To the Editor, I am writing to propose an interesting perspective on bacterial resistance: the Neuro-Microbial Interaction Hypothesis, which suggests that psychological states, including stress, anxiety, and positive cognition, may influence bacterial antibiotic resistance through neurotransmitter and hormonal signaling. Understanding this interaction could open new frontiers in microbiology and psychoneuroimmunology, offering potential strategies to mitigate bacterial resistance through psychological and neurochemical modulation. The human body and its microbiome are intricately linked through biochemical and neural pathways. Stress-related neurotransmitters and hormones such as cortisol, dopamine, and serotonin can modulate bacterial behavior, affecting growth, virulence, and possibly resistance mechanisms. Psychological stress triggers an increase in cortisol, which modulates immune function and gut microbiota composition, and cortisol has been shown to enhance biofilm formation, a key factor in bacterial resistance1. Likewise, epinephrine and norepinephrine can accelerate bacterial adaptation by activating stress-responsive genes associated with antibiotic survival2. Dopamine and serotonin, typically linked to mood regulation, have also been identified as microbial growth modulators, and their presence in the gut and bloodstream may influence bacterial gene expression, including genes involved in antibiotic resistance3. Some bacterial species even possess neurotransmitter receptors that allow them to sense and respond to host psychological states4. Moreover, chronic psychological stress may induce epigenetic modifications in bacterial genomes, potentially enhancing the activation of resistance-associated genes through changes mediated by histone-like proteins or small RNAs5. To explore this proposed interaction, I suggest investigating the neuro-microbial resistance link through several experimental approaches. One approach involves analyzing the microbiome in individuals with varying psychological stress levels by collecting and comparing microbiome samples from individuals experiencing high versus low stress and identifying differences in bacterial composition and resistance gene expression. Another approach is to evaluate the effects of neurotransmitters such as dopamine and serotonin, along with stress hormones such as cortisol and epinephrine, on bacterial growth, biofilm formation, and antibiotic susceptibility under controlled conditions, while employing RNA sequencing to assess neurochemical-induced gene expression changes. In addition, fluorescence microscopy can be used to track bacterial responses to host-derived neurochemicals in real time by visualizing bacterial behavior and measuring adaptation rates under different neurochemical exposures. If validated, this hypothesis could profoundly reshape our understanding of how psychological states influence infectious disease outcomes. Potential applications may include neuroimmune-based antibiotic strategies aimed at modulating neurotransmitter levels to enhance antibiotic effectiveness, the use of psychological therapy as an adjunct to antibiotic treatment by examining whether stress-reduction techniques such as meditation or cognitive therapy can indirectly reduce the development of resistance, and pharmacological targeting of microbial neuroreceptors to disrupt neurochemically mediated resistance pathways. The Neuro-Microbial Interaction Hypothesis thus emphasizes a psychological dimension in bacterial resistance, suggesting that mental states and neurochemical signals may critically influence microbial adaptation. Integrating microbiology, neuroscience, and psychology could unlock new therapeutic pathways to confront antibiotic resistance, making interdisciplinary research essential to further explore this intriguing connection. Author’s contribution The author is the sole contributor to the conception, design, and writing of this manuscript. The author is responsible for the scientific content and integrity of this study. Ethical statement Not applicable. Financial support and sponsorship Not applicable. Conflict of interests No conflict of interests declared.
Falah Hasan Obayes Al-Khikani (Thu,) studied this question.