BACKGROUND: Exposure to the ionizing radiation (IR) encountered outside the magnetic field of the Earth poses a persistent threat to the reproductive functions of astronauts. The potential effects of space IR on the circadian rhythms of male reproductive functions have not been well characterized so far. METHODS: Here, we investigated the circadian effects of IR exposure (3 Gy X-rays) on reproductive functional markers in mouse testicular tissue and epididymis at regular intervals over a 24-h day. For each animal, epididymis was tested for sperm motility, and the testis tissue was used for daily sperm production (DSP), testosterone levels, and activities of testicular enzymes (glucose-6-phosphate dehydrogenase (G6PDH), sorbitol dehydrogenase (SDH), lactic dehydrogenase (LDH), and acid phosphatase (ACP)), and the clock genes mRNA expression such as Clock, Bmal1, Ror-α, Ror-β, or Ror-γ. RESULTS: Mice exposed to IR exhibited a disruption in circadian rhythms of reproductive markers, as indicated by decreased sperm motility, increased daily sperm production (DSP), and reduced activities of testis enzymes such as G6PDH, SDH, LDH, and ACP. Moreover, IR exposure also decreased mRNA expression of five clock genes (Clock, Bmal1, Ror-α, Ror-β, or Ror-γ) in testis, with alteration in the rhythm parameters. CONCLUSION These findings suggested potential health effects of IR exposure on reproductive functions of male astronauts, in terms of both the daily overall level as well as the circadian rhythmicity.
ARNTL Transcription Factors/genetics* ; Acid Phosphatase ; Animals ; CLOCK Proteins/genetics* ; Circadian Rhythm/radiation effects* ; Epididymis/radiation effects* ; Gene Expression/radiation effects* ; Genitalia, Male/radiation effects* ; Glucosephosphate Dehydrogenase ; L-Iditol 2-Dehydrogenase ; L-Lactate Dehydrogenase ; Male ; Mice ; Mice, Inbred C57BL ; Models, Animal ; Nuclear Receptor Subfamily 1, Group F, Member 1/genetics* ; Nuclear Receptor Subfamily 1, Group F, Member 2/genetics* ; Nuclear Receptor Subfamily 1, Group F, Member 3/genetics* ; RNA, Messenger/genetics* ; Radiation Exposure ; Radiation, Ionizing ; Reproductive Physiological Phenomena/radiation effects* ; Sperm Motility/radiation effects* ; Spermatozoa/radiation effects* ; Testis/radiation effects*

Objective: To investigate the improving effect of astaxanthin (AST) on the sperm quality of rats with ornidazole (ORN)-induced oligoasthenozoospermiaand its action mechanism. METHODS: Forty adult male SD rats were equally randomized into groups A (solvent control), B (low-dose ORN ［400 mg/（kg·d）］), C (high-dose ORN ［800 mg/（kg·d）］), D (low-dose ORN ［400 mg/（kg·d）］ + AST ［20 mg/（kg·d）］), and E (high-dose ORN ［800 mg/（kg·d）］ + AST ［20 mg/（kg·d）］), all treated intragastrically for3 weeks.After treatment, the epididymal tails ononeside was taken for determination of sperm concentration and activity, and the epididymideson the other side harvested for measurement of the activities of GSH-Px, GR, CAT and SOD and the MDA contentin the homogenate. RESULTS: Compared with group A, sperm motilityin the epididymal tail andGSH-Px and SOD activities in theepididymiswere markedly decreased while the MDAcontent significantlyincreased in group B (P<0.05), spermmotility and concentrationin the epididymal tail, testisindex, and the activities of GSH-Px, GR, CAT and SOD in the epididymis were remarkably reduced while theMDA contentsignificantly increased in group C(P<0.05). In comparison with group B, group D showed markedly increased sperm motility (［45.3±8.7］% vs ［66.3±8.9］%, P<0.05) in the epididymal tail and SOD activity in the epididymis (［116.7±25.3］ U/mg prot vs ［146.1±23.8］ U/mg prot, P<0.05), decreased MDA content(［1.68±0.45］ nmol/mg prot vs ［1.19±0.42］ nmol/mg prot, P<0.05).Compared with group C, group Eexhibited significant increases in the weight gained (［89.0±9.5］ vs ［99.9±4.1］ %, P<0.05) and sperm motility (［17.9±3.5］% vs ［27.3±5.3］ %, P<0.05) but a decrease in the content of MDA (［2.03±0.30］ nmol/mg prot vs ［1.52±0.41］ nmol/mg prot, P<0.05). CONCLUSIONS AST can improve spermquality in rats with ORN-inducedoligoasthenozoospermia, which may be associated with its enhancing effect on the antioxidant capacity of the epididymis.
Animals ; Antioxidants ; pharmacology ; Asthenozoospermia ; prevention & control ; Epididymis ; drug effects ; metabolism ; Male ; Oligospermia ; prevention & control ; Ornidazole ; Oxidative Stress ; Protective Agents ; pharmacology ; Radiation-Sensitizing Agents ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Sperm Count ; Sperm Motility ; Spermatozoa ; drug effects ; metabolism ; Xanthophylls ; pharmacology

