• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.2
• /
• pp.286-293
• /
• 2019

Alzheimer's disease (AD) is a neurodegenerative disease caused by accumulation of amyloid beta ($A{\beta}$) in the brain. In the present study, we investigated the neuroprotective effects of four flavonoids such as kaempferol, kaempferol-3-O-glucoside, quercetin, and quercetin-3-${\beta}$-D-glucoside against neuronal apoptosis induced by $A{\beta}$ in SH-SY5Y neuronal cells. Treatment with $A{\beta}$ decreased cell viability compared to the non-treated normal group. However, treatment with the four flavonoids increased cell viability in SH-SY5Y cells treated with $A{\beta}$. In addition, we measured the expression of apoptosis-related proteins such as Bcl-2-associated X protein (Bax) and cleaved caspase-9. Treatment with the four flavonoids down-regulated Bax and cleaved caspase-9 in $A{\beta}$-treated SH-SY5Y neuronal cells. Overall, the results of the present study demonstrated the neuroprotective effect of flavonoids by anti-apoptotic activity in $A{\beta}$-induced SH-SY5Y neuronal cells. These results suggest that these four flavonoids would be useful therapeutic and prevention agents for AD.

• Korean Journal of Plant Resources
• /
• v.10 no.1
• /
• pp.6-10
• /
• 1997

From the leaf of Prunus davidiana, naringenin and its glucoside, kaempferol and its glucoside, kaempferide glucoside, quercetin glucoside and d-catechin were isolated.

• Applied Biological Chemistry
• /
• v.41 no.2
• /
• pp.197-200
• /
• 1998

The MeOH extracts obtained from the flower petals of Carthamus tinctorius were solvent-fractionated with EtOAc, n-BuOH, and $H_2O$, successively. From the n-BuOH extract 2 flavonoid compounds were isolated through the repeated silica gel column chromatographies. From not only the results of physico-chemical data including HMBC but also the adaptation of acid hydrolysis, the chemical structures of the compounds were determined as $3-O-[{\beta}-D-glucopyranosyl(1{\rightarrow}2)\;{\beta}-D-glucopyranosyl]\;kaempferol$ and $3-O-[{\alpha}-L-rhamnopyranosyl(1{\rightarrow}6)\;{\beta}-D-glucopyranosyl]\;kaempferol$. The compounds exhibited $IC_{50}$ values in Grab2-Shc activity to be 43 and $47{\mu}g/ml$, respectively.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.25 no.3
• /
• pp.519-522
• /
• 1996

From the leaves of Lindera sericea Bl., kaempferol-3,7-0-di-a-L-rhamnopyranoside was isolated and characterized by spectral data and acid hydrolysis. This compound is reported for the first time from this plant. The content of kaempferol glycoside was high in May and June, and low in the fall. And the methoanolic extract of title plant showed the inhibitory effect on carrageenin-induced edema.

• Applied Biological Chemistry
• /
• v.43 no.4
• /
• pp.314-316
• /
• 2000

• YAKHAK HOEJI
• /
• v.33 no.2
• /
• pp.124-128
• /
• 1989

The drug consists of the dried entire plant of Viola diamantica (family Violaceae). It is used for the treatment of acute pyogenic diseases such as boil and carbuncles; also as tumor, high fever, tuberculosis and astringent hemostatic. Two flavonol glycosides have been isolated from the aerial parts of Viola diamantica and could be identifed as kaempferol 7-rhamnoside and kaempferol 3,7-dirhamnoside (bright yellow needle crystal, mp $225^{\circ}$, $C_{27}\;H_{30}\;O_4\;4H_2O$). Kaempferol 7-rhamnoside and kaempferol 3,7-dirhamnoside were first isolated from Viola diamantica.

• Korean Journal of Medicinal Crop Science
• /
• v.19 no.6
• /
• pp.426-434
• /
• 2011

In this study, to evaluate the anti-inflammatory effects of kaempferol and its rhamnosides isolated from Hibiscus cannabinus L. leaves, we investigated UVB-induced inhibitory effects on inflammatory reaction by measuring the cytokine as the prostaglandin ($PGE_2$), interleukine-6 (IL-6) and interleukine-8 (IL-8). We investigated the inhibitory effects of kaempferol and its rhamnosides on TARC (thymus and activation-regulated chemokine) and $PGE_2$. Kaempferol and ${\alpha}$-rhamnoisorobin showed inhibition activity of TARC generated to compared to positive control. Kaempferol, ${\alpha}$-rhamnoisorobin and afzelin Inhibited the release of $PGE_2$. Also, only kaempferol significantly inhibited interleukine-6 (IL-6), interleukine-8 (IL-8) among UVB-induced inflammatory cytokine.

