Research Advances in Protective Effects of Ursolic Acid and Oleanolic Acid Against Gastrointestinal Diseases

The intestinal tract plays an essential role in protecting tissues from the invasion of external harmful substances due to impaired barrier function. Furthermore, it participates in immunomodulation by intestinal microorganisms, which is important in health. When the intestinal tract is destroyed, it can lose its protective function, resulting in multiple systemic complications. In severe cases, it may lead to systemic inflammatory response syndrome (SIRS) and multiple organ dysfunction syndrome (MODS). Thus far, there are no curative therapies for intestinal mucosal barrier injury, other than a few drugs that can relieve symptoms. Thus, the development of novel curative agents for gastrointestinal diseases remains a challenge. Ursolic acid (UA) and its isomer, Oleanolic acid (OA), are pentacyclic triterpene acid compounds. Both their aglycone and glycoside forms have anti-oxidative, anti-inflammatory, anti-ulcer, antibacterial, antiviral, antihypertensive, anti-obesity, anticancer, antidiabetic, cardio protective, hepatoprotective, and anti-neurodegenerative properties in living organisms. In recent years, several studies have shown that UA and OA can reduce the risk of intestinal pathological injury, alleviate intestinal dysfunction, and restore intestinal barrier function. The present study evaluated the beneficial effects of UA and OA on intestinal damage and diseases, including inflammatory bowel disease (IBD) and colorectal cancer (CRC).