Two novel compounds inhibit Flavivirus infection in vitro and in vivo by targeting lipid metabolism.

Flavivirus infection capitalizes on cellular lipid metabolism to remodel the cellular intima, creating a specialized lipid environment conducive to viral replication, assembly, and release. The Japanese encephalitis virus (JEV), a member of the Flavivirus genus, is responsible for significant morbidity and mortality in both humans and animals. Currently, there are no effective antiviral drugs available to combat JEV infection. In this study, we embarked on a quest to identify anti-JEV compounds within a lipid compound library. Our research led to the discovery of two novel compounds, isobavachalcone (IBC) and corosolic acid (CA), which exhibit dose-dependent inhibition of JEV proliferation. Time-of-addition assays indicated that IBC and CA predominantly target the late stage of the viral replication cycle. Mechanistically, JEV nonstructural proteins 1 and 2A (NS1 and NS2A) impede 5'-adenosine monophosphate (AMP)-activated protein kinase (AMPK) activation by obstructing the liver kinase B1 (LKB1)-AMPK interaction, resulting in decreased p-AMPK expression and a consequent upsurge in lipid synthesis. In contrast, IBC and CA may stimulate AMPK by binding to its active allosteric site, thereby inhibiting lipid synthesis essential for JEV replication and ultimately curtailing viral infection. Most importantly, in vivo experiments demonstrated that IBC and CA protected mice from JEV-induced mortality, significantly reducing viral loads in the brain and mitigating histopathological alterations. Overall, IBC and CA demonstrate significant potential as effective anti-JEV agents by precisely targeting AMPK-associated signaling pathways. These findings open new therapeutic avenues for addressing infections caused by Flaviviruses. IMPORTANCE: This study is the inaugural utilization of a lipid compound library in antiviral drug screening. Two lipid compounds, isobavachalcone (IBC) and corosolic acid (CA), emerged from the screening, exhibiting substantial inhibitory effects on the Japanese encephalitis virus (JEV) proliferation in vitro. In vivo experiments underscored their efficacy, with IBC and CA reducing viral loads in the brain and mitigating JEV-induced histopathological changes, effectively shielding mice from fatal JEV infection. Intriguingly, IBC and CA may activate 5'-adenosine monophosphate (AMP)-activated protein kinase (AMPK) by binding to its active site, curtailing the synthesis of lipid substances, and thus suppressing JEV proliferation. This indicates AMPK as a potential antiviral target. Remarkably, IBC and CA demonstrated suppression of multiple viruses, including Flaviviruses (JEV and Zika virus), porcine herpesvirus (pseudorabies virus), and coronaviruses (porcine deltacoronavirus and porcine epidemic diarrhea virus), suggesting their potential as broad-spectrum antiviral agents. These findings shed new light on the potential applications of these compounds in antiviral research.

Value of SLE-DAS in assessing disease activity in patients with systemic lupus erythematosus: a single-centre retrospective study.

OBJECTIVES: This study aimed to evaluate the clinical value of the Systemic Lupus Erythematosus Disease Activity Score (SLE-DAS) for assessing disease activity in patients with SLE. METHODS: Clinical data were collected from patients with SLE who were admitted at the Second Affiliated Hospital of Soochow University from January 2009 to December 2022. The glucocorticoid dose grading was used as the gold standard for disease activity assessment in SLE. The SLE-DAS value was calculated, and the SLE disease activity status was graded based on the SLE-DAS value. Another scoring criterion, the SLE Disease Activity Index 2000 (SLEDAI 2000), served as a control. Spearman correlation analysis was used to calculate the correlation between the scoring criteria and other variables. RESULTS: The analysis included 396 patients with SLE. A strong correlation was found between SLE-DAS and SLEDAI 2000 (ρ=0.709, 95% CI 0.648 to 0.766, p<0.001), with median SLE-DAS and SLEDAI 2000 scores of 15.32 (7.90 to 24.45) and 13 (8 to 19), respectively. Compared with the SLEDAI 2000 value, the SLE-DAS value correlated better with glucocorticoid dose grading (ρ=0.434 vs 0.518), gammaglobulin use (ρ=0.170 vs 0.318) and immunosuppressant use (ρ=0.122 vs 0.221). A moderate correlation based on disease activity grading was found between SLE-DAS and glucocorticoid dose grading (ρ=0.441), whereas a mild correlation was observed between SLEDAI 2000 and glucocorticoid dose grading (ρ=0.325). Additionally, SLE-DAS revealed a positive correlation with severe thrombocytopenia, cardiac involvement and pulmonary involvement but not SLEDAI 2000. CONCLUSION: Compared with SLEDAI 2000, SLE-DAS may provide a more accurate disease activity assessment in patients with SLE, especially those with severe thrombocytopenia and cardiopulmonary involvement.