The role of MAPK and FAS death receptor pathways in testicular germ cell apoptosis induced by lead.
The aim of the present study is to investigate gene expression involved in the signal pathway of MAPK and death signal receptor pathway of FAS in lead-induced apoptosis of testicular germ cells. First, cell viabilities were determined by MTT assay. Second, using single cell gel-electrophoresis test (comet assay) and TUNEL staining technique, apoptotic rate and cell apoptosis localization of testicular germ cells were measured in mice treated with 0.15%, 0.3%, and 0.6% lead, respectively. Third, the immunolocalization of K-ras, c-fos, Fas, and active caspase-3 proteins was determined by immunohistochemistry. Finally, changes in the translational levels of K-ras, c-fos, Fas, and active caspase-3 were further detected by western blot analysis. Our results showed that lead could significantly induce testicular germ cell apoptosis in a dose-dependent manner (P<0.01). The mechanisms were closely related to the increased expressions of K-ras, c-fos, Fas, and active caspase-3 in apoptotic germ cells. In conclusion, K-ras/c-fos and Fas/caspase-3 death signaling receptor pathways were involved in the lead-induced apoptosis of the testicular germ cells in mice.
Dong
Shuying
S
Institute of Public Health, Harbin Medical University, Harbin 150086, China.
Liang
Duoping
D
An
Na
N
Jia
Li
L
Shan
Yujuan
Y
Chen
Chao
C
Sun
Kuo
K
Niu
Fei
F
Li
Huiyan
H
Fu
Songbin
S
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D053200:Fas-Associated Death Domain Protein / Q000378:metabolism*; D015870:Gene Expression; D007854:Lead / Q000633:toxicity*; D020935:MAP Kinase Signaling System / Q000187:drug effects / Q000502:physiology*; D008297:Male; D051379:Mice; D020929:Mitogen-Activated Protein Kinase Kinases / Q000378:metabolism*; D013094:Spermatozoa / Q000187:drug effects / Q000502:physiology*
D053200:Fas-Associated Death Domain Protein; D007854:Lead; D020929:Mitogen-Activated Protein Kinase Kinases