Proteomic analysis of seminal plasma from asthenozoospermia patients reveals proteins that affect oxidative stress responses and semen quality

Abstract

Asthenozoospermia (AS) is a common cause of human male infertility. In one study, more than 80% of the samples from infertile men had reduced sperm motility. Seminal plasma is a mixture of secretions from the testis, epididymis and several male accessory glands, including the prostate, seminal vesicles and Cowper's gland. Studies have shown that seminal plasma contains proteins that are important for sperm motility. To further explore the pathophysiological character of AS, we separated the seminal plasma proteins from AS patients and healthy donors using sodium dodecyl sulfate polyacrylamide gel electrophoresis and in-gel digestion, and then subjected the proteins to liquid chromatography-mass spectrometry (LC-MS/MS) analysis. A total of 741 proteins were identified in the seminal plasma, with a false discovery rate of 3.3%. Using spectral counting, we found that 45 proteins were threefold upregulated and 56 proteins were threefold downregulated in the AS group when compared with the control. Most of these proteins originated from the epididymis and prostate. This study identified a rich source of biomarker candidates for male infertility and indicates that functional abnormalities of the epididymis and prostate can contribute to AS. We identified DJ-1-a protein that has been shown elsewhere to be involved in the control of oxidative stress (OS)-as a downregulated protein in AS seminal plasma. The levels of DJ-1 in AS seminal plasma were about half of those in the control samples. In addition, the levels of reactive oxygen species were 3.3-fold higher in the AS samples than in the controls. Taken together, these data suggest that downregulation of DJ-1 is involved in OS in semen, and therefore affects the quality of the semen.

The protective effects of α-ketoacids against oxidative stress on rat spermatozoa in vitro

“…Clinical studies showed that oral antioxidant treatment appeared to improve sperm DNA integrity and outcomes of in vitro fertilization with intracytoplasmic sperm injection among patients with sperm DNA damage or other male infertility [9,10]. In asthenozoospermia patients, the high level of ROS in semen may be associated with the downregulation of a DJ-1 protein, which is involved in the control of oxidative stress [11].…”

Molecular heterogeneity of gelatin-binding proteins from human seminal plasma

“…[1]. Introducing proteomic analysis of human seminal fluid has led to more detailed analysis and has indicated a large number of extracellular proteins, proteases and other proteins secreted by testes, prostate and other male accessory glands [2][3][4][5]. However, the structure-function relationship of seminal plasma proteins at the molecular level and the relation of more basic questions to particular clinical end points is still insufficiently explored.…”

Proteomics of human seminal plasma: Identification of biomarker candidates for fertility and infertility and the evolution of technology

“…Yamakawa et al (2007) identified up to 501 polypeptide spots in SP from fertile men by a proteomic approach based on 2D-differential gel electrophoresis (2D-DIGE), and used this normalized standard map of SP proteins to characterize the differences in the proteic expression between fertile and azoospermic patients. Wang et al (2009), on the other hand, identified 625 proteins in SP from fertile men by LC-MS/MS analysis. They identified 45 up-regulated proteins and 56 down-regulated proteins in a group of asthenozoospermic patients compared with the control subjects.…”

“…Moreover, the quantities of two epididymal secretory proteins, protein E1 and epididymal secretory protein E4, were increased in asthenozoospermic SP. This study identified a rich source of biomarker candidates for male infertility, and suggested that functional abnormalities of the epididymis, prostate, and seminal vesicles can impact sperm quality (Wang et al, 2009). …”

“…The flight time of each ionized fragment is proportional to the square root of the m/z ratio. As the charge (z) of the ionized proteins is often þ1, the m/z value is often equal to the mass (2003) MALDI-TOF Impaired spermatogenesis Utleg et al (2003) LCMS/MS Prostasome Fung et al (2004) MALDI-TOF; LC-MS/MS Healthy fertile men Pilch and Mann (2006) MALDI-TOF; LTQ-FT Healthy fertile man Yang et al (2007) SELDI-TOF Biomarkers of oligospermia Yamakawa et al (2007) LCMS/MS Infertile versus fertile men Bai et al (2008) SELDI-TOF Severe oligospermia versus healthy fertile men Kumar et al (2008) MALDI-TOF Heparin binding proteins in human seminal plasma Kumar et al (2009) MALDI-TOF Heparin binding proteins in human seminal plasma Wang et al (2009) LCMS/MS Asthenozoospermia Drake et al (2010) LTQ-Orbitrap XL Prostatic secretions Batruch et al (2011) LTQ-Orbitrap XL Post-vasectomy versus healthy fertile men Milardi et al (2012b) LTQ-Orbitrap XL Healthy fertile men Batruch et al (2012) LTQ-Orbitrap XL Non-obstructive azoospermia Kagedan et al (2012) LTQ-Orbitrap XL Prostatitis Molecular Reproduction & Development value. The spectral output produced by MALDI-TOF is represented by a number of protein peaks, which are described by a m/z value on the horizontal axis and by a peak-intensity value on the vertical axis (Schuchardt and Sickmann, 2007).…”