Researchers from Duke and Emory universities have made a groundbreaking discovery about the sexually transmitted bacterium Neisseria gonorrhoeae, which causes gonorrhea. It appears that this bacterium is able to use sex hormones found in the human urogenital tract to resist antibiotic attacks and fight off antimicrobials.
Like many other bacteria, Neisseria gonorrhoeae possesses pumps that it uses to expel chemicals that could potentially kill it. However, what makes this bacterium unique is its ability to produce and use more of these pumps with the help of human sex hormones. This finding, published in Nature Communications, sheds light on how gonorrhea can become resistant to both intrinsic antimicrobials and prescribed antibiotics.
The researchers came across this mechanism while studying a transcription factor called MtrR, which regulates the production of efflux pumps in the bacterium. They found that MtrR has a particular affinity for binding to hormonal steroids such as progesterone, estrogen, testosterone, and the synthetic hormone ethinyl estradiol. However, when the transcription factor binds to these hormones, it becomes less effective at suppressing the production of bacterial pumps.
According to Duke graduate student Grace Hooks, the bacterium seems to be able to sense the hormonal environment of its host and colonize at the opportune time in the female menstrual cycle. In the week leading up to ovulation, estrogen levels rise dramatically, while progesterone peaks during the two weeks between ovulation and menstruation. These hormonal fluctuations are known to suppress the immune system, creating a window of vulnerability for gonorrhea to infect the urogenital tract.
The researchers suggest that Neisseria gonorrhoeae utilizes this sensory system to gauge the best timing for colonization. Hooks explains that the bacterium must be skilled at sensing its host’s hormonal cycle because it cannot survive outside of the human body. Understanding this mechanism could potentially lead to novel approaches in preventing or treating the infection.
In addition to its role in colonization, the transcription factor MtrR also helps the bacterium protect itself against reactive oxygen species. This dual function of the protein provides a robust defense for Neisseria gonorrhoeae.
While gonorrhea has a long history, dating back to ancient times, it continues to be a major public health concern. The Centers for Disease Control classifies gonorrhea as an urgent threat due to its resistance to antibiotics. Currently, the only effective antibiotic treatment is ceftriaxone, but strains resistant to this drug have been identified in Europe and Asia.
In women, untreated gonorrhea can lead to serious complications such as pelvic inflammatory disease and infertility. It can also be transmitted from mother to infant during childbirth. While the symptoms may be more apparent in men, they are equally susceptible to the infection due to the presence of the same sex hormones that the transcription factor binds to.
The researchers also discovered that the synthetic hormone ethinyl estradiol, commonly found in oral contraceptives, had a similar effect on the bacterium. This finding raises concerns about the potential for oral birth control to worsen gonorrhea infections.
Overall, this study provides valuable insights into the mechanisms that enable Neisseria gonorrhoeae to resist antibiotics and antimicrobials. Understanding how sex hormones play a role in this resistance could lead to new strategies for preventing and treating gonorrhea. Further research in this area is needed to develop targeted therapies that can effectively combat this ongoing public health threat.
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1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it
