Biotechnologically obtained bacterial melanin (BM) has been extensively studied as a potential pharmacological preparation with neuroprotective and anti-inflammatory effects. Anti-inflammatory action of BM was tested in animal model of induced encephalomyelitis. The goal of presented research was to examine anti-inflammatory potential of BM in lipopolysaccharide-stimulated murine RAW 264.7 cells. The cells were treated with different concentrations of BM (from 6 mg/ml to 4, 2 and 1 mg/ml) and incubated for 20 hours. Results were compared with data obtained from vehicle control treated cells. Two tailed t-test was used to evaluate the results. The obtained data showed that BM reduces the production of nitric oxide and prostaglandin E2. The substance suppresses production of pro-inflammatory cytokines including interleukin (IL)-6 and IL-1b.
The results revealed that BM has anti-inflammatory activity and has a potential to suppress neuroinflammation. Brain macrophages-are the only cells that mediate brain inflammation. Extracellular neuromelanin can activate the CNS microglia inducing neuroinflammation and neurodegeneration. The water-soluble biotechnological melanin does not activate microglia – the resident brain macrophages.
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