Abstract
The bark and the leaf of Eucommia ulmoides Oliv. content similar bioactive components, but the leaf of this medically important plant is mostly abandoned. In this study, we revealed that the aqueous extract of E. ulmoides leaf (EUL) can promote the growth of the probiotic Lactobacillus bulgaricus (LB) and inhibit the formation of osteoclast in vitro. This extract was next administrated to senescence-accelerated mice P6 to evaluate examine its influence on the composition of gut microbiota (GM), short-chain fatty acids (SCFAs), and osteoporosis (OP). The results showed that supplementation of the EUL aqueous extract to the mouse model: (a) increased bacterial diversity and Firmicutes/Bacteroidetes ratio in the gut, (b) increased SCFAs concentration in the feces and serum, and (c) ameliorated OP based on the results of bone mineral density (BMD), Dual-energy X-ray bone scan, and HE staining of distal femur.