Inhibitory effects of (-)-loliolide on cellular senescence in human dermal fibroblasts.

Cellular senescence influences tumor suppression and progress, tissue repair and regeneration, tissue and organismal aging, and age-related diseases. Aging intervention might be an advantageous target for prevention and treatment of diverse age-related diseases. In this study, we investigated whether (-)-loliolide purified from the crude extract of Polygonum aviculare exerted inhibitory activity against cellular senescence in human dermal fibroblasts (HDFs). (-)-Loliolide diminished senescence-associated ß-galactosidase activity (SA-ß-gal), the level of p21 protein, and the level of reactive oxygen species in senescent cells induced by adriamycin treatment. (-)-Loliolide also attenuated SA-ß-gal activity in HDFs under replicative senescence. These findings imply that (-)-loliolide rescues cellular senescence in HDFs and might be useful for the development of dietary supplements or cosmetics that ameliorate tissue aging or age-associated diseases.

Quercetin-3-O-ß-D-glucuronide isolated from Polygonum aviculare inhibits cellular senescence in human primary cells.

Cellular senescence is known to contribute to tissue aging, a variety of age-related diseases, tissue regeneration, and cancer. Therefore, aging intervention might be useful for prevention of aging as well as age-related disease. In this study, we investigated compounds from Polygonum aviculare to determine if they inhibited cellular senescence in human primary cells, human dermal fibroblasts (HDFs) and human umbilical vein endothelial cells (HUVECs). Ten compounds from P. aviculare were purified and their inhibitory effects on adriamycin-induced cellular senescence were measured by observing senescence-associated ß-galactosidase (SA-ß-gal) activity and reactive oxygen species. Among them, compound 9 (quercetin-3-O-ß-D-glucuronide) showed inhibitory effects against cellular senescence in HDFs and HUVECs treated with adriamycin. Additionally, compound 9 rescued replicative senescence in HDFs and HUVECs. These data imply that compound 9 represses cellular senescence in human primary cells and might be useful for the development of dietary supplements or cosmetics that ameliorate tissue aging or aging-associated diseases.

Inhibitory effects of juglanin on cellular senescence in human dermal fibroblasts.

Cellular senescence contributes to tissue and organismal aging, tumor suppression and progress, tissue repair and regeneration, and age-related diseases. Thus, aging intervention might be a promising target for treatment and prevention of diverse age-related diseases. In the present study, we investigated whether juglanin purified from the crude extract of Polygonum aviculare exerted inhibitory activity against cellular senescence in human dermal fibroblasts (HDFs). Juglanin decreased senescence-associated ß-galactosidase activity (SA-ß-gal) and the level of reactive oxygen species in senescent cells induced by adriamycin treatment. Juglanin also repressed SA-ß-gal activity in HDFs under replicative senescence. These results suggest that juglanin represses cellular senescence in HDFs and might be useful for the development of dietary supplements or cosmetics that alleviate tissue aging or age-related diseases.

Inhibition of DNA topoisomerases I and II of compounds from Reynoutria japonica.

Three anthraquinones (1, 2 and 4), three stilbenes (5, 6 and 7) and 3,5-dihydroxybenzyl alcohol (3) were isolated from Reynoutria japonica. Their structures were identified as emodin (1), emodin-8-O-ß-D-glucoside (2), 3,5-dihydroxybenzyl alcohol (3), citreorosein (4), cis-resveratrol (5), trans-resveratrol (6) and trans-resveratrol-5-O-ß-D-glucopyranoside (7) by comparing their physicochemical and spectral data with published data. Compound 3 was isolated for the first time from the Polygonaceae family. Among the purified compounds, 3 showed more potent inhibitory activity against topoisomerase I (IC50: 4 µM) than camptothecin, as the positive control (IC50: 18 µM). Compounds 3, 4, 5, 6 and 7 showed stronger inhibitory activities toward DNA topoisomerase II (IC50: 0.54, 14, 15, 0.77 and 3 µM, respectively) than the positive control, etoposide (IC50: 44 µM). Compounds 1 and 4 displayed weak cytotoxicities against human lung cancer (A549), ovarian cancer (SK-OV-3), human liver hepatoblastoma (HepG2) and colon adenocarcinoma (HT-29) cell lines.

Manassantin A isolated from Saururus chinensis inhibits 5-lipoxygenase-dependent leukotriene C4 generation by blocking mitogen-activated protein kinase activation in mast cells.

In this study, manassantin A (Man A), an herbal medicine isolated from Saururus chinensis (S. chinensis), markedly inhibited 5-lipoxygenase (5-LO)-dependent leukotriene C(4) (LTC(4)) generation in bone marrow-derived mast cells (BMMCs) in a concentration-dependent manner. To investigate the molecular mechanisms underlying the inhibition of LTC(4) generation by Man A, we assessed the effects of Man A on phosphorylation of cytosolic phospholipase A(2) (cPLA(2)) and mitogen-activated protein kinases (MAPKs). Inhibition of LTC(4) generation by Man A was accompanied by a decrease in cPLA(2) phosphorylation, which occurred via the MAPKs including extracellular signal-regulated protein kinase-1/2 (ERK1/2) as well as p38 and c-Jun N-terminal kinase (JNK) pathways. Taken together, the present study suggests the Man A represents a potential therapeutic approach for the treatment of airway allergic-inflammatory diseases.

Inhibition of DNA topoisomerases I and II and cytotoxicity of compounds from Ulmus davidiana var. japonica.

Twenty five compounds including ten triterpenes (1-3, 5-11), six flavonoids (12-15, 24, 25), five lignans (17, 18, 21-23), two butenyl clohexnone glycosides (19-20), one fructofuranoside (16) and one fatty acid (4) were isolated from the roots of Ulmus davidiana var. japonica. The structures of those compounds were identified by comparing their physicochemical and spectral data with those of published in literatures. All the compounds were evaluated for DNA topoisomerase inhibitory activities and cytotoxicities. Among the purified compounds, 4 and 19 showed more potent inhibitory acitivities (IC(50): 39 and 19 µM, respectively) than camptothecin, as the positive control (IC(50): 46 µM) against topoisomerase I. Compounds, 4, 10, 12, 19, 24 and 25 showed strong inhibitory activities toward DNA topoisomerase II (IC(50): 0.1, 0.52, 0.47, 0.42, 0.17 µM and 17 nM, respectively), which were more potent than that of etoposide as positive control (IC(50): 20 µM). In A549 cell line, 5 and 6 showed cytotoxicities (IC(50): 4 µM and 3 µM, respectively, with IC(50) of camptothecin as positive control: 10.3 µM). In the HepG2 cell line, 3, 5 and 7 showed cytotoxicity (IC(50): 4, 3 and 4 µM, respectively, with IC(50) of camptothecin: 0.3 µM). Compounds 6, 12 and 23 showed cytotoxicities in the HT-29 cell line (IC(50): 19, 19 and 15 µM, respectively, with IC(50) of camptothecin: 2 µM).