Objective:To demonstrate the effect of dieckol from Eisenia bicyclis on osteoclastogenesis using RAW 264.7 cells.Methods:Murine macrophage RAW 264.7 cells were subjected to dieckol treatment,followed by treatment with...Objective:To demonstrate the effect of dieckol from Eisenia bicyclis on osteoclastogenesis using RAW 264.7 cells.Methods:Murine macrophage RAW 264.7 cells were subjected to dieckol treatment,followed by treatment with receptor activator of nuclear factor kappa-B ligand(RANKL)to induce osteoclastogenesis.Tartrate-resistant acid phosphatase(TRAP)activity was examined using a TRAP activity kit.Western blotting analysis was conducted to examine the level of osteoclast-related factors,including TRAP and calcitonin receptor(CTR),transcriptional factors,including c-Fos,c-Jun,and nuclear factor of activated T cells cytoplasmic 1(NFATc1),nuclear factor kappa-B(NF-κB),extracellular signal-regulated kinase(ERK),and c-Jun N-terminal kinase(JNK).Immunofluorescence staining was conducted to examine the expression of c-Fos,c-Jun,and NFATc1.Results:Among the four phlorotannin compounds present in Eisenia bicyclis,dieckol significantly hindered osteoclast differentiation and expression of RANKL-induced TRAP and CTR.In addition,dieckol downregulated the expression levels of c-Fos,c-Jun,NFATc1,ERK,and JNK,and suppressed NF-κB signaling.Conclusions:Dieckol can suppress RANKL-induced osteoclastogenesis.Therefore,it has therapeutic potential in treating osteoclastogenesis-associated diseases.展开更多
The antioxidative properties of phlorotannins isolated from the brown alga Eisenia bicyclis were measured using the H-ORAC (Hydrophilic Oxygen Radical Absorbance Capacity) method. The ORAC values of phloroglucinol and...The antioxidative properties of phlorotannins isolated from the brown alga Eisenia bicyclis were measured using the H-ORAC (Hydrophilic Oxygen Radical Absorbance Capacity) method. The ORAC values of phloroglucinol and it’s oligomers: eckol, fucofuroeckol A, phlorofucofuroeckol A, dieckol, 8,8’-bieckol, were 2.57 ± 0.14, 4.97 ± 0.36, 9.82 ± 0.70, 8.97 ± 0.89, 10.22 ± 0.85, 8.62 ± 0.92 μmol Trolox equivalent/μmol, respectively. With the exception of eckol, the ORAC values of tested phlorotannins were higher than those of the well-known antioxidants (epigallocatechin gallate, resveratrol and L-ascorbic acid) used as positive controls. As a result of comparing with known ORAC values, it was found that the dieckol and fucofuroeckol A had stronger antioxidant activity than representative polyphenols (e.g., kaempferol, quercetin, myricetin and chlorogenic acid) derived from terrestrial plants.展开更多
基金supported by a National Research Foundation of Korea (NRF) grant funded by the Korea government (MSITNo. NRF-2020R1A2C1008527)
文摘Objective:To demonstrate the effect of dieckol from Eisenia bicyclis on osteoclastogenesis using RAW 264.7 cells.Methods:Murine macrophage RAW 264.7 cells were subjected to dieckol treatment,followed by treatment with receptor activator of nuclear factor kappa-B ligand(RANKL)to induce osteoclastogenesis.Tartrate-resistant acid phosphatase(TRAP)activity was examined using a TRAP activity kit.Western blotting analysis was conducted to examine the level of osteoclast-related factors,including TRAP and calcitonin receptor(CTR),transcriptional factors,including c-Fos,c-Jun,and nuclear factor of activated T cells cytoplasmic 1(NFATc1),nuclear factor kappa-B(NF-κB),extracellular signal-regulated kinase(ERK),and c-Jun N-terminal kinase(JNK).Immunofluorescence staining was conducted to examine the expression of c-Fos,c-Jun,and NFATc1.Results:Among the four phlorotannin compounds present in Eisenia bicyclis,dieckol significantly hindered osteoclast differentiation and expression of RANKL-induced TRAP and CTR.In addition,dieckol downregulated the expression levels of c-Fos,c-Jun,NFATc1,ERK,and JNK,and suppressed NF-κB signaling.Conclusions:Dieckol can suppress RANKL-induced osteoclastogenesis.Therefore,it has therapeutic potential in treating osteoclastogenesis-associated diseases.
文摘The antioxidative properties of phlorotannins isolated from the brown alga Eisenia bicyclis were measured using the H-ORAC (Hydrophilic Oxygen Radical Absorbance Capacity) method. The ORAC values of phloroglucinol and it’s oligomers: eckol, fucofuroeckol A, phlorofucofuroeckol A, dieckol, 8,8’-bieckol, were 2.57 ± 0.14, 4.97 ± 0.36, 9.82 ± 0.70, 8.97 ± 0.89, 10.22 ± 0.85, 8.62 ± 0.92 μmol Trolox equivalent/μmol, respectively. With the exception of eckol, the ORAC values of tested phlorotannins were higher than those of the well-known antioxidants (epigallocatechin gallate, resveratrol and L-ascorbic acid) used as positive controls. As a result of comparing with known ORAC values, it was found that the dieckol and fucofuroeckol A had stronger antioxidant activity than representative polyphenols (e.g., kaempferol, quercetin, myricetin and chlorogenic acid) derived from terrestrial plants.
