Neutral alpha-1,4-glucosidase and fructose levels contribute to discriminating obstructive and nonobstructive azoospermia in Chinese men with azoospermia

Abstract

Nowadays, whether neutral alpha-1,4-glucosidase (NAG) and fructose levels are contributed to discriminating obstructive and nonobstructive azoospermia in Chinese azoospermic patients remains unclear. In this study, we retrospectively analysed the levels of NAG and fructose in 229 patients with obstructive azoospermia and 415 patients with nonobstructive azoospermia from three different medical central. Results indicated that NAG and fructose levels in patients with nonobstructive azoospermia were significantly higher compared with those with obstructive azoospermia (P < 0.05). According to the reference value of NAG and fructose defined by the World Health Organization (WHO, 2010), decreased level of NAG was observed in 77.3% of patients with obstructive azoospermia, which was significantly higher than those with nonobstructive azoospermia (55.2%, P < 0.0001). Low level of fructose was observed in 48.0% of patients with obstructive azoospermia, which is also obviously higher than those with nonobstructive azoospermia (31.8%, P < 0.0001). Moreover, the decrease of both NAG and fructose was only recorded in 3.7% of patients with SCO syndrome, 5.0% of patients with severe hypospermatogenesis and 18.2% of patients with maturation arrest. Therefore, our results indicated that NAG and fructose levels are contributed to discriminating obstructive and nonobstructive azoospermia in Chinese patients based on the histological types of testes.

Comparative sperm protein profiling in bulls differing in fertility and identification of phosphatidylethanolamine‐binding protein 4, a potential fertility marker

“…The reason for higher levels of fructose in seminal plasma of low fertile and infertile groups might be attributed to inefficiency or inability of spermatozoa to utilize free fructose in the seminal plasma (Lei et al, 2015). The ability of spermatozoa to utilize the free fructose is under the regulation of glycolytic enzymes and any deficiency or absence of these proteins/enzymes affect Figure 5 The sperm proteins from fertile, low fertile, and infertile were profiled using 2D gel electrophoresis.…”

Level of neutral alpha-1,4-glucosidase in seminal plasma of Chinese men

“…Epididymis is an important place for sperm capacitation before fertilisation, which plays a key role in sperm maturation and motility (Moore, ; Pena, Sanchez, Vasquez, Castillo, & Miska, ). NAG is exclusively generated in epididymis, which is regarded as a marker to evaluate the function of epididymis (Lei et al., ; Levrant et al., ). Said et al.…”

“…It was reported that the cut‐off value of NAG defined by World Health Organization () was not most sensitive and specific in Chinese patients (Lei et al., ). So, we supposed that NAG levels in different races from different country might be variable.…”

“…Neutral alpha‐1,4‐glucosidase (NAG) is exclusively generated in epididymis and has been regarded as a marker to evaluate the function of epididymis (Lei et al., ; Levrant, Watanabe, Land, Sauer, & Jeyendran, ). The epididymis also produces various molecules, such as l ‐carnitine and glycerophosphocholine, to be as functional epididymal markers (Cooper, Yeung, Nashan, & Nieschlag, ; Vivas‐Acevedo, Lozano‐Hernandez, & Camejo, ).…”

Technology Updates in Male Infertility Management

“…The role of fructose and neutral alpha glucosidase for discriminating obstructive and non obstructive azoospermia are well documented. 4,5 The methods for semen biochemical marker of seminal plasma have been develop from manual, semi-automatic, and fully automatic. The automatic method has several advantages such as simple reagent preparation, smaller amount reagents needed for each test, few errors, reduction manpower, simple calibration, and quality control procedure.…”