by In a recent publication in Molecular Psychiatry, researchers conducted a comprehensive review of existing literature to understand the impact of organ microbiomes on neuropsychiatric disorders. The study focused on uncovering the underlying mechanisms involved and identifying reliable biomarkers that could aid in the development of microbiota-targeted interventions for treating individuals with these disorders.
Neuropsychiatric disorders remain a significant global health concern, with no signs of reduction since 1990, according to the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD). Conditions such as bipolar disorder (BD), schizophrenia, major depressive disorder (MDD), autism spectrum disorder (ASD), substance use disorder, and anxiety disorders are prevalent worldwide and have a profound impact not only on patients but also on their families.
The prevalence of anxiety disorders and MDD has also risen due to the COVID-19 pandemic. Both genetic and environmental factors contribute to the development and manifestation of neuropsychiatric disorders. However, few studies have delved into the biological mechanisms associated with these disorders – making it crucial to gain a deeper understanding of the brain-body crosstalk and its influence on their pathogenesis.
The human body maintains homeostasis through a bidirectional network that encompasses brain-body crosstalk. This network involves various components such as neurotransmitters, the central nervous system (CNS), feedback loops, the peripheral nervous system, chemical signaling, hormones, and homeostasis itself.
Significant attention has been given to the role of the host microbiota in influencing overall health. The human body contains different types of microbiota, including those found in the mouth, nose, skin, gut, lungs, vagina, and bladder, each consisting of highly complex microbial communities.
The microbiota of one organ can have an impact on other organs. For instance, the gut microbiome has been shown to influence multiple organs and is closely linked to an individual’s overall health.
The gastrointestinal (GI) microbiota, which varies in diversity and composition across different parts of the digestive system, plays a crucial role in the bidirectional communication between the brain and gut. The gut microbiota-brain axis facilitates this communication and regulates brain functions and behavior through various mechanisms. For instance, gut microbes produce neurotransmitters and metabolites that can regulate brain activity.
Studies have revealed that patients with Alzheimer’s disease (AD) exhibit reduced levels of D-glutamate, a metabolite directly correlated with cognitive functions. As D-glutamate is also present in the peptidoglycan cell wall of bacteria, it suggests the potential for gut microbiota to produce this metabolite. Altered gut microbial composition and diversity have been associated with the manifestation of schizophrenia, anxiety, BD, MDD, Parkinson’s disease (PD), and AD. For example, a decrease in anti-inflammatory butyrate-producing bacteria and an increase in pro-inflammatory bacteria have been observed in various psychiatric disorders.
The oral cavity harbors a significant microbial community, which represents the second largest microbial population in the human body. Poor oral hygiene and a higher prevalence of dental decay have been observed in patients with psychiatric disorders. Periodontitis, an oral inflammatory condition, has been linked to the development of neuropsychiatric disorders.
Nasal microbiota, which consists of diverse microorganisms, also plays a role in the gut microbiota-brain axis through multiple pathways. Imbalances in nasal microbiota have been associated with various health conditions.
The lung microbiota, comprising different phyla, including Firmicutes, Bacteroidetes, and Proteobacteria, influences immune function, environmental exposure, host genetics, and lifestyle. While the role of the lung microbiota in the development and progression of neuropsychiatric disorders requires further exploration, its impact on systemic humoral factors has been established.
The skin, the largest organ in the human body, contains millions of microorganisms, protecting against pathogenic infestations. The microbial composition on the skin varies across different regions, and alterations in the skin microbiota have been linked to anorexia nervosa.
The composition and diversity of bladder and vaginal microbiota differ from that of the skin or gut microbiome. The vaginal microbiome, rich in Lactobacillus species, serves as a barrier against infection. However, studies have shown associations between vaginal microbiota, the prevalence of human papillomavirus (HPV), and conditions such as depression, eating disorders, premenstrual dysphoric disorder, and anxiety in women infected with HPV.
This comprehensive study highlights the importance of organ microbiomes in influencing neuropsychiatric disorders and provides insights into potential biomarkers and targeted interventions for their treatment. Further research in this field is needed to better understand the mechanisms involved and to develop effective strategies for managing and preventing these disorders.
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- Source: Coherent Market Insights, Public sources, Desk research
- We have leveraged AI tools to mine information and compile it
