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1.
Biochim Biophys Acta Mol Basis Dis ; 1870(7): 167444, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39074627

ABSTRACT

The glucose-6-phosphate dehydrogenase (G6PD) deficiency is X-linked and is the most common enzymatic deficiency disorder globally. It is a crucial enzyme for the pentose phosphate pathway and produces NADPH, which plays a vital role in regulating the oxidative stress of many cell types. The deficiency of G6PD primarily causes hemolytic anemia under oxidative stress triggered by food, drugs, or infection. G6PD-deficient patients infected with SARS-CoV-2 showed an increase in hemolysis and thrombosis. Patients also exhibited prolonged COVID-19 symptoms, ventilation support, neurological impacts, and high mortality. However, the mechanism of COVID-19 severity in G6PD deficient patients and its neurological manifestation is still ambiguous. Here, using a CRISPR-edited G6PD deficient human microglia cell culture model, we observed a significant reduction in NADPH level and an increase in basal reactive oxygen species (ROS) in microglia. Interestingly, the deficiency of the G6PD-NAPDH axis impairs induced nitric oxide synthase (iNOS) mediated nitric oxide (NO) production, which plays a fundamental role in inhibiting viral replication. Surprisingly, we also observed that the deficiency of the G6PD-NADPH axis reduced lysosomal acidification and free radical production, further abrogating the lysosomal clearance of viral particles. Thus, impairment of NO production, lysosomal functions, and redox dysregulation in G6PD deficient microglia altered innate immune response, promoting the severity of SARS-CoV-2 pathogenesis.


Subject(s)
COVID-19 , Glucosephosphate Dehydrogenase Deficiency , Glucosephosphate Dehydrogenase , Lysosomes , Microglia , Nitric Oxide Synthase Type II , Phagocytosis , SARS-CoV-2 , Humans , Microglia/metabolism , Microglia/pathology , Glucosephosphate Dehydrogenase Deficiency/metabolism , Glucosephosphate Dehydrogenase Deficiency/pathology , Glucosephosphate Dehydrogenase Deficiency/genetics , COVID-19/metabolism , COVID-19/pathology , COVID-19/virology , COVID-19/immunology , Lysosomes/metabolism , Nitric Oxide Synthase Type II/metabolism , Nitric Oxide Synthase Type II/genetics , Glucosephosphate Dehydrogenase/metabolism , Glucosephosphate Dehydrogenase/genetics , Reactive Oxygen Species/metabolism , NADP/metabolism , Nitric Oxide/metabolism , Oxidative Stress
2.
Proteomics Clin Appl ; : e202300115, 2024 Jul 31.
Article in English | MEDLINE | ID: mdl-39082488

ABSTRACT

PURPOSE: Merozoites are the only extracellular form of blood stage parasites, making it a worthwhile target. Multiple invasins that are stored in the merozoite apical organelles, are secreted just prior to invasion, and mediates its interaction with RBC. A comprehensive identification of all these secreted invasins is lacking and this study addresses that gap. EXPERIMENTAL DESIGN: Pf3D7 merozoites were enriched and triggered to discharge apical organelle contents by exposure to ionic conditions mimicking that of blood plasma. The secreted proteins were separated from cellular contents and both the fractions were subjected to proteomic analysis. Also, the identified secreted proteins were subjected to GO, PPI network analysis, and AI-based in silico approach to understand their vaccine candidacy. RESULTS: A total of 63 proteins were identified in the secretory fraction with membrane and apical organellar localization. This includes various MSPs, micronemal EBAs and rhoptry bulb proteins, which play a crucial role in initial and late merozoite attachment, and majority of them qualified as vaccine candidates. CONCLUSION AND CLINICAL RELEVANCE: We, for the first time, report the secretory repertoire of merozoite and its status for vaccine candidacy. This information can be utilized to develop better invasion blocking multisubunit vaccines, comprising of immunological epitopes from several secreted invasins.

