Coumarin Derivative N6 as a Novel anti-hantavirus Infection Agent Targeting AKT

Hantavirus: an overview and advancements in therapeutic approaches for infection

Hantaviruses are a significant and emerging global public health threat, impacting more than 200,000 individuals worldwide each year. The single-stranded RNA viruses belong to the Hantaviridae family and are responsible for causing two acute febrile diseases in humans: Hantavirus pulmonary syndrome (HPS) and hemorrhagic fever with renal syndrome (HFRS). Currently, there are no licensed treatments or vaccines available globally for HTNV infection. Various candidate drugs have shown efficacy in increasing survival rates during the early stages of HTNV infection. Some of these drugs include lactoferrin, ribavirin, ETAR, favipiravir and vandetanib. Immunotherapy utilizing neutralizing antibodies (NAbs) generated from Hantavirus convalescent patients show efficacy against HTNV. Monoclonal antibodies such as MIB22 and JL16 have demonstrated effectiveness in protecting against HTNV infection. The development of vaccines and antivirals, used independently and/or in combination, is critical for elucidating hantaviral infections and the impact on public health. RNA interference (RNAi) arised as an emerging antiviral therapy, is a highly specific degrades RNA, with post-transcriptional mechanism using eukaryotic cells platform. That has demonstrated efficacy against a wide range of viruses, both in vitro and in vivo. Recent antiviral methods involve using small interfering RNA (siRNA) and other, immune-based therapies to target specific gene segments (S, M, or L) of the Hantavirus. This therapeutic approach enhances viral RNA clearance through the RNA interference process in Vero E6 cells or human lung microvascular endothelial cells. However, the use of siRNAs faces challenges due to their low biological stability and limited in vivo targeting ability. Despite their successful inhibition of Hantavirus replication in host cells, their antiviral efficacy may be hindered. In the current review, we focus on advances in therapeutic strategies, as antiviral medications, immune-based therapies and vaccine candidates aimed at enhancing the body's ability to control the progression of Hantavirus infections, with the potential to reduce the risk of severe disease.

Natural Antioxidant Compounds as Potential Pharmaceutical Tools against Neurodegenerative Diseases

Natural antioxidants are a very large diversified family of molecules classified by activity (enzymatic or nonenzymatic), chemical-physical properties (e.g., hydrophilic or lipophilic), and chemical structure (e.g., vitamins, polyphenols, etc.). Research on natural antioxidants in various fields, such as pharmaceutics, nutraceutics, and cosmetics, is among the biggest challenges for industry and science. From a biomedical point of view, the scavenging activity of reactive oxygen species (ROS) makes them a potential tool for the treatment of neurodegenerative diseases including Alzheimer's disease, Parkinson's disease, Huntington's disease, dementia, and amyotrophic lateral sclerosis (ALS). In addition to the purified phytochemical compounds, a variety of natural extracts characterized by a complex mixture of antioxidants and anti-inflammatory molecules have been successfully exploited to rescue preclinical models of these diseases. Extracts derived from Ginkgo biloba, grape, oregano, curcumin, tea, and ginseng show multitherapeutic effects by synergically acting on different biochemical pathways. Furthermore, the reduced toxicity associated with many of these compounds limits the occurrence of side effects. The support of nanotechnology for improving brain delivery, controlling release, and preventing rapid degradation and excretion of these compounds is of fundamental importance. This review reports on the most promising results obtained on in vitro systems, in vivo models, and in clinical trials, by exploiting natural-derived antioxidant compounds and extracts, in their free form or encapsulated in nanocarriers.

In vitro Anti-Hantavirus Activity of Protein Kinase Inhibitor 8G1 Targeting AKT/mTOR/eIF4E Signaling Pathway

Hantaan virus (HTNV) is the main cause of hemorrhagic fever with renal syndrome (HFRS) around the world, which results in profound morbidity and mortality. However, there are currently no FDA-approved therapeutics or vaccines against HFRS. To find new anti-HTNV drugs, the inhibitory activity of 901 small molecule kinase inhibitors against HTNV is analyzed. Among these compounds, compound 8G1 inhibits HTNV with a relatively high inhibition rate and lower toxicity. The viral titer and nucleocapsid protein of HTNV are reduced after compound 8G1 treatment in a dose-dependent manner at concentrations ranging from 1 to 20 μM. In addition, the administration of compound 8G1 at the early stage of HTNV infection can inhibit the replication of HTNV. The molecular docking result reveals that compound 8G1 forms interactions with the key amino acid residues of serine/threonine-protein kinase B (Akt), which is responsible for the observed affinity. Then, the mammalian target of rapamycin (mTOR) and eukaryotic translation initiation factor 4E (eIF4E) signaling pathways are inhibited. Our results may help to design novel targets for therapeutic intervention against HTNV infection and to understand the anti-HTNV mechanism of protein kinase inhibitors.

LncRNA NEAT1 Potentiates SREBP2 Activity to Promote Inflammatory Macrophage Activation and Limit Hantaan Virus Propagation

As the global prototypical zoonotic hantavirus, Hantaan virus (HTNV) is prevalent in Asia and is the leading causative agent of severe hemorrhagic fever with renal syndrome (HFRS), which has profound morbidity and mortality. Macrophages are crucial components of the host innate immune system and serve as the first line of defense against HTNV infection. Previous studies indicated that the viral replication efficiency in macrophages determines hantavirus pathogenicity, but it remains unknown which factor manipulates the macrophage activation pattern and the virus-host interaction process. Here, we performed the transcriptomic analysis of HTNV-infected mouse bone marrow-derived macrophages and identified the long noncoding RNA (lncRNA) nuclear enriched abundant transcript 1 (NEAT1), especially the isoform NEAT1-2, as one of the lncRNAs that is differentially expressed at the early phase. Based on coculture experiments, we revealed that silencing NEAT1-2 hinders inflammatory macrophage activation and facilitates HTNV propagation, while enhancing NEAT1-2 transcription effectively restrains viral replication. Furthermore, sterol response element binding factor-2 (SREBP2), which controls the cholesterol metabolism process, was found to stimulate macrophages by promoting the production of multiple inflammatory cytokines upon HTNV infection. NEAT1-2 could potentiate SREBP2 activity by upregulating Srebf1 expression and interacting with SREBP2, thus stimulating inflammatory macrophages and limiting HTNV propagation. More importantly, we demonstrated that the NEAT1-2 expression level in patient monocytes was negatively correlated with viral load and HFRS disease progression. Our results identified a function and mechanism of action for the lncRNA NEAT1 in heightening SREBP2-mediated macrophage activation to restrain hantaviral propagation and revealed the association of NEAT1 with HFRS severity.