Showing papers by "Byung Sun Min published in 2019"
04 Apr 2019
TL;DR: Results suggest that arylbenzofurans from M. alba, especially mulberrofuran D2, are triple inhibitors of cholinesterase, BACE1, and GSK-3β and may represent a novel class of anti-AD drugs.
Abstract: Cholinesterase, β-site amyloid precursor protein cleaving enzyme 1 (BACE1), and glycogen synthase kinase-3β (GSK-3β) are the three main enzymes responsible for the early onset of Alzheimer’s disease (AD). The main aim of the present study was to delineate and accentuate the triple-inhibitory potential of arylbenzofurans from Morus alba against these enzymes. Overall, the enzyme inhibition assays demonstrated the prominence of mulberrofuran D2 as an inhibitor of AChE, BChE, BACE1, and GSK-3β enzymes with IC50 values of 4.61, 1.51, 0.73, and 6.36 μM, respectively. Enzyme kinetics revealed different modes of inhibition, and in silico modeling suggested that mulberrofuran D2 inhibited these enzymes with low binding energy through hydrophilic, hydrophobic, and π–cation interactions in the active site cavities. Similarly, in Aβ-aggregation assays, mulberrofuran D2 inhibited self-induced and AChE-induced Aβ aggregation in a concentration-dependent manner that was superior to reference drugs. These results sugges...
19 citations
TL;DR: The authors reported the isolation of five new diterpenoids from the bark of Cinnamomum cassia and elucidated their molecular structures by various spectroscopic methods including 1-and 2-dimensional NMR, high-resolution MS, and circular dichroism.
14 citations
TL;DR: 6,7,4′‐Trihydroxyflavone (THF), a compound from the heartwood of Dalbergia Odorifera inhibits receptor activator of NF‐κB ligand (RANKL)‐induced osteoclast differentiation, actin ring formation, and bone resorption in RAW 264.7 cells and bone marrow macrophage and prevented LPS‐induced bone loss in a mice model.
Abstract: The balance between the osteoblasts and the osteoclasts is important for the maintenance of the skeleton of the human body. The osteoclasts absorb bone after differentiated into polymorphonuclear cells by the fusion of monocytes/macrophages. We have found that 6,7,4'-Trihydroxyflavone (THF), a compound from the heartwood of Dalbergia Odorifera inhibits receptor activator of NF-κB ligand (RANKL)-induced osteoclast differentiation, actin ring formation, and bone resorption in RAW 264.7 cells and bone marrow macrophage. THF significantly inhibited the c-Jun-N-terminal kinase signaling pathway without affecting extracellular signal-regulated kinase, p38, and AKT signaling. Moreover, THF inhibited the expression of c-Fos, nuclear factor-activated T cells cytoplasm 1, cathepsin K, and c-src by RANKL. We used a lipopolysaccharide (LPS)-induced bone loss model in mice. Consequently, bone volume per tissue volume, trabecular number's reduction was recovered in THF-treated mice, and trabecular separation's augmentation was also attenuated by THF administration. In summary, THF inhibits RANKL-induced osteoclast differentiation by MAPK signaling pathway and inhibits bone resorption by destroying the actin ring in mature osteoclasts. THF also prevented LPS-induced bone loss in a mice model. Thus, THF may be useful in the treatment of bone diseases associated with excessive osteoclast differentiation and bone resorption.
14 citations
TL;DR: It is suggested that ECO and its major constituent, DMC, attenuated LPS-induced endotoxic shock by activating the Nrf2/HO-1 pathway.
14 citations
TL;DR: 2-arylbenzofuran analogs are supported as a promising class of PTP1B inhibitors and illustrates the key positions responsible for the inhibitory activity, their correlation, the effect of prenyl/geranyl groups, and the influence of resorcinol scaffold, which can be further explored in-depth to develop therapeutic agents against T2DM.
Abstract: Protein tyrosine phosphatase 1B (PTP1B) plays a specific role as a negative regulator of insulin signaling pathways and is a validated therapeutic target for Type 2 diabetes. Previously, arylbenzofurans were reported to have inhibitory activity against PTP1B. However, detailed investigation regarding their structure activity relationship (SAR) has not been elucidated. The main aim of this work was to investigate the PTP1B inhibitory activity of 2-arylbenzofuran analogs (sanggenofuran A (SA), mulberrofuran D2 (MD2), mulberrofuran D (MD), morusalfuran B (MB), mulberrofuran H (MH)) isolated from the root bark of Morus alba. All compounds demonstrated potent inhibitory activity with IC50 values ranging from 3.11 to 53.47 µM. Among the tested compounds, MD2 showed the strongest activity (IC50, 3.11 µM), followed by MD and MB, while SA and MH demonstrated the lowest activity. Lineweaver-Burk and Dixon plots were used for the determination of inhibition type whereas ligand and receptor interactions were investigated in modeled complexes via molecular docking. Our study clearly supports 2-arylbenzofuran analogs as a promising class of PTP1B inhibitors and illustrates the key positions responsible for the inhibitory activity, their correlation, the effect of prenyl/geranyl groups, and the influence of resorcinol scaffold, which can be further explored in-depth to develop therapeutic agents against T2DM.
