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1.
J Transl Med ; 22(1): 370, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637842

RESUMO

JAK-STAT signalling pathway inhibitors have emerged as promising therapeutic agents for the treatment of hair loss. Among different JAK isoforms, JAK3 has become an ideal target for drug discovery because it only regulates a narrow spectrum of γc cytokines. Here, we report the discovery of MJ04, a novel and highly selective 3-pyrimidinylazaindole based JAK3 inhibitor, as a potential hair growth promoter with an IC50 of 2.03 nM. During in vivo efficacy assays, topical application of MJ04 on DHT-challenged AGA and athymic nude mice resulted in early onset of hair regrowth. Furthermore, MJ04 significantly promoted the growth of human hair follicles under ex-vivo conditions. MJ04 exhibited a reasonably good pharmacokinetic profile and demonstrated a favourable safety profile under in vivo and in vitro conditions. Taken together, we report MJ04 as a highly potent and selective JAK3 inhibitor that exhibits overall properties suitable for topical drug development and advancement to human clinical trials.


Assuntos
Desenvolvimento de Medicamentos , Cabelo , Camundongos , Animais , Humanos , Camundongos Nus , Descoberta de Drogas , Janus Quinase 3
2.
Am J Transl Res ; 15(10): 5972-5983, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37969204

RESUMO

OBJECTIVE: Dengue is a viral infection endemic in more than 100 countries as per the WHO reports with approximately 5.2 million patients worldwide that spreads from mosquitoes to humans. Severe form of dengue fever can cause serious bleeding (low platelets) and death. Megakaryocytes are the immune cells responsible for the production of platelets. The molecular drivers behind platelet defects are mostly ambiguous. Here, we attempted to understand the distinct pathogen-elicited toll-like receptors (TLRs) functions in megakaryocyte biology. To understand the TLR induction and the molecular events that are governed in the mammalian system during dengue infection and to study TLR2-mediated cellular signaling-associated mechanisms with respect to their dimerization partners during dengue infection. METHODS: In this study, we used the human Megakaryoblastic cells, DAMI, and treated them with TLR agonists (LPS and Zymosan) and Dengue virus (DNV-II). RESULTS AND DISCUSSION: TLR2 could play an important role by dimerizing with TLR1, TLR4, and TLR6, which we induced for functional characterization. We observed that megakaryocyte maturation markers CD-41 and CD-61 were elevated. This augmentation under the LPS and Zymosan system along with DNV Infection was further confirmed. Our analysis also suggested that activation of miR-125b and MAPK signaling led to lipid droplet elevation. This led us to analyze TLR-mediated consequences and their impact on megakaryocyte development under diverse pathogen-elicited conditions. CONCLUSION: Pathogenic challenges associated with toll-like receptor system activation could further our understanding of the platelet biogenesis mechanistic pathways under various pathogenic circumstances.

3.
Bioorg Chem ; 138: 106606, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37210826

RESUMO

The 12R-lipoxygenase (12R-LOX), a (non-heme) iron-containing metalloenzyme belonging to the lipoxygenase (LOX) family catalyzes the conversion of arachidonic acid (AA) to its key metabolites. Studies suggested that 12R-LOX plays a critical role in immune modulation for the maintenance of skin homeostasis and therefore can be considered as a potential drug target for psoriasis and other skin related inflammatory diseases. However, unlike 12-LOX (or 12S-LOX) the enzyme 12R-LOX did not receive much attention till date. In our effort, the 2-aryl quinoline derivatives were designed, synthesized and evaluated for the identification of potential inhibitors of 12R-hLOX. The merit of selection of 2-aryl quinolines was assessed by in silico docking studies of a representative compound (4a) using the homology model of 12R-LOX. Indeed, in addition to participating in H-bonding with THR628 and LEU635 the molecule formed a hydrophobic interaction with VAL631. The desired 2-aryl quinolines were synthesized either via the Claisen-Schmidt condensation followed by one-pot reduction-cyclization or via the AlCl3 induced heteroarylation or via the O-alkylation approach in good to high (82-95%) yield. When screened against human 12R-LOX (12R-hLOX) in vitro four compounds (e.g. 4a, 4d, 4e and 7b) showed encouraging (>45%) inhibition at 100 µM among which 7b and 4a emerged as the initial hits. Both the compounds showed selectivity towards 12R-hLOX over 12S-hLOX, 15-hLOX and 15-hLOXB and concentration dependent inhibition of 12R-hLOX with IC50 = 12.48 ± 2.06 and 28.25 ± 1.63 µM, respectively. The selectivity of 4a and 7b towards 12R-LOX over 12S-LOX was rationalized with the help of molecular dynamics simulations. The SAR (Structure-Activity Relationship) within the present series of compounds suggested the need of a o-hydroxyl group on the C-2 phenyl ring for the activity. The compound 4a and 7b (at 10 and 20 µM) reduced the hyper-proliferative state and colony forming potential of IMQ-induced psoriatic keratinocytes in a concentration dependent manner. Further, both compounds decreased the protein levels of Ki67 and the mRNA expression of IL-17A in the IMQ-induced psoriatic-like keratinocytes. Notably, 4a but not 7b inhibited the production of IL-6 and TNF-α in the keratinocyte cells. In the preliminary toxicity studies (i.e. teratogenicity, hepatotoxicity and heart rate assays) in zebrafish both the compounds showed low safety (<30 µM) margin. Overall, being the first identified inhibitors of 12R-LOX both 4a and 7b deserve further investigations.


