Biology subjects

Subudhi, B. B.

Publications and source records attributed to Subudhi, B. B..

5 recordsLinked to original sources

bioRxiv2026

Neuropilin-1 functions as a proviral and immunoregulatory host factor during Chikungunya virus infection

Neuropilin-1 (NRP1) is a transmembrane glycoprotein involved in angiogenesis, neurodevelopment, inflammation, cancer driven immune suppression, and immune homeostasis. However, its contribution to virus-induced immune responses is not explored. Chikungunya virus (CHIKV) is a re-emerging arthritogenic alphavirus that causes severe arthralgia, and myalgia, accompanied by heightened inflammatory cytokine responses. The host factors that drive these inflammatory responses, however, remain poorly defined. Here, in this current study, the role of NRP1 in CHIKV infection was investigated using in vitro, and in vivo model systems. Using genetic manipulation, pharmacological, and antibody blockade-mediated approaches in murine and human cellular infection models, it was demonstrated that NRP1 promotes CHIKV infection while restraining the production of proinflammatory cytokines. Furthermore, NRP1 inhibition selectively increased JNK phosphorylation. Hence, inhibiting JNK reduced the elevated cytokine production caused by NRP1 blockade. Moreover, NRP1 interacted with CHIKV-E1 and is involved in multiple phases of CHIKV infection. In addition, it was demonstrated that NRP1 inhibition using EG00229 trifluoroacetate can reduce viral infection in several CHIKV-susceptible cells, human peripheral blood macrophages, and in the in vivo mice model of infection. Together, these findings indicate that NRP1 is an important host factor and a probable therapeutic target during CHIKV infection. IMPORTANCEChikungunya virus (CHIKV) causes acute febrile illness that can progress to debilitating chronic musculoskeletal and occasional neurological complications. The absence of a globally available effective vaccine and the lack of specific antivirals underscore CHIKV as a major burden, especially in endemic tropical regions. There is a growing need to understand host factors that shape CHIKV-driven immune response. The importance of our study lies in understanding the immunoregulatory role of the host receptor Neuropilin-1 (NRP1) during CHIKV infection. We identify NRP1 as a novel host factor of CHIKV infection that also acts as a rheostat to restrict the inflammatory viral immune response. Moreover, we report anti-viral potential of the NRP1 antagonist EG00229 trifluoroacetate in multiple cell lines, primary cells, and mice model. Our findings indicate NRP1 as a probable therapeutic target in CHIKV pathogenesis.

immunology↗

bioRxiv2024

Telmisartan impedes JEV infection predominately via AT1/PPARγ axis

Japanese encephalitis, caused by Japanese encephalitis virus (JEV) is a vector born disease for which no specific therapeutics are available yet. Binding of angiotensin II (Ang II) to angiotensin II type 1 (AT1) receptor induces release of inflammatory cytokines associated with viral encephalitis. Accordingly, Ang II receptor blockers (ARBs) have been proposed to manage encephalitis. Since Telmisartan (TM, antagonist of AT1 and agonist of PPAR{gamma}) has relatively better brain access than other ARBs, this investigation aims to evaluate its anti-JEV efficacy in vitro and in vivo. TM reduced JEV titer, RNA and protein (NS3) significantly in the BHK-21 cells with IC50 of 24.68M and CC50 of >350 M (Selectivity Index >14.18) indicating its potential of repurposing against JEV. The anti-JEV efficacy of TM was further observed in macrophages (RAW264.7) and neuronal (SH-SY5Y) cells. Interestingly, the viral load was reduced significantly in pre, co and post-treatment conditions of TM, however most efficiently (80%) in post treatment. In presence of GW (PPAR{gamma} antagonist) and AG (AT1 agonist), viral infection was increased remarkably while AT1 was upregulated and PPAR{gamma} was downregulated. Whereas, TM treatment reversed the levels of AT1 and PPAR{gamma} during infection. Further, reduction of inflammatory markers like p-IRF-3, COX-2 and p-NF-{kappa}B was observed after TM treatment in RAW264.7 cells suggesting its immunomodulation through the AT1/PPAR{gamma} axis. Finally, the anti-JEV potential of TM was validated in mice model through the reduction of disease score, viral protein and histological changes. Thus, the preclinical efficacy of TM suggests its suitability for repurposing against JEV.

microbiology↗

bioRxiv2023

The uniqueness of the Brazilian Yellow Fever Virus. Are the vaccines less effective against it?

