Tissue-specific mitochondrial functionality and mitochondrial-related gene profiles in response to maternal nutrition and one-carbon metabolite supplementation during early pregnancy in heifers

Authors: SAFAIN, KAZI - North Dakota State University; Crouse, Matthew; HIRCHERT, MARA - North Dakota State University; ENTZIE, YSSI - North Dakota State University; SYRING, JESSICA - North Dakota State University; DANESHI, MOJTABA - North Dakota State University; ANAS, MUHAMMAD - North Dakota State University; KING, LAYLA - University Of Minnesota Crookston; REYNOLDS, LAWRENCE - North Dakota State University; BOROWICZ, PAWEL - North Dakota State University; DAHLEN, CARL - North Dakota State University; WARD, ALISON - University Of Saskatchewan; CATON, JOEL - North Dakota State University; SWANSON, KENDALL - North Dakota State University

Submitted to: Animals
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/9/2025
Publication Date: 9/14/2025
Citation: Safain, K.S., Crouse, M.S., Hirchert, M.R., Entzie, Y.L., Syring, J.G., Daneshi, M., Anas, M., King, L.E., Reynolds, L.P., Borowicz, P.P., Dahlen, C.R., Ward, A.K., Caton, J.S., Swanson, K.C. 2025. Tissue-specific mitochondrial functionality and mitochondrial-related gene profiles in response to maternal nutrition and one-carbon metabolite supplementation during early pregnancy in heifers. Animals. 15. Article 2689. https://doi.org/10.3390/ani15182689.
DOI: https://doi.org/10.3390/ani15182689

Interpretive Summary: Lay summary Mitochondria are essential for fetal development because they regulate energy production and play a key role in long-term health. This study examined how maternal nutrition and supplementation with one-carbon metabolites (OCM)--including methionine, choline, folate, and vitamin B12--during early pregnancy influence fetal mitochondrial function in beef heifers at mid-gestation. Heifers were fed different diets during the first 63 days of pregnancy, varying in both their rate of weight gain and whether they received OCM supplements. At day 161 of gestation, mitochondrial respiration, mitochondrial DNA copy number, and gene expression in fetal liver and muscle tissues were analyzed. The fetal liver responded strongly to OCM supplementation and restricted maternal weight gain, showing increased mitochondrial respiration and greater mitochondrial DNA copy number--indicators of enhanced energy metabolism. These changes occurred with minimal changes in gene expression, suggesting regulation may occur at the protein level. In contrast, fetal muscle showed no change in mitochondrial respiration with treatments but exhibited reduced expression of genes involved in fat metabolism and energy production, indicating early transcriptional reprogramming that may influence energy use after birth. These results emphasize early pregnancy as a critical window when maternal nutrition can shape fetal metabolic development in a tissue-specific manner, with lasting implications for calf growth and productivity.

Technical Abstract: Background: Mitochondria are essential for fetal development, regulating energy metabolism and metabolic programming. This study examined how maternal nutrition and one-carbon metabolite (OCM) supplementation during early gestation affect mitochondrial function in fetal liver and muscle at day 161 of gestation in beef heifers. Methods: Twenty-nine crossbred Angus heifers were assigned to one of four treatments in a 2 × 2 factorial design: control (CON; 0.45 kg/day ADG) or restricted gain (RES; -0.23 kg/day), with or without OCM supplementation. Treatments were applied from breeding to day 63 of gestation, after which all heifers received a common diet. Fetal liver and muscle tissues were collected at day 161. Mitochondrial respiration (Seahorse assay), mtDNA copy number (qPCR), and mitochondria-related gene expression (RNA-seq) were assessed. Results: In fetal liver, state 3 respiration was highest in CON+OCM, while state 4o respiration was lowest in RES+OCM (P