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Daofeng Chen - One of the best experts on this subject based on the ideXlab platform.

  • Anticomplement ent-labdane diterpenoids from the aerial parts of Andrographis paniculata.
    Fitoterapia, 2020
    Co-Authors: Wen Quan, Xin Jin, Daofeng Chen
    Abstract:

    Abstract Bioactivity-guided fractionation resulted in the isolation of two new ent-labdane diterpenoids (1–2), along with eighteen known congeners (3−20) from the aerial parts of Andrographis paniculata. Except andrographolide (3) and isoandrographolide (4), eighteen diterpenoids (1–2, 5–20) exhibited potent Anticomplement activity with the CH50 and AP50 values of 23.1–638.3 μg/mL and 54.2–603.9 μg/mL, respectively. The structure-activity relationships of the isolates showed that 14-dehydroxylation, glycosidation and the opening of lactone were essential for Anticomplement activity. Although inactive, andrographolide (3) was successfully transformed to Anticomplement compounds (5 and 10) in vitro by human fecal bacteria, indicating that this major ent-labdane diterpenoid of A. paniculata might also exhibit Anticomplement activity in vivo through their potential active metabolites. The targets of several bioactive ent-labdane diterpenoids in complement activation cascade were identified as well.

  • UPLC-MS identification and Anticomplement activity of the metabolites of Sophora tonkinensis flavonoids treated with human intestinal bacteria
    Journal of pharmaceutical and biomedical analysis, 2020
    Co-Authors: Xin Jin, Shaoxin Chen, Daofeng Chen
    Abstract:

    Abstract Anticomplement activity played an important role in anti-inflammatory effects of traditional Chinese herbs. The total flavonoids of Sophora tonkinensis (TFST) were inactive on the complement system but showed obvious Anticomplement activity after incubated with human intestinal bacteria in vitro. In order to discover the metabolic activation of TFST by intestinal flora, the constituents of TFST and its metabolites were identified by UPLC-ESI-LTQ/MS. Their Anticomplement activities were evaluated through the classical and alternative pathway. As a result, eighteen flavonoids were identified, including seven flavonoid glycosides, five aglycones and six isoprenylated flavonoids. All the glycosides (daidzein-4′-glucoside-rhamnoside, sophorabioside, rutin, isoquercitrin, quercitrin, ononin, trifolirhizin) were metabolized into their corresponding aglycones in different extent by human intestinal bacteria, resulting in the contents of the five aglycones were highly increased in 24 h. However, no changes have occurred on the six isoprenylated flavonoids. Interestingly, three aglycones (quercetin, formononetin and maackiain) had significantly more potent Anticomplement activities than their prototype glycosides. The results indicated that the enhancement of TFST Anticomplement activity was attributed to the active aglycones, especially formononetin and quercetin, produced by human intestinal bacteria. These aglycones are likely to be among the potential active components of S. tonkinensis for its inhibiting inflammation effects.

  • Juniperus pingii var. wilsonii acidic polysaccharide: Extraction, characterization and Anticomplement activity.
    Carbohydrate polymers, 2019
    Co-Authors: Long Xia, Deji, Mengxia Zhu, Daofeng Chen
    Abstract:

    Abstract A water-soluble acidic polysaccharide, XB-PS3, was isolated from the twigs of Juniperus pingii var. Wilsonii with a molecular weight of 86.04 kDa. By means of monosaccharide composition analysis, methylation, 2D NMR spectroscopy and UPLC-MS analysis, we concluded that XB-PS3 had a backbone composed of →2,4)-α-Manp-(1→ and →4)-α-GalpA-(1→ (60 % esterified), with an araban branch attached to O-2 of →2,4)-α-Manp-(1→. The possible repeating units were further validated by oligosaccharide analysis and partial acid hydrolysis. XB-PS3 exhibited potent Anticomplement activity with CH50 value of 117.23 ± 18.74 μg/mL and interacted with C3, C4, C5 and C9 in the complement activation cascade. However, the Anticomplement activity was significantly weakened when the galacturonic acids were reduced (CH50: 268.55 ± 16.82 μg/mL) or the branches were removed by partial hydrolysis (CH50: 197.76 ± 21.81 μg/mL), indicating the important role of uronic acids and branch structure in the polysaccharide’s Anticomplement activity.

