Understanding the Cellular and Molecular Mechanisms of Physical Activity-Induced Health Benefits.

The beneficial effects of physical activity (PA) are well documented, yet the mechanisms by which PA prevents disease and improves health outcomes are poorly understood. To identify major gaps in knowledge and potential strategies for catalyzing progress in the field, the NIH convened a workshop in late October 2014 entitled "Understanding the Cellular and Molecular Mechanisms of Physical Activity-Induced Health Benefits." Presentations and discussions emphasized the challenges imposed by the integrative and intermittent nature of PA, the tremendous discovery potential of applying "-omics" technologies to understand interorgan crosstalk and biological networking systems during PA, and the need to establish an infrastructure of clinical trial sites with sufficient expertise to incorporate mechanistic outcome measures into adequately sized human PA trials.

Randomized trial of once-weekly parathyroid hormone (1-84) on bone mineral density and remodeling.

Context: Daily PTH administration increases bone mineral density (BMD) and reduces fracture risk. However, cost and compliance significantly limit clinical use.

Objective: Our objective was to determine whether less frequent PTH administration increases lumbar spine BMD.

One year of alendronate after one year of parathyroid hormone (1-84) for osteoporosis.

Background: Since the use of parathyroid hormone as a treatment for osteoporosis is limited to two years or less, the question of whether antiresorptive therapy should follow parathyroid hormone therapy is important. We previously reported results after the first year of this randomized trial comparing the use of full-length parathyroid hormone (1-84) alone, alendronate alone, or both combined. In the continuation of this trial, we asked whether antiresorptive therapy is required to maintain gains in bone mineral density after one year of therapy with parathyroid hormone (1-84).

The effects of parathyroid hormone and alendronate alone or in combination in postmenopausal osteoporosis.

Background: Parathyroid hormone increases bone strength primarily by stimulating bone formation, whereas antiresorptive drugs reduce bone resorption. We conducted a randomized, double-blind clinical study of parathyroid hormone and alendronate to test the hypothesis that the concurrent administration of the two agents would increase bone density more than the use of either one alone.

Methods: A total of 238 postmenopausal women (who were not using bisphosphonates) with low bone mineral density at the hip or spine (a T score of less than -2.

Perspectives on the future of bone and joint diseases.

The diseases of bones, joints, and muscles are common, chronic, and very costly to society. While the impact of these diseases falls across the age spectrum, the worldwide growth in the percentage of elderly in the population makes attention to musculoskeletal disorders and conditions particularly critical. An effective prevention strategy, driven by an understanding of the fundamental biology of bone and connective tissue, can only result from an upshift in the efforts of many sectors--public and private, academic, scientific, and patient-based--with new opportunities for partnerships and collaborative efforts flourishing.