Potential anthelmintics: polyphenols from the tea plant Camellia sinensis L. are lethally toxic to Caenorhabditis elegans

Abstract

A novel gallate of tannin, (-)-epigallocatechin-(2 beta-->O-->7',4 beta-->8')-epicatechin-3'-O-gallate (8), together with (-)-epicatechin-3-O-gallate (4), (-)-epigallocatechin (5), (-)-epigallocatechin-3-O-gallate (6), and (+)-gallocatechin-(4 alpha-->8')-epigallocatechin (7), were isolated from the tea plant Camellia sinensis (L.) O. Kuntze var. sinensis (cv., Yabukita). The structure of 8, including stereochemistry, was elucidated by spectroscopic methods and hydrolysis. The compounds, along with commercially available pyrogallol (1), (+)-catechin (2), and (-)-epicatechin (3), were examined for toxicity towards egg-bearing adults of Caenorhabditis elegans. The anthelmintic mebendazole (9) was used as a positive control. Neither 2 nor 3 were toxic but the other compounds were toxic in the descending order 8, 7 approximately 6, 9, 4, 5, 1. The LC(50) (96 h) values of 8 and 9 were evaluated as 49 and 334 micromol L(-1), respectively. These data show that many green tea polyphenols may be potential anthelmintics.

A Caenorhabditis elegans–based assay recognizes immunoglobulin light chains causing heart amyloidosis

“…This is essentially due to the reported peculiar specie-specific toxic effect of both EGCG and TETRA. 32,33 Overall, our work shows that C elegans can be considered a "biosensor" suitable for a rapid and inexpensive assessment of the cardiotoxic potential of LCs. Besides allowing the study of the molecular and functional consequences of exposure to LCs, we anticipate its possible use for screening LC cardiotoxicity in basic research and translational applications.…”

“…These findings are in agreement with the reported antihelminthic activity of chronic administration of TETRA and EGCG. 32,33 Discussion Although amyloid deposition is a defining feature of cardiac amyloidosis, the presence of fibrils is not sufficient to explain the cardiotoxicity observed in AL patients. 4,5 Clinically, the rapid improvement or worsening of cardiac function, which parallels variations in serum LC concentration in the absence of changes in amyloid load, Figure 4.…”

Pharmaceuticals and personal care products as emerging micropollutants in Brazilian surface waters: a preliminary snapshot on environmental contamination and risks

“…In some cases, PNECs were estimated in this work using assessment factors suggested by the European Commission 11 as well as toxicological data available elsewhere [20][21][22][23][24] . Table 1 shows a list of the most commonly investigated emergent micropollutants in Brazil and PNEC values obtained in the literature or estimated in the present work.…”

Structural Characteristics for Superoxide Anion Radical Scavenging and Productive Activities of Green Tea Polyphenols Including Proanthocyanidin Dimers

“…sinensis (cv., Yabukita), polyphenols 5-9 were isolated by essentially the same method as described previously. 7) An aliquot (160 ml) of the water-soluble portion, equivalent to 100 g dry material, was fractionated into fractions 1 (43.5 g), 2 (25.9 g), 3 (18.0 g), 4 (0.82 g), and 5 (10.2 g) by chromatography on a column (5ϫ95 cm) of Sephadex LH 20 (25-100 mm, Pharmacia Biotech) using EtOH, aqueous EtOH (90% and 80%), EtOH-acetone-water (2 : 2 : 1), and 70% aqueous acetone, respectively, as mobile phases. Fraction 3 (100 mg) was chromatographed on a column (2ϫ28 cm) of MCI GEL CHP 20P (75-150 mm, Mitsubishi Chemical) with water and aqueous EtOH (20% and 40%) as mobile phases.…”