Maternal short and medium chain fatty acids supply during early pregnancy improves embryo survival through enhancing progesterone synthesis in rats.

Exploring strategies to prevent miscarriage in women or early pregnancy loss in mammals is of great importance. Manipulating maternal lipid metabolism to maintain sufficient progesterone level is an effective way. To investigated the embryo loss and progesterone synthesis impacts of short and medium chain fatty acids on the lipid metabolism, pregnancy outcome and embryo implantation were investigated in rats fed the pregnancy diets supplemented without or with 0.1% sodium butyrate (SB), 0.1% sodium hexanoate (SH), or 0.1% sodium caprylate (SC) during the entire pregnancy and early pregnancy, respectively, followed with evaluation of potential mechanisms. Maternal SB, SH, or SC supply significantly improved live litter size and embryo implantation in rats. Serum progesterone, arachidonic acid, and phospholipid metabolites levels were significantly increased in response to maternal SB, SH, and SC supply. The expression of key genes involved in ovarian steroidogenesis and granulosa cell luteinization were elevated in ovaries and primary cultured granulosa cells, including cluster of differentiation 36 (CD36), steroidogenic acute regulatory protein (StAR), and cholesterol side-chain cleavage enzyme (CYP11A1). Additionally, the expression of lysophosphatidic acid receptor 3 (LPA3) and cyclooxygenase-2 (COX2) related with phospholipid metabolism were enhanced in uterus in vivo and in in vitro cultured uterine tissue. In conclusion, maternal SB, SH and SC supply reduced early pregnancy loss through modulating maternal phospholipid metabolism and ovarian progesterone synthesis in rats. Our results have important implications that short or medium chain fatty acids have the potential to prevent miscarriage in women or early pregnancy loss in mammals.

Maternal N-Carbamylglutamate Supply during Early Pregnancy Enhanced Pregnancy Outcomes in Sows through Modulations of Targeted Genes and Metabolism Pathways.

Reducing pregnancy loss is important for improving reproductive efficiency for both human and mammalian animals. Our previous study demonstrates that maternal N-carbamylglutamate (NCG) supply during early pregnancy enhances embryonic survival in gilts. However, whether maternal NCG supply improves the pregnancy outcomes is still not known. Here we found maternal NCG supply during early pregnancy in sows significantly increased the numbers of total piglets born alive per litter ( P < 0.05) and significantly changed the levels of metabolites in amniotic fluid and serum involved in metabolism of energy, lipid, and glutathione and immunological regulation. The expression of endometrial progesterone receptor membrane component 1 (PGRMC1) was significantly increased by NCG supplementation ( P < 0.05) as well as the expression of PGRMC1, endothelial nitric oxide synthesases (eNOS), and lamin A/C in fetuses and placentae ( P < 0.05). Among the NCG-associated amino acids, arginine and glutamine, markedly increased PGRMC1 and eNOS expression in porcine trophectoderm cells ( P < 0.05), whereas glutamate could stimulate the expression of vimentin and lamin A/C in porcine trophectoderm (pTr) cells ( P < 0.05) and proline stimulated lamin A/C expression ( P < 0.05). Collectively, these data reveal the mechanisms of NCG in reducing early embryo loss. These findings have important implications that NCG has great potential to improve pregnancy outcomes in human and mammalian animals.

Dietary N-Carbamylglutamate Supplementation in a Reduced Protein Diet Affects Carcass Traits and the Profile of Muscle Amino Acids and Fatty Acids in Finishing Pigs.

The aim of this study was to investigate whether dietary N-carbamylglutamate (NCG) supplementation in a reduced protein diet affected carcass traits and meat quality in finishing pigs. A total of 120 gilts were randomly assigned to one of four treatments for 40 days, including a standard protein diet (SP), a reduced protein diet supplemented with 1.7% l-alanine (RP + Ala), a reduced protein diet supplemented with 1.0% l-arginine (RP + Arg), and a reduced protein diet supplemented with 0.1% NCG and 1.7% l-alanine (RP + NCG). NCG supplementation increased the endogenous synthesis of l-arginine. The RP + NCG diet significantly increased the loin eye area (p < 0.05) and tended to decrease the 10th rib fat depth (p = 0.08). NCG supplementation in a reduced protein diet was effective to produce functional pork with a high content of leucine (p < 0.05). The composition of several ω-6 and ω-3 polyunsaturated fatty acids (PUFAs) but not the ratio of ω-6/ω-3 PUFAs in muscles was altered in finishing pigs with dietary NCG supplementation. In conclusion, the RP + NCG diet is effective to increase the longissimus dorsi muscle area, decrease back fat accretion, and produce functional pork with a high content of leucine but without a negative impact on the muscle fatty acid profile in finishing pigs.