Lactation alters the relationship between liver lipid synthesis and hepatic fat stores in the postpartum period
In mothers who are nursing their infants, increased clearance of plasma metabolites into the mammary gland may reduce ectopic lipid in the liver. No study to date has investigated the role of lactation on liver lipid synthesis in humans, and we hypothesized that lactation would modify fatty acid and...
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| Format: | Article |
| Language: | English |
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Elsevier
2022-11-01
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| Series: | Journal of Lipid Research |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S0022227522001213 |
| _version_ | 1798015631822422016 |
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| author | Maria A. Ramos-Roman Majid M. Syed-Abdul Brian M. Casey Jeffry R. Alger Yu-Lun Liu Elizabeth J. Parks |
| author_facet | Maria A. Ramos-Roman Majid M. Syed-Abdul Brian M. Casey Jeffry R. Alger Yu-Lun Liu Elizabeth J. Parks |
| author_sort | Maria A. Ramos-Roman |
| collection | DOAJ |
| description | In mothers who are nursing their infants, increased clearance of plasma metabolites into the mammary gland may reduce ectopic lipid in the liver. No study to date has investigated the role of lactation on liver lipid synthesis in humans, and we hypothesized that lactation would modify fatty acid and glucose handling to support liver metabolism in a manner synchronized with the demands of milk production. Lactating (n = 18) and formula-feeding women (n = 10) underwent metabolic testing at 6-week postpartum to determine whether lactation modified intrahepatic triacylglycerols (IHTGs), measured by proton magnetic resonance spectroscopy. Subjects ingested oral deuterated water to measure fractional de novo lipogenesis (DNL) in VLDL-TG during fasting and during an isotope-labeled clamp at an insulin infusion rate of 10 mU/m2/min. Compared with formula-feeding women, we found that lactating women exhibited lower plasma VLDL-TG concentrations, similar IHTG content and similar contribution of DNL to total VLDL-TG production. These findings suggest that lactation lowers plasma VLDL-TG concentrations for reasons that are unrelated to IHTG and DNL. Surprisingly, we determined that the rate of appearance of nonesterified fatty acids was not related to IHTG in either group, and the expected positive association between DNL and IHTG was only significant in formula-feeding women. Further, in lactating women only, the higher the prolactin concentration, the lower the IHTG, while greater DNL strongly associated with elevations in VLDL-TG. In conclusion, we suggest that future studies should investigate the role of lactation and prolactin in liver lipid secretion and metabolism. |
| first_indexed | 2024-04-11T15:38:01Z |
| format | Article |
| id | doaj.art-42e53016f3c44952aced6d09f65d9fac |
| institution | Directory Open Access Journal |
| issn | 0022-2275 |
| language | English |
| last_indexed | 2024-04-11T15:38:01Z |
| publishDate | 2022-11-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of Lipid Research |
| spelling | doaj.art-42e53016f3c44952aced6d09f65d9fac2022-12-22T04:15:55ZengElsevierJournal of Lipid Research0022-22752022-11-016311100288Lactation alters the relationship between liver lipid synthesis and hepatic fat stores in the postpartum periodMaria A. Ramos-Roman0Majid M. Syed-Abdul1Brian M. Casey2Jeffry R. Alger3Yu-Lun Liu4Elizabeth J. Parks5Division of Endocrinology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA; For correspondence: Maria A. Ramos-RomanDepartment of Nutrition and Exercise Physiology, University of Missouri School of Medicine, Columbia, MO, USADivision of Maternal and Fetal Medicine, Department of Obstetrics & Gynecology, University of Alabama, Birmingham, AL, USAAdvanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA; Neurospectroscopics LLC, Sherman Oaks, CA, USA; Department of Neurology, Geffen School of Medicine at UCLA, University of California, Los Angeles, Los Angeles, CA, USA; Hura Imaging, Calabassas, CA, USADepartment of Population and Data Sciences, University of Texas Southwestern Medical Center, Dallas, TX, USADepartment of Nutrition and Exercise Physiology, University of Missouri School of Medicine, Columbia, MO, USAIn mothers who are nursing their infants, increased clearance of plasma metabolites into the mammary gland may reduce ectopic lipid in the liver. No study to date has investigated the role of lactation on liver lipid synthesis in humans, and we hypothesized that lactation would modify fatty acid and glucose handling to support liver metabolism in a manner synchronized with the demands of milk production. Lactating (n = 18) and formula-feeding women (n = 10) underwent metabolic testing at 6-week postpartum to determine whether lactation modified intrahepatic triacylglycerols (IHTGs), measured by proton magnetic resonance spectroscopy. Subjects ingested oral deuterated water to measure fractional de novo lipogenesis (DNL) in VLDL-TG during fasting and during an isotope-labeled clamp at an insulin infusion rate of 10 mU/m2/min. Compared with formula-feeding women, we found that lactating women exhibited lower plasma VLDL-TG concentrations, similar IHTG content and similar contribution of DNL to total VLDL-TG production. These findings suggest that lactation lowers plasma VLDL-TG concentrations for reasons that are unrelated to IHTG and DNL. Surprisingly, we determined that the rate of appearance of nonesterified fatty acids was not related to IHTG in either group, and the expected positive association between DNL and IHTG was only significant in formula-feeding women. Further, in lactating women only, the higher the prolactin concentration, the lower the IHTG, while greater DNL strongly associated with elevations in VLDL-TG. In conclusion, we suggest that future studies should investigate the role of lactation and prolactin in liver lipid secretion and metabolism.http://www.sciencedirect.com/science/article/pii/S0022227522001213hormoneslipogenesisliver metabolismmammary glandnonesterified fatty acidspregnancy |
| spellingShingle | Maria A. Ramos-Roman Majid M. Syed-Abdul Brian M. Casey Jeffry R. Alger Yu-Lun Liu Elizabeth J. Parks Lactation alters the relationship between liver lipid synthesis and hepatic fat stores in the postpartum period Journal of Lipid Research hormones lipogenesis liver metabolism mammary gland nonesterified fatty acids pregnancy |
| title | Lactation alters the relationship between liver lipid synthesis and hepatic fat stores in the postpartum period |
| title_full | Lactation alters the relationship between liver lipid synthesis and hepatic fat stores in the postpartum period |
| title_fullStr | Lactation alters the relationship between liver lipid synthesis and hepatic fat stores in the postpartum period |
| title_full_unstemmed | Lactation alters the relationship between liver lipid synthesis and hepatic fat stores in the postpartum period |
| title_short | Lactation alters the relationship between liver lipid synthesis and hepatic fat stores in the postpartum period |
| title_sort | lactation alters the relationship between liver lipid synthesis and hepatic fat stores in the postpartum period |
| topic | hormones lipogenesis liver metabolism mammary gland nonesterified fatty acids pregnancy |
| url | http://www.sciencedirect.com/science/article/pii/S0022227522001213 |
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