• 대한수의학회지
• /
• 제45권4호
• /
• pp.545-552
• /
• 2005

The major protocol features of the rodent uterotrophic assay have been evaluated using a range of reference chemicals. The protocol variables considered include the selection of the test species and route of chemical administration, the age of the test animals, the maintenance diet used, and the specificity of the assay for estrogens. The rodents were ovariectomized under general anesthesia via bilateral flank incisions and randomly assigned to groups of 5 animals. Chemicals were DEHP, DBP, BPA and NP, were injected sc once daily with combinations of chemicals treatments for 3 days. In the results, the reported estrogenic chemicals DEHP and DBP were both negative in the single dose treatments. But, in the combinations of chemicals treatments, DEHP and DBP increased in bud number of mammary gland. Treatment of ovariectomized mice with combinations of other chemicals resulted in uterine and vaginal hyperplasia. The additive estrogenic effects were seen with the combinations of $17{\beta}$-Bestradiol and DBP treatment. the competitive estrogenic effects were seen with the combinations of $17{\beta}$-Bestradiol and nonylphenol, $17{\beta}$-Bestradiol and bisphenol-A treatments. These results offers a sysmatic and mechanistically informative approach to assessing estrogenicity. it provides a useful profile of activity using a reasonable amount of resources and is compatible with the study of individual chemicals as well as the investigation of interactions among combinations of chemicals. The results described illustrate the intrinsic complexity of evaluating chemicals for estrogenic activities and conform the need for rigorous attention to experimental design and criteria for assessing estrogenic activity.

• 한국환경독성학회:학술대회논문집
• /
• 한국환경독성학회 2003년도 추계국제학술대회
• /
• pp.57-69
• /
• 2003

It is well known that many pesticides possess hormonal activity, and affect the developments of wildlife and mammals including human. Currently, pyrethroid insecticides are in worldwide use to control in and outdoor pests, providing potential far environmental exposure. Hormonal activities of these pyrethroid insecticides, however, have been little studied, and the developmental effects of them were no reported. Therefore, we firstly examined the potential estrogenic activities of some pyrethroid insecticides (permethrin, cypermethrin, tetramethrin, deltamethrin, sumithrin, fenvalerate and bioallethrin) by immature rat uterotrophic assay, luciferase reporter gene assay and Calbindin-D$\sub$9k/ (CaBP-9k) gene expression assay. Uterine wet weights were increased by permethrin and the permethrin-induced weights were inhibited by ICI 182780 in the uterolrophic assay. On the other hand tetramethrin significantly reduced uterine and vaginal wet weights, and also inhibited the E2-induced weight increases at all doses tested. Cypermethrin and sumithrin had a tendency to increase uterine weights, although not statistically significant. Permethrin and cypermethrin dose-dependently increased the luciferase activity in reporter gene assay. Northern blot analysis showed that permethrin induced CaBP-9k mRNA expression whereas tetramethrin inhibted. Subsequent studies were conducted to investigate the possible developmental effects of four pyrethroid insecricides (permethrin, cypermethrin, sumithrin and teramethrin). Either diethlbestrol (DES) or 17${\beta}$ -estradiol (E2) was used as a reference control in this study. Pyrethroid insecticides were administered to Sprague Dawley rats via subcutaneous injection at 6 to 18 days of gestation or 1 to 5 days after birth. In utero treatment of permethrin (10mg/kg/day) in female rat resulted in significant increases in uterine and ovarian weights while significant decreases in serum E2 concentration, uterine and ovarian ER${\alpha}$ mRNA levels. Sumithrin and permethrin led to acceleration in vaginal opening of female rat, while delay in preputial separation of male after neonatal treatment. Anogenital distances of PND 18 were significantly reduced in sumthrin-treated, and permerhrin-treated male rats after neonatal treatment. All the pyrethroid insecticides tested caused significant increases in uterine weights on PND 18, while significant reductions in the first diestrus phase when neonataly treated. In addition, exposure to pyrethroids in neonatal period led to significant reduction in relative brain weight in female rat on PND 18, but its weight was recovered in diestrus phase. In summary, Our experimental data demonstrate the possibilities of developmental effects of pyrethroid insecticides via estrogenic or antiestrogenic activity.