3.
J Biol Chem ; 300(8): 107496, 2024 Jun 24.
Article in English | MEDLINE | ID: mdl-38925325

ABSTRACT

Emerging Artemisinin (ART) resistance in Plasmodium falciparum (Pf) poses challenges for the discovery of novel drugs to tackle ART-resistant parasites. Concentrated efforts toward the ART resistance mechanism indicated a strong molecular link of ART resistance with upregulated expression of unfolded protein response pathways involving Prefoldins (PFDs). However, a complete characterization of PFDs as molecular players taking part in ART resistance mechanism, and discovery of small molecule inhibitors to block this process have not been identified to date. Here, we functionally characterized all Pf Prefoldin subunits (PFD1-6) and established a causative role played by PFDs in ART resistance by demonstrating their expression in intra-erythrocytic parasites along with their interactions with Kelch13 protein through immunoprecipitation coupled MS/MS analysis. Systematic biophysical interaction analysis between all subunits of PFDs revealed their potential to form a complex. The role of PFDs in ART resistance was confirmed in orthologous yeast PFD6 mutants, where PfPFD6 expression in yeast mutants reverted phenotype to ART resistance. We identified an FDA-approved drug "Biperiden" that restricts the formation of Prefoldin complex and inhibits its interaction with its key parasite protein substrates, MSP-1 and α-tubulin-I. Moreover, Biperiden treatment inhibits the parasite growth in ART-sensitive Pf3D7 and resistant Pf3D7k13R539T strains. Ring survival assays that are clinically relevant to analyze ART resistance in Pf3D7k13R539T parasites demonstrate the potency of BPD to inhibit the growth of survivor parasites. Overall, our study provides the first evidence of the role of PfPFDs in ART resistance mechanisms and opens new avenues for the management of resistant parasites.

4.
Cureus ; 16(4): e58502, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38765429

ABSTRACT

Osteoarthritis (OA) and diabetes mellitus (DM) have long-term deleterious chronic effects and are among the most prevalent chronic disorders. DM and its associated factors, such as hyperglycemia, have a significant contribution to the pathophysiology of OA, particularly in post-menopausal women. Women who have uncontrolled diabetes (DM) are more prone to develop osteoarthritis (OA), which may be exacerbated by poor glycemic control. Furthermore, this category of female patients with DM has an increased risk of developing fractures, even in those with initially normal bone density scores, further illustrating the correlation between DM and bone health. Additionally, multiple risk factors, including obesity, metabolic syndrome, hypertension, estrogen-based hormone therapy, and hyperuricemia, in menopausal women can lead to the development and exacerbation of OA. It is discovered that these variables have a direct or indirect impact, frequently causing inflammation and hormonal changes, which contribute to the intricate interaction between DM and OA. The management of OA and DM in women thus calls for a multi-faceted management plan including glycemic control, weight control, exercise, and specialized pain management methods catering to the specific requirements of the patients. Regularly screening for OA should be implemented for menopausal women with DM and utmost care should be provided by healthcare professionals. Regular monitoring of joint health and early management, encouraging interdisciplinary cooperation, putting preventative measures into place, and creating individualized treatment programs are essential. A thorough understanding of the link between DM and OA will ultimately lead to improved health outcomes and a better future for these individuals.

5.
iScience ; 27(6): 109918, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38812541

ABSTRACT

Malaria parasite invasion to host erythrocytes is mediated by multiple interactions between merozoite ligands and erythrocyte receptors that contribute toward the development of disease pathology. Here, we report a novel antigen Plasmodium prohibitin "PfPHB2" and identify its cognate partner "Hsp70A1A" in host erythrocyte that plays a crucial role in mediating host-parasite interaction during merozoite invasion. Using small interfering RNA (siRNA)- and glucosamine-6-phosphate riboswitch (glmS) ribozyme-mediated approach, we show that loss of Hsp70A1A in red blood cells (RBCs) or PfPHB2 in infected red blood cells (iRBCs), respectively, inhibit PfPHB2-Hsp70A1A interaction leading to invasion inhibition. Antibodies targeting PfPHB2 and monoclonal antibody therapeutics against Hsp70A1A efficiently block parasite invasion. Recombinant PfPHB2 binds to RBCs which is inhibited by anti-PfPHB2 antibody and monoclonal antibody against Hsp70A1A. The validation of PfPHB2 to serve as antigen is further supported by detection of anti-PfPHB2 antibody in patient sera. Overall, this study proposes PfPHB2 as vaccine candidate and highlights the use of monoclonal antibody therapeutics for future malaria treatment.

