Effect of epimedium pubescen flavonoid on bone mineral status and bone turnover in male rats chronically exposed to cigarette smoke

Abstract

BackgroundEpimedii 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.MethodsFifty 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.ResultsSmoke 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.ConclusionThe 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.

Investigation of Chemical Composition, Antioxidant Activity, and the Effects of Alfalfa Flavonoids on Growth Performance

“…The O-phenolic group of flavonoids B ring poses as a hydrogen donor to receive free radicals and generated stable intramolecular hydrogen bonds with semiquinoid free radicals and thus blocking the free-radical chain reaction [37]. It has been reported that flavonoids can promote the proliferation and migration of adrenocortical stem cells and upregulate some growth hormones to improve animal growth and prevent the adverse effects of smoke exposure on bone by stimulating bone formation [38,39]. Noticeably, our results indicated that 70% EEFs represented dramatically DPPH free-radical-scavenging activity and could improve the growth performance and in vivo antioxidant of broilers, whereas the complex interplay between alfalfa flavonoids and in vivo antioxidant involved broilers fed with the different dose of 75% EEFs for 28 and 56 d needed to further analysis.…”

The Influence of Passive Tobacco Exposure and Physical Exercise on Bone Tissue of Young Rats

“…Gao et al 4 found similar results after 4 months of exposure to tobacco smoke. The literature shows that metabolic acidosis may negatively impact bone metabolism 2 .…”

“…Another fact that can be considered is that bone maturation only occurs after the 8th month of life in rats, 4 indicating a future possibility to investigate growth after the 8th month to assess the extent of the effect passive chronic smoking associated with swimming exercise has on a larger group of animals.…”

Three Months Aerobic Training Cannot Modulate C-Terminal Telopeptide of Type 1 Collagen in Cigarette Smokers

“…In this regard, it has been shown that nicotine affects the formation of bone due to the damage to the signaling pathways and metabolism associated with the extracellular matrix (24). It has also been reported that Gao et al (25) the exposure of male Wistar rats to cigarette smoke for 4 months, due to an increase in the levels of osteoclasts and decreased volume of bone connective tissue, the number and thickness of the connective tissue bands, the rate of bone formation, and the reconstruction of osteoblasts reduced the process of bone turnover. The increase in reactive oxygen species and free radicals due to smoking is also associated with the inhibition of the formation of osteoblasts in the bone surface (26).…”