Inhibition of glycolysis in boar spermatozoa by alpha-chlorohydrin phosphate appears to be mediated by phosphatase activity

1995 ◽  
Vol 7 (5) ◽  
pp. 1089 ◽  
Author(s):  
AR Jones ◽  
LM Porter
Keyword(s):  
Phosphatase Activity ◽  
Triosephosphate Isomerase ◽  
Specific Inhibitor ◽  
Glycolytic Activity ◽  
Boar Sperm ◽  
Inhibition Of Glycolysis ◽  
Boar Spermatozoa

(R,S)-alpha-chlorohydrin-1-phosphate, previously shown to have no anti-glycolytic activity on mature boar sperm in vitro, is a substrate for acid and/or neutral phosphatase(s) that are associated with washed sperm. The high phosphatase activity hydrolyses the ester to alpha-chlorohydrin which undergoes oxidation to (S)-3-chlorolactaldehyde, a specific inhibitor of sperm glyceraldehyde-3-phosphate dehydrogenase and triosephosphate isomerase, thereby exhibiting an anti-glycolytic action.

Oxidative metabolic activity of boar spermatozoa: a system for assessing anti-glycolytic activity of potential inhibitors in vitro

1989 ◽  
Vol 1 (4) ◽  
pp. 357 ◽  
Author(s):  
AR Jones ◽  
LA Chantrill
Keyword(s):  
Metabolic Activity ◽  
Oxidative Metabolism ◽  
Model System ◽  
High Rate ◽  
Chemical Agents ◽  
Glycolytic Activity ◽  
Metabolic Capability ◽  
Potential Inhibitors ◽  
Boar Spermatozoa

The oxidative metabolic capability of mature boar spermatozoa has been determined in vitro. The high rate of oxidation of fructose, glucose, glycerol, glycerol-3-phosphate and lactate to CO2 and the optimization of incubation conditions indicates that these cells could constitute a model system for investigating the anti-glycolytic activity of potential male anti-fertility agents. The effects of several chemical agents on the oxidative metabolism of boar spermatozoa are reported.

Metabolic activity of hypotonically treated mature boar spermatozoa

1997 ◽  
Vol 9 (6) ◽  
pp. 583 ◽  
Author(s):  
A. R. Jones
Keyword(s):  
Oxygen Uptake ◽  
Metabolic Activity ◽  
Phosphate Buffer ◽  
Cytoplasmic Membrane ◽  
Mitochondrial Activity ◽  
Glycolytic Activity ◽  
Boar Sperm ◽  
Uptake Studies ◽  
Boar Spermatozoa

Treatment of washed boar sperm with hypotonic phosphate buffer removed the acrosome, disrupted the cytoplasmic membrane and almost completely separated the heads from the mid piece-tail segment. As assessed by oxygen uptake studies and their ability to oxidize14C-labelled substrates to 14CO2, hypotonically-treated cells exhibit low glycolytic activity yet mitochondrial activity remains high. Both lactate and glycerol 3-phosphate underwent oxidation and these substrates continued to be metabolized by this preparation which had been stored for up to 10 days at 4°C. Such preparations may be of assistance in the investigation of the biochemistry of boar sperm mitochondria.

Oligomycin A-induced inhibition of mitochondrial ATP-synthase activity suppresses boar sperm motility and in vitro capacitation achievement without modifying overall sperm energy levels

2014 ◽  
Vol 26 (6) ◽  
pp. 883 ◽  
Author(s):  
Laura Ramió-Lluch ◽  
Marc Yeste ◽  
Josep M. Fernández-Novell ◽  
Efrén Estrada ◽  
Luiz Rocha ◽  
...  
Keyword(s):  
Atp Synthase ◽  
Energy Levels ◽  
Specific Inhibitor ◽  
O2 Consumption ◽  
Atp Levels ◽  
Mitochondrial Atp Synthase ◽  
Oligomycin A ◽  
Boar Sperm ◽  
Induced Changes

Incubation of boar spermatozoa in a capacitation medium with oligomycin A, a specific inhibitor of the F0 component of the mitochondrial ATP synthase, induced an immediate and almost complete immobilisation of cells. Oligomycin A also inhibited the ability of spermatozoa to achieve feasible in vitro capacitation (IVC), as measured through IVC-compatible changes in motility patterns, tyrosine phosphorylation levels of the acrosomal p32 protein, membrane fluidity and the ability of spermatozoa to achieve subsequent, progesterone-induced in vitro acrosome exocytosis (IVAE). Both inhibitory effects were caused without changes in the rhythm of O2 consumption, intracellular ATP levels or mitochondrial membrane potential (MMP). IVAE was accompanied by a fast and intense peak in O2 consumption and ATP levels in control spermatozoa. Oligomycin A also inhibited progesterone-induced IVAE as well as the concomitant peaks of O2 consumption and ATP levels. The effect of oligomycin on IVAE was also accompanied by concomitant alterations in the IVAE-induced changes on intracellular Ca2+ levels and MMP. Our results suggest that the oligomycin A-sensitive mitochondrial ATP-synthase activity is instrumental in the achievement of an adequate boar sperm motion pattern, IVC and IVAE. However, this effect seems not to be linked to changes in the overall maintenance of adequate energy levels in stages other than IVAE.

