Donate Help Contact The AHA Sign In Home
American Heart Association
Arteriosclerosis, Thrombosis, and Vascular Biology
Search: search_blue_button Advanced Search
Arteriosclerosis, Thrombosis, and Vascular Biology. 2000;20:2346-2348

This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Parhami, F.
Right arrow Articles by Demer, L. L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Parhami, F.
Right arrow Articles by Demer, L. L.
Right arrowPubmed/NCBI databases
*Substance via MeSH
Medline Plus Health Information
*Osteoporosis
(Arteriosclerosis, Thrombosis, and Vascular Biology. 2000;20:2346.)
© 2000 American Heart Association, Inc.


Special Article

Role of Lipids in Osteoporosis

Farhad Parhami; Alan Garfinkel; Linda L. Demer

From the Division of Cardiology, Department of Medicine (F.P., L.L.D., A.G.), Physiological Science (A.G), and Physiology (L.L.D.), UCLA School of Medicine, Los Angeles, Calif.

Correspondence to Linda L. Demer, MD, PhD, Chief, Division of Cardiology, 10833 Le Conte Avenue, Center for the Health Sciences 47-123, Los Angeles, CA 90095-1679. E-mail ldemer{at}mednet.ucla.edu

Abstract

Abstract—Cardiovascular disease and osteoporosis together account for most of the morbidity and mortality in our aging population despite significant improvements in treatment. Recently, converging lines of evidence suggest that these 2 diseases share an etiologic factor –that hyperlipidemia contributes not only to atherosclerotic plaque formation, but also to osteoporosis, following a similar biologic mechanism involving lipid oxidation. In vitro studies indicate that lipid products of oxidation promote osteoblastic differentiation of vascular cells and inhibit such differentiation in bone cells. Ex vivo, in vivo, and clinical studies further suggest that lipid-lowering agents reduce both atherosclerotic calcification and osteoporosis. Whether lipid-lowering agents reduce osteoporosis directly or indirectly through lipid reduction remains controversial.


Key Words: atherosclerosis • osteoporosis • calcification

Growing evidence links vascular and bone disease. Osteoporosis is associated with both atherosclerosis and vascular calcification.1 2 3 4 5 6 7 8 9 Although this association is often dismissed as a consequence of aging, the relationship remains significant after age adjustment in some1 9 but not all10 studies. Osteoporotic postmenopausal women are at significantly greater risk for cardiovascular disease than age-matched controls.11 Patients with lower bone density and osteoporosis also have higher lipid levels, more severe coronary atherosclerosis, and have a greater risk of stroke death.2 3 12 13 14 15 The common finding of simultaneous vascular calcification and osteoporosis in individual patients suggests that local tissue factors govern regulation of biomineralization.

Bone and vascular tissue share several features at the molecular and cellular levels. Bone and marrow both contain endothelial cells, preosteoblasts, and monocyte-derived osteoclasts, all of which have counterparts in the artery wall. Both bone and atherosclerotic arteries contain osteopontin, bone morphogenetic protein, matrix Gla protein, collagen I, osteonectin, osteocalcin, nitric oxide, and matrix vesicles. Atherosclerosis and osteoporosis both involve recruitment and differentiation of monocytic cells that differentiate into macrophage-foam cells in artery and osteoclasts in bone. Each cylindrical unit of bone, the osteon, contains a central vessel lined with endothelial cells and a subendothelial matrix. Osteoblast progenitor cells are located immediately outside this matrix.

The artery wall contains cells capable of differentiation into osteoblasts, following the same stages of differentiation as occur in bone-derived osteoblasts, and ultimately producing bone mineral.16 The same oxidized lipids that induce atherosclerosis also induce mineralization and differentiation of the osteoblastic cells in the artery wall.16 Consistent with this finding, hyperlipidemia is associated with vascular calcification in mice.17 However, in bone and bone osteoblasts, osteoblastic differentiation is inhibited by oxidized lipids and hyperlipidemia.16 18

Lipids have been shown to accumulate in bones of mice and around bone vessels in patients with osteoporosis.19 20 Because the immature osteoblasts are located immediately adjacent to the subendothelial matrix of bone vessels, lipid accumulation in subendothelial matrix would be expected to inhibit differentiation of the bone-forming cells. In addition, because oxidized lipids induce endothelial expression of monocyte chemotactic factors and M-CSF, a potent inducer of osteoclastic differentiation, oxidized lipids would be expected to promote bone resorption by recruitment and differentiation of osteoclast precursor cells. Consistent with this possibility, high-fat diet inhibits bone growth in chickens and the effect is reversed by antioxidants.21

Clinical studies also support a role for lipids in both vascular calcification and osteoporosis. Lipid-lowering agents reduce coronary vascular calcification in patients, where the degree of improvement follows in direct relation to the degree of lipid lowering.22 Lipid-lowering agents also enhance bone mineralization in rodents23 and patients24 and may reduce osteoporotic fractures in patients.25 26 27 These effects on bone were originally attributed to a direct effect of the specific class of lipid-lowering agents used, HMG-CoA reductase inhibitors (statins).

