Osteoporosis Home > Osteoporosis Research
In the past decade, there has been an explosion of basic and clinical research in osteoporosis. However, many fundamental advances in molecular and cellular biology, immunology, genetics, and bioengineering have not yet been applied to skeletal biology. In addition, research on SERMs holds promise for reducing bone loss in postmenopausal women without adverse effects on other organs. Vast opportunities exist to expand the current knowledge base, continuing in a diverse approach to osteoporosis prevention and treatment. Initiatives that may serve as springboards for further research include:
- Multicenter clinical intervention studies on combination therapies for osteoporosis. Because pharmaceutical companies tend to focus resources on bringing individual drugs to market, federal support is needed to test combinations of drugs, as well as possible exercise and nutritional modifications to various drug combinations. Lower doses and combinations of effective agents may reduce the side effects and risks associated with current individual drug treatments, and may improve overall responsiveness. These studies will also generate information on osteoporosis in men, children, adolescents, and those who have diseases and conditions that put them at high risk for osteoporosis, moving beyond postmenopausal women, the group on whom most private-sector research has been concentrated.
- The bone density, biomarkers, and physical activity component of the National Health and Nutrition Examination Survey (NHANES) IV. National Health and Nutrition Examination Surveys have been conducted periodically since the 1960s through household interviews and physical examinations provided in specially designed mobile examination centers, and with data collection periods ranging from 3 to 6 years. NHANES IV is planned as a continuous survey, and new data collection began in 1999. NIAMS is specifically interested in information from three tests to be included in the exam: dual energy x-ray absorptiometry (DEXA), measurements of markers of bone resorption in urine and blood samples, and assessment of musculoskeletal strength in participants age 50 and over.
- Understanding the effects of therapeutic agents. While estrogen continues to be an important hormone for the treatment of osteoporosis, particularly in postmenopausal women, new treatment drugs that may prove helpful to a broader population have recently been introduced into the marketplace. These include alendronate (a bisphosphonate) and raloxifene (a selective estrogen receptor modulator). Recent knowledge about the link between bone and the cardiovascular system suggests that drugs commonly used to reduce cholesterol may also have beneficial effects on the skeleton. NIAMS is supporting research that examines the molecular and cellular mechanisms by which currently used agents work in the hope of advancing knowledge about their application to bone.
- Animal models to study the bone matrix. There is growing evidence suggesting that the bone matrix is a source of important biochemical signals that influence the activity of bone cells, telling them where to break down or form new bone. The identification of matrix components that influence cell function could lead to new drugs that mimic these signals. NIAMS supports research that uses new, genetically modified mice as a model to examine the interaction between bone cells and the bone matrix.
- Control of osteoblast differentiation. Osteoblasts (bone-forming cells) arise from precursor cells that separate to form different tissues. Some osteoblasts differentiate further to become osteocytes, the cells that are thought to be important for the response of bone to mechanical loading. The complex balance between the generation of precursor cells, their differentiation into osteoblasts and osteocytes, and ultimately their death, determines the rate of new bone formation. NIAMS is encouraging research that addresses the control of osteoblast differentiation and the generation of genetic resources to advance this research.
- Effect of loading on bone development early in life. Bone mass during adult life reflects the amount acquired during growth minus that which is subsequently lost. Thus, maximizing peak bone mass may provide an effective strategy to prevent osteoporosis. Two hundred prepubescent children are participating in a study to determine the impact of jumping, a high weight-bearing exercise, on the development of bone mass. The study may show that implementing a specific bone-loading program during childhood will enhance the development of both bone mass and mineralization at an earlier age. This would provide a larger foundation for mineralization and growth through adolescence, thereby reducing the risk of future osteoporotic fractures.
- Genetic analysis of bone mass. Although lifestyle and environmental factors play a role, up to 75 percent of bone mineral density is genetically determined. Researchers are employing a new method of mapping genes that influence continuously varying traits, such as bone mass. In mouse experiments, researchers have identified 17 candidate genes that may influence the development of peak bone mass during skeletal growth. The mapping of risk and protective genes in mice and the development of unique animal models for isolating the effects of those genes offer an important route to the possible identification of risk and protective genes in humans. This would allow prediction of individual rather than general risk, which, in turn, could lead to effective targeting of prevention-based treatment strategies to high-risk populations.
- Understanding the molecular pathways that mediate PTH. Intermittently administered parathyroid hormone (PTH) can stimulate increases in bone mass. Although practical problems may limit the use of PTH in this way, current research on the molecular pathways that mediate PTH action may make it possible to derive a similar beneficial effect in other ways.