Assuntos
Quinolinas , Peixe-Zebra , Animais , Humanos , Peixe-Zebra/metabolismo , Araquidonato 12-Lipoxigenase/metabolismo , Pele/metabolismo , Quinolinas/farmacologia , Relação Estrutura-Atividade , Inibidores de Lipoxigenase/farmacologia , Simulação de Acoplamento Molecular
4.
J Nanobiotechnology ; 20(1): 317, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35794557

RESUMO

BACKGROUND: Exosomes are nano-sized vesicles secreted by various cells into the intra and extracellular space and hence is an integral part of biological fluids including milk. In the last few decades, many research groups have proved the potential of milk exosomes as a sustainable, economical and non-immunogenic drug delivery and therapeutic agent against different pathological conditions. However, its anti-viral properties still remain to be unearthed. METHODS: Here, we have been able to isolate, purify and characterize the milk derived exosomes from Cow (CME) and Goat (GME) and further studied its antiviral properties against Dengue virus (DENV), Newcastle Disease Virus strain Komarov (NDV-K) and Human Immunodeficiency Virus (HIV-1) using an in-vitro infection system. RESULTS: TEM, NTA and DLS analysis validated the appropriate size of the isolated cow and goat milk exosomes (30-150 nm). Real-time PCR and immunoblotting results confirmed the presence of several milk exosomal miRNAs and protein markers. Our findings suggest that GME significantly decreased the infectivity of DENV. In addition, we confirmed that GME significantly reduces DENV replication and reduced the secretion of mature virions. Furthermore, heat inactivation of GME did not show any inhibition on DENV infection, replication, and secretion of mature virions. RNase treatment of GME abrogates the anti-viral properties indicating direct role of exosomes in DENV inhibition. In addition GME inhibited the infectivity of NDV-K, but not HIV-1, suggesting that the GME mediated antiviral activity might be virus specific. CONCLUSION: This study demonstrates the anti-viral properties of milk exosomes and opens new avenues for the development of exosome-based therapies to treat viral diseases.


Assuntos
Vírus da Dengue , Exossomos , Animais , Antivirais/farmacologia , Bovinos , Exossomos/metabolismo , Feminino , Leite , Vírus da Doença de Newcastle
5.
Biomater Sci ; 10(11): 2917-2928, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35470821

RESUMO

Dengue is a mosquito-borne disease caused by the four serotypes of the dengue virus (DENV 1-4). It is growing at an alarming rate globally, which could be partly attributed to the lack of an effective therapeutic regimen. Therefore, strategies for developing an effective vaccine have gained more significance in the given scenario. Failure of the existing live attenuated vaccine candidates to mount effective and broader protection against all the four serotypes of DENV has generated a new interest in exploring novel strategies for augmenting the efficacy of non-infectious, non-replicating subunit vaccines. In the current study, we employed a new strategy of encapsulating the immunodominant EDIII domain of Envelop protein of all the serotypes of DENV (1-4) into PLGA nanoparticles separately. All four nano formulations were physically mixed to develop a tetravalent nano formulation in combination with TLR agonists. Further, we examined its immunological efficacy using a mouse and in vitro infection model system. Interestingly, our results demonstrate that majority of EDIII protein loaded PLGA nanoparticles were polydispersed and less than 1 µm in size with optimal encapsulation efficacy. Tetravalent nanoformulation along with TLR agonists (MPLA + R837) enhanced the magnitude of antigen-specific polyfunctional T cell response. It triggered robust antibody responses in mice concurrent with the increased level of genes involved in the programming of memory B-cell formation and the maintenance and maturation of GCs, leading to the formation of long-lived plasma cells secreting antigen-specific antibodies. Further assessment revealed that tetravalent nanoformulation in combination with TLR ligands upon immunization in mice aids in the enhanced production of serotype-specific neutralizing antibodies, which can effectively neutralize all the four serotypes of DENV (DENV 1-4). The findings of this study reveal a new strategy for enhancing the immunogenicity of vaccine candidates and might pave the way for the development of a tetravalent vaccine against all the serotypes of Dengue Virus.


