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1.
Artigo em Inglês | MEDLINE | ID: mdl-38584531

RESUMO

BACKGROUND: Colorectal cancer (CRC) remains a significant contributor to mortality, often exacerbated by metastasis and chemoresistance. Novel therapeutic strategies are imperative to enhance current treatments. The dysregulation of the PI3K/Akt signaling pathway is implicated in CRC progression. This study investigates the therapeutic potential of Wortmannin, combined with 5-fluorouracil (5-FU), to target the PI3K/Akt pathway in CRC. METHODS: Anti-migratory and antiproliferative effects were assessed through wound healing and MTT assays. Apoptosis and cell cycle alterations were evaluated using Annexin V/Propidium Iodide Apoptosis Assay. Wortmannin's impact on the oxidant/antioxidant equilibrium was examined via ROS, SOD, CAT, MDA, and T-SH levels. Downstream target genes of the PI3K/AKT pathway were analyzed at mRNA and protein levels using RTPCR and western blot, respectively. RESULTS: Wortmannin demonstrated a significant inhibitory effect on cell proliferation, modulating survivin, cyclinD1, PI3K, and p-Akt. The PI3K inhibitor attenuated migratory activity, inducing E-cadherin expression. Combined Wortmannin with 5-FU induced apoptosis, increasing cells in sub-G1 via elevated ROS levels. CONCLUSION: This study underscores Wortmannin's potential in inhibiting CRC cell growth and migration through PI3K/Akt pathway modulation. It also highlights its candidacy for further investigation as a promising therapeutic option in colorectal cancer treatment.

2.
Biomed Pharmacother ; 170: 115942, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38042111

RESUMO

Bladder cancer cells possess unique adaptive capabilities: shaped by their environment, cells face a complex chemical mixture of metabolites and xenobiotics accompanied by physiological mechanical cues. These responses might translate into resistance to chemotherapeutical regimens and can largely rely on autophagy. Considering molecules capable of rewiring tumor plasticity, compounds of natural origin promise to offer valuable options. Fungal derived metabolites, such as bafilomycin and wortmannin are widely acknowledged as autophagy inhibitors. Here, their potential to tune bladder cancer cells´ adaptability to chemical and physical stimuli was assessed. Additionally, dietary occurring mycotoxins were also investigated, namely deoxynivalenol (DON, 0.1-10 µM) and fusaric acid (FA, 0.1-1 mM). Endowing a Janus' face behavior, DON and FA are on the one side described as toxins with detrimental health effects. Concomitantly, they are also explored experimentally for selective pharmacological applications including anticancer activities. In non-cytotoxic concentrations, bafilomycin (BAFI, 1-10 nM) and wortmannin (WORT, 1 µM) modified cell morphology and reduced cancer cell migration. Application of shear stress and inhibition of mechano-gated PIEZO channels reduced cellular sensitivity to BAFI treatment (1 nM). Similarly, for FA (0.5 mM) PIEZO1 expression and inhibition largely aligned with the modulatory potential on cancer cells motility. Additionally, this study highlighted that the activity profile of compounds with similar cytotoxic potential (e.g. co-incubation DON with BAFI or FA with WORT) can diverge substantially in the regulation of cell mechanotransduction. Considering the interdependence between tumor progression and response to mechanical cues, these data promise to provide a novel viewpoint for the study of chemoresistance and associated pathways.


Assuntos
Antineoplásicos , Neoplasias da Bexiga Urinária , Humanos , Mecanotransdução Celular , Wortmanina/farmacologia , Autofagia , Antineoplásicos/farmacologia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Canais Iônicos
3.
J Mol Endocrinol ; 71(3)2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37924639

RESUMO

Several studies provide evidence that erythropoietin (EPO) could play an important role in the recovery of the heart subjected to ischemia-reperfusion. In this regard, it has been suggested that EPO could be involved in protein kinase B (Akt) activation as a cell survival protein. The aim of the present study was to investigate the effects of EPO on the Akt/glycogen synthase kinase 3 beta (GSK-3ß) pathway in the presence or absence of wortmannin (W, Akt inhibitor) and its relationship with mitochondrial morphology and function preservation in ischemic-reperfused rat hearts. EPO improved the functional recovery of the heart subjected to ischemia-reperfusion, reduced the release of CK and the infarct size, and promoted preservation of the mitochondrial structure. Moreover, it reduced tissue lactate content and preserved glycogen in order to prevent ischemia. The results showed greater Akt activation, accompanied by preservation of swelling and mitochondrial calcium retention capacity, as well as an increase in ATP synthesis capacity. These results were accompanied by an inhibition of GSK-3ß, suggesting regulation of Akt on the opening of the mitochondrial permeability transition pore. All these beneficial effects exerted by acute treatment with EPO were prevented by W. The present study provided novel evidence that EPO not only enhances intrinsic activation of Akt during myocardial ischemia-reperfusion but also promotes GSK-3ß inhibition, contributing to mitochondrial structure and function preservation.


