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1.
J Vis Exp ; (196)2023 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-37458427

RESUMO

Fu's subcutaneous needling (FSN), an invented acupuncture technique from traditional Chinese medicine, is used worldwide for pain relief. However, the mechanisms of action are still not fully understood. During FSN treatment, the FSN needle is inserted and retained in the subcutaneous tissues for a long duration with a swaying movement. However, challenges arise from maintaining a posture while manipulating FSN in animal models (e.g., rats) for researchers. Uncomfortable treatment can lead to fear and resistance to FSN needles, increasing the risk of injury and may even affect research data. Anesthesia may also affect the study results too. Hence, there is a need for strategies in FSN therapy on animals that minimize injury during the intervention. This study employs a chronic constriction injury model in Sprague-Dawley rats to induce neuropathic pain. This model replicates the pain induced by nerve injury observed in humans through surgical constriction of a peripheral nerve, mimicking the compression or entrapment seen in conditions such as nerve compression syndromes and peripheral neuropathies. We introduce an appropriate manipulation for easily inserting an FSN needle into the subcutaneous layer of the animal's body, including needle insertion and direction, needle retention, and swaying movement. Minimizing the rat's discomfort prevents the rat from being tense, which causes the muscle to contract and hinder the entry of the needle and improves the study efficiency.


Assuntos
Lesões por Esmagamento , Neuralgia , Humanos , Ratos , Animais , Tela Subcutânea , Constrição , Ratos Sprague-Dawley , Neuralgia/etiologia , Neuralgia/terapia , Nervo Isquiático
2.
J Cell Mol Med ; 27(11): 1539-1549, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37177859

RESUMO

Hepatocellular carcinoma (HCC) is recognized as the fifth most common cancer and the third most common cause of death in Asian population. Studies reported that HCC is relatively insensitive to radiotherapy (RT); thus, considering how to sensitize HCC to RT is worth to be elucidated. Epidermal growth factor receptor (EGFR)-mediated signalling transduction plays the important role in regulating treatment efficacy of HCC. An active compound, 18beta-glycyrrhetinic acid (18ß-GA), has been reported to own anti-tumour effect. However, whether 18ß-GA possess RT sensitization ability in HCC remains unclear. Here, we used RNA data from TCGA-LIHC (Liver hepatocellular carcinoma) to identify the role between EGFR/ERK/nuclear factor kappa B (NF-κB) signalling and RT by radiosensitivity index (RSI) analysis. We suggested that patients with activated NF-κB signalling may show resistance to RT treatment, whereas combining 18ß-GA may reinforce RT efficacy in a Hep3B-bearing animal model. 18ß-GA combined with RT showed superior tumour inhibition capacity as compared to monotherapy and even reached similar efficacy as erlotinib combined with RT. Treatment promotion of RT by 18ß-GA in HCC is not only through diminishing RT-induced EGFR/ERK/NF-κB signalling but also promoting RT-induced apoptosis pathways. 18ß-GA may act as radiosensitizer through inactivating EGFR-mediated HCC progression and inducing caspase-dependent apoptosis signalling.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Radiossensibilizantes , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/radioterapia , NF-kappa B/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/radioterapia , Radiossensibilizantes/farmacologia , Radiossensibilizantes/uso terapêutico , Receptores ErbB/genética
3.
Biomed Pharmacother ; 161: 114476, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36905808

RESUMO

BACKGROUND: Age-related macular degeneration is the leading cause of visual deficiency in older adults worldwide. Melatonin (MT) can potentially reduce retinal deterioration. However, the mechanism by which MT mediates regulatory T cells (Tregs) in the retina is not yet fully understood. METHODS: The transcriptome profiles of aged or young human retinal tissues from the GEO database were analyzed for MT-related gene expression. The pathological changes in the retina in the NaIO3-induced mouse model were quantitatively determined by staining with hematoxylin and eosin. Retinal whole-mounting immunofluorescence staining was conducted to determine the expression of the Treg-specific marker FOXP3. The phenotypes of M1/M2 macrophages were representing related gene markers in the retina. The GEO database includes biopsies from patients with retinal detachment for ENPTD1, NT5E, and TET2 gene expression. A pyrosequencing assay was performed for NT5E DNA methylation on human primary Tregs, and siTET2 transfection engineering was used. RESULTS: MT synthesis-related genes in retinal tissue may be affected by age. Our study shows that MT can effectively restore NaIO3-induced retinopathy and maintain retinal structural integrity. Importantly, MT may assist the conversion of M1 to M2 macrophages to promote tissue repair, which may be caused by the increased infiltration of Tregs. Moreover, MT treatment may upregulate TET2, and further NT5E demethylation is associated with Treg recruitment in the retinal microenvironment. CONCLUSIONS: Our findings suggest that MT can effectively ameliorate retinal degeneration and regulate immune homeostasis via Tregs. Modulation of the immune response may provide a key therapeutic strategy.


