Beneficial Effects of a Flavonoid Fraction of Herba Epimedii on Bone Metabolism in Ovariectomized Rats

Abstract

A flavonoid fraction of Herba Epimedii, including eight flavonoid glycoside compounds, epimedoside A, ikarisoside F, baohuoside II, sagittatoside A, sagittatoside B, 7-O-rhamnosyl icariside II, 2"-O-rhamnosyl icariside II, and baohuoside I, was isolated and prepared from the leaves of Herba Epimedii. This study was conducted to assess the potential effect of the flavonoid fraction of Herba Epimedii on osteoporosis in ovariectomized rats. Rats received repeated administration of a vehicle (ovariectomized), the flavonoid fraction of Herba Epimedii (7.5, 15, 30 mg/kg/d), and ipriflavone (200 mg/kg/d) once a day for 8 weeks, beginning 4 weeks after ovariectomization. Then, the bone turnover markers, bone biomechanical properties, trabecular architecture, and related protein expressions were evaluated by biochemical assay kits, mechanical testing, microcomputed tomography, immunohistochemical evaluation, and Western blot analysis. Treatment with the flavonoid fraction of Herba Epimedii (15, 30 mg/kg/d) and ipriflavone (200 mg/kg/d) significantly increased bone strength while dramatically inhibiting the serum alkaline phosphatase and tartrate-resistant acid phosphatase levels in ovariectomized rats. Furthermore, the flavonoid fraction of Herba Epimedii also increased osteoprotegerin protein expression and reduced the receptor activator of nuclear factor-κB ligand protein expression compared with ovariectomized rats. In addition, the microcomputed tomography results showed that the flavonoid fraction of Herba Epimedii treatment significantly improved trabecular bone mineral density and restored the bone microarchitecture in ovariectomized rats. Therefore, our results indicated that the flavonoid fraction of Herba Epimedii might be beneficial for improving postmenopausal osteoporosis and should be considered as a promising candidate for treating postmenopausal osteoporosis.

Chinese single herbs and active ingredients for postmenopausal osteoporosis: From preclinical evidence to action mechanism

“…FE increased OPG protein expression and reduced the RANKL protein expression in OVX rats (18). Icariin increased the mRNA expression ratio of OPG/RANKL, up-regulated mRNA expression of low-density lipoprotein receptorrelated protein 6 (Lrp6) receptor, while it downregulated glycogen synthase kinase-3β and Runx2, following OVX (24,25).…”

“…bone alkaline phosphatase (BALP), decreased serum osteocalcin and ALP activity, decreased C-terminal telopeptide of type I collagen (CTX) levels compared with the OVX group (15)(16)(17). Flavonoid fraction of Epimedium (FE), ipriflavone, and anhydroicaritin inhibited serum ALP and TRAP in OVX rats (18).…”

Beneficial Effects and Toxicity Studies of Xian-ling-gu-bao on Bone Metabolism in Ovariectomized Rats

“…Bone mineral density, which is an important marker for bone strength, serves as a basis to predict the risk of fracture (Zhao et al, 2016). The trabecular bone is the extension of the cortex, and it is used as the golden standard to diagnose osteoporosis.…”

Osteoprotective Medicinal Plants - Part 1 (A Human Clinical Evidence-Based Review)

“…Icariin, one of the mentioned compounds, has been proved to have multitarget antiosteoporotic activity, with simultaneous promotion of osteoblastogenesis, inhibition of adipogenesis, and prevention of osteoclast differentiation, in animal studies (Xue et al, 2016). Besides icariin, flavonoid fraction of Epimedium is also osteo-active, improving trabecular BMD and restoring the bone microarchitecture in OVX-R (Zhao et al, 2016). A study of systems pharmacology predicted that Epimedium phytochemicals may exert its benefits on bone health by direct regulation of several osteoporosis related targets, via estrogen like mechanisms (Xu et al, 2016).…”