Assuntos
Vacinas contra Dengue , Vírus da Dengue , Nanopartículas , Animais , Anticorpos Antivirais , Vacinas contra Dengue/genética , Vírus da Dengue/genética , Imunidade , Proteínas do Envelope Viral/genética
6.
Clin Immunol ; 237: 108981, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35306171

RESUMO

Neutralizing antibody-based passive immunotherapy could be an important therapeutic option against COVID-19. Herein, we demonstrate that equines hyper-immunized with chemically inactivated SARS-CoV-2 elicited high antibody titers with a strong virus-neutralizing potential, and F(ab')2 fragments purified from them displayed strong neutralization potential against five different SARS-CoV-2 variants. F(ab')2 fragments purified from the plasma of hyperimmunized horses showed high antigen-specific affinity. Experiments in rabbits suggested that the F(ab')2 displays a linear pharmacokinetics with approximate plasma half-life of 47 h. In vitro microneutralization assays using the purified F(ab')2 displayed high neutralization titers against five different variants of SARS-CoV-2 including the Delta variant, demonstrating its potential efficacy against the emerging viral variants. In conclusion, this study demonstrates that F(ab')2 generated against SARS-CoV-2 in equines have high neutralization titers and have broad target-range against the evolving variants, making passive immunotherapy a potential regimen against the existing and evolving SARS-CoV-2 variants in combating COVID-19.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/terapia , Cavalos , Humanos , Fragmentos Fab das Imunoglobulinas , Fragmentos de Imunoglobulinas , Coelhos
7.
Immunol Lett ; 242: 27-36, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35007662

RESUMO

Mycobacterium tuberculosis (M.tb) is a multifaceted bacterial pathogen known to infect more than 2 billion people globally. However, a majority of the individuals (>90%) show no overt clinical symptoms of active Tuberculosis (TB) and, it is reported that M.tb in these individuals resides in the latent form. Therefore, a huge burden of latently infected population poses serious threat to the human health. Inconsistent efficacy of BCG vaccine and poor understanding of latency-associated determinants contribute to the failure of combating M.tb. The discovery of DosR as the master regulator of dormancy, opened new avenues to understand the pathophysiology of the bacterium. Though the specific functions of various DosR genes are yet to be discovered, they have been reported as potent T-cell activators and could elicit strong protective immune responses. Rv0569 is a DosR-encoded conserved hypothetical protein overexpressed during dormancy. However, it is not clearly understood how this protein modulates the host immune response. In the present study, we have demonstrated that Rv0569 has a high antigenic index and induces enhanced secretion of Th1 cytokines IL-12p40 and TNF-α as compared to Th2 cytokine IL-10 in macrophages. Mechanistically, Rv0569 induced the transcription of these pro-inflammatory signatures through the activation of NF-κB pathway. Further, immunization of mice with DosR protein Rv0569 switched the immune response towards Th1-biased cytokine pattern, characterized by the enhanced production of IFN-γ, IL-12p40, and TNF-α. Rv0569 augmented the expansion of antigen-specific IFN-γ and IL-2 producing effector CD4+and CD8+ T-cells which are hallmarks of Th1 biased protective immunity. Additionally, IgG2a/IgG1 and IgG2b/IgG1 ratio in the serum of immunized mice further confirmed the ability of Rv0569 to skew Th1 biased immune response. In conclusion, we emphasize that Rv0569 has the ability to generate signals to switch on Th1-dominated responses and further suggest that it could be a potential vaccine candidate against latent M.tb infection.


Assuntos
Mycobacterium tuberculosis , Animais , Antígenos de Bactérias , Proteínas de Bactérias/genética , Linfócitos T CD8-Positivos , Citocinas/metabolismo , Humanos , Imunoglobulina G/metabolismo , Subunidade p40 da Interleucina-12 , Camundongos , Células Th1 , Fator de Necrose Tumoral alfa/metabolismo
8.
Obes Rev ; 22(4): e13221, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33569904

RESUMO

Obesity and obesogenic comorbidities have been associated with COVID-19 susceptibility and mortality. However, the mechanism of such correlations requires an in-depth understanding. Overnutrition/excess serum amino acid profile during obesity has been linked with inflammation and reprogramming of translational machinery through hyperactivation of amino acid sensor mammalian target of rapamycin (mTOR), which is exploited by SARS-CoV-2 for its replication. Conversely, we have shown that the activation of general control nonderepressible 2 (GCN2)-dependent amino acid starvation sensing pathway suppresses intestinal inflammation by inhibiting the production of reactive oxygen species (ROS) and interleukin-1 beta (IL-1ß). While activation of GCN2 has shown to mitigate susceptibility to dengue infection, GCN2 deficiency increases viremia and inflammation-associated pathologies. These findings reveal that the amino acid sensing pathway plays a significant role in controlling inflammation and viral infections. The current fact is that obesity/excess amino acids/mTOR activation aggravates COVID-19, and it might be possible that activation of amino acid starvation sensor GCN2 has an opposite effect. This article focuses on the amino acid sensing pathways through which host cells sense the availability of amino acids and reprogram the host translation machinery to mount an effective antiviral response. Besides, how SARS-CoV-2 hijack and exploit amino acid sensing pathway for its replication and pathogenesis is also discussed.


