IQUIBICEN   23947
INSTITUTO DE QUIMICA BIOLOGICA DE LA FACULTAD DE CIENCIAS EXACTAS Y NATURALES
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Inhibitors of p38 as antiviral compounds against Junín virus infection in cell cultures
Autor/es:
QUINTANA VM; BRUNETTI JE; CASTILLA V; SCOLARO LA
Lugar:
Buenos Aires
Reunión:
Congreso; Drug Discovery for Neglected Diseases International Congress 2018. 4th Scientific Meeting of Research Network of Natural Products against Neglected Diseases; 2018
Resumen:
Junín virus (JUNV) is the aetiological agent of Argentine Haemorrhagic Fever (FHA) and no specific antiviral therapy iscurrently available for FHA treatment. Numerous viruses are able to activate mitogen-activated protein kinase (MAPK)-dependent cell signalling pathways, which are potential targets for the development of new antiviral strategies [1]. Wehave previously demonstrated that JUNV modulates ERK cell signalling pathway to ensure an efficient multiplication [2].p38, another MAPK pathway, which is activated in response to growth factors, stress and viral infections, is involved inapoptosis induction and proinflammatory cytokines production. In the present study we analysed the ability of JUNVto modulate p38 phosphorylation and we evaluated the effect of p38 inhibitors on JUNV multiplication in Vero cellcultures.We first infected Vero cells with JUNV and at different time points we examined the level ofphospho-p38 by westernblot (WB). JUNV induced a weak activation of p38 cellular pathway at early times post-infection whereas a stronger p38activation was evident at late stages of infection.Next, we evaluated the cytotoxic and antiviral activities of two p38 inhibitors: SB203580, a compound that impairs p38activity, and SB202190, which inhibits both the phosphorylation and the activity of p38 [3]. Prior to study their antiviraleffect, Vero cell cultures were treated with different concentrations of each compound and after 24h we determinedcell viability by the MTT assay. After that, to examine whether these inhibitors affect JUNV multiplication, cell culturesinfected with JUNV were treated with different non-cytotoxic concentrations of SB203580or SB202190 for 24 handinfectious viral production was quantified by a plaque formation assay. A significant and dose-dependent reductionof viral yield was achieved in treated cultures indicating that the inhibition of p38 impaired JUNV multiplication. Weverified the effect of inhibitors on p38 pathway by analysing, by WB, the level of phosphorylation of MAPKAPK-2, adownstream kinase of p38 cascade.In addition, we analysed the expression of the viral nucleoprotein (N), by indirect immunofluorescence assays, inJUNV- infected cells treated with SB203580 or SB202190 and we determined that both compounds diminished thepercentage of N expressing cells compared to untreated infected cultures. A dose-dependent inhibition of N proteinexpression in cells treated with the compound SB203580 was also determined by WB.In conclusion, our results indicate that JUNV induces the activation of p38 signalling pathway and also demonstratethat p38 activation would be relevant for JUNV productive infection.