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1.
Gut ; 69(1): 122-132, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31076405

RESUMO

OBJECTIVE: We investigated how pancreatic cancer developed resistance to focal adhesion kinase (FAK) inhibition over time. DESIGN: Pancreatic ductal adenocarcinoma (PDAC) tumours from KPC mice (p48-CRE; LSL-KRasG12D/wt; p53flox/wt) treated with FAK inhibitor were analysed for the activation of a compensatory survival pathway in resistant tumours. We identified pathways involved in the regulation of signal transducer and activator of transcription 3 (STAT3) signalling on FAK inhibition by gene set enrichment analysis and verified these outcomes by RNA interference studies. We also tested combinatorial approaches targeting FAK and STAT3 in syngeneic transplantable mouse models of PDAC and KPC mice. RESULTS: In KPC mice, the expression levels of phosphorylated STAT3 (pSTAT3) were increased in PDAC cells as they progressed on FAK inhibitor therapy. This progression corresponded to decreased collagen density, lowered numbers of SMA+ fibroblasts and downregulation of the transforming growth factor beta (TGF-ß)/SMAD signalling pathway in FAK inhibitor-treated PDAC tumours. Furthermore, TGF-ß production by fibroblasts in vitro drives repression of STAT3 signalling and enhanced responsiveness to FAK inhibitor therapy. Knockdown of SMAD3 in pancreatic cancer cells abolished the inhibitory effects of TGF-ß on pSTAT3. We further found that tumour-intrinsic STAT3 regulates the durability of the antiproliferative activity of FAK inhibitor, and combinatorial targeting of FAK and Janus kinase/STAT3 act synergistically to suppress pancreatic cancer progression in mouse models. CONCLUSION: Stromal depletion by FAK inhibitor therapy leads to eventual treatment resistance through the activation of STAT3 signalling. These data suggest that, similar to tumour-targeted therapies, resistance mechanisms to therapies targeting stromal desmoplasia may be critical to treatment durability.


Assuntos
Aminopiridinas/uso terapêutico , Antineoplásicos/uso terapêutico , Carcinoma Ductal Pancreático/tratamento farmacológico , Proteína-Tirosina Quinases de Adesão Focal/antagonistas & inibidores , Neoplasias Pancreáticas/tratamento farmacológico , Aminopiridinas/farmacologia , Animais , Antineoplásicos/farmacologia , Carcinoma Ductal Pancreático/enzimologia , Carcinoma Ductal Pancreático/patologia , Colágeno/metabolismo , Regulação para Baixo/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/fisiologia , Feminino , Fibroblastos/efeitos dos fármacos , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Humanos , Camundongos Endogâmicos , Neoplasias Pancreáticas/enzimologia , Neoplasias Pancreáticas/patologia , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína Smad3/metabolismo , Células Estromais/efeitos dos fármacos , Células Estromais/patologia , Fator de Crescimento Transformador beta/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Chemosphere ; 238: 124602, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31545211

RESUMO

Polybrominated diphenyl ethers (PBDEs) have been known to exhibit neurotoxicity in rats; however, the underlying mechanism remains unknown and there is no available intervention. In this study, we aimed to investigate the role of oxidative and nitrosative stress in the neurotoxicity in the cerebral cortex and primary neurons in rats following the BDE-153 treatment. Compared to the untreated group, BDE-153 treatment significantly induced the neurotoxic effects in rats, as manifested by the increased lactate dehydrogenase (LDH) activities and cell apoptosis rates, and the decreased neurotrophic factor contents and cholinergic enzyme activities in rats' cerebral cortices and primary neurons. When compared to the untreated group, the oxidative and nitrosative stress had occurred in the cerebral cortex or primary neurons in rats following the BDE-153 treatment, as manifested by the increments in levels of reactive oxygenspecies (ROS), malondialdehyde (MDA), nitric oxide (NO), and neuronal nitric oxide synthase (nNOS) mRNA and protein expressions, along with the decline in levels of superoxide dismutase (SOD) activity, glutathione (GSH) content, and peroxiredoxin I (Prx I) and Prx II mRNA and protein expressions. In addition, the ROS scavenger N-acetyl-l-cysteine (NAC) or NO scavenger NG-Nitro-l-arginine (L-NNA) significantly rescued the LDH leakage and cell survival, reversed the neurotrophin contents and cholinergic enzymes, mainly via regaining balance between oxidation/nitrosation and antioxidation. Overall, our findings suggested that oxidative and nitrosative stresses are involved in the neurotoxicity induced by BDE-153, and that the antioxidation is a potential targeted intervention.


