PMID- 36322718 OWN - NLM STAT- MEDLINE DCOM- 20221104 LR - 20230810 IS - 1091-6490 (Electronic) IS - 0027-8424 (Print) IS - 0027-8424 (Linking) VI - 119 IP - 45 DP - 2022 Nov 8 TI - A specialized metabolic pathway partitions citrate in hydroxyapatite to impact mineralization of bones and teeth. PG - e2212178119 LID - 10.1073/pnas.2212178119 [doi] LID - e2212178119 AB - Citrate is a critical metabolic substrate and key regulator of energy metabolism in mammalian cells. It has been known for decades that the skeleton contains most (>85%) of the body's citrate, but the question of why and how this metabolite should be partitioned in bone has received singularly little attention. Here, we show that osteoblasts use a specialized metabolic pathway to regulate uptake, endogenous production, and the deposition of citrate into bone. Osteoblasts express high levels of the membranous Na(+)-dependent citrate transporter solute carrier family 13 member 5 (Slc13a5) gene. Inhibition or genetic disruption of Slc13a5 reduced osteogenic citrate uptake and disrupted mineral nodule formation. Bones from mice lacking Slc13a5 globally, or selectively in osteoblasts, showed equivalent reductions in cortical thickness, with similarly compromised mechanical strength. Surprisingly, citrate content in mineral from Slc13a5(-/-) osteoblasts was increased fourfold relative to controls, suggesting the engagement of compensatory mechanisms to augment endogenous citrate production. Indeed, through the coordinated functioning of the apical membrane citrate transporter SLC13A5 and a mitochondrial zinc transporter protein (ZIP1; encoded by Slc39a1), a mediator of citrate efflux from the tricarboxylic acid cycle, SLC13A5 mediates citrate entry from blood and its activity exerts homeostatic control of cytoplasmic citrate. Intriguingly, Slc13a5-deficient mice also exhibited defective tooth enamel and dentin formation, a clinical feature, which we show is recapitulated in primary teeth from children with SLC13A5 mutations. Together, our results reveal the components of an osteoblast metabolic pathway, which affects bone strength by regulating citrate deposition into mineral hydroxyapatite. FAU - Dirckx, Naomi AU - Dirckx N AUID- ORCID: 0000-0001-6507-8106 AD - Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21205. AD - Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD 21201. FAU - Zhang, Qian AU - Zhang Q AD - Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21205. AD - Department of Nutrition and Health, China Agricultural University, Beijing 100193, China. FAU - Chu, Emily Y AU - Chu EY AD - Department of General Dentistry, Operative Division, University of Maryland School of Dentistry, Baltimore, MD 21201. AD - National Institute of Arthritis and Musculoskeletal and Skin Diseases, NIH, Bethesda, MD 20892. FAU - Tower, Robert J AU - Tower RJ AUID- ORCID: 0000-0001-5856-5758 AD - Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21205. AD - Department of Surgery, University of Texas Southwestern Medical Center, Dallas, TX 75390. FAU - Li, Zhu AU - Li Z AD - Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21205. AD - Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD 21201. FAU - Guo, Shenghao AU - Guo S AUID- ORCID: 0000-0002-3032-2153 AD - Department of Biomedical Engineering, Johns Hopkins University Whiting School of Engineering, Baltimore, MD 21218. FAU - Yuan, Shichen AU - Yuan S AD - Department of Chemistry, Brandeis University, Waltham, MA 02453. FAU - Khare, Pratik A AU - Khare PA AD - Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD 21218. FAU - Zhang, Cissy AU - Zhang C AD - Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD 21287. FAU - Verardo, Angela AU - Verardo A AUID- ORCID: 0000-0002-0203-279X AD - Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21205. FAU - Alejandro, Lucy O AU - Alejandro LO AD - National Institute of Arthritis and Musculoskeletal and Skin Diseases, NIH, Bethesda, MD 20892. FAU - Park, Angelina AU - Park A AUID- ORCID: 0000-0001-9470-660X AD - Department of General Dentistry, Operative Division, University of Maryland School of Dentistry, Baltimore, MD 21201. FAU - Faugere, Marie-Claude AU - Faugere MC AD - Department of Medicine, University of Kentucky, Lexington, KY 40506. FAU - Helfand, Stephen L AU - Helfand SL AD - Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI 02906. FAU - Somerman, Martha J AU - Somerman MJ AUID- ORCID: 0000-0002-4819-6079 AD - National Institute of Arthritis and Musculoskeletal and Skin Diseases, NIH, Bethesda, MD 20892. FAU - Riddle, Ryan C AU - Riddle RC AD - Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21205. AD - Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD 21201. AD - Research and Development Service, The Baltimore Veterans Administration Medical Center, Baltimore, MD 21201. FAU - de Cabo, Rafael AU - de Cabo R AUID- ORCID: 0000-0003-2830-5693 AD - Translational Gerontology Branch, National Institute on Aging, NIH, Baltimore, MD 21224. FAU - Le, Anne AU - Le A AD - Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD 21218. AD - Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD 21287. AD - Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21231. FAU - Schmidt-Rohr, Klaus AU - Schmidt-Rohr K AUID- ORCID: 0000-0002-3188-4828 AD - Department of Chemistry, Brandeis University, Waltham, MA 02453. FAU - Clemens, Thomas L AU - Clemens TL AD - Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21205. AD - Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD 21201. AD - Research and Development Service, The Baltimore Veterans Administration Medical Center, Baltimore, MD 21201. LA - eng GR - IK6 BX004984/BX/BLRD VA/United States GR - K99 AR079558/AR/NIAMS NIH HHS/United States GR - R01 DK099134/DK/NIDDK NIH HHS/United States GR - R24 ES028531/ES/NIEHS NIH HHS/United States PT - Journal Article PT - Research Support, N.I.H., Extramural PT - Research Support, N.I.H., Intramural PT - Research Support, Non-U.S. Gov't PT - Research Support, U.S. Gov't, Non-P.H.S. DEP - 20221102 PL - United States TA - Proc Natl Acad Sci U S A JT - Proceedings of the National Academy of Sciences of the United States of America JID - 7505876 RN - 2968PHW8QP (Citric Acid) RN - 0 (Symporters) RN - 91D9GV0Z28 (Durapatite) RN - 0 (Citrates) RN - 0 (Slc13a5 protein, mouse) RN - 0 (Dicarboxylic Acid Transporters) SB - IM MH - Animals MH - Mice MH - *Citric Acid/metabolism MH - *Symporters/metabolism MH - Durapatite/metabolism MH - Citrates MH - Citric Acid Cycle MH - Osteoblasts/metabolism MH - Mammals/metabolism MH - Dicarboxylic Acid Transporters/metabolism PMC - PMC9659386 OTO - NOTNLM OT - Slc13a5 OT - citrate OT - metabolism OT - mineralization OT - osteoblasts COIS- The authors declare no competing interest. EDAT- 2022/11/03 06:00 MHDA- 2022/11/05 06:00 PMCR- 2023/05/02 CRDT- 2022/11/02 15:03 PHST- 2022/11/02 15:03 [entrez] PHST- 2022/11/03 06:00 [pubmed] PHST- 2022/11/05 06:00 [medline] PHST- 2023/05/02 00:00 [pmc-release] AID - 202212178 [pii] AID - 10.1073/pnas.2212178119 [doi] PST - ppublish SO - Proc Natl Acad Sci U S A. 2022 Nov 8;119(45):e2212178119. doi: 10.1073/pnas.2212178119. Epub 2022 Nov 2.