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 Red LED Light Acts on the Mitochondrial Electron Chain of Donkey Sperm and Its Effects Depend on the Time of Exposure to Light

2020 ◽  
Vol 8 ◽  
Author(s):  
Jaime Catalán ◽  
Marion Papas ◽  
Lina Trujillo-Rojas ◽  
Olga Blanco-Prieto ◽  
Sebastián Bonilla-Correal ◽  
...  
Keyword(s):  
Red Light ◽  
Specific Inhibitor ◽  
Motile Sperm ◽  
Light Stimulation ◽  
Led Light ◽  
Mitochondrial Atp Synthase ◽  
Red Led ◽  
Oligomycin A ◽  
Rate Of Oxygen Consumption ◽  
Stimulation Of

This work aimed to investigate how stimulation of donkey sperm with red LED light affects mitochondrial function. For this purpose, freshly diluted donkey semen was stimulated with red light for 1, 5, and 10 min, in the presence or absence of oligomycin A (Omy A), a specific inhibitor of mitochondrial ATP synthase, or FCCP, a specific disruptor of mitochondrial electron chain. The results obtained in the present study indicated that the effects of red LED light on fresh donkey sperm function are related to changes in mitochondria function. In effect, irradiation of donkey sperm resulted in an increase in mitochondrial membrane potential (MMP), the activity of cytochrome C oxidase and the rate of oxygen consumption. In addition, in the absence of oligomycin A and FCCP, light-stimulation augmented the average path velocity (VAP) and modified the structure of motile sperm subpopulations, increasing the fastest and most linear subpopulation. In contrast, the presence of either Omy A or FCCP abolished the aforementioned effects. Interestingly, our results also showed that the effects of red light depend on the exposure time applied, as indicated by the observed differences between irradiation protocols. In conclusion, our results suggest that exposing fresh donkey sperm to red light modulates the function of their mitochondria through affecting the activity of the electron chain. However, the extent of this effect depends on the irradiation pattern and does not exclude the existence of other mechanisms, such as those related to thermotaxis.

scholarly journals Effects of Axotomy on Cultured Sensory Neurons of Aplysia: Long-Term Injury-Induced Changes in Excitability and Morphology Are Mediated by Different Signaling Pathways

2008 ◽  
Vol 100 (6) ◽  
pp. 3209-3224 ◽  
Author(s):  
Supinder S. Bedi ◽  
Diancai Cai ◽  
David L. Glanzman
Keyword(s):  
Signaling Pathways ◽  
Sensory Neurons ◽  
Specific Inhibitor ◽  
Distinct Pattern ◽  
Extracellular Signal ◽  
Vitro Model ◽  
Induced Changes ◽  
And Control

To facilitate an understanding of injury-induced changes within the nervous system, we used a single-cell, in vitro model of axonal injury. Sensory neurons were individually dissociated from the CNS of Aplysia and placed into cell culture. The major neurite of some neurons was then transected (axotomized neurons). Axotomy in hemolymph-containing culture medium produced long-term hyperexcitability (LTH-E) and enhanced neuritic sprouting (long-term hypermorphogenesis [LTH-M]). Axotomy in the absence of hemolymph induced LTH-E, but not LTH-M. Hemolymph-derived growth factors may activate tyrosine receptor kinase (Trk) receptors in sensory neurons. To examine this possibility, we treated uninjured (control) and axotomized sensory neurons with K252a, an inhibitor of Trk receptor activity. K252a depressed the excitability of both axotomized and control neurons. K252a also produced a distinct pattern of arborizing outgrowth of neurites in both axotomized and control neurons. Protein kinase C (PKC) is an intracellular signal downstream of Trk; accordingly, we tested the effects of bisindolylmaleimide I (Bis-I), a specific inhibitor of PKC, on the axotomy-induced cellular changes. Bis-I blocked LTH-E, but did not disrupt LTH-M. Finally, because Trk activates the extracellular signal regulated kinase pathway in Aplysia sensory neurons, we examined whether this pathway mediates the injury-induced changes. Sensory neurons were axotomized in the presence of U0126, an inhibitor of mitogen-activated/extracellular receptor-regulated kinase. U0126 blocked the LTH-M due to axotomy, but did not impair LTH-E. Therefore distinct cellular signaling pathways mediate the induction of LTH-E and LTH-M in the sensory neurons.

