Effect of Noradrenaline on the Virulence Properties ofCampylobacterSpecies

Abstract

Campylobacter species cause a spectrum of illnesses in humans. The type of illness and the outcome is dependent on the virulence of the infecting pathogen strain and host immune status. Acute stress can seriously compromise host immunity and increase susceptibility to infection. Noradrenaline (NA) is a stress hormone. Several studies have shown that it stimulated growth and increased the pathogenicity of organisms including E. coli and Campylobacter jejuni. However, the effect of NA on other Campylobacter species is unknown. We have examined the effect of NA on growth rate, motility, invasion of T84 epithelial cells, and colonisation of chickens by diverse Campylobacter species. Campylobacter cultures grown with NA had reduced lag phases, increased growth rates, and higher final optical densities than controls. The motility of Campylobacter was also significantly increased in the presence of noradrenaline. Some of the Campylobacter strains tested also showed increased invasion of T84 epithelial cells, greater breakdown of tight junctions, and an enhanced potential to colonise chickens. Our results show that noradrenaline-induced enhancement of virulence of Campylobacter can influence the outcome of infection.

An Investigation of the Effect of Catecholamines and Glucocorticoids on the Growth and Pathogenicity of Campylobacter jejuni

“…The presence of catecholamines resulted in a significant increase in growth for most isolates, and in the increased adhesion of Caco-2 cells for MF716, and in the increased invasion of Caco-2 cells for MF12581, SS72 and SS165, respectively. Similar results have been previously reported [15][16][17]. Increased growth was observed in response to epinephrine and norepinephrine, which has been widely reported [15][16][17].…”

“…Similar results have been previously reported [15][16][17]. Increased growth was observed in response to epinephrine and norepinephrine, which has been widely reported [15][16][17]. In contrast to Xu et al (2015), who observed increased growth in NCTC 11168 with the addition of epinephrine, the opposite effect was observed in our study.…”

“…Significantly increased motility in the presence of norepinephrine has also been previously reported [15,16], but was not observed in this study. This is possibly due to variations in assay conditions, as motility had been previously measured in basal media [16] and in iron-restricted nutrient-rich media [15], while, in this study, a semi-solid nutrient-rich agar was used.…”

“…Significantly increased motility in the presence of norepinephrine has also been previously reported [15,16], but was not observed in this study. This is possibly due to variations in assay conditions, as motility had been previously measured in basal media [16] and in iron-restricted nutrient-rich media [15], while, in this study, a semi-solid nutrient-rich agar was used. In the latter report, no difference in C. jejuni motility was observed, with the addition of norepinephrine in nutrient-rich media that was not iron-restricted, which is in agreement with the observations in this study [15].…”

“…Understanding the diverse manifestation of Campylobacter illness and its ability to persist in the harsh poultry environment and be rapidly transmitted to thousands of birds remains elusive, as it is a notoriously fastidious organism with limited virulence and survival factors compared to other pathogens. Associations between host stress and infection leading to more severe illness have been previously reported [15][16][17]. Indeed, it has been suggested that stress and a prior gastrointestinal infection are considered significant risk factors for the development of IBS, and stress may contribute to the development of septicemia, following bacterial infection [18,19].…”