Related Experiment Video
Updated: Jun 23, 2026
Electromagnetic Controlled Closed-Head Model of Mild Traumatic Brain Injury in Mice
Published on: September 28, 2022
Dymanics of matrix-metalloproteinase 9 after brain trauma--results of a pilot study
Martin Kolar1, Jan Pachl, Helena Tomasova
1Department of Anesthesiology and Critical Care Medicine, Charles University in Prague, Third Faculty of Medicine, Ruska 87, 100 34 Prague, 10, Czech Republic. martinuv.mail@seznam.cz
Background:
Secondary brain injury contributes to poor outcome for patients sustaining brain trauma. Matrix metalloproteinase-9 (MMP-9) is a potential marker, as well as effector of secondary brain injury. This enzyme degrades components of extracellular matrix, and thus it can contribute to blood-brain barrier disruption.
Methods:
We studied dynamics of MMP-9 in jugular venous blood of 15 patients sustaining either an isolated head injury or a head injury as a part of major trauma, and requiring intensive care (Glasgow Coma Scale <8 at the time of admission). Blood samples were taken at the 1st, 3rd and 5th day, levels of MMP-9 in plasma were assessed using ELISA. Outcome quality was assessed at the time of discharge from our hospital.
Findings:
Our results show an increase of MMP-9 levels on the 1st day after the brain trauma, followed by a drop on the 3rd day and a rise on day 5. This biphasic time-course was observed in all patients, but no statistically significant differences between each group (major trauma vs. isolated brain trauma, good outcome vs. poor outcome) were found.
Conclusions:
Initially increased MMP-9 levels in the 1st posttraumatic day is probably related to transient blood-brain barrier dysruption. The decrease of MMP-9 levels observed on the 3rd day can be explained by restoration of blood-brain barrier integrity and its reduced permeability. The second rise of MMP-9 levels observed in the 5th day probably indicates a developing secondary brain injury during which MMP-9 is produced in the brain as a part of an inflammatory response.
Results:
of our study suggest that MMP-9 could play an important role in pathogenesis of secondary brain injury.
Insights
Matrix metalloproteinase-9 (MMP-9) levels rise after brain trauma, indicating blood-brain barrier disruption. This biphasic pattern suggests MMP-9
Area of Science:
- Neuroscience
- Biochemistry
- Trauma Research
Background:
- Secondary brain injury significantly impacts patient outcomes after head trauma.
- Matrix metalloproteinase-9 (MMP-9) is implicated as both a marker and effector in secondary brain injury.
- MMP-9's enzymatic activity can degrade extracellular matrix, potentially leading to blood-brain barrier disruption.
Purpose of the Study:
- To investigate the dynamic changes in MMP-9 levels following brain trauma.
- To explore the relationship between MMP-9 levels and the development of secondary brain injury.
- To assess MMP-9 as a potential biomarker for blood-brain barrier integrity post-trauma.
Main Methods:
- Studied MMP-9 dynamics in jugular venous blood of 15 intensive care patients with Glasgow Coma Scale <8.
- Collected blood samples on days 1, 3, and 5 post-injury.
- Quantified plasma MMP-9 levels using ELISA and assessed patient outcomes at hospital discharge.
Main Results:
- Observed a biphasic pattern of MMP-9 levels: increased on day 1, decreased on day 3, and increased again on day 5.
- This temporal course of MMP-9 was consistent across all patients.
- No statistically significant differences in MMP-9 dynamics were found between isolated head trauma and major trauma groups, or between good and poor outcome groups.
Conclusions:
- Elevated MMP-9 on day 1 post-trauma likely reflects transient blood-brain barrier disruption.
- The subsequent decrease on day 3 may indicate blood-brain barrier repair.
- The rise in MMP-9 on day 5 suggests ongoing secondary brain injury and inflammation.
