# Protective Effect of Ethanolic Extract of Djulis Hull on Indomethacin-Induced Gastric Injury
## 4 Discussion  
NSAIDs are effective in the treatment of inflammation, pain, fever, and clinical and rheumatoid arthritis, and are often used to treat these types of diseases [9]. One of the side effects caused by NSAIDs is gastric ulcer, such as destroying the normal gastric mucosal defense system, allowing gastric acid to cause damage to gastric mucosal cells and causing bleeding and ulcers [10; 32; 33]. As an NSAID, IND causes gastric ulcer via enhancing gastric acid secretion and triggers oxidative stress through the generation of free radicals [34; 35]. Administration of IND inhibits COX expression and reduces PG production, which are among the main causes of gastric mucosal damage [12; 13]. The claim of functional foods is to use foods as preventive supplements for diseases, and this study suggests that the benefits of diulis hull may lead to the development of a new antiulcer supplement. Certain previous reports have shown that diulis possesses several kinds of bioactive components, such as betanin, kaempfer, quercetin, and rutin, which can contribute to its biological activities [17; 21]. However, diulis hull, which is often discarded as a byproduct, is reported to have three times the betanin and twice the phenolic and flavonoid compounds of diulis seeds [22]. Betaine and flavonoids can inhibit the action of enzymes or transcription factors involved in the inflammatory response and are expected to reduce tissue damage [36; 37]. Betanin in diulis is also responsible for the source of red pigment and its associated antioxidant activity [38]. The phenolic components in diulis hull reveal reducing characteristics and act as antioxidants and antiinflammatory agents [39]. All these reasons suggest that diulis hull possesses the capacity to be exploited as a functional food for the prevention of gastric damage due to its active ingredients that can reduce gastric inflammation. In our preliminary study (\(n=3\) each group), we found that 120 mg/kg IND treatment caused appropriate gastric ulcer area in C57/BL mice, and preadministration of 200 mg/kg EEDH and 200 mg/kg water extract of diulis hull (WEDH) improved the gastric damage caused by IND. Among them, EEDH revealed better protective activity. That is why we chose 120 mg/kg IND, 200 and 500 mg/kg EEDH for subsequent experiment to elucidate whether a 2.5-fold higher dose of EEDH shows greater gastric gastroprotective effect. In  
Figure 5: Effects of EEDH pretreatment on the protein levels of TNF-\(\alpha\) (**A**) and iNOS (**B**) of gastric mucosa in mice administered with IND. Western blot was applied to determine the expression of TNF-\(\alpha\) and iNOS. Data are represented as means \(\pm\) SD (\(n=3\)). # \(p<0.05\) compared with control group. * \(p<0.05\), ** \(p<0.01\), and *** \(p<0.001\) compared with IND-treated group. this study, a single dose of IND treatment (120 mg/kg) was conducted to cause gastric damage in C57 BL/6] mice, and to investigate whether preadministration of different doses of EEDH (200 mg/kg and 500 mg/kg) for 21 days revealed gastoprotective ability. EEDH significantly reduced the ulcer area of gastric lesions induced by IND with a high ulcer protective index in a dose-response manner (Figure 1 and Table 1). Previous reports have shown that IND inhibits COX-1 expression, which leads to the decease of PG production and the occurrence of gastric mucosal injury [13; 40]. Moreover, apart from causing the gastric ulcer, the acute inflammatory response induced by IND also increases proinflammatory mediators such as TNF-\(\alpha\) and IL-6 [41]. IND-induced gastric injury was also associated with increased iNOS activity and malondialdehydehyde (MDA) production [42]. In addition, IND treatment reduced the levels of GSH and the activities of antioxidant enzymes (SOD and CAT) [43]. As antioxidants in the body system, CAT, SOD, and GSH scavenge free radicals and prevent gastric injury caused by oxidative stress.