Assuntos
Córtex Cerebral/patologia , Éteres Difenil Halogenados/toxicidade , Síndromes Neurotóxicas/patologia , Estresse Nitrosativo/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Bifenil Polibromatos/toxicidade , Acetilcisteína/farmacologia , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Glutationa/metabolismo , Éteres Difenil Halogenados/metabolismo , Masculino , Malondialdeído/metabolismo , Fatores de Crescimento Neural/metabolismo , Neurônios/efeitos dos fármacos , Neurotrofina 3/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Estresse Nitrosativo/fisiologia , Estresse Oxidativo/fisiologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
3.
APMIS ; 128(1): 10-19, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31642122

RESUMO

Atherogenesis is associated with chronic gut infections; however, the mechanisms are not clear. The aim of the study was to determine whether lipopolysaccharide of E. coli (E. coli LPS) may affect endothelial barrier and modify IL-10 expression in dendritic cells (DCs). Human umbilical vein endothelial cells (HUVECs) and monocyte-derived DCs were treated with E. coli LPS, apolipoprotein B100 (ApoB100) and 7-ketocholesterol (7-kCH) - harmful oxidized form of cholesterol. The effect of E. coli LPS, 7-kCH and ApoB100 on the barrier functions of HUVECs in real-time cell electric impedance sensing system (RTCA-DP) was assessed. Furthermore, the effect of 7-kCH and ApoB100 on barrier functions of HUVECs co-cultured with DCs previously treated with LPS was analyzed. Both E. coli LPS and 7-kCH decreased barrier functions of HUVECs and reduced tight junction protein mRNA expression, whereas ApoB100 increased endothelial barrier. In DCs, ApoB100 and E. coli LPS decreased IL-10 mRNA expression. In HUVECs co-cultured with DCs treated with LPS and subsequently pulsed with ApoB100 or 7-kCH, IL-10 mRNA expression was lower. E. coli LPS-exposed DCs diminished the protective effect of ApoB100 on endothelial integrity and led to the decrease in occludin mRNA expression. LPS potentially derived from gut microflora may destabilize endothelial barrier together with oxidized cholesterol and intensify the immunogenicity of ApoB100.


Assuntos
Células Dendríticas/efeitos dos fármacos , Escherichia coli/imunologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Interleucina-10/genética , Lipopolissacarídeos/imunologia , Junções Íntimas/efeitos dos fármacos , Apolipoproteína B-100/farmacologia , Células Cultivadas , Técnicas de Cocultura , Células Dendríticas/imunologia , Escherichia coli/química , Humanos , Cetocolesteróis/farmacologia , Lipopolissacarídeos/farmacologia , Ocludina/genética , Transdução de Sinais/efeitos dos fármacos , Proteínas de Junções Íntimas/genética
5.
J Photochem Photobiol B ; 201: 111657, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31706085

RESUMO

Parkinson's disease (PD) is a general neurodegenerative disorder which largely has an effect on the society of the aged populations. PD is distinguishedwith loss of dopaminergic (DA) neurons in the substantia nigra. The exceptional properties of gold nanoparticles (AuNPs) have fascinated great attention in biomedical applications. In this present study, we explored theprospective beneficial effects of AuNPs synthesized from Cinnamomum verum on PD. PD rat models were established through MPTP injection treatment and AuNPs was administered. Administration of AuNPs reduces effect of MPTP-induced oxidative stress and motor abnormalities observed in PD rats. In addition ELISA analysis demonstrated that AuNPs treatment significantly attenuates Tumor Necrosis Factor-α (TNF-α), Interleukin-1ß (IL-1ß) and Interleukin-6 (IL-6) expression levels. Consequently, we investigated TLR/NF-κB pathway to examine the function of AuNPs on MPTP- induced PD rats. We found that AuNPs suppressed the alterations in the pathway of TLR/NF-κB associated molecules in MPTP stimulated PD rats. Hence, our results suggest that AuNPs attenuates MPTP introduced motor disorders, oxidative stress, activated inflammatory cytokines and activated TLR/NF-κB signaling in PD rats. In conclusion, AuNPs ease PD symptoms by the inhibition of TLR/NF-κB signaling pathway and recommend promise approach in the treatment of neurodegenerative diseases such as PD.


Assuntos
Cinnamomum zeylanicum/química , Ouro/química , Intoxicação por MPTP/tratamento farmacológico , Nanopartículas Metálicas/uso terapêutico , Animais , Cinnamomum zeylanicum/metabolismo , Citocinas/metabolismo , Química Verde , Intoxicação por MPTP/patologia , Masculino , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Camundongos , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Receptores Toll-Like/metabolismo
6.
Adv Exp Med Biol ; 1163: 187-223, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31707705

RESUMO

Computational studies of allosteric interactions have witnessed a recent renaissance fueled by the growing interest in modeling of the complex molecular assemblies and biological networks. Allosteric interactions in protein structures allow for molecular communication in signal transduction networks. In this chapter, we discuss recent developments in understanding of allosteric mechanisms and interactions of protein systems, particularly in the context of structural, functional, and computational studies of allosteric inhibitors and activators. Computational and experimental approaches and advances in understanding allosteric regulatory mechanisms are reviewed to provide a systematic and critical view of the current progress in the development of allosteric modulators and highlight most challenging questions in the field. The abundance and diversity of genetic, structural, and biochemical data underlies the complexity of mechanisms by which targeted and personalized drugs can combat mutational profiles in protein kinases. Structural and computational studies of protein kinases have generated in recent decade significant insights that allowed leveraging knowledge about conformational diversity and allosteric regulation of protein kinases in the design and discovery of novel kinase drugs. We discuss recent developments in understanding multilayered allosteric regulatory machinery of protein kinases and provide a systematic view of the current state in understanding molecular basis of allostery mediated by kinase inhibitors and activators. In conclusion, we highlight the current status and future prospects of computational biology approaches in bridging the basic science of protein kinases with the discovery of anticancer therapies.