Assuntos
Degeneração Macular , Melatonina , Camundongos , Animais , Humanos , Idoso , Melatonina/farmacologia , Melatonina/metabolismo , Retina/patologia , Degeneração Macular/induzido quimicamente , Degeneração Macular/genética , Modelos Animais de Doenças , Homeostase , Epitélio Pigmentado da Retina
4.
Immunology ; 168(4): 654-670, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36314527

RESUMO

The prognosis of systemic lupus erythematosus (SLE) is unpredictable. This study aimed to examine the regulatory mechanism of the AHR/TET2/NT5E pathway during SLE progression. The AHR, TET2 and NT5E expression levels were examined in T regulatory cells (Tregs) of patients with SLE. The correlation of AHR, TET2 or NT5E expression levels with the immunosuppressive functions of Tregs was analysed. In patients with SLE, the number of CD4+ IL2RA- FOXP3+ T cell subset was positively correlated with the SLE disease activity index value and negatively correlated with the AHR and TET2 expression levels in CD4+ IL2RA+ FOXP3+ Tregs. Transcriptional profiles of 79 patients with SLE obtained from the Gene Expression Omnibus database (GSE61635 dataset) revealed a significant positive correlation between the mRNA expression levels of AHR and TET2. In silico analysis predicted that the TET2 promoter comprises an AHR-binding site. Kynurenine (KYN) promoted the binding of AHR to the TET2 promoter in Tregs of patients with SLE and Jurkat T cell lines. Furthermore, NT5E expression was significantly downregulated in Tregs of patients with SLE, which can be attributed to the dysregulation of NT5E promoter methylation status induced by downregulated TET2 activity. Furthermore, the Treg immunosuppressive activity, which is mediated through the TET2 and A2AR-adenosine pathways, in the KYN-treated group was approximately two-fold higher than that in the control group. The AHR/TET2/NT5E axis mediates the Treg immunosuppressive activity. These findings provide novel insights for the development of therapeutic approaches for SLE and related autoimmune diseases.


Assuntos
Dioxigenases , Lúpus Eritematoso Sistêmico , Humanos , 5'-Nucleotidase/genética , 5'-Nucleotidase/metabolismo , Dioxigenases/genética , Dioxigenases/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação para Baixo , Fatores de Transcrição Forkhead/metabolismo , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Subpopulações de Linfócitos T , Linfócitos T Reguladores
5.
Biomed Pharmacother ; 155: 113725, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36152407

