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1.
J Environ Manage ; 367: 121795, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39106794

RESUMO

In this paper, a versatile heterogeneous nanocatalyst was fabricated employing a self-assembly technique. To commence, Fe3O4 MNPs were coated with a thin layer of SiO2 using the stobbers method. Subsequently, the surface was further functionalized with 3-CPMS, followed by a reaction with a Schiff base. Finally, nickel NPs were deposited on the surface through in situ deposition, forming the Fe3O4@SiO2@3-CPMS@L-Ni magnetic nanocatalyst. The architecture of this magnetic nanocatalyst was meticulously characterized through an array of sophisticated techniques: XRD, FT-IR, SEM, TEM, BET and VSM. The XRD diffraction pattern confirmed the presence of Fe3O4 MNPs, SiO2, and Ni peaks, providing evidence for successful synthesis. Moreover, the successful functionalization with a Schiff base was demonstrated by the presence of an azomethane peak in the FTIR spectra of the synthesized nanocatalyst. The fabricated nanocatalyst was adeptly utilized for the reduction of 4-NP, NB, and MO demonstrating a remarkably elevated rate of catalytic efficacy. Moreover, this catalyst was effortlessly retrievable through the application of an external magnet, and it maintained its catalytic prowess across at least six consecutive cycles. The utilization of water as an environmentally friendly solvent, coupled with the utilization of abundant and cost-effective nickel catalyst instead of the costly Pd or Pt catalysts, along with the successful recovery and scalability of the catalyst, render this method highly advantageous from both environmental and economic perspectives for the reduction of 4-NP, NB, and MO.


Assuntos
Níquel , Dióxido de Silício , Níquel/química , Catálise , Dióxido de Silício/química , Nitrobenzenos/química , Nitrofenóis/química , Compostos Azo/química , Espectroscopia de Infravermelho com Transformada de Fourier
2.
Dose Response ; 21(3): 15593258231185457, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37654727

RESUMO

Nanoparticles have shown promising potential for efficient drug delivery, circumventing biological interferences like immunological and renal clearance and mechanical and enzymatic destruction. However, a handful of research papers have questioned the biomedical use of metal-based nanoparticles like cadmium telluride quantum dots (CdTe-QDs) for their cytotoxic, genotoxic, and carcinogenic potential. Herein, we examined the effects of CdTe-QD NPs on gene expression profile of hepatocellular carcinoma (Huh-7) cell line. Huh-7 cells were treated with CdTe-QD NPs (10 µg/ml for 6, 12, and 24 hours, and 25 µg/ml for 6 and 12 hours), and transcriptomic analysis was performed using microarray to evaluate the global gene expression profile. Differential expressed genes (DEGs) were observed for both the doses (10 and 25 µg/ml) of CdTe-QD NPs at different time points. Gene ontology (GO) analysis revealed that genes involved in molecular function of cell cycle, organizational injury and abnormalities, cell death and survival, gene expression, cancer, organismal survival, and cellular development were differentially expressed. Overall, we have demonstrated differential expression of several genes, involved in maintaining cell survival, metabolism, and genome integrity. These findings were confirmed by RT-qPCR study for some canonical pathway genes signifying possible implication in NP toxicity-mediated cell survival and inhibition of cell death.

