /
• pp.25.1-25.7
• /
• 2017

Background: Rabbit breeding with high performance imported ones would be of benefit for genetic diversity and improvement of performance in domestic rabbit breeds. The rearing of more productive rabbit breeds could be pathway to improve the productivity and reduce the production cost. Maternal nutritional status exert a great influence on reproductive functions of does, which may expand from conception, through gestation and parturition and development of kits to puberty. Methods: Four breeds of rabbit were evaluated for their parturition, weaning and pubertal differences among the rabbit population in Ibadan, Nigeria. The breed consist of Fauve De Bourgogne (FDB), Chinchilla (CHA), British Spot (BS) and New Zealand White (NZW) rabbits. A total of 60 bucks and 360 does consisting of 15 bucks and 90 does per breed were mated in 6 mating cycles, three each of natural mating and artificial insemination. All does were synchronized for estrus with 20 IU pregnant mare serum gonadotropin 48 h prior to mating. The does after parturition were assessed for milk yield (g) and kit survival rate (%) till weaning, weight changes of kits from birth to puberty. At puberty, the pubertal age (days) and weight (g) of the offspring were assessed. Result: Results obtained reveals that British Spot doe had highest milk yield among the breeds which significantly increased growth of kit and weight at weaning in British Spot rabbits. Survival rates of Chinchilla kits were significantly (p < 0.05) higher than Fauve de Bourgogne, British Spot and New Zealand White kits. Puberty attainment of the rabbits indicates that British spot does and Fauve de Bourgogne bucks are early maturing. Conclusion: Chinchilla shows high kit survivability and British spot has highest milk yield among the four breeds of rabbit.

• Asian-Australasian Journal of Animal Sciences
• /
• 제17권12호
• /
• pp.1647-1651
• /
• 2004

The follicles (1.8 to 7.8 mm in diameter) were recovered from the ovaries in marketed pigs and the number of granulosa cells, the diameter of oocytes obtained from different development stages of the follicles and follicular fluid levels were determined. Correlations between size measurements and cell counts as well as the diameter of antral follicles and oocytes were also investigated. The results indicated that, while expanding in size, follicle numbers decreased with a greater atretic proportion. Granulosa cells increased in numbers continuously and remained unchanged beyond the size of 200 ${mm}^3$ in non-atretic follicles, whereas a sudden drop of granulosa counts was observed in atretic follicles. Follicular fluid, on the other hand, linearly increased its volume with follicle size and differed little between those of non-atretic and atretic follicles. Diameters of oocytes in non-atretic follicles increased to its maximum when follicles expanded to 150 ${mm}^3$ and maintained its size during later follicular expansion. It is concluded that, for in vitro culture, the optimal size of porcine follicle should be between 150 to 180 ${mm}^3$if they are collected from pre-pubertal gilts of marketing size slaughtered in an abattoir.

• 한국발생생물학회지:발생과생식
• /
• 제10권4호
• /
• pp.215-225
• /
• 2006

사춘기 조숙증은 여아에서 8세 이전에 유방 발육이 있거나 남아에서 9세 이전에 고환이 4 mL 이상 커지는 것으로 정의되는데 최근 사춘기 발현 연령이 점차 낮아지고 있다. 사춘기를 시작하는 gonadotrophin releasing hormone(GnRH)의 활성화에는 흥분성 및 억제성 아미노산, 성장인자, 전사조절인자, 아디포카인 등 많은 인자들이 복합적으로 작용한다. 특발성 사춘기 조숙증의 원인으로서 유전인자, 영양상태(특히 체지방 증가), 환경호르몬 노출 등 여러 가지 원인이 추정되고 있다. 사춘기 조숙증은 정서적 스트레스뿐 아니라 성장판의 조기폐쇄로 인한 저신장을 초래할 수 있다. 사춘기 조숙증은 진성 성조숙증과 가성 성조숙증으로 분류할 수 있으며 gonadotrophin이 활성화되는 진성 성조숙증에서는 적절한 시기에 GnRH 길항제를 치료하였을 때 사춘기 지연 및 최종 성인 신장을 호전시키는 것으로 보고되고 있으나 그 효과 및 장기적 부작용에 대해서는 좀더 연구가 필요하리라 사료된다.