• 한국식품위생안전성학회지
• /
• 제21권2호
• /
• pp.118-128
• /
• 2006

본 시험은 암컷 랫드에 파라벤류(에틸, 프로필, 이소프로필, 부틸, 이소부틸)를 생후 19일령부터 21일령까지3일간 투여하여 자궁비대반응을 관찰하고, 이를 토대로 시험물질의 내분비계 장애작용을 검색하고자 실시하였다. 본 시험의 투여기간 동안 사망은 발생하지 않았으나, 용량결정시험에서 관찰된 것과 같이 투여부위의 피하결절 및 부종의 증상이 관찰되었으며, 이러한 증상들은 용량의존적으로 증가되는 경향을 나타내었고, 점차 투여부위의 탈모 및 가피형성 등의 과정을 거치면 발전되었다, 이러한 증상은 투여용량이 다소 낮은 음성대조군 및 양성대조군에서 발생하지 않아, 분말상태의 시험물질이 고용량으로 현탁되어 투여되며 생긴 물리적인 영향에 의한 것으로 사료되었으며, 시험물질의 에스트로겐성의 영향과는 무관한 것으로 사료되었다. 체중, 사료 및 음수섭취량에서 대조군과 시험물질간의 영향은 없는 것으로 판단되었다. 혈중 호르몬 농도에서 혈중 에스트로겐의 농도는 음성대조군, 양성대조군 및 에틸 파라벤 투여군에서 대조군에 비해 유의성있는 감소를 보였고, 이외의 시험물질에서 차이는 관찰되지 않았다. 또한, 혈중 난포자극 호르몬 및 혈중 황체형성 호르몬의 변화도 관찰되지 않아 파라벤류에 의한 혈중 에스트로겐, 난포자극 호르몬 및 황체형성 호르몬의 변화는 없는 것으로 사료되었다. 장기중량에서 생식기계를 제외한 장기에서 시험물질에 의한 영향은 없는 것으로 사료되었으며, 또한 난소 및 질의 중량에서 시험물질과 연관된 변화는 없는 것으로 판단되었다. 그러나 자궁의 wet weight 및 blotted weigh에서는 각 시험물질군에서 대조군에 대해 증가가 관찰되었다. 이소부틸 파라벤 투여군은 모든 용량군이 자궁중량에서 유의성있는 증가를 보여 가장 에스트로겐성 영향이 큰 것으로 사료되었고, 250 및 1,000 mg/kg 투여군에서 유의성있는 증가를 보인 이소프로필 투여군이 그 다음으로 에스트로겐 영향이 큰 것으로 판단되었다. 부검결과, 자궁의 확장정도는 자궁의 중량에서 관찰된 바와 대부분 일치하였으며, 조직병리학적 검사를 통해 자궁상피세포를 관찰한 결과, 이소부틸 파라벤 투여군이 가장 높은 세포질과 핵의 비율을 나타내었으며, 이소프로필 파라벤 및 부틸 파라벤 1,000 mg/kg 투여군에서는 다소 작게 관찰되었다. 자궁의 영상분석결과, 대부분의 시험물질투여군에서 자궁직경의 장축 및 단축, 자궁벽의 최소 및 최대치에서 대조군에 대해 유의성있는 변화가 없거나 감소하는 경향을 나타냈으나, 이소부틸 파라벤 투여군의 경우에는 증가하는 경향을 나타내었다. 이상의 결과를 토대로, 에틸 파라벤, 프로필 파라벤, 이소프로필 파라벤, 부틸 파라벤, 이소부틸 파라벤에서 자궁비대 반응이 관찰되어 파란벤류의 물질은 내분비 장애물질로서 검토되어야 할 것으로 사료되며, 이소부틸 파라벤이 가장 높은 에스트로겐성 영향을 주는 것으로 판단되었다.

• Biomolecules & Therapeutics
• /
• 제22권4호
• /
• pp.347-354
• /
• 2014

Larrea nitida is a plant that belongs to the Zygophyllaceae family and is widely used in South America to treat inflammatory diseases, tumors and menstrual pain. However, its pharmacological activity remains unclear. In this study we evaluated the property of selective estrogen receptor modulator (SERM) of Larrea nitida extracts (LNE) as a phytoestrogen that can mimic, modulate or disrupt the actions of endogenous estrogens, depending on the tissue and relative amount of other SERMs. To investigate the property of SERM of LNE, we performed MCF-7 cell proliferation assays, estrogen response element (ERE)-luciferase reporter gene assay, human estrogen receptor (hER) binding assays and in vivo uterotrophic assay. To gain insight into the active principles, we performed a bioassay-guided analysis of LNE employing solvents of various polarities and using classical column chromatography, which yielded 16 fractions (LNs). LNE showed high binding affinities for $hER{\alpha}$ and $hER{\beta}$ with $IC_{50}$ values of $1.20{\times}10^{-7}$ g/ml and $1.00{\times}10^{-7}$ g/ml, respectively. LNE induced $17{\beta}$-estradiol (E2)-induced MCF-7 cell proliferation, however, it reduced the proliferation in the presence of E2. Furthermore, LNE had an atrophic effect in the uterus of immature rats through reducing the expression level of progesterone receptor (PR) proteins. LN08 and LN10 had more potent affinities for binding on $hER{\alpha}$ and ${\beta}$ than other fractions. Our results indicate that LNE had higher binding affinities for $hER{\beta}$ than $hER{\alpha}$, and showed SERM properties in MCF-7 breast cancer cells and the rat uterus. LNE may be useful for the treatment of estrogen-related conditions, such as female cancers and menopause.