Assuntos
Aminoácidos/metabolismo , COVID-19/epidemiologia , N-Acetilexosaminiltransferases/fisiologia , Obesidade/epidemiologia , SARS-CoV-2 , Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/fisiopatologia , Comorbidade , Humanos , Inflamação , Obesidade/fisiopatologia , Biossíntese de Proteínas/fisiologia , SARS-CoV-2/fisiologia , Serina-Treonina Quinases TOR/fisiologia , Replicação Viral/fisiologia
9.
J Biomol Struct Dyn ; 39(4): 1417-1430, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32107969

RESUMO

Dengue virus (DENV) serine protease enzyme, i.e. NS2B-NS3pro (non-structural protein 2B-non-structural protein 3) has been approved as prime drug target for the drug discovery against dengue infection, because of its essential role in viral replication. This study demonstrates the potential of bioflavonoids from Azadirachta indica against dengue infection using computational and experimental approach. Initially, 49 bioflavonoids reported in Azadirachta indica were collected and virtually screened on the catalytic triad of DENV protease, results in the identification of kaempferol-3-O-rutinoside (-9.555 kcal/mol), rutin (-9.324 kcal/mol), hyperoside (-7.879 kcal/mol), and epicatechin (-7.622 kcal/mol) as potent viral protease inhibitors against reference compound quercetin (-6.94 kcal/mol). Subsequently, these docked complexes were analyzed for the stability via molecular dynamics simulations and free binding energy calculations, suggested the considerable stability of selected bioflavonoids with viral protease. Additionally, density functional theory and ADMET (Absorption, Distribution, Metabolism, Excretion and Toxicity) analysis indicated the least chemical reactivity and considerable medicinal properties, respectively for the screened bioflavonoids by comparison to quercetin. Accordingly, kaempferol 3-O-ß-rutinoside and epicatechin were evaluated at various concentrations for cell viability (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay) and in vitro antiviral activity (focus forming unit assay) against DENV-2 strain. The antiviral assay showed dose dependent inhibition of DENV-2 infectivity by the selected compounds while maximum 77.7% and 66.2% viral inhibition were recorded for 100 µM kaempferol 3-O-ß-rutinoside and 1000 µM epicatechin, respectively without significant cell toxicity. These results suggested the potential of bioflavonoids from Azadirachta indica in the development of effective drug against dengue infection.Communicated by Ramaswamy H. Sarma.


Assuntos
Azadirachta , Vírus da Dengue , Dengue , Antivirais/farmacologia , Antivirais/uso terapêutico , Dengue/tratamento farmacológico , Flavonoides/farmacologia , Simulação de Acoplamento Molecular , Inibidores de Proteases , Serina Proteases , Proteínas não Estruturais Virais
10.
Front Immunol ; 11: 1831, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32903536

RESUMO

Nutrient sensor GCN2 plays a crucial role in the maintenance of cellular homeostasis during the condition of amino acid deprivation. Dysfunction in the GCN2 signaling underlies several chronic metabolic diseases. Recent studies highlight the anti-viral potential of GCN2 against RNA viruses such as Sindbis and HIV. However, its effect on dengue virus (DENV) pathogenesis remains poorly understood. Herein, we report that GCN2 deficient cells show increased DENV replication and viral yield in the culture supernatants compared to WT cells infected with DENV. Notably, enhanced DENV replication in GCN2-/- cells is associated with increased COX-2/PGE2 signaling. Conversely, GCN2 overexpression/activation effectively contains DENV infection by inhibiting COX-2/PGE2 signaling. Mechanistically, deletion of GCN2 triggers enhanced production of COX-2/PGE2 through profound activation of Iκκ-NF-κB signaling pathway. Altogether our results unveil a hitherto unrecognized role of GCN2 in DENV pathogenesis, thereby suggesting that targeting the GCN2 pathway might offer a novel therapeutic intervention against DENV infection.


