title: Matrine inhibits mouse sperm function by reducing sperm [Ca2+]i and phospho-ERK1/2.
abstract: BACKGROUND
  Matrine is a bioactive alkaloid that has a variety of pharmacological effects and is widely used in Chinese medicine. However, its effects on male reproduction are not well known. In this study, we aimed to investigate the in vitro toxicity of matrine on mature mouse sperm.
  
  
  METHODS
  Mouse cauda epididymal sperm were exposed to matrine (10-200 µM) in vitro. The viability, motility, capacitation, acrosome reaction and fertilization ability of the mouse sperm were examined. Furthermore, the intracellular calcium concentration ([Ca(2+)]i), calcium (Catsper) and potassium (Ksper) currents, and phosphorylation of extracellular signal regulated kinases 1/2 (p-ERK1/2) of the sperm were analyzed.
  
  
  RESULTS
  After exposure to 100 µM or more of matrine, mouse cauda epididymal sperm exhibited a significant reduction in total motility, progressive motility, linear velocity and acrosome reaction rate induced by Ca(2+) ionophore A23187. As a result, the fertilization ability of mouse sperm was remarkably decreased by matrine. Our data further demonstrated that matrine significantly reduced sperm [Ca(2+)]i and [Ca(2+)]i-related p-ERK1/2; however, both the CatSper and KSper currents, which are thought to interactively regulate Ca(2+) influx in sperm, were not affected by matrine.
  
  
  CONCLUSIONS
  Our findings indicate that matrine inhibits mouse sperm function by reducing sperm [Ca(2+)]i and suppressing the phosphorylation of ERK1/2.
authors.affiliation: Institute of Life Science, Nanchang University, Nanchang, PR China.
authors.forename: Tao
authors.initials: T
authors.lastname: Luo
authors.forename: Qian-xing
authors.initials: QX
authors.lastname: Zou
authors.forename: Yuan-qiao
authors.initials: YQ
authors.lastname: He
authors.forename: Hua-feng
authors.initials: HF
authors.lastname: Wang
authors.forename: Na
authors.initials: N
authors.lastname: Li
authors.forename: Xu-hui
authors.initials: XH
authors.lastname: Zeng
mesh_terms: D020101:Acrosome Reaction / Q000187:drug effects; D000470:Alkaloids / Q000494:pharmacology*; D000814:Aniline Compounds / Q000737:chemistry; D000818:Animals; D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D005260:Female; D005307:Fertilization in Vitro / Q000187:drug effects; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008856:Microscopy, Fluorescence; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D010766:Phosphorylation / Q000187:drug effects; D011188:Potassium / Q000378:metabolism; D011807:Quinolizines / Q000494:pharmacology*; D013081:Sperm Motility / Q000187:drug effects; D013094:Spermatozoa / Q000737:chemistry / Q000187:drug effects* / Q000378:metabolism; D014966:Xanthenes / Q000737:chemistry; D000093842:Matrines
chemical_list: D000470:Alkaloids; D000814:Aniline Compounds; C409648:Fluo 4; D011807:Quinolizines; D014966:Xanthenes; D000001:Calcimycin; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D011188:Potassium; D002118:Calcium; D000093842:Matrines