• Journal of electromagnetic engineering and science
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• 제15권3호
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• pp.142-150
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• 2015

Several reports supported that continuous exposure to 60 Hz magnetic field (MF) induces testicular germ cell apoptosis in vivo. We recently evaluated duration- and dose-dependent effects of continuous exposure to a 60 Hz MF on the testes in mice. BALB/c male mice were exposed to a 60 Hz MF at $100{\mu}T$ for 24 hours a day for 2, 4, 6, or 8 weeks, and at 2, 20 or $200{\mu}T$ for 24 hours a day for 8 weeks. To induce the apoptosis of testicular germ cell in mice, the minimum dose is $20{\mu}T$ at continuous exposure to a 60 Hz MF for 8 weeks, and the minimum duration is 6 weeks at continuous exposure of $100{\mu}T$. Continuous exposure to a 60 Hz MF might affect duration- and dose-dependent biological processes including apoptotic cell death and spermatogenesis in the male reproductive system of mice. The safety guideline of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) indicates that the permissible maximum magnetic flux density for general public exposure is $200{\mu}T$ at 60 Hz EMF (ICNIRP Guidelines, 2010). In the present study, we aimed to examine the expression of pro- and anti-apoptotic genes regulated by the continuous exposure to 60 Hz at $200{\mu}T$ in Sprague-Dawley rats for 20 weeks. The continuous exposure to 60 Hz at $200{\mu}T$ does not affect the body and testicular weight in rats. However, exposure to 60 Hz MF significantly affects testicular germ cell apoptosis and sperm count. Further, the apoptosis-related gene was scrutinized after exposure to 60 Hz at $200{\mu}T$ for 20 weeks. We found that the message level of endonuclease G (EndoG) was greatly increased following the exposure to 60 Hz at $200{\mu}T$ compared with sham control. These data suggested that 60 Hz magnetic field induced testicular germ cell apoptosis through mitochondrial protein Endo G.

• Advances in nano research
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• 제9권1호
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• pp.15-24
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• 2020

Iron has a crucial role in growth as part of metalo-proteins like haemoglobin or myoglobin, enzymes; they are also involved in energetic reactions. Iron plays a vital role in fertility. At high doses, Iron has a harmful consequence on the reproductive system, which can be strongly reflected the final stage of spermatogenesis. Nutritional products are claiming to use nanotechnology and it is important to recognize the potential toxicity of nano-sized nutrients. Recently iron nanoparticles were proposed as a food additive for poultry. The objective of this study was to investigate the effects of L-cystein coated iron oxide nanoparticles on reproductive performance in male quails. The results of Fourier Transform Infrared Spectrometer, Alternating Gradient Force Magnetometer and Scaning Electron Microscopy showed that iron oxide nanoparticles was produced and have been coated with L-cycstein (Fe₃O₄-Cys NPs). A total of 100 one-week-old quail chicks were randomly placed to five groups of five replicates. Four quails (two male and two females) were raised in an individual cage for each replicate. The five experimental treatment diets consisted; negative control diet, with no Iron supplementation; positive control diet supplemented with 60 mg/kg of Fe₃O₄; treatment diets supplemented with 0.6, 6 and 60 mg/kg of L-cystein coated iron oxide nanoparticles. The hemoglobin, Red blood cell, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, gonadal somatic index, daily sperm production, total testicular sperm and sperm viability of the male quails that were fed with diet supplemented by 0.6 mg/kg of Fe₃O₄-Cys NPs were improved as compare with negative control. This study showed that not only the use of the Fe₃O₄-Cys nanoparticles had no side effects but also it can be used as a feed additive to improve the reproductive performance in male quails.

• 한국수정란이식학회지
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• 제22권2호
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• pp.81-87
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• 2007

본 연구에서는 수컷 랫드에 DEHP를 투여하여 실험적으로 생식 독성을 유발하고, vitamin E와 catechin을 단독 및 병용 투여하여 수컷 랫드에서 정소의 조직학적 변화, 정액 특성의 변화 및 정자의 운동성 변화 등을 조사하여 그 예방 효과를 알아보고자 하였다. DEHP를 투여한 군은 대조군에 비해 정자농도, 정자 생존율, 정상 정자율이 감소하였다. DEHP에 의한 생식 독성을 예방하기 위해 vitamin E와 catechin을 단독 또는 병행 투여한 결과, DEHP를 투여한 군에 비하여 정자 농도, 정자 생존율, 정상 정자율이 증가하였다. 이러한 결과를 종합해 볼 때, catechin과 vitamin E의 투여는 DEHP에 의한 생식 독성을 예방하는 효과가 있는 것으로 사료된다.

