Sperm quality and DNA damage in men from Jilin Province, China, who are occupationally exposed to ionizing radiation

Abstract

ABSTRACT. Long-term radiation exposure affects human health. Ionizing radiation has long been known to raise the risk of cancer. In addition to high doses of radiation, low-dose ionizing radiation might increase the risk of cardiovascular disease, lens opacity, and some other non-cancerous diseases. Low-and high-dose exposures to ionizing radiation elicit different signaling events at the molecular level, and may involve different response mechanisms. The health risks arising from exposure to low doses of ionizing radiation should be re-evaluated. Health workers exposed to ionizing radiation experience low-dose radiation and have an increased risk of hematological malignancies. Reproductive function is sensitive to changes in the physical environment, including ionizing radiation. However, data is scarce regarding the association between occupational radiation exposure and risk to human fertility. Sperm DNA integrity is a functional parameter of male fertility evaluation. Hence, we aimed to report sperm quality and DNA damage in men from Jilin Province, China, who were occupationally exposed to ionizing radiation. Sperm motility and normal morphology were significantly lower in the exposed compared with the non-exposed men. There was no statistically significant difference in sperm concentration between exposed and non-exposed men. The sperm DNA fragmentation index was significantly higher in the exposed than the non-exposed men. Chronic long-term exposure to low doses of ionizing radiation could affect sperm motility, normal morphology, and the sperm DNA fragmentation index in the Chinese population. Sperm quality and DNA integrity are functional parameters that could be used to evaluate occupational exposure to ionizing radiation.

Effect of ionizing radiation on the male reproductive system

“…Such a group is the staff of X-ray laboratories. Among males exposed to contact with radioactivity, a decrease was observed in sperm motility, an increase in the percentage of pathological sperm (the abnormalities concerned primarily the head), as well as an intensification of vacuolization [51,52]. In addition, examinations of the genetic material in the sperm of these males showed an intensification of fragmentation and total methylation of genomic DNA [51].…”

Taurine Protects Mouse Spermatocytes from Ionizing Radiation-Induced Damage Through Activation of Nrf2/HO-1 Signaling

“…The testis, as one of the most radiation sensitive organs, can be significantly impaired by even low doses of radiation [8]. The reported dysfunctions include sperm chromosome aberrations [9], motility decreased [10], swimming behavior impaired [11] and testis weights decreased [12]. Spermatogenesis is a complex process involving a wide series of cellular events, ranging from spermatogonia, spermatocytes, spermatids and spermatozoa [13, 14].…”

Low-dose radiation-induced risk in spermatogenesis

“…In 2013, a study of 83 occupationally exposed health workers clarified the effects in spermatozoa which showed changes in motility characteristics, increased sperm morphological abnormalities, sperm DNA fragmentation and global hyper methylation (Kumar et al 2013). A subsequent study also showed decreased sperm motility, abnormal morphology and significantly higher DNA fragmentation index in exposed compared to non-exposed men (Zhou et al 2016). These studies provide new insights into low-dose risks on human sperm characteristics but are limited by the small sample size in each case.…”