Effect of Prophylactic Use of Intranasal Oil Formulations in the Hamster Model of COVID-19

Abstract

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection initiates with viral entry in the upper respiratory tract, leading to coronavirus disease 2019 (COVID-19). Severe COVID-19 is characterized by pulmonary pathologies associated with respiratory failure. Thus, therapeutics aimed at inhibiting the entry of the virus or its internalization in the upper respiratory tract are of interest. Herein, we report the prophylactic application of two intranasal formulations provided by the National Medicinal Plant Board (NMPB), Anu oil and til tailya, in the hamster model of SARS-CoV-2 infection. Prophylactic intra-nasal instillation of these oil formulations exhibited reduced viral load in lungs and resulted in reduced body weight loss and lung-pneumonitis. In line with reduced viral load, histopathological analysis revealed a reduction in lung pathology in the Anu oil group as compared to the control infected group. However, the til tailya group did not show a significant reduction in lung pathology. Furthermore, molecular analysis using mRNA expression profiling indicated reduced expression of pro-inflammatory cytokine genes, including Th1 and Th17 cytokines for both the intranasal formulations as a result of decreased viral load. Together, the prophylactic intranasal application of Anu oil seems to be useful in limiting both viral load and severity in SARS-CoV2 infection in the hamster model.

Prophylactic treatment of Glycyrrhiza glabra mitigates COVID-19 pathology through inhibition of pro-inflammatory cytokines in the hamster model and NETosis

“…Heightened levels of pro-inflammatory cytokines lead to tissue injury characteristic of severe cases of COVID-19 (35–37). In line with clinical cases, hamster infected with SARS-CoV-2 shows elevated levels of pro-inflammatory cytokine at 4 dpi as previously reported (24, 38). To understand the immunomodulatory effect of GG on SARS-CoV-2 infected hamsters, we investigated splenomegaly condition and evaluated the cytokine and transcription factor expression in the splenocytes.…”

“…Instillation of Ayurvedic herb, Anu oil exhibited reduced SARS-CoV-2 load and the expression of pro-inflammatory cytokine genes (Th1 and Th17) in the lungs (38). Recent reports have shown upregulation in IL-6 from human neutrophils using TLR8 ligand, resiquimod, and IFNα (65).…”

A combination of potently neutralizing monoclonal antibodies isolated from an Indian convalescent donor protects against the SARS-CoV-2 Delta variant

“…Antibody recipient groups were given intraperitoneal injection of IgG one day prior to challenge (day -1). Except for the unchallenged control group (n = 3), animals in all other groups were challenged with 10 5 PFU of SARS-CoV2 (Wuhan and Delta isolates) intranasally on Day 0, administered through a catheter 25 μl/ nare under anesthesia by using ketamine (150mg/kg) and xylazine (10mg/kg) inside ABSL3 facility [ 36 , 50 – 52 ]. Unchallenged control group received mock PBS (pH 7.4) intranasally.…”

Anti-COVID-19 Activity of FDA Approved Drugs through RNA G-quadruplex Binding

“…To check the effect of the G4 binding ligands as potential molecules for therapeutic intervention in COVID-19 treatment we used SARS-CoV-2 infection in hamsters as previously described (Chan et al, 2020;Rizvi et al, 2022Rizvi et al, , 2021Sia et al, 2020). Both prophylactic and therapeutic regimens of CPZ and PCZ treatment were tested.…”

“…All the animals were euthanized on day 4 post challenge, which has been shown earlier as the optimal time point to study SARS-CoV-2 lung pathology in hamsters (Rizvi et al, 2022(Rizvi et al, , 2021.…”