Effects of Roundup and its main component, glyphosate, upon mammalian sperm function and survival

Successful sperm function leads to fertilization. It is dependent on the extracellular environment, especially the array and concentration of various ions. Considerable evidence indicates that this is because of consequent effects on the intracellular ionic composition. Although both cations and anions undoubtedly play a role in a modulating sperm function, most of the evidence currently available concerns cations. Therefore, this review will concentrate on cations, focussing on Ca2+, Na+, K+ and H+. Their requirements for successful capacitation (mammalian sperm) and acrosomal exocytosis (both invertebrate and mammalian sperm) will be considered. In particular, the mechanisms which may control ion fluxes, leading to changes in the intracellular ionic composition and subsequently to changes in sperm functional potential, will be addressed.

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Calcitonin acts as a first messenger to regulate adenylyl cyclase/cAMP and mammalian sperm function

Molecular Reproduction and Development ◽

10.1002/mrd.10273 ◽

2003 ◽

Vol 65 (2) ◽

pp. 228-236 ◽

Cited By ~ 17

Author(s):

S.A. Adeoya-Osiguwa ◽

L.R. Fraser

Keyword(s):

Adenylyl Cyclase ◽

Sperm Function ◽

Mammalian Sperm

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Exosomes derived from HEK293T cells interact in an efficient and noninvasive manner with mammalian sperm in vitro

Nanomedicine ◽

10.2217/nnm-2020-0056 ◽

2020 ◽

Vol 15 (20) ◽

pp. 1965-1980

Author(s):

Teresa Vilanova-Perez ◽

Celine Jones ◽

Stefan Balint ◽

Rebecca Dragovic ◽

Michael L Dustin ◽

...

Keyword(s):

Flow Cytometry ◽

Mitochondrial Membrane ◽

Membrane Integrity ◽

Computer Assisted ◽

Sperm Function ◽

Sperm Analysis ◽

Mammalian Sperm ◽

Boar Sperm ◽

Computer Assisted Sperm Analysis

Aim: To investigate exosomes as a noninvasive delivery tool for mammalian sperm. Materials & Methods: Exosomes were isolated from HEK293T cells and co-incubated with boar sperm in vitro. Results: Internalized exosomes were detected within 10 min of co-incubation. Computer-assisted sperm analysis and flow cytometry demonstrated that even after 5-h of exposure to exosomes, there were no significant deleterious effects with regard to sperm motility, viability, membrane integrity and mitochondrial membrane potential (p > 0.05), thus indicating that exosomes did not interfere with basic sperm function. Conclusion: HEK293T-derived exosomes interacted with boar sperm without affecting sperm function. Exosomes represent a versatile and promising research tool for studying sperm biology and provide new options for the diagnosis and treatment of male infertility.

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Deactivation of the JNK Pathway by GSTP1 Is Essential to Maintain Sperm Functionality

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.627140 ◽

2021 ◽

Vol 9 ◽

Author(s):

Marc Llavanera ◽

Yentel Mateo-Otero ◽

Ariadna Delgado-Bermúdez ◽

Sandra Recuero ◽

Samuel Olives ◽

...

Keyword(s):

Membrane Integrity ◽

Mitochondrial Activity ◽

Computer Assisted ◽

Sperm Function ◽

Jnk Pathway ◽

Male Subfertility ◽

Mammalian Sperm ◽

Genetic Abnormalities ◽

Protein Dysfunction

Fifty percent of male subfertility diagnosis is idiopathic and is usually associated with genetic abnormalities or protein dysfunction, which are not detectable through the conventional spermiogram. Glutathione S-transferases (GSTs) are antioxidant enzymes essential for preserving sperm function and maintaining fertilizing ability. However, while the role of GSTP1 in cell signaling regulation via the inhibition of c-Jun N-terminal kinases (JNK) has been enlightened in somatic cells, it has never been investigated in mammalian spermatozoa. In this regard, a comprehensive approach through immunoblotting, immunofluorescence, computer-assisted sperm assessment (CASA), and flow cytometry analysis was used to characterize the molecular role of the GSTP1–JNK heterocomplex in sperm physiology, using the pig as a model. Immunological assessments confirmed the presence and localization of GSTP1 in sperm cells. The pharmacological dissociation of the GSTP1–JNK heterocomplex resulted in the activation of JNK, which led to a significant decrease in sperm viability, motility, mitochondrial activity, and plasma membrane stability, as well as to an increase of intracellular superoxides. No effects in intracellular calcium levels and acrosome membrane integrity were observed. In conclusion, the present work has demonstrated, for the first time, the essential role of GSTP1 in deactivating JNK, which is crucial to maintain sperm function and has also set the grounds to understand the relevance of the GSTP1–JNK heterocomplex for the regulation of mammalian sperm physiology.

