Bacterial melanin crosses the blood–brain barrier in rat experimental model

This study investigates whether bacterial melanin (BM) can cross the blood-brain barrier (BBB) in rats. The BBB is a protective barrier that restricts the passage of substances from the bloodstream into the brain. The study uses radioactively labeled BM to track its movement into the brain after injection into rats. The results show that BM can indeed cross the BBB. Furthermore, the entry of BM into the brain is reduced when non-labeled BM is also present, suggesting a saturable transport mechanism. This means there's a limit to how much BM can be transported across the BBB at a given time. The study also found that BM distributes throughout the central nervous system (CNS), with higher uptake in specific regions like the lumbar spinal cord, thalamus, hypothalamus, and substantia nigra. These findings suggest that BM could potentially be used as a neuroprotective agent, targeting specific areas of the brain.

• 1
  Radioactively-labeled bacterial melanin crosses the blood–brain barrier and is enzymatically stable in blood and brain parenchyma.
• 2
  Entry to brain was reduced when non-labeled BM was also present, indicating a saturable transport system.
• 3
  Circulating melanin entered all regions of the CNS, with higher uptake in the lumbar spinal cord, thalamus, hypothalamus, and substantia nigra.