Assuntos
Regulação Alostérica , Biologia Computacional , Mapas de Interação de Proteínas , Inibidores de Proteínas Quinases , Proteínas Quinases , Transdução de Sinais , Regulação Alostérica/efeitos dos fármacos , Simulação de Dinâmica Molecular , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos
7.
Adv Exp Med Biol ; 1163: 279-311, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31707708

RESUMO

Allostery is a basic principle that enables proteins to process and transmit cellular information. Protein kinases evolved allosteric mechanisms to transduce cellular signals to downstream signalling components or effector molecules. Protein kinases catalyse the transfer of the terminal phosphate from ATP to protein substrates upon specific stimuli. Protein kinases are targets for the development of small molecule inhibitors for the treatment of human diseases. Drug development has focussed on ATP-binding site, while there is increase interest in the development of drugs targeting alternative sites, i.e. allosteric sites. Here, we review the mechanism of regulation of protein kinases, which often involve the allosteric modulation of the ATP-binding site, enhancing or inhibiting activity. We exemplify the molecular mechanism of allostery in protein kinases downstream of PI3-kinase signalling with a focus on phosphoinositide-dependent protein kinase 1 (PDK1), a model kinase where small compounds can allosterically modulate the conformation of the kinase bidirectionally.


Assuntos
Desenvolvimento de Medicamentos , Fosfatidilinositol 3-Quinases , Proteínas Quinases , Transdução de Sinais , Regulação Alostérica , Sítio Alostérico , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Ligação Proteica/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos
8.
J Agric Food Chem ; 67(46): 12844-12853, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31668063

RESUMO

Flazin is a ß-carboline-derived alkaloid found in Japanese fermented foods. Here, the potential of flazin as an antioxidant food was studied with particular reference to its effect on the Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2) system in human hepatocytes (C3A). Flazin and flazin analogues including the decarboxylated derivative perlolyrine were chemically synthesized and compared with each other and with chlorogenic acid and curcumin. Among these compounds, flazin showed the lowest cytotoxicity (IC50 < 500 µM) and the highest capacity to activate the Keap1-Nrf2 system. It provided the largest (>3-fold of the control) cytoprotection ability against a pro-oxidant, although its radical absorbance capacity was relatively low. Flazin increased the expressions of Nrf2-dependent phase II enzyme genes and their products (NQO1, GSTP, and GSH proteins). The strong cytoprotection ability of flazin associated with low log P (0-3) is shared by sulforaphane and 3,5-dihydroxy-4-methoxybenzyl alcohol, suggesting the potential value of flazin and flazin-rich foods for the prevention of oxidation-related health disorders.


Assuntos
Carbolinas/farmacologia , Furanos/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/genética , Transdução de Sinais/efeitos dos fármacos
9.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 35(4): 312-316, 2019 Jul 28.
Artigo em Chinês | MEDLINE | ID: mdl-31701713

RESUMO

OBJECTIVE: To investigate the effects and molecular mechanisms of 2-12alkyl-6-methoxycyclohexa-2,5-diene-1,4-dione(DMDD) on diffuse large B lymphoma (DLBCL). METHODS: In animal experiments, 4-week-aged BALB/C mice were divided into 5 groups, 20 mice in each group. Mice were inguinal injected with DLBCL cell line OCI-LY19 cells 0.1 ml at the concention of 1 × 107 /ml. Two days later, mice were treated with DMDD at the doses of 0, 1, 5, 25 and 125 mg/kg by intragastric administration respectively, once /2 days. Ten mice of each group were killed on the 18th day of administration, and the tumor tissues were weighed. The survival time of the remaining mice were recorded. In cell experiments, OCI-LY19 cells were added to 96-well culture plates, 100 µl 1×105 cells/ml per well, then 100 µl DMDD was added to the well and the final concentrations were 0, 1, 5, 25 and 125 µmol/L respectively. The cells were treated with DMDD for 0, 24, 48 and 72 h, three wells in each group. The cell proliferation activity was detected by MTS assay. According to the results of cell proliferation experiments, OCI-LY19 cells were treated with DMDD at the concentrations of 0 µmol/L, 5 µmol/L and 25 µmol/L for 24 h. The apoptosis rate was analyzed by flow cytometry, the nuclear type was observed by hoechst staining, the mitochondrial membrane potential was observed by JC-1 staining, cytotoxicity of drugs was evaluated by LDH release experiment, gene expression and transcription were analyzed by qPCR and Western blot. RESULTS: Compared with 0 mg/kg drug group, DMDD at the dose of 1~125 mg/kg could inhibit the growth of tumor tissue in mice and prolong their survival time (P<0.01). Cell experiments showed: in DMDD group, the proliferation activity of OCI-LY19 cells was decreased significantly and the level of apoptosis was increased significantly (P<0.01), nuclear fragmentation, agglutination, apoptotic bodies occurred and mitochondrial membrane potential was decreased, the LDH release rate was increased significantly (P<0.01), the expressions of caspase-3 and bax genes and the phosphorylation level of Ikappa B alpha in cells were up-regulated significantly, the protein expression levels of bcl-2, bcl-xL, jak2 and stat3 were inhibited significantly (P<0.01). CONCLUSION: DMDD can inhibit the expressions of JAK2, STAT3 and p-Ikappa B alpha in JAK2/STAT3 and NF-kappa B signal pathways, down-regulate BCL-2/BAX and activate Caspase-3, finally, activate the endogenous pathway of mitochondrial apoptosis in OCI-LY19 cells and promote the apoptosis of DLBCL cells, inhibit proliferation of OCI-LY19 cells. It has inhibitive effects on DLBCL.


