Inhibitory effects of Camellia japonica on cell inflammation and acute rat reflux esophagitis

Abstract

Background: Oxidative stress and inflammation are the causes of many diseases. Reflux esophagitis (RE) is a common gastroesophageal reflux disease with a continuous upward trend in incidence worldwide. Camellia japonica (C. japonica) has long been used as a traditional herbal hemostatic medicine in China and Korea. The purpose of this study was to explore the anti-oxidant and anti-inflammatory activities of C. japonica and its protective effect against RE.Materials and methods: Buds from C. japonica plants were collected in a mountainous area of Jeju, South Korea. Dried C. japonica buds were extracted with 75% ethanol. DPPH and ABTS radical scavenging assays were performed. The ROS production and anti-inflammatory effects of C. japonica bud ethanol extract (CJE) on LPS-induced RAW264.7 cell inflammation were evaluated. The protective effects of CJE on RE were investigated in a RE rat model. Results: CJE eliminated over 50% of DPPH and ABTS radicals at concentrations of 100 and 200 μg/mL, respectively. CJE alleviated changes in cell morphology, reduced production of ROS, NO and IL-1β and down-regulated expression levels of iNOS, TNF-α, phosphorylated NF-κB, IκBα, and JNK/p38/MAPK. CJE reduced the esophageal tissue damage ratio (40.3%) and attenuation of histological changes. In addition, CJE down-regulated expression levels of TNF-α, IL-1β, and COX-2 and phosphorylation levels of NF-κB and IκBα in esophageal tissue. Conclusions: CJE possesses good anti-oxidation and anti-inflammatory activity, and can reduce RE damage in rats caused by gastric acid reflux. Therefore, CJE is a natural material that may be a candidate phytomedicine for the treatment of RE.