Zhuo Liu

Publications (3)6.46 Total impact

• Article: Interaction between neurotrophin 4 and gonadotrophin in bovine oviducts.

  Yongfeng Sun, Jing Zhang, Chunjin Li, Dong Wang, Yonghe Ma, Yanling Sun, Zhuo Liu, Chunqiang Wang, Xu Zhou
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  ABSTRACT: The expression and localization of neurotrophin 4 (NT4) and its receptor, tyrosine kinase B (TRKB), in the bovine oviduct, and their interaction with gonadotrophins in bovine oviduct epithelial cells (BOECs), were examined. Transcripts for NT4 and TRKB were detected by reverse transcription polymerase chain reaction (RT-PCR) in bovine oviducts in the follicular and luteal phases, and their proteins were immunolocalized in BOECs. Based on real time PCR, NT4 mRNA did not differ significantly between the two phases of the cycle, although TRKB mRNA expression was higher (P < 0.05) in the luteal phase than that in follicular phase. The BOECs were treated with various concentrations of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in vitro; for NT4, mRNA and protein were higher (P < 0.05) than those in the control (based on real time PCR and enzyme-linked immunosorbent assay (ELISA) assays). The effects of NT4 and the TRKB inhibitor (K252a) on the expression of LH receptor (LHR) and FSH receptor (FSHR) in the oviduct epithelial cells were also studied using a monolayer culture model. Expression levels of LHR and FSHR mRNA in BOECs treated with various concentrations of NT4 were higher (P < 0.05) than those in the control. However, these expressions were blocked by treatment with K252α. We concluded that neurotrophin 4 may have a role in regulating the function of bovine oviducts by interacting with gonadotrophins.
  Theriogenology 03/2012; 78(1):39-48. · 1.96 Impact Factor
• Article: The expression and putative role of brain-derived neurotrophic factor and its receptor in bovine sperm.

  C Li, X Zhu, C Wang, Zhuo Liu, W Li, Chen Lu, Xu Zhou
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  ABSTRACT: The neurotrophin family of proteins promote the survival and differentiation of nerve cells and are thought to play an important role in development of reproductive tissues. The objective of the present study was to detect the presence of Brain-derived neurotrophic factor (BDNF) and its receptor TrkB in bovine sperm, and explore the potential role of BDNF in sperm function. We demonstrated that both the neorotrophin BDNF and the tyrosine kinase receptor protein TrkB were expressed in ejaculated bovine sperm. Furthermore, BDNF per se was secreted by sperm. Insulin and leptin secretion by bovine sperm were increased (P < 0.01) when cells were exposed to exogenous BDNF, whereas insulin was decreased by K252a. Therefore, we inferred that BDNF could be a regulator of sperm secretion of insulin and leptin through the TrkB receptor. Sperm viability and mitochondrial activity were both decreased (P < 0.05) when the BDNF/TrkB signaling pathway was blocked with K252a. Furthermore, BDNF promoted apoptosis of bovine sperm through TrkB binding (P < 0.05). In conclusion, these observations provided evidence that BDNF secreted by bovine sperm was important in regulation of insulin and leptin secretion in ejaculated bovine sperm. Furthermore, BDNF may affect sperm mitochondrial activity and apoptosis, as well as their viability.
  Theriogenology 02/2012; 77(3):636-43. · 1.96 Impact Factor
• Article: Expression of brain-derived neurotrophic factor in mature spermatozoa from fertile and infertile men.

  Lianwen Zheng, Chunjin Li, Yongfeng Sun, Zhuo Liu, Xu Zhou
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  ABSTRACT: Neurotrophins, a family of growth factor, are not only required for the survival and differentiation of the nervous system but also important for the development of reproductive tissues. We identified the expression of brain-derived neurotrophic factor (BDNF) transcript and protein in human spermatozoa. The presence of BDNF in human spermatozoa was investigated using RT-PCR, immunofluorescence and Western blotting. Real-time PCR and ELISA were employed to determine expression levels of BDNF. BDNF mRNA and protein were detected in human spermatozoa. Immunofluorescence staining showed that BDNF protein was localized in the head, neck, and tail of human spermatozoa. The amount of BDNF mRNA expressed in spermatozoa of oligoasthenozoospermic group was lower than that of fertile group (P < 0.05). The concentration of BDNF in seminal plasma from oligoasthenozoospermic group (2.8 ± 0.7 ng/ml) was both lower than that from fertile group (3.6 ± 0.4 ng/ml) and asthenozoospermic group (3.4 ± 0.5 ng/ml) (P < 0.05). The data showed that the decrease in BDNF transcript and protein in oligoasthenozoospermic group may be associated with pathogenesis in some types of male infertility.
  Clinica chimica acta; international journal of clinical chemistry 01/2011; 412(1-2):44-7. · 2.54 Impact Factor