Assuntos
Cardiotônicos , Eritropoetina , Coração , Proteínas Proto-Oncogênicas c-akt , Traumatismo por Reperfusão , Animais , Ratos , Eritropoetina/farmacologia , Glicogênio Sintase Quinase 3 beta/metabolismo , Isquemia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Cardiotônicos/farmacologia , Coração/efeitos dos fármacos
4.
J Plant Physiol ; 291: 154137, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37984048

RESUMO

Vacuolar sorting is critically important in plants as it regulates the mobilization of proteins and plays a major role in important agricultural traits like yield and seed protein content. Vacuolar sorting receptors (VSRs) are integral membrane proteins that mediate protein trafficking from the Golgi apparatus to the vacuole via the intermediate membrane-bound prevacuolar compartment (PVC)/multivesicular body (MVB). VSR proteins, such as an 80 kD (BP-80) from pea, also serve as markers for PVC/MVB. Dissecting VSR-mediated protein trafficking pathways may provide ways to enhance agronomic traits and crop yield. Green fluorescence protein (GFP) fusions with the seven Arabidopsis (Arabidopsis thaliana) VSRs were previously shown to localize to PVCs in transgenic tobacco BY-2 cells. The Rice (Oryza sativa) genome contains seven VSRs (OsVSR1-7), but little is known about their subcellular localizations. Here we studied the subcellular localization of OsVSR1-7 b y using a reporter approach, in which GFP-OsVSR1-7 fusions containing the transmembrane domain (TMD) and cytoplasmic tail (CT) of individual OsVSR were expressed in the protoplasts of rice, transgenic tobacco BY-2 cells and transgenic rice plants. Immunofluorescent labelling studies and confocal laser scanning microscope observation demonstrated that the seven OsVSRs are localized to PVCs and form ring-like structures upon wortmannin treatment. Therefore, we have verified the subcellular localization of OsVSR1-7 in this study. The OsVSRs tagged with GFP can serve as PVCs/MVBs markers in rice for the future studies.


Assuntos
Arabidopsis , Oryza , Vacúolos/metabolismo , Oryza/genética , Oryza/metabolismo , Transporte Proteico , Wortmanina/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Fluorescência Verde/metabolismo
5.
Biofactors ; 49(6): 1174-1188, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37345860

RESUMO

Human T lymphotropic virus type 1 (HTLV-1) infection can cause adult T-cell lymphoblastic leukemia (ATLL), an incurable, chemotherapy-resistant malignancy. In a quest for new therapeutic targets, our study sought to determine the levels of AKT, mTOR, and PI3K in ATLL MT-2 cells, HTLV-1 infected NIH/3T3 cells (Inf-3T3), and HTLV-1 infected patients (Carrier, HAM/TSP, and ATLL). Furthermore, the effects of rigosertib, wortmannin, and rapamycin on the PI3K/Akt/mTOR pathway to inhibit the proliferation of ATLL cells were examined. The results showed that mRNA expression of Akt/PI3K/mTOR was down-regulated in carrier, HAM/TSP, and ATLL patients, as well as MT-2, and Inf-3T3 cells, compared to the healthy individuals and untreated MT-2 and Inf-3T3 as controls. However, western blotting revealed an increase in the phosphorylated and activated forms of AKT and mTOR. Treating the cells with rapamycin, wortmannin, and rigosertib decreased the phosphorylated forms of Akt and mTOR and restored their mRNA expression levels. Using these inhibitors also significantly boosted the expression of the pro-apoptotic genes, Bax/Bcl-2 ratio as well as the expression of the tumor suppressor gene p53 in the MT-2 and Inf-3T3cells. Rigosertib was more potent than wortmannin and rapamycin in inducing sub-G1 and G2-M cell cycle arrest, as well as late apoptosis in the Inf-3T3 and MT-2 cells. It also synergized the cytotoxic effects of vincristine. These findings demonstrate that HTLV-1 downregulation of the mRNA level may occur as a negative feedback response to increased PI3K-Akt-mTOR phosphorylation by HTLV-1. Therefore, using rigosertib alone or in combination with common chemotherapy drugs may be beneficial in ATLL patients.


Assuntos
Infecções por HTLV-I , Vírus Linfotrópico T Tipo 1 Humano , Leucemia-Linfoma de Células T do Adulto , Adulto , Animais , Camundongos , Humanos , Leucemia-Linfoma de Células T do Adulto/tratamento farmacológico , Leucemia-Linfoma de Células T do Adulto/genética , Leucemia-Linfoma de Células T do Adulto/metabolismo , Sirolimo/farmacologia , Wortmanina , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases , Infecções por HTLV-I/genética , Serina-Treonina Quinases TOR/genética , RNA Mensageiro
6.
Polymers (Basel) ; 15(7)2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37050295