Assuntos
Apoptose , Cicloexenos/farmacologia , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Proliferação de Células , Linfoma Difuso de Grandes Células B/patologia , Camundongos , Camundongos Endogâmicos BALB C
10.
Adv Exp Med Biol ; 1182: 263-269, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31777023

RESUMO

The anti-osteoporosis effect of Ganoderma lucidum (G. lucidum, Lingzhi) is closely associated with inhibition of osteoclastogenesis in the charge of osteoclasts. This article reviewed the anti-osteoporosis effect of Ganoderma and its active components, including a kind of triterpenoids, a polysaccharide and a protein named Ling Zhi-8 (LZ-8). Triterpenoids are a kind of active compounds as candidates for the treatment of osteoporosis. Among these, ganoderic acids are currently considered as the most important and potential components, and their structure-activity relationship highlights the essential group to hamper osteoclast differentiation. The data confirmed that the active compounds isolated from triterpenoids and meroterpenoids could suppress bone resorption of osteoclast via RANKL/RANK pathway and/or its downstream signaling transduction related to ERK, JNK and p38 MAPKs, contributing to inhibition of the level of c-Fos and NFATc1, two key target genes of osteoclast for osteoclastogenesis. However, the comprehensive mechanism remains to be elucidated in the future.


Assuntos
Produtos Biológicos/farmacologia , Osteogênese/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Reishi/química , Diferenciação Celular , Humanos , Osteoclastos/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
11.
J Environ Pathol Toxicol Oncol ; 38(2): 133-141, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31679276

RESUMO

The current study is a review of the literature on patients with diabetes who are diagnosed with colorectal cancer (CRC), encompassing recent research on CRC and the molecular level changes occurring in these patients on the basis of varying environmental as well as non-environmental factors. It has been noted that nearly 50% of all patients undergo the systemic treatment module; however, most of them exhibit drug resistance. In addition, targeted gene therapy has also been used in treatment but has been found to be effective only in patients with a specified molecular profile (or else this might lead to an increased risk of developing resistant mutations). This has led to increasing interest among researchers in finding innovative treatment options. Metformin, a biguanide, has been widely used in treating diabetes. The drug has been reportedly used in cases of hypothesis-generating retrospective population studies of diabetic patients showing reduced incidence of cancer. Metformin helps in reduction of excess insulin levels that possess various effects on cell signaling and metabolism. Nonetheless, there is need for an in-depth study on its molecular mechanism to fill any existing research gaps.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Neoplasias Colorretais/complicações , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Humanos , Insulina/efeitos adversos , Transdução de Sinais/efeitos dos fármacos
12.
J Environ Pathol Toxicol Oncol ; 38(3): 239-251, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31679311

RESUMO

Fucoxanthin, a potent carotenoid present in various natural sources especially from seaweeds; it exhibits several biological effects like anti-neoplastic, anti-mutagenic, anti-diabetic, anti-obesity and anti-inflammatory actions. Fucoxanthin role in chemoprevention of lung cancer in mouse model induced using benzo(a)pyrene [B(a)P] has been presented here. Oral administration of fucoxanthin with and without B(a)P were studied, the results from our study shows that fucoxanthin significantly decreased tumor progression in mice exposed to B(a)P, the obtained data were correlated with increased antioxidant, apoptosis and decreased tumour marker and anti-apoptotic molecules. With respect to apoptosis, fucoxanthin treated animals shows increased apoptosis compared to tumor induced mice by increased expression of caspase 9 and 3 and decreased expression of anti-apoptotic Bcl2 protein. Finally, histopathological and immuno histochemical analysis also revealed that fucoxanthin shows potent anticancer agent by bringing back the damaged tissue treated with B(a)P and also decreases the expression of PCNA in cancer induced mice. The anticancer effect of fucoxanthin may be attributed by several independent mechanisms which play a important roles in the prevention of cancer development, there is also substantial evidences to show that fucoxanthin acts indirectly by increasing the antioxidant capacity of affected tissue and prepared to cope up with oxidative stress which is proved in our study. Thus from our study it is clearly established that fucoxanthin act as a persuasive anticancer drug against lung cancer.


