Reactive oxygen species measurement in neat and washed semen: comparative analysis and its significance in male infertility assessment

Abstract

Measurement of ROS in neat semen reflects the original oxidative status in the actual sperm microenvironment and is an easy, simple, inexpensive and rapid method compared with ROS measurement from washed semen. ROS measurement in washed semen is done to assess ROS levels following sperm processing as in cases opting for assisted conception. As both ROS values in neat and washed show a positive correlation, neat semen may be used as a valuable tool for identifying infertile men with seminal OS. ROS levels are elevated in nearly 70% men with idiopathic infertility. Hence, ROS analysis in neat semen has both good diagnostic and prognostic value in male infertility assessment.

Correlating Sperm Reactive Oxygen Species Production and Its Morphological Defects – Which Can Be the Best Possible Morphological Predictor of Oxidative Damage in Routine Screening?

“…23 out of the 36 cases and 6 out of 40 controls had ROS levels more than the critical value (d"22 RLU/sec/million spermatozoa). One of the previous studies in our laboratory [25] had established interquartile range of ROS levels in fertile controls as 0.014 -0.11 x 10, 000 RLU/min/ 20 million sperm (22 RLU/sec/ million spermatozoa) which is similar to the findings by Fingerova et al, [26] 0.12-0.55 x 1000 RLU/min/20 million sperm. It has also been observed that the % DNA fragmentation index (DFI) was significantly higher (32.88 ± 7.41) in infertile men with elevated ROS levels compared with controls (22.50 ± 2.81) with normal ROS levels [27].…”

The Blood-Testis Barrier and Its Implications for Male Contraception

“…For instance, cadmium is known to activate TGF-␤2 and -␤3 and p-p38 MAPK in the testis before extensive cellular damage can be detected in the seminiferous epithelium (Wong et al, 2004). In fact, an increase in oxidative stress was seen in ϳ80% of clinically proven infertile men who had long-term exposure to environmental toxicants (e.g., cadmium, smoking), which are emerging as a major contributing factor in male infertility (Kiziler et al, 2007;Tremellen, 2008;Venkatesh et al, 2011). In addition, recent studies have shown that flavonoids (antioxidants, such as genistein, myricetin, and quercetin) can protect the intestinal TJ barrier function from oxidative stress-induced barrier disruption caused by inflammatory cytokines, enteric bacteria, and chemicals (e.g., acetaldehyde) (Suzuki and Hara, 2011), illustrating the damaging effects of oxidative stress on TJ barrier function.…”

Sperm DNA integrity assays: diagnostic and prognostic challenges and implications in management of infertility

“…Since these sperm do not have the complete disulphide cross linking and even the epigenetic programming is incomplete this increases the risk of genetic and epigenetic defects in children conceived through these techniques [61]. Also these techniques require sperm preparation and processing in which the seminal plasma is removed by centrifugation and washing which makes sperm more vulnerable to oxidative damage [32].…”

“…Sperm DNA fragmentation may result from aberrant chromatin packaging during spermatogenesis [22,29,30], defective apoptosis [31] excessive reactive oxygen species (ROS) production [12,22,29,30,[32][33][34][35] decreased seminal antioxidants [26]. External factors such as drugs, pollution, cigarette smoking, fever, xenobiotics, high testicular temperature, varicocele, and advanced age have also been associated with increased sperm DNA damage [36][37][38][39][40].…”