• Advances in Traditional Medicine
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• 제9권1호
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• pp.49-57
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• 2009

The antifertility activity of methanol extract of Cuscuta reflexa Roxb. stem (MECR) and Corchorus olitorius Linn. seed (MECO) were studied on male Swiss albino mice. The extracts were found to decrease sperm count, percentage of motile sperm and testosterone level in treated mice when compared with vehicle control after 17 days of treatment. The weight of gonads, epididymis were decreased whereas no significant changes of the body weight of mice were observed after methanol extract treatments. The fertility test showed 100% negative result in MECR and MECO treated mice at medium and high dose level of treatment. MECR and MECO in low (25 mg/kg and 15 mg/kg, respectively), medium (50 mg/kg and 20 mg/kg, respectively) and high (75 mg/kg and 25 mg/kg, respectively) dose level caused a simultaneous fall in testicular ${\Delta}5$-$3{\beta}$-hydroxy steroid dehydrogenase and glucose-6-phosphate dehydrogenase activities which are involved in testicular steroidogenesis. Total cholesterol and ascorbic acid content in testis were increased significantly in gonads. The activities of lactate dehydrogenase, malic dehydrogenase and ascorbic acid oxidase were reduced whereas that of carbonic anhydrase was increased significantly in the testis of MECR and MECO treated mice. All these observations indicate that the methanol extract of C. reflexa stem and C. olitorius seed produced antifertility activity in sexually matured male mice, which may be due to inhibition of gonadal steroidogenesis. This activity may be attributed due to the presence of flavonoids and steroids, respectively.

• Clinical and Experimental Reproductive Medicine
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• 제35권4호
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• pp.293-301
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• 2008

목 적: 비폐쇄성 무정자증 환자에서 고환의 조직병리학적 진단에 따라 고환조직내 정자채취술 (Testicular sperm extraction, TESE) 후 난자세포질내 정자주입술 (Intracytoplsmic sperm injection, ICSI)의 체외수정시술 결과를 알아보고자 하였다. 연구방법: 비폐쇄성 무정자증으로 고환조직내 정자채취술 후 난자세포질내 정자주입술을 이용하여 배아 이식을 시행한 122주기를 분석하였다. 고환의 조직병리학적 진단에 따라 Germ-cell aplasia (GA, 40주기), Maturation arrest (MA, 32주기) and severe hypospermatogenesis (S-HS, 50주기)로 구분하여 체외수정시술 결과를 비교하였으며, 이들 결과를 난자세포질내 정자주입술을 이용한 폐쇄성 무정자증 환자의 체외수정시술 결과와 비교하였다. 결 과: 고환조직내 정자채취술 후 난자세포질내 정자주입술시 수정율은 각각 58.1% in GA, 42.2% in MA and 48.0% in S-HS로 조직병리학적 진단에 따른 차이는 없었으며, 폐쇄성 무정자증 환자의 72.9%에 비해 유의하게 낮은 수정율을 보였다 (p<0.001). 고환조직내 정자채취술시 채취된 정자 (spermatozoa, 94주기)로 난자세포질내 정자주입술을 시행한 주기의 배아 이식 후 임신율은 각각 22.6% in GA, 29.4% in MA와 26.1% in S-HS이었으며, 출생률은 각각 16.1%, 29.4%와 19.6%로 조직병리학적 진단에 따른 차이는 없었다. 정자세포 (spermatid, 16주기)를 사용하여 난자세포질내 정자주입술을 시행한 주기의 임신율은 각각 0.0% (0/3 주기), 9.1% (1/11주기)와 0.0% (0/2주기)이었으며, 출생률은 각각 0.0%이었다. 정모세포 (spermatocyte, 12주기)를 사용한 주기의 임신율은 각각 0.0% (0/6주기), 0.0% (0/4주기)와 0.0% (0/2주기)이었으며, 출생률도 각각 0.0%이었다. 결 론: 비폐쇄성 무정자증환자의 배아이식을 시행한 주기에서 고환의 조직병리학적 진단에 따른 난자세포질내 정자주입술시 수정율은 차이가 없었으며, 폐쇄성 무정자증 환자에 비해 유의하게 낮은 수정율을 보였다. 비폐쇄성 무정자증환자에서 고환조직내 정자채취술시 정자를 채취하여 난자세포질내 정자주입술을 시행한 주기의 체외수정시술 결과는 고환의 조직병리학적 진단에 따라 차이를 보이지 않는다.

