title: Aquaporin7 plays a crucial role in tolerance to hyperosmotic stress and in the survival of oocytes during cryopreservation.
abstract: Hyperosmotic stress may induce apoptosis of different cells. However, oocytes show tolerance to osmotic stress during cryopreservation by vitrification, which is an assisted reproductive technique. The underlying mechanism is still not understood. Here, we demonstrated that hyperosmosis produced by high concentrations of cryoprotectants, including DMSO, ethylene glycol and sucrose, significantly upregulated the protein levels of aquaporin (AQP) 7, but not AQP3 and AQP9, in mouse oocytes. Knockdown of AQP7 expression by siRNA-injection significantly reduced the survival of oocytes after vitrification. In oocytes, AQP7 was shown to bind with F-actin, a protein involved in almost all biological events. Moreover, we found that hyperosmosis could upregulate the phosphorylation levels of CPE-binding protein (CPEB) and Aurora A. Inhibition of the PI3K and PKC pathways blocked the hyperosmosis-induced upregulation of AQP7 and the phosphorylation of CPEB and Aurora A in oocytes. In conclusion, hyperosmosis could upregulate the expression of AQP7 via Aurora A/CPEB phosphorylation mediated by the PI3K and PKC pathways, and upregulation of AQP7 plays an important role in improving of tolerance to hyperosmotic stress and survival of oocytes during cryopreservation by vitrification.
authors.affiliation: Center of Reproductive Medicine, the International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.|Institute of Embryo-Fetal Original Adult Disease Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Ya-Jing
authors.initials: YJ
authors.lastname: Tan
authors.affiliation: The Key Laboratory of Reproductive Genetics, Ministry of Education (Zhejiang University), Hangzhou, China.
authors.forename: Xue-Ying
authors.initials: XY
authors.lastname: Zhang
authors.affiliation: Center of Reproductive Medicine, the International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.|Institute of Embryo-Fetal Original Adult Disease Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Guo-Lian
authors.initials: GL
authors.lastname: Ding
authors.affiliation: Center of Reproductive Medicine, the International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.|Institute of Embryo-Fetal Original Adult Disease Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Rong
authors.initials: R
authors.lastname: Li
authors.affiliation: Center of Reproductive Medicine, the International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.|Institute of Embryo-Fetal Original Adult Disease Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Li
authors.initials: L
authors.lastname: Wang
authors.affiliation: Center of Reproductive Medicine, the International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.|Institute of Embryo-Fetal Original Adult Disease Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Li
authors.initials: L
authors.lastname: Jin
authors.affiliation: Institute of Embryo-Fetal Original Adult Disease Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai, China.|The Key Laboratory of Reproductive Genetics, Ministry of Education (Zhejiang University), Hangzhou, China.
authors.forename: Xian-Hua
authors.initials: XH
authors.lastname: Lin
authors.affiliation: Center of Reproductive Medicine, the International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Gao
authors.affiliation: The Key Laboratory of Reproductive Genetics, Ministry of Education (Zhejiang University), Hangzhou, China.|Department of Pathology &Pathophysiology, School of Medicine, Zhejiang University, Hangzhou, China.
authors.forename: Jian-Zhong
authors.initials: JZ
authors.lastname: Sheng
authors.affiliation: Center of Reproductive Medicine, the International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.|Institute of Embryo-Fetal Original Adult Disease Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai, China.|The Key Laboratory of Reproductive Genetics, Ministry of Education (Zhejiang University), Hangzhou, China.
authors.forename: He-Feng
authors.initials: HF
authors.lastname: Huang
mesh_terms: D000199:Actins / Q000378:metabolism; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D020346:Aquaporins / Q000037:antagonists & inhibitors / Q000096:biosynthesis* / Q000235:genetics; D002470:Cell Survival / Q000187:drug effects; D015925:Cryopreservation; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D019855:Ethylene Glycol / Q000493:pharmacokinetics; D051379:Mice; D009865:Oocytes / Q000187:drug effects* / Q000502:physiology; D009997:Osmotic Pressure / Q000187:drug effects / Q000502:physiology*; D019869:Phosphatidylinositol 3-Kinases / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics; D027724:Reproductive Techniques, Assisted; D013395:Sucrose / Q000494:pharmacology; D058989:Vitrification / Q000187:drug effects
chemical_list: D000199:Actins; C491927:Aqp7 protein, mouse; D020346:Aquaporins; D034741:RNA, Small Interfering; D013395:Sucrose; D019869:Phosphatidylinositol 3-Kinases; D019855:Ethylene Glycol; D004121:Dimethyl Sulfoxide