RESUMO

Chitosan oligosaccharide (COS) is a breakdown product of chitin, a polymer of N-acetyl-D-glucosamine. COS promotes barrier function in intestinal epithelial cells. However, the exact mechanism of COS-induced barrier function remains unknown. This study was aimed to explore the intricate signaling cascades in the junction barrier induced by COS (100 µg/mL) in human intestinal epithelial cells (T84 cells). COS (100 µg/mL) promoted tight junction assembly and increased transepithelial electrical resistance (TEER). COS inhibited FITC-dextran flux in T84 cell monolayers at 2 h, 4 h, 6 h and 24 h post treatment. In addition, the effect of COS on TEER and FITC-dextran flux was abrogated by pre-incubation of wortmannin (2 µM), an AKT (protein kinase B) inhibitor, at 2 h and 4 h post treatment, indicating that COS-induced tight junction integrity was mediated at least in part by AKT activation. COS-induced TEER was amplified at 24 h and 48 h post treatment by pre-incubation with SC79 (2.5 µM), an AKT activator. Moreover, COS induced inhibition of extracellular signal-regulated kinase (ERK) in T84 cells. Wortmannin and SC79 pre-incubation promoted ERK activation and ERK inhibition, respectively, suggesting that COS-induced ERK inhibition was mediated by AKT. Collectively, this study reveals that COS promotes junction barrier integrity via regulating PI3K/AKT and ERK signaling intricate interplay in T84 cell monolayers. COS may be beneficial in promoting junction barrier in intestinal disorders.

7.
Autophagy ; 19(4): 1164-1183, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36026492

RESUMO

Macroautophagy/autophagy is a multistep degradative process that is essential for maintaining cellular homeostasis and is often dysregulated during disease. Systematically quantifying flux through this pathway is critical for gaining fundamental insights and effectively modulating this process. Established methods to quantify flux use steady-state measurements, which provide limited information about the perturbation and the cellular response. We present a theoretical and experimental framework to measure autophagic steps in the form of rates under non-steady-state conditions. We use this approach to measure temporal responses to rapamycin and wortmannin treatments, two commonly used autophagy modulators. We quantified changes in autophagy rates in as little as 10 min, which can establish direct mechanisms for autophagy perturbation before feedback begins. We identified concentration-dependent effects of rapamycin on the initial and temporal progression of autophagy rates. We also found variable recovery time from wortmannin's inhibition of autophagy, which is further accelerated by rapamycin. Furthermore, we applied this approach to study the effect of serum and glutamine starvation on autophagy. Serum starvation led to a rapid and transient increase in all the rates. Glutamine starvation led to a decrease in the rates on a longer timescale. In summary, this new approach enables the quantification of autophagy flux with high sensitivity and temporal resolution and facilitates a comprehensive understanding of this process.


Assuntos
Autofagia , Glutamina , Humanos , Glutamina/metabolismo , Wortmanina/farmacologia , Wortmanina/metabolismo , Lisossomos/metabolismo , Sirolimo/farmacologia
8.
Med Oncol ; 40(1): 35, 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36460880

RESUMO

Breast cancer cells abnormally express vasopressin (AVP) and its receptors. The effect of AVP is largely orchestrated through its downstream signaling and by receptor-mediated endocytosis (RME), in which Dynamin 2 (Dyn2) plays an integral role in vesicle closure. In this work, luminal A breast cancer cells were treated with AVP, and then Dynasore (DYN) was employed to inhibit Dyn2 to explore the combined effect of AVP and Dyn2 inhibition on the survival of breast cancer cells. The results revealed that DYN alone demonstrated a concentration-dependent cytotoxic effect in AVP untreated cells. Apoptosis developed in 29.7 and 30.3% of cells treated with AVP or AVP+DYN, respectively, compared to 32.5% in cells treated with Wortmannin (Wort, a selective PI3K pathway inhibitor). More apoptosis was observed when cells were treated with DYN+Wort in presence or absence of exogenous AVP. Besides, 2 or 4- fold increases in the expression of Bax and Caspase-3, were observed in cells exposed to AVP in absence or presence of DYN, respectively. This was associated with higher levels of the autophagy marker (LC3II protein). Meanwhile, the activation of Akt protein, sequentially decreased in the same pattern. Cell's invasion decreased when they were exposed to AVP alone or combined with DYN or/and Wort. Conclusively, although many reports suggested the proliferative effect of AVP, the results predict the antiproliferative and antimetastatic effects of 100 nM AVP in luminal A breast cancer cells. However, the hormone did not enhance the cytotoxic effect of Dyn 2 or PI3K pathway inhibition. Summary of the Dynamin 2 independent AVP antiproliferative effects. Breast cancer cells expresses AVP as a Prohormone (A). At high dose of AVP, the hormone is liganded with AVP receptor (B) to initiate RME, where the endosomed complex (C) is degraded through the endosome-lysosome system, as a part of signal management. These events consume soluble Dyn2 in neck closure and vesicle fission (D). This makes the cells more substitutable to the direct apoptotic effect of DYN (E). Alternatively, at lower AVP doses the liganded AVP may initiate cAMP-mediated downstream signaling (F) and cellular proliferation. In parallel, Wort inhibits PIP2-PIP3 conversion (G) and the subsequent inhibition of PI3K/Akt/mTOR pathway leading to cell death.