7.
ACS Infect Dis ; 10(6): 2074-2088, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38717971

ABSTRACT

Palmitoylation is an essential post-translational modification in Leishmania donovani, catalyzed by enzymes called palmitoyl acyl transferases (PATs) and has an essential role in virulence. Due to the toxicity and promiscuity of known PAT inhibitors, identification of new molecules is needed. Herein, we identified a specific novel de novo peptide inhibitor, PS1, against the PAT6 Leishmania donovani palmitoyl acyl transferase (LdPAT6). To demonstrate specific inhibition of LdPAT6 by PS1, we employed a bacterial orthologue system and metabolic labeling-coupled click chemistry where both LdPAT6 and PS1 were coexpressed and displayed palmitoylation suppression. Furthermore, strong binding of the LdPAT6-DHHC domain with PS1 was observed through analysis using microscale thermophoresis, ELISA, and dot blot assay. PS1 specific to LdPAT6 showed significant growth inhibition in promastigotes and amastigotes by expressing low cytokines levels and invasion. This study reveals discovery of a novel de novo peptide against LdPAT6-DHHC which has potential to block survivability and infectivity of L. donovani.


Subject(s)
Acyltransferases , Leishmania donovani , Peptides , Leishmania donovani/enzymology , Leishmania donovani/drug effects , Leishmania donovani/genetics , Acyltransferases/metabolism , Acyltransferases/genetics , Acyltransferases/antagonists & inhibitors , Acyltransferases/chemistry , Peptides/pharmacology , Peptides/chemistry , Animals , Protozoan Proteins/metabolism , Protozoan Proteins/genetics , Protozoan Proteins/antagonists & inhibitors , Protozoan Proteins/chemistry , Lipoylation , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Mice , Antiprotozoal Agents/pharmacology , Antiprotozoal Agents/chemistry , Leishmaniasis, Visceral/parasitology
8.
iScience ; 27(5): 109574, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38646175

ABSTRACT

The chemical understanding of biological processes provides not only a deeper insight but also a solution to abnormal biological functioning. Protein degradation, a natural biological process for debris removal in the cell, has been studied for years. The recent finding that natural degradation pathways can be utilized for therapeutic purposes is a paradigm shift in the drug discovery approach. Methods such as Proteolysis Targeting Chimera (PROTAC), lysosomal targeting chimera, hydrophobic tagging, AUtophagy TArgeting Chimera, AUTOphagy TArgeting Chimera and several other variants of these methods have made a considerable impact on the way of drug design. Few selected examples testify that a huge wave of change is on the way. The drug design based on the targeted protein degradation is a powerful tool in our arsenal. More molecules will be invented that will uncover the hidden secrets of biological functioning and provide enduring solutions to several unmet medical needs.

9.
Int J Biol Macromol ; 265(Pt 1): 130420, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38460641

ABSTRACT

Proteolytic activity constitutes a fundamental process essential for the survival of the malaria parasite and is thus highly regulated. Falstatin, a protease inhibitor of Plasmodium falciparum, tightly regulates the activity of cysteine hemoglobinases, falcipain-2 and 3 (FP2, FP3), by inhibiting FP2 through a single surface exposed loop. However, the multimeric nature of falstatin and its interaction with FP2 remained unexplored. Here we report that the N-terminal falstatin region is highly disordered, and needs chaperone activity (heat-shock protein 70, HSP70) for its folding. Protein-protein interaction assays showed a significant interaction between falstatin and HSP70. Further, characterization of the falstatin multimer through a series of biophysical techniques identified the formation of a falstatin decamer, which was extremely thermostable. Computational analysis of the falstatin decamer showed the presence of five falstatin dimers, with each dimer aligned in a head-to-tail orientation. Further, the falstatin C-terminal region was revealed to be primarily involved in the oligomerization process. Stoichiometric analysis of the FP2-falstatin multimer showed the formation of a heterooligomeric complex in a 1:1 ratio, with the participation of ten subunits of each protein. Taken together, our results report a novel protease-inhibitor complex and strengthens our understanding of the regulatory mechanisms of major plasmodium hemoglobinases.


