1
|
Nerius L, Vogel M, Ceglarek U, Kiess W, Biemann R, Stepan H, Kratzsch J. Bone turnover in lactating and nonlactating women. Arch Gynecol Obstet 2023; 308:1853-1862. [PMID: 37707552 PMCID: PMC10579129 DOI: 10.1007/s00404-023-07189-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 08/07/2023] [Indexed: 09/15/2023]
Abstract
PURPOSE During lactation, bone turnover increases, reflecting the mobilization of Calcium from maternal skeletal stores and resulting in bone loss. However, mechanisms are not yet fully understood, and previous studies have been comparatively small. We aim to assess bone metabolism during lactation by comparing bone-metabolism-related-parameters between large cohorts of lactating and nonlactating women. METHODS In a retrospective cohort study, we recruited 779 postpartum women and 742 healthy, nonpregnant, nonlactating controls. Postpartum women were examined 3 and 6 months after delivery and retrospectively assigned to either the exclusively breastfeeding (exc-bf) group if they had exclusively breastfed or the nonexclusively breastfeeding (nonexc-bf) group if they had not exclusively breastfed up to the respective visit. Serum levels of PTH, Estradiol, total Calcium, Phosphate, and bone turnover markers (ßCTX, P1NP, Osteocalcin) were compared between the groups. RESULTS Bone turnover markers were significantly increased in exc-bf and nonexc-bf women compared with the controls (all ps < .001). ßCTX was approximately twice as high in exc-bf women than in the controls. PTH levels were marginally higher in exc-bf (p < .001) and nonexc-bf women (p = .003) compared with the controls (6 months). Estradiol was suppressed in exc-bf women compared with the controls (p < .001, 3 months). CONCLUSION Exc-bf and even nonexc-bf states are characterized by an increase in bone formation and resorption markers. The PTH data distribution of exc-bf, nonexc-bf, and control groups in the underpart of the reference range suggest that lactational bone loss is relatively independent of PTH.
Collapse
Affiliation(s)
- Lena Nerius
- LIFE Leipzig Research Center for Civilization Diseases, University of Leipzig, 04103, Leipzig, Germany
| | - Mandy Vogel
- LIFE Leipzig Research Center for Civilization Diseases, University of Leipzig, 04103, Leipzig, Germany
| | - Uta Ceglarek
- Institute for Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics (ILM), University of Leipzig, Paul-List-Str. 13-15, 04103, Leipzig, Germany
| | - Wieland Kiess
- LIFE Leipzig Research Center for Civilization Diseases, University of Leipzig, 04103, Leipzig, Germany
- Department of Women and Child Health, Hospital for Children and Adolescents and Center for Pediatric Research, University of Leipzig, 04103, Leipzig, Germany
| | - Ronald Biemann
- Institute for Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics (ILM), University of Leipzig, Paul-List-Str. 13-15, 04103, Leipzig, Germany
| | - Holger Stepan
- Department of Obstetrics, University of Leipzig, 04103, Leipzig, Germany
| | - Jürgen Kratzsch
- Institute for Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics (ILM), University of Leipzig, Paul-List-Str. 13-15, 04103, Leipzig, Germany.
| |
Collapse
|
2
|
Kovacs CS. Maternal Mineral and Bone Metabolism During Pregnancy, Lactation, and Post-Weaning Recovery. Physiol Rev 2016; 96:449-547. [PMID: 26887676 DOI: 10.1152/physrev.00027.2015] [Citation(s) in RCA: 251] [Impact Index Per Article: 31.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
During pregnancy and lactation, female physiology adapts to meet the added nutritional demands of fetuses and neonates. An average full-term fetus contains ∼30 g calcium, 20 g phosphorus, and 0.8 g magnesium. About 80% of mineral is accreted during the third trimester; calcium transfers at 300-350 mg/day during the final 6 wk. The neonate requires 200 mg calcium daily from milk during the first 6 mo, and 120 mg calcium from milk during the second 6 mo (additional calcium comes from solid foods). Calcium transfers can be more than double and triple these values, respectively, in women who nurse twins and triplets. About 25% of dietary calcium is normally absorbed in healthy adults. Average maternal calcium intakes in American and Canadian women are insufficient to meet the fetal and neonatal calcium requirements if normal efficiency of intestinal calcium absorption is relied upon. However, several adaptations are invoked to meet the fetal and neonatal demands for mineral without requiring increased intakes by the mother. During pregnancy the efficiency of intestinal calcium absorption doubles, whereas during lactation the maternal skeleton is resorbed to provide calcium for milk. This review addresses our current knowledge regarding maternal adaptations in mineral and skeletal homeostasis that occur during pregnancy, lactation, and post-weaning recovery. Also considered are the impacts that these adaptations have on biochemical and hormonal parameters of mineral homeostasis, the consequences for long-term skeletal health, and the presentation and management of disorders of mineral and bone metabolism.
