In a recent review the literature, researchers at the Walter Reed Army Institute of Research identified the establishment of a protective gut microbiota as a “compelling therapeutic avenue” for the treatment of traumatic brain injury (TBI).

In a January 23, 2018 post this author summarized evidence that a TBI can trigger pathology in the Gut-Brain Axis and increase infections.  The Walter Reed researchers dive deeper into this issue. Summarizing the research, they explain that “brain injury induces disruptions in the composition of the gut microbiota, i.e. gut dysbiosis, which has been shown to contribute to TBI-related neuropathology and impaired behavioral outcomes.” (emphasis added.)

The gut microbiome, they explain, is involved in the control of a multitude of cellular and molecular processes involved in the progression of TBI-induced pathologies “including neuroinflammation, blood brain barrier permeability, immune system response, microglial activation, and mitochondrial dysfunction, as well as intestinal motility and permeability.” Significantly, TBI induced disruption in gut microbiota can aggregate behavioral impairments, including anxiety and depression.

The growing evidence of the role of the gut in the body’s response to TBI offers a promising area for developing future therapies. Recent animal studies show that microbiota transplants and probiotic treatment can reduce neuroanatomical damage and functional impairments after stroke and spinal cord injury. Probiotics have also been shown to improve behavior and cognition in individuals with Alzheimer’s disease and depression. The use of similar treatments in patients with TBI, the researchers conclude, offers “compelling” promise.

Before realizing this promise, however, more work is needed to understand the specific changes that occur in the gut microbiota following different types and severities of TBI, as well as optimal doses, treatment window, duration of treatment and the efficacy of treatment across age and gender.