The human gut is inhabited by a plethora of micro-organisms, collectively called the “microbiota,” which are important for normal physiological processes. “Dysbiosis” or an imbalance in their populations can, however, contribute to the pathology of gastrointestinal diseases such as inflammatory bowel disease (IBD).
IBD, a disease highly prone to relapse, is known to be an outcome of genetic factors, dietary influences, and host-microbe interactions, and has caught the attention of researchers worldwide; considerable efforts now being directed towards understanding the role of dysbiosis in the pathogenesis of IBD. However, there remain several gaps in our understanding of this complex condition.
Researchers from the Peking Union Medical College, China and the Chinese Academy of Medical Sciences have delved deeper into understanding multi-dimensional dysbiosis and technologies that can aid the diagnosis and treatment of IBD. “Over the past decade, our knowledge on the microenvironment has boomed, with the development of next-generation sequencing, enabling a closer look at the dynamics of microbial interactions and functional alternations,” says Professor Jing-Nan Li, corresponding author of their review article, published in the Chinese Medical Journal on 5th April 2020.
The researchers first discuss the differences in gut microbiota in patients with IBD and healthy individuals, and how these changes can trigger imbalances in important metabolites such as short chain fatty-acids, required for normal physiological processes. Next, they describe the “mycobiome” or fungal microbiota, that has been relatively less explored, and their interplay with bacterial populations. They further shed light on the interaction of intestinal fungi with host immune responses and metabolic pathways, and how these interactions help maintain gut “homeostasis” (balance).
The researchers also elaborate on advanced technologies that enable a holistic understanding of complex diseases like IBD. A “multi-omics” (multiple sequencing) approach integrates changes at the transcriptional and translational level (RNA and proteins) and metabolic pathways, in response to dysbiosis. Such integrated approaches combining genetic, metabolic and environmental factors can uncover novel biomarkers to predict the course of the disease and treatment outcomes. Yet, these techniques have not been harnessed fully, due to their elaborate data interpretation and analysis, underscoring the scope for optimization of sequencing technologies and data processing for maximum output.
Finally, the review highlights therapeutic strategies such as “fetal microbiota transplantation” and “supplementary probiotics” that can help replenish gut microbiota and restore balance. Additional studies in this direction can help devise effective treatment regimens for IBD and associated disorders.
“Future efforts towards IBD associated intestinal micro-environment shifts should focus on the standardization of environmental confounding factors, like dietary and oral medications,” concludes Prof. Li.