Intracellular nitric oxide measurement in human sperm using 4, 5-diaminofluorescein-2-diacetate and flow cytometry

2011 ◽  
Vol 96 (3) ◽  
pp. S232-S233
Author(s):  
R. Sharma ◽  
S. Bani Hani ◽  
M. Bayachou ◽  
E. Sabanegh ◽  
A. Agarwal
2020 ◽  
Vol 22 (1) ◽  
pp. 93
Author(s):  
Arturo Matamoros-Volante ◽  
Valeria Castillo-Viveros ◽  
Paulina Torres-Rodríguez ◽  
Marcela B. Treviño ◽  
Claudia L. Treviño

Plasma membrane (PM) hyperpolarization, increased intracellular pH (pHi), and changes in intracellular calcium concentration ([Ca2+]i) are physiological events that occur during human sperm capacitation. These parameters are potential predictors of successful outcomes for men undergoing artificial reproduction techniques (ARTs), but methods currently available for their determination pose various technical challenges and limitations. Here, we developed a novel strategy employing time-lapse flow cytometry (TLFC) to determine capacitation-related membrane potential (Em) and pHi changes, and progesterone-induced [Ca2+]i increases. Our results show that TLFC is a robust method to measure absolute Em and pHi values and to qualitatively evaluate [Ca2+]i changes. To support the usefulness of our methodology, we used sperm from two types of normozoospermic donors: known paternity (subjects with self-reported paternity) and no-known paternity (subjects without self-reported paternity and no known fertility problems). We found relevant differences between them. The incidences of membrane hyperpolarization, pHi alkalinization, and increased [Ca2+]i were consistently high among known paternity samples (100%, 100%, and 86%, respectively), while they varied widely among no-known paternity samples (44%, 17%, and 45%, respectively). Our results indicate that TLFC is a powerful tool to analyze key physiological parameters of human sperm, which pending clinical validation, could potentially be employed as fertility predictors.


2001 ◽  
Vol 280 (1) ◽  
pp. H344-H353 ◽  
Author(s):  
Mohammad N. Sharikabad ◽  
Kirsten M. Østbye ◽  
Torstein Lyberg ◽  
Odd Brørs

The effects of Mg2+ on reactive oxygen species (ROS) and cell Ca2+ during reoxygenation of hypoxic rat cardiomyocytes were studied. Oxidation of 2′,7′-dichlorodihydrofluorescein (DCDHF) to dichlorofluorescein (DCF) and of dihydroethidium (DHE) to ethidium (ETH) within cells were used as markers for intracellular ROS levels and were determined by flow cytometry. DCDHF/DCF is sensitive to H2O2 and nitric oxide (NO), and DHE/ETH is sensitive to the superoxide anion (O2 −·), respectively. Rapidly exchangeable cell Ca2+ was determined by 45Ca2+uptake. Cells were exposed to hypoxia for 1 h and reoxygenation for 2 h. ROS levels, determined as DCF fluorescence, were increased 100–130% during reoxygenation alone and further increased 60% by increasing extracellular Mg2+concentration to 5 mM at reoxygenation. ROS levels, measured as ETH fluorescence, were increased 16–24% during reoxygenation but were not affected by Mg2+. Cell Ca2+ increased three- to fourfold during reoxygenation. This increase was reduced 40% by 5 mM Mg2+, 57% by 10 μM 3,4-dichlorobenzamil (DCB) (inhibitor of Na+/Ca2+ exchange), and 75% by combining Mg2+ and DCB. H2O2 (25 and 500 μM) reduced Ca2+ accumulation by 38 and 43%, respectively, whereas the NO donor S-nitroso- N-acetyl-penicillamine (1 mM) had no effect. Mg2+ reduced hypoxia/reoxygenation-induced lactate dehydrogenase (LDH) release by 90%. In conclusion, elevation of extracellular Mg2+ to 5 mM increased the fluorescence of the H2O2/NO-sensitive probe DCF without increasing that of the O2 −·-sensitive probe ETH, reduced Ca2+ accumulation, and decreased LDH release during reoxygenation of hypoxic cardiomyocytes. The reduction in LDH release, reflecting the protective effect of Mg2+, may be linked to the effect of Mg2+ on Ca2+ accumulation and/or ROS levels.