scholarly journals Molecular Mechanisms Involved in the Impairment of Boar Sperm Motility by Peroxynitrite-Induced Nitrosative Stress

2020 ◽  
Vol 21 (4) ◽  
pp. 1208 ◽  
Author(s):  
Rebeca Serrano ◽  
Nicolás Garrido ◽  
Jose A. Céspedes ◽  
Lauro González-Fernández ◽  
Luis J. García-Marín ◽  
...  
Keyword(s):  
Sperm Motility ◽  
Molecular Mechanisms ◽  
Nitrosative Stress ◽  
Mitochondrial Activity ◽  
Dependent Protein Kinase ◽  
Plasma Membrane Fluidity ◽  
Boar Sperm ◽  
Dependent Protein ◽  
Boar Spermatozoa

Excessive levels of reactive nitrogen species (RNS) produce nitrosative stress. Among RNS is peroxynitrite, a highly reactive free radical generated when nitric oxide reacts with superoxide anion. Peroxynitrite effects have been mainly studied in somatic cells, and in spermatozoa the majority of studies are focused in humans. The aim of this study is to investigate the in vitro peroxynitrite effect on boar spermatozoa functions and the molecular mechanisms involved. Spermatozoa were exposed to the donor 3-morpholinosydnonimine (SIN-1) in non-capacitating or capacitating medium, motility was evaluated by CASA, functional parameters by flow cytometry and sperm protein phosphorylation by Western blotting. SIN-1 treatment, that significantly increases peroxynitrite levels in boar spermatozoa, potentiates the capacitating-stimulated phosphorylation of cAMP-dependent protein kinase 1 (PKA) substrates and GSK-3α. SIN-1 induced peroxynitrite does not decrease sperm viability, but significantly reduces sperm motility, progressive motility, velocities and motility coefficients. Concomitantly, peroxynitrite does not affect mitochondrial membrane potential, plasma membrane fluidity, or A23187-induced acrosome reaction. However, peroxynitrite significantly increases sperm lipid peroxidation in both media. In conclusion, peroxynitrite compromises boar sperm motility without affecting mitochondrial activity. Although peroxynitrite potentiates the phosphorylation of pathways leading to sperm motility, it also causes oxidative stress that might explain, at least partially, the motility impairment.

The anti-glycolytic activity of 3-bromopyruvate on mature boar spermatozoa in vitro

Contraception ◽  
1995 ◽  
Vol 52 (5) ◽  
pp. 317-320 ◽  
Author(s):  
A.R. Jones ◽  
L. Gillan ◽  
D. Milmlow
Keyword(s):  
Glycolytic Activity ◽  
Boar Spermatozoa

Control of glycolysis in mature boar spermatozoa: effect of pH in vitro

2004 ◽  
Vol 16 (3) ◽  
pp. 319 ◽  
Author(s):  
A. R. Jones ◽  
D. E. Connor
Keyword(s):  
Glycolytic Pathway ◽  
Cytoplasmic Ph ◽  
Effect Of Ph ◽  
Boar Sperm ◽  
Boar Spermatozoa

The glycolytic pathway in boar sperm is sensitive to pH, which decreases as lactate is produced from either glucose or fructose in vitro. The build up of lactate appears to be due to the saturation of mitochondrial lactate transporters, which causes the cytoplasmic pH to fall. Phosphofructokinase has been shown to be sensitive to this drop in pH rather than to the build up of lactate ions or ATP, thereby controlling the rate of glycolysis in vitro.

scholarly journals Importance of beta-lactamase inhibitor pharmacokinetics in the pharmacodynamics of inhibitor-drug combinations: studies with piperacillin-tazobactam and piperacillin-sulbactam.

1997 ◽  
Vol 41 (4) ◽  
pp. 721-727 ◽  
Author(s):  
P D Lister ◽  
A M Prevan ◽  
C C Sanders
Keyword(s):  
Antibacterial Activity ◽  
Critical Concentration ◽  
Specific Inhibitor ◽  
Logarithmic Phase ◽  
Critical Ratio ◽  
Beta Lactamase ◽  
Beta Lactam ◽  
Dosing Regimens ◽  
Lactamase Inhibitor