  • Structural characterization and Anticomplement activities of three acidic homogeneous polysaccharides from Artemisia annua.
    Journal of ethnopharmacology, 2019
    Co-Authors: Jiang-yan Huo, Long Xia, Daofeng Chen
    Abstract:

    Abstract Ethnopharmacological relevance Artemisia annua L. is a heat-clearing Chinese medicine and well-known for its antimalarial constituent, artemisinin. It has gained increasing attention for its anti-inflammatory and immunoregulatory activities. Interestingly, the crude polysaccahrides of A. annua exhibited potent Anticomplement activity. This study was to isolate and characterize its Anticomplement homogeneous polysaccharides from A. annua, and reveal the relationship between structures and Anticomplement activities of the isolated polysaccharides. Materials and methods Water-soluble crude polysaccharides from the aerial parts of A. annua were extracted and fractionated by DEAE-cellulose and Sephacryl S-300 gel permeation chromatography. Homogeneity, molecular weight, monosaccharide composition, methylation and NMR analysis were performed to characterize the structures of homogeneous polysaccharides. Their Anticomplement activities and targeting components in the complement activation cascade were evaluated by hemolytic assays. Results Three homogeneous polysaccharides (AAP01-1, AAP01-2 and AAP01-3) were obtained from A. annua. AAP01-1 was composed of seven monosaccharides, including mannose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose and arabinose. AAP01-2 and AAP01-3 had similar monosaccharides with AAP01-1, except the absence of glucuronic acid. They were all branched acidic heteropolysaccharides with different contents of galacturonic acid (8%, 28% and 15% for AAP01-1, AAP01-2 and AAP01-3, respectively). AAP01-2 showed potent Anticomplement activity with CH50 value of 0.360 ± 0.020 mg/mL through the classical pathway and AP50 value of 0.547 ± 0.033 mg/mL through the alternative pathway. AAP01-3 exhibited slightly weaker activity (CH50: 1.120 ± 0.052 mg/mL, AP50: 1.283 ± 0.061 mg/mL), while AAP01-1 was inactive. Moreover, AAP01-2 acted on C1q, C3, C4, C5 and C9 components and AAP01-3 interacted with C3, C4 and C5 components in the activation cascade of complement system. Conclusion These results indicated that the relatively high contents of galacturonic acid were important for Anticomplement activities of the polysaccharides from A. annua. The Anticomplement polysaccharides are another kind of bioactive constituents conferring heat-clearing effects of A. annua.

  • Anticomplement compounds from Polygonum chinense
    Bioorganic & medicinal chemistry letters, 2018
    Co-Authors: Zheng Haochuan, Daofeng Chen
    Abstract:

    Abstract Five new compounds including two phenyldilactones (1, 2), two coumarins (3, 4) and a dimer of N-E-feruloyl tyramine (5) together with twenty-three known compounds (6–28) were isolated from a medicinal plant Polygonum chinense. The structures of the new compounds were established by detailed spectral analysis. The absolute configurations of 1 and 5 were elucidated by Mosher’s method, Mo2(OAc)4-induced electronic circular dichroism (ECD) data, and ECD calculation. All the compounds were found to show potent Anticomplement activity with CH50 and AP50 values ranging from 0.18 to 1.45 mM, and 0.26 to 2.80 mM, respectively. Phenyldilactones and phenylpropionic tyramines were firstly reported as Anticomplement agents. The targets of compounds 1, 3, 5 and 10 in complement activation cascade were identified as well.

Chantal Loirat - One of the best experts on this subject based on the ideXlab platform.

