칼슘과 비타민 D 복용이 뼈 건강 및 골다공증 예방에 미치는 영향

Research Summary & Abstract: Osteoporosis is a global degenerative bone disorder in the elderly caused by the aging of bone and immune systems. Current therapeutics for osteoporosis focus on medical control over the osteoblast and osteoclast, resulting in complicated procedures and side effects. Regulation of osteoimmunity is of high significance for biocompatible and effective osteoporosis treatment. In the present work, we have designed a strontium phosphate (SP)-coated hollow zeolitic imidazolate framework-8 (hZIF) nanomedicine by chemical mineralization in which vitamin D3 (VD) has been further encapsulated. The formulated VD@SP-hZIF nanoparticles exhibit robust osteoimmune-regulative effects (anti-inflammatory, pro-osteogenesis, and calcium absorption promotion) in aged murine osteoporotic models respectively due to the constructed moieties of zinc ions, strontium phosphates and the loaded VD. The in-depth osteoporotic therapeutic mechanism of VD@SP-hZIF nanoparticles has also been explored. The present work highlights the construction of the metal-organic framework nanomedicines for effective regulation of osteoimmune microenvironment against osteoporosis, providing a highly applicable therapeutic paradigm towards pathologies with inflammatory disorders.

Research Summary & Abstract: Dietary supplementation of calcium and vitamin D has been deemed one of the most important tools to fight against osteoporotic fractures increasing with aging of the population globally. Reports from early clinical trials demonstrated that supplementation of calcium and vitamin D for patients with osteoporosis can reduce the incidence of fragility fractures by decreasing bone loss and falls. However, following trials failed to demonstrate the efficacy of calcium and vitamin D for the prevention of osteoporotic fractures, questioning the need of calcium and vitamin D supplementation. Even metanalyses and system reviews presented opposite conclusions , depending on clinical trials included. Recent studies reported that excessive calcium supplement can increase cardiovascular risk such as non-fatal myocardial infarction and that excessive vitamin D supplement can produce more frequent falls than it is supposed to be. However, in spite of some arguments regarding the efficacy and safety of calcium and vitamin D supplementation, it seems to be essential to provide 800 to 1,000 mg elementary calcium and 800 to 1,000 IU vitamin D for the elderly whose intake of calcium and vitamin D is insufficient to prevent osteoporotic fracture.

Research Summary & Abstract: Purpose: Tamoxifen and aromatase inhibitor (AI) are used for hormone therapy for hormone-positive breast cancer, and AI is well known to decrease bone mineral density (BMD). The authors compared the serial BMD of patients with hormone-positive breast cancer to evaluate the preventive effect of AI combined with calcium and vitamin D (Ca/Vit D) supplements. Methods: A total of 249 women with hormone-positive breast cancer who underwent serial BMD assessments between 2011 and 2015 were included. The patients were classified as the tamoxifen alone group (n=23), AI with Ca/Vit D group (n=139), and extended regimen from tamoxifen to AI with Ca/Vit D group (n=87). Moreover, osteoporosis was diagnosed based on the World Health Organization guideline. Results: The incidence of osteoporosis was highest in the AI with Ca/Vit D group (n=50, 36.0%) and lowest in the tamoxifen only group (n=4, 17.4%). Furthermore, it showed statistical difference between the three groups (p=0.003). However, considering the baseline of initial BMD in each patient, the mean change value did not show any statistical difference between the three groups (p=0.498). Moreover, the lumbar T-scores were lower than that of the total hip T-scores in each patient. Conclusion: Although it has been reported that osteoporosis is common in patients treated with AI, the decreased BMD was not significantly severe compared to that in the tamoxifen alone group if Ca/Vit D was administrated with AI. Therefore, Ca/Vit D has some preventive effect for osteoporosis in patients treated with AI.