Authors: Ellie P. Evans, Mmadili Ilozumba, Sheetal Hardikar, Neli Ulrich, Jennifer Ose
Mentors: Mmadili Ilozumba
Insitution: Utah Valley University
Cachexia is a complex syndrome characterized by severe weight loss and muscle wasting. It is also a prevalent complication in various chronic diseases, including cancer and acquired immunodeficiency syndrome. Recent research has underscored the pivotal role of the gut microbiome in systemic well-being. Furthermore, it has been shown that cancer patients suffering from cachexia have unique bacteria composition in the gut compared to that of non-cachectic patients. In the absence of stool samples, there are a few metabolites in the circulatory system that can be directly linked to gut microbiota. Examples include bile acids, and short chain fatty acids as metabolites produced by specific Phylum. The presence of these gut microbiota derived metabolites (GMDM) in the circulation indicate a compromise in the integrity of tight junctions in the intestines. These results prompted an investigation of GMDM as an indicator of gut permeability. Our hypothesis is that an increased concentration of GMDM in the circulation is linked to gut permeability, leading to the development of cachexia in patients with colorectal cancer.
This literature review provides a comprehensive analysis of the relationship between gut permeability and cachexia, seeking to identify which GMDMs are the most accurate indicators of specific bacteria linked to gut permeability, and subsequently, are accurate projectors of cachexia.
Acetic acid, a short chain fatty acid (SCFA) is a GMDM detected in the plasma of patients with gut permeability. Acetic acid makes up about 60% of the SCFAs produced by a healthy gut flora and 90% of it is produced by the genus Bifidobacterium. Our literature review will cover how closely a measurement of acetic acid and other GMDMs measured in plasma can be linked to gut permeability and to Bifidobacterium levels in the gut. Similarly, Indole is a GMDM produced by Escherichia coli and other indole-producing bacteria. Indole isn’t produced naturally anywhere else in the body. When it is naturally absorbed into the liver through the portal vein, it’s mostly converted into indoxyl sulfate. The heightened presence indole in plasma in sulfate-free forms could indicate that indole is being absorbed through holes in the tight junctions of the intestines, rather than through the portal vein.
This information would allow cohorts that have collected plasma samples in the past to measure gut permeability by proxy, even if they’re unable to investigate the gut microbiota and metabolites present from stool samples. These connections found could further help us to use-already collected samples to find accurate biomarkers for early cachexia development in cancer patients.
If an oral presentation is unavailable, a poster presentation would be great.