• 대한수의학회지
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• 제49권4호
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• pp.279-284
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• 2009

This research aimed to investigate the time-course effect of epichlorohydrin (ECH) on epididymal histopathology in Sprague-Dawley rats. Twenty-four male rats were randomly assigned to four groups with 6 rats in each group and were administered a single oral dose of ECH (70 mg/kg) or its vehicle. Six animals each were sacrificed on days 0 (control), 1, 2, and 7 after treatment. During the study period, clinical signs, body weights, reproductive organ weights, testicular spermatid count, epididymal sperm count, motility and morphology, and histopathology were examined. No treatmentrelated effects on body weights and reproductive organ weights were noted at any time point. On the contrary, sperm motility decreased slightly on days 1 and 2 after treatment and then decreased significantly on day 7 after treatment. The first signs of histological changes were the appearance of cell debris in the ducts and vacuolization of the epithelial cells observed in the proximal caput epididymis on day 1 after treatment. The incidences and grades of the histological changes including cell debris in the ducts, epithelial vacuolization, oligospermia, and epithelial disruption increased on day 2 and then decreased slightly on day 7 after treatment. These results show that a single oral dose of 70 mg/kg ECH to male rats results in cell debris in the ducts and vacuolization of the epithelial cells in the proximal caput epididymis, followed by reversible oligospermia, epithelial disruption, and decreased sperm motility.

• 한국수정란이식학회지
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• 제30권3호
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• pp.213-218
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• 2015

In the study for a differentiation and development of spermatogonial cells, the researchers should commonly require a simple, fast and reasonable method that could evaluate the developmental stage of male germ cells without any damage and also relentlessly culture them so far as a cell stage aiming at experimental applications. For developing the efficient method to identify the stage of sperm cells, the morphological characteristics of sperm cells were investigated by staining the cells with blue fluorescent dye Hoechst 33258, and a criterion for male germ cell classification was elicited from results of the previous investigation, then the efficiency of the criterion was verified by applying it to assort the germ cells recovered from male mice in age from 6 to 35 days. As morphological characteristics, spermatogonia significantly differed from spermatocytes in size, appearance and fluorescent patches of nucleus, and spermatids could also be distinguished from spermatozoa by making a difference in the volume and shape of nucleus and the shape and fluorescence of tail. Aforesaid criterion was applicable for classifying in vitro cultured sperm cells by verifying its efficiency and propriety for assorting the stages of testicular germ cells. However, the fluorescent staining showed that germ cells in mouse testis should be dramatically differentiated and developed at 21 days and 35 days of age, which were known as times of sexual puberty and maturity in male mice, respectively. In conclusion, the results indicated that this simple criterion for sperm cell classification using fluorescence staining with Hoechst 33258 may be highly efficient and reasonable for spermatogenesis study.

• Animal cells and systems
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• 제1권1호
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• pp.99-105
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• 1997

Using three species of Korean frogs (Rana dybowskii, R. rugosa and R. nigromaculata), the annual spermatogenic pattern, the seasonal changes in the steroidogenic competence, and responsiveness of testis to gonadotropins in terms of testosterone secretion in vitro were examined. The spermatogenic pattern of R. dybowskii was classified as a discontinuous type since spermatogenesis stops completely after spawning in late winter (February) until mid-summer (July). In contrast, the pattern of R. nigromaculata and R. rugosa was classified as a potent continuous type since sperm was always present in the seminiferous tubules all year round. In all three species, the levels of testicular testosterone and that of testosterone secreted by testis following in vitro culture were very low in late summer (August), but increased thereafter until winter (hibernation period). Interestingly, responsiveness of testis in vitro to gonadotropins in terms of testosterone secretion increased markedly in November (early hibernation period). Specifically, bullfrog LH was more effective than FSH in stimulating the secretion of testosterone by frog testis in vitro during hibernation period. This fact suggests that testosterone secretion by testis during hibernation is at least regulated by the pituitary gonadotropin rather than environmental factors. Taken together, the data presented here suggest that testicular cycles of three species of Korean frogs are closely linked to their females breeding cycles, and are eventually controlled by various environmental cues.