RESUMO

Diabetic retinopathy (DR) is a pathophysiologic vasculopathic process with obscure mechanisms and limited effective therapeutic strategies. Aryl hydrocarbon receptor (AhR) is an important regulator of xenobiotic metabolism and an environmental sensor. The aim of the present study was to investigate the role of AhR in the development of DR and elucidate the molecular mechanism of its downregulation. DR was evaluated in diabetes-induced retinal injury in wild type and AhR knockout (AhR-/-) mice. Retinal expression of AhR was determined in human donor and mice eyes by immunofluorescence since AhR activity was examined in diabetes. AhR knockout (AhRKO) mice were used to induce diabetes with streptozotocin, high-fat diet, or genetic double knockout with diabetes spontaneous mutation (Leprdb) (DKO; AhR-/-×Leprdb/db) for investigating structural, functional, and metabolic abnormalities in vascular and epithelial retina. Structural molecular docking simulation was used to survey the pharmacologic AhR agonists targeting phosphorylated AhR (Tyr245). Compared to diabetic control mice, diabetic AhRKO mice had aggravated alterations in retinal vasculature that amplified hallmark features of DR like vasopermeability, vascular leakage, inflammation, blood-retinal barrier breakdown, capillary degeneration, and neovascularization. AhR agonists effectively inhibited inflammasome formation and promoted AhR activity in human retinal microvascular endothelial cells and pigment epithelial cells. AhR activity and protein expression was downregulated, resulting in a decrease in DNA promoter binding site of pigment epithelium-derived factor (PEDF) by gene regulation in transcriptional cascade. This was reversed by AhR agonists. Our study identified a novel of DR model that target the protective AhR/PEDF axis can potentially maintain retinal vascular homeostasis, providing opportunities to delay the development of DR.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Camundongos , Humanos , Animais , Retinopatia Diabética/tratamento farmacológico , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Estreptozocina/farmacologia , Células Endoteliais/metabolismo , Inflamassomos/metabolismo , Simulação de Acoplamento Molecular , Xenobióticos/metabolismo , Retina , Camundongos Endogâmicos C57BL , Diabetes Mellitus/metabolismo
6.
Front Synaptic Neurosci ; 14: 859278, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35685245

RESUMO

Hot compress modalities are used to ameliorate pain despite prevalent confusion about which modality should be used and when. Most recommendations for hot compresses are based on empirical experience, with limited evidence to support its efficacy. To obtain insight into the nerve transmission mechanism of hot compresses and to identify the nerve injury marker proteins specifically associated with sciatic nerve pain, we established a rat model of chronic constriction injury (CCI) and performed mechanical allodynia, electrophysiology, and histopathological analysis. All CCI rats exhibited geometric representation of the affected hind paw, which indicated a hyper-impact on both mechanical gait and asymmetry of gait on day 28. The CCI model after 28 days of surgery significantly reduced compound muscle action potential (CMAP) amplitude, but also significantly reduced latency. Administration of hot compress for 3 weeks (heated at 40-42°C, cycle of 40 min, and rest for 20 min, three cycles each time, three times per week) significantly increased the paw withdrawal thresholds in response to stimulation by Von Frey fibers and reversed the CCI-induced reduced sciatic functional index (SFI) scores. Hot compress treatment in the CCI model improved CMAP amplitude and latency. The S100 protein expression level in the CCI+Hot compression group was 1.5-fold higher than in the CCI group; it dramatically reduced inflammation, such as tumor necrosis factor alpha and CD68 expression in nerve injury sites. Synaptophysin (Syn) expression in the CCI+Hot compression group was less than threefold in the CCI group at both nerve injury sites and brain (somatosensory cortex and hippocampus). This finding indicates that local nerve damage and inflammation cause significant alterations in the sensorimotor strip, and hot compress treatment could significantly ameliorate sciatic nerve pain by attenuating Syn and inflammatory factors from local pathological nerves to the brain. This study determines the potential efficacy and safety of hot compress, and may have important implications for its widespread use in sciatic nerve pain treatment.

