Suppression of Zika Virus Infection and Replication in Endothelial Cells and Astrocytes by PKA Inhibitor PKI 14-22

Abstract

The recent outbreak of Zika virus (ZIKV), a reemerging flavivirus, and its associated neurological disorders, such as Guillain-Barré (GB) syndrome and microcephaly, have generated an urgent need to develop effective ZIKV vaccines and therapeutic agents. Here, we used human endothelial cells and astrocytes, both of which represent key cell types for ZIKV infection, to identify potential inhibitors of ZIKV replication. Because several pathways, including the AMP-activated protein kinase (AMPK), protein kinase A (PKA), and mitogen-activated protein kinase (MAPK) signaling pathways, have been reported to play important roles in flavivirus replication, we tested inhibitors and agonists of these pathways for their effects on ZIKV replication. We identified the PKA inhibitor PKI 14-22 (PKI) to be a potent inhibitor of ZIKV replication. PKI effectively suppressed the replication of ZIKV from both the African and Asian/American lineages with a high efficiency and minimal cytotoxicity. While ZIKV infection does not induce PKA activation, endogenous PKA activity is essential for supporting ZIKV replication. Interestingly, in addition to PKA, PKI also inhibited another unknown target(s) to block ZIKV replication. PKI inhibited ZIKV replication at the postentry stage by preferentially affecting negative-sense RNA synthesis as well as viral protein translation. Together, these results have identified a potential inhibitor of ZIKV replication which could be further explored for future therapeutic application.IMPORTANCE There is an urgent need to develop effective vaccines and therapeutic agents against Zika virus (ZIKV) infection, a reemerging flavivirus associated with neurological disorders, including Guillain-Barré (GB) syndrome and microcephaly. By screening for inhibitors of several cellular pathways, we have identified the PKA inhibitor PKI 14-22 (PKI) to be a potent inhibitor of ZIKV replication. We show that PKI effectively suppresses the replication of all ZIKV strains tested with minimal cytotoxicity to human endothelial cells and astrocytes, two key cell types for ZIKV infection. Furthermore, we show that PKI inhibits ZIKV negative-sense RNA synthesis and viral protein translation. This study has identified a potent inhibitor of ZIKV infection which could be further explored for future therapeutic application.

The celecoxib derivative kinase inhibitor AR-12 (OSU-03012) inhibits Zika virus via down-regulation of the PI3K/Akt pathway and protects Zika virus-infected A129 mice: A host-targeting treatment strategy

“…Another recent study reported that the activation of adenosine monophosphate-activated protein kinase by a small molecule activator (PF-06409577) inhibited ZIKV replication through modulation of host cell lipid metabolism (Jiménez de Oya et al, 2018). These findings supported our hypothesis that drugs which target host signaling pathways may be useful for treating ZIKV infection (Cheng et al, 2018).…”

Variations in maternal adenylate cyclase genes are associated with congenital Zika syndrome in a cohort from Northeast, Brazil

“…Moreover, in the context of ZIKV infection, higher levels of cAMP could not only stimulate virus replication but also affect placental innate immunity as previously shown, facilitating mother‐to‐child transmission . Recent data also show that inhibition of cAMP downstream effectors suppress ZIKV replication, supporting the relevance of cAMP levels on ZIKV pathogenesis .…”

Host-Directed Antivirals: a Realistic Alternative to Fight Zika Virus

“…Regarding sphingolipid metabolism, which has been involved in flavivirus infection [64], treatment with the neutral sphingomyelinase inhibitor GW4869 reduced ZIKV production by affecting viral morphogenesis [108] as described for other flaviviruses [109]. Finally, the activation of adenosine monophosphate-activated protein kinase (AMPK), a master regulator of lipid metabolism, using PF-06409577 or metformin reduced ZIKV infection, being its effect associated to an impairment of viral replication due to the modulation of the host cell lipid metabolism exerted by the compound [110,111]. Thus, targeting lipid metabolism could provide therapeutic alternatives for the discovery of host-directed antivirals against ZIKV.…”