Assuntos
Anti-Inflamatórios/farmacologia , Apoptose/imunologia , Inflamação/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Transdução de Sinais/imunologia , Xantofilas/farmacologia , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Benzo(a)pireno/toxicidade , Inflamação/induzido quimicamente , Masculino , Camundongos , Transdução de Sinais/efeitos dos fármacos
13.
Cell Physiol Biochem ; 53(5): 865-886, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31724838

RESUMO

BACKGROUND/AIMS: Heart failure is characterized by chronic low-grade vascular inflammation, which in itself can lead to endothelial dysfunction. Clinical trials showed reductions in heart failure-related hospitalizations of type 2 diabetic patients using sodium glucose co-transporter 2 inhibitors (SGLT2i's). Whether and how SGLT2i's directly affect the endothelium under inflammatory conditions is not completely understood. The aim of the study was to investigate whether the SGLT2i Empagliflozin (EMPA) and Dapagliflozin (DAPA) reduce tumor necrosis factor α (TNFα) induced endothelial inflammation in vitro. METHODS: Human coronary arterial endothelial cells (HCAECs) and human umbilical vein endothelial cells (HUVECs) were (pre-)incubated with 1 µM EMPA or DAPA and subsequently exposed to 10 ng/ml TNFα. ROS and NO were measured using live cell imaging. Target proteins were either determined by infrared western blotting or fluorescence activated cell sorting (FACS). The connection between Cav-1 and eNOS was determined by co-immunoprecipitation. RESULTS: Nitric oxide (NO) bioavailability was reduced by TNFα and both EMPA and DAPA restored NO levels in TNFα-stimulated HCAECs. Intracellular ROS was increased by TNFα, and this increase was completely abolished by EMPA and DAPA in HCAECs by means of live cell imaging. eNOS signaling was significantly disturbed after 24 h when cells were exposed to TNFα for 24h, yet the presence of both SGLT2is did not prevent this disruption. TNFα-induced enhanced permeability at t=24h was unaffected in HUVECs by EMPA. Similarly, adhesion molecule expression (VCAM-1 and ICAM-1) was elevated after 4h TNFα (1.5-5.5 fold increase of VCAM-1 and 4-12 fold increase of ICAM-1) but were unaffected by EMPA and DAPA in both cell types. Although we detected expression of SGLT2 protein levels, the fact that we could not silence this expression by means of siRNA and the mRNA levels of SGLT2 were not detectable in HCAECs, suggests aspecificity or our SGLT2 antibody and absence of SGLT2 in our cells. CONCLUSION: These data suggest that EMPA and DAPA rather restore NO bioavailability by inhibiting ROS generation than by affecting eNOS expression or signaling, barrier function and adhesion molecules expression in TNFα-induced endothelial cells. Furthermore, the observed effects cannot be ascribed to the inhibition of SGLT2 in endothelial cells.


Assuntos
Compostos Benzidrílicos/farmacologia , Regulação para Baixo/efeitos dos fármacos , Glucosídeos/farmacologia , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Vasos Coronários/citologia , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Permeabilidade/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Transportador 2 de Glucose-Sódio/genética , Transportador 2 de Glucose-Sódio/metabolismo , Molécula 1 de Adesão de Célula Vascular
14.
Chem Biol Interact ; 314: 108843, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31586550

RESUMO

Depression is a common neuropsychiatric disorder whose pathophysiology has been associated with glutamatergic excitotoxicity. Thus, the research for new antidepressant strategies with the ability to mitigate glutamate toxicity has received growing attention. Given this background, the present study sought to investigate the antidepressant-like and neuroprotective effects of Morus nigra (MN) and its major phenolic, syringic acid (SA), against glutamate-induced damage, as well as, the role of the PI3K/Akt/GSK-3ß signaling pathway in these effects. Treatment with MN (3 mg/kg) and SA (1 mg/kg) for 7 days, similar to fluoxetine (10 mg/kg), triggered an antidepressant-like effect. Moreover, the treatments evoked neuroprotection against glutamatergic excitotoxicity in hippocampal slices, and MN treatment also afforded protection in cerebrocortical slices. Notably, ex vivo neuroprotective effect of MN and SA was mediated, at least in part, by PI3K/Akt/GSK-3ß signaling pathway. Furthermore, the ability of MN and SA to counteract the glutamate-induced damage were evaluated in three different in vitro experiments. The hippocampal slices pretreated with MN (0.05 and 0.1 µg/mL) or SA (0.01-0.1 µg/mL) as well as the concomitant treatment with MN (0.01 and 0.05 µg/mL) or SA (0.05 and 0.1 µg/mL) exhibited protection against glutamate toxicity. Interestingly, post-treatment with MN in all doses (0.01-0.1 µg/mL) and SA at dose of 0.1 µg/mL were capable of preventing glutamate-induced cell death. In vitro neuroprotective effect of SA, but not MN, involves the activation of Akt, since the pretreatment with LY294002 completely abolished the protective effect. Overall, MN and SA presented antidepressant-like and neuroprotective effects against glutamatergic excitotoxicity via PI3K/Akt/GSK-3ß.


