Planta Med 2014; 80 - WS11
DOI: 10.1055/s-0034-1394552

The leaves of Diospyros kaki protect N-methyl-N-nitrosourea (MNU)-induced retinal degeneration in C57BL/6 mouse

SW Kang 1, KA Kim 1, HR Ahn 1, SH Jung 1
  • 1Functional Food Center, KIST Gangneung Institute, Gangwon, 210 – 340, Republic of Korea

Persimmon (Diospyros kaki Thunb.) leaves are used as a traditional folk medicine in Korea and considered to have various health benefits. We investigated the effect of ethanol extract of D. kaki (EEDK) on an animal model of retinal degeneration (RD), a leading cause of photoreceptor cell death resulting in blindness. In a RD mice model, in which retinal damage was indued by intraperitoneal injection of N-methyl-N-nitrosourea (MNU) (50 mg/kg), a DNA-methylating agent that causes photoreceptor damage. Various concentrations of EEDK were daily administered, orally, for 1, 2, and 4 weeks after MNU injection. EEDK markedly reduced up-regulation of glial fibrillary acidic protein (GFAP) and inhibited up-regulation of cleaved caspase-8. Moreover EEDK up-regulated rhodopsin against RD. Morphologically, the outer nuclear layer, where photoreceptors reside, was well preserved in the EEDK-treated mice retinas throughout the experimental period. To standardize EEDK, we performed chromatographic analysis and identified 8 flavonoids as marker compounds using spectroscopic methods. These results demonstrate that EEDK has protective effects against MNU-induced retinal damage, and may be considered as an agent for treating or preventing retinal degeneration.

Keywords: Diospyros kaki, MNU, N-methyl-N-nitrosourea, retinal degeneration