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Osteoporosis: HELP
Articles by Jean D. Sibonga
Based on 5 articles published since 2010
(Why 5 articles?)

Between 2010 and 2020, J. Sibonga wrote the following 5 articles about Osteoporosis.
+ Citations + Abstracts
1 Review Spaceflight-induced bone loss: is there an osteoporosis risk? 2013

Sibonga, Jean D. ·NASA Johnson Space Center, 2101 NASA Parkway, Houston, TX 77058, USA. Jean.sibonga-1@NASA.gov ·Curr Osteoporos Rep · Pubmed #23564190.

ABSTRACT: Currently, the measurement of areal bone mineral density (aBMD) is used at NASA to evaluate the effects of spaceflight on the skeletal health of astronauts. Notably, there are precipitous declines in aBMD with losses >10 % detected in the hip and spine in some astronauts following a typical 6-month mission in space. How those percentage changes in aBMD relate to fracture risk in the younger-aged astronaut is unknown. Given the unique set of risk factors that could be contributing to this bone loss (eg, adaptation to weightlessness, suboptimal diet, reduced physical activity, perturbed mineral metabolism), one might not expect skeletal changes due to spaceflight to be similar to skeletal changes due to aging. Consequently, dual-energy X-ray absorptiometry (DXA) measurement of aBMD may be too limiting to understand fracture probability in the astronaut during a long-duration mission and the risk for premature osteoporosis after return to Earth. Following a brief review of the current knowledge-base, this paper will discuss some innovative research projects being pursued at NASA to help understand skeletal health in astronauts.

2 Article Resistive exercise in astronauts on prolonged spaceflights provides partial protection against spaceflight-induced bone loss. 2019

Sibonga, J / Matsumoto, T / Jones, J / Shapiro, J / Lang, T / Shackelford, L / Smith, S M / Young, M / Keyak, J / Kohri, K / Ohshima, H / Spector, E / LeBlanc, A. ·Human Health & Performance Directorate, NASA Johnson Space Center, 2101 NASA Parkway, Houston, TX 77058, USA. Electronic address: jean.sibonga-1@nasa.gov. · Fujii Memorial Institute of Medical Sciences, University of Tokushima, Tokushima 770-8503, Japan. Electronic address: toshio.matsumoto@tokushima-u.ac.jp. · Center for Space Medicine, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA. Electronic address: jajones@bcm.edu. · Department of Medicine, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA. Electronic address: jayrshapiro@gmail.com. · Department of Radiology, University of California, San Francisco, CA 94143, USA. Electronic address: thomas.lang@ucsf.edu. · Human Health & Performance Directorate, NASA Johnson Space Center, 2101 NASA Parkway, Houston, TX 77058, USA. Electronic address: linda.c.shackelford@nasa.gov. · Human Health & Performance Directorate, NASA Johnson Space Center, 2101 NASA Parkway, Houston, TX 77058, USA. Electronic address: scott.m.smith@nasa.gov. · Human Health & Performance Directorate, NASA Johnson Space Center, 2101 NASA Parkway, Houston, TX 77058, USA. Electronic address: millennia.young@nasa.gov. · Department of Radiological Sciences, Department of Mechanical and Aerospace Engineering, Department of Biomedical Engineering, University of California, Irvine, CA 92697, USA. Electronic address: jhkeyak@uci.edu. · Department of Nephrology, Nagoya City University, Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya 467-8601, Japan. Electronic address: kohri@med.nagoya-cu.ac.jp. · Japan Aerospace Exploration Agency, Tsukuba Space Center, 2-1-1 Sengen, Tsukuba-Shi, Ibaraki 305-8505, Japan. Electronic address: ohshima.hiroshi2@jaxa.jp. · KBRwyle, 2400 NASA Parkway, Houston, TX 77058, USA. Electronic address: elisabeth.r.spector@nasa.gov. · Center for Space Medicine, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA. Electronic address: adleblanc2@gmail.com. ·Bone · Pubmed #31400472.

