P–036 Investigation of the 2100 MHz electromagnetic field effects on sperm CatSper calcium channel

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
B Ayas ◽  
A Kocaman

Abstract Study question Does electromagnetic field (EMF) effect sperm motility through CatSper calcium channels in rat? Summary answer 2100 MHz EMF may reduce sperm motility by acting on CatSper calcium channels. What is known already EMF exposure has become a serious concern in infertility patients. The effects of EMF through by using mobile phone and laptop have been explored previously, mostly focusing on sperm motility and DNA fragmentation. EMF activates the voltage gated calcium channels and increases calcium concentration. As a result of the EMA exposure, the sperm motility may increase. However, if this happens while sperms are in non-progressive motile phase in the epididymis, it may result with the depletion of limited energy stores. Sperms may become immotile and they can’t move forward in the progressive motile phase in the female reproductive system. Study design, size, duration This basic research study was an in vivo experimental approach involving the use of 50 male rats. Wistar-Albino rats (n = 10) weighing ∼320 –350g were included in each groups. The duration of EMF exposure was 1 hour per day for 28 days. Amlodipine (1 mg/kg, 28 days) was used as a calcium channel blocker. The experiment was held between July to December in 2020. 20 female rats were recruited for mating test. Participants/materials, setting, methods 50 rats were divided into five groups. Group 1; Pure control. Group 2; Sham. Group 3; EMF exposure, Group 4: EMF+Amlodipine, Group 5: Amlodipine positive control. After four weeks of exposure, rats were sacrificed and sperm were collected from cauda epididymis. Sperm motility parameters were analyzed. Intracellular calcium levels were determined with two different method, fluorescence spectrophotometer and laser scanning confocal microscope. Before sacrifice, rats were mated with female rats to evaluate mating ratios. Main results and the role of chance The mating score and live birth rates did not vary significantly among the groups (p > 0.05). The sperm motility (A+B, 47.62±16.92 versus 34.19±14.62) and intracellular calcium levels (2.46±0.20 versus 1.85±0.18) were significantly decreased in the EMF group (p < 0.05). The results of fluorescence spectrophotometer and laser scanning confocal microscopy with fluorescent attachment were consistent with each other. There were no significant differences found among the other groups in terms of investigated parameters. Statistical analysis was performed with Kruskal-Wallis test followed by the Dunn-Bonferroni’s test. Limitations, reasons for caution The Catsper 1, 2, 3, 4 gene expression levels are still under analyses. These gene expression levels will be helpful to understand possible changes of the sperm motility. The determination of other motility related gene expressions may strength the results. Wider implications of the findings: EMF exposure may have a significant effect on sperm motility parameters. Mobile phones carried very close to the reproductive organs may adversely affect the motility of sperm cells due to its emitted radiation levels Trial registration number Not applicable

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
A Kocaman ◽  
B Ayas

Abstract Study question Does kisspeptin administration affect the motility parameters in sperm samples of subfertile cases? Summary answer Kisspeptin administration significantly increased gene expression levels related with sperm motility as well as intracellular calcium concentrations. What is known already Sperm motility problems are among the most important causes of male infertility. In recent years, a peptide named kisspeptin has been discovered that may have effects on sperm motility. Kisspeptin is known to trigger calcium release in hypothalamic neurons. In addition, kisspeptin administration increased sperm progressive motility in studies conducted on normozoospermic individuals. Furthermore, it is suggested that kisspeptin protein in seminal plasma is positively associated with semen quality. However, there is no evidence that how kisspeptin can affect sperm in men with infertility problems. Study design, size, duration This basic research study was an in vitro experimental approach involving the use of semen samples from an infertil cases between September to December in 2020. 40 men were included in both control and experimental groups. Participants/materials, setting, methods All analyses were performed on semen samples from 10 normozoospermic (NZ), 10 asthenozoospermic (AZ), 10 oligoasthenozoospermic (OAZ) and 10 oligoastenoteratozoospermic (OATZ) men, aging between (21-40) years. Basal serum and seminal kisspeptin levels were analyzed by ELISA. Sperm were divided into two groups. Kisspeptin-13 administered in vitro. KISS1, KISS1R, CATSPER1, AKAP4 gene expressions analyzed by qRT-PCR using 2−ΔΔCt algorithm. Intracellular calcium concentration was determined with floresence spectroflurometer and laser scanning confocal microscope. Main results and the role of chance The serum kisspeptin level of NZ was significantly higher than other groups (p < 0.05). The semen kisspeptin level was significantly higher than OAZ and OATZ (p < 0.05), but not in NZ (p > 0.05). Also, KISS1 gene expression was higher in AZ compared to other groups (p < 0.05). Biochemical and gene expression analysis of kisspeptin were consistent with each other. There was a significant increase in the expression of CATSPER1 gene in AZ compared to other groups (p < 0.05). Also, AKAP4 gene expression was significantly higher in OATZ compared to other groups (p < 0.05). No significant difference was documented for the expression of KISS1R (p > 0.05). Intracellular calcium was significantly increased in AZ and NZ after kisspeptin administration. The intracellular calcium increase is consistent with increased CATSPER1 gene expression levels in AZ. Kisspeptin administration may have a significant effect on sperm motility parameters. Limitations, reasons for caution The biochemical and gene expression levels of KISS1 were consistent. However, gene expression was explored at the mRNA level for CATSPER1 and AKAP4. The protein expression analyses of these genes may confirm the results. Also, using kisspeptin antagonists may strength the results of intracellular calcium analysis. Wider implications of the findings Kisspeptin treatment for individuals diagnosed with asthenozoospermia may have therapeutic results. KISS1 quantitation may be a determining factor for the subfertility in routine semen analysis. Trial registration number OMU KAEK 2019/462


