Affiliation:
1. Animal Physiology and Reproduction Division ICAR‐Central Institute for Research on Buffaloes Hisar Haryana India
2. Department of Veterinary Gynaecology and Obstetrics Lala Lajpat Rai University of Veterinary and Animal Sciences Hisar Haryana India
Abstract
ABSTRACTProblemLipopolysaccharide (LPS) from gram‐negative bacteria has reportedly been associated with infectious diseases like metritis, which has a substantial adverse effect on animal reproductive performance and causes serious financial losses for the dairy sector. The current work aimed to establish the impact of LPS on in vitro oocyte maturation and subsequent in vitro developmental competence of oocytes, as well as to investigate the explanatory molecular mechanism underlying this effect.Method of StudyBuffalo cumulus‐oocyte complexes (COCs) were challenged with 0, 5, 10 and 20 µg/mL LPS during IVM followed by IVF and IVC. Cytoplasmic and nuclear maturation, cleavage and blastocyst rate, intracellular reactive oxygen species (ROS), mitochondrial membrane potential (MMP, ΔΨm) and transcript abundance of genes related to inflammation, antioxidation and apoptosis were evaluated.ResultsThe maturation and subsequent embryonic development competency were found to be significantly (p ≤ 0.05) reduced with the addition of 10 and 20 µg/mL LPS to IVM media. ROS production accompanied by a decreased ΔΨm was recorded in LPS‐treated oocytes in comparison to the control group (p ≤ 0.05). Our results were further supported by the transcriptional expression of proinflammatory (TLR4, CD14 and RPS27A) and apoptotic gene (Caspase 3) which were found to be significantly increased while antioxidant genes (SOD2 and GPX1) were decreased significantly in matured oocytes and blastocyst after LPS exposure.ConclusionsThe deleterious effects of LPS are mediated through ROS generation, which triggers inflammatory processes via the TLR4 pathway and impairs oocyte maturation and subsequent embryonic development.