scholarly journals Stimulation of Mitochondrial ATP Synthase Activity – a New Diazoxide-Mediated Mechanism of Cardioprotection

2016 ◽  
pp. S119-S127 ◽  
Author(s):  
M. JAŠOVÁ ◽  
I. KANCIROVÁ ◽  
M. MURÁRIKOVÁ ◽  
V. FARKAŠOVÁ ◽  
I. WACZULÍKOVÁ ◽  
...  
Keyword(s):  
Membrane Fluidity ◽  
Atp Synthase ◽  
Mitochondrial Membrane ◽  
Isolated Heart ◽  
Myocardial Infarct ◽  
Direct Interaction ◽  
Myocardial Infarct Size ◽  
Mitochondrial Atp Synthase ◽  
Mitochondrial Membrane Fluidity

Pharmacological preconditioning by diazoxide and a model of experimental streptozotocin-induced acute diabetes mellitus (STZ-DM) provided similar levels of cardioprotection assessed as limiting myocardial infarct size. The aim was to explore the possibility of existence of another in vitro mechanism, which could be contributory to cardioprotection mediated by diazoxide treatment. Mitochondrial membrane fluidity and ATP synthase activity in isolated heart mitochondria were determined under the influence of two factors, STZ-DM condition and treatment with diazoxide. Both factors independently increased the ATP synthase activity (p<0.05), as no interaction effect was observed upon the combination of STZ-DM with diazoxide. On the other hand, the mitochondrial membrane fluidity was significantly increased by STZ-DM only; no significant main effect for diazoxide was found. Based on the results from measurements of enzyme kinetics, we assume a direct interaction of diazoxide with the molecule of ATP synthase stimulated its activity by noncompetitive activation. Our present work revealed, for the first time, that cardioprotection induced by diazoxide may not be caused exclusively by mitochondrial KATP opening, but presumably also by a direct interaction of diazoxide with ATP synthase, although the mechanisms for achieving this activation cannot be fully delineated.

Alveolar type II cell cNOS activity and ATP levels are increased by lung surfactant or DPPC vesicles

1997 ◽  
Vol 273 (2) ◽  
pp. L339-L346 ◽  
Author(s):  
P. R. Miles ◽  
L. Bowman ◽  
A. Rengasamy ◽  
L. Huffman
Keyword(s):  
Nitric Oxide ◽  
Lung Surfactant ◽  
Specific Inhibitor ◽  
Alveolar Type ◽  
Type Ii Cells ◽  
Type Ii ◽  
O2 Consumption ◽  
No Formation ◽  
Atp Levels ◽  
Type Ii Cell