Subject(s)
Cysteine Endopeptidases , Plasmodium falciparum , Protein Folding
10.
Environ Geochem Health ; 46(4): 130, 2024 Mar 14.
Article in English | MEDLINE | ID: mdl-38483703

ABSTRACT

River Mahi drains through semi-arid regions (Western India) and is a major Arabian Sea draining river. As the principal surface water source, its water quality is important to the regional population. Therefore, the river water was sampled extensively (n = 64, 16 locations, 4 seasons and 2 years) and analyzed for 11 trace elements (TEs; Sr, V, Cu, Ni, Zn, Cd, Ba, Cr, Mn, Fe, and Co). Machine learning (ML) and multivariate statistical analysis (MVSA) were applied to investigate their possible sources, spatial-temporal-annual variations, evaluate multiple water quality parameters [heavy metal pollution index (HPI), heavy metal evaluation index (HEI)], and health indices [hazard quotient (HQ), and hazard index (THI)] associated with TEs. TE levels were higher than their corresponding world average values in 100% (Sr, V and Zn), 78%(Cu), 41%(Ni), 27%(Cr), 9%(Cd), 8%(Ba), 8%(Co), 6%(Fe), and 0%(Mn), of the samples. Three principal components (PCs) accounted for 74.5% of the TE variance: PC-1 (Fe, Co, Mn and Cu) and PC-2 (Sr and Ba) are contributed from geogenic sources, while PC-3 (Cr, Ni and Zn) are derived from geogenic and anthropogenic sources. HPI, HEI, HQ and THI all indicate that water quality is good for domestic purposes and poses little hazard. ML identified Random forest as the most suitable model for predicting HEI class (accuracy: 92%, recall: 92% and precision: 94%). Even with a limited dataset, the study underscores the potential application of ML to predictive classification modeling.


Subject(s)
Metals, Heavy , Trace Elements , Water Pollutants, Chemical , Environmental Monitoring , Water Pollutants, Chemical/analysis , Trace Elements/analysis , Rivers , Cadmium/analysis , Water Quality , Metals, Heavy/analysis , Risk Assessment
11.
Nat Commun ; 15(1): 1794, 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38413594

ABSTRACT

Ex vivo cellular system that accurately replicates sickle cell disease and ß-thalassemia characteristics is a highly sought-after goal in the field of erythroid biology. In this study, we present the generation of erythroid progenitor lines with sickle cell disease and ß-thalassemia mutation using CRISPR/Cas9. The disease cellular models exhibit similar differentiation profiles, globin expression and proteome dynamics as patient-derived hematopoietic stem/progenitor cells. Additionally, these cellular models recapitulate pathological conditions associated with both the diseases. Hydroxyurea and pomalidomide treatment enhanced fetal hemoglobin levels. Notably, we introduce a therapeutic strategy for the above diseases by recapitulating the HPFH3 genotype, which reactivates fetal hemoglobin levels and rescues the disease phenotypes, thus making these lines a valuable platform for studying and developing new therapeutic strategies. Altogether, we demonstrate our disease cellular systems are physiologically relevant and could prove to be indispensable tools for disease modeling, drug screenings and cell and gene therapy-based applications.


Subject(s)
Anemia, Sickle Cell , beta-Thalassemia , Humans , beta-Thalassemia/genetics , beta-Thalassemia/therapy , Fetal Hemoglobin/genetics , Fetal Hemoglobin/metabolism , Anemia, Sickle Cell/drug therapy , Anemia, Sickle Cell/genetics , Hematopoietic Stem Cells/metabolism , Genotype , CRISPR-Cas Systems
12.
Heliyon ; 10(3): e25077, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38327451

ABSTRACT

The rapid emergence of resistance to existing frontline antimalarial drugs emphasizes a need for the development of target-oriented molecules with novel modes of action. Given the importance of a plant-like Calcium-Dependent Protein Kinase 1 (PfCDPK1) as a stand-alone multistage signalling regulator of P. falciparum, we designed and synthesized 7-chloroquinoline-indole-chalcones tethered with a triazole (CQTrICh-analogs 7 (a-s) and 9) directed towards PfCDPK1. This was accomplished by reacting substituted 1-phenyl-3-(1-(prop-2-yn-1-yl)-1H-indol-3-yl) prop-2-en-1-one and 1-(prop-2-yn-1-yl)-1H-indole-3-carbaldehyde with 4-azido-7-chloroquinoline, respectively via a 'click' reaction. The selected CQTrICh-analogs: 7l and 7r inhibited the growth of chloroquine-sensitive 3D7 strain and -resistant RKL-9 isolate of Plasmodium falciparum, with IC50 values of 2.4 µM & 1.8 µM (7l), and 3.5 µM & 2.7 µM (7r), respectively, and showed no apparent hemolytic activity and cytotoxicity in mammalian cells. Intra-erythrocytic progression studies revealed that the active hybrids: 7l and 7r are effective against the mature stages of the parasite. 7l and 7r were found to stably interact with the catalytically active ATP-binding pocket of PfCDPK1 via energetically favourable H-bonds. The interaction was confirmed in vitro by microscale thermophoresis and kinase assays, which demonstrated that the active hybrids interact with PfCDPK1 and inhibit its kinase activity which is presumably responsible for the parasite growth inhibition. Interestingly, 7l and 7r showed no inhibitory effect on the human kinases, indicating their selectivity for the parasite kinase. We report the antiplasmodial potential of novel kinase-targeting bio-conjugates, a step towards developing pan-kinase inhibitors which is a prerequisite for multistage anti-malarial protection.

