title: [Radiation-induced oxidative stress and claudin-11 mRNA expression in the testis].
abstract: OBJECTIVE
  To investigate the role of claudin-11, a tight junction component of Sertoli cells, in spermatogenic dysfunction induced by oxidative stress in mice exposed to local radiation.
  
  
  METHODS
  We randomly allocated 48 male Kunming mice to a blank control group (A) and three radiation groups (B, C and D) of equal number, the latter three exposed to local radiation of the lower abdomen with 2 Gy, 6 Gy and 10 Gy of 60Co-gamma-ray, respectively, to induce oxidative stress. Four weeks later, we killed the animals, obtained their body and testis weights, observed the histological changes of the testis by HE staining, measured the levels of serum FSH, testosterone and LH by ELISA, and determined the mRNA levels of claudin-11 and inhibin beta B in Sertoli cells by real time quantitative PCR.
  
  
  RESULTS
  After exposure to 60Co-gamma-ray radiation, the testis weights were (129.4 +/- 10.81), (87.5 +/- 16.83) and (56.1 +/- 12.36) mg in groups B, C and D, significantly decreased as compared with (182.9 +/- 8.43) mg in group A (P < 0.05); the testis indexes were (3.39 +/- 0.57), (2.46 +/- 0.46) and (1.63 +/- 0.44) mg/g in groups B, C and D, remarkably lower than (4.28 +/- 0.31) mg/g in group A (P < 0.01). Histological analysis revealed obviously decreased diameters of seminiferous tubules, reduced seminiferous epithelia and disarranged spermatogenic cells in the three radiation groups. The tubule differentiation indexes (TDI) were markedly lower in groups B, C and D than in A (P < 0.01). The levels of serum FSH were (6.74 +/- 1.95), (8.41 +/- 2.44) and (10.93 +/- 3.16) IU/L in groups B, C and D, 1.9 times higher in D than in A. With increased dose of radiation, the mRNA levels of inhibin beta in the testis tissue were descended, while the transcription levels of claudin-11 elevated, significantly higher in groups C and D than in A (P < 0.01).
  
  
  CONCLUSIONS
  Local radiation-induced testicular oxidative stress can decrease the mRNA level of inhibin beta , increase serum FSH, damage Sertoli cells and elevate the expression of claudin-11 in the testis tissue. Increased claudin-11 and serum FSH may delay the cyclical restitution of hemo-testicular barrier and reduce the number of meiotic spermatocytes in the seminiferous epithelium, which consequently leads to male infertility.
authors.affiliation: Department of Urology/Open Laboratory for Key Clinical Disciplines of Henan Higher Education Institutions, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, China.
authors.forename: Wei-Xing
authors.initials: WX
authors.lastname: Zhang
authors.forename: Jun-Chang
authors.initials: JC
authors.lastname: Qin
authors.forename: Rui
authors.initials: R
authors.lastname: Wang
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
mesh_terms: D000818:Animals; D057167:Claudins / Q000378:metabolism*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D018384:Oxidative Stress / Q000528:radiation effects*; D012333:RNA, Messenger / Q000235:genetics; D012671:Seminiferous Tubules / Q000378:metabolism / Q000528:radiation effects; D012708:Sertoli Cells / Q000378:metabolism; D013090:Spermatocytes / Q000378:metabolism / Q000528:radiation effects; D013091:Spermatogenesis; D013737:Testis / Q000378:metabolism* / Q000528:radiation effects*
chemical_list: D057167:Claudins; C492354:Cldn11 protein, mouse; D012333:RNA, Messenger