It is possible that statins may directly protect bone. However, it is extremely difficult to dissect out the effects of statins versus effects of lipid lowering. In whole organisms, including rodents,28 statins strongly induce lipid clearance, thus lowering lipid levels. Therefore, from these clinical studies, it is not possible to distinguish whether the improvement in bone density and reduction in fracture risk are due to lipid lowering or to a direct effect of statins.

A direct effect was inferred from ex vivo studies showing histologic growth following direct injection into bone organ culture and in vitro studies showing BMP-2 induction by lovastatin in a bone cell line culture.23 However, in whole organisms, statins are nearly completely cleared by the first pass through the liver. In addition, it is not clear how inhibitors of cholesterol biosynthesis influence BMP-2 expression. A key activator of BMP-2, hedgehog,29 actually requires covalent binding to cholesterol for its activity.30 Thus, in blocking the cholesterol biosynthetic pathway, statins would be expected to reduce BMP-2 expression.

The 3 observational studies that show reduced fractures in patients taking HMG-CoA reductase inhibitors reported less effect25 26 or no effect27 of other classes of lipid-lowering agents. The reduced effect is consistent with an indirect effect that depends on the degree of lipid lowering, because non-statin lipid-lowering agents are well-known to lower lipids less effectively than statins. The apparent absence of effect of non-statin agents reported by Chan et al27 is actually entirely attributable to the small number of fracture patients using non-statins (n=6). Based on chi-square simulation analysis, this study had a power of less than 30% for detecting an effect of non-statin drugs equal to that of statins (halving fractures), ie, it had a 70% chance of failing to achieve statistical significance in the association between non-statins and fractures, even if the non-statins had actually reduced fractures 2-fold, simply because of the small sample size. Thus, as above, none of these clinical studies is able to distinguish whether fracture reduction is attributable to lipid lowering or to a direct effect of statins.

Earlier animal studies showed that lipid lowering by non-statins alleviated steroid-induced osteoporosis to the same degree as statins.31 It is notable that bisphosphonates, leading agents for osteoporosis, also reduce LDL and increase HDL levels in humans.32 They also reduce atherosclerosis in rabbits, raising the question of whether some of their effects on bone may be through lipid lowering.33 Another widely-used treatment for osteoporosis, hormone replacement therapy, also lowers lipid levels. These data support the concept that lipids contribute to both vascular calcification and osteoporosis.

The concept that a single factor could promote mineralization in one tissue while inhibiting it in another has biologic precedent. In chronic infection, inflammation, or foreign body reaction, a common response of soft tissue is mineralization (eg, vertebral osteophytes, liver parasites, surgical sponges), whereas bone tissue responds with demineralization (eg, osteomyelitis, lytic periodontitis). If oxidized lipids in artery and bone mimic refractory infection or foreign material, then vascular calcification and osteoporosis would be an expected consequence.

In summary, recent research suggests that cardiovascular disease and bone loss are functionally interwoven. Osteopenia and osteoporosis correlate positively with atherosclerosis, vascular calcification, and cardiovascular events, with some evidence for age-independence. Lipid oxidation products that promote atherogenesis also inhibit osteoblast differentiation, but they also promote mineral formation by vascular cells. Lipid-lowering agents reduce atherosclerosis, vascular calcification, and osteoporotic fractures. The reduction in vascular calcification is directly related to the degree of lipid lowering. It is not known whether the reduction in fractures is related to the degree of lipid lowering and whether the effect is limited to 1 class of lipid-lowering agents, the HMG-CoA reductase inhibitors. Future studies are needed to determine whether degree and duration of hyperlipidemia correlate with osteopenia in humans; whether experimental hyperlipidemia affects bone density in animals; and whether the degree of lipid lowering determines the degree of reduction in osteoporosis. Randomized trials with adequate power are needed to compare bone density and fracture in individuals randomized to statin versus other lipid-lowering agents and paired to match equal degrees of lipid lowering.