Assuntos
Neoplasias da Mama , Fosfatidilinositol 3-Quinases , Humanos , Feminino , Proteínas Proto-Oncogênicas c-akt , Dinamina II , Neoplasias da Mama/tratamento farmacológico , Vasopressinas , Apoptose
9.
J Oral Biosci ; 64(4): 452-460, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36113760

RESUMO

OBJECTIVES: Several studies suggest that Glycyrrhiza glabra (GG) extract could be a useful supplemental source for various cancer treatments. However, very few studies on oral cancer (OC) have been conducted. The present study was aimed at exploring the bioactive compounds (bioactives) along with the mode of action of GG against OC using network pharmacology. METHODS: Liquid chromatography-mass spectrometry/mass spectrometry was used to identify and analyze compounds from GG. Public databases were used to identify genes associated with the selected bioactives and OC. With the help of Cytoscape software, the association between bioactive and common genes was built, visualized, and investigated. Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) was used to investigate protein-protein interactions for intergenic interactions. Finally, the pathway enrichment analysis of common genes was done using the Database for Annotation, Visualization, and Integrated Discovery (DAVID) platform. RESULTS: Overall, 378 bioactives were identified in GG. Using public databases, an entire 254 bioactive-related genes and 734 OC-related genes were recognized, with 48 common genes. Cytoscape analysis showed wortmannin as the key bioactive and androgen receptor as the hub gene. The DAVID results revealed that the significant mechanism of action of GG against OC may be to induce apoptosis of cancer cells by deactivating the PI3K-AKT signaling pathway. CONCLUSION: The key active components and mechanisms of action of GG against OC were investigated. The present study provides scientific suggestions to support the clinical outcome of GG for OC along with a research foundation for additional elaboration on the important bioactives and mechanisms of GG against OC.


Assuntos
Glycyrrhiza , Neoplasias Bucais , Farmacologia em Rede , Fosfatidilinositol 3-Quinases , Extratos Vegetais/farmacologia , Neoplasias Bucais/tratamento farmacológico
10.
Theriogenology ; 189: 42-52, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35724451

RESUMO

Modulation of phosphoinositide 3-kinase/protein kinase B/phosphatase and tensin homologue (PI3K/AKT/PTEN) pathway in mammals yields mixed results. A deep understanding of its regulation can be a powerful tool for better in vitro blastocyst production. This systematic review aims to map the evidence of PI3K/AKT/PTEN pathway modulation during in vitro maturation (IVM), to assess its effects on meiosis resumption and nuclear maturation progression of mammalian oocytes, and their impacts on embryo development and quality. A total of 1058 articles were screened in three databases, and 22 articles were included. Fifty-two IVM assessments were identified, among which 11 evaluated blastocyst yield. Three PI3K inhibitors (3-methyladenine, Wortmannin, and LY294002) and one AKT inhibitor (SH6) were investigated. The impact of this pathway modulation on meiosis resumption in swines and murines was not well established, depending on the inhibitor used, concentration, and media supplementation, while in bovines, resumption seems to be independent of PI3K/AKT/PTEN pathway. However, progression to metaphase II (MII) is highly controlled by this pathway on both bovines and swines. Studies that focused on the inhibition reversibility showed that the removal of the modulator produced MII rates similar to the control group. Experiments that aimed to temporarily block meiosis resumption or reduce PI3K activity resulted in blastocyst production equal to or even higher than control groups. Altogether, these data indicate the paramount potential of this pathway as a possible strategy to improve overall in vitro embryo production efficiency, by synchronizing both nuclear and cytoplasmic maturation.


Assuntos
Técnicas de Maturação in Vitro de Oócitos , Fosfatidilinositol 3-Quinases , Animais , Técnicas de Maturação in Vitro de Oócitos/métodos , Técnicas de Maturação in Vitro de Oócitos/veterinária , Mamíferos , Meiose , Oócitos/fisiologia , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Monoéster Fosfórico Hidrolases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Tensinas/metabolismo
11.
Methods Mol Biol ; 2462: 59-69, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35152380

