bd-xu 2020-04-17 907

Scientific Reports丨Dried sour plum also has a miraculous effect: it can slow down the symptoms of osteoporosis in space flight

    在地球上，骨骼内平衡是通过控制成骨细胞的形成和吸收来维持的。然而，太空飞行作为一种独特的环境，它包含了至少两个对骨骼健康有负面影响的因素:微重力和电离辐射。当人体暴露于低辐射(137 Cs或X射线，1-2 Gy射线)会容易导致骨折或者骨质疏松症状。
    4月16日，美国国家航空航天局艾姆斯研究中心空间生物科学部的Ruth K. Globus和Ann-Sofie Schreurs教授及其团队在Scientific Reports上发表题为Dietary countermeasure mitigates simulated spaceflight-induced osteopenia in mice的研究论文，探究了饮食中添加酸梅干可以缓解模拟太空飞行引起的小鼠骨质疏松症状，验证了喂食酸梅干对模拟微重力和电离辐射的独立和联合作用对骨骼组织的微观结构和力学性能的保护作用。

  The experimental team designed the control diet group (CD) and the dried plum group (DP) two groups (including: untreated group (NL), X-ray (HU) treatment group, infrared (IR) treatment group or HU+IR treatment group ), 10 mice in each group; the control diet group (CD) and the dried plum group (DP) were exposed to a simulated space flight environment (HU, IR, or a combination of both), and then through micro-computed tomography ( microCT) to quantify the differences in bone microstructure after treatment in each group, and analyzed the cancellous and cortical areas of the appendicular skeleton (ie, tibia) and the axial skeleton (ie, spine).

  In the appendage bone analysis, the tibial cancellous microstructure of the mice fed the dried plum group had no obvious defects compared with the untreated mice, while the mice in the diet group showed structural defects of the cancellous microstructure. Exposure of mice in the diet control group to a simulated space flight environment will cause the trabecular bones to become thinner, the separation will increase, and the parameters of the cancellous bone cavity will decrease significantly. In the mice fed the dried plum group, except for the combined treatment of HU and IR, the thickness of the trabecular bone of the mouse was significantly reduced. Other data indicated that the fed dried plum had radiation protection to the cancellous bone and trabecular bone of the mouse. effect. In the axial bone analysis, compared with the mice in the diet group, feeding the dried plum group can prevent the loss of cancellous and cortical bone in the L4 vertebrae.

Simulate the loss of bone in the cancellous and cortical areas of the appendage bones caused by space flight

Coronal CT image and three-dimensional structure of cancellous bone in tibia after simulated space flight

Simulate the loss of bone in the cancellous and cortical areas of the axial skeleton after spaceflight

  Next, the experimental team performed a single compression test on the L4 vertebrae of the two groups of mice to determine the difference in mechanical properties of bone tissue. Compared with the untreated mice, the simulated microgravity environment reduced the vertebral strength of the mice in the control diet group, while the vertebral strength of the mice fed the dried plum group was protected. It is proved that feeding dried plums can protect bone cells from simulated microgravity damage, and effectively prevent the decline of bone microstructure and mechanical properties caused by unloading of hind limbs and simulated space flight.

 

Differences in vertebral compressive strength after simulated space flight

  In addition, the research team washed the bone marrow cells of untreated mice and HU-treated mice from the femur and cultivated them in osteoblast culture medium to differentiate the cells into osteoblasts and quantify the differentiation and growth of osteoblasts. area. The experimental results show that compared with untreated mice, the diet-controlled mice have a sharp decrease in cell growth area after treatment with HU; in contrast, the formation and growth area of osteoblast colonies in mice fed the dried plum group There is no reduction. It showed that feeding dried plums had protective effects on HU-induced proliferation and differentiation of mouse osteoblasts.

Feeding dried plums can prevent HU-induced osteoblast loss in vitro
Finally, researchers have shown that dried plums serve as a potential countermeasure against osteoporosis caused by radiation and microgravity (such as loss of tibia and vertebral bone strength and structure), astronauts, radiation workers, radiotherapy patients and bone Patients with porosis are of great significance.
▎Reference: https://doi.org/10.1038/s41598-020-63404-x