Effect of Bisphosphonate In Insufficiency State Of Vitamin D. Preliminary Experimental Study

S. ZENI; S. MASTAGLIA; P MANDALUNIS; M C DEGRANDI; M.B. OLIVERI,; J SOMOZA

Seatle

Congreso; 26th Anual Meeting ASBMR; 2004

ASBMR

S. N. Zeni1, S. R. Mastaglia*1, P. Mandalunis*2, M. C. Degrandi*1, M. B. Oliveri1, J. Somoza*1. 1SecciónOsteopatías Médicas, Hospital de Clínicas, University of Buenos Aires, Buenos Aires, Argentina,2Catedra de Fisiología, School of Dentistry, University of Buenos Aires, Buenos Aires, Argentina.Presentation Number: M412It is known that vitamin D insufficiency or deficiency has negative effects on skeletal metabolism.Experimental bone loss is achieved by ovariectomy (OVX) in rats by incresing bone turnover.Bisphosphonates (BPs) are useful antiresortive agents to inhibit resorption in several bone diseases.Hypothetically vitamin D insufficiency could affect bisphosphonate therapy. The aim of the presentpreliminary study was to investigate whether bone mass recovery due to olpadronate (OPD) treatment isaffected by Vitamin D status- i.e. normal or insufficiency, using OVX rats with established osteopenia. Atotal of 16 female Wistar rats (280-300 g) were OVX: 8 rats were fed a synthetic diet that covered alladequate requirements (+VitD); 8 rats were housed under red light and fed the same synthetic diet lackingof Vitamin D (-VitD). During 60 days rats lost approximately 15% of bone mass, after that (To) 8 rats of+VitD group and all rats of -VitD group received during a 45-day period (Tf) 16ug OPD/100g rat weekly.Simultaneously, 8 OVX and 8 SHAM rats were fed the synthetic diet throughout the study and onlyreceived placebo treatment. Bone mineral density (BMD) (mg/cm2), 25OHvitamin D (ng/ml), bonealkaline phosphate (mUI/ml) and serum CTX (ng/ml) were assessed at To and Tf and tibiahistomorphometry was made at Tf. (Table).Different letters indicated a p<0.05. Bone recovery by OPDtreatment was greater in +VitD than in -Vit D. At Tf sCTX was lower and 25OHVitD was higher than in-VitD group. The +VitD group presented greater bone volume and lower erosive surface than -VitDgroup. Conclusion: These results suggest that OPD effects may be less beneficial in vitamin D deficientstate.