An in vitro pharmacokinetic model was used to study the pharmacodynamics of piperacillin-tazobactam and piperacillin-sulbactam against gram-negative bacilli producing plasmid-encoded beta-lactamases. Logarithmic-phase cultures were exposed to peak antibiotic concentrations observed in human serum after the administration of intravenous doses of 3 g of piperacillin and 0.375 g of tazobactam or 0.5 g of sulbactam. Piperacillin and inhibitor were either dosed simultaneously or piperacillin was dosed sequentially 0.5 h after dosing with the inhibitor. In studies with all four test strains, the pharmacodynamics observed after simultaneous dosing were similar to those observed with the sequential regimen. Since the ratio between piperacillin and tazobactam was in constant fluctuation after sequential dosing, these data suggest that the pharmacodynamics of the piperacillin-inhibitor combinations were not dependent upon maintenance of a critical ratio between the components. Furthermore, when regrowth was observed, the time at which bacterial counts began to increase was similar between the simultaneous and sequential dosing regimens. Since the pharmacokinetics of the inhibitors were the same for all regimens, these data suggest that the length of time that the antibacterial activity was maintained over the dosing interval with these combinations was dictated by the pharmacokinetics of the beta-lactamase inhibitor in the combination. The antibacterial activity of the combination appeared to be lost when the amount of inhibitor available fell below some critical concentration. This critical concentration varied depending upon the type and amount of enzyme produced, as well as the specific inhibitor used. These results indicate that the antibacterial activity of drug-inhibitor combinations, when dosed at their currently recommended ratios, is more dependent on the pharmacokinetics of the inhibitor than on those of the beta-lactam drug.

scholarly journals Replacement of Albumin by Preovulatory Oviductal Fluid in Swim-Up Sperm Preparation Method Modifies Boar Sperm Parameters and Improves In Vitro Penetration of Oocytes

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1202
Author(s):  
Sergio Navarro-Serna ◽  
Evelyne París-Oller ◽  
Ondrej Simonik ◽  
Raquel Romar ◽  
Joaquín Gadea
Keyword(s):  
Calcium Concentration ◽  
Preparation Method ◽  
Culture Media ◽  
Penetration Rate ◽  
Sperm Parameters ◽  
High Concentration ◽  
Sperm Preparation ◽  
Boar Sperm ◽  
Oviductal Fluid

More suitable and efficient methods to protect gametes from external harmful effects during in vitro handling can be achieved by adding preovulatory porcine oviductal fluid (pOF) to in vitro culture media. The objective of this study was to assess the swim-up procedure’s suitability as a sperm selection method using a medium supplemented with 1mg/mL BSA, 1% preovulatory pOF (v/v), 1% v/v pOF plus 1mg/mL BSA, and 5mg/mL BSA. After selection, various sperm parameters were studied, such as sperm recovery rate, sperm morphology, motility (by CASA), vitality, acrosome status and intracellular calcium (by flow cytometry) and ability to penetrate oocytes in vitro. Around 2% of sperm were recovered after swim-up, and the replacement of BSA by pOF showed a beneficial reduction of motility parameters calcium concentration, resulting in an increased penetration rate. The combination of albumin and oviductal fluid in the medium did not improve the sperm parameters results, whereas a high concentration of BSA increased sperm morphological abnormalities, motility, and acrosome damage, with a reduction of calcium concentration and penetration rate. In conclusion, the replacement of albumin by preovulatory oviductal fluid in the swim-up sperm preparation method modifies boar sperm parameters and improves the in vitro penetration of oocytes.

scholarly journals Inhibition of Glycolysis Suppresses Cell Proliferation and Tumor Progression In Vivo: Perspectives for Chronotherapy

2021 ◽  
Vol 22 (9) ◽  
pp. 4390
Author(s):  
Jana Horváthová ◽  
Roman Moravčík ◽  
Miroslava Matúšková ◽  
Vladimír Šišovský ◽  
Andrej Boháč ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Tumor Progression ◽  
Umbilical Vein ◽  
Cell Metabolism ◽  
High Rate ◽  
Ki 67 ◽  
Immunodeficient Mice ◽  
Inhibition Of Glycolysis

A high rate of glycolysis is considered a hallmark of tumor progression and is caused by overexpression of the enzyme 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3). Therefore, we analyzed the possibility of inhibiting tumor and endothelial cell metabolism through the inhibition of PFKFB3 by a small molecule, (E)-1-(pyridin-4-yl)-3-(quinolin-2-yl)prop-2-en-1-one (PFK15), as a promising therapy. The effects of PFK15 on cell proliferation and apoptosis were analyzed on human umbilical vein endothelial cells (HUVEC) and the human colorectal adenocarcinoma cell line DLD1 through cytotoxicity and proliferation assays, flow cytometry, and western blotting. The results showed that PFK15 inhibited the proliferation of both cell types and induced apoptosis with decreasing the Bcl-2/Bax ratio. On the basis of the results obtained from in vitro experiments, we performed a study on immunodeficient mice implanted with DLD1 cells. We found a reduced tumor mass after morning PFK15 treatment but not after evening treatment, suggesting circadian control of underlying processes. The reduction in tumor size was related to decreased expression of Ki-67, a marker of cell proliferation. We conclude that inhibition of glycolysis can represent a promising therapeutic strategy for cancer treatment and its efficiency is circadian dependent.

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