Effect of high‐density lipoprotein on oocyte maturation and bovine embryo development in vitro

Abstract

High‐density lipoprotein (HDL) is the main lipoprotein in the follicular fluid, and it has anti‐inflammatory, antioxidant and cryoprotectant properties. The anti‐inflammatory potential and antioxidant potential are derived from its lipid composition, especially the apolipoprotein AI (ApoAI) and paraoxonase 1 (PON1). The aim of this study was to evaluate the effect of HDL during in vitro maturation (IVM) on oocyte maturation and early bovine embryo development. For this, cumulus–oocyte complexes (COCs) were obtained from bovine ovaries collected at a local slaughterhouse. COCs (n = 2,250) were allocated into three groups (n = 50 COCs/group) according to the addition of HDL protein (HDL‐P) during IVM for 22 hr: 0 (control), 50 and 150 mg/dl. After IVM, COCs were inseminated (in vitro fertilization) and cultivated for 7 days. Total cholesterol concentration, total protein, triglycerides and ApoAI concentrations on IVM medium increased proportionally to HDL‐P addition. However, PON1 activity was not detected in any treatment. The addition of HDL‐P did not affect nuclear maturation rate, endogenous reactive oxygen species and glutathione levels in COCs (p > 0.05). The highest HDL‐P concentration (150 mg/dl) decreased cleavage and blastocyst rate (p < 0.05). Moreover, the HDL‐P 150 mg/dl group had lower cellular count/blastocyst than the 50 mg/dl group (p < 0.05). However, the addition of HDL‐P did not affect relative gene expression of evaluated genes. In conclusion, the complex HDL/ApoAI obtained from human plasma, in the absence of PON1 activity during in vitro oocyte maturation, decreased initial embryo development.

Effect of Milk-Feeding Frequency and Calcium Gluconate Supplementation on Growth, Health, and Reproductive and Metabolic Features of Holstein Heifers at a Rearing Farm

“…Heifers in group 2FG showed lower levels of high-density lipoprotein than those that had not received gluconate. High-density lipoprotein has anti-inflammatory and anti-oxidant properties [58], and higher levels may reflect a reaction to stress. Indeed, high-density lipoprotein levels increased across all four groups during the stressful situation of transfer into open-door pens.…”

Uterine Fluid Extracellular Vesicles Proteome Is Altered During the Estrous Cycle

“…Even with the addition of antioxidants, the in vitro embryos development still undergoes ROS-mediated oxidative stress ( 54 ). Some studies show that culture medium with correct dose of antioxidants protects embryos from oxidative stress ( 51 , 52 , 53 ); however some contrasting evidence has also been presented ( 55 , 56 ). Overall, it is necessary to control the oxidative stress conditions of embryos to have increased in vitro embryo quality.…”

Proteomic Analysis Identifies Distinct Protein Patterns for High Ovulation in FecB Mutant Small Tail Han Sheep Granulosa Cells

“…APOH and APOM are also associated with HDL function [ 53 ]. It has been reported that abnormal metabolism of HDL and its lipoprotein mutation affect fertility in females and also affect the maturation and embryo quality of oocytes matured in vitro [ 54 , 55 , 56 , 57 ]. HDL is the only major lipoprotein detected in follicular fluid, and HDL plays an important role in ovarian cholesterol transport [ 58 ].…”

“…These results are consistent with those reported for the ovarian proteome of ewes with different genotypes of FecB [ 19 ], suggesting that FecB mutant ewes can provide sufficient cholesterol for follicle development and thus produce more ovulated oocytes. It has been shown that increased paraoxonase 1 (PON1) and APOA1 can enhance the resistance of bovine oocytes to oxidative stress and improve embryo survival after in vitro fertilization and maturation of oocytes [ 57 , 64 ]. In the present study, it was found that PON1 and APOA1 were clustered in cluster 6, and the abundances of these proteins were significantly higher in both BB and WB types than in wild-type ewes.…”