Ellagitannin from Quercus infectoria eradicates intestinal colonization and prevents renal injuries in mice infected with Escherichia coli O157 : H7

Abstract

The use of antimicrobial agents in the management of patients infected with Shiga toxinproducing Escherichia coli (STEC) O157 : H7 remains controversial. Here, we examined the antibacterial efficacy of a natural product, ellagitannin from Quercus infectoria (Qi 4), against the organism in a murine model. Streptomycin-pretreated mice were orogastrically inoculated with 2¾10 9 c.f.u. streptomycin-resistant E. coli O157 : H7. The results demonstrated a stable high level of STEC present in the faeces of the infected animals. The bacterial levels in infected mice receiving Qi 4 at MIC and 2¾MIC were not significantly different from those of the untreated group (t-test; P.0.05). In contrast, Qi 4 at 4¾MIC significantly reduced the numbers of STEC within 2 days (t-test; 0.05.P.0.01). No viable bacteria were detected between day 5 and day 10. Similarly, at day 10, no organisms were detected from the intestines of the Qi 4-treated group, while they were recovered at levels of 10 8-11 and 10 5-10 c.f.u. g "1 in the colons and caeca of the infected mice, respectively. Histopathological findings from the infected kidneys revealed a marked increase in the number of mesangial cells and mesangial matrix. Ultrastructural examination of the kidneys from the infected mice also demonstrated proliferation of mesangial cells and an increase in the mesangial matrix. Cellular injury of endothelial cells with irregular borders and cytoplasmic bleb formation were noted. In contrast, the effects were not observed in the animals treated with Qi 4. The results clearly indicated that administration of Qi 4 could effectively eradicate the colonization of STEC O157 : H7 in the intestinal tract of mice and prevent renal injury. This compound may be an alternative candidate for a therapeutic agent against infections caused by this dangerous organism.

Scope of Hydrolysable Tannins as Possible Antimicrobial Agent

“…Treatment with 2× MIC did not reveal significant results, while with 4× MIC, the ETs were proved to be effective and the faeces showed to contain less STEC. The untreated groups showed endothelial cell injury, while the ET-treated groups showed no cell injury (Voravuthikunchai and Suwalak, 2012).…”

Understanding the Molecular Mechanisms of the Interplay Between Herbal Medicines and Gut Microbiota

“…However, the emergence of new pathogens and the increase of multiantibiotic‐resistant pathogens necessitate the development of ever new antimicrobials . In recent years, by in vitro test, various extracts of HMs worldwide have shown promising inhibitory effects on intestinal epithelial cell adherence, intracellular invasion, and enteric colonization of certain potential or opportunistic pathogens, typically E. coli , Helicobacter pylori , Campylobacter jejuni , Enterococcus faecalis , Salmonella typhimurium , Bacillus subtilis , Klebsiella pneumoniae , Shigella dysenteriae , Pseudomonas aeruginosa . Inhibition of potential or opportunistic pathogens in vivo by HMs was also observed in relevant disease models.…”

Treatment Strategies for Infections With Shiga Toxin-Producing Escherichia coli

“…Several studies have tested natural products for their ability to reduce or prevent Stx-induced cell or tissue damage in cell cultures in vitro or in animal infection models. An inhibition of cytotoxicity of Stx of E. coli O:157:H7 was found for white carob tree (Prosopsis alba) and Ziziphus mistol extracts (Pellarin et al, 2013) and for Ellagitannin from the Aleppo oak (Quercus infectoria) (Voravuthikunchai et al, 2012). Moreover, bacterial products such as lactic acid, linoleic acid, (Pittman et al, 2012), green tea extracts (Isogai et al, 1998(Isogai et al, , 2001, fruit juices (Nogueira et al, 2003), and other plant products (Takemasa et al, 2009;Lacombe et al, 2010;Lee and Stein, 2011;Sheng et al, 2016;Sewlikar and D'Souza, 2017;Patel et al, 2018) have been shown to have a beneficial effect on STEC-infected cells and animals alone or in combination of other agents, e.g., antibiotics.…”