-Terpineol Mitigates Dextran Sulfate Sodium-Induced Colitis in Rats by Attenuating Inflammation and Apoptosis

Ulcerative colitis(UC) is one of the major inflammatorydisordersof the gastrointestinal tract. & alpha;-Terpineol (& alpha;TL) is naturallypresent in several plants, and it belongs to the monoterpenes category.& alpha;TL possesses various pharmacological properties such as antioxidant,antibacterial, antifungal, anticancer, and antiulcer activities. Importantly,& alpha;TL has been reported to possess potent anti-inflammatory effectsalso. In this study, we hypothesize that & alpha;TL may have protectiveeffects against dextran sodium sulfate (DSS)-induced colitis in Wistarrats. Animals were randomly allocated to 3 groups of 6 rats each.In group III, & alpha;TL was administered at a dose of 50 mg/kg b.wt. orally from days 1 to 14, while in groups II and III, 4% DSS indrinking water was given to rats ad libitum from the 7th to 14th days.After 24 h of the last dose of & alpha;TL, all animals were euthanized.& alpha;TL administration reduced the DSS-induced colonic disease activityindex, tissue damage, and goblet cell disintegration. & alpha;TL suppressedthe orchestration of mast cells in the inflamed colon, enhanced theimmunostaining of NF-kB-p65, COX-2, iNOS, p53, caspase-9, and cleavedcaspase-3, and suppressed the immunostaining of connexin-43, survivin,and Bcl-2. The activities of caspases-9 and -3 were reduced significantlyby & alpha;TL pretreatment, as also confirmed by calorimetric assays.Moreover, & alpha;TL significantly attenuated the nitric oxide leveland myeloperoxidase activity. Histological results further supportthe fact that & alpha;TL reduced DSS-induced colonic damage and reducedinflammatory cell infiltration. Overall, our findings suggest that & alpha;TL has strong protective effects against DSS-induced colitisby mitigating inflammatory and apoptotic responses.