• Applied Microscopy
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• 제39권3호
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• pp.245-252
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• 2009

모래무지아과에 속하는 한국고유종 돌마자 (Microphysogobio yaluensis)의 정소 내 생식세포를 조사하여 수온변화, 환경오염 및 서식지 파괴 등으로 멸종위기에 처한 한국고유종 보존을 위한 기초자료를 제시하고자 돌마자의 정소 내 생식세포의 특성을 확인한 바 다음과 같은 결과를 얻었다. 돌마자의 정소가 성숙초기에는 정소의 정소낭 내에는 발생과정이 비슷한 생식세포들이 분포하였으며, 정소낭과 정소낭 사이에는 라이디히 세포들이 존재하였다. 또한 성숙후기 정소의 정소낭에는 정자들이 가득하였으며 제2정모세포들도 남아있었다. 제1정모세포의 핵은 직경 3 ${\mu}m$ 정도의 구형이었으며 미토콘드리아들은 세포질 한 쪽에 모여 있었다. 제2정모세포들은 직경 1.5 ${\mu}m$ 정도의 구형 또는 난형의 핵을 보유하였으며 제1정모세포보다 작았다. 정자완성과정 중에 있는 정세포의 핵은 구형으로 전자밀도가 높게 나타났으며 편모를 형성하기 시작하였고 세포질의 미토콘드리아는 편모를 따라 재배열되었다. 특히 정자의 두부는 구형으로 첨체는 보유하지 않았으며 편모는 전형적인 9+2 구조의 미세소관으로 이루어져 있는 특성들을 나타내었다.

• Applied Microscopy
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• 제40권3호
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• pp.169-176
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• 2010

난태생어류인 성숙한 블랙몰리(black molly, Poecilia sphenops)와 세일핀몰리(sailfin molly, Poecilia latipinna)의 정소를 적출하여 정자형성과정과 정자의 미세구조를 광학현미경과 전자현미경을 이용하여 관찰하였다. 정소는 부레와 창자사이에 위치하고 있었고 장축 7 mm, 단축 2 mm 정도의 크기로 흰색을 띠고 있었다. 두 종 모두 정자형성 과정은 정소낭(testicular cyst)에서 이루어졌으며, 각 정소낭 내에 동일한 분화시기의 생식세포가 분포하고 있었다. 제1정모세포는 타원형으로 관찰되었으며, 핵과 세포질의 전자밀도는 다른 생식 세포들에 비해서 매우 낮았고 미토콘드리아는 핵막주위에 분포하고 있었다. 제2감수분열 전기의 태사기에 나타나는 태기사복합체(synaptonemal complex)들이 확인되는 경우도 있었다. 두 종 모두 제2정모세포는 구형으로 정원세포보다 크기는 작았고 인은 발달되어 있지 않았으며, 핵의 전자밀도는 더 높아졌다. 특히 미토콘드리아는 세포질 전체에 분포하고 있었고 정세포가 정자로 발달하는 정자완성과정시기에 편모가 형성되는 경우가 일반적이지만 이미 제2정모 세포시기에 편모형성이 관찰되었다. 정자의 중편부위를 횡단한 결과 미토콘드리아는 2~4개 정도로 관찰되었고 편모의 미세소관 배열은 전형적인 두 종 모두 9+2 구조를 이루고 있었고 편모에 lateral fin이 발견되었다. 성숙한 정자의 두부형태는 구형인 정세포와 달리 장원추형이었으며 염색질 응축이 매우 뚜렷하였고, 두부에서 첨체는 관찰되지 않았으며 중편부의 미토콘드리아는 두 종 모두 8~10개가 종렬로 위치하고 있었다. 이상과 같이 두 종의 정자형성과정과 정자의 형태는 같으며 이런 특징은 난태생 송사리과 어류의 공통적인 특성으로 생각된다.