Biology subjects

Jain, R.

Publications and source records attributed to Jain, R..

At least 37 records · Page 2Linked to original sources

bioRxiv2024

Multiple molecular links between the circadian clock and memory centers in honey bees

Time and memory are intimately linked: the capability to learn and recall varies over the day and humans and many animals can associate important events with the time of day. However, how the circadian clock and memory centers are connected is not well understood. We time-trained honey bee foragers and used RNA-sequencing and RNAscope imaging to analyze gene expression changes in focal populations of mushroom body neurons. Thus, we identified three candidate functional modules of time-memory: synchronized peak-level expression of memory-related genes during training time, anticipatory activation of transcription in pdfr-expressing neurons, and cry2 and per co-expressing neurons that might represent local clocks. The complex interactions between the clock and memory centers, which appear to be more similar to mammals than other insects, might have been facilitated to optimize social foraging in honey bees.

neuroscience↗

bioRxiv2024

Conditional c-MYC activation in catecholaminergic cells drives distinct neuroendocrine tumors: neuroblastoma vs somatostatinoma

The MYC proto-oncogenes (c-MYC, MYCN, MYCL) are among the most deregulated oncogenic drivers in human malignancies including high-risk neuroblastoma, 50% of which are MYCN-amplified. Genetically engineered mouse models (GEMMs) based on the MYCN transgene have greatly expanded the understanding of neuroblastoma biology and are powerful tools for testing new therapies. However, a lack of c-MYC-driven GEMMs has hampered the ability to better understand mechanisms of neuroblastoma oncogenesis and therapy development given that c-MYC is also an important driver of many high-risk neuroblastomas. In this study, we report two transgenic murine neuroendocrine models driven by conditional c-MYC induction in tyrosine hydroxylase (Th) and dopamine {beta}-hydroxylase (Dbh)-expressing cells. c-MYC induction in Th-expressing cells leads to a preponderance of Pdx1+ somatostatinomas, a type of pancreatic neuroendocrine tumor (PNET), resembling human somatostatinoma with highly expressed gene signatures of {delta} cells and potassium channels. In contrast, c-MYC induction in Dbh-expressing cells leads to onset of neuroblastomas, showing a better transforming capacity than MYCN in a comparable C57BL/6 genetic background. The c-MYC murine neuroblastoma tumors recapitulate the pathologic and genetic features of human neuroblastoma, express GD2, and respond to anti-GD2 immunotherapy. This model also responds to DFMO, an FDA-approved inhibitor targeting ODC1, which is a known MYC transcriptional target. Thus, establishing c-MYC-overexpressing GEMMs resulted in different but related tumor types depending on the targeted cell and provide useful tools for testing immunotherapies and targeted therapies for these diseases.

cancer biology↗

bioRxiv2024

A Machine Learning-based approach for Simultaneous Electrochemical Detection of Interfering Analytes

Electrochemical biosensors can be used to detect analytes of importance precisely. These sensors generate rapid and accurate electrical signals that reveal the presence and concentration of the targeted analyte. Detecting multiple analytes simultaneously with an electrochemical biosensor is advantageous. It provides cost and time efficiency, multiplexing capability, and flexibility, making it valuable in diverse applications such as medical diagnostics, environmental monitoring, and industrial processes. However, simultaneous detection of analytes may suffer from the problem of interference. The interference effect causes the signal of an analyte at a particular concentration to deviate from the expected one. We observe a similar effect in the simultaneous detection of Folic Acid and Uric Acid using a nanomaterial-based electrochemical sensor. To address this effect, we propose a machine learning (ML) approach. ML algorithms handle complex interactions by autonomously identifying patterns, dependencies, and nonlinear relationships within data, enabling it to make predictions and decisions in intricate and dynamic scenarios. Our approach can be generalised to any two analytes showing interference and would scale well to interference between multiple analytes. We test several regression algorithms and compare their performance to the standard calibration plot method. As compared to the standard method, our approach shows a 4.49 {micro}M decrease in concentration prediction error.

bioengineering↗

bioRxiv2024

Expression of Plasmodium Major Facilitator Superfamily Protein in Transporters-Delta Candida Identifies a Drug Transporter