Assuntos
Antidepressivos/farmacologia , Ácido Gálico/análogos & derivados , Morus/química , Fármacos Neuroprotetores/farmacologia , Fenóis/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Antidepressivos/isolamento & purificação , Comportamento Animal/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Ácido Gálico/isolamento & purificação , Ácido Gálico/farmacologia , Ácido Glutâmico/farmacologia , Glicogênio Sintase Quinase 3 beta/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Camundongos , Morus/metabolismo , Fármacos Neuroprotetores/isolamento & purificação , Fenóis/isolamento & purificação , Fosfatidilinositol 3-Quinases/metabolismo , Extratos Vegetais/química , Proteínas Proto-Oncogênicas c-akt/metabolismo
15.
J Agric Food Chem ; 67(44): 12191-12198, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31588747

RESUMO

Fermented black garlic has multiple beneficial biological activities, including cardiovascular protection, anticancer, hepatoprotective, and antibacterial properties. In this study, metabolic differences in the properties of black and fresh garlic were investigated via liquid chromatography quadrupole/time-of-flight-based metabolomics, leading to the identification of characteristic components. Fermented black garlic samples and their Amadori products (AC) promoted angiogenesis, prevented thrombus formation by rescuing chemical-induced vascular lesions in zebrafish, and inhibited H2O2-induced injury of endothelial cells, thus reducing the risk of cardiovascular disease. AC suppressed activation of the mitogen-activated protein kinase pathway through inhibition of p38 and ERK1/2 phosphorylation, in turn, increasing the availability of c-Fos/c-Jun or c-Jun/c-Jun complexes for apoptotic resistance. Clarification of the associated signaling pathways should therefore provide a solid foundation for optimization of black garlic-based therapies.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Alho/química , Extratos Vegetais/administração & dosagem , Animais , Biomarcadores/análise , Biomarcadores/metabolismo , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Feminino , /análise , Humanos , Peróxido de Hidrogênio/toxicidade , Masculino , Espectrometria de Massas , Metabolômica , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Extratos Vegetais/química , Transdução de Sinais/efeitos dos fármacos , Peixe-Zebra
16.
Cell Physiol Biochem ; 53(4): 701-712, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31592599

RESUMO

BACKGROUND/AIMS: Cholinergic signalling mediated by the activation of muscarinic and nicotinic receptors has been described in the literature as a classic and important signalling pathway in the regulation of the inflammatory response. Recent research has investigated the role of acetylcholine, the physiological agonist of these receptors, in the control of energy homeostasis at the central level. Studies have shown that mice that do not express acetylcholine in brain regions regulating energy homeostasis present with excessive weight gain and hyperphagia. However, it has not yet been well-described in the literature which cholinergic receptor subunits are involved in this response; moreover, the signalling pathways responsible for the observed effects are not fully delineated. The hypothalamus is the regulating centre of energy homeostasis, and the α7 subunit of the nicotinic acetylcholine receptor (α7nAChR) is highly expressed in this region. When active, α7nAChR recruits proteins such as JAK2/STAT3 to mediate its signalling; the same intracellular components are required by leptin, an anorexigenic hormone. The aim of the present study was to evaluate the role of the hypothalamic α7nAChR in the control of energy homeostasis. METHODS: The work was performed on Swiss male mice. Initially, using immunofluorescent staining on brain sections, the presence of α7nAChR in hypothalamic cells regulating energy homeostasis was evaluated. Animals were submitted to stereotaxis in the lateral ventricle and intracerebroventricular stimulation (ICV) was used for the administration of an agonist (PNU) or antagonist (α-bungarotoxin) of α7nAChR. Metabolic parameters were evaluated and the expression of neuropeptides was evaluated in the hypothalamus by real-time PCR and western blot. The expression of hypothalamic neuropeptides was evaluated in mice treated with siRNA or inhibitors of JAK2/STAT3 (AG490 and STATTIC) proteins. We also evaluated food intake in α7nAChR knockout animals (α7KO). Additionally, in mouse hypothalamic cell culture (the mypHoA-POMC/GFP lineage), we evaluated the expression of neuropeptides and pSTAT3 after stimulation with PNU. RESULTS: Our results indicate co-localisation of α7nAChR with α-MSH, AgRP and NPY in hypothalamic cells. Pharmacological activation of α7nAChR reduced food intake and increased hypothalamic POMC expression and decreased NPY and AgRP mRNA levels and the protein content of pAMPK. Inhibition of α7nAChR with an antagonist increased the mRNA content of NPY and AgRP. Inhibition of α7nAChR with siRNA led to the suppression of POMC expression and an increase in AgRP mRNA levels. α7KO mice showed no changes in food intake. Inhibition of proteins involved in the JAK2/STAT3 signalling pathway reversed the effects observed after PNU stimulation. POMC-GFP cells, when treated with PNU, showed increased POMC expression and nuclear translocation of pSTAT3. CONCLUSION: Thus, selective activation of α7nAChR is able to modulate important markers of the response to food intake, suggesting that α7nAChR activation can suppress the expression of orexigenic markers and favour the expression of anorexics using the intracellular JAK2/STAT3 machinery.