In a previous study, we reported that nitric oxide (.NO) affects surfactant synthesis and ATP levels in alveolar type II cells and suggested that there is constitutive nitric oxide synthase (cNOS) activity in the cells. In the present study, we performed experiments to confirm further the presence of cNOS and to determine the effects of lung surfactant on type II cell .NO and ATP levels. The supernatant from freshly isolated cells contains .NO (0.26 +/- 0.08 nmol/10(6) cells). During incubation, the cells produce additional .NO at a rate of approximately 0.3 nmol.10(5) cells-1.h-1. .NO formation is inhibited by 28-46% by three inhibitors of cNOS and inducible NOS (iNOS), NG-monomethyl-L-arginine (L-NMMA), L-N5-(1-iminoethyl)ornithine hydrochloride, and NG-nitro-L-arginine methyl ester, but a specific inhibitor of iNOS, aminoguanidine, has no effect. The production of .NO is reduced in Ca(2+)-free medium, is stimulated by the Ca2+ ionophore A-23187, and is independent of extracellular L-arginine. One known type of cNOS, endothelial NOS (eNOS), can be detected in the cells by using Western blot analysis. Incubation of the cells with lung surfactant leads to a relatively rapid (approximately 15 min), concentration-dependent increase in .NO formation that reaches levels as high as 238 +/- 14% of control. The surfactant effects appear to be caused by its major component, dipalmitoyl phosphatidylcholine (DPPC). Exposure of type II cells to DPPC results in maximal increases in .NO formation, ATP content, and O2 consumption, which are 268 +/- 32, 234 +/- 24, and 131 +/- 6% of control, respectively. The DPPC-induced increases in .NO, ATP, and O2 consumption are inhibited by L-NMMA. These results confirm the presence of type II cell cNOS and suggest that it may have a role in the cellular processing of lung surfactant.

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.

scholarly journals Red LED Light Acts on the Mitochondrial Electron Chain of Mammalian Sperm via Light-Time Exposure-Dependent Mechanisms

Cells ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 2546 ◽  
Author(s):  
Olga Blanco-Prieto ◽  
Jaime Catalán ◽  
Lina Trujillo-Rojas ◽  
Alejandro Peña ◽  
Maria Montserrat Rivera del Álamo ◽  
...  
Keyword(s):  
Mitochondrial Function ◽  
Red Light ◽  
Maximal Effect ◽  
O2 Consumption ◽  
Led Light ◽  
Intracellular Atp ◽  
Mammalian Sperm ◽  
Atp Levels ◽  
Red Led ◽  
Oligomycin A

This work analyzes the effects of red LED light on mammalian sperm mitochondrial function, using the pig as an animal model. Liquid-stored pig semen was stimulated with red-light for 1, 5 and 10 min in the presence or absence of oligomycin A, a specific inhibitor of mitochondrial ATP synthase, or carbonyl cyanide 4-(trifluoromethoxy)phenylhydrazone (FCCP), a specific disruptor of mitochondrial electron chain. Whereas exposure for 1 and 5 min significantly (p < 0.05) decreased total motility and intracellular ATP levels, irradiation for 10 min induced the opposite effect. Oligomycin A abolished the light-effects on intracellular ATP levels, O2 consumption and mitochondrial membrane potential, whereas compared to non-irradiated samples, FCCP significantly (p < 0.05) increased O2 consumption when sperm were irradiated for 1 min. Both oligomycin A and FCCP significantly (p < 0.05) decreased total motility. Red-light increased cytochrome c oxidase activity with a maximal effect after 5 min of irradiation, which was abolished by both oligomycin A and FCCP. In conclusion, red-light modulates sperm mitochondrial function via electron chain activity in an exposition, time-dependent manner.

ROCK-dependent ATP5D modulation contributes to the protection of notoginsenoside NR1 against ischemia-reperfusion-induced myocardial injury

2014 ◽  
Vol 307 (12) ◽  
pp. H1764-H1776 ◽  
Author(s):  
Ke He ◽  
Li Yan ◽  
Chun-Shui Pan ◽  
Yu-Ying Liu ◽  
Yuan-Chen Cui ◽  
...  
Keyword(s):  
Energy Metabolism ◽  
Cardiac Function ◽  
Atp Synthase ◽  
Ischemia Reperfusion ◽  
Glucose Deprivation ◽  
Oxygen And Glucose Deprivation ◽  
Metabolism Disorder ◽  
Mitochondrial Atp Synthase ◽  
Energy Metabolism Disorder