A critical priority is to determine whether treatments for osteoporosis aggravate or benefit vascular calcification and vice versa. The fundamental mechanisms by which lipids modulate differentiation of mineralizing cells and biomineralization must be evaluated, and known mechanisms by which lipids regulate atherogenesis offer a valuable starting point. Existing and exciting new animal models offer promise in identifying genetic regulatory factors.17 34 35 36 37 Other research priorities at the interface between bone and vascular biology have been named by a recent NIH Working Group.38 Ultimately, this research should lead to new and efficient strategies for simultaneous biologic reversal of both vascular calcification and osteoporosis.

Acknowledgments

This work was supported in part by NHLBI grant 30568 and the Cummins and Cohen Memorial Funds.

Received March 17, 2000; accepted August 25, 2000.

References

  1. Boukhris R, Becker KL. Calcification of the aorta and osteoporosis. JAMA. 1972;219:1307–1311.[Medline] [Order article via Infotrieve]
  2. Broulik PD, Kapitola J. Interrelations between body weight, cigarette smoking and spine mineral density in osteoporotic Czech women. Endoc Reg. 1993;2:57–60.
  3. Laroche M, Pouilles JM, Ribot C, Bendayan P, Bernard J, Boccalon H, Mazieres B. Comparison of the bone mineral content of the lower limbs in men with ischaemic atherosclerotic disease. Clin Rheumatol. 1994;13:61–64.
  4. Marum GJ. Roentgenographic observations in age atrophy and osteoporosis of the spine. Radiology. 1946;46:220–226.
  5. Sugihara N, Matsuzaki M. The influence of severe bone loss on mitral annular calcification in postmenopausal osteoporosis of elderly Japanese women. Jpn Cir J. 1993;57:14–26.
  6. Ouchi Y, Akishita M, de Souza AC, Nakamura T, Orimo H. Age-related loss of bone mass and aortic/aortic valve calcification: reevaluation of recommended dietary allowance of calcium in the elderly. Ann New York Acad Sci. 1993;676:297–307.[Medline] [Order article via Infotrieve]
  7. Banks LM, Lees B, MacSweeney JE, Stevenson JC. Effect of degenerative spinal and aortic calcification on bone density measurements in post-menopausal women: links between osteoporosis and cardiovascular disease? Euro J Clin Invest. 1994;12:813–817.
  8. Dent CE, Engelbrecht HE, Godfrey RC. Osteoporosis of lumbar vertebrae and calcification of abdominal aorta in women living in Durban. BMJ. 1968;4:76–79.
  9. Jie KG, Bots ML, Vermeer C, Witteman JC, Grobbee DE. Vitamin K status and bone mass in women with and without aortic atherosclerosis: a population-based study. Calcif Tissue Int. 1996;59:352–356.[Medline] [Order article via Infotrieve]
  10. Vogt MT, San Valentin R, Forrest KY, Nevitt MC, Cauley JA. Bone mineral density and aortic calcification: the Study of Osteoporotic Fractures. J Am Geri Soc. 1997;45:140–145.
  11. von der Recke P, Hansen MA, Hassager C. The association between low bone mass at the menopause and cardiovascular mortality. Am J Med. 1999;106:273–278.[Medline] [Order article via Infotrieve]
  12. Barengolts EI, Berman M, Kukreja SC, Kouznetsova T, Lin C, Chomka EV. Osteoporosis and coronary atherosclerosis in asymptomatic postmenopausal women. Calcif Tissue Int. 1998;62:209–213.[Medline] [Order article via Infotrieve]
  13. Browner WS, Seeley DF, Vogt TM, Cummings SR. Non-trauma mortality in elderly women with low bone mineral density. Study of Osteoporotic Fractures Research Group. Lancet. 1991;338:355–358.[Medline] [Order article via Infotrieve]
  14. Uyama O, Yoshimoto Y, Yamamoto Y, Kawai A. Bone changes and carotid atherosclerosis in postmenopausal women. Stroke. 1997;28:1730–1732.[Abstract/Free Full Text]
  15. Pinals RS, Jabbs JM. Type-IV hyperlipoproteinaemia and transient osteoporosis. Lancet. 1972;2:929.
  16. Parhami F, Morrow AD, Balucan J, Leitinger N, Watson AD, Tintut Y, Berliner JA, Demer LL. Lipid oxidation products have opposite effects on calcifying vascular cell and bone cell differentiation. A possible explanation for the paradox of arterial calcification in osteoporotic patients. Arterio Thromb Vasc Biol. 1997;17:680–687.[Abstract/Free Full Text]
  17. Towler DA, Bidder M, Latifi T, Coleman T, Semenkovich CF. Diet-induced diabetes activates an osteogenic gene regulatory program in the aortas of low density lipoprotein receptor-deficient mice. J Biol Chem. 1998;273:30427–30434.[Abstract/Free Full Text]