OBJECTIVETo investigate the influences of mobile phone radiation on the quality and DNA methylation of human sperm in vitro.

METHODSAccording to the fifth edition of the WHO Laboratory Manual for the Examination and Processing of Human Semen, we randomly selected 97 male volunteers with normal semen parameters and divided each semen sample from the subjects into two equal parts, one exposed to mobile phone radiation at 1950 M Hz, SAR3. 0 W/kg for 3 hours while the other left untreated as the control. We obtained routine semen parameters as well as the acrosomal reaction ability, apoptosis and DNA methylation of sperm, and compared them between the two groups.

RESULTSCompared with the control, the radiation group showed significantly decreased progressive sperm motility ([36.64 ± 16.93] vs [27.56 ± 16.92]%, P < 0.01) and sperm viability ([63.72 ± 16.35] vs [54.31 ± 17.35]%, P < 0.01) and increased sperm head defects ([69.92 ± 4.46] vs [71.17 ± 4.89]%, P < 0.05), but no significant differences in sperm acrosomal reaction ([66.20 ± 6.75] vs [64.50 ± 3.47]%, P > 0.05). The early apoptosis rate of sperm cells was remarkably higher in the radiation group ([6.89 ± 9.84]%) than in the control ([4.44 ± 5.89]%) (P < 0.05). However, no statistically significant differences were found between the control and radiation groups in the DNA methylation patterns of the paternal imprinting gene H19 ICR ([0.60 ± 0.02] vs [1.40 ± 0.03]%, P > 0.05) or the maternal imprinting gene KvDMR1 ([0.00 ± 0.00] vs [1.80 ± 0.031%, P > 0.05).

CONCLUSIONMobile phone radiation reduces the progressive motility and viability of human sperm and increases sperm head defects and early apoptosis of sperm cells.

Cell Phone ; DNA Methylation ; radiation effects ; Humans ; In Vitro Techniques ; Male ; Semen ; radiation effects ; Semen Analysis ; Sperm Head ; radiation effects ; Sperm Motility ; radiation effects ; Spermatozoa ; cytology ; radiation effects

Animals ; Down-Regulation ; radiation effects ; Heavy Ion Radiotherapy ; adverse effects ; Infertility, Male ; etiology ; Male ; Mice ; Random Allocation ; Sperm Motility ; radiation effects ; Spermatozoa ; metabolism ; radiation effects ; Tubulin ; metabolism

OBJECTIVETo investigate the effect of simulated microgravity and carbon ion irradiation (CIR) on spermatogenic cell apoptosis and sperm DNA damage to the testis of male Swiss Webster mice, and assess the risk associated with space environment.

METHODSSperm DNA damage indicated by DNA fragmentation index (DFI) and high DNA stainability (HDS) was measured by sperm chromatin structure assay (SCSA). Apoptosis of spermatogenic cells was detected by annexin V-propidium iodide assay. Bax (the expression levels of p53) and proliferating cell nuclear antigen (PCNA) were measured by immunoblotting; p53 and PCNA were located by immunohistology.

RESULTSHDS, DFI, apoptosis index, and the expression levels of p53 and Bax were detected to be significantly higher in the experimental groups (P<0.05) compared with those in the control group; however, the PCNA expression varied to a certain degree. p53- and PCNA- positive expression were detected in each group, mainly in relation to the spermatogonic cells and spermatocytes.

