In-vitro Effects of Bacterial Melanin in Macrophage “RAW 264.7” Cell Culture

Article type: Research Article

Authors: Petrosyan, Tigran^{a; *} | Hovsepyan, Anichka^b | Avetisyan, Sona^b | Kurian, Noble^c

Affiliations: [a] Yerevan State Medical University, Yerevan, Armenia | [b] SPC “Armbiotechnology” SNPO NAS, Republic of Armenia | [c] Cochin University of Science and Technology, Cochin, India

Correspondence: [*] Correspondence to: T.R. Petrosyan, 6 Orbeli Street, 88, Yerevan, Armenia. Tel.: +374 93734579; E-mail: tigpetrosyan@mail.ru.

Abstract: 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.

Keywords: Bacterial melanin, inflammation, level of cytokines, nitric oxide, cyclooxygenase

DOI: 10.3233/NIB-190162

Journal: Advances in Neuroimmune Biology, vol. 7, no. 3-4, pp. 199-206, 2019