TY - JOUR
A2 - Husain, Kazim
AU - Pacheco-Costa, Rafael
AU - Campos, Jenifer Freitas
AU - Katchburian, Eduardo
AU - de Medeiros, ValquÃria Pereira
AU - Nader, Helena Bonciani
AU - Nonaka, Keico Okino
AU - Plotkin, Lilian Irene
AU - Reginato, Rejane Daniele
PY - 2015
DA - 2015/01/28
TI - Modifications in Bone Matrix of Estrogen-Deficient Rats Treated with Intermittent PTH
SP - 454162
VL - 2015
AB - Bone matrix dictates strength, elasticity, and stiffness to the bone. Intermittent parathyroid hormone (iPTH), a bone-forming treatment, is widely used as a therapy for osteoporosis. We investigate whether low doses of intermittent PTH (1-34) change the profile of organic components in the bone matrix after 30 days of treatment. Forty 6-month-old female Wistar rats underwent ovariectomy and after 3 months received low doses of iPTH administered for 30 days: daily at 0.3 µg/kg/day (PTH03) or 5 µg/kg/day (PTH5); or 3 times per week at 0.25 µg/kg/day (PTH025). After euthanasia, distal femora were processed for bone histomorphometry, histochemistry for collagen and glycosaminoglycans, biochemical quantification of sulfated glycosaminoglycans, and hyaluronan by ELISA and TUNEL staining. Whole tibiae were used to estimate the bone mineral density (BMD). Histomorphometric analysis showed that PTH5 increased cancellous bone volume by 6% over vehicle-treated rats. In addition, PTH5 and PTH03 increased cortical thickness by 21% and 20%, respectively. Tibial BMD increased in PTH5-treated rats and this group exhibited lower levels of chondroitin sulfate; on the other hand, hyaluronan expression was increased. Hormonal administration in the PTH5 group led to decreased collagen maturity. Further, TUNEL-positive osteocytes were decreased in the cortical compartment of PTH5 whereas administration of PTH025 increased the osteocyte death. Our findings suggest that daily injections of PTH at low doses alter the pattern of organic components from the bone matrix, favoring the increase of bone mass.
SN - 2314-6133
UR - https://doi.org/10.1155/2015/454162
DO - 10.1155/2015/454162
JF - BioMed Research International
PB - Hindawi Publishing Corporation
KW -
ER -