Assuntos
Proteína Relacionada com Agouti/metabolismo , Janus Quinase 2/metabolismo , Pró-Opiomelanocortina/metabolismo , Fator de Transcrição STAT3/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Proteína Relacionada com Agouti/genética , Animais , Benzamidas/farmacologia , Compostos Bicíclicos com Pontes/farmacologia , Bungarotoxinas/farmacologia , Linhagem Celular , Ingestão de Alimentos/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Janus Quinase 2/antagonistas & inibidores , Janus Quinase 2/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/metabolismo , Pró-Opiomelanocortina/genética , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/genética , Transdução de Sinais/efeitos dos fármacos , Receptor Nicotínico de Acetilcolina alfa7/agonistas , Receptor Nicotínico de Acetilcolina alfa7/antagonistas & inibidores , Receptor Nicotínico de Acetilcolina alfa7/genética
17.
Chem Biol Interact ; 314: 108846, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31606474

RESUMO

Matrix metalloproteinases (MMPs) have been implicated in EMT but their role in the regulation of cigarette smoke-induced EMT in airway epithelium is not clear. We have therefore investigated the potential role of MMP-2 and -9 in cigarette smoke extract (CSE) induced EMT using A549 lung epithelial cells and human small airway epithelial cells (SAEC). The cells were treated with different concentration of CSE, and MTT and trypan blue assays, acridine orange-ethidium bromide assay, gelatin zymography, Western blotting, immunofluorescence studies, Boyden-chamber assay, wound healing assay and air-liquid interface (ALI) culture were used to assess different cellular and molecular changes associated with EMT. The results depict that CSE increased the cytotoxicity along with a concurrent increase in the expression and activity of MMP-2 and -9. CSE further altered EMT markers like E-cadherin, N-cadherin, vimentin, and the molecular modulators of EMT such as ß-catenin and pGSK-3ß. Further, CSE also upregulated EGFR, AKT, and ERK1/2 in airway epithelial cells. SB-3CT, a known inhibitor of MMP-2 and -9, altered and reversed the expression of markers of EMT and kinases, validating the role of MMP-2 and -9 in CSE-induced EMT. Fisetin, a plant-derived bioflavonoid, also reversed the expression of EMT markers and molecular regulators in a similar fashion as SB-3CT. In summary, this study highlights the role of MMP-2 and -9 in CSE-induced EMT and curate its molecular cascade through EGFR/AKT/ERK/ß-catenin axis, which could be restored by MMP-2 and -9 inhibitor and fisetin. Fisetin is hitherto unknown to modulate CSE-induced MMPs activity in airway epithelial cells, and our study suggests its potential role as a therapeutic approach in CSE-induced EMT in lung epithelial cells.


Assuntos
Transição Epitelial-Mesenquimal/efeitos dos fármacos , Flavonoides/farmacologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fumaça/efeitos adversos , Tabaco/química , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Receptores ErbB/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , beta Catenina/metabolismo
18.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(5): 1402-1408, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31607290

RESUMO

OBJECTIVE: To investigate the mechanism of rapamycin-induced apoptosis of chronic myelogenous leukemia cells. METHODS: The chronic granulocytic leukemia K562 cells were divided into 3 groups: A, B and C group were treated with rapamycin of 10, 15 and 20 nmol/L, repectively for 24 h, while the K562 cells in control group were not treated with rapamycin. The effect of rapamycin on the proliferation of K562 cells was detected by MTT, and the effect of rapamycin on the apoptosis of K562 cells was detected by AnnexinV-FITC/PI double staining. The expression level of EZH2/Hedgehog signaling pathway genes in K562 cells was detected by RT-PCR, and Western blot was used to detect the levels of apoptotic protein and the related signaling pathway proteins in K562 cells. RESULTS: The MTT assay showed that the different concentration of rapamycin had obvious inhibitory effects on the cells, and the survival rate of cells in group C was 37.6%±3.4%, which was significantly lower than that of the other groups (P<0.05). The apoptosis rate of cells in group C was 93.1%±8.1%, which was significantly higher than that of the other groups (P<0.05). By Western blot, it was found that the relative expression levels of Caspase-3 and BAX protein in group C were 0.36 ± 0.04 and 0.39±0.06, respectively, which were significantly higher than those in other groups (P<0.05), and the level of BCL-2 protein was 0.17±0.03, which was significantly lower than that of other groups (P<0.05). By RT-PCR, it was found that the mRNA levels of EZH2 and Hedgehog genes in A, B and C groups were significantly lower than those in the control group (P<0.05), but mRNA level of Ptch1 gene was significantly higher than that of the control (P<0.05). By Western blot, it was found that the expression levels of EZH2 and Hedgehog protein in A, B and C groups were significantly lower than that in the control group (P<0.05), but the level of Ptch1 protein was higher than that of the control (P<0.05). The relative levels of EZH2 and Hedgehog protein in group C were 0.21 ±0.03 and 0.16±0.05 respectively, which were significantly lower than those in other groups (P<0.05), and Ptch1 protein level were 0.46 ±0.06, significantly higher than that of other groups (P<0.05). CONCLUSION: Rapamycin can inhibit the protein expression of EZH2 in leukemic cells, thus interfere with the activation of Hedgehog signaling pathway, promote the expression of apoptotic protein, reduce the level of anti apoptotic protein, and eventually induce apoptosis of leukemia cells.