• Journal of Nutrition and Health
• /
• 제37권7호
• /
• pp.566-575
• /
• 2004

To compare the dietary intakes and body composition in the stage of puberty, this study was conducted with 360 girls aged 9 to 12 years in Seoul Korea. Girls's general information and 3-day diet records were collected, fat mass was measured by Inbody 3.0, bone mass at right calcaneus was measured by PIXI and pubertal development was self-assessed by picture of Tanner stages. The results are as follows: Girls who had breast development were 79.7% and 15.8% had pubic hair development. Mean of BMI, BMC and BMD were significantly higher at breast stage3+(19.6 kg/$m^2$, 1.62 kg, 0.47 g/$\textrm{cm}^2$) than at the breast stage2 (18.2 kg/$m^2$, 1.47 kg, 0.44 g/$\textrm{cm}^2$) or breast stage1(16.3 kg/$m^2$, 1.32 kg, 0.39 g/$\textrm{cm}^2$) (p < 0.001). Percent body fat of breast stage1, 2, and 3+ were 19.7%, 23.1%, 25.3% respectively and significantly increased during the puberty (p < 0.001). The mean of energy intake was 1629 kcal in stage1, 1664 kcal in stage2 and 1577 kcal in stage3+ showed significant difference in the breast stages (p < 0.05). Energy adjusted sodium intakes and crude fiber intakes were significantly higher in breast stage3 + than other breast stages. For zinc and iron, proportions of subjects with intake levels less than 75% of Korean RDA was over 40% and significantly higher in breast stage3+ than other stages (p < 0.05) ; for protein and vitamin E, the proportions of subjects with intake levels more than 125% RDA was significantly higher in the stage 1. The nutrient adequacy ratio (NAR) for protein and phosphorous was significantly lower in breast stage3+ than other stages. The food groups of seed and nut were 4.7 g/day, 2.3 g/day, 1.8 g/day, respectively, and was significantly higher in breast stage 1. In summary, mean of BMI, BMD, BMC and percent of body fat were increased with pubertal development, and those who had higher breast developmental stage showed a lower amount of consumption level in energy, seeds and nuts, and also showed a higher amount of consumption level in energy adjusted sodium and fiber among Korean girls.

• 한국식품위생안전성학회:학술대회논문집
• /
• 한국식품위생안전성학회 2001년도 The Asia-Pacific Conference on Reproductive Biology and Environmental Sciences
• /
• pp.54-60
• /
• 2001

• Clinical and Experimental Reproductive Medicine
• /
• 제50권4호
• /
• pp.213-222
• /
• 2023

Cryopreservation is an option for the preservation of pre- or post-pubertal female or male fertility. This technique not only is beneficial for human clinical applications, but also plays a crucial role in the breeding of livestock and endangered species. Unfortunately, frozen germ cells, including oocytes, sperm, embryos, and spermatogonial stem cells, are subject to cryoinjury. As a result, various cryoprotective agents and freezing techniques have been developed to mitigate this damage. Despite extensive research aimed at reducing apoptotic cell death during freezing, a low survival rate and impaired cell function are still observed after freeze-thawing. In recent decades, several cell death pathways other than apoptosis have been identified. However, the relationship between these pathways and cryoinjury is not yet fully understood, although necroptosis and autophagy appear to be linked to cryoinjury. Therefore, gaining a deeper understanding of the molecular mechanisms of cryoinjury could aid in the development of new strategies to enhance the effectiveness of the freezing of reproductive tissues. In this review, we focus on the pathways through which cryoinjury leads to cell death and propose novel approaches to enhance freezing efficacy based on signaling molecules.