CONCLUSIONThe findings of the present study demonstrated that simulated microgravity and CIR can induce spermatogenic cell apoptosis and sperm DNA damage. Sperm DNA damage may be one of the underlying mechanisms behind male fertility decline under space environment. These findings may provide a scientific basis for protecting astronauts and space traveler's health and safety.

Animals ; Apoptosis ; radiation effects ; Carbon ; Cell Proliferation ; radiation effects ; DNA Damage ; Heavy Ions ; adverse effects ; Immunohistochemistry ; Male ; Mice ; Random Allocation ; Sperm Count ; Spermatogenesis ; radiation effects ; Spermatozoa ; radiation effects ; Testis ; radiation effects ; Weightlessness Simulation

OBJECTIVETo determine whether laser-assisted immobilization of sperm damages sperm DNA.

METHODSTwenty-three semen samples were selected from an IVF program. Then normal spermatozoa were obtained by swimming-up method and immobilized with the tail by 0.45 ms pulse laser. Terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) and single cell gel electrophoresis (SCGE) were used to detect sperm DNA damage.

RESULTSThere was no significant difference either before and after laser treatment in the percentage of TUNEL-positive spermatozoa ([1.32 +/- 0.61]% vs [1.41 +/- 0.51]%, P > 0.05) or in SCGE ([1.59 +/- 0.70]% vs [1.83 +/- 0.68]%, P > 0.05).

CONCLUSIONLaser-assisted sperm immobilization may cause no direct damage to the sperm DNA.

Comet Assay ; DNA Damage ; radiation effects ; Humans ; In Situ Nick-End Labeling ; In Vitro Techniques ; Lasers ; Male ; Semen ; radiation effects ; Sperm Motility ; Spermatozoa

OBJECTIVETo explore the pathological characteristics and the dynamic change regularity of the testis induced by high power microwave (HPM) radiation.

METHODSOne hundred and sixty-five male Wistar rats were exposed to 0, 3, 10, 30 and 100 mW/cm2 HPM radiation for five minutes, and changes of testicular morphology and teratogenic ratio of epididymal spermatozoa were observed through light microscope and electron microscope at 6 h, 1, 3, 7, 14, 28 and 90 d after radiation.

RESULTSInjury of testicular spermatogenic cells in rats might be induced by 3 to approximately 100 mW/cm2 HPM radiation, and the main pathological changes were degeneration, necrosis, shedding of spermatogenic cells, formation of multinuclear giant cells, decrease or loss of sperm and interstitial edema. Injury of spermatogenic cells underwent such phases as death and shedding, cavitation, regeneration and repair, characterized by being focalized, inhomogenous and phased. And the severity of pathological changes of the testis increased with power density. There was only scattered degeneration, necrosis, shedding of spermatogenic cells in the seminiferous tubule one day after 3 mW/cm2 radiation, and the pathological changes six hours after 10 mW/cm2 radiation was similar to those one day after 3 mW/cm2 radiation, but with the formation of multinuclear giant cells, and the above-mentioned pathological changes aggravated from one day to seven days after radiation. There was a significant increase in degeneration, necrosis, shedding of spermatogenic cells, as well as a significant decrease in spermatozoa and focal necrosis in simple seminiferous tubules six hours after 30 and 100 mW/cm2 radiation, and the subsequent changes were similar to those of 10 mW/cm2 radiation. There was a significant increase in teratogenic ratio of epididymal spermatozoa at 3 d, 1 to approximately 7 d, 6 h to approximately 7 d after 3, 10, 30 and 100 mW/cm2 microwave radiation respectively (P < 0.01 or P < 0.05).

CONCLUSIONHPM radiation may cause injury of testicular spermatogenic cells in rats, which has a positive correlation to radiation dosage and time.

Animals ; Dose-Response Relationship, Radiation ; Male ; Microwaves ; Rats ; Rats, Wistar ; Spermatozoa ; pathology ; radiation effects ; Testis ; pathology ; radiation effects

OBJECTIVETo investigate the changes in the expressions of Bcl-2 protein and C-myc protein in the spermatogenic cells of rats after exposure to high power microwave (HPM) and to elucidate the possible mechanisms underlying the apoptosis induced by HPM at the genetic translation level.

