Short S
Universidad de La Frontera, Chile
Title: Study of the potential use of antifreeze proteins of Deschampsia antarctica in the cryopreservation of Salmo salar spermatozoa
Biography
Biography: Short S
Abstract
Cryopreservation allows to preserve genetic resources in aquatic species, such as Atlantic salmon (Salmo salar). However,
freezing may cause cell damage aff ecting the sperm quality. New procedures including antifreeze proteins (AFPs) seem
to improve sperm quality aft er cryopreservation. AFPs have the ability to bind to ice crystals inhibiting their growth, and ice
recrystallization (IRI) in vitro. Deschampsia antarctica is a freezing tolerante vascular plant species (LT50 -27°C) exhibiting
apoplastic antifreeze activity. We hypothesize that AFPs from D. antarctica favor the sperm quality of cryopreserved S.
salar spermatozoa. Th e aim of this work is to evaluate cryoprotection of AFPs from D. antarctica in S. salar spermatozoa.
Cryopreservation of S. salar spermatozoa has been made with a standard freezing medium (C+) and diff erent treatments with
protein extracts (20 μg/ml) of D. antarctica supplemented with permeating, DMSO 1.3 M, glucose 0.3 M, and non-permeating,
BSA 2% w/v cryoprotectants. Post-thawing plasma membrane integrity (PMI) by SYBR-14/PI and mitochondrial membrane
potential (MMP) by JC-1 markers were assessed using fl ow cytometry. Th awed cells in the presence of protein extracts from
D. antarctica without BSA maintained PMI as well as C+ and showed signifi cant diff erences respect to the other treatments.
Th e percentage of cells thawed with protein extracts of D. antarctica and with cryoprotectants showed higher MMP than C+.
While, treatments without permeating and non-permeating cryoprotectants maintained a similar MMP to C+. AFPs from
D. antarctica showed a cryoprotective eff ect in S. salar spermatozoa and these would act as non-permeating cryoprotectant,
replacing BSA in standard freezing medium.