Assuntos
Transdução de Sinais/efeitos dos fármacos , Apoptose , Proliferação de Células , Proteína Potenciadora do Homólogo 2 de Zeste , Proteínas Hedgehog , Humanos , Células K562 , Sirolimo
19.
J Cancer Res Clin Oncol ; 145(12): 2921-2936, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31620898

RESUMO

PURPOSE: The present study aims to determine whether co-targeting PI3K/Akt and MAPK/ERK pathways in human hypopharyngeal squamous cell carcinoma (HSCC) is a potential anticancer strategy. METHODS: We retrospectively analyzed the clinical data of HSCC patients, and the phosphorylation status of Akt and Erk in HSCC and tumor adjacent tissues was evaluated by immunohistochemistry. MTT and colony formation assay were performed to determine the anti-proliferative effect of PI3K/mTOR inhibitor GDC-0980 and MEK inhibitor Refametinib on HSCC cell line Fadu. Wound-healing and Transwell migration assay were used to analyze the anti-migrative capability of the two drugs. The involved anti-tumor mechanism was explored by flow cytometry, qRT-PCR and western blot. The combinational anticancer effect of GDC-0980 and Refametinib was evaluated according to Chou and Talalay's method. RESULTS: The levels of p-Akt and p-Erk were increased significantly with the progression of clinical stage of HSCC, suggesting PI3K/Akt and MAPK/ERK pathways might be associated with HSCC occurrence and progression. Furthermore, both GDC-0980 and Refametinib showed obvious antitumor effects on FaDu cells. Treatment by the two drugs arrested FaDu cell cycle progression in G1 phase, with reduction of cyclin D1 and p-Rb, in contrast to enhancement of p27. GDC-0980 inhibited FaDu cell migration and reduced metastasis related proteins including p-PKCζ, p-Integrin ß1 and uPA. Combination use of GDC-0980 and Refametinib exhibited strong synergistic anti-tumor effect. CONCLUSION: Dual inhibition of PI3K/Akt and MAPK/ERK pathway by GDC-0980 and Refametinib might be a promising treatment strategy for HSCC patients.


Assuntos
Antineoplásicos/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Neoplasias Hipofaríngeas/tratamento farmacológico , Neoplasias Hipofaríngeas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Difenilamina/análogos & derivados , Difenilamina/farmacologia , Sinergismo Farmacológico , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pirimidinas/farmacologia , Estudos Retrospectivos , Sulfonamidas/farmacologia
20.
Br J Anaesth ; 123(6): 827-838, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31623841

RESUMO

BACKGROUND: Spinal cord injury induces inflammatory responses that include the release of cytokines and the recruitment and activation of macrophages and microglia. Neuroinflammation at the lesion site contributes to secondary tissue injury and permanent locomotor dysfunction. Dexmedetomidine (DEX), a highly selective α2-adrenergic receptor agonist, is anti-inflammatory and neuroprotective in both preclinical and clinical trials. We investigated the effect of DEX on the microglial response, and histological and neurological outcomes in a rat model of cervical spinal cord injury. METHODS: Anaesthetised rats underwent unilateral (right) C5 spinal cord contusion (75 kdyne) using an impactor device. The locomotor function, injury size, and inflammatory responses were assessed. The effect of DEX was also studied in a microglial cell culture model. RESULTS: DEX significantly improved the ipsilateral upper-limb motor dysfunction (grooming and paw placement; P<0.0001 and P=0.0012), decreased the injury size (P<0.05), spared white matter (P<0.05), and reduced the number of activated macrophages (P<0.05) at the injury site 4 weeks post-SCI. In DEX-treated rats after injury, tissue RNA expression indicated a significant downregulation of pro-inflammatory markers (e.g. interleukin [IL]-1ß, tumour necrosis factor-α, interleukin (IL)-6, and CD11b) and an upregulation of anti-inflammatory and pro-resolving M2 responses (e.g. IL-4, arginase-1, and CD206) (P<0.05). In lipopolysaccharide-stimulated cultured microglia, DEX produced a similar inflammation-modulatory effect as was seen in spinal cord injury. The benefits of DEX on these outcomes were mostly reversed by an α2-adrenergic receptor antagonist. CONCLUSIONS: DEX significantly improves neurological outcomes and decreases tissue damage after spinal cord injury, which is associated with modulation of neuroinflammation and is partially mediated via α2-adrenergic receptor signaling.


Assuntos
Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Dexmedetomidina/farmacologia , Inflamação/tratamento farmacológico , Receptores Adrenérgicos alfa 2/efeitos dos fármacos , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/fisiopatologia , Animais , Células Cultivadas , Modelos Animais de Doenças , Feminino , Microglia/efeitos dos fármacos , Ratos , Ratos Long-Evans , Transdução de Sinais/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Medula Espinal/fisiopatologia
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