Learn More
Postmenopausal osteoporosis, a global public health problem, has for decades been attributed solely to declining estrogen levels. Although FSH levels rise sharply in parallel, a direct effect of FSH on the skeleton has never been explored. We show that FSH is required for hypogonadal bone loss. Neither FSHbeta nor FSH receptor (FSHR) null mice have bone(More)
CD38 is an ectocyclase that converts NAD+ to the Ca2+-releasing second messenger cyclic ADP-ribose (cADPr). Here we report that in addition to CD38 ecto-catalysis, intracellularly expressed CD38 may catalyze NAD+-->cADPr conversion to cause cytosolic Ca2+ release. High levels of CD38 were found in the plasma membranes, endoplasmic reticulum, and nuclear(More)
We have evaluated the role of the ADP-ribosyl cyclase, CD38, in bone remodeling, a process by which the skeleton is being renewed constantly through the coordinated activity of osteoclasts and osteoblasts. CD38 catalyzes the cyclization of its substrate, NAD+, to the Ca2+-releasing second messenger, cyclic ADP-ribose (cADPr). We have shown previously that(More)
We predict that the type 2 ryanodine receptor isoform (RyR-2) located in the osteoclastic membrane functions as a Ca(2+) influx channel and as a divalent cation (Ca(2+)) sensor. Cytosolic Ca(2+) measurements revealed Ca(2+) influx in osteoclasts at depolarized membrane potentials. The cytosolic Ca(2+) change was, as expected, not seen in Ca(2+)-free medium(More)
The causes for the propensity of metastasized prostate cancer cells to grow in bone and to induce osteoblastic lesions remain unresolved. Co-culture of human prostate cancer cell lines with bone slices was determined to increase the level of endothelin-1 (ET-1) mRNA and its production. ET-1 is an ejaculate protein that also stimulates osteoblasts.(More)
We describe a physiologically significant mechanism through which interleukin-6 (IL-6) and a rising ambient Ca2+ interact to regulate osteoclastic bone resorption. VOXEL-based confocal microscopy of nonpermeabilized osteoclasts incubated with anti- IL-6 receptor antibodies revealed intense, strictly peripheral plasma membrane fluorescence. IL-6 receptor(More)
The multifunctional ADP-ribosyl cyclase, CD38, catalyzes the cyclization of NAD ϩ to cyclic ADP-ribose (cADPr). The latter gates Ca 2 ϩ release through microsomal membrane-resident ryanodine receptors (RyRs). We first cloned and sequenced full-length CD38 cDNA from a rabbit osteoclast cDNA library. The predicted amino acid sequence displayed 59, 59, and 50%(More)
Here, we demonstrate that the Ca(2+)/calmodulin-sensitive phosphatase calcineurin is a necessary downstream mediator for osteoclast differentiation. Using quantitative PCR, we detected the calcineurin isoforms Aalpha, Abeta, Agamma (catalytic), and B1 (regulatory) in osteoclast precursor RAW-C3 cells. We found that, although the expression of these isoforms(More)
  • 1