Assuntos
Ciclo-Oxigenase 2/metabolismo , Dengue/imunologia , Proteínas Serina-Treonina Quinases/imunologia , Transdução de Sinais/imunologia , Células Cultivadas , Dengue/metabolismo , Vírus da Dengue/imunologia , Humanos , Proteínas Serina-Treonina Quinases/metabolismo
11.
Nanoscale ; 12(3): 2028-2039, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31912859

RESUMO

Light-responsive nanoliposomes are being reported to induce cancer cell death through heat and reactive oxygen species (ROS). Nanoliposomes (CIR NLPs) encapsulating a near-infrared (NIR) light-sensitive dye, IR780, and a bioactive chlorophyll-rich fraction of Anthocephalus cadamba (CfAc) were synthesized and characterized. These CIR NLPs, when activated by NIR light, displayed localized synergistic cancer cell death under in vitro and in vivo conditions. We demonstrated a NIR light-mediated release of CfAc in cancer cells. The bioactive CfAc was selective in causing ROS generation (leading to autophagic cell death) in cancer cells, while normal healthy cells were unaffected. An increase in the intracellular ROS leading to enhanced lipidation of microtubule-associated protein light chain 3 (LC3-II) was observed only in cancer cells, while normal cells showed no increase in either ROS or LC3-II. In vivo analysis of CIR NLPs in an orthotopic mouse model showed better anti-tumorigenic potential through a combined effect (i.e. via heat and CfAc). We reported for the first time induction of selective and localized, bioactive phyto fraction-mediated autophagic cancer cell death through an NIR light trigger. The synergistic activation of ROS-mediated autophagy by light-triggered nanoliposomes can be a useful strategy for enhancing the anticancer potential of combinational therapies.


Assuntos
Autofagia/efeitos dos fármacos , Indóis , Luz , Nanopartículas , Neoplasias Experimentais , Extratos Vegetais , Espécies Reativas de Oxigênio/metabolismo , Rubiaceae/química , Animais , Humanos , Indóis/química , Indóis/farmacologia , Lipossomos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Células NIH 3T3 , Nanopartículas/química , Nanopartículas/uso terapêutico , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia
12.
Int J Biol Macromol ; 165(Pt B): 2869-2885, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33736288

RESUMO

Aminoacyl tRNA synthetases (aaRSs) are integral components of protein biosynthesis along with several non-canonical cellular processes. Inhibition studies of aaRSs presented these enzymes as promising drug targets in many pathogens, however aspartyl tRNA synthetase has not been studied in trypanosomatids despite its essentiality. Hence, full-length ORF of Leishmania donovani aspartyl tRNA synthetase (LdaspRS) was cloned and purified to homogeneity followed by molecular mass determination. The aminoacylation assay established that the purified protein performs its function optimally at physiological pH and temperature. The kinetic parameters of LdaspRS revealed the affinity of l-aspartate towards the enzyme to be very much lower than the cofactor. Our study also highlights the moonlighting function of LdaspRS to stimulate the pro-inflammatory cytokines and nitric oxide generation by host macrophage. Furthermore, CD and intrinsic tryptophan fluorescence measurements showed the changes in structural conformation at varying pH, denaturants and ligands. The modelled LdaspRS structure presented all the specific characteristics of class II aaRSs, while in silico study suggested binding of pyrimidine-derived inhibitors in its cofactor binding site with high affinity followed by validation using MD simulation. Altogether, this study could provide a platform for exploring LdaspRS to develop potential therapeutics against leishmaniasis.


Assuntos
Aspartato-tRNA Ligase/química , Aspartato-tRNA Ligase/metabolismo , Ácido Aspártico/metabolismo , Leishmania donovani/enzimologia , Aminoacilação , Animais , Aspartato-tRNA Ligase/genética , Aspartato-tRNA Ligase/imunologia , Clonagem Molecular , Evolução Molecular , Humanos , Concentração de Íons de Hidrogênio , Leishmania donovani/genética , Leishmania donovani/imunologia , Camundongos , Modelos Moleculares , Óxido Nítrico/metabolismo , Fases de Leitura Aberta , Conformação Proteica , Proteínas de Protozoários/química , Proteínas de Protozoários/genética , Proteínas de Protozoários/imunologia , Proteínas de Protozoários/metabolismo , Pirimidinas , Células RAW 264.7 , Células THP-1 , Temperatura , Triptofano/metabolismo
13.
Sci Signal ; 12(607)2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31719173

RESUMO

Specific reduction in the intake of proteins or amino acids (AAs) offers enormous health benefits, including increased life span, protection against age-associated disorders, and improved metabolic fitness and immunity. Cells respond to conditions of AA starvation by activating the amino acid starvation response (AAR). Here, we showed that mimicking AAR with halofuginone (HF) enhanced the magnitude and affinity of neutralizing, antigen-specific antibody responses in mice immunized with dengue virus envelope domain III protein (DENVrEDIII), a potent vaccine candidate against DENV. HF enhanced the formation of germinal centers (GCs) and increased the production of the cytokine IL-10 in the secondary lymphoid organs of vaccinated mice. Furthermore, HF promoted the transcription of genes associated with memory B cell formation and maintenance and maturation of GCs in the draining lymph nodes of vaccinated mice. The increased abundance of IL-10 in HF-preconditioned mice correlated with enhanced GC responses and may promote the establishment of long-lived plasma cells that secrete antigen-specific, high-affinity antibodies. Thus, these data suggest that mimetics of AA starvation could provide an alternative strategy to augment the efficacy of vaccines against dengue and other infectious diseases.


