Histopathological Restoration and Immunomodulatory Effects of Combined Plectranthus comosus and Allium sativum Extracts on Gastrointestinal Tissue in Salmonella typhi–Infected Wistar Rats
Keywords:
Salmonella typhi; Plectranthus comosus; Allium sativum; histopathology; gastrointestinal inflammationAbstract
Typhoid fever remains a major public health concern in endemic regions, with gastrointestinal inflammation and mucosal damage contributing significantly to disease severity and complications (Stanaway et al., 2021; Marchello et al., 2022). This study evaluated the in vivo therapeutic effectiveness of combined aqueous extracts of Plectranthus comosus and Allium sativum on intestinal histopathology and inflammatory responses in Salmonella typhi–infected rats. Male Wistar rats were orally infected with S. typhi and treated with combined plant extracts for 14 days at doses of 100, 150, and 200 mg/kg. Ciprofloxacin (10 mg/kg) served as a positive control. Histopathological assessment revealed severe villus atrophy, crypt hyperplasia, inflammatory infiltration, mucosal lesions, and necrosis in untreated infected rats. In contrast, extract-treated groups demonstrated dose-dependent restoration of intestinal architecture, with the 200 mg/kg dose producing near-normal villus height (470.0 ± 9.5 µm) and crypt depth (155.0 ± 5.2 µm), comparable to ciprofloxacin. Immunohistochemical analysis showed significant reductions in TNF-α and IL-6 staining intensities at the highest extract dose (TNF-α: 1.5 ± 0.1; IL-6: 1.6 ± 0.2), relative to untreated infected controls (TNF-α: 4.5 ± 0.2; IL-6: 4.8 ± 0.3). These findings were corroborated by qPCR analysis, which demonstrated marked downregulation of TNF-α and IL-6 mRNA expression. Overall, combined aqueous P. comosus and A. sativum extract therapy significantly attenuated intestinal inflammation and promoted mucosal recovery in S. typhi–infected rats, highlighting its potential as a complementary therapeutic strategy for typhoid-associated gastrointestinal pathology.
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