3.
Front Immunol ; 13: 1020624, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36389723

RESUMO

Background: SARS-CoV-2 infects through the respiratory route and triggers inflammatory response by affecting multiple cell types including type II alveolar epithelial cells. SARS-CoV-2 triggers signals via its Spike (S) protein, which have been shown to participate in the pathogenesis of COVID19. Aim: Aim of the present study was to investigate the effect of SARS-CoV2 on type II alveolar epithelial cells, focusing on signals initiated by its S protein and their impact on the expression of inflammatory mediators. Results: For this purpose A549 alveolar type II epithelial cells were exposed to SARS CoV2 S recombinant protein and the expression of inflammatory mediators was measured. The results showed that SARS-CoV-2 S protein decreased the expression and secretion of IL8, IL6 and TNFα, 6 hours following stimulation, while it had no effect on IFNα, CXCL5 and PAI-1 expression. We further examined whether SARS-CoV-2 S protein, when combined with TLR2 signals, which are also triggered by SARS-CoV2 and its envelope protein, exerts a different effect in type II alveolar epithelial cells. Simultaneous treatment of A549 cells with SARS-CoV-2 S protein and the TLR2 ligand PAM3csk4 decreased secretion of IL8, IL6 and TNFα, while it significantly increased IFNα, CXCL5 and PAI-1 mRNA expression. To investigate the molecular pathway through which SARS-CoV-2 S protein exerted this immunomodulatory action in alveolar epithelial cells, we measured the induction of MAPK/ERK and PI3K/AKT pathways and found that SARS-CoV-2 S protein induced the activation of the serine threonine kinase AKT. Treatment with the Akt inhibitor MK-2206, abolished the inhibitory effect of SARS-CoV-2 S protein on IL8, IL6 and TNFα expression, suggesting that SARS-CoV-2 S protein mediated its action via AKT kinases. Conclusion: The findings of our study, showed that SARS-CoV-2 S protein suppressed inflammatory responses in alveolar epithelial type II cells at early stages of infection through activation of the PI3K/AKT pathway. Thus, our results suggest that at early stages SARS-CoV-2 S protein signals inhibit immune responses to the virus allowing it to propagate the infection while in combination with TLR2 signals enhances PAI-1 expression, potentially affecting the local coagulation cascade.


Assuntos
Células Epiteliais Alveolares , COVID-19 , Humanos , Células Epiteliais Alveolares/metabolismo , SARS-CoV-2 , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt , Fator de Necrose Tumoral alfa , RNA Viral , Inibidor 1 de Ativador de Plasminogênio , Interleucina-6 , Interleucina-8 , Receptor 2 Toll-Like
4.
Cell Mol Biol (Noisy-le-grand) ; 68(4): 66-74, 2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35988286

RESUMO

Dengue virus (DENV) causes dengue, which is a very common mosquito-borne viral disease. The global incidence of dengue has increased dramatically in recent decades. About half of the world's population is now at risk. This virus is widespread throughout the tropics, which are influenced by rainfall, temperature, and humidity; however, severe dengue has a higher risk of death when not managed timely. To describe Dengue virus helicase ATP binding domain (HABD) protein in biochemically characterized. Sequences analysis, structure modeling, secondary structure prediction, ATPase assay, unwinding assay, RNA binding assay. HABD has RNA-dependent ATPase and helicase activity which are crucial proteins that participate in the unwinding of double-stranded DNA or RNA by utilizing ATP. RNA binding proteins and DEAD-box RNA helicases have been revealed to contribute to viral replication. Moreover, DEAD-box RNA helicases have been demonstrated to be involved in several features of cellular metabolism of RNA, for example, transcription, splicing, biogenesis, ribosomal processing of RNA, etc. In the present study, we have mainly focused on the Dengue virus's helicase ATP binding domain (HABD) and observed that HABD contains RNA-dependent ATPase and unwinding activity at different concentrations and time points.


Assuntos
Vírus da Dengue , Dengue , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Proteínas de Transporte/metabolismo , RNA Helicases DEAD-box/química , RNA Helicases DEAD-box/metabolismo , Dengue/genética , Vírus da Dengue/genética , Vírus da Dengue/metabolismo , RNA/metabolismo
5.
Pak J Pharm Sci ; 35(3): 827-834, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35791483