Collapse
Affiliation(s)
- Christopher S Kovacs
- Faculty of Medicine-Endocrinology, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
| |
Collapse
|
3
|
Nordholm A, Rix M, Olgaard K, Lewin E. Parathyroid hormone-related peptide plasma concentrations in patients on hemodialysis. Scandinavian Journal of Clinical and Laboratory Investigation 2014; 74:206-12. [DOI: 10.3109/00365513.2013.876656] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
4
|
|
5
|
Wysolmerski JJ. Conversations between breast and bone: Physiological bone loss during lactation as evolutionary template for osteolysis in breast cancer and pathological bone loss after menopause. ACTA ACUST UNITED AC 2007. [DOI: 10.1138/20070268] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
6
|
Ardeshirpour L, Dann P, Adams DJ, Nelson T, VanHouten J, Horowitz MC, Wysolmerski JJ. Weaning triggers a decrease in receptor activator of nuclear factor-kappaB ligand expression, widespread osteoclast apoptosis, and rapid recovery of bone mass after lactation in mice. Endocrinology 2007; 148:3875-86. [PMID: 17495007 DOI: 10.1210/en.2006-1467] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A significant portion of milk calcium comes from the mother's skeleton, and lactation is characterized by rapid bone loss. The most remarkable aspect of this bone loss is its complete reversibility, and the time after weaning is the most rapid period of skeletal anabolism in adults. Despite this, little is known of the mechanisms by which the skeleton repairs itself after lactation. We examined changes in bone and calcium metabolism defining the transition from bone loss to bone recovery at weaning in mice. Bone mass decreases during lactation and recovers rapidly after weaning. Lactation causes changes in bone microarchitecture, including thinning and perforation of trabecular plates that are quickly repaired after weaning. Weaning causes a rapid decline in urinary C-telopeptide levels and stimulates an increase in circulating levels of osteocalcin. Bone histomorphometry documented a significant reduction in the numbers of osteoclasts on d 3 after weaning caused by a coordinated wave of osteoclast apoptosis beginning 48 h after pup removal. In contrast, osteoblast numbers and bone formation rates, which are elevated during lactation, remain so 3 d after weaning. The cessation of lactation stimulates an increase in circulating calcium levels and a reciprocal decrease in PTH levels. Finally, weaning is associated with a decrease in levels of receptor activator of nuclear factor-kappaB ligand mRNA in bone. In conclusion, during lactation, bone turnover is elevated, and bone loss is rapid. Weaning causes selective apoptosis of osteoclasts halting bone resorption. The sudden shift in bone turnover favoring bone formation subsequently contributes to the rapid recovery of bone mass.
Collapse
Affiliation(s)
- Laleh Ardeshirpour
- Section of Pediatric Endocrinology, Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut 06520-8020, USA
| | | | | | | | | | | | | |
Collapse
|
7
|
|
8
|
Abstract
Calcium is an important nutrient that is secreted into milk in quantities that put a considerable stress upon maternal calcium homeostasis. Here we summarize the evidence that two important entities, the extracellular calcium-sensing receptor (CaR) and parathyroid hormone-related protein (PTHrP) are involved in a feedback loop that regulates calcium fluxes to the mammary gland. The CaR may also play a role in regulating milk secretion, and may regulate the proliferation of normal and neoplastic mammary epithelial cells. Finally, the relationship between the CaR and PTHrP in breast cancer cells may promote the formation of osteolytic bone metastases.