Assuntos
Aminoácidos/deficiência , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Formação de Anticorpos , Vacinas contra Dengue/farmacologia , Animais , Interleucina-10/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Piperidinas/farmacologia , Quinazolinonas/farmacologia
14.
Cytokine ; 123: 154780, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31344594

RESUMO

Dengue virus poses a considerable clinical problem, with the four closely related serotypes of dengue virus (DENV) infecting around 50-100 million people per year world-wide. The drastic increase in the dengue infection could be partly attributed to geographic expansion of the vector due to increasing urbanization, unavailability of specific antiviral therapies, licensed dengue vaccine, and poor understanding of the host immune responses. It has been reported that the immune-dominant envelope protein (E protein) domain III region (EDIII) of DENV is one of the most potent vaccine candidates because of its ability to trigger host immunity by inducing production of protective neutralizing antibodies. However, its role in the modulation of innate inflammatory responses hitherto remains unexplored. Herein, we demonstrate that EDIII protein of DENV induces pro-inflammatory signature by inducing production of inflammatory cytokines such as IL-1ß and TNF-α in THP-1 cells through NF-κB pathway. Also, we observed increase in the maturation of IL-1ß, which was found to be associated with increased ROS production and potassium efflux. Further, our findings reveal that the IL-1ß production by EDIII protein is mediated through caspase-1 and NLRP3 inflammasome activation. In conclusion this study unearths the role of DENV EDIII protein in modulating innate inflammatory responses, which might provide possible mechanism of pathogenesis and open-up new avenues for the development of therapeutics against DENV.


Assuntos
Vírus da Dengue/imunologia , Inflamassomos/imunologia , Interleucina-1beta/imunologia , Fator de Necrose Tumoral alfa/imunologia , Proteínas do Envelope Viral/imunologia , Caspase 1/imunologia , Vacinas contra Dengue/imunologia , Humanos , Inflamação/imunologia , NF-kappa B/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Células THP-1
15.
Biomater Sci ; 7(9): 3866-3875, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31309204

RESUMO

Photothermal therapy (PTT) is emerging as a promising treatment for skin cancer. Plasmon-resonant gold-coated liposome nanoparticles (Au Lipos NPs) specifically absorb Near Infra-Red (NIR) light resulting in localized hyperthermia (PTT). In the current study, curcumin (a hydrophobic anticancer agent) was entrapped in Au Lipos NPs as nanocrystals to act as an adjuvant for the PTT of melanoma. NIR light irradiation on Au Lipos Cur NPs triggered the release of curcumin nanocrystals which coalesce to form curcumin microcrystals (CMCs). An in situ"nano to micro" transition in the crystal state of curcumin was observed. This in situ transition leads to the formation of CMCs. These CMCs exhibited sustained release of curcumin for a prolonged duration (>10 days). The localized availability of curcumin aids in enhancing PTT by inhibiting the growth and mobility of cancer cells that escape PTT. In the in vitro modified scratch assay, the Au Lipos Cur NP + Laser group showed >1.5 fold enhanced therapeutic coverage when compared with the Au Lipos NP + Laser group. In vivo PTT studies performed in a B16 tumor model using Au Lipos Cur NPs showed a significant reduction of the tumor volume along with the localized release of curcumin in the tumor environment. It was observed that the localized release of curcumin enables an immediate adjuvant effect resulting in the enhancement of PTT.


Assuntos
Adjuvantes Farmacêuticos/química , Antineoplásicos/química , Curcumina/química , Ouro/química , Lipossomos/química , Nanopartículas Metálicas/química , Adjuvantes Farmacêuticos/administração & dosagem , Animais , Antineoplásicos/administração & dosagem , Linhagem Celular Tumoral , Movimento Celular , Quimioterapia Adjuvante , Cristalização , Curcumina/administração & dosagem , Feminino , Humanos , Interações Hidrofóbicas e Hidrofílicas , Hipertermia Induzida , Raios Infravermelhos , Melanoma/terapia , Nanopartículas Metálicas/administração & dosagem , Camundongos Endogâmicos C57BL , Tamanho da Partícula , Fototerapia/métodos , Neoplasias Cutâneas/terapia , Microambiente Tumoral
16.
Eur J Immunol ; 49(2): 277-289, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30578631

