Identification of sperm mRNA biomarkers associated with testis injury during preclinical testing of pharmaceutical compounds.
The human testis is sensitive to toxicant-induced injury but current methods for detecting adverse effects are limited, insensitive and unreliable. Animal studies use sensitive histopathological endpoints to assess toxicity, but require testicular tissue that is not available during human clinical trials. More sensitive and reliable molecular biomarkers of testicular injury are needed to better monitor testicular toxicity in both clinical and preclinical. Adult male Wistar Han rats were exposed for 4weeks to compounds previously associated with testicular injury, including cisplatin (0, 0.2, 0.3, or 0.4mg/kg/day), BI665915 (0, 20, 70, 100mg/kg/d), BI665636 (0, 20, 100mg/kg/d) or BI163538 (0, 70, 150, 300mg/kg/d) to evaluate reproductive toxicity and assess changes in sperm mRNA levels. None of the compounds resulted in any significant changes in body, testis or epididymis weights, nor were there decreases in testicular homogenization resistant spermatid head counts. Histopathological evaluation found that only BI665915 treatment caused any testicular effects, including minor germ cell loss and disorganization of the seminiferous tubule epithelium, and an increase in the number of retained spermatid heads. A custom PCR-array panel was used to assess induced changes in sperm mRNA. BI665915 treatment resulted in a significant increase in clusterin (Clu) levels and decreases in GTPase, IMAP family member 4 (Gimap4), prostaglandin D2 synthase (Ptgds) and transmembrane protein with EGF like and two follistatin like domains 1 (Tmeff1) levels. Correlation analysis between transcript levels and quantitative histopathological endpoints found a modest association between Clu with retained spermatid heads. These results demonstrate that sperm mRNA levels are sensitive molecular indicators of testicular injury that can potentially be translated into a clinical setting.
Division of Urology, Rhode Island Hospital, Providence, RI, USA; Department of Pathology and Laboratory Medicine, Brown University, Providence, RI, USA.
Edward
E
Dere
Department of Pathology and Laboratory Medicine, Brown University, Providence, RI, USA.
Daniel J
DJ
Spade
Department of Pathology and Laboratory Medicine, Brown University, Providence, RI, USA.
Susan J
SJ
Hall
Boehringer Ingelheim Pharmaceuticals, Ridgefield, CT, USA.
Aimee
A
Altemus
Boehringer Ingelheim Pharmaceuticals, Ridgefield, CT, USA.
James D
JD
Smith
Boehringer Ingelheim Pharmaceuticals, Ridgefield, CT, USA.
Jonathan A
JA
Phillips
Boehringer Ingelheim Pharmaceuticals, Ridgefield, CT, USA.
Jeffrey S
JS
Moffit
Boehringer Ingelheim Pharmaceuticals, Ridgefield, CT, USA.
Kerry T
KT
Blanchard
Department of Pathology and Laboratory Medicine, Brown University, Providence, RI, USA. Electronic address: kim_boekelheide@brown.edu.
Kim
K
Boekelheide
D000081:Acetamides / Q000633:toxicity*; D000818:Animals; D002945:Cisplatin / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D004353:Drug Evaluation, Preclinical / Q000379:methods; D008297:Male; D009929:Organ Size / Q000187:drug effects / Q000502:physiology; D010069:Oxadiazoles / Q000633:toxicity*; D012333:RNA, Messenger / Q000096:biosynthesis*; D051381:Rats; D017208:Rats, Wistar; D013091:Spermatogenesis / Q000187:drug effects / Q000502:physiology; D013094:Spermatozoa / Q000187:drug effects* / Q000378:metabolism* / Q000473:pathology; D013737:Testis / Q000187:drug effects* / Q000378:metabolism* / Q000473:pathology
C000597466:2-(4-(3-(1-(4-(2-aminopyrimidin-5-yl)phenyl)-1-cyclopropylethyl)-(1,2,4)oxadiazol-5-yl)pyrazol-1-yl)-N,N-dimethylacetamide; D000081:Acetamides; D010069:Oxadiazoles; D012333:RNA, Messenger; D002945:Cisplatin
Biomarkers; RNA; Sperm; Testis