AimTo assess the functional relevance of a putative Major Facilitator Superfamily (MFS) protein (PF3D7_0210300; "PfMFS_DT") as a drug transporter, using Candida glabrata for orthologous protein expression. MethodsCDS encoding PfMFS_DT was integrated into the genome of genetically engineered C. glabrata strain MSY8 via homologous recombination, followed by assessing its functional relevance as a drug transporter. Results and ConclusionThe modified C. glabrata strain exhibited plasma membrane localization of PfMFS_DT and characteristics of an MFS transporter, conferring resistance to antifungals, ketoconazole and itraconazole. The nanomolar inhibitory effects of the drugs on the intra-erythrocytic growth of P. falciparum highlight their antimalarial properties. This study proposes PfMFS_DT as a drug transporter, expanding the repertoire of the currently known antimalarial "resistome".

cell biology↗

bioRxiv2024

Microtubule forces drive nuclear damage in LMNA cardiomyopathy

Nuclear homeostasis requires a balance of forces between the cytoskeleton and nucleus. Mutations in the LMNA gene, which encodes the nuclear envelope proteins lamin A/C, disrupt this balance by weakening the nuclear lamina. This results in nuclear damage in contractile tissues and ultimately muscle disease. Intriguingly, disrupting the LINC complex that connects the cytoskeleton to the nucleus has emerged as a promising strategy to ameliorate LMNA-associated cardiomyopathy. Yet how LINC complex disruption protects the cardiomyocyte nucleus remains unclear. To address this question, we developed an assay to quantify the coupling of cardiomyocyte contraction to nuclear deformation and interrogated its dependence on the nuclear lamina and LINC complex. We found that, surprisingly, the LINC complex was mostly dispensable for transferring contractile strain to the nucleus, and that increased nuclear strain in lamin A/C-deficient cardiomyocytes was not rescued by LINC complex disruption. Instead, LINC complex disruption eliminated the cage of microtubules encircling the nucleus. Disrupting microtubules was sufficient to prevent nuclear damage and rescue cardiac function induced by lamin A/C deficiency. We computationally simulated the stress fields surrounding cardiomyocyte nuclei and show how microtubule forces generate local vulnerabilities that damage lamin A/C-deficient nuclei. Our work pinpoints localized, microtubule-dependent force transmission to the nucleus as a pathological driver and therapeutic target for LMNA- cardiomyopathy. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=131 SRC="FIGDIR/small/579774v5_ufig1.gif" ALT="Figure 1"> View larger version (52K): org.highwire.dtl.DTLVardef@1443daeorg.highwire.dtl.DTLVardef@12d7a8borg.highwire.dtl.DTLVardef@c85900org.highwire.dtl.DTLVardef@14b3c89_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗

bioRxiv2024

Tyrosine-sulfated peptide hormone induces flavonol biosynthesis to control elongation and differentiation in Arabidopsis primary root.

In Arabidopsis roots, growth initiation and cessation are organized into distinct zones. How regulatory mechanisms are integrated to coordinate these processes and maintain proper growth progression over time is not well understood. Here, we demonstrate that the peptide hormone PLANT PEPTIDE CONTAINING SULFATED TYROSINE 1 (PSY1) promotes root growth by controlling cell elongation. Higher levels of PSY1 lead to longer differentiated cells with a shootward displacement of characteristics common to mature cells. PSY1 activates genes involved in the biosynthesis of flavonols, a group of plant-specific secondary metabolites. Using genetic and chemical approaches, we show that flavonols are required for PSY1 function. Flavonol accumulation downstream of PSY1 occurs in the differentiation zone, where PSY1 also reduces auxin and reactive oxygen species (ROS) activity. These findings support a model where PSY1 signals the developmental-specific accumulation of secondary metabolites to regulate the extent of cell elongation and the overall progression to maturation. Teaser PSY1-induced flavonol biosynthesis in Arabidopsis roots modulates the distance from the root tip at which cell elongation ceases.