RESUMO

The abscisic acid (ABA) is a key hormone for stress tolerance. The balance between growth/development and stress responses is crucial for the optimal course of plant life meaning that plants need to control the timing and extent of ABA pathway activation. In this regard, protein turnover regulation by means of both the ubiquitin-proteasome system (UPS) and non-26S proteasome endomembrane trafficking pathways, plays a critical role in the regulation of ABA signaling activation and deactivation. Over the last few years, the ubiquitination of ABA receptors PYRABACTIN RESISTANCE1 (PYR1)/PYR1-LIKE (PYL)/REGULATORY COMPONENTS OF ABA RECEPTORS (RCAR) at the plasma membrane by the RING between RING fingers (RBR)-type E3 ligase RING FINGER OF SEED LONGEVITY1 (RSL1) triggering their internalization through the clathrin-mediated endocytosis (CME) pathway, followed by their endosomal trafficking and delivery to the vacuole for degradation, was reported. For this process, the direct role of some components of the endosomal sorting complex required for transport (ESCRT) machinery, that is, FYVE DOMAIN-CONTAINING PROTEIN 1 (FYVE1)/FYVE DOMAIN PROTEIN REQUIRED FOR ENDOSOMAL SORTING 1 (FREE1) and VACUOLAR PROTEIN SORTING23A (VPS23A) members of ESCRT-I complex, and ALG-2 INTERACTING PROTEIN-X (ALIX) associated protein of ESCRT-III, was reported. In this chapter, we will detail two methods for imaging endosomal trafficking of ABA receptor proteins by confocal microscopy: (a) colocalization of GFP-PYL4 (also known as RCAR10) and CLATHRIN LIGHT CHAIN 2 (CLC2)-mOrange in clathrin-coated vesicles in Nicotiana benthamiana leaf cells and (b) localization of GFP-PYL4 into Wortmannin (WM)-enlarged late endosomes in Arabidopsis thaliana root cells.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ácido Abscísico/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Endossomos/metabolismo , Ubiquitinação
12.
Cells ; 10(11)2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34831441

RESUMO

Astrocytes are a main target of JC polyomavirus (JCPyV) in the central nervous system (CNS), where the destruction of these cells, along with oligodendrocytes, leads to the fatal disease progressive multifocal leukoencephalopathy (PML). There is no cure currently available for PML, so it is essential to discover antivirals for this aggressive disease. Additionally, the lack of a tractable in vivo models for studying JCPyV infection makes primary cells an accurate alternative for elucidating mechanisms of viral infection in the CNS. This research to better understand the signaling pathways activated in response to JCPyV infection reveals and establishes the importance of the PI3K/AKT/mTOR signaling pathway in JCPyV infection in primary human astrocytes compared to transformed cell lines. Using RNA sequencing and chemical inhibitors to target PI3K, AKT, and mTOR, we have demonstrated the importance of this signaling pathway in JCPyV infection of primary astrocytes not observed in transformed cells. Collectively, these findings illuminate the potential for repurposing drugs that are involved with inhibition of the PI3K/AKT/mTOR signaling pathway and cancer treatment as potential therapeutics for PML, caused by this neuroinvasive virus.


Assuntos
Astrócitos/metabolismo , Astrócitos/virologia , Vírus JC/fisiologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Butadienos/farmacologia , Células Cultivadas , Humanos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Modelos Biológicos , Nitrilas/farmacologia , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Wortmanina/farmacologia
13.
J Gen Virol ; 102(7)2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34328830

RESUMO

The 5' capped, message-sense RNA genome of Chikungunya virus (CHIKV) utilizes the host cell machinery for translation. Translation is regulated by eIF2 alpha at the initiation phase and by eIF4F at cap recognition. Translational suppression by eIF2 alpha phosphorylation occurs as an early event in many alphavirus infections. We observe that in CHIKV-infected HEK293 cells, this occurs as a late event, by which time the viral replication has reached an exponential phase, implying its minimal role in virus restriction. The regulation by eIF4F is mediated through the PI3K-Akt-mTOR, p38 MAPK and RAS-RAF-MEK-ERK pathways. A kinetic analysis revealed that CHIKV infection did not modulate AKT phosphorylation, but caused a significant reduction in p38 MAPK phosphorylation. It caused degradation of phospho-ERK 1/2 by increased autophagy, leaving the PI3K-Akt-mTOR and p38 MAPK pathways for pharmacological targeting. mTOR inhibition resulted in moderate reduction in viral titre, but had no effect on CHIKV E2 protein expression, indicating a minimal role of the mTOR complex in virus replication. Inhibition of p38 MAPK using SB202190 caused a significant reduction in viral titre and CHIKV E2 and nsP3 protein expression. Furthermore, inhibiting the two pathways together did not offer any synergism, indicating that inhibiting the p38 MAPK pathway alone is sufficient to cause restriction of CHIKV replication. Meanwhile, in uninfected cells the fully functional RAS-RAF-MEK-ERK pathway can circumvent the effect of p38 MAPK inhibition on cap-dependent translation. Thus, our results show that host-directed antiviral strategies targeting cellular p38 MAPK are worth exploring against Chikungunya as they could be selective against CHIKV-infected cells with minimal effects on uninfected host cells.