  18. Parhami F, Jackson SM, Le V, Balucan JP, Tintut Y, Territo M, Demer LL. Atherogenic diet and minimally oxidized low density lipoprotein inhibit osteogenic and promote adipogenic differentiation of marrow stromal cells. J Bone Min Res. 1999;14:2067–2078.[Medline] [Order article via Infotrieve]
  19. Rajendran KG, Chen SY, Sood A, Spielvogel BF, Hall IH. The anti-osteoporotic activity of amine-carboxyboranes in rodents. Biomed Pharmacother. 1995;49:131–140.[Medline] [Order article via Infotrieve]
  20. Ramseier E. Untersuchungen uber arteriosklerotische Veranderungen der Knochenarterien. Virchows Arch path. Anat. 1962;336:77–86.
  21. Xu H, Watkins BA, Seifert MF. Vitamin E stimulates trabecular bone formation and alters epiphyseal cartilage morphometry. Calcif Tissue Int. 1995;57:293–300.[Medline] [Order article via Infotrieve]
  22. Callister TQ, Raggi P, Cooil B, Lippolis NJ, Russo DJ. Effect of HMG-CoA reductase inhibitors on coronary artery disease as assessed by electron-beam computed tomography. N Engl J Med. 1998;339:1972–1978.[Abstract/Free Full Text]
  23. Mundy G, Garrett R, Harris S, Chan J, Chen D, Rossini G, Boyce B, Zhao M, Gutierrez G. Stimulation of bone formation in vitro and in rodents by statins. Science. 1999;286:1946–1949.[Abstract/Free Full Text]
  24. Edwards CJ, Hart DJ, Spector TD. Oral statins and increased bone-mineral density in postmenopausal women. Lancet. 2000;355:2218–2219.[Medline] [Order article via Infotrieve]
  25. Meier CR, Schlienger RG, Kraenzlin ME, Schlegel B, Jick H. HMG-CoA reductase inhibitors and the risk of fractures. JAMA. 2000;283:3205–3210.[Abstract/Free Full Text]
  26. Wang PS, Solomon DH, Mogun H, Avorn J. HMG-CoA reductase inhibitors and the risk of hip fractures in elderly patients. JAMA. 2000;283:3211–3216.[Abstract/Free Full Text]
  27. Chan KA, Andrade SE, Boles M, Buist DSM, Chase GA, Donahue JG, Goodman MJ, Gurwitz JH, LaCroix AZ, Platt R. Inhibitors of hydroxymethylglutaryl-coenzyme A reductase and risk of fracture among older women. Lancet. 2000;355:2185–2188.[Medline] [Order article via Infotrieve]
  28. Koga T, Kikuchi T, Miyazaki A, Koike H. Tissue–selective inhibition of sterol synthesis in mice by pravastatin sodium after a single or repeated oral administration. Lipids. 1995;30:775–779.[Medline] [Order article via Infotrieve]
  29. Vortkamp A, Lee K, Lanske B, Segre GV, Kronenberg HM, Tabin CJ. Regulation of rate of cartilage differentiation by Indian hedgehog and PTH-related protein. Science. 1996;273:613–621.[Abstract]
  30. Porter JA, Young KE, Beachy PA. Cholesterol modification of hedgehog signaling proteins in animal development. Science. 1996;274:255–259.[Abstract/Free Full Text]
  31. Wang GJ, Chung KC, Shen WJ. Lipid clearing agents in steroid-induced osteoporosis. J Formos Med Assoc. 1995;94:589–592.[Medline] [Order article via Infotrieve]
  32. Adami S, Braga V, Guidi G, Gatti D, Gerardi DA, Fracassi E. Chronic intravenous aminobisphosphonate therapy increases high-density lipoprotein cholesterol and decreases low-density lipoprotein cholesterol. J Bone Min Res. 2000;15:599–604.
  33. Kramsch DM, Aspen AJ, Rozler LJ. Atherosclerosis: prevention by agents not affecting abnormal levels of blood lipids. Science. 1981;213:1511–1512.[Free Full Text]
  34. Bell FP, Gerrity RG. Evidence for an altered lipid metabolic state in circulating blood monocytes under conditions of hyperlipemia in swine and its implications in arterial lipid metabolism. Arterioscler Thromb. 1992;12:155–162.[Abstract/Free Full Text]
  35. Demer LL. Effect of calcification on in vivo mechanical response of rabbit arteries to balloon dilatation. Circulation. 1991;83:2083–2093.[Abstract/Free Full Text]
  36. Luo G, Ducy P, McKee MD, Pinero GJ, Loyer E, Behringer RR, Karsenty G. Spontaneous calcification of arteries and cartilage in mice lacking matrix GLA protein. Nature. 1997;385:78–81.[Medline] [Order article via Infotrieve]
  37. Bucay N, Sarosi I, Dunstan CR, Morony S, Tarpley J, Capparelli C, Scully S, Tan HL, Xu W, Lacey DL, Boyle WJ, Simonet WS. Osteoprotegerin-deficient mice develop early onset osteoporosis and arterial calcification. Genes Dev. 1998;12:1260–1268.[Abstract/Free Full Text]
  38. NIH Working Group. "New Evidence Connecting Cardiovascular Disease and Osteoporosis" September 14–15, 1999, Bethesda, Maryland; sponsored by Drs Claude Lenfant, Director of the National Heart Lung and Blood Institute, and Stephen I. Katz, Director of the National Institute of Arthritis and Musculoskeletal Disease. A summary of this meeting is available at www.nhlbi.nih.gov/meetings/workshops/bnhrtsm.htm.



