Department of Normal Physiology, Danylo Halytsky Lviv National Medical University, Lviv, Ukraine.
Department of Toxicological and Analytical Chemistry, Danylo Halytsky Lviv National Medical University, Lviv, Ukraine.
Endocr Regul. 2021 Jan 29;55(1):42-51. doi: 10.2478/enr-2021-0006.
Clinical use of glucocorticoids is a frequent cause of secondary osteoporosis, which reduces the mineral density of bones and results in pathological fractures. Mechanical stimulation as non-physiological high-frequency vibration with low acceleration prevents the loss of a crystalline component and stimulates the anabolic remodeling of the bone. The aim of the present research was to assess the impact of mechanical vibration on the bone structure in rats, which received glucocorticoids. Wistar rats were randomized into three groups: Vehicle control (Veh), Methylprednisolone sodium succinate (Mps), and Mps combined with whole-body vibration (WBV). Rats of Mps+WBV and Mps groups received 3 mg/kg/day of methylprednisolone every other day for 24 weeks and rats of Veh group received 0.9% saline (sodium chloride). The group of rats Mps+WBV was subjected to WBV for 30 minutes per day for five days a week with parameters 0.3 g and frequency 50 Hz. Relative amount of crystalline component and collagen in the bones was determined by X-ray diffraction (XRD) and calcium level - by atomic absorption spectroscopy. Bone tissue metabolism was assessed by determining the concentration of markers, in particular osteocalcin and Tartrate-resistant acid phosphatase (TRAP5b). Glucocorticoids induced a considerable increase in the rats body mass (+13%) and decreased the content of mineral component in the femoral neck (-17%) in Mps group compared with Veh. The process of the bone metabolism was significantly accelerated, which is proven by an increased level of remodeling markers. It should be mentioned that WBV did not allow significant decrease in mineral component of the bone to 16th week of the experiment compared with Mps group, although these parameters did not achieve the indices in the Vehicle control group (-10%). Our investigation allows to suggest that mechanical high-frequency vibration of low intensity can partially inhibit the harmful consequences of glucocorticoids on bone structure in rats. Despite the positive impact of vibration on the bone tissue after Mps introduction in the 8th-16th week, this influence was not statistically reliable in the 24th week of the experiment. The results of our investigation on animal model indicate that non-physiological vertical mechanical vibrations are an effective means to prevent loss of a mineral bone component during treatment with glucocorticoids.
临床使用糖皮质激素是导致继发性骨质疏松症的常见原因，它会降低骨骼的矿物质密度，导致病理性骨折。机械刺激作为一种非生理的高频低加速度振动，可以防止晶体成分的丢失，并刺激骨骼的合成代谢重塑。本研究旨在评估机械振动对接受糖皮质激素治疗的大鼠骨骼结构的影响。Wistar 大鼠随机分为三组：Vehicle 对照组（Veh）、甲泼尼龙琥珀酸钠（Mps）和甲泼尼龙琥珀酸钠联合全身振动（WBV）组。Mps+WBV 和 Mps 组大鼠每隔一天接受 3mg/kg/天的甲泼尼龙，共 24 周，Veh 组大鼠接受 0.9%生理盐水（氯化钠）。Mps+WBV 组大鼠每天接受 30 分钟全身振动，每周 5 天，参数为 0.3g，频率为 50Hz。通过 X 射线衍射（XRD）和原子吸收光谱法测定骨中结晶成分和胶原的相对含量。通过测定标记物（特别是骨钙素和抗酒石酸酸性磷酸酶 5b（TRAP5b））的浓度来评估骨组织代谢。与 Veh 组相比，Mps 组大鼠的体重显著增加（增加 13%），股骨颈的矿物质含量减少（减少 17%），这表明骨代谢过程明显加快。值得注意的是，与 Mps 组相比，在实验的第 16 周，WBV 并没有使骨的矿物质含量显著下降到 16 周，尽管这些参数没有达到 Veh 对照组的指标（下降 10%）。我们的研究表明，低强度的高频机械振动可以部分抑制糖皮质激素对大鼠骨骼结构的有害影响。尽管在引入 Mps 后的第 8-16 周振动对骨骼组织有积极影响，但在实验的第 24 周，这种影响在统计学上并不可靠。我们在动物模型上的研究结果表明，非生理垂直机械振动是预防糖皮质激素治疗过程中矿物质骨成分丢失的有效手段。
