RESUMO
BACKGROUND: Aflatoxin (AF), a metabolite of Aspergillus flavus, is injurious to vital body organs. The bacterial defense against such mycotoxins has attracted significant attention. Lactic acid bacteria (LAB) are known to ameliorate AF toxicity. METHODS: Thirty adult male rats were divided into six groups (five each) to perform the experiments. The control (Co) group was fed a basal diet and water. Each of the following periods lasted 21 days: the milk (MK) group orally received milk (500 µL); LAB suspension (500 µL) containing 107 cfu/mL was orally provided to the LAB group; AF (0.5 mg/kg) was orally given to the AF group; and a combination of AF and LAB was administered to the AF + LAB group. The AF/LAB group was initially given AF for 21 days, followed by LAB for the same period. Finally, the rats were dissected to retrieve blood and tissue samples for hematological, biochemical, and histological studies. RESULTS: The results revealed a significant decrease in RBCs, lymphocytes, total proteins, eosinophil count, albumin, and uric acid, whereas the levels of WBCs, monocytes, neutrophils, creatinine, urea, aspartate aminotransferase, alkaline phosphatase, alanine aminotransferase, lactate dehydrogenase, and creatinine kinase significantly increased in the AF group in comparison to the control group. The histological examination of the AF group revealed necrosis and apoptosis of the kidney's glomeruli and renal tubules, nuclei vacuolization and apoptosis of hepatocytes, congestion of the liver's dilated portal vein, lymphoid depletion in the white pulp, localized hemorrhages, hemosiderin pigment deposition in the spleen, and vacuolization of seminiferous tubules with a complete loss of testis spermatogenic cells. Meanwhile, protective and therapeutic LAB administration in AF-treated rats improved the hematological, biochemical, and histological changes. CONCLUSIONS: The study revealed LAB-based amelioration to AFB1-induced disruptions of the kidney, liver, spleen, and testis by inhibiting tissue damage. The therapeutic effects of LAB were comparatively more pronounced than the protective effects.
RESUMO
To explore the prevalence of multidrug-resistant community-associated uropathogenic Escherichia coli (UPEC) and their virulence factors in Western Saudi Arabia. A total of 1,000 urine samples were examined for the presence of E. coli by selective plating on MacConkey, CLED, and sheep blood agar. Antimicrobial susceptibility patterns were determined using Vitek® 2 Compact (MIC) and the disc diffusion method with Mueller-Hinton agar. Genes encoding virulence factors (kpsMTII, traT, sat, csgA, vat, and iutA) were detected by PCR. The overall prevalence of UTI-associated E. coli was low, and a higher prevalence was detected in samples of female origin. Many of the isolates exhibited resistance to norfloxacin, and 60% of the isolates showed resistance to ampicillin. No resistance to imipenem, meropenem, or ertapenem was detected. In general, half of the isolates showed multiple resistance patterns. UPEC exhibited a weak ability to form biofilms, where no correlation was observed between multidrug resistance and biofilm-forming ability. All uropathogenic E. coli isolates carried the kpsMTII, iutA, traT, and csgA genes, whereas the low number of the isolates harbored the sat and vat genes. The diversity of virulence factors harbored by community-associated UPEC may render them more virulent and further explain the recurrence/relapse cases among community-associated UITs. To the best of our knowledge, this study constitutes the first exploration of virulence, biofilm-forming ability, and its association with multidrug resistance among UPEC isolates in Saudi Arabia. Further investigations are needed to elucidate the epidemiology of community-associated UPEC in Saudi Arabia.
