Endocrine Abstracts

Background: Excess glucocorticoids are well recognised as a cause of osteoporosis; they inhibit osteoblast function and increase osteoblast and osteocyte apoptosis resulting in thinning of the trabeculae. The circadian rhythm of bone turnover, which is linked to cortisol rhythm, is abnormal in osteoporosis. Furthermore, some studies show abnormal cortisol metabolism in osteoporosis. The aim of our study was to evaluate the day–night rhythm of cortisol and to relate cortis...

Bone turnover markers reflect the work of the osteoblast and the osteoclast. They can be measured in blood or urine and allow for an inexpensive and non-invasive way to study bone metabolism. They have been evaluated for their use in predicting risk of fracture, accelerated bone loss or the presence of secondary osteoporosis, but for all these uses they are not yet established. They are useful in monitoring the response to treatment of osteoporosis, especially with drugs such ...

The fractures that result from postmenopausal osteoporosis have a major public health impact. We have a number of drugs we can use to reduce the risk of these fractures. Most of these drugs are anti-resorptive, such as the bisphosphonates (alendronate, ibandronate, risedronate and zoledronate), raloxifene, oestrogen, and denosumab. Until recently the only anabolic agent available was teriparatide. However, in the last couple of years two new agents have been approved in some c...

I received a clinical fellowship from the Medical Research Council to study osteoporosis at the University of Edinburgh in 1978. I furthered my clinical research training by working at the Mayo Clinic under the supervision of Dr B L Riggs where I worked for five years. I developed a number of new approaches for studying osteoporosis while at the Mayo Clinic including the use of stable (non-radioactive) isotopes to measure the absorption of calcium from food, the use of an infu...

Osteoporosis is a silent disorder characterized by reduced bone strength predisposing to increased fracture risk. Although osteoporosis affects women more often than men, ~20% of the 44 million Americans who have osteoporosis or low BMD are men. Between 30 and 40% of fractures due to osteoporosis occur in men; the lifetime risk of fracture for men aged 50 or older is between 13 and 30%. Osteoporosis in men causes significant morbidity and mortality. The major mechanism underly...

The explosion in our understanding of bone biology has resulted in a number of key targets in bone that should allow the development of new treatments. There are other important regulators of bone resorption that are being targeted and these include src kinase and the chloride channel on osteoclasts. The key enzyme in bone resorption is cathepsin K and small molecule inhibitors have been developed and these are currently in phase II and III clinical trials. These are an intere...

A number of new treatments are being developed for the treatment of bone diseases, particularly osteoporosis. We need tools to help identify how these drugs work and which bone compartment they affect. Bone turnover markers are very useful in identifying response to treatment in these allow identification of an early change and information about mechanism. New biochemical tests have become available that allow study of the key regulatory pathways in bone – these include o...

High-resolution peripheral computed tomography (HR-pQCT) (XtremeCT, Scanco) obtains three-dimensional images of the distal radius with a resolution of 82 microns, which enables detailed study of the microarchitecture of cortical and trabecular bone. Better description of the microarchitectural changes in bone with ageing will improve understanding of which preventative and therapeutic interventions are most likely to be effective.The aim of this study wa...

The injectable contraceptive depot medroxyprogesterone acetate (DMPA, Depo-Provera®) is used by over nine million women worldwide. It induces amenorrhoea, raising concern about effects on bone density. This study aims to ascertain if the skeletal effects of DMPA are age-specific and to identity the mechanisms through which DMPA acts on the skeleton. The study was approved by the local Ethics Committee. We recruited 100 pairs of women ages 18–25 and 35&#150...

Introduction: Avascular necrosis of the femoral head (AVN) is most commonly a consequence of glucocorticoid excess and is believed to be due to osteocyte apoptosis. It can also be due to vascular occlusion or trauma. We describe a patient with congenital adrenal hyperplasia secondary to 17-hydroxylase deficiency who presented with osteoporotic vertebral fractures and atraumatic avascular necrosis of the femoral head. She was also found to have mild cardiomyopathy.<p class=...