The years 2016-2019 witnessed the expansion of Yellow Fever Virus (YFV) circulation area in Brazil. Deforestation and mutations in the nsp genes were presumed responsible for the reemergence of YFV in brazil. However, our data analysis involving 200 clinical isolates worldwide including vaccine strains showed two amino acids substitutions exclusively in the Brazilian strains at critical positions (V318A and I335M) in the ED III domain of E protein. Our molecular dynamics analysis involving reference and mutant structures suggests that the mutations significantly changed the conformational rearrangement and folding of the YFV-EDIII domain as revealed by RMSF, PCA, Porcupine plots and secondary structure analysis. Briefly, the regions 324-330, 339-346 and 347-359 had a higher fluctuation than the wild, while regions 313-318 and 379-384 had a lower fluctuation. As reported earlier that the residues E325 and E380 are part of vaccine epitopes and any mutations in these residues reduced the binding of vaccine generated mabs to the epitopes. Hence, it may be speculated from our porcupine plot data analysis that that the commercial YFV vaccines may not be fully effective against the Brazilian strains in particular owing to the fluctuations of these residues. However, future investigation is required to validate the observations.

microbiology↗

bioRxiv2022

DNA damage response signaling is crucial for effective Chikungunya virus replication

Viruses utilize a plethora of strategies to manipulate the host pathways and hijack its machineries for efficient replication. Several DNA as well as handful of RNA viruses are reported to interact with proteins involved in DNA damage responses (DDR). As the DDR pathways have never been explored in Alphaviruses, this investigation intended to determine the importance of the DDR pathways in CHIKV infection through in vitro, in vivo and ex vivo models. The study reveals that CHIKV infection activates the Chk2 and Chk1 proteins associated with DDR signaling pathways and increases DNA damage by 95%. Inhibition of both ATM-ATR kinases by ATM/ATR kinase inhibitor (AAKi) shows drastic reduction in viral particle formation in vitro. Next, the treatment of mice with this drug has been shown to reduce the disease score substantially in CHIKV-infected C57BL/6 mice with 71% decrement in the viral copy and the same has been established in hPBMC-derived monocyte-macrophage populations. Additionally, gene silencing of Chk2 and Chk1 reduces viral progeny formation around 73.7% and 78% respectively. Moreover, it has been demonstrated that CHIKV-nsP2 interacts with Chk2 and Chk1 during CHIKV infection and docking analysis depicts the specific amino acids responsible for these interactions. Further, the data suggests that CHIKV infection induces cell cycle arrest in G1 and G2 phases. In conclusion, this work demonstrated for the first time the mechanistic insight of the induction of DDR pathways by CHIKV that might contribute to the designing of effective therapeutics for the control of this virus infection in future. IMPORTANCEViruses being intra-cellular parasite, need several host cell machineries so as to achieve effective replication of their own genome, along with virus-encoded enzymes. One of the strategies is to hijack the DDR pathways. Several DNA as well as handful of RNA viruses interact with the cellular proteins involved in DDR pathways, however, reports with respect to the association of Chk2 and Chk1 in alphavirus infection are scanty. Hence, this study is amongst the first to report that modulation of DDR pathways is crucial for effective CHIKV infection. This work also shows that there is interaction of CHIKV-nsP2 with two crucial host factors, Chk2 and Chk1 for efficient viral infection. Interestingly, CHIKV infection was found to cause DNA damage and arrest cell cycle in G1 and G2 phases to facilitate viral infection. This information might facilitate to develop effective therapeutics for the control of the CHIKV infection in future.

microbiology↗

bioRxiv2021

Telmisartan restricts Chikungunya virus infection in vitro and in vivo through the AT1/ PPAR-γ/MAPKs pathways

Chikungunya virus (CHIKV) has re-emerged as a global public health threat. The inflammatory pathways of RAS and PPAR-{gamma} are usually involved in viral infections. Thus, Telmisartan (TM) with known capacity to block AT1 receptor and activate PPAR-{gamma}, was investigated against CHIKV. The anti-CHIKV effect of TM was investigated in vitro (Vero, RAW 264.7 cells and hPBMCs) and in vivo (C57BL/6 mice). TM was found to abrogate CHIKV infection efficiently (IC50 of 15.34-20.89{micro}M in the Vero and RAW 264.7 cells respectively). Viral RNA and proteins were reduced remarkably with the TM driven modulation of host m-TOR signaling. Additionally, TM interfered in the early and late stages of CHIKV life cycle with efficacy in both pre and post-treatment assay. Moreover, the agonist of AT1 receptor and antagonist of PPAR-{gamma} increased CHIKV infection suggesting TMs anti-viral potential by modulating host factors. Besides, reduced activation of all major MAPKs, NF-{kappa}B (p65) and cytokines by TM through the inflammatory axis supported the fact that the anti-CHIKV efficacy of TM is partly mediated through the AT1/PPAR-{gamma}/MAPKs pathways. Interestingly, at the human equivalent dose, TM abrogated CHIKV infection and inflammation significantly leading to reduced clinical score and complete survival of C57BL/6 mice. Additionally, TM reduced infection in hPBMC derived monocyte-macrophage populations in vitro. Hence, TM was found to reduce CHIKV infection by targeting both viral and host factors. Considering its safety and in vivo efficacy, it can be a suitable candidate in future for repurposing against CHIKV.

microbiology↗