Gut health improvement by locally isolated probiotics and histomorphometric analysis in Wistar rats

• Lab-isolated bacterial strains have been identified as probiotics. • Isolated probiotics improved the rats’ guts’ morphology. • Probiotics have no observed adverse effects on rats’ guts’ morphology. In the present investigation, lab-isolated probiotics Weisella confusa MZ735961.1, Lactiplantibacillus plantarum MZ707748.1 , L. plantarum MZ710117.1 , and L. plantarum MZ735961 were used separately and in combinations to evaluate their effect on gut morphology of Wistar rats. Synergistic groups were formed by 1:1 and labeled as G1 ( L. plantarum MZ707748.1 and L. plantarum MZ729681.1), G2 ( W. confusa MZ735961.1 and L. plantarum MZ727611.1), G3 ( L. plantarum MZ729681.1, W. confusa MZ735961.1, and Lactobacillus acidophilus La-14), G4 (all above mentioned probiotics). Rats were gavage-fed with probiotics according to their colony-forming unit (CFU). The experiment was carried out for 35 days. The bacteria were re-isolated from the gut and identified by biochemical tests which confirmed the administration and re-isolation of different Lactobacillus strains from the gut. Molecular characterization was done through 16S rRNA by using universal primers. After sequencing eight Lactobacillus strains were identified. Histopathology of rats’ intestines was done, and different parameters were examined. Villus height, crypt height, crypt width, mucosa, and sub-mucosa of jejunum were significantly (p = 0.00) increased in the G3 synergetic probiotic group compared to 0-day and negative control. However, the villus width showed non-significant (p > 0.05) variations in both genders. Mucosa tunic, muscle tunic, total wall, and crypt depth were significantly increased (p = 0.00) in the G4 group of medial colon. The study concluded that gut morphology improves as probiotics adhere better to the intestinal epithelium, excluding pathogens, reducing inflammation, enhancing nutrient absorption, and stimulating mucosal growth. This results in improved villus structure and gut wall integrity.