HSP90 inhibitor NVP-HSP990 alleviates rotavirus infection

Rotavirus (RV) infection is a significant cause of hospitalization and mortality in infants and young children. Although conventional symptomatic treatments usually appear effective, tens of thousands of infants and young children still die each year due to the absence of safe and effective anti-RV drugs. Heat shock protein 90 (HSP90) is usually required for efficient viral infection; however, due to unsatisfactory antiviral efficacy and toxicity, there has been no HSP90-targeting agents applied for clinical antiviral therapy currently. Here, we demonstrated that NVP-HSP990, a novel small-molecule HSP90 inhibitor with excellent oral bioavailability and brain penetration, was a potent inhibitor of RV infection with much bigger selectivity index (SI) than traditional HSP990 inhibitors. NVP-HSP990 potently inhibited RV replication in vitro without blocking infection establishment. NVP-HSP990 remarkably restored gene expressions of most KEGG pathways disturbed by RV infection in intestinal cells, except some inflammatory pathways (IL-17, TNF, etc.). To be noted, NVP-HSP990 significantly altered gene expressions in MAPK signaling pathway and inhibited RV-induced activation of MAPK as well as disruption of tight junctions in Caco-2 cells. More importantly, NVP-HSP990 effectively alleviated RV diarrhea, competently inhibited RV replication, and obviously prevented pathological lesions of intestine in BALB/c suckling mice. Therefore, our results suggested that NVP-HSP990 can be a promising antiviral drug candidate against RV infection. ### Competing Interest Statement The authors have declared no competing interest. * 17-AAG : 17-allylamino-17-demethoxygeldanamycin 17-DMAG : N-dimethylaminoethyl-17-methoxygeldanamycin ANOVA : analysis of variance ATCC : American type culture collection CCK-8 : cell counting kit-8 CC50 : 50% cytotoxic concentration COVID-19 : Corona Virus Disease 2019 DAPI : 2-(4-Amidinophenyl)-6-indolecarbamidine dihydrochloride DMEM : Dulbecco’s modified eagle medium DMSO : dimethyl sulfoxide DTT : dithiothreitol EC50 : concentration for 50% of maximal effect ELISA : enzyme-linked immunosorbent assay ERK : extracellular signal-regulated kinase FBS : fetal bovine serum FITC : fluorescein 5-isothiocyanate FPKM : fragment per kilobase of transcript per million mapped reads GA : geldanamycin GRP94 : glucose-regulated protein 94 HSP90 : heat shock protein 90 IC50 : half maximal inhibitory concentration IFA : immunofluorescence assay IL-17 : interleukin 17 JNK : c-Jun N-terminal kinase KEGG : Kyoto Encyclopedia of Genes and Genomes MAPK : mitogen-activated protein kinase MOI : multiplicity of infection p38 : p38 mitogen-activated protein kinase PFA : plaque formation assay PFU : plaque formation unit qPCR : quantitative Real-time PCR RV : rotavirus RNA-seq : RNA-sequencing SI : selectivity index TNF : tumor necrosis factor TRAP1 : TNF receptor associated protein 1 WHO : world health organization.