Mitochondrial aquaporin-8-mediated hydrogen peroxide transport is essential for teleost spermatozoon motility
Publication date
2015-01-14ISSN
2045-2322
Abstract
Reactive oxygen species (ROS), particularly hydrogen peroxide (H2O2), cause oxidative cell damage and inhibit sperm function. In most oviparous fishes that spawn in seawater (SW), spermatozoa may be exposed to harmful ROS loads associated with the hyperosmotic stress of axonemal activation and ATP synthesis from mitochondrial oxidative phosphorylation. However, it is not known how marine spermatozoa can cope with the increased ROS levels to maintain flagellar motility. Here, we show that a marine teleost orthologue of human aquaporin-8, termed Aqp8b, is rapidly phosphorylated and inserted into the inner mitochondrial membrane of SW-activated spermatozoa, where it facilitates H2O2 efflux from this compartment. When Aqp8b intracellular trafficking and mitochondrial channel activity are
immunologically blocked in activated spermatozoa, ROS levels accumulate in the mitochondria leading to
mitochondrial membrane depolarisation, the reduction of ATP production, and the progressive arrest of
sperm motility. However, the decreased sperm vitality underlying Aqp8b loss of function is fully reversed in the presence of a mitochondria-targeted antioxidant. These findings reveal a previously unknown
detoxification mechanism in spermatozoa under hypertonic conditions, whereby mitochondrial
Aqp8b-mediated H2O2 efflux permits fuel production and the maintenance of flagellar motility.
Document Type
Article
Document version
Published version
Language
English
Subject (CDU)
639 - Hunting. Fishing. Fish breeding
Pages
10
Publisher
Nature Research
Is part of
Scientific Reports
Citation
Chauvigné, François, Mónica Boj, Roderick Nigel Finn, and Joan Cerdà. 2015. "Mitochondrial Aquaporin-8-Mediated Hydrogen Peroxide Transport Is Essential For Teleost Spermatozoon Motility". Scientific Reports 5 (1). doi:10.1038/srep07789.
Grant agreement number
MICINN/Programa Nacional de Proyectos de Investigación Fundamental/AGL2010-15597/ES/AQUAPORINAS TESTICULARES DURANTE LA ESPERMATOGENESIS DE PECES MARINOS Y LA ACTIVACION Y PERMEABILIDAD ESPERMATICA/
Program
Aqüicultura
This item appears in the following Collection(s)
- ARTICLES CIENTÍFICS [2503]
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Except where otherwise noted, this item's license is described as http://creativecommons.org/licenses/by-nc-nd/4.0/