2001 Fiscal Year Final Research Report Summary
Basic and prophylactic study on the toxicity of endocrine disruptors and lifestyle Testicular injury by di-(2-ethylhexyl) phthalate
Project/Area Number |
11470108
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Research Category |
Grant-in-Aid for Scientific Research (B)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Public health/Health science
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Research Institution | Kagawa Medical University |
Principal Investigator |
JITSUNARI fumihiko Kagawa Medical University Professor, 医学部, 教授 (60127561)
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Co-Investigator(Kenkyū-buntansha) |
ITOH masahiro Tokyo Medical University, Professor, 医学部, 教授 (00232471)
ASAKAWA fumiyuki Kurashiki University of Science and the Arts, Professor, 教養学部, 教授 (20159362)
TOKUDA masaaki Kagawa Medical University, Professor, 医学部, 教授 (10163974)
SUNA shigeru Kagawa Medical University, Assinstant Professor, 医学部, 助手 (40253265)
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Project Period (FY) |
1999 – 2001
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Keywords | DEHP / testicular atrophy / vitamin E, C / caffeine / nicotinic acid / ethanol / oxidative stress |
Research Abstract |
Di-(2-ethylhexyl) phthalate (DEHP) is the most common plasticizer for plastics such as polyvinyl chloride (PVC) but suspected to be an endocrine disruptor. Recent studies have shown the toxic effects of DEHP on male reproductive organs such as testicular injury in rats in both mature and growth stages, and this injury has been suggested to be due to oxidative stress induced by mono-(2-ethylhexyl) phthalate (MEHP). Since PVC containing DEHP is widely used in manufacturing consumer goods, food containers, toys, and medical instruments, DEHP contamination is widespread, and the general population is exposed to DEHP in food, water, and air, which arouses concern about human reproductive hazards. In this study, to clarify the effects of chemical substances widely distributed in foods and beverages on the testicular toxicity of DEHP, we administered antioxidants such as vitamins E and C, caffeine, nicotinic acid, and ethanol together with DEHP to rats in the growth stage. In 4- or 5-week-old SD rats given a 1-2% DEHP containing diet for 1-2 weeks, testicular atrophy accompanied by a spermatogenesis developed. Young rats were more susceptible to the testicular toxicity of DEHP. There was a correlation between the blood or testicular MEHP concentration and the degree of DEHP-induced testicular atrophy, suggesting a dose-effect relationship between the dose of MEHP as an active toxicant and testicular injury. In 4-week-old rats given a 2% DEHP containing diet and water supplemented with vitamins E and C, testicular atrophy was definitely inhibited. Water supplemented with caffeine (0.05w/w%), nicotinic acid (0.5 w/w%), or ethanol (2.5 or 5 v/v%) also prevented testicular atrophy in 4-week-old rats given a 1% DEHP containing diet. The action mechanism of these antioxidants was unclear. However, our results suggest the involvement of antioxidant activity and free radical scavenging capacity in the inhibition of DEHP induced testicular injury.
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Research Products
(4 results)