Collapse
Affiliation(s)
- Joshua N VanHouten
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Yale University School of Medicine, TAC S120, New Haven, Connecticut, 06520, USA.
| |
Collapse
|
9
|
VanHouten JN, Dann P, Stewart AF, Watson CJ, Pollak M, Karaplis AC, Wysolmerski JJ. Mammary-specific deletion of parathyroid hormone-related protein preserves bone mass during lactation. J Clin Invest 2003; 112:1429-36. [PMID: 14597768 PMCID: PMC228471 DOI: 10.1172/jci19504] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Large amounts of calcium are transferred to offspring by milk. This demand results in negative calcium balance in lactating mothers and is associated with rapid bone loss. The mechanisms of bone loss during lactation are only partly understood. Several studies have suggested that parathyroid hormone-related protein (PTHrP) might be secreted into the circulation by the lactating mammary gland and regulate bone turnover during lactation. Because mammary development fails in the absence of PTHrP, conventional PTHrP knockout mice cannot be used to address this possibility. To examine this hypothesis, we therefore used mice carrying a beta-lactoglobulin promoter-driven Cre transgene, one null PTHrP allele, and one floxed PTHrP allele. Expression of Cre specifically in mammary epithelial cells during late pregnancy and lactation resulted in efficient deletion of the PTHrP gene; mammary gland PTHrP mRNA and milk PTHrP protein were almost completely absent. Removal of PTHrP from the lactating mammary glands resulted in reductions in levels of circulating PTHrP and 1,25-dihydroxy vitamin D and urinary cAMP. In addition, bone turnover was reduced and bone loss during lactation was attenuated. We conclude that during lactation mammary epithelial cells are a source of circulating PTHrP that promotes bone loss by increasing rates of bone resorption.
Collapse
Affiliation(s)
- Joshua N VanHouten
- Section of Endocrinology and Metabolism, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut 06520-8020, USA
| | | | | | | | | | | | | |
Collapse
|
10
|
VanHouten JN, Dann P, Stewart AF, Watson CJ, Pollak M, Karaplis AC, Wysolmerski JJ. Mammary-specific deletion of parathyroid hormone–related protein preserves bone mass during lactation. J Clin Invest 2003. [DOI: 10.1172/jci200319504] [Citation(s) in RCA: 138] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
|
11
|
Durst R, Meirovitz A, Gross D, Kolker O, Muszkat M. Post-partum hypocalcemia: idiopatic hypoparathyroidism manifested early in lactation. J Endocrinol Invest 2002; 25:561-3. [PMID: 12109630 DOI: 10.1007/bf03345501] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Hypocalcemia associated with labor and lactation is a rare condition reported previously in patients with hypovitaminosis D. We here describe a case of a young woman in whom symptomatic severe hypocalcemia appeared after her second delivery, early in lactation. At the end of lactation the condition worsened. We review all previously reported cases and suggest a possible physiologic explanation for the association between pregnancy, lactation and the appearance of symptomatic hypocalcemia.
Collapse
Affiliation(s)
- R Durst
- Department of Medicine, Hadassah Medical Center and Hebrew University Medical School, Jerusalem, Israel.