RESUMO

Moringa oleifera plant grows in many countries worldwide and being utilized as a customary medication. The current study aimed to investigate the biological effect of Moringa oleifera leaf extract (MOE) alone or in combination with silver nanoparticles (AgNPs) on colon cancer, microbial cell growth. MOE was utilized in the green synthesis of AgNPs. The characterization of AgNPs was done by UV-Vis-spectrophotometry, X-ray diffraction (XRD) and scanning electron microscopy (SEM). MOE was tested for their sugars, active biomolecules, ROS, protein contents. Results revealed that created AgNPs are about 61 nm in diameter. There were no detectable sugar and protein in MOE, but it contains ROS and active biomolecules. MOE and MOE+AgNPs exerted mild antibacterial action and increased the number of apoptotic cells and p53 protein expression of HT-29 colon cancer cells. MOE and MOE+AgNPs could arrest HT-29 cells at G2/M phase and stimulate splenic cell growth. Both extract preparations showed antioxidant activities. Because MOE and MOE+AgNP stimulated immune cells and activated apoptosis in cancer cells, these preparations can be utilized as anticancer agents.


Assuntos
Neoplasias do Colo , Nanopartículas Metálicas , Moringa oleifera , Extratos Vegetais , Prata , Neoplasias do Colo/tratamento farmacológico , Células HT29 , Humanos , Moringa oleifera/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Espécies Reativas de Oxigênio , Prata/farmacologia
6.
Drug Des Devel Ther ; 16: 1963-1974, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35783198

RESUMO

Introduction: Numerous drugs with potent toxicity against cancer cells are available for treating malignancies, but therapeutic efficacies are limited due to their inefficient tumor targeting and deleterious effects on non-cancerous tissue. Therefore, two improvements are mandatory for improved chemotherapy 1) novel delivery techniques that can target cancer cells to deliver anticancer drugs and 2) methods to specifically enhance drug efficacy within tumors. The loading of inert drug carriers with anticancer agents and peptides which are able to bind (target) tumor-related proteins to enhance tumor drug accumulation and local cytotoxicity is a most promising approach. Objective: To evaluate the anticancer efficacy of Chitosan nanoparticles loaded with human growth hormone hGH fragment 176-191 peptide plus the clinical chemotherapeutic doxorubicin in comparison with Chitosan loaded with doxorubicin alone. Methods: Two sets of in silico experiments were performed using molecular docking simulations to determine the influence of hGH fragment 176-191 peptide on the anticancer efficacy of doxorubicin 1) the binding affinities of hGH fragment 176-191 peptide to the breast cancer receptors, 2) the effects of hGH fragment 176-191 peptide binding on doxorubicin binding to these same receptors. Further, the influence of hGH fragment 176-191 peptide on the anticancer efficacy of doxorubicin was validated using viability assay in Human MCF-7 breast cancer cells. Results: In silico analysis suggested that addition of the hGH fragment to doxorubicin-loaded Chitosan nanoparticles can enhance doxorubicin binding to multiple breast cancer protein targets, while photon correlation spectroscopy revealed that the synthesized dual-loaded Chitosan nanoparticles possess clinically favorable particle size, polydispersity index, as well as zeta potential. Conclusion: These dual-loaded Chitosan nanoparticles demonstrated greater anti-proliferative activity against a breast cancer cell line (MCF-7) than doxorubicin-loaded Chitosan. This dual-loading strategy may enhance the anticancer potency of doxorubicin and reduce the clinical side effects associated with non-target tissue exposure.


Assuntos
Antineoplásicos , Neoplasias da Mama , Quitosana , Hormônio do Crescimento Humano , Nanopartículas , Antineoplásicos/química , Neoplasias da Mama/tratamento farmacológico , Quitosana/química , Quitosana/farmacologia , Doxorrubicina , Feminino , Humanos , Células MCF-7 , Simulação de Acoplamento Molecular , Nanopartículas/química , Peptídeos/uso terapêutico
7.
Saudi J Biol Sci ; 28(8): 4751-4761, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34354463