Author(s):  
Chris A Glasbey ◽  
Thorsten Forster ◽  
Peter Ghazal

Digital images obtained by the laser scanning of spotted microarrays often include saturated pixel values. These arise when the scan settings are sufficiently high and some pixels exceed the limit L=65535 and are instead set to L. Failure to adjust for this censoring leads to biased estimates of gene expression levels. To impute censored values, we propose a linear model based on the principal components of uncensored spots on the same array. This is computationally fast, flexible to adapt to distinctive spot shapes and profiles on different arrays, and is shown to be more effective than the polynomial-hyperbolic model in correcting for the bias. The application to biological data demonstrates the potential for enhancing the dynamic range of detection. Fortran90 subroutines implementing these methods are available at http://www.bioss.ac.uk/~chris.


2016 ◽  
Vol 28 (4) ◽  
pp. 434 ◽  
Author(s):  
Mariana Rios ◽  
Daniela V. Carreño ◽  
Carolina Oses ◽  
Nelson Barrera ◽  
Bredford Kerr ◽  
...  

Prostaglandins (PGs) have been reported to be present in the seminal fluid and cervical mucus, affecting different stages of sperm maturation from spermatogenesis to the acrosome reaction. This study assessed the effects of low physiological PGE2 and PGF2α concentrations on human sperm motility and on the ability of the spermatozoa to bind to the zona pellucida (ZP). Human spermatozoa were isolated from seminal samples with normal concentration and motility parameters and incubated with 1 μM PGE2, 1 μM PGF2α or control solution to determine sperm motility and the ability to bind to human ZP. The effects of both PGs on intracellular calcium levels were determined. Incubation for 2 or 18 h with PGE2 or PGF2α resulted in a significant (P < 0.05) increase in the percentage of spermatozoa with progressive motility. In contrast with PGF2α, PGE2 alone induced an increase in sperm intracellular calcium levels; however, the percentage of sperm bound to the human ZP was doubled for both PGs. These results indicate that incubation of human spermatozoa with low physiological levels of PGE2 or PGF2α increases sperm functions and could improve conditions for assisted reproduction protocols.


1991 ◽  
Vol 71 (3) ◽  
pp. 1062-1069 ◽  
Author(s):  
M. Shirahata ◽  
R. S. Fitzgerald

The hypothesis that the entry of extracellular calcium ions into some compartment, quite possibly the type I cells, through voltage-gated calcium channels (VGCC) is essential for hypoxic chemotransduction in the cat carotid body was tested using an in situ perfusion technique. The neural output of the carotid body of anesthetized, paralyzed, and artificially ventilated cats in response to perfusions with Krebs-Ringer bicarbonate solution (KRB), calcium-free KRB, KRB containing calcium channel blockers, or KRB containing BAY K 8644 was recorded. Selective perfusion of the carotid body with hypoxic calcium-free KRB significantly decreased carotid chemoreceptor activity, suggesting that extracellular calcium is essential for hypoxic chemotransduction. Selective perfusion of the carotid body with hypoxic KRB containing verapamil (10–100 microM), diltiazem (10–100 microM), or nifedipine (10–100 microM) dose dependently attenuated the increase in chemoreceptor activity produced by hypoxia, suggesting that VGCC need to be activated for hypoxic chemotransduction. The carotid body response to hyperoxic KRB containing the calcium channel agonist BAY K 8644 (10 microM) was 267 +/- 87% of hyperoxic control KRB, suggesting that an enhanced influx of calcium ions through VGCC stimulates carotid chemoreceptor activity. Selective perfusion of the carotid body with severely hypoxic KRB containing BAY K 8644 did not increase chemoreceptor activity above that produced by severe hypoxia alone. This suggests that severe hypoxia increases intracellular calcium in some compartment of the carotid body to achieve stimulatory maximum response and that further increase in intracellular calcium does not produce further elevation of neural activity.(ABSTRACT TRUNCATED AT 250 WORDS)


2003 ◽  
Vol 178 (3) ◽  
pp. 381-393 ◽  
Author(s):  
RD Jones ◽  
LN Ruban ◽  
IE Morton ◽  
SA Roberts ◽  
KM English ◽  
...  