  • Anticomplement Treatment in Atypical and Typical Hemolytic Uremic Syndrome
    Seminars in Hematology, 2018
    Co-Authors: Fadi Fakhouri, Chantal Loirat
    Abstract:

    The dissection of the pathogenic mechanisms of the various forms of the hemolytic uremic syndrome (HUS) has paved the way for the design of specific efficacious treatments. Such mechanistic approach led to a revolution in the management of atypical HUS with the use of the first-in class C5 blocker, eculizumab. The availability of this Anticomplement drug has also raised unsettled questions regarding the cost or burden and optimal duration of therapy and its use in secondary HUS. The efficacy of eculizumab in Shiga toxin producing Escherichia coli-associated HUS is not to date established and the results of ongoing prospective studies are eagerly awaited. Nevertheless, the emergence of Anticomplement therapies (eculizumab and other drugs in development) has transformed our approach of HUS.

Hyeong-kyu Lee - One of the best experts on this subject based on the ideXlab platform.

  • Anticomplement activity of compounds isolated from the roots of Euphorbia kansui
    Journal of the Korean Society for Applied Biological Chemistry, 2011
    Co-Authors: Jung Hee Kim, Guanghai Shen, Joongku Lee, Hyeong-kyu Lee
    Abstract:

    The Anticomplement activity-guided fractionation of the methanol extract of Euphorbia kansui L. resulted in isolation of three diterpenes, two triterpenes, and two sterols (1–7) from ethyl acetate fraction. By spectroscopic analysis, their chemical structures were elucidated as: β-amyrin (1); kansuiphorin C (2); 3-O-(2′E,4′Z-decadienoyl)-ingenol (3); 3-O-(2,3-dimethylbutyryl)-13-O-n-dodecanoyl-13-hydroxyingenol (4); β-sitosterol (5); α-euphol (6); β-sitosterol-3-O-β-D-glucopyranoside (7). These compounds were investigated Pitin vitro for their Anticomplement activity against the classical pathway of the complement system, with compounds 2–4 exhibiting significant Anticomplement activity with respective 50% inhibitory concentration values of 44.1±3.8, 89.5±5.5, and 152.1±6.2 μM.

  • Xanthone constituents of the fruits of garcinia mangostana with Anticomplement activity
    Phytotherapy research : PTR, 2010
    Co-Authors: Gui-hua Quan, Jung Hee Kim, Hyeong-kyu Lee, A. Douglas Kinghorn, Young-won Chin
    Abstract:

    Phytochemical investigation of a chloroform-soluble fraction of the freeze-dried fruits of Garcinia mangostana (Clusiaceace) with Anticomplement activity in the classical pathway led to the identification of five known xanthones. The structures of these compounds were confirmed by interpretation of NMR and MS spectroscopic data. Of the isolates obtained, 1-isomangostin and garcinone E were found to be active constituents in the Anticomplement assay used.

  • Anticomplement activity of cycloartane glycosides from the rhizome of Cimicifuga foetida.
    Phytotherapy research : PTR, 2006
    Co-Authors: Ming-hua Qiu, Jung Hee Kim, Hyeong-kyu Lee, Byung-sun Min
    Abstract:

    A tetranor-cycloartane glycoside and two 9,19-cycloartane glycosides were isolated from the EtOAc-soluble fraction of the rhizome of Cimicifuga foetida. The structures of the compounds were determined to be cimilactone A (1), 25-O-acetylcimigenol 3-O-beta-D-xylopyranoside (2) and cimigenol 3-O-alpha-L-arabinopyranoside (3), respectively, using spectroscopic analysis. The three compounds were examined for their Anticomplement activity against the classical pathway of the complement system. Compound 1 showed significant Anticomplement activity with an IC50 value of 28.6 mu m, whereas compounds 2 and 3 were inactive. Copyright (c) 2006 John Wiley & Sons, Ltd.