RESUMO

Probiotics have attracted considerable attention because of their ability to ameliorate disease and prevent cancer. In this study, we examined the immunomodulatory effects of a Streptococcus thermophilus probiotic on the intestinal mucosa azoxymethane-induced colon cancer. Sixty female mice were divided into four groups (n = 15 each). One group of untreated mice was used as a control (C group). Another mouse group was injected with azoxymethane once weekly for 8 weeks to induce colon cancer (CC group). Finally, two groups of mice were continuously treated twice per week from week 2 to 16 with either the Lactobacillus plantarum (Lac CC group) or S. thermophilus (Strep CC group) bacterial strain pre-and post-treatment as performed for the CC group. Remarkably, Tlr2, Ifng, Il4, Il13, Il10, and Tp53 transcription were significantly downregulated in the Strep CC intestinal mucosa group. Additionally, IL2 expression was decreased significantly in the Strep CC mouse serum, whereas TNFα was remarkably elevated compared to that in the CC, Lac CC, and untreated groups. This study suggested that Streptococcus thermophilus did not interrupt or hinder colon cancer development in mice when administered as a prophylactic.

8.
Front Immunol ; 12: 683800, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34248968

RESUMO

The major cause of death in SARS-CoV-2 infected patients is due to de-regulation of the innate immune system and development of cytokine storm. SARS-CoV-2 infects multiple cell types in the lung, including macrophages, by engagement of its spike (S) protein on angiotensin converting enzyme 2 (ACE2) receptor. ACE2 receptor initiates signals in macrophages that modulate their activation, including production of cytokines and chemokines. IL-1R-associated kinase (IRAK)-M is a central regulator of inflammatory responses regulating the magnitude of TLR responsiveness. Aim of the work was to investigate whether SARS-CoV-2 S protein-initiated signals modulate pro-inflammatory cytokine production in macrophages. For this purpose, we treated PMA-differentiated THP-1 human macrophages with SARS-CoV-2 S protein and measured the induction of inflammatory mediators including IL6, TNFα, IL8, CXCL5, and MIP1a. The results showed that SARS-CoV-2 S protein induced IL6, MIP1a and TNFα mRNA expression, while it had no effect on IL8 and CXCL5 mRNA levels. We further examined whether SARS-CoV-2 S protein altered the responsiveness of macrophages to TLR signals. Treatment of LPS-activated macrophages with SARS-CoV-2 S protein augmented IL6 and MIP1a mRNA, an effect that was evident at the protein level only for IL6. Similarly, treatment of PAM3csk4 stimulated macrophages with SARS-CoV-2 S protein resulted in increased mRNA of IL6, while TNFα and MIP1a were unaffected. The results were confirmed in primary human peripheral monocytic cells (PBMCs) and isolated CD14+ monocytes. Macrophage responsiveness to TLR ligands is regulated by IRAK-M, an inactive IRAK kinase isoform. Indeed, we found that SARS-CoV-2 S protein suppressed IRAK-M mRNA and protein expression both in THP1 macrophages and primary human PBMCs and CD14+ monocytes. Engagement of SARS-CoV-2 S protein with ACE2 results in internalization of ACE2 and suppression of its activity. Activation of ACE2 has been previously shown to induce anti-inflammatory responses in macrophages. Treatment of macrophages with the ACE2 activator DIZE suppressed the pro-inflammatory action of SARS-CoV-2. Our results demonstrated that SARS-CoV-2/ACE2 interaction rendered macrophages hyper-responsive to TLR signals, suppressed IRAK-M and promoted pro-inflammatory cytokine expression. Thus, activation of ACE2 may be a potential anti-inflammatory therapeutic strategy to eliminate the development of cytokine storm observed in COVID-19 patients.


