Effects of green tea fractions on oxygen-induced retinal neovascularization in the neonatal rat.

Abstract

This study aimed to investigate the preventive effects of green tea fractions (GTFs) on rat model of oxygen-induced retinopathy (OIR). Neonatal Sprague-Dawley rats were exposed to daily cycles of 80% oxygen (20.5 h), ambient air (0.5 h), and progressive return to 80% oxygen (3 h) until postnatal day 12 (P12), then the rats were placed in ambient air until P18. The green tea was fractionated by DM-A50, DM-W, M-B, and M-W. The rats were treated once daily from P6 to P17 by gastric gavage of GTFs (0.05 or 0.01 g/ml) or distilled water (DW) at 50 microl/10 g body weight. On P18, the rats were sacrificed and the retinal samples were collected. The retinal neovascularization (NV) was scored and avascular areas (AVAs) were measured as a % of total retinal area (%AVAs) in ADPase stained retinas. The NV scores in 0.01 g/ml M-W were significantly lower than those in DW. The %AVAs in 0.05 g/ml DM-A50 and in 0.05 g/ml and 0.01 g/ml M-W were significantly lower than those in DW. There were less catechins, and less caffeine in M-W fraction compared with other GTFs, suggesting components of green tea except for catechins and caffeine might suppress the neovascularization in rat model of OIR.

• Authors: Yuta Saito, Yasuko Hasebe-Takenaka, Toshihiko Ueda, Takako Nakanishi-Ueda, Shotaro Kosuge, Masaki Aburada, Tsutomu Shimada, Yukinobu Ikeya, Hidetoshi Onda, Hirotsugu Ogura, Yoko Taguchi, Hajime Yasuhara, Ryohei Koide
• Journal: Journal of clinical biochemistry and nutrition (J Clin Biochem Nutr) Vol. 41 Issue 1 Pg. 43-9 (Jul 2007) ISSN: 0912-0009 [Print] Japan
• PMID: 18392105 (Publication Type: Journal Article)