A 3D Mini-Testis Model for Reproductive Toxicity Testing

Details

• Personal Author:
  Yu X
• Description:
  Occupational exposure to reproductive toxicants occurs via inhalation, skin absorption, or ingestion. Thousands of chemicals exist in the workplace; there is limited or no toxicological information including reproductive and developmental (R/D) toxicity available for many industrial chemicals. Toxicity testing on animals represents one of the largest uses of animals yet it also has been an extraordinarily challenging area in which to implement in vitro alternatives. Since the report "Toxicity Testing in the 21st Century" by the National Research Council (NRC, 2007) envisioned that in vivo animal testing can eventually be replaced by a combination of in silico and in vitro approaches, the demand to identify in vitro models for R/D toxicity has grown. In this proposal, we established an in vitro "mini-testis" model from testicular cell lines, which finally eliminated the need of animals. We created a niche environment in which spermatogonial stem cells could be maintained and directed to proliferate and undergo meiosis and complete spermatogenesis. Based on this novel in vitro model, we established a toxicity-based high throughput assay. We selected 32 known reproductive toxicants and applied the high-throughput assay to compared their toxicity across multiple in vitro cell culture models. The comparison between the in vitro toxicity (IC50) and in vivo reproductive toxicity (lowest observed adverse effect level on the reproductive system) was conducted. We observed a strongest correlation of IC50 of the cell viability between this in vitro testicular co-culture model and in vivo testing results, but not with any single testicular cell culture models such as spermatogonia, Sertoli cell or Leydig cells. We have demonstrated that this novel in vitro co-culture model may be useful in screening testicular toxicants in a wide concentration range and prioritize chemicals for future experiments. Furthermore, we developed an automated multi-parametric High Content Analysis (HCA) and high throughput screening assays, representing a wide spectrum of cellular and molecular events that potentially lead to impaired male reproductive function, including nuclear morphology, DNA content, cytoskeletal integrity, cell cycle, and DNA damage responses in a dose and time- dependent manner. We applied this validated HCA approaches to characterize and compare the testicular toxicities of bisphenol A (BPA) and three selected commercially available BPA analogues: bisphenol S, bisphenol AF and tetrabromobisphenol A. Our results demonstrated that this novel in vitro model provides a cost-efficient screen tool for potential R/D toxicity of chemicals in the workplace, and will provide importance data for establishing exposure limit in workplace for effective prevention of R/D toxicity in workplace such as MANUFACTURING, MINING, OIL AND GAS EXTRACTION and PUBLIC SAFETY. The research conducted so far has generated 12 publications, 9 conference proceedings, and generated testicular toxicity data regarding the chemicals in workplace, and provided data for risk assessment. This funding opportunity also supported the career development of Dr. Yu in reproductive toxicology, his long-term effort in seeking and promoting in vitro animal alternatives. Therefore, this proposal met the mission of Cancer, Reproductive, and Cardiovascular Research Program (CRC). [Description provided by NIOSH]
• Subjects:
  Laboratories Occupational Exposure Occupational Health Safety Spermatogenesis Urogenital System
• Keywords:
  Bisphenol A Cellular Effects Dose Response In Vitro Study Laboratory Animals Occupational Exposure Reproductive Effects Testes
• Series:
  Grant Final Reports
• Publisher:
  National Institute for Occupational Safety and Health
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Final Grant Report
• Place as Subject:
  Georgia ; OSHA Region 4
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  OEP - Office of Extramural Programs
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  1-41
• NIOSHTIC Number:
  nn:20053954
• NTIS Accession Number:
  PB2019-100395
• Citation:
  Atlanta, GA: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, R21-OH-010473, 2016 Nov; :1-41
• Contact Point Address:
  Xiaozhong Yu, Environmental Health Science Building, 150 East Green Street, Athens, GA 30602
• Email:
  yuxz@uga.edu
• CAS Registry Number:
  2,2-Bis(4-hydroxyphenyl)propane (CAS RN 80-05-7)
• Federal Fiscal Year:
  2017
• Performing Organization:
  University of Georgia, Athens
• Peer Reviewed:
  False
• Start Date:
  20130901
• Source Full Name:
  National Institute for Occupational Safety and Health
• End Date:
  20160831
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:a4d6e7bc6c32831f761b4a2f389f595b561ea58a5d7bcc0cfb950b7af04bea4961f90cfc8038c040b04278efd62c6a07b0d34b1eee808a6fc1950c5928c3d8b5
• Download URL:
  https://stacks.cdc.gov/view/cdc/218788/cdc_218788_DS1.pdf
• File Type:
  [PDF - 5.33 MB ]