Effect of gestation dietary methionine-to-lysine ratio on methionine metabolism and antioxidant ability of high-prolific sows

Abstract

The uptake and metabolism of methionine (Met) are critical for epigenetic regulation, redox homeostasis, and embryo development. Our previous study showed that appropriate supplementation of dietary Met promoted the birth weight and placental angiogenesis of high-prolific sows. To further explore the metabolic effect of Met on pregnant sows, we have evaluated the influence of dietary Met level on Met metabolism, and the relationship between metabolites of Met and reproductive performance, antioxidant ability, and placental angiogenesis throughout the gestation of high-prolific sows. Sixty sows (the 3rd parity, Large White) were randomly divided into 5 groups that were fed diets with standardized ileal digestible (SID) methionine-to-lysine (Met:Lys) ratios of 0.27 (control), 0.32, 0.37, 0.42, and 0.47 from the mating day (gestational d 0, G0d) until the farrowing day. HPLC-MS/MS analysis was used to simultaneously evaluate the metabolites related to Met, e.g. S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH), homocysteine (Hcy), cysteine (Cys), and glutathione (GSH). The concentration of SAM and SAH in plasma had significant fluctuations, especially in late pregnancy. Increasing dietary Met supplementation significantly improved the plasma SAM and methylation potential (SAM-to-SAH ratio) at d 114 of pregnancy (G114d). Moreover, a positive association of the plasma SAM concentration at G114d was observed with the litter weight of born alive ( P < 0.05; R 2 = 0.58). Furthermore, Hcy concentration in plasma was at the lowest level for 0.37 ratio group at G114d. However, it significantly increased during late pregnancy. Moreover, there were negative correlations between plasma Hcy concentration at G114d ( P < 0.05) and the placental vascular density in the fold and stroma ( P < 0.05). Compared with the control group, the expression of vascular endothelial growth factor-A ( VEGF-A ) in the placenta tissue of 0.37 ratio group increased significantly ( P < 0.05). Collectively, these findings indicate that dietary Met:Lys ratio (0.37 to 0.57) in the pregnant diet dose not influence the antioxidant ability of the high-prolific sows; however, the improvement of fetal development and placental angiogenesis of high-prolific sows by supplementation of Met are closely associated to the key Met-related metabolite of SAM and Hcy, respectively.

Maternal folic acid and vitaminB12supplementation during medium to late gestation promotes fetal development via improving placental antioxidant capacity, angiogenesis and amino acid transport

“…34,35 In the current study, maternal Hcy levels increased significantly during mid-to-late gestation, consistent with previous research. 5 Elevated Hcy levels induce the generation of ROS in endothelial cells, 36 which may partly explain the increased systemic oxidative stress in sows during late gestation. 30 Oxidative stress is known to inhibit the mTORC1 signaling pathway, 37 leading to autophagic cell death.…”

“…Placental samples were collected from the placentas of piglets with a BW closest to the litter's average BW, and the specific method followed previous studies. 5 Eight sows were randomly selected from each group for placenta collection. Post sampling, placental samples were promptly frozen in liquid nitrogen and stored at −80 °C.…”

“…4 Previous studies have shown that maternal homocysteine (Hcy) levels in plasma rise significantly during late pregnancy. 5 Elevated Hcy levels can impair cellular function and negatively affect embryonic development by inducing oxidative stress, ultimately leading to IUGR. 6 Folic acid (FA) may facilitate the remethylation of Hcy, 7 and vitamin B 12 (VB 12 ), acting as its cofactor, is imperative for this metabolic pathway.…”

“…Oxidative stress has been identified as a critical factor in hindering fetal development 4 . Previous studies have shown that maternal homocysteine (Hcy) levels in plasma rise significantly during late pregnancy 5 . Elevated Hcy levels can impair cellular function and negatively affect embryonic development by inducing oxidative stress, ultimately leading to IUGR 6 …”

Dietary methionine deficiency stunts growth and increases fat deposition via suppression of fatty acids transportation and hepatic catabolism in Pekin ducks

“…Because of amino acids balance in diets, the utilization of other amino acids might be influenced by Met deficiency. For instance, dietary Met-to-lysine ratio affected Met metabolism in pregnant sow [ 35 ]. Dietary Met requirements of Pekin ducks from 15 to 42 days of age for optimal FCR were 0.38% and 0.42%, respectively, based on the linear broken line and quadratic broken line regression models ( Table S2 ), close to the Met requirement (0.40%) recommended by Meat Duck Feeding Standard of China (NY/T 2122-2012) [ 36 ], but greater than the recommendation (0.30%) by NRC (1994) [ 24 ].…”