7.
Phytomedicine ; 95: 153876, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34923233

RESUMO

BACKGROUND: In traditional Chinese medicine, the skin reflects the health of body organs. A skin whitening agent, named seven whitening creams (also called Chi-Bai-San), has been used since ancient times in China. Chi-Bai-San reduces melanin and helps to reduce wrinkles. PURPOSE: We aimed to determine the skin-whitening ability and safe dose of the seven compounds in Chi-Bai-San. STUDY DESIGN: A common use for Chinese medicine is decocted in water. To mimic the function of Chi-Bai-San apply in clinical, we boiled all seven compound in water, respectively. These single recipe extractions and a mixture of these seven items were used in zebrafish embryo and B16F10 melanoma cell to identify the anti-melanogenesis function. METHODS: Chi-Bai-San comprises Bai-Lian (Ampelopsis japonica), Bai-Ji (Bletilla striata), Bai-Zhi (Angelica dahurica), Bai-Zhu (Atractylodes macrocephala), Bai-Shau (Paeonia lactiflora), Fu-Ling (Wolfiporia cocos), and Jen-Ju-Fen (Pearl powder). All components were extracted by heating in distilled water. The supernatant was collected after centrifugation. The extracted components were introduced into zebrafish embryos at different doses to determine the safe dose. B16F10 melanoma cells were treated with the final dose of each component and the component mixture. Melanin content and tyrosinase activity were assessed in zebrafish and B16F10 cells. Chi-Bai-San and its components were exposed to α MSH-induced B16F10 cells, and detected for mechanism of anti-melanogenesis pathway. RESULTS: Most compounds were not toxic at a low dose (0.1 mg/ml), except A. macrocephala, which resulted in a survival rate of only 30% at 72 hpf. The final dose of A. dahurica, P. lactiflora, W. cocos, and pearl was 1 mg/ml; that of A. japonica was 0.5 mg/ml; and that of A. macrocephala and B. striata was 0.1 mg/ml. Chi-Bai-San markedly decreased melanin content 37.47% in zebrafish embryos. Further, Chi-Bai-San abolished tyrosinase activity and MITF-mediated tyrosinase expression by down regulating the upstream transcription factors ZEB2, ß-catenin, and CREB2 in α MSH-induced B16F10 cells. Additionally, Chi-Bai-San might reduce melanosome secretion from melanocytes. CONCLUSION: Our findings indicate that safety and efficacy of heat-extracted Chi-Bai-San, which can reduce αMSH-induced melanin production by inhibiting the key role of melogenic-related transcription factor and promote the synergic effect of seven types of traditional Chinese herbal medicines.


Assuntos
Medicamentos de Ervas Chinesas , Melaninas/biossíntese , Melanoma Experimental , Monofenol Mono-Oxigenase/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Medicamentos de Ervas Chinesas/farmacologia , Melanoma Experimental/tratamento farmacológico , Peixe-Zebra
8.
Arterioscler Thromb Vasc Biol ; 41(1): e46-e62, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33176446

RESUMO

OBJECTIVE: Diabetic retinopathy, one of retinal vasculopathy, is characterized by retinal inflammation, vascular leakage, blood-retinal barrier breakdown, and neovascularization. However, the molecular mechanisms that contribute to diabetic retinopathy progression remain unclear. Approach and Results: Tpl2 (tumor progression locus 2) is a protein kinase implicated in inflammation and pathological vascular angiogenesis. Nε-carboxymethyllysine (CML) and inflammatory cytokines levels in human sera and in several diabetic murine models were detected by ELISA, whereas liquid chromatography-tandem mass spectrometry analysis was used for whole eye tissues. The CML and p-Tpl2 expressions on the human retinal pigment epithelium (RPE) cells were determined by immunofluorescence. Intravitreal injection of pharmacological inhibitor or NA (neutralizing antibody) was used in a diabetic rat model. Retinal leukostasis, optical coherence tomography, and H&E staining were used to observe pathological features. Sera of diabetic retinopathy patients had significantly increased CML levels that positively correlated with diabetic retinopathy severity and foveal thickness. CML and p-Tpl2 expressions also significantly increased in the RPE of both T1DM and T2DM diabetes animal models. Mechanistic studies on RPE revealed that CML-induced Tpl2 activation and NADPH oxidase, and inflammasome complex activation were all effectively attenuated by Tpl2 inhibition. Tpl2 inhibition by NA also effectively reduced inflammatory/angiogenic factors, retinal leukostasis in streptozotocin-induced diabetic rats, and RPE secretion of inflammatory cytokines. The attenuated release of angiogenic factors led to inhibited vascular abnormalities in the diabetic animal model. CONCLUSIONS: The inhibition of Tpl2 can block the inflammasome signaling pathway in RPE and has potential clinical and therapeutic implications in diabetes-associated retinal microvascular dysfunction.


Assuntos
Inibidores da Angiogênese/farmacologia , Retinopatia Diabética/prevenção & controle , Inflamassomos/antagonistas & inibidores , MAP Quinase Quinase Quinases/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Neovascularização Retiniana/prevenção & controle , Epitélio Pigmentado da Retina/efeitos dos fármacos , Idoso , Animais , Células Cultivadas , Estudos Transversais , Bases de Dados Factuais , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/diagnóstico , Diabetes Mellitus Experimental/enzimologia , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/enzimologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/enzimologia , Retinopatia Diabética/enzimologia , Retinopatia Diabética/etiologia , Retinopatia Diabética/patologia , Feminino , Humanos , Inflamassomos/metabolismo , MAP Quinase Quinase Quinases/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Gravidez , Estudos Prospectivos , Proteínas Proto-Oncogênicas/metabolismo , Neovascularização Retiniana/enzimologia , Neovascularização Retiniana/etiologia , Neovascularização Retiniana/patologia , Epitélio Pigmentado da Retina/enzimologia , Epitélio Pigmentado da Retina/patologia , Transdução de Sinais
9.
Cancer Lett ; 442: 113-125, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30391358

