Mechanisms of Ageing and Development 102 (1998) 293–298 Serum -2 microglobulin is a marker of high bone remodelling in elderly women Jose ´ Manuel Quesada a, *, Jesus Alonso a , Jose Gonzalez a , Rafael Mun ˜oz a , Ivo Jans b , Antonio Martiu a , Roger Bouillon b a Unidad de Metabolismo Mineral, Hospital Uniersitario Reina Sofı ´a, Facultad de Medicina y Departamento de Biologı ´a Celular, Uniersidad de Co ´rdoba, 14004 Co ´rdoba, Spain b Laboratorium oor Experimentele Geneeskunde en Endocrinologie, Katholieke Uniersiteit Leuen, B-3000 Leuen, Belgium Received 27 August 1997; received in revised form 20 November 1997; accepted 4 January 1998 Abstract -2 microglobulin (2m), the water soluble extrinsic light chain of class I MHC, has been recently isolated from the adult bone culture medium. Serum 2m plays a role as a bone-derived growth factor regulating both osteoblast and osteoclast cell activity. Serum 2m has been proposed as a bone remodeling biological marker in high bone turnover conditions. The purpose of our study was to determine the relationship between 2m and vitamin D status in post-menopausal women. We have studied 44 healthy women from 20 to 80 years with normal hepatic and renal function, without diabetes mellitus and/or inflamma- tory, tumoral or infectious diseases. We measured the serum levels of calcium, phosphorus, parathyroid hormone (PTH), vitamin D binding protein (DBP), 25-OHD 3 (calcidiol), 1,25(OH) 2 D 3 (calcitriol) and 2m. Serum 2m levels increased with age (r =0.54, P 0.001). Post-menopausal women had higher serum levels than pre-menopausal women of 2m (1.76 0.22 mg/l vs. 1.35 0.2 mg/l, P 0.01); PTH (61.5 7.5 ng/ml vs. 39 6 ng/ml, P 0.001) and lower serum levels of 25-OHD 3 (7.5 2.3 ng/ml vs. 18.2 2.5 ng/ml, P 0.001). Moreover, serum levels of 2m were negatively correlated with 25-OHD 3 (r =-0.34, P 0.05) and with ionized calcium (r =-0.45, P 0.01) and positively with * Corresponding author, Unidad de Metabolismo Mineral, Hospital Provincial, Hospital Universi- tario ‘Reina Sofı ´a’, Avda. Mene ´ndez Pidal s/n, 14004 Co ´ rdoba, Spain. 0047-6374/98/$19.00 © 1998 Elsevier Science Ireland Ltd. All rights reserved. PII S0047-6374(98)00019-0