  • Coumarins and chromones from Angelica genuflexa
    Natural product sciences, 2005
    Co-Authors: Bo-young Park, Jung Hee Kim, Byung-sun Min, Joongku Lee, Kyung Seop Ahn, Ok Kyoung Kwon, Hyeong-kyu Lee
    Abstract:

    Thirteen compounds were isolated from the roots of Angelica genuflexa through repeated silica gel column chromatography. Nine coumarins, isoimperatorin (1), osthol (2), demethylsuberosin (3), oxypeucedanin (4), heraclenin (5), pabulenol (7), umbelliferone (8), oxypeucedanin hydrate (9) and marmesinin (11), and four chromones, hamaudol (6), cimifugin (10), sec-O-glucosylhamaudol (12) and prim-O-glucosylcimifugin (13), were identified by physicochemical and spectroscopic analysis. Among these, compounds 3, 5, 6, 8, 12, and 13 were isolated for the first time from the roots of Angelica genuflexa. These coumarins and chromones were examined for their Anticomplement activity. Demethylsuberosin (3) showed a weak Anticomplement activity with an value of .

  • Isolation and Anticomplement activity of compounds from Dendropanax morbifera.
    Journal of Ethnopharmacology, 2003
    Co-Authors: Bo-young Park, Jung Hee Kim, Byung-sun Min, Tae-jin Kim, Donghee Kim, Kihwan Bae, Hyeong-kyu Lee
    Abstract:

    Abstract Dendropanax morbifera Leveille (Araliaceae) is used in Korea for a variety of disease, such as migraine headache and dysmenorrheal. A new polyacetylene (1) and six known compounds (2–7) were isolated from the leaves of this plant by conventional chromatographic techniques. The structure of the new polyacetylene (1) was determined as (9Z,16S)-16-hydroxy-9,17-octadecadiene-12,14-diynoic acid by spectroscopic means including 2D NMR, which comprised the determination of a chiral by modified Mosher’s ester method. Compounds 1–7 were investigated in vitro for their Anticomplement activity against the classical pathway of the complement system. Of these, compound 1 showed significant Anticomplement activity with 50% inhibitory concentration (IC50) value of 56.98 μM, whereas compounds 2–7 were inactive.

Byung-sun Min - One of the best experts on this subject based on the ideXlab platform.

  • Anticomplementary activity of oleanane-type triterpenes from the roots of Aceriphyllum rossii
    Archives of Pharmacal Research, 2012
    Co-Authors: Byung-sun Min
    Abstract:

    To gain a better understanding of the Anticomplement activity of triterpenoids, the complement activity of five unusual oleanane-type triterpenoids, bearing a carboxyl group at the C-29 position, were estimated against the classical pathway of a complementary system. The five triterpenoids were obtained from the roots of Aceriphyllum rossii (Saxifragaceae), and were determined to be aceriphyllic acids B–E ( 1–4 ) and K ( 5 ). Of the isolated compounds, compounds 1 , 2 and 5 showed Anticomplement activities, with IC_50 values of 328.4, 77.5 and 348.6 μM, respectively, whereas, compounds 3 and 4 were inactive. This showed that a carboxyl group at the C-23 position and an α-configuration of a hydroxyl group at the C-3 position in the olean-29-carboxylic acid triterpenoids seemed to play an important role in the Anticomplement activity of human serum against erythrocytes.

  • Anticomplementary activity of triterpenoids from the whole plant of Aceriphyllum rossii against the classical pathway
    Planta medica, 2008
    Co-Authors: Byung-sun Min, Jung Hee Kim, Ik-soo Lee, Min-jung Chang, Jae Kuk Yoo, Tran Manh Hung, Phuong Thien Thuong, Jong Pill Lee, Jin-cheol Kim
    Abstract:

