杨梅素减轻去卵巢大鼠骨质疏松

Effect of myricetin on alleviating osteoporosis in ovariectomized rats

目的观察杨梅素对去卵巢大鼠骨量的影响,初步探讨机制。方法 12只雌性SD大鼠随机分为假手术组、去卵巢组(OVX)和杨梅素注射组(OVX+Myricetin)。建模后1周,OVX+Myricetin组、假手术组和OVX组分别腹腔注射杨梅素85 mg/kg和甲醇溶剂,2次/周,8周。取材前10 d和前3 d分别皮下注射茜素红。micro CT扫描股骨远心端。HE染色观察骨小梁。Elisa检测血清PINP浓度。荧光显微镜观察茜素红荧光条带。ALP染色检测BMMSCs成骨能力。荧光标记法检测BMMSCs活性氧水平。Real-time PCR检测基因表达。结果 OVX组的骨量/组织量(BV/TV)、骨小梁数量(Tb.N)和骨小梁厚度(Tb.Th)低于假手术组;骨小梁间隙(Tb.Sp)大于假手术组,HE切片OVX组的骨小梁少于假手术组,OVX组的血清PINP、茜素红荧光条带间距低于假手术组。OVX+Myricetin组的BV/TV、Tb.N和Tb.Th大于OVX组;Tb.Sp小于OVX组,HE切片OVX+Myricetin组的骨小梁多于OVX组,OVX+Myricetin组的血清PINP、茜素红荧光条带间距高于OVX组。OVX组BMMSCs的ROS水平高于假手术组,SOD表达降低,ALP活性和成骨基因表达降低;OVX+Myricetin组低于OVX组,SOD表达升高,ALP活性和成骨基因表达升高。H_2O_2处理后的BMMSCs的ROS水平升高,SOD表达降低,ALP活性和成骨基因表达降低;加杨梅素处理后的BMMSCs的ROS水平降低,SOD表达升高,ALP活性和成骨基因表达升高。结论杨梅素通过降低ROS水平恢复内源性BMMSCs的成骨能力,减少去卵巢大鼠骨量丢失。

Objective To observe the effect of myricetin on bone volume of ovariectomized （OVX） rats and primarily explore the mechanism. Methods Twelve female SD rats were randomly divided into sham group, OVX group and OVX ＋ myricetin group. In 1 week after modeling, the OVX ＋ myricetin group, sham group and OVX group were intraperitoneally injected with myricetin 85 mg/kg or methanol solvent, twice per week, for 8 weeks. Subcutaneous injection of alizarin red was conducted on the 10th day and 3rd day before the rats were sacrificed. Distal femurs were analyzed by MicroCT scanning. Trabecular bone （Tb） was tested by HE staining. Serum amino-terminal propeptide of type I procollagen （PINP） was detected by ELISA. Alizarin red fluorescent strips were observed with fluorescence microscopy. Osteogenesis of BMMSCs was analyzed by ALP staining. ROS level was detected by fluorescence tagging. Gene expression was tested by real-time PCR. Results The bone volume/tissue volume （BV/T~）, Tb number and Tb thickness of theOVX group were lower than those of the sham group, whereas the Tb space was higher. Tb of the OVX group was less than that of the sham group. Serum PINP and the distance between two alizarin red fluorescent strips in the OVX group were lower than those in the sham group. BV/TV, Tb number and Tb thickness of the OVX ＋ myricetin group were higher than those of the OVX group, whereas Tb space was lower. Tb of the OVX ＋ myricetin group was more than that of the OVX group. Serum PINP and the distance between two alizarin red fluorescent strips in the OVX ＋ myricetin group were higher than those in the OVX group. The ROS level of endogenous BMMSCs in the OVX group was higher than that in the sham group, the expression of SOD was lower, and ALP activity and osteogenic genes were higher. ROS level of endogenous BMMSCs in the OVX ＋ myricetin group was lower than that of the OVX group, the expression of SOD was higher, and ALP activity and osteogenic genes were lower. Furthermore, ROS level of H202-treated BMMSCs was higher than that of non-treated BMMSCs, the expression of SOD was lower, and ALP activity and osteogenic genes were higher ROS level of H2O2 -treated BMMSCs declined after treatment with myricetin, the expression of SOD was higher, and ALP activity and osteogenic genes were lower. Conclusion rats through lowering endogenous ROS level and restoring osteogenesis of Myricetin reduces bone loss of OVX endogenous BMMSCs.