RESUMO

There is increasing global incidence of highly metastatic melanoma and therapeutic strategies like those focusing on the downstream beta-catenin/MITF axis of invading melanoma cells are urgently needed. Targeting endoplasmic reticulum (ER) stress can promote cancer cell death and inhibit epithelial mesenchymal transition (EMT) in metastatic tumors. This study aimed to determine if Honokiol could promote ER stress-dependent apoptosis and regulate metastatic melanoma. The therapeutic efficacy of Honokiol was assessed using the highly metastatic melanoma xenograft mouse model for peritoneal metastasis and evaluated by computed tomography imaging. The ER stress marker, Calpain-10, delineated a novel proteolytic cleavage enzyme, while CHOP/GADD153-regulated apoptosis was used for gene silencing to determine the role of the ß-catenin/MITF axis in melanoma cells. The results showed that Honokiol effectively decreased peritoneal dissemination and organ metastasis via ER stress activation and EMT marker inhibition. Knockdown Calpain-10 or CHOP/GADD153 blocked all of the biological effects in Honokiol-induced ß-catenin/MITF cleavage, ERSE or TCF/LEF luciferase activity, and ß-catenin kinase activity. These findings suggest that Honokiol can significantly thwart the progression of highly metastatic melanoma using the ß-catenin/MITF axis via prompt Calpain-10 and CHOP/GADD153 regulated cascades.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Compostos de Bifenilo/farmacologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Lignanas/farmacologia , Melanoma/tratamento farmacológico , Fator de Transcrição Associado à Microftalmia/metabolismo , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Fator de Transcrição CHOP/metabolismo , beta Catenina/metabolismo , Animais , Calpaína/genética , Calpaína/metabolismo , Linhagem Celular Tumoral , Quinase 2 Dependente de Ciclina/genética , Quinase 2 Dependente de Ciclina/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Melanoma/genética , Melanoma/metabolismo , Melanoma/secundário , Camundongos Endogâmicos BALB C , Camundongos Nus , Fator de Transcrição Associado à Microftalmia/genética , Neoplasias Peritoneais/genética , Neoplasias Peritoneais/metabolismo , Neoplasias Peritoneais/secundário , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Fator de Transcrição CHOP/genética , Via de Sinalização Wnt/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/genética
10.
Circ Res ; 121(6): e37-e52, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28724746

RESUMO

RATIONALE: Diabetic retinopathy is characterized by vasopermeability, vascular leakage, inflammation, blood-retinal barrier breakdown, capillary degeneration, and neovascularization. However, the mechanisms underlying the association between diabetes mellitus and progression retinopathy remain unclear. OBJECTIVE: TPL2 (tumor progression locus 2), a serine-threonine protein kinase, exerts a pathological effect on vascular angiogenesis. This study investigated the role of Nε-(carboxymethyl)lysine, a major advanced glycation end products, and the involved TPL2-related molecular signals in diabetic retinopathy using models of in vitro and in vivo and human samples. METHODS AND RESULTS: Serum Nε-(carboxymethyl)lysine levels and TPL2 kinase activity were significantly increased in clinical patients and experimental animals with diabetic retinopathy. Intravitreal administration of pharmacological blocker or neutralizing antibody inhibited TPL2 and effectively suppressed the pathological characteristics of retinopathy in streptozotocin-induced diabetic animal models. Intravitreal VEGF (vascular endothelial growth factor) neutralization also suppressed the diabetic retinopathy in diabetic animal models. Mechanistic studies in primary human umbilical vein endothelial cells and primary retinal microvascular endothelial cells from streptozotocin-diabetic rats, db/db mice, and samples from patients with diabetic retinopathy revealed a positive parallel correlation between Nε-(carboxymethyl)lysine and the TPL2/chemokine SDF1α (stromal cell-derived factor-α) axis that is dependent on endoplasmic reticulum stress-related molecules, especially ATF4 (activating transcription factor-4). CONCLUSIONS: This study demonstrates that inhibiting the Nε-(carboxymethyl)lysine-induced TPL2/ATF4/SDF1α axis can effectively prevent diabetes mellitus-mediated retinal microvascular dysfunction. This signaling axis may include the therapeutic potential for other diseases involving pathological neovascularization or macular edema.


Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Quimiocina CXCL12/metabolismo , Retinopatia Diabética/metabolismo , MAP Quinase Quinase Quinases/metabolismo , Animais , Células Cultivadas , Diabetes Mellitus Experimental/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Lisina/análogos & derivados , Lisina/sangue , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
11.
J Pineal Res ; 60(2): 142-54, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26514342

RESUMO

Peritoneal dissemination of tumor has high mortality and is associated with the loss of epithelial features, acquisition of motile mesenchymal morphology characteristics, and invasive properties by tumor cells. Melatonin is an endogenously produced molecule in all plant species that is known to exert antitumor activity, but to date, its underlying mechanisms and antiperitoneal metastasis efficacy is not well defined. This study determined the antiperitoneal dissemination potential of melatonin in vivo and assessed its association with the inhibition of epithelial-to-mesenchymal transition (EMT) signaling mechanism by endoplasmic reticulum (ER) stress, which may be a major molecular mechanism of melatonin against cancer. The results demonstrate that melatonin inhibited peritoneal metastasis in vivo and activated ER stress in Cignal ERSE Reporter Assay, organelle structure in transmission electron microscopy images, calpain activity, and protein biomarkers like p-elf2α. Moreover, the overexpression of transcription factor C/EBPß in gastric cancer interacted with NFκB and further regulates COX-2 expression. These were dissociated and downregulated by melatonin, as proven by immunofluorescence imaging, immunoprecipitation, EMSA, and ChIP assay. Melatonin or gene silencing of C/EBPß decreased the EMT protein markers (E-cadherin, Snail, and Slug) and Wnt/beta-catenin activity by Topflash activity, and increased ER stress markers. In an animal study, the results of melatonin therapy were consistent with those of in vitro findings and attenuated systemic proangiogenesis factor production. In conclusion, C/EBPß and NFκB inhibition by melatonin may impede both gastric tumor growth and peritoneal dissemination by inducing ER stress and inhibiting EMT.


Assuntos
Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Calpaína/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Melatonina/farmacologia , NF-kappa B/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Peritoneais/tratamento farmacológico , Proteólise/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Neoplasias Gástricas/tratamento farmacológico , Animais , Proteína beta Intensificadora de Ligação a CCAAT/genética , Calpaína/genética , Linhagem Celular Tumoral , Inativação Gênica , Humanos , Camundongos , NF-kappa B/genética , Proteínas de Neoplasias/genética , Neoplasias Peritoneais/genética , Neoplasias Peritoneais/metabolismo , Neoplasias Peritoneais/patologia , Neoplasias Peritoneais/secundário , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia
12.
Antioxid Redox Signal ; 24(4): 217-231, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26415004

