TRAUMATIC BRAIN INJURY-INDUCED INFLAMMATION AND GASTROINTESTINAL MOTILITY DYSFUNCTION

Area of Science:

• Neuroscience
• Immunology
• Gastroenterology

Background:

• Traumatic brain injury (TBI) is a major cause of death and disability in the US, costing $60 billion annually.
• The gastrointestinal tract may drive organ and immune dysfunction post-TBI, releasing proinflammatory mediators.
• Systemic inflammation and bacterial dysbiosis are implicated in TBI outcomes.

Purpose of the Study:

• To investigate systemic inflammation and bacterial changes in TBI patients.
• To explore the link between neuroinflammation and gut homeostasis disruptions (intestinal transit, inflammation) in a mouse model of TBI.

Main Methods:

• Blood and stool samples from TBI patients (n=12 plasma, n=10 stool) and healthy controls were analyzed for inflammatory markers and bacterial composition.
• A mouse model of TBI was used to assess neuroinflammation, intestinal transit, and bacterial changes 24 hours post-injury.
• Analysis included measuring cytokine levels (IFN-γ, MCP-1, IL-6, IL-8, IL-4, TNF-α, IL-1β, IL-10) and bacterial copy numbers (Enterobacteriaceae, Lactobacillus, Bilophila wadsworthia).

Main Results:

• TBI patients exhibited increased systemic inflammation (IFN-γ, MCP-1) and decreased IL-4 compared to controls.
• A significant increase in Bilophila wadsworthia was observed in TBI patients.
• TBI mice showed increased neuroinflammation (TNF-α, IL-6, IL-1β) and decreased intestinal transit with increased TNF-α in the small intestine.

Conclusions:

• TBI is associated with increased systemic inflammation, neuroinflammation, and intestinal dysfunction.
• Findings suggest a potential role for altered intestinal motility in post-TBI neuroinflammation and cognitive deficits.
• Further research is needed to confirm the relationship between intestinal motility and TBI-induced neuroinflammation.