Aspirin effect on virulence of Candida albicans in stroke sufferers

Abstract

Oral carriage rate of Candida albicans in stroke sufferers on aspirin was found to be lower than their non-aspirin counterpart. Although aspirin has a direct inhibitory effect on Candida albicans, the exact mechanism leading to a lower carriage rate is still unknown. Objectives: 1) To determine the adhesion of Candida albicans to buccal epithelial cells and the phospholipase, proteinase and haemolytic activities in stroke sufferers, and 2) To investigate the correlations between these virulence factors. Methods: Nineteen C. albicans isolates were obtained from stroke sufferers on aspirin. Four reference strains isolated from non-stroke sufferers served as control. The isolates were tested for in vitro phospholipase, proteinase and haemolytic activities using three different plate assays. Adhesion to buccal epithelial cells was determined by an established adhesion assay. Results: No significant different in phospholipase activities was found between the test group and the control. Higher proteinase and haemolytic activities were found in the test group (P < 0.001) and adhesion was higher in the control (P <0.001). Adhesion was correlated with proteinase and haemolytic activities (P < 0.001). Conclusions: These data provide evidence of altered extracellular enzyme activities in Candida isolates taken from stroke sufferers on aspirin. The higher proteinase and haemolytic activities in the aspirin group could be a compensatory mechanism for the attenuated Candida in order to maintain its virulence in the host environment.