Anti-invasive effects of curcuminoid compounds from Curcuma aromatica Salisb. on murine colon 26-L5 carcinoma cells

ショウガ科に属する Curcuma aromatica Salisb. の根茎のクロロホルム抽出エキスから,化学構造の明らかな4種のクルクミンおよびその関連化合物:curcumin(CA-1),demethoxycurcumin(CA-2),5\u27-methoxycurcumin(CA-3),bisdemethoxycurcumin(CA-4)を分離した。これらの化合物を用いてマウス結腸癌細胞(colon 26-L5)に対する増殖,基底膜への浸潤,細胞運動に及ぼす効果について検討した。クルクミン(CA-1)とその関連化合物(CA-2,3 および4)は,細胞に対して傷害性を示さない10μMの濃度において,マウス結腸癌細胞の基底膜への浸潤を抑制した(それぞれ22.8,28.9,10.3および62.0%の抑制率)。この癌細胞の運動能に対しても同様の抑制効果が観察された。これらのクルクミン関連化合物の中で,CA-4は強い抑制活性を持ち,癌細胞の浸潤および運動能に対して濃度依存的な抑制効果を示した。このように,クルクミン関連化合物の芳香族環のhydroxyl基およびmethoxyl基が癌細胞の浸潤活性の発現と関係している可能性が示唆された。 Bioassay-directed fractionation of the active chloroform extract from the rhizomes of Curcuma aromatica Salisb. (Zingiberaceae) led to the isolation of four main curcuminoid constituents: curcumin (CA-1), demethoxycurcumin (CA-2), 5\u27-methoxycurcumin (CA-3) and bisdemethoxycurcumin (CA-4). This is the first report to describe the isolation of CA-3 from C. aromatica. The chemical structures of these compounds were determined on the basis of spectral analysis and their inhibitory effects on the proliferation, invasion and migration of murine colon 26-L5 adenocarcinoma cells were evaluated in vitro. Curcumin and its analogues (CA-2, 3 and 4), at the non-cytotoxic concentration of 10μM, inhibited the invasive ability of colon 26-L5 cells to the ranges of 22.8, 28.9, 10.3 and 62.0%, respectively. A similar effect of these constituents on the migration of colon 26-L5 cells was also observed. Among these curcuminoids, CA-4 showed the strongest activities, inhibiting both tumor cell invasion and migration in a concentration-dependent manner

Two new bioactive iridoids from Rothmannia wittii

The first reported study of the isolation and identification of compounds from the bark and fruit of Rothmannia wittii yielded two new iridoids, 6β-hydroxy-10-O-acetylgenipin (1) and 10-O-acetylmacrophyllide (2) together with six known iridoids; 6β-hydroxygenipin (3), genipin (4), garjasmine (5), cerbinal (6), and mixture of β-gardiol (7) and α-gardiol (8); benzoic acid (9); vanillic acid (10); and stigmasterol (11). Their structures were elucidated by spectroscopic methods. Iridoid 1 showed antimycobacterial activity against Mycobacterium tuberculosis with a MIC value of 12.50 μg/mL. Iridoid 2 showed cytotoxicity against the NCI-H187 cancer cell line with an IC50 value of 6.82 μg/mL. In addition, 2 and 5 exhibited weak cytotoxic activity against KB and MCF-7 cell lines, while 4 was active against the NCI-H187 cancer cell line

Parviflorals A-F, trinorcadalenes and bis-trinorcadalenes from the roots of Decaschistia parviflora