plant biology↗

bioRxiv2024

ACAD10 and ACAD11 enable mammalian 4-hydroxy acid lipid catabolism

Fatty acid {beta}-oxidation (FAO) is a central catabolic pathway with broad implications for organismal health. However, various fatty acids are largely incompatible with standard FAO machinery until they are modified by other enzymes. Included among these are the 4-hydroxy acids (4-HAs)--fatty acids hydroxylated at the 4 ({gamma}) position--which can be provided from dietary intake, lipid peroxidation, and certain drugs of abuse. Here, we reveal that two atypical and poorly characterized acyl-CoA dehydrogenases (ACADs), ACAD10 and ACAD11, drive 4-HA catabolism in mice. Unlike other ACADs, ACAD10 and ACAD11 feature kinase domains N-terminal to their ACAD domains that phosphorylate the 4-OH position as a requisite step in the conversion of 4-hydroxyacyl-CoAs into 2-enoyl-CoAs--conventional FAO intermediates. Our ACAD11 cryo-EM structure and molecular modeling reveal a unique binding pocket capable of accommodating this phosphorylated intermediate. We further show that ACAD10 is mitochondrial and necessary for catabolizing shorter-chain 4-HAs, whereas ACAD11 is peroxisomal and enables longer-chain 4-HA catabolism. Mice lacking ACAD11 accumulate 4-HAs in their plasma while comparable 3- and 5-hydroxy acids remain unchanged. Collectively, this work defines ACAD10 and ACAD11 as the primary gatekeepers of mammalian 4-HA catabolism and sets the stage for broader investigations into the ramifications of aberrant 4-HA metabolism in human health and disease.

biochemistry↗

bioRxiv2023

Fatty Acid Metabolism and The Oxidative Stress Response Support Bacterial Predation

Despite growing awareness of their importance in soil ecology, the genetic and physiological traits of bacterial predators are still relatively poorly understood. In the course of a Myxococcus xanthus predator evolution experiment, we discovered a class of genotypes leading to enhanced predation against diverse species. RNA-seq analysis demonstrated that this phenotype is linked to the constitutive activation of a predation-specific program. Functional analysis of the mutations accumulated across the evolutionary time in a two- component system and Acyl-CoA-manipulating enzymes revealed the critical roles of fatty acid metabolism and antioxidant gene induction. The former likely adapts the predator to metabolites derived from the prey while the latter protects predatory cells from reactive oxygen species (ROS) generated by prey cells under stress and released upon lysis during predation. These findings reveal interesting parallels between bacterial predator-prey dynamics and pathogen-host cell interactions. Significance StatementThis study illuminates the largely unexplored genetic and metabolic strategies used by bacterial predators in soil ecosystems. Through experimental evolution in Myxococcus xanthus, we discovered that more efficient predators accumulate mutations that activate a genetic program for predation. This program simultaneously triggers a metabolic shift favoring fatty acid degradation for energy production and upregulates antioxidant gene expression, enhancing protection against reactive oxygen species generated during prey cell lysis. This adaptive mechanism proves advantageous across a wide range of prey species, suggesting that metabolic adaptation plays a crucial role in the evolutionary trajectory of bacterial predators within their natural ecological niche.

microbiology↗

bioRxiv2023

A novel method of testing the antimicrobial potentials of Exiguobacterium aurantiacum, Lysinibacillus boronitolerans and Bacillus megaterium

Microorganisms can be an effective source for antimicrobial compounds including peptides that provide an evolutionary advantage to them in specific niches. Prior studies have noted the antimicrobial properties of Exiguobacterium aurantiacum, Lysinibacillus boronitolerans and Bacillus megaterium but they used time- and resource-intensive procedures to prepare the extracts (2, 10). We wanted to explore a more cost-effective, time-effective and simpler method of testing the antimicrobial potential of bacterial extracts. Our extraction protocol is a one-step incubation of the organism in the solvent overnight, followed by a standard well diffusion based assay to test its antimicrobial effect. We tested this method with three cultures isolated from the premises of Mumbai railway stations: E. aurantiacum, L. boronitolerans and Bacillus megaterium. These extracts were tested against human pathogens Staphylococcus aureus and Enterococcus faecalis. E. aurantiacum, L. boronitolerans and B. megaterium inhibited S. aureus by 9.17 {+/-} 0.42, 9.25 {+/-} 0.48 and 10.50 {+/-} 1.5 mm, respectively, and E. faecalis by 15.79 {+/-} 2.25, 14.21 {+/-} 0.88 and 17.5 {+/-} 2.89 mm, respectively. This approach is therefore suggested to be effective for screening the antimicrobial activity of these bacteria.

microbiology↗

bioRxiv2023

Modulation of hepatic transcription factor EB activity during cold exposure uncovers direct regulation of bis(monoacylglycerol)phosphate lipids by Pla2g15