| | | | | | | | | |
Collapse
|
12
|
de Toro Salas A, Dueñas Díez J, de Jaime Revuelta E. Concentraciones de calcio y de marcadores de remodelamiento óseo en sangre de cordón umbilical y en orina del recién nacido en el parto. An Pediatr (Barc) 2001. [DOI: 10.1016/s1695-4033(01)77528-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
|
13
|
Haenel LC, Mayfield RK. Primary hyperparathyroidism in a twin pregnancy and review of fetal/maternal calcium homeostasis. Am J Med Sci 2000; 319:191-4. [PMID: 10746832 DOI: 10.1097/00000441-200003000-00011] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Hyperparathyroidism occurs rarely in pregnancy; this is the first reported case in a twin gestation. Management of this unusual case is described and an overview of fetal/maternal calcium homeostasis is discussed. METHODS The patient presented at 33 weeks' gestation with hypertension and premature labor. Serum calcium and phosphorus were 14.6 and 1.7 mg/dL, respectively. An intact parathyroid hormone (PTH) level was 243 pg/mL (normal, 10-65). RESULTS The patient was treated with parenteral saline hydration and oral phosphate supplementation that was continued through week 37. Although the calcium remained elevated between 12.6 and 13.3 mg/dL, medical therapy was continued because of the risks of surgery in the third trimester. Alternative medical treatments (bisphosphonates, calcitonin) were considered ill advised in pregnancy. The patient remained asymptomatic without further labor, and at week 37, fraternal twins were delivered by cesarean section. The infants were monitored closely and experienced no hypocalcemic symptoms after delivery. Postpartum, the mother's parathyroid scan and ultrasound were negative. She underwent neck exploration and a single 700-mg adenoma was removed. Transient asymptomatic hypocalcemia (7.5 mg/dL) occurred postoperatively, and she was placed on oral calcium (1500 mg/day) and calcitriol (0.25 mg/day). These were stopped at 8 weeks, when both PTH and parathyroid hormone-related peptide levels were normal. CONCLUSION Mother and infants continue to do well after 18 months. This case provides an interesting setting to consider the interrelationships between elevated maternal PTH and the fetal/placental factors that regulate calcium metabolism in pregnancy.
Collapse
Affiliation(s)
- L C Haenel
- Medical University of South Carolina, Division of Endocrinology, Diabetes, and Medical Genetics, Charleston 29425, USA
| | | |
Collapse
|
14
|
Primary Hyperparathyroidism In a Twin Pregnancy and Review of Fetal/Maternal Calcium Homeostasis. Am J Med Sci 2000. [DOI: 10.1016/s0002-9629(15)40720-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
15
|
Curtis NE, King RG, Moseley JM, Ho PW, Rice GE, Wlodek ME. Intrauterine expression of parathyroid hormone-related protein in normal and pre-eclamptic pregnancies. Placenta 1998; 19:595-601. [PMID: 9859863 DOI: 10.1016/s0143-4004(98)90020-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Maternal hypertension, vasoconstriction and placental insufficiency are features of pre-eclampsia. Alterations in calcium homeostasis and in the production of calciotropic hormones and vasoactive agents have also been described in association with pre-eclampsia. Parathyroid hormone-related protein (PTHrP) is abundantly expressed in intrauterine tissues during normal pregnancy and has roles in fetal growth and calcium homeostasis, placental calcium transport and vascular tone regulation. Intrauterine PTHrP mRNA expression and tissue PTHrP content were determined by Northern blot analysis and radio-immunoassay, respectively, in preterm and term pre-eclamptic women. PTHrP mRNA expression and PTHrP content in placenta, amnion over placenta, reflected amnion and choriodecidua from preterm pre-eclamptic women (n=8-10) were not different from preterm controls (n= 10-12). PTHrP mRNA expression and content in amnion over placenta and reflected amnion were significantly greater in term compared to preterm pre-eclamptics (P<0.05). PTHrP mRNA expression was significantly lower in choriodecidua from term pre-eclamptic women (n=8) compared to term controls (n=28, P<0.05), but was not different in placenta or amnion. PTHrP content was not altered in term pre-eclamptic women (n=8) compared to controls (n=25) for any tissue. In summary, PTHrP expression in placenta and amnion was not increased in pre-eclamptic women in association with maternal hypertension, placental insufficiency and vasoconstriction. PTHrP mRNA expression was decreased in choriodecidua in association with term but not preterm pre-eclampsia, however, levels of the protein were not decreased. The data suggest that PTHrP is not involved in the placental pathophysiology of pre-eclampsia in late gestation.
