Extract of Moutan radicis cortex and Cinnamomi ramulus ameliorates laser-induced choroidal neovascularization in Brown-Norway rats

Background: Moutan radicis cortex (MRC) and Cinnamomi ramulus (CR) are commonly used in eastern Asian traditional medicine to treat various diseases including cerebrovascular and cardiovascular, and have wide spectrum of pharmacological activities. However, the effect against laser-induced choroidal neovascularization (CNV) of extract of MRC and CR (1:1) (MRCCR) has not yet been studied. Purpose: Our aim was to investigate the inhibitory effect of MRCCR on pathological CNV in laser-treated Brown Norway (BN) rats. Methods: MRCCR (60, 90 mg/kg) was orally administered twice per day for 15 days from the day of CNV formation in laser-treated BN rats. Effects of MRCCR or its constituents on cell migration, tube formation, hyper permeability and phosphorylation of FAK/p38 MAPK were confirmed in humane retinal microvascular endothelial cells or human retinal pigment epithelial cells. Results: MRCCR significantly reduced the CNV lesions areas and the extent of fluorescein leakage. MRCCR and its constituents such as ellagic acid, paeonol or gallic acid decreased cell migration, tube formation or hyper permeability. MRCCR inhibited the phosphorylation of FAK and p38 MAPK. Conclusion: Combining the oral MRCCR and intravitreal injection of anti-VEGF medicine may result in a more potent therapeutic effect and consequently bring the reduction in eye injection numbers for patients with wet AMD.

Automated summary

The combined extract of Moutan radicis cortex and Cinnamomi ramulus showed inhibitory effect against laser-induced pathological CNV by reducing lesion areas and fluorescein leakage. The extract and its constituents also decreased cell migration, tube formation, and hyper permeability while inhibiting phosphorylation of FAK and p38 MAPK, suggesting potential therapeutic strategies for wet AMD patients.