This article has been cited by other articles:


Home page
J. Gerontol. A Biol. Sci. Med. Sci.Home page
M. M. Pinheiro, C. M. Castro, and V. L. Szejnfeld
Low femoral bone mineral density and quantitative ultrasound are risk factors for new osteoporotic fracture and total and cardiovascular mortality: a 5-year population-based study of brazilian elderly women.
J. Gerontol. A Biol. Sci. Med. Sci., February 1, 2006; 61(2): 196 - 203.
[Abstract] [Full Text] [PDF]


Home page
CirculationHome page
C. Farrington-Rock, N.J. Crofts, M.J. Doherty, B.A. Ashton, C. Griffin-Jones, and A.E. Canfield
Chondrogenic and Adipogenic Potential of Microvascular Pericytes
Circulation, October 12, 2004; 110(15): 2226 - 2232.
[Abstract] [Full Text] [PDF]


Home page
Am J EpidemiolHome page
L. Jorgensen, O. Joakimsen, G. K. Rosvold Berntsen, I. Heuch, and B. K. Jacobsen
Low Bone Mineral Density Is Related to Echogenic Carotid Artery Plaques: A Population-based Study
Am. J. Epidemiol., September 15, 2004; 160(6): 549 - 556.
[Abstract] [Full Text] [PDF]


Home page
Obstet GynecolHome page
A. Poli, F. Bruschi, B. Cesana, M. Rossi, R. Paoletti, and P. G. Crosignani
Plasma Low-Density Lipoprotein Cholesterol and Bone Mass Densitometry in Postmenopausal Women
Obstet. Gynecol., November 1, 2003; 102(5): 922 - 926.
[Abstract] [Full Text] [PDF]


Home page
J. Dent. Res.Home page
A. Taguchi, Y. Suei, M. Sanada, Y. Higashi, M. Ohtsuka, T. Nakamoto, M. Tsuda, K. Ohama, and K. Tanimoto
Detection of Vascular Disease Risk in Women by Panoramic Radiography
J. Dent. Res., October 1, 2003; 82(10): 838 - 843.
[Abstract] [Full Text] [PDF]


Home page
J. Biol. Chem.Home page
Y. Tintut, F. Parhami, A. Tsingotjidou, S. Tetradis, M. Territo, and L. L. Demer
8-Isoprostaglandin E2 Enhances Receptor-activated NFkappa B Ligand (RANKL)-dependent Osteoclastic Potential of Marrow Hematopoietic Precursors via the cAMP Pathway
J. Biol. Chem., April 12, 2002; 277(16): 14221 - 14226.
[Abstract] [Full Text] [PDF]


Home page
Arterioscler. Thromb. Vasc. Bio.Home page
L. L. Demer
Boning Up (or Down) on Statins
Arterioscler. Thromb. Vasc. Biol., October 1, 2001; 21(10): 1565 - 1566.
[Full Text] [PDF]


This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Parhami, F.
Right arrow Articles by Demer, L. L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Parhami, F.
Right arrow Articles by Demer, L. L.
Right arrowPubmed/NCBI databases
*Substance via MeSH
Medline Plus Health Information
*Osteoporosis