Advanced glycation end products inhibit testosterone secretion by rat Leydig cells by inducing oxidative stress and endoplasmic reticulum stress.
Diabetes severely impairs male reproduction. The present study assessed the effects and mechanisms of action of advanced glycation end products (AGEs), which play an important role in the development of diabetes complications, on testosterone secretion by rat Leydig cells. Primary rat Leydig cells were cultured and treated with AGEs (25, 50, 100 and 200 µg/ml). Testosterone production induced by human chorionic gonadotropin (hCG) was determined by ELISA. The mRNA and protein expression levels of steroidogenic acute regulatory protein (StAR), cholesterol side-chain cleavage enzyme (P450scc) and 3β-hydroxysteroid dehydrogenase (3β-HSD), which are involved in testosterone biosynthesis, were measured by reverse transcription-quantitative PCR and western blot analyssi, respectively. Reactive oxygen species (ROS) production in Leydig cells was measured using the dichlorofluorescein diacetate (DCFH-DA) probe. The expression levels of endoplasmic reticulum stress-related proteins [C/EBP homologous protein (CHOP) and glucose-regulated protein 78 (GRP78)] in the Leydig cells were measured by western blot analysis. We found that the AGEs markedly suppressed testosterone production by rat Leydig cells which was induced by hCG in a concentration-dependent manner compared with the control (P<0.01). The mRNA and protein expression levels of StAR, 3β-HSD and P450scc were downregulated by the AGEs in a dose-dependent manner compared with the control (P<0.01). The antioxidant agent, N-acetyl‑L‑cysteine (NAC), and the endoplasmic reticulum stress inhibitor, tauroursodeoxycholic acid (TUDCA), reversed the inhibitory effects of AGEs. In addition, the content of ROS in Leydig cells treated with AGEs increased significantly. The expression levels of CHOP and GRP78 were markedly upregulated by the AGEs in the Leydig cells. From these findings, it can be concluded that AGEs inhibit testosterone production by rat Leydig cells by inducing oxidative stress and endoplasmic reticulum stress.
Modern Biochemistry Center, Guangdong Ocean University, Zhanjiang, Guangdong 524088, P.R. China.
Yun-Tao
YT
Zhao
Institute of Plastic Surgery, Affiliated Hospital of Guangdong Medical College, Zhanjiang, Guangdong 524001, P.R. China.
Ya-Wei
YW
Qi
Department of Biology, Guangdong Medical College, Zhanjiang, Guangdong 524023, P.R. China.
Chuan-Yin
CY
Hu
Modern Biochemistry Center, Guangdong Ocean University, Zhanjiang, Guangdong 524088, P.R. China.
Shao-Hong
SH
Chen
Modern Biochemistry Center, Guangdong Ocean University, Zhanjiang, Guangdong 524088, P.R. China.
You
Y
Liu
D015067:17-Hydroxysteroid Dehydrogenases / Q000235:genetics / Q000378:metabolism; D000111:Acetylcysteine / Q000494:pharmacology; D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D002786:Cholesterol Side-Chain Cleavage Enzyme / Q000235:genetics / Q000378:metabolism; D006063:Chorionic Gonadotropin / Q000494:pharmacology; D000091342:Endoplasmic Reticulum Chaperone BiP; D059865:Endoplasmic Reticulum Stress / Q000187:drug effects*; D017127:Glycation End Products, Advanced / Q000633:toxicity*; D006801:Humans; D007985:Leydig Cells / Q000378:metabolism* / Q000473:pathology*; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects*; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017207:Rats, Sprague-Dawley; D013655:Taurochenodeoxycholic Acid / Q000494:pharmacology; D013739:Testosterone / Q000378:metabolism*; D051742:Transcription Factor CHOP / Q000378:metabolism; D000098682:Steroidogenic Acute Regulatory Protein
D006063:Chorionic Gonadotropin; D000091342:Endoplasmic Reticulum Chaperone BiP; D017127:Glycation End Products, Advanced; C000717247:HSPA5 protein, human; D010750:Phosphoproteins; D012333:RNA, Messenger; D000098682:Steroidogenic Acute Regulatory Protein; D051742:Transcription Factor CHOP; D013739:Testosterone; D013655:Taurochenodeoxycholic Acid; C031655:ursodoxicoltaurine; D015067:17-Hydroxysteroid Dehydrogenases; C044256:3 (or 17)-beta-hydroxysteroid dehydrogenase; D002786:Cholesterol Side-Chain Cleavage Enzyme; D000111:Acetylcysteine