The Possible Effects of Different Hormones on Growth Rate and Ability of Biofilm Formation in Different Types of Microorganisms

In our study, it has been aimed to reveal the effects of estradiol, insulin, norepinephrine as a host factor on growth rate and biofilm formation of various microorganisms (uropathogenic Escherichia coli C7, Candida albicans SC5314, Enterococcus faecalis ATCC 29212, Methicillin resistant Staphylococcus auerus (MRSA) ATCC 43300 and Pseudomonas aeruginosa ATCC 27853). For this purpose, microorganisms were grown in different media (TSB and SDB) supplemented with/without various concentrations of hormones. Growth rates were measured in 4th, 6th and 24th hours period by a spectrophotometer. Statistical analysis of growth rates were determined by using two-way ANOVA Bonferroni post-test. Biofilm formations were evaluated via microtiter plate assay. The effects of hormones on biofilm formation were determined via one-way ANOVA Tukey's multiple-comparisons test. All hormone concentrations were shown to reduce the growth of E. faecalis statistically at 6 hours incubation. The growth of C. albicans was found to be altered (enhanced/reduced) only within the presence of high concentrations of different hormones. Besides there is no statistical significantly difference of any hormones tested on the growth rates of MRSA, P. aeruginosa and UPEC (p > 0.05). Similar to growth rate results, biofilm formations were shown to be altered with the presence all three hormones tested. However biofilm formations of P. aeruginosa and UPEC C7 were found to be not affected with the presence of any hormones tested (p > 0.05). It has been emphasized that, mammalian hormones determine the pathogenicity of infectious diseases as an environmental factor because they are known to affect microorganisms' behaviors as well. Our results have proven that, different concentrations of hormones have various effects on growth kinetics and virulence of microorganisms. All these studies showed that, hormones determine the infectious processes directly in human.