Prophylactic Effect and Antiulcerogenic Potential of Probiotic Lactiplantibacillus plantarum E1K2R2 and its Exopolysaccharide Against Ibuprofen-Induced Acute Gastric Ulcer.

Lactiplantibacillus plantarum (Lpb. plantarum), as a safe probiotic microorganism, has been documented for its production of multiple bioactive compounds, such as exopolysaccharides (EPS), which have been used in the treatment of many gastrointestinal diseases, including gastric ulcers. The present study aims to investigate the prophylactic and antiulcerogenic effects of the potential probiotic Lbp. plantarum E1K2R2 and its EPS against ibuprofen-induced gastric ulcer. A gastric ulcer model was established by feeding fasted rats with ibuprofen at a single dose (200 mg/kg body weight). The Lpb. plantarum E1K2R2 (10 CFU), its EPS (200 mg/kg bw), and the anti-ulcer reference drug (omeprazole) (20 mg/kg bw) were separately used to feed rats for seven consecutive days before ibuprofen administration. The mechanisms were meticulously examined, focusing on the anti-secretory activity and mucus production as well as the anti-inflammatory and antioxidant activities. The findings revealed that the gastro-preventive effect of Lbp. plantarum E1K2R2 (88.43%) was higher than that of the EPS (66.26%) and close to that of omeprazole (89.87%). This effect was achieved through similar mechanisms, including regulation of the secretory activity, augmentation of mucus production, mitigation of inflammation, and enhancement of the gastric mucosa's antioxidant capacity. Moreover, it was found that Lbp. plantarum E1K2R2 and its EPS induce the activities of gastric antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and S-transferase (GST); enhance glutathione (GSH) content; and reduce mucosal nitric oxide (NO), myeloperoxidase (MPO), and malondialdehyde (MDA) levels. Furthermore, histopathological and hematological examinations confirmed that both pre-treatments could effectively maintain the structural integrity of the gastric mucosa and improve some hematological parameters, respectively. This implies that Lpb. plantarum E1K2R2 and its EPS possess the potential to counteract ibuprofen-associated gastric ulcers, leveraging a variety of protective mechanisms.