Cold exposure is a selective environmental stress that elicits a rapid metabolic shift to maintain energy homeostasis. In response to cold exposure, the liver rewires the metabolic state shifting from glucose to lipid catabolism. By probing the liver lipids in cold exposure, we observed that the lysosomal bis(monoacylglycero)phosphate (BMP) lipids were rapidly increased during cold exposure. BMP lipid changes occurred independently of lysosomal abundance but were dependent on the lysosomal transcriptional regulator transcription factor EB (TFEB). Knockdown of TFEB in hepatocytes decreased BMP lipid levels and led to cold intolerance in mice. We assessed TFEB binding sites of lysosomal genes and determined that the phospholipase Pla2g15 regulates BMP lipid catabolism. Knockdown of Pla2g15 in mice increased BMP lipid levels, ablated the cold-induced rise, and improved cold tolerance. Knockout of Pla2g15 in mice and hepatocytes led to increased BMP lipid levels, that were decreased with re-expression of Pla2g15. Mutation of the catalytic site of Pla2g15 ablated the BMP lipid breakdown. Together, our studies uncover TFEB regulation of BMP lipids through Pla2g15 catabolism.

biochemistry↗

bioRxiv2023

Membrane Bound O-Acyltransferase 7 (MBOAT7) Shapes Lysosomal Lipid Homeostasis and Function to Control Alcohol-Associated Liver Injury

Several recent genome-wide association studies (GWAS) have identified single nucleotide polymorphism (SNPs) near the gene encoding membrane-bound O-acyltransferase 7 (MBOAT7) that is associated with advanced liver diseases. In fact, a common MBOAT7 variant (rs641738), which is associated with reduced MBOAT7 expression, confers increased susceptibility to non-alcoholic fatty liver disease (NAFLD), alcohol-associated liver disease (ALD), and liver fibrosis in those chronically infected with hepatitis viruses B and C. The MBOAT7 gene encodes a lysophosphatidylinositol (LPI) acyltransferase enzyme that produces the most abundant form of phosphatidylinositol 38:4 (PI 18:0/20:4). Although these recent genetic studies clearly implicate MBOAT7 function in liver disease progression, the mechanism(s) by which MBOAT7-driven LPI acylation regulates liver disease is currently unknown. Previously we showed that antisense oligonucleotide (ASO)-mediated knockdown of Mboat7 promoted non-alcoholic fatty liver disease (NAFLD) in mice (Helsley et al., 2019). Here, we provide mechanistic insights into how MBOAT7 loss of function promotes alcohol-associated liver disease (ALD). In agreement with GWAS studies, we find that circulating levels of metabolic product of MBOAT7 (PI 38:4) are significantly reduced in heavy drinkers compared to age-matched healthy controls. Hepatocyte specific genetic deletion (Mboat7HSKO), but not myeloid-specific deletion (Mboat7MSKO), of Mboat7 in mice results in enhanced ethanol-induced hepatic steatosis and high concentrations of plasma alanine aminotransferase (ALT). Given MBOAT7 is a lipid metabolic enzyme, we performed comprehensive lipidomic profiling of the liver and identified a striking reorganization of the hepatic lipidome upon ethanol feeding in Mboat7HSKO mice. Specifically, we observed large increases in the levels of endosomal/lysosomal lipids including bis(monoacylglycero)phosphates (BMP) and phosphatidylglycerols (PGs) in ethanol-exposed Mboat7HSKO mice. In parallel, ethanol-fed Mboat7HSKO mice exhibited marked dysregulation of autophagic flux and lysosomal biogenesis when exposed to ethanol. This was associated with impaired transcription factor EB (TFEB)-mediated lysosomal biogenesis and accumulation of autophagosomes. Collectively, this works provides new molecular insights into how genetic variation in MBOAT7 impacts ALD progression in humans and mice. This work is the first to causally link MBOAT7 loss of function in hepatocytes, but not myeloid cells, to ethanol-induced liver injury via dysregulation of lysosomal biogenesis and autophagic flux.

cell biology↗

bioRxiv2023

Mutant analysis of Kcng4b reveals how the different functional states of the voltage-gated potassium channel regulate ear development

The voltage gated (Kv) slow-inactivating delayed rectifier channel regulates the development of hollow organs of the zebrafish. The functional tetramer consists of an electrically active subunit (Kcnb1, Kv2.1) and a modulatory silent subunit (Kcng4b, Kv6.4). The two mutations in zebrafish kcng4b - kcng4b-C1 and kcng4b-C2 (Gasanov et al., 2021) - have been studied during ear development using electrophysiology, developmental biology and in silico structural modelling. kcng4b-C1 mutation causes a C-terminal truncation characterized by mild Kcng4b loss-of-function (LOF) manifested by failure of kinocilia to extend and formation of ectopic otoliths. In contrast, the kcng4b-C2-/- mutation causes the C-terminal domain to elongate and the ectopic seventh transmembrane (TM) domain to form, converting the intracellular C-terminus to an extracellular one. Kcng4b-C2 acts as a Kcng4b gain-of-function (GOF) allele. Otoliths fail to develop and kinocilia are reduced in kcng4b-C2-/-. These results show that different mutations of the silent subunit Kcng4 can affect the activity of the Kv channel and cause a wide range of developmental defects.