13.
Future Microbiol ; 19: 33-49, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37830931

ABSTRACT

Aim: Leishmaniasis is characterized by a spectrum of diseases with two main clinical forms, cutaneous and visceral, caused by Leishmania tropica and Leishmania donovani, respectively. Studying Leishmania's interaction with the epithelial barrier at the initial site of a bite is crucial to understanding the establishment of the disease. Materials & methods: To discern parasite-host epithelial interaction, we developed in vitro cellular models involving co-cultures of Leishmania and MDCK epithelial cells. Results: Both L. donovani-MDCK and L. tropica-MDCK co-culture models demonstrated a phenomenon known as atypical anoikis apoptosis, typically identified by distinctive 'flipping in' of cell membranes and disordered cytoskeletal frameworks. Conclusion: This study bridges the gap in the fundamental understanding of the intricate latticework involving vector-Leishmania-host and may inform drug development strategies.


Small parasites called Leishmania are passed to humans through the bites of sandflies. These parasites cause three deadly forms of disease: one that affects the organs, one that causes skin lesions and one that affects organ linings. This study looked at how Leishmania parasites behave when they enter through the skin. We found that when the parasites were in contact with cells, the cells changed their shape and lost contact with neighboring cells. This led to a type of cell death known as anoikis, a Greek term meaning 'homelessness'.


Subject(s)
Ill-Housed Persons , Leishmania donovani , Leishmania tropica , Leishmaniasis, Cutaneous , Leishmaniasis, Visceral , Humans , Anoikis , Epithelial Cells
14.
Eur J Med Chem ; 264: 115969, 2024 Jan 15.
Article in English | MEDLINE | ID: mdl-38039787

ABSTRACT

The persistence of drug resistance poses a significant obstacle to the advancement of efficacious malaria treatments. The remarkable efficacy displayed by 1,2,3-triazole-based compounds against Plasmodium falciparum highlights the potential of triazole conjugates, with diverse pharmacologically active structures, as potential antimalarial agents. We aimed to synthesize 7-dichloroquinoline-triazole conjugates and their structure-activity relationship (SAR) derivatives to investigate their anti-plasmodial activity. Among them, QP11, featuring a m-NO2 substitution, demonstrated efficacy against both chloroquine-sensitive and -resistant parasite strains. QP11 selectively inhibited FP2, a cysteine protease involved in hemoglobin degradation, and showed synergistic effects when combined with chloroquine. Additionally, QP11 hindered hemoglobin degradation and hemozoin formation within the parasite. Metabolic stability studies indicated high stability of QP11, making it a promising antimalarial candidate. In vivo evaluation using a murine malaria model demonstrated QP11's efficacy in eradicating parasite growth without neurotoxicity, presenting it as a promising compound for novel antimalarial development.


Subject(s)
Antimalarials , Malaria , Animals , Mice , Antimalarials/chemistry , Piperazine/pharmacology , Triazoles/chemistry , Chloroquine/pharmacology , Malaria/drug therapy , Plasmodium falciparum , Hemoglobins/metabolism , Hemoglobins/pharmacology , Hemoglobins/therapeutic use
15.
J Biomol Struct Dyn ; 42(5): 2449-2463, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37199276