2009 ◽  
Vol 46 (10) ◽  
pp. 1420-1427 ◽  
Author(s):  
Eve de Lamirande ◽  
Geneviève Lamothe ◽  
Michèle Villemure

Circulation ◽  
2018 ◽  
Vol 138 (Suppl_1) ◽  
Author(s):  
Angela Kosta ◽  
Sergey V Ryzhov ◽  
Robert S Kramer ◽  
Reed D Quinn ◽  
Douglas Sawyer ◽  
...  

Introduction: Dysregulation of endothelial nitric oxide synthase (eNOS) and generation of nitric oxide (NO) are critical early indicators for diabetes-induced endothelial dysfunction and cardiovascular complications. We hypothesize that levels of NO production and eNOS expression by endothelial cells are decreased in DM subjects when compared to non-DM subjects. Methods: The study cohort consisted of 9 non-DM subjects and 6 DM subjects undergoing myocardial biopsy at the time of coronary artery bypass grafting surgery. The non-myocyte cell suspensions from the left ventricle (LV), right atrial appendages (RAA), and skeletal muscle (SKM) tissue were analyzed by flow cytometry to measure production of nitric oxide in subpopulations of endothelial and non-endothelial cells. Cells in suspension were incubated with DAF-2DA in the presence or absence of NO synthase inhibitor, L-NAME. Flow cytometry was used to determine production of NO in subpopulations of endothelial and non-endothelial cells from biopsies. Measurements of eNOS and phospho-eNOS (ser1177) were performed using western blot. Results: Basal Nitric oxide production was measurable in non-diabetic subjects \ in 55%, 80% and 65% of unstimulated endothelial cells obtained from RAA, LV and SKM biopsies, compared to 40%, 40%, and 66%, respectively in diabetic subjects ( P < 0.02, DM vs Non-DM). No differences were found in the number of NO-producing non-endothelial cells between DM and non-DM subjects. The level of eNOS showed a trend towards decreased protein expression in DM subjects compared to non-DM. Conclusions: Generation of NO by endothelial cells and level of eNOS expression are decreased in left ventricular endothelial cells of DM patients compared to non-DM. Left ventricular biopsies can be used safely for assessment of NO dysregulation and endothelial dysfunction, and whether these can be improved with interventions targeting diabetic cardiovascular disease.


2009 ◽  
Vol 91 (4) ◽  
pp. 1285-1292 ◽  
Author(s):  
Christiaan F. Hoogendijk ◽  
Theunis F. Kruger ◽  
Patric J.D. Bouic ◽  
Ralf R. Henkel

Reproduction ◽  
2011 ◽  
Vol 141 (1) ◽  
pp. 47-54 ◽  
Author(s):  
Erica Miraglia ◽  
Federico De Angelis ◽  
Elena Gazzano ◽  
Hossain Hassanpour ◽  
Angela Bertagna ◽  
...  

Nitric oxide (NO), a modulator of several physiological processes, is involved in different human sperm functions. We have investigated whether NO may stimulate the motility of human spermatozoa via activation of the soluble guanylate cyclase (sGC)/cGMP pathway. Sperm samples obtained by masturbation from 70 normozoospermic patients were processed by the swim-up technique. The kinetic parameters of the motile sperm-rich fractions were assessed by computer-assisted sperm analysis. After a 30–90 min incubation, the NO donor S-nitrosoglutathione (GSNO) exerted a significant enhancing effect on progressive motility (77, 78, and 78% vs 66, 65, and 62% of the control at the corresponding time), straight linear velocity (44, 49, and 48 μm/s vs 34, 35, and 35.5 μm/s), curvilinear velocity (81, 83, and 84 μm/s vs 68 μm/s), and average path velocity (52, 57, and 54 μm/s vs 40, 42, and 42 μm/s) at 5 μM but not at lower concentrations, and in parallel increased the synthesis of cGMP. A similar effect was obtained with the NO donor spermine NONOate after 30 and 60 min. The GSNO-induced effects on sperm motility were abolished by 1H-[1,2,4]oxadiazolo-[4,3-a]quinoxalin-1-one (a specific sGC inhibitor) and mimicked by 8-bromo-cGMP (8-Br-cGMP; a cell-permeating cGMP analog); the treatment with Rp-8-Br-cGMPS (an inhibitor of cGMP-dependent protein kinases) prevented both the GSNO- and the 8-Br-cGMP-induced responses. On the contrary, we did not observe any effect of the cGMP/PRKG1 (PKG) pathway modulators on the onset of hyperactivated sperm motility. Our results suggest that NO stimulates human sperm motility via the activation of sGC, the subsequent synthesis of cGMP, and the activation of cGMP-dependent protein kinases.


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