Carbon Monoxide Exposure Does Not Improve The In Vitro Fertilization Rate of Oocytes Obtained from Heterozygous Hmox1 Knockout Mice

Document Type : Short Communication


1 Department of Environmental Immunology, UFZ-Helmholtz Centre for Environmental Research Leipzig- Halle, Leipzig, Germany

2 Perinatal Immunology, Saxon Incubator for Clinical Translation (SIKT), Medical Faculty, University Leipzig, Leipzig, Germany

3 Instituto de Salud y Ambiente del Litoral (ISAL, UNL-CONICET), Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral (UNL), Santa Fe, Argentina

4 Experimental Obstetrics and Gynecology, Medical Faculty, Otto-von-Guericke University, Magdeburg, Germany


In our experimental study, we explored the impact of maternal reduced heme oxygenase-1 (HO-1) gene (Hmox1)
expression on the in vitro fertilization (IVF) rate through the use of heterozygous Hmox1 knockout mice models
(HET/Hmox1+/ -). Also, we hypothesized a beneficial role of gametes exposure during fertilization to carbon monoxide
(CO), one of HO-1 by-products, that might be relevant for the improvement of IVF rates. IVF technique was
performed by using oocytes obtained from wild-type (WT) or Hmox1+/ - dams fertilized with WT, Hmox1+/ - or
Hmox1-/ - mice-derived sperm. The fertilization step occurred either in a conventional incubator (37°C, 5% CO2) or in
an incubator implemented with CO (500 ppm). The superovulation yield of WT and Hmox1+/ - mice and the number of
fertilized oocytes was assessed using an optical microscope. The dams’ Hmox1 heterozygous knockout neither impact
the superovulation yield, nor did influence the fertilization success rate. Moreover, CO exposure during fertilization
could not significantly improve the outcome. Our study showed that the maternal Hmox1+/ - condition is not affecting
the IVF rate in mice. Furthermore, we discovered that CO exposure cannot be exploited to ameliorate this critical step
of the IVF protocol.


Main Subjects


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