Planta Med 2009; 75(5): 459-465
DOI: 10.1055/s-0029-1185380
Rapid Communication
Original Paper
© Georg Thieme Verlag KG Stuttgart · New York

Equol but not Genistein Improves Early Metaphyseal Fracture Healing in Osteoporotic Rats

Leila Kolios1 , Stephan Sehmisch1 , Florian Daub1 , Thomas Rack1 , Mohammed Tezval1 , Klaus Michael Stuermer1 , Ewa Klara Stuermer1
  • 1Department of Trauma and Reconstructive Surgery, Georg-August-University of Goettingen, Goettingen, Germany
Further Information

Publication History

received July 29, 2008 revised January 8, 2009

accepted January 13, 2009

Publication Date:
24 February 2009 (online)

Abstract

Healing of predominantly metaphyseal fractures in postmenopausal osteoporosis is delayed and comparatively poor. Hormone replacement therapy could improve fracture healing, but, because of its potential side effects, natural alternatives are more appealing. The aim of this study was to determine if the soy metabolite equol and the native isoflavone genistein, in comparison to 17β-estradiol, improve metaphyseal fracture healing in ovariectomy-induced osteoporotic bone of the rat. Forty-eight 12-week-old female rats developed severe osteoporosis ten weeks after ovariectomy. After metaphyseal tibial osteotomy and standardized stable internal fixation, changes in callus morphology were evaluated biomechanically, qualitatively and quantitatively in fluorochrome-labeled histological sections and microradiographs in ovariectomized rats (C) and under standardized 17β-estradiol (E), equol (EQ) and genistein (G) supplemented rats over a period of five weeks. Estrogen and equol were able to improve the elasticity of callus formation significantly in postmenopausal osteoporotic bone (stiffness of C: 121.40 ± 47.08 N/mm, E: 147.90 ± 39.38 N/mm, EQ: 167.8 ± 59.90 N/mm). The effects of estrogen were more anabolic than those of equol and were visible in changes to the trabecular bone (N.Nd of E: 6.47 ± 7.68, EQ: 4.25 ± 3.96). However, in terms of the whole body, equol seemed to induce less of an adverse reaction than estrogen (body weight of C: 342.20 ± 19.91 g, E: 280.25 ± 12.05 g, EQ: 308.75 ± 24.28 g). Genistein as an osteoclast inhibitor influenced callus stiffness (G: 144.50 ± 61.52 N/mm) and negatively impacted trabecular structure (N.Nd of G: 0.59 ± 1.01) in severely osteoporotic bones. Estrogen and equol were able to improve fracture healing in ovariectomy-induced osteoporotic bones, and the extent of callus formation played only a minor role. Genistein rather negatively influenced fracture healing. The metaphyseal osteotomy model in ovariectomized rats allows an accurate study of the therapeutic effects of antiosteoporotic substances on the fracture healing process.