Collapse
Affiliation(s)
- N E Curtis
- Department of Perinatal Medicine, Royal Women's Hospital, Carlton, Victoria, Australia
| | | | | | | | | | | |
Collapse
|
16
|
Lippuner K, Zehnder HJ, Casez JP, Takkinen R, Jaeger P. PTH-related protein is released into the mother's bloodstream during lactation: evidence for beneficial effects on maternal calcium-phosphate metabolism. J Bone Miner Res 1996; 11:1394-9. [PMID: 8889837 DOI: 10.1002/jbmr.5650111004] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Recent studies have indicated that parathyroid hormone-related protein (PTHrP) may have important actions in lactation, affecting the mammary gland, and also calcium metabolism in the newborn and the mother. However, there are as yet no longitudinal studies to support the notion of an endocrine role of this peptide during nursing. We studied a group of 12 nursing mothers, mean age 32 years, after they had been nursing for an average of 7 weeks (B) and also 4 months after stopping nursing (A). It was assumed that changes occurring between A and B correspond to the effect of lactation. Blood was assayed for prolactin (PRL), PTHrP (two-site immunoradiometric assay with sheep antibody against PTHrP(1-40), and goat antibody against PTHrP(60-72), detection limit 0.3 pmol/l), intact PTH (iPTH), ionized calcium (Ca2+), 25-hydroxyvitamin D3 (25(OH)D3) and 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), alkaline phosphatase (alkP), as well as for creatinine (Cr), protein, phosphorus (P), and total calcium (Ca). Fasting 2-h urine samples were analyzed for Ca excretion (CaE) and renal phosphate threshold (TmP/GFR). PRL was significantly higher during lactation than after weaning (39 +/- 10 vs. 13 +/- 9 micrograms/l; p = 0.018) and so was PTHrP (2.8 +/- 0.35 vs. 0.52 +/- 0.04 pmol/l; p = 0.002), values during lactation being above the normal limit (1.3 pmol/l) in all 12 mothers. There was a significant correlation between PRL and PTHrP during lactation (r = 0.8, p = 0.002). Whole blood Ca2+ did not significantly change from A (1.20 +/- 0.02 mmol/l) to B (1.22 +/- 0.02, mmol/l), whereas total Ca corrected for protein (2.18 +/- 0.02 mmol/l) or uncorrected (2.18 +/- 0.02 mmol/l) significantly rose during lactation (2.31 +/- 0.02 mmol/l, p = 0.003 and 2.37 +/- 0.03 mmol/l, p = 0.002, respectively). Conversely, iPTH decreased during lactation (3.47 +/- 0.38 vs. 2.11 +/- 0.35 pmol/l, A vs. B, p = 0.02). Serum-levels of 25(OH)D3 and 1,25(OH)2D3 did not significantly change from A to B (23 +/- 2.3 vs. 24 +/- 1.9 ng/ml and 29.5 +/- 6.0 vs. 21.9 +/- 1.8 pg/ml, respectively). Both TmP/GFR and P were higher during lactation than after weaning (1.15 +/- 0.03 vs. 0.86 +/- 0.05 mmol/l GF, p = 0.003 and 1.25 +/- 0.03 vs. 0.96 +/- 0.05 mmol/l, p = 0.002, respectively) as was alkP (74.0 +/- 7.1 vs. 52.6 +/- 6.9 U/l, p = 0.003). CaE did not differ between A and B (0.015 +/- 0.003 vs. 0.017 +/- 0.003 mmol/l GF, A vs. B, NS). We conclude that lactation is accompanied by an increase in serum PRL. This is associated with a release of PTHrP into the maternal blood circulation. A rise in total plasma Ca ensues, probably in part by increased bone turnover as suggested by the elevation of alkP. PTH secretion falls, with a subsequent rise of TmP/GFR and plasma P despite high plasma levels of PTHrP.
Collapse
Affiliation(s)
- K Lippuner
- Policlinic of Medicine, University Hospital, Berne, Switzerland
| | | | | | | | | |
Collapse
|
17
|
Abstract
Osteoporosis has long been described in pregnant women who developed vertebral fractures in the last trimester or shortly after delivery without underlying disorders. However, this condition appears to be relatively rare and the clinical features, associated metabolic abnormalities and a pathological mechanism have not been fully established. This paper reviews available data on osteoporosis and pregnancy and briefly discusses the relationship between pregnancy and bone mass, calcium homeostasis, systemic skeletal hormones and local factors to help explain the pathophysiology of this unique disorder.
Collapse
Affiliation(s)
- W Khovidhunkit
- Department of Medicine, Albert Einstein Medical Center, Philadelphia, Pennsylvania 19141, USA
| | | |
Collapse
|