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Shapiro, J.

Publications and source records attributed to Shapiro, J..

5 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2015

Update of Bisphosphonate Flight Experiment

Elevated bone resorption is a hallmark of human spaceflight and bed rest indicating that elevated remodeling is a major factor in the etiology of space flight bone loss. In a collaborative effort between the NASA and JAXA space agencies, we are testing whether an antiresorptive drug would provide additional benefit to in-flight exercise to ameliorate bone loss and hypercalciuria during long-duration spaceflight. Measurements of bone loss include DXA, QCT, pQCT, urinary and blood biomarkers. We have completed analysis of R+1year data from 7 crewmembers treated with alendronate during flight, as well as immediate post flight (R+<2wks) data from 6 of 10 concurrent controls without treatment. The treated astronauts used the Advanced Resistive Exercise Device (ARED) during their missions. The purpose of this report is twofold: 1) to report the results of inflight, post flight and one year post flight bone measures compared with available controls with and without the use of ARED; and 2) to discuss preliminary data on concurrent controls. The figure below compares the BMD changes in ISS crewmembers exercising with and without the current ARED protocol and the alendronate treated crewmembers also using the ARED. This shows that the use of ARED prevents about half the bone loss seen in early ISS crewmembers and that the addition of an antiresorptive provides additional benefit. Resorption markers and urinary Ca excretion are not impacted by exercise alone but are significantly reduced with antiresorptive treatment. Bone measures for treated subjects, 1 year after return from space remain at or near baseline. DXA data for the 6 concurrent controls using the ARED device are similar to DXA data shown in the figure below. QCT data for these six indicate that the integral data are consistent with the DXA data, i.e., comparing the two control groups suggests significant but incomplete improvement in maintaining BMD using the ARED protocol. Biochemical data of the concurrent control group await sample return and analysis. The preliminary conclusion is that an antiresorptive may be an effective adjunct to exercise during long-duration spaceflight.

LeBlanc, A.↗
NASA NTRS2011

Bisphosphonates as a Countermeasure to Space Flight Induced Bone Loss

This poster reviews the possibility of using Bisphosphonates to counter the bone loss that is experienced during space flight. The Hypothesis that is tested in this experiment is that the combined effect of anti-resorptive drugs plus in-flight exercise regimen will attenuate space flight induced loss in bone mass and strength and reduce renal stone risk. The experiment design, the status and the results are described.

LeBlanc, A.↗
NASA NTRS2009

Bisphosphonate as a Countermeasure to Space Flight-Induced Bone Loss

The purpose of this research is to determine whether anti-resorptive pharmaceuticals such as bisphosphonates, in conjunction with the routine in-flight exercise program, will protect ISS crewmembers from the regional decreases in bone mineral density and bone strength and the increased renal stone risk documented on previous long-duration space flights [1-3]. Losses averaged ~ 1 to 2 percent per month in such regions as the lumbar spine and hip. Although losses showed significant heterogeneity among individuals and between bones within a given subject, space flight-induced bone loss was a consistent finding. More than 90 percent of astronauts and cosmonauts on long-duration flights (average 171 days) aboard Mir and the ISS, had a minimum 5 percent loss in at least one skeletal site, 40 percent of them had a 10 percent or greater loss in at least one skeletal site, and 22 percent of the Mir cosmonauts experienced a 15 to 20 percent loss in at least one site. These losses occurred even though the crewmembers performed time-consuming in-flight exercise regimens. Moreover, a recent study of 16 ISS astronauts using quantitative computed tomography (QCT) demonstrated trabecular bone losses from the hip averaging 2.3 percent per month [4]. These losses were accompanied by significant losses in hip bone strength that may not be recovered quickly [5]. This rapid loss of bone mass results from a combination of increased and uncoupled remodeling, as demonstrated by increased resorption with little or no change in bone formation markers [6-7]. This elevated remodeling rate likely affects the cortical and trabecular architecture and may lead to irreversible changes. In addition to bone loss, the resulting hypercalciuria increases renal stone risk. Therefore, it is logical to attempt to attenuate this increased remodeling with anti-resorption drugs such as bisphosphonates. Success with alendronate was demonstrated in a bed rest study [8]. This work has been extended to space flight and two dosing regimens: 1) an oral dose of 70 mg of alendronate taken weekly during flight or 2) a single intravenous (IV) dose of 4 mg of zoledronic acid given several weeks before flight. Currently the study is focusing on the oral option because of NASA s safety concerns with the IV-administered drug. The protocol requests 10 male or female crewmembers on ISS flights of 90 days or longer. Controls are 16 previous ISS crewmembers with QCT scans of the hip performed by these same investigators. The primary outcome measure for this study is hip trabecular bone mineral density measured by QCT, but other measures of bone mass are performed including peripheral QCT (pQCT) and dual-energy x-ray absorptiometry. Serum and urinary bone markers and renal stone risk measured before, during, and after flight are included. Postflight data are currently being collected from 2 ISS crewmembers. Two additional crewmembers will return this spring after ~6-month missions. To date no untoward effects have been encountered.

Spector, Elisabeth↗