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Glutathione S-Transferases Play a Crucial Role in Mitochondrial Function, Plasma Membrane Stability and Oxidative Regulation of Mammalian Sperm

Antioxidants ◽

10.3390/antiox9020100 ◽

2020 ◽

Vol 9 (2) ◽

pp. 100 ◽

Cited By ~ 3

Author(s):

Marc Llavanera ◽

Ariadna Delgado-Bermúdez ◽

Samuel Olives ◽

Yentel Mateo-Otero ◽

Sandra Recuero ◽

...

Keyword(s):

Plasma Membrane ◽

Mitochondrial Function ◽

Sperm Quality ◽

Mammalian Species ◽

Membrane Stability ◽

Sperm Function ◽

Cell Protection ◽

Mammalian Sperm ◽

Boar Sperm ◽

Glutathione S Transferases

Glutathione S-transferases (GSTs) are essential sperm antioxidant enzymes involved in cell protection against oxidative stress and toxic chemicals, preserving sperm function and fertilising ability. Artificial insemination (AI) in pigs is commonly carried out through the use of liquid-stored semen at 17 °C, which not only reduces sperm metabolic activity but also sperm quality and AI-farrowing rates within the 72 h of storage. While one may reasonably suggest that such enzymes are implicated in the physiology and maintenance of mammalian sperm function during liquid-storage, no previous studies conducted on any species have addressed this hypothesis. Therefore, the objective of the present work was to characterise the presence and function of sperm GSTs in mammalian sperm, using the pig as a model. In this regard, inhibition of such enzymes by ethacrynic acid (EA) during semen storage at 17 °C was performed to evaluate the effects of GSTs in liquid-preserved boar sperm by flow cytometry, immunofluorescence, and immunoblotting analysis. The results of this study have shown, for the first time in mammalian species, that the inhibition of GSTs reduces sperm quality and functionality parameters during their storage at 17 °C. These findings highlight the key role of such enzymes, especially preserving mitochondrial function and maintaining plasma membrane stability. In addition, this study has identified and localised GSTM3 in the tail and equatorial subdomain of the head of boar sperm. Finally, this study has set grounds for future investigations testing supplementation of semen extenders with GSTs, as this may improve fertility outcomes of swine AIs.

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Role of fertilization promoting peptide FPP in modulating mammalian sperm function

Frontiers in Bioscience ◽

10.2741/a355 ◽

1998 ◽

Vol 3 (4) ◽

pp. d1187-1191 ◽

Cited By ~ 2

Author(s):

Lynn R Fraser

Keyword(s):

Sperm Function ◽

Mammalian Sperm

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185 TRANSIENT RECEPTOR POTENTIAL CHANNEL-2 (TRPP2) REGULATES MOTILITY AND INTRACELLULAR CALCIUM OF PORCINE SPERM

Reproduction Fertility and Development ◽

10.1071/rdv28n2ab185 ◽

2016 ◽

Vol 28 (2) ◽

pp. 223

Author(s):

B. W. Daigneault ◽

D. J. Miller

Keyword(s):

Membrane Protein ◽

Intracellular Calcium ◽

Transient Receptor Potential ◽

Beat Frequency ◽

Receptor Potential ◽

Transient Receptor Potential Channel ◽

Sperm Function ◽

Cystic Kidneys ◽

Mammalian Sperm ◽

Transient Receptor

Transient receptor potential channel-2 (TRPP2) is a membrane protein important for the regulation of calcium homeostasis in renal epithelial cells. Mutations in human TRPP2 cause enlarged cystic kidneys and contribute to polycystic kidney disease. In addition, TRPP2 functions have been described in some invertebrate sperm and are related to sperm-egg interactions and mating. Male Drosophila with mutated TRPP2 display a mild sperm motility phenotype but have a drastic reduction in fertility due to failed sperm migration and storage within the female tract. Although TRPP2 has critical roles for Drosophila sperm function, the protein has not been described in mammalian sperm. The TRPP2 mutations affecting sperm function could explain idiopathic subfertility that is not detected when evaluating sperm by routine analyses. Herein we report the location of TRPP2 in porcine sperm and have identified functions of TRPP2 in regulating sperm functions important for fertility. The TRPP2 was detected as a 110-kDa band in protein lysates from sperm after capacitation or mock incubation in conditions that do not capacitate sperm. With immunofluorescence, TRPP2 was most abundant on the head and principal piece of sperm with more consistent staining patterns when sperm were maintained in non-capacitating medium. Inhibition of TRPP2 by antiserum resulted in a reduction in sperm average path and curvilinear velocity and an increase in tail cross-beat frequency when sperm were incubated in capacitating conditions. Sperm incubated with TRPP2 antiserum also had a significant decrease in intracellular calcium concentration compared with control samples and failed to undergo an increase in calcium over 90 min that is characteristic of capacitating sperm. TRPP2 is a previously unreported mammalian sperm membrane protein that appears to function as an ion channel to regulate calcium and capacitation-like changes in porcine sperm. This project is supported by Agriculture and Food Research Initiative Competitive Grant no. 2011–67015–20099 and 2015–67015–23228 from the USDA National Institute of Food and Agriculture.

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