    To provide a better understanding of the anti-complement activity of triterpenoids, seven unusual pentacyclic triterpenoids bearing a carboxyl group at C-27 were evaluated for their Anticomplement activities against the classical pathway of the complement system. The triterpenoids were isolated from the whole plant of Aceriphyllum rossii of the family Saxifragaceae and were determined to be 3alpha,23-isopropylidenedioxyolean-12-en-27-oic acid (1), 3-oxoolean-12-en-27-oic acid (2), 3alpha-hydroxyolean-12-en-27-oic acid (3), beta-peltoboykinolic acid (4), 3alpha,23-diacetoxyolean-12-en-27-oic acid (5), 23-hydroxy-3-oxoolean-12-en-27-oic acid (6) and aceriphyllic acid A ( 7). Among them, compounds 2, 3, and 5 showed significant Anticomplement activity on the classical pathway with IC (50) values of 71.4, 98.5, and 180.7 microM, respectively, whereas compounds 1, 4, 6, and 7 were inactive. Our findings suggest that both the ketone at C-3 and the methyl at C-23 in the oleanane triterpenoids with a carboxyl group at C-27 are important for the Anticomplement activity against the classical pathway.

  • Anticomplement activity of cycloartane glycosides from the rhizome of Cimicifuga foetida.
    Phytotherapy research : PTR, 2006
    Co-Authors: Ming-hua Qiu, Jung Hee Kim, Hyeong-kyu Lee, Byung-sun Min
    Abstract:

    A tetranor-cycloartane glycoside and two 9,19-cycloartane glycosides were isolated from the EtOAc-soluble fraction of the rhizome of Cimicifuga foetida. The structures of the compounds were determined to be cimilactone A (1), 25-O-acetylcimigenol 3-O-beta-D-xylopyranoside (2) and cimigenol 3-O-alpha-L-arabinopyranoside (3), respectively, using spectroscopic analysis. The three compounds were examined for their Anticomplement activity against the classical pathway of the complement system. Compound 1 showed significant Anticomplement activity with an IC50 value of 28.6 mu m, whereas compounds 2 and 3 were inactive. Copyright (c) 2006 John Wiley & Sons, Ltd.

  • Coumarins and chromones from Angelica genuflexa
    Natural product sciences, 2005
    Co-Authors: Bo-young Park, Jung Hee Kim, Byung-sun Min, Joongku Lee, Kyung Seop Ahn, Ok Kyoung Kwon, Hyeong-kyu Lee
    Abstract:

    Thirteen compounds were isolated from the roots of Angelica genuflexa through repeated silica gel column chromatography. Nine coumarins, isoimperatorin (1), osthol (2), demethylsuberosin (3), oxypeucedanin (4), heraclenin (5), pabulenol (7), umbelliferone (8), oxypeucedanin hydrate (9) and marmesinin (11), and four chromones, hamaudol (6), cimifugin (10), sec-O-glucosylhamaudol (12) and prim-O-glucosylcimifugin (13), were identified by physicochemical and spectroscopic analysis. Among these, compounds 3, 5, 6, 8, 12, and 13 were isolated for the first time from the roots of Angelica genuflexa. These coumarins and chromones were examined for their Anticomplement activity. Demethylsuberosin (3) showed a weak Anticomplement activity with an value of .

  • Isolation and Anticomplement activity of compounds from Dendropanax morbifera.
    Journal of Ethnopharmacology, 2003
    Co-Authors: Bo-young Park, Jung Hee Kim, Byung-sun Min, Tae-jin Kim, Donghee Kim, Kihwan Bae, Hyeong-kyu Lee
    Abstract:

    Abstract Dendropanax morbifera Leveille (Araliaceae) is used in Korea for a variety of disease, such as migraine headache and dysmenorrheal. A new polyacetylene (1) and six known compounds (2–7) were isolated from the leaves of this plant by conventional chromatographic techniques. The structure of the new polyacetylene (1) was determined as (9Z,16S)-16-hydroxy-9,17-octadecadiene-12,14-diynoic acid by spectroscopic means including 2D NMR, which comprised the determination of a chiral by modified Mosher’s ester method. Compounds 1–7 were investigated in vitro for their Anticomplement activity against the classical pathway of the complement system. Of these, compound 1 showed significant Anticomplement activity with 50% inhibitory concentration (IC50) value of 56.98 μM, whereas compounds 2–7 were inactive.

Hyung-in Moon - One of the best experts on this subject based on the ideXlab platform.