RESUMO

Immune cells sense and programme its cellular machinery appropriately to the environmental changes through the activation of cytoprotective adaptive pathway so-called the "integrated stress response (ISR)". However, the mechanisms implicated in ISR-induced protective responses are poorly understood. Here, we show that ISR activation by arsenite (Ar) results in suppression of IL-1ß production in macrophages and inhibition of DSS-induced colitis in a murine model through a novel posttranscriptional and translation regulatory (PTR) mechanism. Ar triggers PTR events through eIF2α-phosphorylation, which results in the attenuation of active polysome formation leading to the accumulation of translationally stalled IL-1ß mRNAs. Translationally stalled IL-1ß mRNAs recruit RNA-binding proteins (TIA-1/TIAR), resulting in the formation of RBP-RNA complexes known as stress granules (SGs). The SGs bound IL-1ß mRNAs might undergo degradation through induction of autophagy. Also, we show that Ar posttranslationally impairs processing and secretion of IL-1ß by diminishing inflammasome activation. Altogether, this study unveils a novel mechanism of IL-1ß regulation and further suggests that pharmacological activation of cytoprotective ISR pathway might provide an effective therapeutic intervention against inflammatory diseases.


Assuntos
Colite/imunologia , Interleucina-1beta/imunologia , Ativação de Macrófagos , Macrófagos/imunologia , Biossíntese de Proteínas/imunologia , Estabilidade de RNA/imunologia , Estresse Fisiológico/imunologia , Animais , Arsenitos/farmacologia , Linhagem Celular , Colite/induzido quimicamente , Colite/patologia , Sulfato de Dextrana/efeitos adversos , Sulfato de Dextrana/farmacologia , Inflamassomos/imunologia , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos BALB C , Estresse Fisiológico/efeitos dos fármacos
17.
Cell Immunol ; 334: 42-48, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30327138

RESUMO

Ulcerative colitis (UC) is a persistent inflammatory illness, which is clinically categorised as Inflammatory bowel disease (IBD), affecting millions of people worldwide. The precise cause behind the pathology of the disease remains unknown. However, the involvement of multiple factors including genetic predisposition, immunological deregulations, microbiota imbalance, and environmental triggers has been suggested. Amongst all these factors, the over-active immunological response reported in UC patients seems to be a promising target for therapy. Moreover, identification of gene signatures associated with disease onset and progression would help in better understanding of the molecular mechanisms involved in the disease pathogenesis. Here, we have conducted meta-analysis of gene expression profiles of UC patient microarray datasets accessible in public databases and further validated the in-silico findings in UC patients' blood samples. Our study reveals that UC pathogenesis perturbs expression of several inflammatory genes. In addition, we report a novel gene signature comprising of TIA1 (T cell restricted intracellular antigen) and TIAR (TIA1 related protein; also known as TIAL1), which were found to be significantly downregulated in UC patients. TIA1 and TIAR are RNA-binding proteins (RBPs), which function as a translational represser by binding to ARE sequences in the 3' UTR of mRNAs encoding inflammatory mediators including cytokines. Our findings demonstrate that deletion of TIAR using gene specific siRNAs in-vitro results in enhanced production of inflammatory cytokine IL-1ß. In conclusion, the findings of this study reveal that down regulation of TIA1/TIAR genes could be responsible for UC associated inflammation. This study highlights the usefulness of the meta-analysis approach in the identification of unique gene signatures that might deliver mechanistic insights into UC pathogenesis and possibly assist in discovery of prognostic markers and therapeutic interventions.


Assuntos
Colite Ulcerativa/imunologia , Proteínas de Ligação a RNA/imunologia , Transcriptoma/imunologia , Regiões 3' não Traduzidas/imunologia , Regulação para Baixo/imunologia , Expressão Gênica/imunologia , Humanos , Inflamação/imunologia , Doenças Inflamatórias Intestinais/imunologia , Interleucina-1beta/imunologia , RNA Mensageiro/imunologia , Antígeno-1 Intracelular de Células T/imunologia
18.
PLoS Biol ; 16(4): e2005317, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29621237

RESUMO

Activation of the amino acid starvation response (AAR) increases lifespan and acute stress resistance as well as regulates inflammation. However, the underlying mechanisms remain unclear. Here, we show that activation of AAR pharmacologically by Halofuginone (HF) significantly inhibits production of the proinflammatory cytokine interleukin 1ß (IL-1ß) and provides protection from intestinal inflammation in mice. HF inhibits IL-1ß through general control nonderepressible 2 kinase (GCN2)-dependent activation of the cytoprotective integrated stress response (ISR) pathway, resulting in rerouting of IL-1ß mRNA from translationally active polysomes to inactive ribocluster complexes-such as stress granules (SGs)-via recruitment of RNA-binding proteins (RBPs) T cell-restricted intracellular antigen-1(TIA-1)/TIA-1-related (TIAR), which are further cleared through induction of autophagy. GCN2 ablation resulted in reduced autophagy and SG formation, which is inversely correlated with IL-1ß production. Furthermore, HF diminishes inflammasome activation through suppression of reactive oxygen species (ROS) production. Our study unveils a novel mechanism by which IL-1ß is regulated by AAR and further suggests that administration of HF might offer an effective therapeutic intervention against inflammatory diseases.


