title: Novel function of rare catechin, epigallocatechin-3-(3''-O-methyl)gallate, against cold injury in primary rat hepatocytes.
abstract: Epigallocatechin-3-(3''-O-methyl)gallate (EGCg-3''-OMe) is a rare component in green tea leaf and its bioactivity is hardly known. In this paper, we report that EGCg-3''-OMe has the function for cold preservation of primary rat hepatocytes. Confluent primary cultured hepatocytes were suspended in a storage solution, culture medium or cell banker (CB). EGCg-3''-OMe was tested as a supplement in the storage solution together with a general cryoprotectant, dimethylsulfoxide (DMSO). After 24 h cold preservation of cells at 4 degrees C followed by 1 h rewarming, cell viability and urea-synthesizing activity, one of the most important liver functions, were measured. EGCg-3''-OMe dose-dependently maintained cell viability and this effect was equal to that of a commercial CB at the highest concentration. Cell viability was also maintained after a further 24 h incubation at 37 degrees C of the cold-preserved hepatocytes. Conversely, urea-synthesizing activity was dose-dependently reduced by EGCg-3''-OMe. Cell protection by EGCg-3''-OMe due to the decrease in metabolic activity in cold-preserved cells was suggested. The decreased hepatic function of cells caused by EGCg-3''-OMe was rescued after a further 24 h incubation of cells at 37 degrees C.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamada-oka, Suita, Osaka 565-0871, Japan.
authors.forename: Noritaka
authors.initials: N
authors.lastname: Kagaya
authors.forename: Yukihiko
authors.initials: Y
authors.lastname: Hara
authors.forename: Ryoyasu
authors.initials: R
authors.lastname: Saijo
authors.forename: Akiko
authors.initials: A
authors.lastname: Kamiyoshi
authors.forename: Yoh-Ichi
authors.initials: Y
authors.lastname: Tagawa
authors.forename: Masaya
authors.initials: M
authors.lastname: Kawase
authors.forename: Kiyohito
authors.initials: K
authors.lastname: Yagi