Assuntos
Autofagia , Vírus Chikungunya/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Imidazóis/farmacologia , Biossíntese de Proteínas , Piridinas/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Apoptose , Linhagem Celular Tumoral , Vírus Chikungunya/genética , Vírus Chikungunya/fisiologia , Regulação para Baixo , Inibidores Enzimáticos/farmacologia , Células HEK293 , Humanos , Sistema de Sinalização das MAP Quinases , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosforilação , Capuzes de RNA , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo , Replicação Viral/efeitos dos fármacos
14.
Am J Transl Res ; 13(6): 6236-6247, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34306363

RESUMO

The aim of this study was to show the effects of autophagy inhibitor Wortmannin and antiangiogenic-proapoptotic Thalidomide on autophagy and apoptosis markers in 4T1 breast cancer cells in vitro and in vivo. The half-maximal inhibitory concentration (IC50) values of 4T1 cells for Wortmannin and Thalidomide were evaluated by Methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay. After cancer formation in 28 BALB/C female mice, drugs were administered for seven days. Cells and tissue sections were evaluated for anti-phosphoinositide 3-kinase (PI3K), anti- the microtubule-associated protein 1 light chain3 (MAPLC3ß), anti-caspase 8, anti-caspase 9, and anti-caspase 3 immunoreactivities by immunohistochemical staining and apoptosis by Terminal Transferase dUTP Nick End Labeling (TUNEL) assay. Both PI3K and MAPLC3ß immunoreactivities decreased in all treatments when compared to control group except Thalidomide treatment in primary cancer tissue. The caspase 3, 8, and 9 immunoreactivities were increased in all treatment groups and TUNEL positive cells were the highest in the Wortmannin and Thalidomide group. Our findings suggest that autophagy is an important mechanism for 4T1 cells and both Wortmannin and Thalidomide treatments inhibit autophagy and induce apoptosis. In primary cancer tissues, autophagy was not effective as in vitro. The treatment of Wortmannin and Thalidomide increased the apoptotic cells in vivo independent from autophagy inhibition. Different results may be because of microenvironment. Further studies must be done to elucidate the effect of microenvironment.

15.
J Med Case Rep ; 15(1): 313, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-34088358

RESUMO

BACKGROUND: Sugammadex is a synthetic γ-cyclodextrin derivative designed to selectively bind to steroidal neuromuscular blocking agents and reverse their effects. Although many cases of sugammadex-induced anaphylaxis have been reported, few studies have investigated the underlying mechanism. CASE PRESENTATION: A 55-year-old Japanese man underwent a laryngectomy under general anesthesia. One month before laryngectomy, he had undergone laryngoscopy under general anesthesia and received sugammadex administration without causing hypersensitivity. He had no history of allergies. The operation was finished without complications. Shortly after sugammadex administration, his blood pressure dropped to approximately 70 mmHg, and his heart rate increased to 110 beats/minute with systemic erythema. Suspecting anaphylaxis, he was treated with the intravenous injection of phenylephrine, D-chlorpheniramine, and hydrocortisone. After these treatments, his cardiovascular condition stabilized. Eight months after the event, skin prick tests and intradermal tests with all agents used during general anesthesia were performed. Intradermal tests showed positive results only for sugammadex. Subsequently, basophil activation tests with CD203c were performed using sugammadex, γ-cyclodextrin, and positive controls (anti-immunoglobulin-E and formyl-methionyl-leucyl-phenylalanine). In addition to both controls, sugammadex, but not γ-cyclodextrin, induced significant upregulation of CD203c expression. We performed additional basophil activation tests with wortmannin, an inhibitor of phosphoinositide 3-kinase, to investigate the mechanism underlying sugammadex-induced basophil activation. The inhibitory effect of wortmannin on basophil activation due to sugammadex was similar to that of anti-immunoglobulin-E, suggesting an immunoglobulin-E-dependent mechanism. Although the patient showed no hypersensitivity after the first exposure of sugammadex, anaphylaxis appeared after the second administration. Because most cases of sugammadex-induced anaphylaxis reportedly appeared after first administration, this seems to be a rare case. CONCLUSIONS: In the present case, sugammadex-induced anaphylaxis might have occurred through an immunoglobulin-E-dependent mechanism and not involve γ-cyclodextrin as an epitope. Physicians should pay attention to the occurrence of sugammadex-induced anaphylaxis even when the patient has a history of safe administration of sugammadex.


Assuntos
Anafilaxia , gama-Ciclodextrinas , Anafilaxia/induzido quimicamente , Epitopos , Humanos , Imunoglobulina E , Masculino , Pessoa de Meia-Idade , Fosfatidilinositol 3-Quinases , Sugammadex , gama-Ciclodextrinas/efeitos adversos
16.
Arch Pharm Res ; 44(6): 605-620, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34170496