ABSTRACT

Available anti-leishmanial drugs are associated with toxic side effects, necessitating the search for safe and effective alternatives. This study is focused on identifying traditional medicinal plant natural products for anti-leishmanial potential and possible mechanism of action. Compounds S and T. cordifolia residual fraction (TC-5) presented the best anti-leishmanial activity (IC50: 0.446 and 1.028 mg/ml) against promastigotes at 48 h and less cytotoxicity to THP-1 macrophages. These test agents elicited increased expression of pro-inflammatory cytokines; TNFα and IL-12. In infected untreated macrophages, NO release was suppressed but was significantly (p < 0.05) increased in infected cells treated with compound S. Importantly, Compound S was found to interact with LdTopoIIdimer in silico, resulting in a likely reduced ability of nucleic acid (dsDNA)-remodelling and, as a result, parasite proliferation in vitro. Thereby, Compound S possesses anti-leishmanial activity and this effect occurs via a Th1-mediated pro-inflammatory response. An increase in NO release and its inhibitory effect on LdTopoII may also contribute to the anti-leishmanial effect of compound S. These results show the potential of this compound as a potential starting point for the discovery of novel anti-leishmanial leads.Communicated by Ramaswamy H. Sarma.


Subject(s)
Antiprotozoal Agents , Leishmania donovani , Plants, Medicinal , Plant Extracts/pharmacology , Cytokines/metabolism , Antiprotozoal Agents/pharmacology
16.
Cureus ; 15(11): e48963, 2023 Nov.
Article in English | MEDLINE | ID: mdl-38111392

ABSTRACT

Mesenteric cysts are rare entities that are challenging to diagnose and treat because of their variable presentation and histological characteristics. They have been majorly classified into six groups, out of which, the chylo-lymphatic type is the most common. Their etiology remains poorly understood but is usually linked to lymphatic pathologies. They are thin-walled cysts, present in the mesentery of the gastrointestinal tract. They can mimic multiple other cysts; hence, their timely diagnosis is of utmost importance. Imaging techniques aid in the preoperative diagnosis along with a thorough physical exam. The mainstay of treatment is surgical excision of the cyst, which is essential to prevent the recurrence of malignant transformation; the usual method of removal is laparoscopy. Alternative treatments are aspiration and marsupialization, which are only utilised for specific cases. The recurrence rate is usually low after total excision, but follow-ups are recommended for early detection of recurrence. This case study highlights the significance of prompt diagnosis and proper management of mesenteric cysts.

17.
Sci Rep ; 13(1): 19157, 2023 11 06.
Article in English | MEDLINE | ID: mdl-37932378

ABSTRACT

Membrane-bound heat shock protein 70 (Hsp70) apart from its intracellular localization was shown to be specifically expressed on the plasma membrane surface of tumor but not normal cells. Although the association of Hsp70 with lipid membranes is well documented the exact mechanisms for chaperone membrane anchoring have not been fully elucidated. Herein, we addressed the question of how Hsp70 interacts with negatively charged phospholipids in artificial lipid compositions employing the X-ray reflectivity (XRR) studies. In a first step, the interactions between dioleoylphosphatidylcholine (DOPC) in the presence or absence of dioleoylphosphatidylserine (DOPS) and Hsp70 had been assessed using Quartz crystal microbalance measurements, suggesting that Hsp70 adsorbs to the surface of DOPC/DOPS bilayer. Atomic force microscopy (AFM) imaging demonstrated that the presence of DOPS is required for stabilization of the lipid bilayer. The interaction of Hsp70 with DOPC/DOPS lipid compositions was further quantitatively determined by high energy X-ray reflectivity. A systematic characterization of the chaperone-lipid membrane interactions by various techniques revealed that artificial membranes can be stabilized by the electrostatic interaction of anionic DOPS lipids with Hsp70.


Subject(s)
Artificial Cells , X-Rays , HSP70 Heat-Shock Proteins/metabolism , Lipid Bilayers/chemistry , Phospholipids/metabolism , Cell Membrane/metabolism
18.
J Pharm Bioallied Sci ; 15(Suppl 2): S895-S900, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37693957

ABSTRACT

Aim: Evaluation of the efficacy of different obturating techniques and assessment of the presence of voids in different regions of the canal. Materials and Methods: Sixty permanent single-rooted teeth with complete, mature root apices without any anatomic variation having straight patent root canals were included in the present study. Access cavity preparation followed by biomechanical preparation was done. Samples were divided into three groups-Group A: Single cone obturation, Group B: GuttaFlow 2, and Group C: GuttaCore, and obturation was carried out. The samples after obturation were stored at 370°C and 100% humidity in an incubator for 7 days to give adequate time for obturating materials to set. Cone beam computed tomography was performed with i-cat Cb 500 machine. The voids were checked on the root canal wall. The statistical analysis was done and the data after the statistical analysis was presented. Result: GuttaCore obturators presented a lesser volume of voids followed by GuttaFlow 2 than the single cone techniques. Conclusion: All the obturation techniques presented an inadequacy of obturation when the pre- and post-obturated volume of the root canal space was calculated. However, no statistically significant obturated volume differences were found between single cone and GuttaFlow 2 or between GuttaFlow 2 and GuttaCore system.

