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Research article - Peer-reviewed, 2021

Matrix metalloproteinase (MMP)-2, MMP-9, semen quality and sperm longevity in fractionated stallion semen

Kareskoski, Maria; Vakkamaki, Johanna; Laukkanen, Kirsi; Palviainen, Mari; Johannisson, Anders; Katila, Terttu


Matrix metalloproteinase (MMP)-2 and MMP-9 are gelatinases that take part in several reproductive processes. The aim of this study was to measure levels of MMP-2 and MMP-9 in fractionated stallion ejaculates, and to evaluate the association between these components and semen quality, and sperm longevity during cooled storage. Semen quality were assessed separately for sperm-rich fractions (HIGH), sperm-poor fractions (LOW), and whole ejaculate samples (WE) from 33 stallions. After cooled storage with SP either present or removed, sperm motility and DFI were determined. The relative activity of the pro-form of MMP-2, active MMP-2 and total MMP-9 were evaluated using gelatin zymography, and all were present in all fractions of the stallion's ejaculate, with higher relative activity of the latent than active forms and the highest relative activity in the HIGH fraction. The relative activities of MMP-2 and MMP-9 were positively correlated to sperm concentration and total sperm count, but only in the HIGH fraction and not in LOW or WE. The relative activities of MMPs were not related to differences in sperm longevity during cooled storage, measured as sperm motility and DFI. There was a harmful effect of SP on DFI during storage, but this effect was not associated with differences in the relative activities of MMPs. In conclusion, the relative activities of MMPs are not useful as markers for semen quality (other than sperm concentration), or sperm survival during storage in horses. (C) 2021 Elsevier Inc. All rights reserved.


Stallion; Seminal plasma; Sperm longevity; Ejaculate; Matrix metalloproteinase

Published in

2021, volume: 164, pages: 93-99

Authors' information

Kareskoski, Maria
University of Helsinki
Vakkamaki, Johanna
University of Helsinki
Laukkanen, Kirsi
University of Helsinki
Palviainen, Mari
University of Helsinki
Swedish University of Agricultural Sciences, Department of Clinical Sciences
Katila, Terttu
University of Helsinki

UKÄ Subject classification

Clinical Science

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