Assuntos
Aminoácidos/deficiência , Autofagia/imunologia , Colite/imunologia , Interleucina-1beta/imunologia , Biossíntese de Proteínas , Proteínas Serina-Treonina Quinases/genética , Adaptação Fisiológica , Animais , Autofagia/efeitos dos fármacos , Células Cultivadas , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/genética , Regulação da Expressão Gênica , Inflamassomos/genética , Inflamassomos/imunologia , Interleucina-1beta/genética , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Piperidinas/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/imunologia , Inibidores da Síntese de Proteínas/farmacologia , Quinazolinonas/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/imunologia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/imunologia , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/imunologia , Espécies Reativas de Oxigênio/imunologia , Espécies Reativas de Oxigênio/metabolismo , Dodecilsulfato de Sódio/administração & dosagem , Inanição/genética , Inanição/imunologia , Estresse Fisiológico , Antígeno-1 Intracelular de Células T/genética , Antígeno-1 Intracelular de Células T/imunologia
19.
Int J Biol Macromol ; 110: 383-391, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-28964837

RESUMO

Development of multifunctional biodegradable nanomaterials to encapsulate hydrophobic drugs and their triggered release in cancer theranostics is a challenge. In the current study, we report the encapsulation of potent anticancer - chlorophyll rich biomolecular fraction from the plant Anthocephalus cadamba into a polymeric nanosystem. The biomolecular fraction was combined with an NIR dye IR-780 to make it photo-thermally active. It was evaluated for its combinatorial (biomolecular extract and photothermal mediated) synergistic cytotoxicity in skin cancer cells. The inherent fluorescence of chlorophyll in the fraction was deployed to understand the cellular uptake and drug release. Cellular uptake of hydrophobic CFAc was enhanced with the aid of nanoformulation. It was observed that photo stability of IR-780 improved when incorporated with CFAc in polymeric nanosystem, which resulted in enhanced photothermal transduction efficiency. The combinational approach exhibited synergistic cytotoxicity which can be applied for skin cancer theranostics.


Assuntos
Clorofila , Portadores de Fármacos , Hipertermia Induzida/métodos , Nanopartículas , Fotoquimioterapia/métodos , Rubiaceae/química , Neoplasias Cutâneas/terapia , Nanomedicina Teranóstica/métodos , Animais , Linhagem Celular Tumoral , Clorofila/química , Clorofila/farmacologia , Portadores de Fármacos/farmacologia , Camundongos , Nanopartículas/química , Nanopartículas/uso terapêutico , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
20.
Nanoscale ; 9(38): 14641-14653, 2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-28936523

RESUMO

The application of nanotechnology in vaccinology has fuelled rapid advancement towards the design and development of nanovaccines. Nanoparticles have been found to enhance vaccine efficacy through the spatiotemporal orchestration of antigen delivery to secondary lymphoid organs and antigen-presentation by Antigen Presenting Cells (APCs) synchronized with stimulation of innate and adaptive immune responses. Metal based nanoparticles (MNPs) have been extensively engineered for the generation of nanovaccines owing to their intrinsic adjuvant-like properties and immunomodulatory functions. Furthermore, mesoporous nanocapsules of late have attracted researchers due to their precise size and exclusive capacity to encapsulate a wide range of biomolecules and their sustained release at the targeted sites. Herein, we have designed a novel mesoporous ZnO nanocapsule (mZnO) having a size of ∼12 nm with an average pore diameter of 2.5 nm, using a surfactant-free sonochemical method and investigated its immunomodulatory properties by using Ova loaded mZnO nanocapsules [mZnO(Ova)] in a mice model. Our findings show that mZnO(Ova) administration steered the enhanced expansion of antigen-specific T-cells and induction of IFN-γ producing effector CD4+ and CD8+ T-cells. Also, antigen-specific IgG levels were enriched in both the serum and lymph nodes of mZnO(Ova) immunized mice. Further, we noticed a substantial increase in serum IgG2a or IgG2b levels and IFN-γ secretion in Ova restimulated splenocytes from mZnO(Ova) immunized mice, indicating that mZnO(Ova) skew Th1 type immune response. Overall, the uniqueness of mZnO nanocapsules in terms of the defined particle to pore numbers ratio (maximum of three cavities per particle) allows loading antigens efficiently. Given these features in combination with its immunomodulatory characteristics reinforces the idea that mZnO could be used as an effective antigen-adjuvant platform for the development of novel nano-based vaccines against multiple diseases.


Assuntos
Adjuvantes Imunológicos , Apresentação de Antígeno , Antígenos/administração & dosagem , Nanocápsulas , Óxido de Zinco/química , Animais , Imunoglobulina G/sangue , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina , Linfócitos T/imunologia
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