13 citations
TL;DR: Three new sesquilignans, zijusesquillignans A-C (1-3), together with fifteen known compounds (4-18), were isolated from fruits of Ziziphus jujuba var.
13 citations
TL;DR: Findings suggested that these lignans exerted anti-inflammatory effects in RAW264.7 cells through modulation of the Nrf2/HO-1 pathway and that they were potential HO-1 inducers for preventing or treating inflammation.
Abstract: As part of our ongoing program to develop anti-inflammatory agents, an extract derived from Saururus chinensis collected in Korea was found to inhibit nitric oxide (NO) production in RAW264.7 cells. Bioassay-guided fractionation led to the isolation two new (1 and 2) and six known dineolignans (3–8). To the best of our knowledge, manassatin B1 (3) was isolated from S. chinensis for the first time. All structures were elucidated using extensive spectroscopic analysis. Of these compounds, 2 and 8 inhibited lipopolysaccharide (LPS)-induced production of NO and showed IC50 values of 5.80 and 1.52 µM, respectively. LPS-induced expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) was also significantly suppressed by the administration of 2 and 8. In addition, these lignans induced the expression of heme oxygenase-1 (HO-1) in a concentration-dependent manner. Nuclear translocation of nuclear-E2-related factor 2 (Nrf2), a key regulator of HO-1 protein expression, was also induced in RAW264.7 cells treated with 2 and 8. These findings suggested that these lignans exerted anti-inflammatory effects in RAW264.7 cells through modulation of the Nrf2/HO-1 pathway and that they were potential HO-1 inducers for preventing or treating inflammation.
11 citations
TL;DR: In this investigation of the chemical constituents of T. kirilowii roots, two previously undescribed sterols [trichosanhemiketal A and B (1 and 2)], together with 13 known compounds, were isolated and their structures were elucidated and the anti-inflammatory activity was determined.
9 citations
TL;DR: Results suggested that identification of the anti-osteoclastogenic compounds from C. operculatus flower buds may extend the understanding of molecular mechanisms underlying biological activities of the flower buds for osteoclast-related diseases.
8 citations
TL;DR: The combined results indicate that the anti-obesity and antidiabetic effect of PEF extract in mice fed an HFD may be caused by inhibition of lipid absorption as a result of reduced PL activity.
Abstract: Pleurotus eryngii var. ferulae (PEF) is traditionally used in the prevention and treatment of lifestyle-related diseases. In this study, we investigated the ability of PEF extract to prevent obesity and metabolic diseases and explored the underlying mechanism. Mice were fed a high-fat diet (HFD) containing PEF extract for 12 weeks, and their body weight, adipose tissue and liver weights, and lipid profiles and blood glucose levels, were monitored. Fecal triglyceride (TG) levels were also measured and olive oil-loading tests were performed. Furthermore, the effect of PEF extract on pancreatic lipase (PL) activity was examined in vitro. Treatment with PEF extract for 12 weeks resulted in a significant decrease in the HFD-induced increases in body weight, white adipose tissue weight, liver weights, and lipid profiles, and improved glucose tolerance and insulin sensitivity. To assess the mechanism underlying the effect of PEF extract on obesity and diabetes, we investigated its role in inhibiting lipid absorption. Consumption of an HFD containing PEF extract significantly increased the TG level in feces compared with the controls, suggesting inhibition of TG absorption in the digestive tract. Furthermore, PEF extract suppressed the increase in serum TG levels resulting from oral administration of a lipid emulsion to mice, confirming inhibition of TG absorption. Moreover, PEF extract inhibited PL activity in vitro. Our combined results indicate that the anti-obesity and antidiabetic effect of PEF extract in mice fed an HFD may be caused by inhibition of lipid absorption as a result of reduced PL activity.
7 citations
TL;DR: A simple, sensitive, and reliable analytical HPLC/PDA method was developed, validated, and applied to determine 10 marker compounds in Phlomis Radix as mentioned in this paper, and the isolates were evaluated for cytotoxic and anti-oxidant activities as well as DPPH-HPLC method.
Abstract: − The roots of Phlomis umbrosa (Turcz.) (Phlomidis Radix) have been traditionally used to treat cold, reduce swelling and staunch bleeding. Four iridoids (1 − 3 and 5) and six phenylethanoid derivatives (4, and 6 − 10) were isolated from the roots of P. umbrosa. A simple, sensitive, and reliable analytical HPLC/PDA method was developed, validated, and applied to determine 10 marker compounds in Phlomidis Radix. Furthermore, the isolates were evaluated for cytotoxic and anti-oxidant activities as well as DPPH-HPLC method. Among them, compounds 4 and 6 – 9 displayed potent anti-oxidant capacities using DPPH assay with IC50 values of 27.7 ± 2.4, 10.2 ± 1.1, 18.0 ± 0.8, 19.1 ± 0.3, and 19.9 ± 0.6 μM, and compounds 6, 8, and 9 displayed significant cytotoxic activity against HL-60 with IC50 values of 35.4 ± 3.1, 18.6 ± 2.0, and 42.9 ± 3.0 μM, respectively.