RESUMO

Recent studies have shown that pre and postconditioning the heart with sodium thiosulfate (STS) attenuate ischemia-reperfusion (IR) injury. However, the underlying mechanism involved in the cardioprotective signaling pathway is not fully explored. This study examined the existing link of STS mediated protection (as pre and post-conditioning agents) with PI3K, mTOR, and mPTP signaling pathways using its respective inhibitors. STS was administered to the isolated perfused rat heart through Kreb's Heinselit buffer before ischemia (precondition: SIPC) and reperfusion (postcondition: SPOC) in the presence and absence of the PI3K, mTOR, and mPTP signaling pathway inhibitors (wortmannin, rapamycin, and glibenclamide respectively). SIPC failed to improve the IR injury-induced altered cardiac hemodynamics, increased infarct size, and the release of cardiac injury markers in the presence of these inhibitors. On the other hand, the SPOC protocol effectively rendered the cardioprotection even in the PI3K/mTOR/KATP inhibitors presence. Interestingly, the SIPC's identified mode of action viz reduction in oxidative stress and the preservation of mitochondrial function were lost in the inhibitors' presence. Based on the above results, we conclude that the underlying mechanism of SIPC mediated cardioprotection works via the PI3K/mTOR/KATP signaling pathway axis activation.


Assuntos
Trifosfato de Adenosina/metabolismo , Precondicionamento Isquêmico Miocárdico/métodos , Traumatismo por Reperfusão Miocárdica/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Tiossulfatos/administração & dosagem , Trifosfato de Adenosina/antagonistas & inibidores , Animais , Preparação de Coração Isolado/métodos , Masculino , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Ratos , Ratos Wistar , Serina-Treonina Quinases TOR/antagonistas & inibidores
17.
Life Sci ; 277: 119621, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34004255

RESUMO

Effective telomerase-molecular targeted cancer therapy might be a promising approach for the efficient treatment of ovarian cancer. Therefore, folate-functionalized PLGA nanoparticles (NPs) were co-loaded with hTERT siRNA, Wortmannin (Wtmn), as a potent PI3K inhibitor, and magnetic nanoparticle (MNPs) as a theranostic agent to gain a multifunctional NPs for targeted drug delivery as well as molecular targeted therapy. 1HNMR, FTIR, DLS, FE-SEM and TEM were applied to characterize the synthesized NPs. In vitro discharge pattern for siRNA and Wtmn from the dual drug-loaded NPs showed an early fast release followed by a constant release up to 200 h. According to the MRI analysis, by increasing the concentration of Fe3O4 in NPs, the weaker T2 signal intensity was enhanced, and a considerable contrast was detected in the MRI images. MTT assay and median-effect analysis showed that the Wtmn/siRNA-loaded MNPs-PLGA-F2 NPs display the most synergistic cytotoxicity on the SKOV-3 ovarian cancer cells. Moreover, the Wtmn/siRNA-loaded MNPs-PLGA-FA NPs could significantly reduce the expression of hTERT, AKT, and p-AKT than the single drug-encapsulated NPs (P < 0.05). Taken together, the findings showed that the multifunctional NPs relying on combinatorial therapy might have considerable potential for effective telomerase-molecular targeted therapy of ovarian cancer.


Assuntos
Sistemas de Liberação de Medicamentos , Nanopartículas Magnéticas de Óxido de Ferro/química , Terapia de Alvo Molecular , Neoplasias Ovarianas/tratamento farmacológico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , RNA Interferente Pequeno/genética , Telomerase/antagonistas & inibidores , Wortmanina/farmacologia , Feminino , Ácido Fólico/química , Humanos , Imunossupressores/farmacologia , Nanopartículas/química , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Telomerase/genética , Células Tumorais Cultivadas
18.
F1000Res ; 10: 127, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33968364

RESUMO

Background: Coronavirus (CoV) is an emerging human pathogen causing severe acute respiratory syndrome (SARS) around the world. Earlier identification of biomarkers for SARS can facilitate detection and reduce the mortality rate of the disease. Thus, by integrated network analysis and structural modeling approach, we aimed to explore the potential drug targets and the candidate drugs for coronavirus medicated SARS. Methods: Differentially expression (DE) analysis of CoV infected host genes (HGs) expression profiles was conducted by using the Limma. Highly integrated DE-CoV-HGs were selected to construct the protein-protein interaction (PPI) network.  Results: Using the Walktrap algorithm highly interconnected modules include module 1 (202 nodes); module 2 (126 nodes) and module 3 (121 nodes) modules were retrieved from the PPI network. MYC, HDAC9, NCOA3, CEBPB, VEGFA, BCL3, SMAD3, SMURF1, KLHL12, CBL, ERBB4, and CRKL were identified as potential drug targets (PDTs), which are highly expressed in the human respiratory system after CoV infection. Functional terms growth factor receptor binding, c-type lectin receptor signaling, interleukin-1 mediated signaling, TAP dependent antigen processing and presentation of peptide antigen via MHC class I, stimulatory T cell receptor signaling, and innate immune response signaling pathways, signal transduction and cytokine immune signaling pathways were enriched in the modules. Protein-protein docking results demonstrated the strong binding affinity (-314.57 kcal/mol) of the ERBB4-3cLpro complex which was selected as a drug target. In addition, molecular dynamics simulations indicated the structural stability and flexibility of the ERBB4-3cLpro complex. Further, Wortmannin was proposed as a candidate drug to ERBB4 to control SARS-CoV-2 pathogenesis through inhibit receptor tyrosine kinase-dependent macropinocytosis, MAPK signaling, and NF-kb singling pathways that regulate host cell entry, replication, and modulation of the host immune system. Conclusion: We conclude that CoV drug target "ERBB4" and candidate drug "Wortmannin" provide insights on the possible personalized therapeutics for emerging COVID-19.