Cardiac ischemia-reperfusion (I/R) injury remains a challenge for clinicians, which initiates with energy metabolism disorder. The present study was designed to investigate the protective effect of notoginsenoside R1 (NR1) on I/R-induced cardiac injury and underlying mechanism. Male Sprague-Dawley rats were subjected to 30-min occlusion of the left coronary anterior descending artery followed by reperfusion with or without NR1 pretreatment (5 mg·kg−1·h−1). In vitro, H9c2 cells were cultured under oxygen and glucose deprivation/reoxygenation conditions after NR1 (0.1 mM), Rho kinase (ROCK) inhibitor Y-27632 (10 μM), or RhoA/ROCK activator U-46619 (10 nM) administration. Myocardial infarct size, myocardial histology, and cardiac function were evaluated. Myofibril and mitochondria morphology were observed by transmission electron microscopy. F-actin and apoptosis were determined by immunofluorescence and TUNEL staining. ATP and AMP content were assessed by ELISA. Phosphorylated-AMP-activated protein kinase, ATP synthase subunits, apoptosis-related molecules, and the level and activity of ROCK were determined by Western blot analysis. We found that NR1 pretreatment ameliorated myocardial infarction, histological injury, and cardiac function induced by I/R. Furthermore, similar to the effect of Y-27632, NR1 improved H9c2 cell viability, maintained actin skeleton and mitochondria morphology, and attenuated apoptosis induced by oxygen and glucose deprivation/reoxygenation. Importantly, NR1 prevented energy abnormity, inhibited the expression and activation of ROCK, and restored the expression of the mitochondrial ATP synthase δ-subunit both in vivo and in vitro, whereas U-46619 suppressed the effect of NR1. These results prove NR1 as an agent able to prevent I/R-induced energy metabolism disorder via inhibiting ROCK and enhancing mitochondrial ATP synthase δ-subunits, which at least partially contributes to its protection against cardiac I/R injury.

scholarly journals Antifungal Mechanism of Action of Lactoferrin: Identification of H+-ATPase (P3A-Type) as a New Apoptotic-Cell Membrane Receptor

2016 ◽  
Vol 60 (7) ◽  
pp. 4206-4216 ◽  
Author(s):  
María T. Andrés ◽  
Maikel Acosta-Zaldívar ◽  
José F. Fierro
Keyword(s):  
Plasma Membrane ◽  
Apoptotic Cell ◽  
Ion Homeostasis ◽  
Specific Inhibitor ◽  
Human Lactoferrin ◽  
Plasma Membrane Atpase ◽  
Content Type ◽  
Atp Levels ◽  
Mitochondrial Atp Synthase ◽  
Metabolic Conditions

ABSTRACTHuman lactoferrin (hLf) is a protein of the innate immune system which induces an apoptotic-like process in yeast. Determination of the susceptibility to lactoferrin of several yeast species under different metabolic conditions, respiratory activity, cytoplasmic ATP levels, and external medium acidification mediated by glucose assays suggested plasma membrane Pma1p (P3A-type ATPase) as the hLf molecular target. The inhibition of plasma membrane ATPase activity by hLf and the identification of Pma1p as the hLf-binding membrane protein confirmed the previous physiological evidence. Consistent with this, cytoplasmic ATP levels progressively increased in hLf-treatedCandida albicanscells. However, oligomycin, a specific inhibitor of the mitochondrial F-type ATPase proton pump (mtATPase), abrogated the antifungal activity of hLf, indicating a crucial role for mtATPase in the apoptotic process. We suggest that lactoferrin targeted plasma membrane Pma1p H+-ATPase, perturbing the cytoplasmic ion homeostasis (i.e., cytoplasmic H+accumulation and subsequent K+efflux) and inducing a lethal mitochondrial dysfunction. This initial event involved a normal mitochondrial ATP synthase activity responsible for both the ATP increment and subsequent hypothetical mitochondrial proton flooding process. We conclude that human lactoferrin inhibited Pma1p H+-ATPase, inducing an apoptotic-like process in metabolically active yeast. Involvement of mitochondrial H+-ATPase (nonreverted) was essential for the progress of this programmed cell death in which the ionic homeostasis perturbation seems to precede classical nonionic apoptotic events.

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