TL;DR: Nine compounds including one norisoprenoid, one polyol-glycoside, three sterols, and one sterols may serve as chemotaxonomic markers for Chlamydomonas sp.
TL;DR: The author would like to include conflict of interest statement of the online published article in order to clarify the statement made by the authors.
Abstract: The author would like to include conflict of interest statement of the online published article. The correct conflict of interest statement should read as: Conflict of interest The authors declare no conflict of interest.
TL;DR: In this article, the anti-inflammatory effects on RAW264.7 cells and the immunosuppressive effects by evaluating interleukin-2 (IL-2) production in Jurkat T cells using a MeOH extract of Panax notoginseng roots were examined.
Abstract: Here, we designed to examine the anti-inflammatory effects on RAW264.7 cells and the immunosuppressive effects by evaluating interleukin-2 (IL-2) production in Jurkat T cells using a MeOH extract of Panax notoginseng roots. The results showed that the MeOH extract inhibited the synthesis of nitric oxide (NO) in a dose-dependent manner (IC50 value of 7.08 μg/mL) and displayed effects on T cell activation at a concentration of 400 μg/mL. In efforts to identify the potent compounds, bioactivity-guided fractionation of the MeOH extract and chemical investigation of its active CH2Cl2-, EtOAc-, and butanol- soluble fractions led to the successful isolation and identification of eleven compounds, including two polyacetylenes (1, 2), a steroid saponin (3), seven dammarane-type ginsenosides (4 - 10), and an oleanane-type ginsenoside (11). Among them, compound 11 was isolated from this plant for the first time. Compound 2 exhibited potent inhibitory effects on NO synthesis and an immunosuppressive effect with IC50 values of 2.28 and 65.57 μM, respectively.
TL;DR: The author would like to include conflict of interest statement of the online published article in order to avoid confusion between the statement of interest and the actual article.
Abstract: The author would like to include conflict of interest statement of the online published article. The correct conflict of interest statement should read as.
TL;DR: Among them, compound 8 (litsenolide D2) exhibited the most potent cytotoxicity against the tested cell lines, including HeLa, HL-60, and MCF-7, with IC50 values of 17.6 ± 1.3, 4.2 ± 0.2, and 12.8 ±0.0 μM, respectively.
Abstract: From the pericarps of Litsea japonica (Thunb.) Jussieu, eighteen butanolide derivatives (1 - 18) were evaluated for their cytotoxic activity against HeLa, HL-60, and MCF-7 cells. Compounds 1 - 9 with 2-alkylidene- 3-hydroxy-4-methylbutanolides structure exhibited cytotoxic activities against cancer-cell lines. Among them, compound 8 (litsenolide D2) exhibited the most potent cytotoxicity against the tested cell lines, including HeLa, HL-60, and MCF-7, with IC50 values of 17.6 ± 1.3, 4.2 ± 0.2, and 12.8 ± 0.0 μM, respectively. Compound 8 induced apoptosis in a dose-dependent manner. Annexin V/Propidium Iodide (PI) double staining confirmed that 8 effectively induced apoptosis in MCF-7 cells. To the best of our knowledge, we have reported cytotoxic activity of butanolides from L. japonica against these cancer-cell lines for the first time.
TL;DR: The developed HPLC-PDA method easily, accurately, and sensitively quantified using eight marker compounds was applied to clarify samples between steam processed and unprocessed samples of C. chinensis by pattern analysis.
Abstract: Cuscuta chinensis Lam. and Cuscuta japonica Choisy are parasitic plants. C. chinensis seeds were traditionally used for treatment of kidney and liver deficiencies. C. japonica seeds were used as tonic medicine to improve liver function and strengthen kidneys, treatment of high blood pressure, chronic diarrhea, and sore eyes. Cuscutae Semen are seeds of only C. chinensis in Korean Herbal Pharmacopoeia (K.H.P.). The developed HPLC-PDA method easily, accurately, and sensitively quantified using eight marker compounds [hyperoside (1), astragalin, (2), quercetin (3), kaempferol (4), chlorogenic acid (5), 3,4-di-O-caffeoylquinic acid (6), 1,5-di-Ocaffeoylquinic acid (7), and 4,5-di-O-caffeoylquinic acid (8)]. In addition, the method may be used to distinguish seeds between C. chinensis Lam. and C. japonica Choisy. Furthermore, the result from the current study was applied to clarify samples between steam processed and unprocessed samples of C. chinensis by pattern analysis.