Search Results
You are looking at 1 - 4 of 4 items for
- Author or Editor: Ke Du x
- Refine by Access: All Content x
Abstract
The excessive prescription of antibiotics has led to an increasing number of antimicrobial resistances, posing a major public health concern. Therefore, the pharmacological research has shifted its focus to the identification of natural compounds that exhibit anti-pathogenic properties without triggering antibiotic resistance. Butyrate has received increasing attention as a promising candidate for the treatment of bacterial infections in the gastrointestinal tract, particularly when antibiotic treatment is contraindicated. This literature survey summarizes recently investigated antibacterial and immune-modulatory effects of butyrate. This survey revealed that butyrate exerts direct antimicrobial effects against distinct strains of Acinetobacter baumannii, Escherichia coli, Bacillus, and Staphylococcus species. In addition, in vitro and in vivo studies confirmed indirect antimicrobial effects of butyrate, which were exhibited via induction of host defensin production as well as by activation of innate and adaptive immune responses. Finally, the synergistic action of butyrate in combination with other antimicrobial compounds results in a striking clearance of bacterial pathogens. In conclusion, butyrate and its derivatives might be considered as promising antibacterial and immune-modulatory agents in order to tackle bacterial infections without antibiotics.
Abstract
As antimicrobial resistance poses a globally rising health problem, the identification of alternative antimicrobial agents is urgently required. The short chain fatty acid propionate which is physiologically produced by the gut microbiota constitutes a promising molecule given that it has been widely used as a cosmetics and food preservative due to its antimicrobial effects. This literature survey aims to determine the most recent state of knowledge about the antimicrobial and immune-modulatory properties of propionate. Both in vitro and in vivo studies published between 2011 and 2020 confirmed the ability of propionate to inhibit the growth of several cellular pathogens, including Gram-positive and Gram-negative multi-drug resistant bacteria and fungi. In addition, heterogenous immune-modulatory and in particular, anti-inflammatory effects of propionate could be assessed involving a diverse signaling network that needs further comprehension. In conclusion, our literature survey provides evidence that propionate displays a plethora of health-beneficial including antimicrobial and immune-modulatory effects. Future research is required to further unravel the underlying molecular mechanisms and to set the basis for in vivo infection and clinical studies to broaden the path of propionate as a promising adjunct antibiotics-independent option in the combat of infections caused by multi-drug resistant bacteria.
Abstract
Serious risks to human health are posed by acute campylobacteriosis, an enteritis syndrome caused by oral infection with the food-borne bacterial enteropathogen Campylobacter jejuni. Since the risk for developing post-infectious autoimmune complications is intertwined with the severity of enteritis, the search of disease-mitigating compounds is highly demanded. Given that benzoic acid is an organic acid with well-studied health-promoting including anti-inflammatory effects we tested in our present study whether the compound might be a therapeutic option to alleviate acute murine campylobacteriosis. Therefore, microbiota-depleted IL-10−/− mice were perorally infected with C. jejuni and received benzoic acid through the drinking water from day 2 until day 6 post-infection. The results revealed that benzoic acid treatment did not affect C. jejuni colonization in the gastrointestinal tract, but alleviated clinical signs of acute campylobacteriosis, particularly diarrheal and wasting symptoms. In addition, benzoic acid mitigated apoptotic cell responses in the colonic epithelia and led to reduced pro-inflammatory immune reactions in intestinal, extra-intestinal, and systemic compartments tested on day 6 post-infection. Hence, our preclinical placebo-controlled intervention trial revealed that benzoic acid constitutes a promising therapeutic option for treating acute campylobacteriosis in an antibiotic-independent fashion and in consequence, also for reducing the risk of post-infectious autoimmune diseases.
Abstract
Secondary abiotic (SAB) IL-10−/− mice constitute a valuable Campylobacter jejuni-induced enterocolitis model. Given that the host-specific gut microbiota plays a key role in susceptibility of the vertebrate host towards or resistance against enteropathogenic infection, we surveyed immunopathological sequelae of C. jejuni infection in human microbiota associated (hma) and SAB IL-10−/− mice. Following oral challenge, C. jejuni readily colonized the gastrointestinal tract of hma and SAB mice, but with lower numbers in the former versus the latter. Whereas hma mice were clinically less severely compromised, both, macroscopic and microscopic inflammatory sequelae of C. jejuni infection including histopathological and apoptotic cell responses in the colon of IL-10−/− mice were comparably pronounced in the presence and absence of a human gut microbiota at day 6 post-infection. Furthermore, C. jejuni infection of hma and SAB mice resulted in similarly enhanced immune cell responses in the colon and in differential pro-inflammatory mediator secretion in the intestinal tract, which also held true for extra-intestinal including systemic compartments. Notably, C. jeuni infection of hma mice was associated with distinct gut microbiota shifts. In conclusion, hma IL-10−/− mice represent a reliable C. jejuni-induced enterocolitis model to dissect the interactions of the enteropathogen, vertebrate host immunity and human gut microbiota.
