Peripheral leucocyte molecular indicators of inflammation and oxidative stress are altered in dairy cows with embryonic loss

Abstract

Objective of experiment was to determine whether oxidative stress (OS) and inflammation altered embryonic loss in dairy cows. Blood samples were collected at days 0, 16, 32 and 60 after timed (AI) from 200 Holstein cows to determine embryonic loss based on interferon-stimulated gene-15 (ISG15) mRNA expression (day 16) and ultrasound at day 32 and day 60. Leucocyte expressions of mRNA TLR2, TLR4, TNF-α, IL1B, IL10, STAT3 (inflammation), PTGS2, PTGES (prostaglandin synthesis), and PLA2G4A and ALOX5AP (eicosanoid metabolism) at days 0 and 16 were determined. Plasma redox status for antioxidant enzymatic activities of glutathione peroxidase (GPX), superoxide dismutase (SOD), total antioxidant capacity (TAC), and concentrations of malondialdehyde (MDA) were determined at days 0, 16, 32 and 60. All antioxidant-redox responses were beneficially significant in pregnant cows diagnosed pregnant at day16 and sustained pregnancy to day 60 compared to non-pregnant cows at day16 or pregnant at day16 and lost embryos by days 32 or 60. The leucocyte mRNA expressions of TLR2, TLR4, STAT 3, IL1B, PTGS2, PLA2G4A and ALOX5AP were greater and PTGES was lower at day16 in pregnant cows that lost embryos early (P < 0.05). In conclusion peripheral leucocyte molecular indicators of inflammation and plasma indicators of OS were altered in pregnant cows undergoing embryonic losses compared to cows with a sustained pregnancy.

Melatonin as a Smart Protector of Pregnancy in Dairy Cows

“…The relatively greater values of TBARS and AOPP in cows with early embryonic loss are indicative of oxidative damage of lipids (TBARS) and proteins (AOPP) ( Figure 1 ). Similar results were described by Dirandeh et al (2021) [ 3 ] reporting decreased total antioxidant capacity (TAC), SOD and GPx in cows with embryonic loss, as well as increased lipid peroxidation. Zhao et al (2019) [ 35 ] reported that GPx abundance was greater in cyclic cows compared to cows with inactive ovaries, suggesting that OS in ovaries may lead to failure in follicular development to form a cumulus structure that promotes oocyte production.…”

“…Pregnancy status at day 16 after TAI was predicted via blood cell ISG15 mRNA gene expression. Prediction of pregnancy was based on blood cellular ISG15 expression greater than −7.0 at day 16 after TAI [ 3 , 21 ]. Pregnancy at day 32 after TAI was diagnosed via transrectal ultrasonography.…”

“…Complementary DNA (cDNA) was synthesized from 150 ng RNA using a QuantiTect Reverse Transcription kit (Qiagen, Hilden, Germany, Cat No. 205314), as described by Dirandeh et al (2021) [ 3 ].…”

“…204052), 1 mL of each forward and reverse primers and 4.5 mL of distilled H 2 O in a Rotor-Gene 6000 Real-Time PCR software (Corbett Research, Sydney, Australia) with specific bovine primers: melatonin receptor 1 (MT1 , [ 27 ]), mouse double minute 2 ( MDM2 ), MDM2 binding protein ( MTBP ), BCL2-associated X Apoptosis Regulator ( BAX ), p53 upregulated modulator of apoptosis (PUMA, gene symbol BBC3 , [ 17 ]), Mucin 1 ( MUC1 , [ 28 ]) and leukemia inhibitory factor ( LIF , [ 29 ]), in accordance with MIQE guidelines [ 30 ] and using following temperature program: 2 min at 50 °C, 10 min at 95 °C, 40 cycles of 15 s at 95 °C, and 1 min at 60 °C. The internal controls were GAPDH , RPS9 , and UXT [ 3 ]. The geometric mean of the internal control genes was used to normalize the expression data.…”

“…The causes of embryonic loss and sustained pregnancy are multifaceted through maternal and embryonic factors. A considerable number of embryonic losses are attributed to maternal factors, such as an inability of the uterus to support conceptus growth and implantation [ 2 , 3 , 4 ] and increased oxidative stress [ 5 ]. Oxidative stress, inflammatory status, and mRNA expression of white blood cells in postpartum lactating cows are associated with reproductive responses after Timed AI [ 3 ].…”