Assuntos
Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/imunologia , Síndrome da Liberação de Citocina/imunologia , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Macrófagos/imunologia , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Regulação da Expressão Gênica , Humanos , Imunidade Inata , Mediadores da Inflamação/metabolismo , Quinases Associadas a Receptores de Interleucina-1/genética , Interleucina-6/genética , Interleucina-6/metabolismo , Lipopolissacarídeos/imunologia , Macrófagos/virologia , Ligação Proteica , Células THP-1 , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
9.
Oxid Med Cell Longev ; 2021: 5834418, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34257812

RESUMO

Despite recent advancements in cisplatin (cis-diamminedichloroplatinum II) and other platinum-based chemotherapeutic drugs for treating solid tumors, their uses are limited by either in terms of toxicity and/or acquired drug resistance. These side effects have a dangerous problem with higher dose for severe patients. To overcome the low therapeutic ratio of the free drug, a polymeric nanoparticle drug delivery system has been explored promoting delivery of cisplatin to tumors. Recently, the applications of nanoparticles (NPs) have been underlined for encouraging the effects of chemotherapeutic drugs in cancerous cells. The intention of this project is to assess the potential of poly lactic-co-glycolic acid (PLGA) nanoparticles (NPs) for enhancing the effects of anticancer drug cisplatin. For the purpose, we have synthesized PLGA-cisplatin nanoparticles for increasing its bioavailability and studied the comparative cytotoxicity of free cisplatin and PLGA-cisplatin against MCF-7 cancer cell lines and HEK-293 normal cell lines. We have also analyzed the hallmarks of PLGA-cisplatin-induced apoptosis. The outcomes of this study may provide the possibility of delivery of anticancer drug to their specific site, which could minimize toxicity and optimize the drug efficacy.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Cisplatino/uso terapêutico , Glicolatos/metabolismo , Poliésteres/metabolismo , Antineoplásicos/farmacologia , Apoptose , Linhagem Celular Tumoral , Cisplatino/farmacologia , Feminino , Humanos
10.
Dose Response ; 19(2): 15593258211019880, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34177396

RESUMO

Cadmium telluride quantum dots (CdTe-QDs) are acquiring great interest in terms of their applications in biomedical sciences. Despite earlier sporadic studies on possible oncogenic roles and anticancer properties of CdTe-QDs, there is limited information regarding the oncogenic potential of CdTe-QDs in cancer progression. Here, we investigated the oncogenic effects of CdTe-QDs on the gene expression profiles of Chang cancer cells. Chang cancer cells were treated with 2 different doses of CdTe-QDs (10 and 25 µg/ml) at different time intervals (6, 12, and 24 h). Functional annotations helped identify the gene expression profile in terms of its biological process, canonical pathways, and gene interaction networks activated. It was found that the gene expression profiles varied in a time and dose-dependent manner. Validation of transcriptional changes of several genes through quantitative PCR showed that several genes upregulated by CdTe-QD exposure were somewhat linked with oncogenesis. CdTe-QD-triggered functional pathways that appear to associate with gene expression, cell proliferation, migration, adhesion, cell-cycle progression, signal transduction, and metabolism. Overall, CdTe-QD exposure led to changes in the gene expression profiles of the Chang cancer cells, highlighting that this nanoparticle can further drive oncogenesis and cancer progression, a finding that indicates the merit of immediate in vivo investigation.

11.
Saudi J Biol Sci ; 28(1): 116-124, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33424288

RESUMO

Cyclic adenosine monophosphate (cAMP) and calcium ions (Ca2+) are two chemical molecules that play a central role in the stimulus-dependent secretion processes within cells. Ca2+ acts as the basal signaling molecule responsible to initiate cell secretion. cAMP primarily acts as an intracellular second messenger in a myriad of cellular processes by activating cAMP-dependent protein kinases through association with such kinases in order to mediate post-translational phosphorylation of those protein targets. Put succinctly, both Ca2+ and cAMP act by associating or activating other proteins to ensure successful secretion. Calcineurin is one such protein regulated by Ca2+; its action depends on the intracellular levels of Ca2+. Being a phosphatase, calcineurin dephosphorylate and other proteins, as is the case with most other phosphatases, such as protein phosphatase 2A (PP2A), PP2C, and protein phosphatase-1 (PP1), will likely be activated by phosphorylation. Via this process, calcineurin is able to affect different intracellular signaling with clinical importance, some of which has been the basis for development of different calcineurin inhibitors. In this review, the cAMP-dependent calcineurin bio-signaling, protein-protein interactions and their physiological implications as well as regulatory signaling within the context of cellular secretion are explored.