ABSTRACT: Bone loss in astronauts during spaceflight may be a risk factor for osteoporosis, fractures and renal stone formation. We previously reported that the bisphosphonate alendronate, combined with exercise that included an Advanced Resistive Exercise Device (ARED), can prevent or attenuate group mean declines in areal bone mineral density (aBMD) measured soon after ~ 6-month spaceflights aboard the International Space Station (ISS). It is unclear however if the beneficial effects on postflight aBMD were due to individual or combined effects of alendronate and ARED. Hence, 10 additional ISS astronauts were recruited who used the ARED (ARED group) without drug administration using similar measurements in the previous study, i.e., densitometry, biochemical assays and analysis of finite element (FE) models. In addition densitometry data (DXA and QCT only) were compared to published data from crewmembers (n = 14-18) flown prior to in-flight access to the ARED (Pre-ARED). Group mean changes from preflight (± SD %) were used to evaluate effects of countermeasures as sequentially modified on the ISS (i.e., Pre-ARED vs. ARED; ARED vs. Bis+ARED). Spaceflight durations were not significantly different between groups. Postflight bone density measurements were significantly reduced from preflight in the Pre-ARED group. As previously reported, combined Bis+ARED prevented declines in all DXA and QCT hip densitometry and in estimates of FE hip strengths; increased the aBMD of lumbar spine; and prevented elevations in urinary markers for bone resorption during spaceflight. ARED without alendronate partially attenuated declines in bone mass but did not suppress biomarkers for bone resorption or prevent trabecular bone loss. Resistive exercise in the ARED group did not prevent declines in hip trabecular vBMD, but prevented reductions in cortical vBMD of the femoral neck, in FE estimate of hip strength for non-linear stance (NLS) and in aBMD of the femoral neck. We conclude that a bisphosphonate, when combined with resistive exercise, enhances the preservation of bone mass because of the added suppression of bone resorption in trabecular bone compartment not evident with ARED alone.

3 Article Evaluating Bone Loss in ISS Astronauts. 2015

Sibonga, Jean D / Spector, Elisabeth R / Johnston, Smith L / Tarver, William J. ·NASA Johnson Space Center and Wyle Science, Technology and Engineering Group, Houston, TX, USA. ·Aerosp Med Hum Perform · Pubmed #26630194.

ABSTRACT: INTRODUCTION: The measurement of bone mineral density (BMD) by dual-energy X-ray absorptiometry (DXA) is the Medical Assessment Test used at the NASA Johnson Space Center to evaluate whether prolonged exposure to spaceflight increases the risk for premature osteoporosis in International Space Station (ISS) astronauts. The DXA scans of crewmembers' BMD during the first decade of the ISS existence showed precipitous declines in BMD for the hip and spine after the typical 6-mo missions. However, a concern exists that skeletal integrity cannot be sufficiently assessed solely by DXA measurement of BMD. Consequently, use of relatively new research technologies is being proposed to NASA for risk surveillance and to enhance long-term management of skeletal health in long-duration astronauts. Sibonga JD, Spector ER, Johnston SL, Tarver WJ. Evaluating bone loss in ISS astronauts.

4 Article Acute exposure to high dose γ-radiation results in transient activation of bone lining cells. 2013

Turner, Russell T / Iwaniec, Urszula T / Wong, Carmen P / Lindenmaier, Laurence B / Wagner, Lindsay A / Branscum, Adam J / Menn, Scott A / Taylor, James / Zhang, Ye / Wu, Honglu / Sibonga, Jean D. ·Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, OR, USA; Center for Healthy Aging Research, Oregon State University, Corvallis, OR, USA. Electronic address: Russell.Turner@oregonstate.edu. ·Bone · Pubmed #23954507.