Testosterone-induced vasodilatation is proposed to contribute to the beneficial effects associated with testosterone replacement therapy in men with cardiovascular disease, and is postulated to occur via either direct calcium channel blockade, or through potassium channel activation via increased production of cyclic nucleotides. We utilised flow cytometry to investigate whether testosterone inhibits the increase in cellular fluorescence induced by prostaglandin F(2alpha) in A7r5 smooth muscle cells loaded with the calcium fluorescent probe indo-1-AM, and to study the cellular mechanisms involved. Two-minute incubation with testosterone (1 microM) significantly inhibited the change in cellular fluorescence in response to prostaglandin F(2alpha) (10 microM) (3.6+/-0.6 vs 7.6+/-1.0 arbitrary units, P=0.001). The change in cellular fluorescence in response to prostaglandin F(2alpha) (10 microM) was also significantly attenuated in the absence of extracellular calcium (3.6+/-0.3 vs 15.6+/-0.7 arbitrary units, P=0.0000002), and by a 2-min incubation with the store-operated calcium channel blocker SK&F 96365 (50 microM) (4.7+/-0.8 vs 8.1+/-0.4 arbitrary units, P=0.003). The response was insensitive to similar incubation with the voltage-operated calcium channel blockers verapamil (10 microM) (12.6+/-1.2 vs 11.9+/-0.2 arbitrary units, P=0.7) or nifedipine (10 microM) (13.9+/-1.3 vs 13.3+/-0.5 arbitrary units, P=0.7). Forskolin (1 microM) and sodium nitroprusside (100 microM) significantly increased the cellular concentration of cyclic adenosine monophosphate and cyclic guanosine monophosphate respectively, but testosterone (100 nM-100 microM) had no effect. These data indicate that the increase in intracellular calcium in response to prostaglandin F(2alpha) occurs primarily via extracellular calcium entry through store-operated calcium channels. Testosterone inhibits the response, suggesting an antagonistic action upon these channels.


2014 ◽  
Vol 23 (03) ◽  
pp. 207-211
Author(s):  
C. Kasch ◽  
A. Osterberg ◽  
Thordis Granitzka ◽  
T. Lindner ◽  
M. Haenle ◽  
...  

SummaryThe RANK/RANKL/OPG system plays an important role in the regulation of bone metabolism and bony integration around implants. The aim of this study was to analyse gene expression of OPG, RANK, and RANKL in regenerating bone during implant integration. Additionally, the effect of intermittent para - thyroid hormone (PTH) treatment was analysed. A titanium chamber was implanted in the proximal tibiae of 48 female rats. The animals received either human PTH or saline solution (NaCl). After 21 and 42 days, RNA was isolated from tissue adjacent to the implant and expression of RANK, RANKL, and OPG was analysed. After 21 days, very low expression levels of all genes were shown. In contrast, increased gene expression after 42 days was determined. Expression of RANK and RANKL was lower than that for OPG. The lower expression levels after 21 days might be due to still ossifying, fibrotic tissue around the titanium chamber. An increased OPG synthesis rate associated with decreased RANKL expression after 42 days revealed bone-forming processes. Despite significant differences in gene expression between the time points, only slight differences were observed between application of intermittent PTH and NaCl after a period of 42 days.


2021 ◽  
Author(s):  
Pavel V. Mazin ◽  
Philipp Khaitovich ◽  
Margarida Cardoso-Moreira ◽  
Henrik Kaessmann

AbstractAlternative splicing (AS) is pervasive in mammalian genomes, yet cross-species comparisons have been largely restricted to adult tissues and the functionality of most AS events remains unclear. We assessed AS patterns across pre- and postnatal development of seven organs in six mammals and a bird. Our analyses revealed that developmentally dynamic AS events, which are especially prevalent in the brain, are substantially more conserved than nondynamic ones. Cassette exons with increasing inclusion frequencies during development show the strongest signals of conserved and regulated AS. Newly emerged cassette exons are typically incorporated late in testis development, but those retained during evolution are predominantly brain specific. Our work suggests that an intricate interplay of programs controlling gene expression levels and AS is fundamental to organ development, especially for the brain and heart. In these regulatory networks, AS affords substantial functional diversification of genes through the generation of tissue- and time-specific isoforms from broadly expressed genes.


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