References

  • 1 Savoca S, D'Agosta S, Lombardo G. Evaluation of the hematochemical parameters and bone mineral density of women in physiological menopause treated with hormone replacement therapy with nomegestrol acetate and surgical menopause treated with estrogen replacement. Part II.  Minerva Ginecol. 2007;  59 215-222
  • 2 Boonen S, Marin F, Obermayer-Pietsch B, Simoes M E, Barker C, Glass E V, Hadji P, Lyritis G, Oertel H, Nickelsen T, McCloskey E V. EUROFORS Investigators . Effects of previous antiresorptive therapy on the bone mineral density response to two years of teriparatide treatment in postmenopausal women with osteoporosis.  J Clin Endocrinol Metab. 2008;  93 852-860
  • 3 Lill C A, Gerlach U V, Eckhardt C, Goldhahn J, Schneider E. Bone changes due to glucocorticoid application in an ovariectomized animal model for fracture treatment in osteoporosis.  Osteoporos Int. 2002;  13 407-414
  • 4 McCann R M, Colleary G, Geddis C, Clarke S A, Jordan G R, Dickson G R, Marsh D. Effect of osteoporosis on bone mineral density and fracture repair in a rat femoral fracture model.  J Orthop Res. 2008;  26 384-393
  • 5 Tarakida A, Higuchi T, Mizunuma H. Evidence of hormone replacement therapy for osteoporosis.  Maturitas. 2007;  PMID 18830040
  • 6 Horwitz K B. The year in basic science: update of estrogen plus progestin therapy for menopausal hormone replacement implicating stem cells in the increased breast cancer risk.  Mol Endocrinol. 2008;  PMID 18845670
  • 7 Beral V. Breast cancer and hormone-replacement therapy in the Million Women Study.  Lancet. 2003;  362 419-427
  • 8 Rossouw J E, Anderson G L, Prentice R L. Risks and benefits of estrogen plus progestin in healthy postmenopausal women: principal results from the Women's Health Initiative randomized controlled trial.  JAMA. 2002;  288 321-333
  • 9 Gustafsson J-A. Estrogen receptor β – a new dimension in estrogen mechanism of action.  J Endocrinol. 1999;  163 379-383
  • 10 Mathey J, Mardon J, Fokialakis N, Puel C, Kati-Coulibali S, Mitakou S, Bennetau-Pelissero C, Lamothe V, Davicco M J, Lebecque P, Horcajada M N, Coxam V. Modulation of soy isoflavones bioavailability and subsequent effects on bone health in ovariectomized rats: the case for equol.  Osteoporos Int. 2007;  18 671-679
  • 11 Picherit C, Coxam V, Benneteau-Pelissero C, Kati-Coulibali S, Davicco Lebecque M JE, Barlet J P. Daidzein is more efficient than genistein in preventing ovariectomy-induced bone loss in rats.  J Nutr. 2000;  130 1675-1681
  • 12 Sehmisch S, Hammer F, Christoffel J, Seidlova-Wuttke D, Tezval M, Wuttke W, Stuermer K M, Stuermer E K. Using the biomechanical properties of bone to compare genistein, resveratrol and 8-prenylaringenin as agent for preventing osteoporosis.  Planta Med. 2008;  74 794-801
  • 13 Gao Y H, Yamagushi M. Suppressive effect of genistein on rat bone osteoclasts: involvement of protein kinase inhibition and protein tyrosine phosphatase activation.  Int J Mol Med. 2000;  5 261-267
  • 14 Yokohama S, Suzuki T. Isolation and characterization of a novel equol-producing bacterium from human feces.  Biosci Biotechnol Biochem. 2008;  72 2660-2666
  • 15 Setchell K D, Clerici C, Lephart E D. S-equol. A potent ligand for estrogen receptor beta, is the exclusive enantiomeric form of the soy isoflavone metabolite produced by human intestinal bacterial flora.  Am J Clin Nutr. 2005;  81 1072-1079
  • 16 Atkinson C, Frankenfeld C L, Lampe J W. Gut bacterial metabolism of the soy isoflavone daidzein: exploring the relevance to human health.  Exp Biol Med (Maywood). 2005;  230 155-170
  • 17 Stuermer E K, Sehmisch S, Rack T, Seidlova-Wuttke D, Tezval M, Wuttke W, Frosch K H, Stuermer K M. Estrogen and raloxifene improve metaphyseal fracture healing in the early phase of osteoporosis. A new fracture-healing model at the tibia in rat.  Lang Arch Surg. 2008;  PMID 19048282
  • 18 Seidlova-Wuttke D, Hesse O, Jarry H, Christoffel V, Spengler B, Becker T, Wuttke W. Evidence for selective estrogen receptor modulator activity in a black cohosh (Cimifuga racemosa) extract: comparison with estradiol-17β.  Eur J Endocrinol. 2003;  149 336-351
  • 19 Stürmer E K, Seidlova-Wuttke D, Sehmisch S, Rack T, Wille J, Frosch K H, Wuttke W, Stürmer K M. Standardized bending and breaking test for the normal and osteoporotic metaphyseal tibias of the rat: effect of estradiol, testosterone, and raloxifene.  J Bone Miner Res. 2006;  21 89-96
  • 20 Schenk R K. The histological preparation of undecalcified bone.  Acta Anat. 1965;  60 3-19
  • 21 Parfitt A M, Drezner M K, Glorieux F H, Kanis J A, Malluche H, Meunier P J, Ott S M, Recker R R. Bone histomorphometry: standardization of nomenclature, symbols, and units. Report of the ASBMR Histomorphometry Nomenclature Committee.  J Bone Miner Res. 1987;  2 595-610
  • 22 Cao Y, Mori S, Mashiba T, Westmoore M S, Ma L, Sato M, Akiyama T, Shi L, Komatsubara S, Miyamoto K, Norimatsu H. Raloxifene, estrogen and alendronate affect the processes of fracture repair differently in ovariectomized rats.  J Bone Miner Res. 2002;  17 2237-2246
  • 23 Schmidmaier G, Wildemann B, Bail H, Lucke M, Fuchs T, Stemberger A, Flyvberg A, Haas N P, Raschke M. Local application of growth factors (insulin-like growth factor-1 and transforming growth factor-β) from a biodegradable poly (D,L-lactide) coating of osteosynthetic implants accelerated fracture healing in rats.  Bone. 2001;  28 341-350
  • 24 Wronski T J, Yen C F. The ovariectomized rat as an animal model for postmenopausal bone loss.  Cells Mater Suppl . 1991;  1 69-74
  • 25 Setchell K D, Cole S J. Method of defining equol-producer status and its frequency among vegetarians.  J Nutr. 2006;  136 2188-2193
  • 26 Yamagishi T, Otsuka E, Hagiwara H. Reciprocal control of expression of mRNAs for osteoclast differentiation factor and OPG in osteogenic stromal cells by genistein: evidence for the involvement of topoisomerase II in osteoclastogenesis.  Endocrinology. 2001;  142 3632-3637
  • 27 Rachon D, Seidlova-Wuttke D, Vortherms T, Wuttke W. Effects of dietary equol on body weight gain, intra-abdominal fat accumulation, plasma lipids, and glucose tolerance in ovariectomized Sprague-Dawley rats.  Menopause. 2007;  14 925-932
  • 28 Rachon D, Vortherms T, Seidlova-Wuttke D, Wuttke W. Effects of dietary equol administration on ovariectomy induced bone loss in Sprague-Dawley rats.  Clin Calcium. 2008;  18 1434-1441

Dr. Leila Kolios

Department of Trauma and Reconstructive Surgery
Georg-August-University of Goettingen

Robert-Koch-Straße 40

37075 Goettingen

Germany

Email: leilakolios@med.uni-goettingen.de

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