Chondroitinase ABC reduces brain tissue swelling in vitro

Area of Science:

• Neuroscience
• Biochemistry
• Medical Research

Background:

• Increased intracranial pressure (ICP) from edema after traumatic brain injury (TBI) or stroke leads to significant mortality.
• Current treatments for brain edema and ICP remain insufficient.
• Previous work linked brain tissue fixed charge density (FCD) to swelling via the Donnan effect.

Purpose of the Study:

• To investigate if reducing brain tissue FCD can mitigate swelling and edema.
• To evaluate the efficacy of enzymes targeting FCD components in reducing brain swelling.
• To assess the potential of Chondroitinase ABC (ChABC) as a therapeutic agent for brain edema.

Main Methods:

• Enzymatic digestion of chondroitin sulfate proteoglycans (CSPGs), heparin sulfate proteoglycans (HSPGs), and DNA in rat cortical slices.
• Measurement of FCD and tissue swelling over 24 hours post-dissection.
• Assessment of ChABC's effect on live rat and porcine cortical tissue swelling in response to osmotic changes.

Main Results:

• Enzymatic treatments reduced FCD by approximately 20% and tissue swelling from ~60% to ~30% in 24 hours.
• Chondroitinase ABC (ChABC) was most effective in reducing swelling in dead and live brain tissue, including rapid reduction within 2 hours.
• ChABC significantly decreased FCD and swelling in porcine brain tissue exposed to hypotonic solutions.

Conclusions:

• Reducing brain tissue FCD is a viable strategy for decreasing edema and swelling.
• ChABC demonstrates significant potential for reducing brain edema and controlling ICP following injury.
• Enzymatic modulation of FCD offers a promising therapeutic avenue for managing brain swelling.