|Die Pharmazie, 01 Mar 2017, 72(3):161-166. |
|3',4',7,8-Tetrahydroxyflavone inhibits RANKL-induced osteoclast formation and bone resorption.[Reference: WebLink]|
|Osteoclasts, which are specialized bone multinuclear cells, are responsible for bone lytic diseases such as osteoporosis. 3',4',7,8-Tetrahydroxyflavone is a flavonoid from Acacia confusa.
METHODS AND RESULTS:
In the present study, we found that 3',4',7,8-Tetrahydroxyflavone markedly inhibited receptor activator of nuclear factor kappa B ligand (RANKL)-induced osteoclastic differentiation from mouse bone marrow-derived macrophages (BMMs). 3',4',7,8-Tetrahydroxyflavone also reduced the mRNA expression levels of osteoclastic marker genes including the calcitonin receptor (CTR) and cathepsin K. In addition, 3',4',7,8-Tetrahydroxyflavone decreased the bone resorption activity of osteoclasts on dentin slices. We found that 3',4',7,8-Tetrahydroxyflavone inhibited RANKL-induced expression of c-Fos and nuclear factor of activated T cells c1 (NFATc1), a key transcription factor of osteoclast differentiation. Furthermore, ectopic overexpression of a constitutively active form of NFATc1 completely rescued the anti-osteoclastogenic effect of 3',4',7,8-Tetrahydroxyflavone, suggesting that the anti-osteoclastogenic effect was mainly attributed to the reduction in NFATc1 expression.
Taken together, our data suggest that 3',4',7,8-Tetrahydroxyflavone inhibits osteoclast differentiation and bone loss and may therefore be considered a promising drug candidate for treating or preventing bone-lytic diseases.
| Archives of Pharmacal Research, 2013, 36(6):723-730. |
|Antibacterial substances fromAlbizia myriophyllawood against cariogenicStreptococcus mutans.[Reference: WebLink]|
|Albizia myriophylla has been used for long by Thai traditional healers as an important ingredient herb in Thai herbal formulas for caries.
METHODS AND RESULTS:
In this study, three flavonoids lupinifolin (6), 8-methoxy-7,3',4'-trihydroxyflavone (7), and 7,8,3',4'-tetrahydroxyflavone (3',4',7,8-Tetrahydroxyflavone,8), a triterpenoid lupeol (3) as well as four sterols β-sitosterone (1), stigmasta-5,22-dien-3-one (2), β-sitosterol (4), and stigmasterol (5) were isolated from A. myriophylla wood. The antibacterial activity of these compounds against Streptococcus mutans ATCC 25175 was performed using broth microdilution method. All compounds exhibited antibacterial activity against S. mutans with minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) ranging from 1-256 and 2-256 μg/ml, respectively. Among the isolated compounds, lupinifolin (6) was found to be the most potent with MIC and MBC of 1 and 2 μg/ml, respectively. Lupinifolin (6) also showed a strong activity against ten clinical isolates of S. mutans with MIC and MBC ranging from 0.25-2 and 0.5-8 μg/ml, respectively.
These results reported the bioactive ingredients of A. myriophylla which support its ethnomedical claims as well. Lupinifolin (6) may have a potential to be a natural anticariogenic agent.