developmental biology↗

bioRxiv2023

Extensive profiling of transcription factors in postmortem brains defines genomic occupancy in disease-relevant cell types and links TF activities to neuropsychiatric disorders

Transcription factors (TFs) orchestrate gene expression programs crucial for cell physiology, but our knowledge of their function in the brain is limited. Using bulk tissues and sorted nuclei from multiple human post-mortem brain regions, we generated a multi-omic resource (1121 total experiments) that includes binding maps for more than 100 TFs. We demonstrate improved measurements of TF activity, including motif recognition and gene expression modeling, upon identification and removal of regions of high TF occupancy. Further, we find that predictive TF binding models demonstrate a bias for these high occupancy sites. Neuronal TFs SATB2 and TBR1 bind unique regions depleted for such sites and promote neuronal gene expression. Several TFs, including TBR1 and PKNOX1, are enriched for risk variants associated with neuropsychiatric disorders, predominantly in neurons. These data are a powerful resource for future studies seeking to understand the role of TFs in epigenetic regulation in the human brain.

genomics↗

bioRxiv2023

HNF4a regulates acyl chain remodeling and ether lipid accumulation in hepatic steatosis

Hepatocyte nuclear factor 4 (HNF4) is an established transcriptional master regulator of differentiation, maintenance, and metabolism. Polymorphisms in HNF4 are linked to several diseases in humans including diabetes and nonalcoholic fatty liver disease (NAFLD). Identifying novel regulation of lipid metabolism by HNF4 would inform on NAFLD development and progression. We directly assessed HNF4 activity through chromatin immunoprecipitation (ChIP)-sequencing and integration of untargeted lipidomics. Direct regulation by HNF4 can be difficult to assess due to the role of HNF4 in liver homeostasis; to rapidly disrupt activity, mice were exposed to cold stress which induces hepatic steatosis in several hours. Cold exposure shifted HNF4 activity with differential genome occupancy of more than 50% of HNF4 binding sites. Focusing on HNF4 binding to promoter with active transcription determined that HNF4 directly regulates fatty acid desaturation, ether lipid synthesis, and peroxisomal biogenesis in response to cold exposure. Integration of lipidomics found that cold exposure increases the very long chain polyunsaturated fatty acid composition of the hepatic lipid pool, including ether lipids, in an HNF4 dependent manner. Because portions of ether lipid synthesis are in the peroxisome and peroxisomal biogenesis is directly HNF4 regulated, we analyzed peroxisomal abundance and found increases with cold exposure that are ablated with loss of HNF4. This peroxisomal regulation was independent of PPAR-- a known regulator of peroxisomes and lipid metabolism--since loss of HNF4 was not rescued by PPAR overexpression. These data determined that regulation of hepatic steatosis by HNF4 is more complex than triglyceride accumulation and includes acyl chain modifications, ether lipid synthesis, and peroxisomal oxidation.

molecular biology↗

bioRxiv2023

Endodermal BRD4 mediates epithelial-mesenchymal crosstalk during lung development

Lung morphogenesis relies on diverse cell intrinsic and extrinsic mechanisms to ensure proper cellular differentiation and compartmentalization. Using genetic mouse models, tissue explants, and transcriptomic analysis, we demonstrate that the epigenetic reader Bromodomain Containing Protein 4 (BRD4) is required for lung morphogenesis and perinatal survival. Endodermal BRD4 deletion impairs epithelial-mesenchymal crosstalk, leading to disrupted proximal-distal patterning and branching morphogenesis. These early defects result in dilated airways and the formation of cystic distal airway structures, containing both airway and alveolar features. Moreover, BRD4 deficient lungs exhibit abnormal airway and alveolar epithelial cell lineage allocation and differentiation. Restoration of SHH signaling partially rescues defects due to loss of BRD4, suggesting a role for BRD4 in regulating the SHH-FGF signaling axis. Together, these data identify the essential role of Brd4 in lung development to ensure proper intercellular crosstalk to enable proper lineage specification, identity, and maturation.