METHODSOne hundred and twenty-five healthy male SD rats were divided randomly into unexposed control and experimental groups. The latter were radiated with S wave band 10 W/cm2, 20 W/cm2 HPM for 5 min and 10 min. Testicular samples were taken 6 h, 24 h, 48 h, 72 h and 120 h after radiation and studied respectively. Five blank radiation groups served as controls. Then immunohistochemical SP staining was performed to test the expressions of Bcl-2 protein and C-myc protein in the spermatogenic cells in the rats.

RESULTSThe expression of Bcl-2 protein in the 24 h group was up-regulated after radiated for 5 minutes and 10 minutes by HPM, higher in the 20 mW/cm2 group than in the 10 mW/cm2 group (P < 0.01). There was no expression of C-myc/Bcl-2 protein in the control group.

CONCLUSIONExposure to HPM for 24 h can up-regulate the expressions of C-myc protein and Bcl-2 protein in the spermatogenic cells of rats, which might be one of the mechanisms of the apoptosis induced by HPM.

Animals ; Apoptosis ; radiation effects ; Male ; Microwaves ; Proto-Oncogene Proteins c-bcl-2 ; biosynthesis ; Proto-Oncogene Proteins c-myc ; biosynthesis ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Spermatozoa ; metabolism ; Testis ; cytology ; metabolism ; radiation effects

OBJECTIVETo study the effects of 50 Hz electromagnetic fields (EMFs) on DNA of testicular cells and sperm chromatin structure in mice.

METHODSMice were exposed to 50 Hz, 0.2 mT or 6.4 mT electromagnetic fields for 4 weeks. DNA strand breakage in testicular cells was detected by single-cell gel electrophoresis assay. Sperm chromatin structure was analyzed by sperm chromatin structure assay with flow cytometry.

RESULTSAfter 50 Hz, 0.2 mT or 6.4 mT EMFs exposure, the percentage of cells with DNA migration in total testicular cells increased from the control level of 25.64% to 37.83% and 39.38% respectively. The relative length of comet tail and the percentage of DNA in comet tail respectively increased from the control levels of 13.06% +/- 12.38% and 1.52% +/- 3.25% to 17.86% +/- 14.60% and 2.32% +/- 4.26% after 0.2 mT exposure and to 17.88% +/- 13.71% and 2.35% +/- 3.87% after 6.4 mT exposure (P < 0.05). Exposure to EMFs had not induced significant changes in S.D.alphaT and XalphaT, but COMPalphaT (cells outside the main population of alpha t), the percentage of sperms with abnormal chromatin structure, increased in the two exposed groups.

CONCLUSION50 Hz EMFs may have the potential to induce DNA strand breakage in testicular cells and sperm chromatin condensation in mice.

Animals ; Chromatin ; radiation effects ; ultrastructure ; Comet Assay ; DNA ; analysis ; radiation effects ; DNA Damage ; Electromagnetic Fields ; Flow Cytometry ; Male ; Mice ; Mice, Inbred Strains ; Spermatozoa ; radiation effects ; ultrastructure ; Testis ; cytology ; radiation effects

OBJECTIVETo investigate the relationship between microwave radiation and male reproductivity.

METHODSAfter filling out questionnaire and body check, we carried out molecular epidemiological studies, using single cell gel electrophoresis (SCGE) and sperm automatic analysis among people working on radar.

RESULTSQuality of semen and semi-clinical injury of sperm among the people working on radar had changed when radar electromagnetic wave frequency distance, intensity, lasting time and protection shield were changing. Dose-response relationship was noticed and the increase of sperm dysmorphia played a principal role. The results between exposed group and control group showed significant difference (P < 0.01).

CONCLUSIONPeople working on radar who suffered from non-ionization for long time and had bad radar shield protection would show semi-clinical injury on sperm and bad semen quality. However, it did not affect the male reproductive function. It was necessary to reinforce the protection of non-ionization and to improve male reproductive health care of people working on radar.

Adult ; Comet Assay ; Cross-Sectional Studies ; Dose-Response Relationship, Radiation ; Fertility ; physiology ; radiation effects ; Humans ; Male ; Occupational Exposure ; analysis ; Radar ; Radiation, Nonionizing ; Spermatozoa ; cytology ; radiation effects ; Time Factors