• Korean Journal of Medicinal Crop Science
• /
• v.20 no.6
• /
• pp.454-460
• /
• 2012

In this study, kaempferol and its rhamnosides (${\alpha}$-rhamnoisorobin, afzelin, kaempferitrin) were isolated electively by bioconversion technology from Hibiscus cannabinus L. leaves to evaluate the anti-wrinkles effects and anti-microbial effects. In order to evaluate anti-wrinkles activity, reduction of expression matrix metalloproteinase-1 (MMP-1) protein and proliferation/ pro-collagen production were investigated. Kaempferol and ${\alpha}$-rhamnoisorobin showed inhibition activity of MMP-1 generated to compared to positive control. In HaCaT cell proliferation assay, kaempferol and ${\alpha}$-rhamnoisorobin significantly promoted cell proliferation in a concentration-dependent manner. In addition, procollagen synthesis assays (by HDF-N cell) showd that TGF-${\beta}$ induced procollagen production and also, all four kinds of experimental significantly promoted procollagen synthesis in a concentration-dependent manner. Kaempferol and ${\alpha}$-rhamnoisorobin exhibited strong antimicrobial activities on five of microbes, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Candida albicans and Aspergillus niger.

• Applied Biological Chemistry
• /
• v.48 no.1
• /
• pp.98-102
• /
• 2005

The MeOH extracts obtained from whole plant of Trigonotis peduncularis Benth. were solvent fractionated using EtOAc, n-BuOH and water, successively. The EtOAc and n-BuOH fractions gave four flavonol glycosides through application of silica gel and octadecyl silica gel (ODS) column chromatographies. The chemical structures of the flavonol glycosides were determined by the interpretation of several spectral data including 2D-NMR as $kaempferol-3-O-{\beta}-{D}-glucopyranoside\;(astragalin,\;1),\;kaempferol-3-O-{\alpha}-{L}-rhamnopyranosyl\;(1{\rightarrow}6)-{\beta}-{D}-glucopyranoside\;(nicotiflorin,\;2),\;quercetin-3-O-{\alpha}-{L}-rhamnopyranosyl(1{\rightarrow}6)-{\beta}-{D}-glucopyranoside\;(rutin,\;3),\;quercetin-3-O-{\beta}-{D}-glucopyranoside\;(isoquercitrin,\;4)$. The flavonoids have been first isolated from this plant. Nicotiflorin $(100\;{\mu}g/ml)$ showed $68.3{\pm}1.2%$ of the inhibitory effect on hACAT1(human Acyl CoA: cholesterol transferase 1) activity.

• Journal of Life Science
• /
• v.29 no.12
• /
• pp.1371-1377
• /
• 2019

Oxidative stress induced by the over-production of reactive oxygen species (ROS) in the brain is the most common cause of neurodegenerative diseases such as Alzheimer's. In the present study, we investigated the protective effects of flavonoids and their glycosides, namely kaempferol, kaempferol-3-O-glucoside, quercetin, and quercetin-3-β-D-glucoside, against H₂O₂-induced oxidative stress in the C6 glial cells. The H₂O₂-treated glial cells exhibited decreased cell viability and increased ROS production when compared with normal cells. However, cells treated with each of the four flavonoids/glycosides demonstrated significantly increased viability and suppressed ROS production when compared with the H₂O₂-treated control group. These results indicate that flavonoids/glycosides attenuate oxidative stress induced by H₂O₂ in C6 glial cells. To confirm the protective molecular mechanisms, we measured pro-inflammatory factors such as inducible nitric oxide synthase, cyclooxygenase-2, and interleukin-1β. H₂O₂ treatment was seen to elevate these factors and decrease IκB-α in the C6 glial cells, while the flavonoids/glycosides induced a down-regulation of the pro-inflammatory factors and increased IκB-α, indicating a neuroprotective effects through attenuation of the inflammation. In particular, quercetin and its glycoside showed a higher neuroprotective effect than the kaempferol treatments. These results suggest that these flavonoids and their glycosides could be promising therapeutic agents for neurodegenerative diseases via the attenuation of oxidative stress.