developmental biology↗

bioRxiv2023

A multiadjuvant polysaccharide-amino acid-lipid (PAL) subunit nanovaccine generates robust systemic and lung-specific mucosal immune responses against SARS-CoV-2 in mice

Existing parenteral SARS-CoV-2 vaccines produce only limited mucosal responses, which are essential for reducing transmission and achieving sterilizing immunity. Appropriately designed mucosal boosters could overcome the shortcomings of parenteral vaccines and enhance pre- existing systemic immunity. Here we present a new protein subunit nanovaccine using multiadjuvanted (e.g. RIG-I: PUUC, TLR9: CpG) polysaccharide-amino acid-lipid nanoparticles (PAL-NPs) that can be delivered both intramuscularly (IM) and intranasally (IN) to generate balanced mucosal-systemic SARS-CoV-2 immunity. Mice receiving IM-Prime PUUC+CpG PAL- NPs, followed by an IN-Boost, developed high levels of IgA, IgG, and cellular immunity in the lung, and showed robust systemic humoral immunity. Interestingly, as a purely intranasal vaccine (IN-Prime/IN-Boost), PUUC+CpG PAL-NPs induced stronger lung-specific T cell immunity than IM-Prime/IN-Boost, and a comparable IgA and neutralizing antibodies, although with a lower systemic antibody response, indicating that a fully mucosal delivery route for SARS-CoV-2 vaccination may also be feasible. Our data suggest that PUUC+CpG PAL-NP subunit vaccine is a promising candidate for generating SARS-CoV-2 specific mucosal immunity.

bioengineering↗

bioRxiv2023

memo-eQTL: DNA methylation modulated genetic variant effect on gene transcriptional regulation

Expression quantitative trait locus (eQTL) analysis has become an important tool in understanding the link between genetic variants and gene expression, ultimately helping to bridge the gap between risk SNPs and associated diseases. Recently, we identified and validated a specific case where the methylation of a CpG site can affect the relationship between the genetic variant and gene expression. To systematically evaluate this regulatory mechanism, we developed an extended eQTL mapping method named DNA methylation modulated eQTL (memo-eQTL). We performed memo-eQTL mapping in 128 normal prostate samples and discovered 1,731 memo-eQTLs, a vast majority of which have not been reported as eQTLs. We found that the methylation of the memo-eQTL CpG sites can either enhance or insulate the interaction between SNP and Gene expression by altering CTCF-based chromatin 3D structure. This study demonstrated the prevalence of memo-eQTLs, which can enable the identification of novel causal genes for traits or diseases associated with genetic variations.

bioinformatics↗

bioRxiv2023

Tackling emerging artemisinin resistance by modulating the defensive oxido-reductive mechanism of human malaria parasite by repurposing nitrofurantoin

Oxidative stress mediated cell death has remained the prime parasiticidal mechanism of front line anti-malarial, artemisinin (ART). The emergence of resistant Plasmodium parasites characterized by oxidative stress management due to impaired activation of ART as well as enhanced ROS detoxification has decreased its clinical efficacy. This gap can be filled by development of alternative chemotherapeutic agents to combat resistance defense mechanism. Interestingly, repositioning of clinically approved drugs presents an emerging approach for expediting anti-malarial drug development and resistance management. Herein, we evaluated the anti-malarial potential of Nitrofurantoin (NTF), a clinically used antibacterial drug, against intra-erythrocytic stages of ART-sensitive (Pf3D7) and resistant (PfKelch13R539T) strains of Plasmodium falciparum (Pf), alone and in combination with ART. NTF exhibited growth inhibitory effect at sub micro molar concentration by arresting parasite growth at trophozoite stage. It also inhibited the survival of resistant parasites as revealed by ring survival assay. Concomitantly, in vitro combination assay revealed synergistic association of NTF with ART. NTF was found to enhance the reactive oxygen and nitrogen species as well as induced mitochondrial membrane depolarization in parasite. Furthermore, we found that exposure of parasites to NTF disrupted their redox balance by impeding Pf Glutathione Reductase activity, which manifests in enhanced oxidative stress, inducing parasite death. In vivo administration of NTF, alone and in combination with ART in P. berghei ANKA infected mice blocked parasite multiplication and enhanced mean survival time. Overall, our results indicate NTF as a promising repurposable drug with therapeutic potential against drug sensitive as well as resistant parasites.

pharmacology and toxicology↗