12.
Saudi J Biol Sci ; 27(10): 2617-2621, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32994719

RESUMO

BACKGROUND: Previous reports have shown that pulmonary and systemic hypergamma-globulinemia in CF patients is a reflection of chronic pulmonary infection. Infection with Pseudomonas aeruginosa is known to have major prognostic significance in patients CF. This study aims to identify the incidence of immunoglobulins (especially: IgG, and IgE) in a cohort of CF patients. METHODS: A total of 297 patients recruited all over the country's region for this study were a as part of the CF registry data from 1st January 1984 to 1st June 2016. All patients had their immunoglobulin levels measured by enzyme link immunosorbent assay (ELISA) in 3 stages, at presentation and two follow-ups. RESULTS: Of the 297 patients recruited, 139 (46.8%) were males while 158 (53.2%) were females. IgA and IgM levels were found not to have risen above the previously reported levels in healthy individuals in all stages. On the contrary, IgE level increased from 209.51 ± 32.30 KU/L to 303.58 ± 37.11 KU/L from baseline to stage 3 while IgG level rose from 12.26 ± 0.43 mg/mL to 17.17 ± 1.68 mg/mL for baseline and stage 3 respectively all above previously reported levels in healthy individuals. CONCLUSION: This study establishes a potential for the use of IgE and IgG in disease diagnosis as well as the prognostic implications. However, further study is needed to identify the role of infection or medications in relation to the rise of both IgE and IgG with advancement of age and progression of disease severity which may inherently confound the observed results.

13.
Lab Invest ; 98(3): 272-282, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29251738

RESUMO

NM23 proteins NDPK-A and -B bind to the cystic fibrosis (CF) protein CFTR in different ways from kinases such as PKA, CK2 and AMPK or linkers to cell calcium such as calmodulin and annexins. NDPK-A (not -B) interacts with CFTR through reciprocal AMPK binding/control, whereas NDPK-B (not -A) binds directly to CFTR. NDPK-B can activate G proteins without ligand-receptor coupling, so perhaps NDPK-B's binding influences energy supply local to a nucleotide-binding site (NBD1) needed for CFTR to function. Curiously, CFTR (ABC-C7) is a member of the ATP-binding cassette (ABC) protein family that does not obey 'clan rules'; CFTR channels anions and is not a pump, regulates disparate processes, is itself regulated by multiple means and is so pleiotropic that it acts as a hub that orchestrates calcium signaling through its consorts such as calmodulin/annexins. Furthermore, its multiple partners make CFTR dance to different tunes in different cellular and subcellular locations as it recycles from the plasma membrane to endosomes. CFTR function in airway apical membranes is inhibited by smoking which has been dubbed 'acquired CF'. CFTR alone among family members possesses a trap for other proteins that it unfurls as a 'fish-net' and which bears consensus phosphorylation sites for many protein kinases, with PKA being the most canonical. Recently, the site of CFTR's commonest mutation has been proposed as a knock-in mutant that alters allosteric control of kinase CK2 by log orders of activity towards calmodulin and other substrates after CFTR fragmentation. This link from CK2 to calmodulin that binds the R region invokes molecular paths that control lumen formation, which is incomplete in the tracheas of some CF-affected babies. Thus, we are poised to understand the many roles of NDPK-A and -B in CFTR function and, especially lumen formation, which is defective in the gut and lungs of many CF babies.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Nucleosídeo NM23 Difosfato Quinases/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Calmodulina/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/química , Humanos , Domínios Proteicos , Isoformas de Proteínas
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