ABSTRACT: The present studies investigated the cellular mechanisms for the detrimental effects of high dose whole body γ-irradiation on bone. In addition, radioadaptation and bone marrow transplantation were assessed as interventions to mitigate the skeletal complications of irradiation. Increased trabecular thickness and separation and reduced cancellous bone volume fraction, connectivity density, and trabecular number were detected in proximal tibia and lumbar vertebra 14days following γ-irradiation with 6Gy. To establish the cellular mechanism for the architectural changes, vertebrae were analyzed by histomorphometry 1, 3, and 14days following irradiation. Marrow cell density decreased within 1day (67% reduction, p<0.0001), reached a minimum value after 3days (86% reduction, p<0.0001), and partially rebounded by 14days (30% reduction, p=0.0025) following irradiation. In contrast, osteoblast-lined bone perimeter was increased by 290% (1day, p=0.04), 1230% (3days, p<0.0001), and 530% (14days, p=0.003), respectively. There was a strong association between radiation-induced marrow cell death and activation of bone lining cells to express the osteoblast phenotype (Pearson correlation -0.85, p<0.0001). An increase (p=0.004) in osteoclast-lined bone perimeter was also detected with irradiation. A priming dose of γ-radiation (0.5mGy), previously shown to reduce mortality, had minimal effect on the cellular responses to radiation and did not prevent detrimental changes in bone architecture. Bone marrow transplantation normalized marrow cell density, bone turnover, and most indices of bone architecture following irradiation. In summary, radiation-induced death of marrow cells is associated with 1) a transient increase in bone formation due, at least in part, to activation of bone lining cells, and 2) an increase in bone resorption due to increased osteoclast perimeter. Bone marrow transplantation is effective in mitigating the detrimental effects of acute exposure to high dose whole body γ-radiation on bone turnover.

5 Article Bisphosphonates as a supplement to exercise to protect bone during long-duration spaceflight. 2013

Leblanc, A / Matsumoto, T / Jones, J / Shapiro, J / Lang, T / Shackelford, L / Smith, S M / Evans, H / Spector, E / Ploutz-Snyder, R / Sibonga, J / Keyak, J / Nakamura, T / Kohri, K / Ohshima, H. ·Universities Space Research Association, 3600 Bay Area Blvd, Houston, TX 77058, USA. leblanc@dsls.usra.edu ·Osteoporos Int · Pubmed #23334732.

ABSTRACT: INTRODUCTION: This investigation was an international collaboration between NASA and the JAXA space agencies to investigate the potential value of antiresorptive agents to mitigate the well-established bone changes associated with long-duration spaceflight. METHODS: We report the results from seven International Space Station (ISS) astronauts who spent a mean of 5.5 months on the ISS and who took an oral dose of 70 mg of alendronate weekly starting 3 weeks before flight and continuing throughout the mission. All crewmembers had available for exercise a treadmill, cycle ergometer, and a resistance exercise device. Our assessment included densitometry of multiple bone regions using X-ray absorptiometry (DXA) and quantitative computed tomography (QCT) and assays of biomarkers of bone metabolism. RESULTS: In addition to pre- and post-flight measurements, we compared our results to 18 astronauts who flew ISS missions and who exercised using an early model resistance exercise device, called the interim resistance exercise device, and to 11 ISS astronauts who exercised using the newer advanced resistance exercise device (ARED). Our findings indicate that the ARED provided significant attenuation of bone loss compared with the older device although post-flight decreases in the femur neck and hip remained. The combination of the ARED and bisphosphonate attenuated the expected decline in essentially all indices of altered bone physiology during spaceflight including: DXA-determined losses in bone mineral density of the spine, hip, and pelvis, QCT-determined compartmental losses in trabecular and cortical bone mass in the hip, calculated measures of fall and stance computed bone strength of the hip, elevated levels of bone resorption markers, and urinary excretion of calcium. CONCLUSIONS: The combination of exercise plus an antiresoptive drug may be useful for protecting bone health during long-duration spaceflight.