19.
Luminescence ; 38(12): 2018-2033, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37654050

ABSTRACT

This study performed a comparative investigation to explore the interaction mechanisms between two potential antimalarial compounds, JMI 346 and JMI 105, and human serum albumin (HSA), a vital carrier protein responsible for maintaining important biological functions. Our aim was to assess the pharmacological efficiency of these compounds while comprehensively analyzing their impact on the dynamic behavior and overall stability of the protein. A comprehensive array of multispectroscopic techniques, including UV-Vis. spectroscopy, steady-state fluorescence analysis, synchronous fluorescence spectroscopy, three-dimensional fluorescence and circular dichroism spectroscopy, docking studies, and molecular dynamics simulations, were performed to probe the intricate details of the interaction between the compounds and HSA. Our results revealed that both JMI 346 and JMI 105 exhibited promising pharmacological effectiveness within the context of malaria therapy. However, JMI 346 was found to exhibit a significantly higher affinity and only minor altered impact on HSA, suggesting a more favorable interaction with the protein on the dynamic behavior and overall stability of the protein in comparison to JMI 105. Further studies can build on these results to optimize the drug-protein interaction and enable the development of more potent and targeted antimalarial treatments.


Subject(s)
Antimalarials , Serum Albumin, Human , Humans , Serum Albumin, Human/chemistry , Antimalarials/pharmacology , Antimalarials/chemistry , Protein Binding , Circular Dichroism , Molecular Docking Simulation , Spectrometry, Fluorescence/methods , Thermodynamics , Binding Sites
20.
J Glob Antimicrob Resist ; 35: 67-75, 2023 12.
Article in English | MEDLINE | ID: mdl-37633420

ABSTRACT

OBJECTIVES: Artemisinin (ART) resistance in Plasmodium is threatening the artemisinin combination therapies-the first line of defence against malaria. ART resistance has been established to be mediated by the Plasmodium Kelch13 (PfK13) protein. For the crucial role of PfK13 in multiple pathways of the Plasmodium life cycle and ART resistance, it is imperative that we investigate its interacting partners. METHODS: We recombinantly expressed PfK13-p (Bric a brac/Poxvirus and zinc finger and propeller domains), generating anti-PfK13-p antibodies to perform co-immunoprecipitation assays and probed PfK13 interacting partners. Surface plasmon resonance and pull-down assays were performed to establish physical interactions of representative proteins with PfK13-p. RESULTS: The co-immunoprecipitation assays identified 17 proteins with distinct functions in the parasite life cycle- protein folding, cellular metabolism, and protein binding and invasion. In addition to the overlap with previously identified proteins, our study identified 10 unique proteins. Fructose-biphosphate aldolase and heat shock protein 70 demonstrated strong biophysical interaction with PfK13-p, with KD values of 6.6 µM and 7.6 µM, respectively. Additionally, Plasmodium merozoite surface protein 1 formed a complex with PfK13-p, which is evident from the pull-down assay. CONCLUSION: This study adds to our knowledge of the PfK13 protein in mediating ART resistance by identifying new PfK13 interacting partners. Three representative proteins-fructose-biphosphate aldolase, heat shock protein 70, and merozoite surface protein 1-demonstrated clear evidence of biophysical interactions with PfK13-p. However, elucidation of the functional relevance of these physical interactions are crucial in context of PfK13 role in ART resistance.


Subject(s)
Antimalarials , Artemisinins , Malaria, Falciparum , Parasites , Animals , Plasmodium falciparum/genetics , Antimalarials/pharmacology , Merozoite Surface Protein 1/therapeutic use , Drug Resistance , Protozoan Proteins/genetics , Mutation , Malaria, Falciparum/drug therapy , Artemisinins/pharmacology , HSP70 Heat-Shock Proteins/therapeutic use , Aldehyde-Lyases/therapeutic use , Fructose/therapeutic use
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