A MECHANISM OF THE THEARUBIGIN FRACTION OF BLACK TEA (CAMELLIA SINENSIS) EXTRACT PROTECTING AGAINST THE EFFECT OF TETANUS TOXIN

• Published in: Journal of toxicological sciences Vol. 27; no. 5; pp. 441 - 447
• Main Authors: SATOH, Eiki, ISHII, Toshiaki, SHIMIZU, Yoshio, SAWAMURA, Shin-ichi, NISHIMURA, Masakazu
• Format: Journal Article
• Language: English
• Published: Japan The Japanese Society of Toxicology 01.01.2002; Japan Science and Technology Agency
• Subjects: Animals; Antioxidants - pharmacology; Black tea; Camellia sinensis; Catechin - analogs & derivatives; Catechin - pharmacology; Diaphragm - drug effects; Female; In Vitro Techniques; Male; Mice; Neuromuscular Blocking Agents - pharmacology; Paralysis - chemically induced; Paralysis - prevention & control; Phenols - pharmacology; Phrenic Nerve - drug effects; Phrenic-nerve diaphragm; Polyphenols; Specific binding; Synaptosomal membrane; Synaptosomes - drug effects; Tea - chemistry; Tetanus toxin; Tetanus Toxin - antagonists & inhibitors; Tetanus Toxin - toxicity; Thearubigin fraction
• ISSN: 0388-1350; 1880-3989
• DOI: 10.2131/jts.27.441

The aim of the present study was to elucidate the mechanism of the protective effect of black tea extract's thearubigin fraction against the action of tetanus toxin. The effects of thearubigin fraction extracted from a black tea infusion were examined for neuromuscular blocking action on tetanus toxin in mouse phrenic nerve-diaphragm preparations and on the binding of this toxin to the synaptosomal membrane preparations of rat cerebral cortices. The interaction between tetanus toxin and thearubigin fraction was also investigated. Tetanus toxin (4 μg/ml) abolished indirect twitches in mouse phrenic nerve-diaphragm preparations within 150 min. Thearubigin fraction mixed with tetanus toxin blocked the inhibitory effect of the toxin. Mixing iodinated toxin with thearubigin fraction inhibited the specific binding of [125I]tetanus toxin to the synaptosomal membrane preparation. The effects of thearubigin fraction were dose-dependent. The elution profile of [125I]tetanus toxin on Sephadex G-50 column chromatography was different from that of toxin mixed with thearubigin fraction. These findings indicate that thearubigin fraction protects against the action of tetanus toxin by binding with the toxin.