Trinorcadalenes, parviflorals A and B (1 and 2), and four bis-trinorcadalenes, parviflorals C–F (3–6), together with the known trinorcadalenes, syriacusins A (7) and C (8), scopoletin (9) and stigmasterol were isolated from roots of Decaschistia parviflora. Their structures were established by spectroscopic techniques. The CD spectra of the bis-trinorcadalenes (3–6) established their absolute configurations at the binaphthyl axis. Further, structure 6 was confirmed by a single-crystal X-ray crystallographic analysis. Compounds 2 and 6 showed antimalarial activity against Plasmodium falciparum with IC50 values of 11.45 and 6.85 μM, respectively. Compounds 1, 5, 7 and 8 also exhibited weak antifungal activity against Candida albicans, with IC50 values in the range of 37.03–197.68 μM. Compounds 1–3 and 5–8 showed weak antimycobacterial activity against Mycobacterium tuberculosis with MIC values in the range of 54.30–192.13 μM. In addition, several of these compounds possessed cytotoxicity towards the cancer cell lines, KB, MCF7 and NCI-H187 with IC50 values in the range of 2.20–90.09 μM

Inhibition of two stages of melanin synthesis by sesamol, sesamin and sesamolin

Objective: To investigate the antimelanogenesis properties of three sesame compounds-sesamol, sesamin and sesamolin via two stages of melanin synthesis vis-à-vis sunscreen function and enzyme inhibition in melanoma cell line in order to search for alternative depigmenting agents. Methods: Antimelanogenic effects of sesame lignans were assessed in SK-MEL2 compared with the reference depigmenting agents, kojic acid and β-arbutin, in order to evaluate: (a) the sunscreen function of sesamol, sesamin and sesamolin by measurement of UV absorbtion property; (b) the inhibition of tyrosinase activity through mushroom and cellular tyrosinase; and (c) the effect on melanin content and melanogenic protein expression (tyrosinase, TRP-1 and TRP-2) by Western blot analysis; and (d) the toxicity of sesamol, sesamin and sesamolin to cells using cell cytotoxicity assay. Results: The results showed that sesamin, sesamolin and sesamol exerted satisfiable sunscreen function by absorbed UVB at 290 nm. Sesamol exhibited the highest inhibition of mushroom tyrosinase activity, but lipophilic sesamolin exhibited the highest cellular tyrosinase inhibition (IC50 of 1.6 μM) followed by sesamin, sesamol, and kojic acid, respectively. The order from high to low inhibition of melanin pigment was detected in the SK-MEL2 treated with sesamolin, sesamin, sesamol, kojic acid, and β-arbutin, respectively. Sesamolin and sesamin successfully inhibited cellular tyrosinase activity and respectively decreased TRP-1/TRP-2 (36%/15%) and TRP-1 levels (16%), thereby inhibiting melanogenesis via antityrosinase activity. No cytotoxicity to SK-MEL2 or Vero (normal) cell lines was observed at the lignan concentrations that exerted an antimelanogenic effect. Conclusions: Three sesame lignans prevent melanin synthesis through 2 stages: (a) by blocking melanin-induction and (b) by interrupting melanogenic enzyme production. This study provides evidence that sesamol, sesamin and sesamolin are potential for antimelanogenesis agents

Chemical constituents from the roots of <i>Leea thorelii</i> Gagnep.

<div><p>Phytochemical investigation of the roots of <i>Leea thorelii</i> led to the isolation of nine compounds. Their structures were determined from spectroscopic data as bergenin (<b>1</b>), 11-<i>O</i>-acetyl bergenin (<b>2</b>), 11-<i>O</i>-(4′-<i>O</i>-methylgalloyl) bergenin (<b>3</b>), 3,5-dihydroxy-4-methoxybenzoic acid (<b>4</b>), ( − )-epicatechin (<b>5</b>), 4″-<i>O</i>-methyl-( − )-epicatechin gallate (<b>6</b>), ( − )-epicatechin gallate (<b>7</b>), microminutinin (<b>8</b>) and stigmasterol. Compounds <b>1</b>–<b>8</b> are reported for the first time from this plant, and this is also the first report of the presence of <b>1</b>, <b>3</b>, <b>4</b>, <b>6</b> and <b>8</b> in the Vitaceae family.</p></div