Department of Pharmacology, School of Pharmacy, China Medical University, Shenyang, China.
Department of Pharmacology, School of Pharmacy, China Medical University, Shenyang, China; Liaoning Key Laboratory of Molecular Targeted Anti-Tumor Drug Development and Evaluation, Shenyang, China.
Phytomedicine. 2022 Jul 20;102:154198. doi: 10.1016/j.phymed.2022.154198. Epub 2022 May 21.
Postmenopausal osteoporosis (PMOP) is a serious problem for the women over 50 years old. Natural product puerarin (PUE) has been proven to improve PMOP with high safety. PMOP is a metabolic disorder affecting bone metabolism, indicating that endogenous metabolites amelioration may be a novel strategy for PMOP therapy. However, what the metabolic profile of POMP will be after PUE treatment is still obscure.
We purpose to figure out the metabolic characteristics of PMOP and to explore the intrinsic mechanism on the anti-osteoporosis efficacy after PUE treatment based on the serum metabolomics.
We established OVX rats as osteoporosis model, and the animals were distributed into Sham, OVX, and OVX+PUE (100 mg/kg/d) group. The femurs were analyzed by μ-CT and three-point bending test. Serum metabolomics was performed by UPLC/Q-TOF-MS. We also determined the body weight, liver weight, and the levels of serum TC, TG, LDL-C, and HDL-C. The key proteins of the PPARγ pathway and Wnt pathway were analyzed by Western blot and qPCR experiments.
PUE treatment for 14 weeks both improved the bone structure and ameliorated lipid metabolism in ovariectomized rats. By determination and further analysis of serum metabolomics, we revealed that the endogenous metabolites was significantly changed in ovariectomized rats, and PUE treatment adjusted 23 differential metabolites, which were involved in phospholipid metabolism metabolism and PUFAs metabolic pathways. Close correlationships were futher found between the indexes of bone metabolism, lipid metabolism and the differential metabolites, particularly LysoPA, S1P and n-3/n-6 PUFAs. Further, we discovered that PUE regulated differentiation of BMSCs to elicit anti-osteoporosis efficacy, attributing to Wnt/β-catenin signaling activation and PPARγ pathway inhibition initiated by metabolomics.
PUE improves OVX-induced osteoporosis and lipid metabolism by regulating phospholipid metabolism and biosynthesis of PUFAs, resulting in reducing the adipogenic differentiation and promoting osteogenic differentiation of BMSCs via Wnt pathway activation and PPARγ pathway inhibition in ovariectomized rats. The study provides us a novel mechanism to explain the improvement of osteoporosis by PUE, depicts a metabolic profile of PMOP, and gives us another point cut for further exploring the pathogenesis of PMOP and looking for biomarkers of osteoporosis.
绝经后骨质疏松症（PMOP）是 50 岁以上女性的严重问题。天然产物葛根素（PUE）已被证明可安全有效地治疗 PMOP。PMOP 是一种影响骨代谢的代谢紊乱，表明内源性代谢物的改善可能是 PMOP 治疗的新策略。然而，PUE 治疗后 POMP 的代谢谱会如何仍然不清楚。
我们旨在通过血清代谢组学研究，找出 PMOP 的代谢特征，并探讨 PUE 治疗后抗骨质疏松疗效的内在机制。
我们建立了去卵巢大鼠骨质疏松模型，将动物分为假手术组、去卵巢组和去卵巢+PUE（100mg/kg/d）组。用 μ-CT 和三点弯曲试验分析股骨。采用 UPLC/Q-TOF-MS 进行血清代谢组学分析。还测定了体重、肝重和血清 TC、TG、LDL-C 和 HDL-C 水平。采用 Western blot 和 qPCR 实验分析 PPARγ 通路和 Wnt 通路的关键蛋白。
PUE 治疗 14 周可改善去卵巢大鼠的骨结构和脂质代谢。通过测定和进一步分析血清代谢组学，我们发现去卵巢大鼠的内源性代谢物明显改变，PUE 治疗调节了 23 种差异代谢物，这些代谢物涉及磷脂代谢和多不饱和脂肪酸代谢途径。进一步发现骨代谢、脂质代谢和差异代谢物之间存在密切相关性，特别是溶血磷脂酸、S1P 和 n-3/n-6 多不饱和脂肪酸。此外，我们发现 PUE 通过代谢组学调节 BMSCs 的分化来发挥抗骨质疏松作用，这归因于 Wnt/β-catenin 信号的激活和 PPARγ 通路的抑制。
PUE 通过调节磷脂代谢和多不饱和脂肪酸的生物合成，改善去卵巢大鼠引起的骨质疏松症和脂质代谢，通过激活 Wnt 通路和抑制 PPARγ 通路减少骨髓间充质干细胞的成脂分化，促进其成骨分化。该研究为我们提供了一种新的机制来解释 PUE 改善骨质疏松症的作用，描绘了 PMOP 的代谢特征，并为我们进一步探索 PMOP 的发病机制和寻找骨质疏松症的生物标志物提供了另一个切入点。
