title: Honokiol attenuates torsion/detorsion-induced testicular injury in rat testis by way of suppressing endoplasmic reticulum stress-related apoptosis.
abstract: OBJECTIVE
  To investigate the protective effect of honokiol, a phytochemical used in traditional medicine, on testicular injury after torsion/detorsion (T/D) in a rat model. Testicular torsion is a medical emergency that can cause impairment of semen quality and permanent testicular atrophy or loss.
  
  
  METHODS
  Male Wistar rats were randomized to each time point of each group (n = 6/time point/group). After 2 hours of torsion, the testes were counter-rotated to the natural position. The rats in each group underwent a sham operation, T/D, or T/D with honokiol treatment (5 mg/kg and 10 mg/kg intraperitoneally, immediately before detorsion). Bilateral orchiectomy was performed at 6 and 24 hours and 3 months after detorsion. The testes were examined histologically. Apoptosis and endoplasmic reticulum stress were detected by Western blot.
  
  
  RESULTS
  Histologic examination revealed that testicular T/D induced acute injury after 6 and 24 hours, and spermatogenesis was decreased at 3 months of follow-up. At 24 hours after T/D, increases were found in the activation of apoptosis-related molecules [poly (ADP-ribose) polymerase and caspases 3 and 7], and the expression levels of endoplasmic reticulum stress-associated molecules (phosphorylated-eukaryotic translation initiation factor 2 subunit α and CCAAT/enhancer-binding protein homologous protein). These increases were significantly reversed with honokiol treatment. Furthermore, honokiol effectively reversed the inhibition of spermatogenesis in testes treated with T/D for 3 months.
  
  
  CONCLUSIONS
  The results of our study have shown that the endoplasmic reticulum stress-related apoptotic pathway is involved in testicular injury after testicular T/D. It remains to be determined whether alterations in this pathway would have a protective affect against reperfusion damage.
authors.affiliation: Institute of Toxicology, National Taiwan University Hospital, and National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Kuo-How
authors.initials: KH
authors.lastname: Huang
authors.forename: Te-I
authors.initials: TI
authors.lastname: Weng
authors.forename: Hsin-Yi
authors.initials: HY
authors.lastname: Huang
authors.forename: Kuo-Dong
authors.initials: KD
authors.lastname: Huang
authors.forename: Wei-Chou
authors.initials: WC
authors.lastname: Lin
authors.forename: Shyh-Chyan
authors.initials: SC
authors.lastname: Chen
authors.forename: Shing-Hwa
authors.initials: SH
authors.lastname: Liu
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects* / Q000502:physiology; D001713:Biphenyl Compounds / Q000494:pharmacology*; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D004721:Endoplasmic Reticulum / Q000187:drug effects / Q000502:physiology*; D017705:Lignans / Q000494:pharmacology*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000517:prevention & control; D013086:Spermatic Cord Torsion / Q000503:physiopathology*; D013091:Spermatogenesis / Q000502:physiology; D000498:Allyl Compounds; D010636:Phenols
chemical_list: D001713:Biphenyl Compounds; D004365:Drugs, Chinese Herbal; D017705:Lignans; C005499:honokiol; D000498:Allyl Compounds; D010636:Phenols