Assuntos
COVID-19 , Preparações Farmacêuticas , Proteínas Adaptadoras de Transdução de Sinal , Humanos , Coativador 3 de Receptor Nuclear , Ligação Proteica , Mapas de Interação de Proteínas , SARS-CoV-2 , Ubiquitina-Proteína Ligases
19.
Med Oncol ; 38(4): 38, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33721131

RESUMO

Non-visual arrestins (ß-arrestins) are endocytic proteins that mediate agonist-activated GPCRs internalization and signaling pathways in an independent manner. The involvement of ß-arrestins in cancer invasion and metastasis is increasingly reported. So, it is hypothesized that inhibition of ß-arrestins may diminish the survival chances of cancer cells. This study aimed to evaluate the in vitro impact of inhibiting ß-arrestins on the autophagic and/or apoptotic responsiveness of breast cancer cells. We used Barbadin to selectively inhibit ß-Arr/AP2 interaction in AVP-stimulated V2R receptor of triple-negative breast cancer cells (MDA MB-231). Autophagy was assessed by the microtubule-associated protein 1 light chain 3-II (LC3II), apoptosis was measured by Annexin-V/PI staining and cell cycle distribution was investigated based upon the DNA content using flow cytometry. Barbadin reduced cell viability to 69.1% and increased the autophagy marker LC3II and its autophagic effect disappeared in cells transiently starved in Earle's balanced salt solution (EBSS). Also, Barbadin mildly enhanced the expression of P62 mRNA and arrested 63.7% of cells in G0/G1 phase. In parallel, the drug-induced apoptosis in 29.9% of cells (by AV/PI) and 27.8% of cells were trapped in sub-G1 phase. The apoptotic effect of Barbadin was enhanced when autophagy was inhibited by the PI3K inhibitor (Wortmannin). Conclusively, the data demonstrate the dual autophagic and apoptotic effects of ß-ßArr/AP2 inhibition in triple-negative breast cancer cells. These observations nominate ß-Arrs as selective targets in breast cancer treatment.


Assuntos
Apoptose , Autofagia , Pontos de Checagem da Fase G1 do Ciclo Celular , Receptores de Vasopressinas/metabolismo , beta-Arrestinas/antagonistas & inibidores , Complexo 2 de Proteínas Adaptadoras/metabolismo , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Pirimidinas/farmacologia , Receptores de Vasopressinas/agonistas , Transdução de Sinais/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , beta-Arrestinas/genética , beta-Arrestinas/metabolismo
20.
Front Pharmacol ; 12: 566470, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33762932

RESUMO

Ischemia-reperfusion (I/R) injury is an unavoidable injury that occurs during revascularization procedures. In the previous study, we reported that fisetin is a natural flavonoid that attenuates I/R injury by suppressing mitochondrial oxidative stress and mitochondrial dysfunction. Though fisetin is reported as a GSK3ß inhibitor, it remains unclear whether it attenuates myocardial ischemia by activating the phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) pathway, thereby inhibiting the downstream GSK3ß, or by directly interacting with GSK3ß while rendering its cardioprotection. In this study, the research team investigates the possible mechanism of action of fisetin while rendering its cardioprotective effect against myocardial I/R injury in rats. For this investigation, the team utilized two myocardial I/R models: Ligation of the left anterior descending artery and Langendorff isolated heart perfusion system. The latter has no neurohormonal influences. The PI3K inhibitor (Wortmannin, 0.015 mg/kg), GSK3ß inhibitor (SB216763, 0.7 mg/kg), and fisetin (20 mg/kg) were administered intraperitoneally before inducing myocardial I/R. The result of this study reveals that the administration of fisetin decreases the myocardial infarct size, apoptosis, lactate dehydrogenase, and creatine kinase in serum\perfusate of the rat hearts subjected to I/R. However, the inhibition of PI3K with Wortmannin significantly reduced the cardioprotective effect of fisetin both in the ex vivo and vivo models. The administration of GSK3ß inhibitor after the administration of fisetin and Wortmannin, re-establishing the cardioprotection, indicates the major role of PI3K in fisetin action. Changes in myocardial oxidative stress (level) and mitochondrial functional preservation of interfibrillar and subsarcolemmal mitochondria support the above findings. Hence, the team here reports that fisetin conferred its cardioprotection against I/R injury by activating the PI3K/Akt/GSK3ß signaling pathway in rat hearts.

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