osteoprotegerin and Hypercalciuria

A limited number of studies have evaluated biochemical bone metabolism markers in children with idiopathic hypercalciuria, which in adults has been linked with osteopenia. Our aim was to investigate in children with idiopathic hypercalciuria biochemical markers of bone formation and resorption and the osteoprotegerin (OPG) and soluble receptor activator of nuclear factor kB ligand (sRANKL) system which is involved in the osteoclastogenesis process.. A prospective study was conducted on 50 children with idiopathic hypercalciuria and 50 healthy age-, sex-, and Tanner stage-matched control subjects. Following the diagnosis, patients were requested to follow a 3-month dietary recommendation for idiopathic hypercalciuria. In patients, at diagnosis and at 3 months of follow-up, and in controls, bone-related hormones and serum/urine biochemical parameters were studied. The bone formation markers (total ALP and osteocalcin) and the bone resorption markers (β-Crosslaps) and the OPG and sRANKL levels were determined.. No differences were found in the bone formation markers or OPG and sRANKL between the children with idiopathic hypercalciuria and controls. The β-Crosslaps and the β-Crosslaps/osteocalcin ratio were higher in the patients at diagnosis than in controls (p = 0.019 and p = 0.029, respectively), with a trend to decrease after the 3-month dietary intervention. The initially increased 24-h urinary Ca in the patients decreased after the 3-month dietary intervention (p = 0.002).. Children with idiopathic hypercalciuria had biochemical markers compatible with normal bone formation but increased bone resorption. After a 3-month dietary intervention, the trend observed towards decrease in the serum β-Crosslaps may reflect a beneficial response.

Topics: Biomarkers; Bone and Bones; Bone Diseases, Metabolic; Bone Resorption; Case-Control Studies; Child; Child, Preschool; Female; Humans; Hypercalciuria; Longitudinal Studies; Male; Osteocalcin; Osteogenesis; Osteoprotegerin; Prospective Studies; RANK Ligand; Treatment Outcome

The present study was performed in order to examine bone loss and calcium homeostasis in mice with glucocorticoid (GC)-induced osteoporosis (GIOP) following treatment with the aqueous extract of pomegranate seed (AE-PS). In addition, a comparative study with alendronate was performed. Biomarkers in the serum and the urine were measured. The tibias, kidney and duodenum were removed in order to measure the levels of bone calcium, protein expression as well as to perform histomorphological analysis of the bone. GC treatment facilitated the induction of hypercalciuria in the mice, and the AE-PS‑treated mice exhibited a greater increase in serum calcium and a decrease in urine calcium. The AE-PS reversed the deleterious effects on the trabecular bone induced by DXM and stimulated bone remodeling, including an increase in bone calcium and alkaline phosphatase‑b (ALP-b) and a decrease in a the critical bone resorption markers C-terminal telopeptide of type I collagen (CTX) and tartrate‑resistant acid phosphatase-5b (TRAP-5b). Hematoxylin and eosin (H&E) staining revealed the increased disconnections and separation between the growth plate and the trabecular bone network as well as the reduction in the trabecular bone mass of the primary and secondary spongiosa throughout the proximal metaphysis of the tibia in the DXM group. Moreover, the decreased protein expression of transient receptor potential vanilloid (TRPV)5, TRPV6 and calbindin‑D9k (CaBP‑9k) was reversed by the AE-PS or alendronate supplementation in the kidneys and the duodenum as well as plasma membrane Ca2+‑ATPase1 (PMCA1) expression in the kidneys of mice with GIOP. There was no marked difference in pharmacological effectiveness between alendronate and the AE-PS. Taken together, these findings suggest that the AE-PS may be an alternative therapy suitable for use in the management of secondary osteoporosis.

Topics: Alendronate; Animals; Bone Resorption; Calcium; Duodenum; Glucocorticoids; Hypercalciuria; Kidney; Lythraceae; Male; Membrane Transport Proteins; Mice, Inbred C57BL; Osteoprotegerin; Phytotherapy; Plant Extracts; RANK Ligand; Receptors, Calcium-Sensing; Seeds; Tartrate-Resistant Acid Phosphatase; Testosterone; Tibia; Water

This study aimed to determine the expression of osteoprotegerin, receptor activator of nuclear factor kappaB ligand, interleukin-1alpha, transforming growth factor-beta, and basic fibroblast growth factor in stone-forming patients with idiopathic hypercalciuria.. Immunohistochemical analysis was performed in undecalcified bone samples previously obtained from 36 transiliac bone biopsies of patients who had idiopathic hypercalciuria and whose histomorphometry had shown lower bone volume, increased bone resorption, and prolonged mineralization lag time.. Bone expression of receptor activator of nuclear factor kappaB ligand and osteoprotegerin was significantly higher in patients with idiopathic hypercalciuria versus control subjects. Transforming growth factor-beta immunostaining was lower in patients with idiopathic hypercalciuria than in control subjects and correlated directly with mineralization surface. Interleukin-1alpha and basic fibroblast growth factor staining did not differ between groups. Receptor activator of nuclear factor kappaB ligand bone expression was significantly higher in patients who had idiopathic hypercalciuria and exhibited higher versus normal bone resorption.. A higher expression of receptor activator of nuclear factor kappaB ligand in bone tissue suggests that increased bone resorption in patients with idiopathic hypercalciuria is mediated by receptor activator of nuclear factor kappaB ligand. Osteoprotegerin bone expression might have been secondarily increased in an attempt to counteract the actions of receptor activator of nuclear factor kappaB ligand. The low bone expression of transforming growth factor-beta could contribute to the delayed mineralization found in such patients.

Topics: Adult; Bone Density; Bone Resorption; Case-Control Studies; Female; Fibroblast Growth Factor 2; Humans; Hypercalciuria; Ilium; Immunohistochemistry; Interleukin-1alpha; Male; Middle Aged; Osteoprotegerin; RANK Ligand; Transforming Growth Factor beta; Up-Regulation