Effect of epimedium pubescen flavonoid on bone mineral status and bone turnover in male rats chronically exposed to cigarette smoke.
BACKGROUND
Epimedii herba is one of the most frequently used herbs in formulas that are prescribed for the treatment of osteoporosis in China and its main constituent is Epimedium pubescen flavonoid (EPF). However, it is unclear whether EPF during chronic exposure to cigarette smoke may have a protective influence on the skeleton. The present study investigated the effect of EPF on bone mineral status and bone turnover in a rat model of human relatively high exposure to cigarette smoke.


METHODS
Fifty male Wistar rats were randomized into five groups: controls, passive smoking groups and passive smoking rats administered EPF at three dosage levels (75, 150 or 300 mg/kg/day) in drinking water for 4 months. A rat model of passive smoking was prepared by breeding male rats in a cigarette-smoking box. Bone mineral content (BMC), bone mineral density (BMD), bone turnover markers, bone histomorphometric parameters and biomechanical properties were examined.


RESULTS
Smoke exposure decreased BMC and BMD, increased bone turnover (inhibited bone formation and stimulated its resorption), affected bone histomorphometry (increased trabecular separation and osteoclast surface per bone surface; decreased trabecular bone volume, trabecular thickness, trabecular number, cortical thickness, bone formation rate and osteoblast surface per bone surface), and reduced mechanical properties. EPF supplementation during cigarette smoke exposure prevented smoke-induced changes in bone mineral status and bone turnover.


CONCLUSIONS
The results suggest that EPF can prevent the adverse effects of smoke exposure on bone by stimulating bone formation and inhibiting bone turnover and bone resorption.
Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha 410008, Hunan, China.
Shu-guang
SG
Gao
Ling
L
Cheng
Kang-hua
KH
Li
Wen-He
WH
Liu
Mai
M
Xu
Wei
W
Jiang
Li-Cheng
LC
Wei
Fang-jie
FJ
Zhang
Wen-feng
WF
Xiao
Yi-lin
YL
Xiong
Jian
J
Tian
Chao
C
Zeng
Jin-peng
JP
Sun
Qiang
Q
Xie
Guang-hua
GH
Lei
D015502:Absorptiometry, Photon; D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D001696:Biomechanical Phenomena; D015519:Bone Density / Q000187:drug effects*; D016723:Bone Remodeling / Q000187:drug effects*; D001862:Bone Resorption / Q000209:etiology / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control; D034181:Epimedium / Q000737:chemistry; D005269:Femur / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D047309:Flavones / Q000302:isolation & purification / Q000494:pharmacology*; D008159:Lumbar Vertebrae / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D008297:Male; D008855:Microscopy, Electron, Scanning; D009538:Nicotine / Q000097:blood; D010012:Osteogenesis / Q000187:drug effects; D010946:Plants, Medicinal; D051381:Rats; D017208:Rats, Wistar; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*
D015415:Biomarkers; D047309:Flavones; D014028:Tobacco Smoke Pollution; D009538:Nicotine