Immunomodulatory proanthocyanidins from Ecdysanthera utilis.
Two new A-type proanthocyanidins have been isolated from Ecdysanthera utilis and identified as epicatechin-(4beta-->8,2beta-->O-->7)-epicatechin-(4beta-->8)-epicatechin (5) and epicatechin-(4beta-->8)-epicatechin-(4beta-->8,2beta-->O-->7)-epicatechin-(4beta-->8)-epicatechin (6), respectively. The structure-related components epicatechin (1), procyanidin B2 (2), proanthocyanidin A1 (3), proanthocyanidin A2 (4), and aesculitannin C (7) were also isolated. All of these compounds were identified and evaluated for immunopharmacological activity. Human peripheral blood mononuclear cells (PBMC) were used as target cells, and cell proliferation was determined by (3)H-thymidine uptake. The results indicated that compound 3 suppressed PBMC proliferation activated with phytohemagglutinin (PHA). The inhibitory mechanisms may involve the blocking of interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) production, since compound 3 attenuated IL-2 and IFN-gamma production of PBMC in a dose-dependent manner. Therefore, it is suggested that immunomodulatory agents are present in E. utilis.
Lin
Lie-Chwen
LC
National Research Institute of Chinese Medicine, 155-1, Sec. 2, Li-Nung Street, Taipei (112), Taiwan, Republic of China. lclin@cma23.nricm.edu.tw
Kuo
Yuh-Chi
YC
Chou
Cheng-Jen
CJ
D000276:Adjuvants, Immunologic / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D000872:Anthocyanins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D029062:Apocynaceae / Q000737:chemistry*; D044946:Biflavonoids; D002392:Catechin / Q000031:analogs & derivatives / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism; D007376:Interleukin-2 / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000166:cytology / Q000187:drug effects*; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010835:Phytohemagglutinins / Q000494:pharmacology; D037121:Plant Lectins; D018547:Plant Stems / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D044945:Proanthocyanidins; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet; D013329:Structure-Activity Relationship; D013624:Taiwan
D000276:Adjuvants, Immunologic; D000872:Anthocyanins; D044946:Biflavonoids; D007376:Interleukin-2; D010835:Phytohemagglutinins; D037121:Plant Lectins; D044945:Proanthocyanidins; C457102:aesculitannin C; C457101:epicatechin-(4beta-8)-epicatechin-(4beta-8,2beta-O-7)-epicatechin-(4beta-8)-epicatechin; C457100:epicatechin-(4beta-8,2beta-O-7)-epicatechin-(4beta-8)-epicatechin; C013221:proanthocyanidin; C479580:procyanidin B2; C017674:procyanidin; D007371:Interferon-gamma; D002392:Catechin