RESUMO

AIMS: Activation of glomerular mesangial cells (MCs) and functional changes of renal tubular cells are due to metabolic abnormalities, oxidative stress, and matrix accumulation in the diabetic nephropathy (DN). Aryl hydrocarbon receptor (AhR) activation has been implicated in DN. In this study, we investigated the role of AhR in the pathophysiological processes of DN using AhR knockout (AhRKO) and pharmacological inhibitor α-naphthoflavone mouse models. RESULTS: The increased blood glucose, glucose intolerance, MC activation, macrophage infiltration, and extracellular matrix (ECM) accumulation were significantly attenuated in AhRKO mice with diabetic inducer streptozotocin (STZ) treatment. AhR deficiency by genetic knockout or pharmacological inhibition also decreased the induction of cyclooxygenase-2 (COX-2)/prostaglandin E2 (PGE2), lipid peroxidation, oxidative stress, NADPH oxidase activity, and N-ɛ-carboxymethyllysine (CML, a major advanced glycation end product) in STZ-induced diabetic mice. CML showed remarkably increased AhR/COX-2 DNA-binding activity, protein-DNA interactions, gene regulation, and ECM formation in MCs and renal proximal tubular cells, which could be reversed by siRNA-AhR transfection. CML-increased AhR nuclear translocation and biological activity in MCs and renal proximal tubular cells could also be effectively attenuated by antioxidants. INNOVATION: We elucidate for the first time that AhR plays an important role in MC activation, macrophage infiltration, and ECM accumulation in DN conferred by oxidative stress. CONCLUSIONS: AhR-regulated COX-2/PGE2 expression and ECM deposition through oxidative stress cascade is involved in the CML-triggered MC activation and macrophage infiltration. These findings suggest new insights into the development of therapeutic approaches to reduce diabetic microvascular complications. Antioxid. Redox Signal. 24, 217-231.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/deficiência , Nefropatias Diabéticas/metabolismo , Matriz Extracelular/patologia , Macrófagos/patologia , Células Mesangiais/patologia , Espécies Reativas de Oxigênio/metabolismo , Receptores de Hidrocarboneto Arílico/deficiência , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Benzoflavonas/farmacologia , Glicemia/metabolismo , Diabetes Mellitus Experimental/complicações , Nefropatias Diabéticas/genética , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Macrófagos/metabolismo , Células Mesangiais/efeitos dos fármacos , Células Mesangiais/metabolismo , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Receptores de Hidrocarboneto Arílico/genética , Estreptozocina
13.
Mol Oncol ; 9(4): 834-49, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25619450

RESUMO

Peritoneal dissemination is a major clinical obstacle in gastrointestinal cancer therapy, and it accounts for the majority of cancer-related mortality. Calreticulin (CRT) is over-expressed in gastric tumors and has been linked to poor prognosis. In this study, immunohistochemistry studies revealed that the up-regulation of CRT was associated with lymph node and distant metastasis in patients with gastric cancer specimens. CRT was significantly down-regulated in highly metastatic gastric cancer cell lines and metastatic animal by Honokiol-treated. Small RNA interference blocking CRT by siRNA-CRT was translocated to the cells in the early immunogenic response to Honokiol. Honokiol activated endoplasmic reticulum (ER) stress and down-regulated peroxisome proliferator-activated receptor-γ (PPARγ) activity resulting in PPARγ and CRT degradation through calpain-II activity, which could be reversed by siRNA-calpain-II. The Calpain-II/PPARγ/CRT axis and interaction evoked by Honokiol could be blocked by gene silencing or pharmacological agents. Both transforming growth factor (TGF)-ß1 and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) induced cell migration, invasion and reciprocal down-regulation of epithelial marker E-cadherin, which could be abrogated by siRNA-CRT. Moreover, Honokiol significantly suppressed MNNG-induced gastrointestinal tumor growth and over-expression of CRT in mice. Knockdown CRT in gastric cancer cells was found to effectively reduce growth ability and metastasis in vivo. The present study provides insight into the specific biological behavior of CRT in epithelial-to-mesenchymal transition (EMT) and metastasis. Taken together, our results suggest that the therapeutic inhibition of CRT by Honokiol suppresses both gastric tumor growth and peritoneal dissemination by dictating early translocation of CRT in immunogenic cell death, activating ER stress, and blocking EMT.


Assuntos
Compostos de Bifenilo/farmacologia , Calreticulina/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Lignanas/farmacologia , Neoplasias Gástricas/imunologia , Neoplasias Gástricas/patologia , Adulto , Animais , Biomarcadores Tumorais/metabolismo , Calpaína/metabolismo , Calreticulina/genética , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Feminino , Técnicas de Silenciamento de Genes , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Metilnitronitrosoguanidina , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Invasividade Neoplásica , PPAR gama/metabolismo , Fagocitose/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Ligação Proteica/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
14.
Oncotarget ; 5(17): 7788-804, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25226618

RESUMO

Biseugenol (Eug) is known to antiproliferative of cancer cells; however, to date, the antiperitoneal dissemination effects have not been studied in any mouse cancer model. In this study, Aryl hydrocarbon receptor (AhR) expression was associated with lymph node and distant metastasis in patients with gastric cancer and was correlated with clinicolpathological pattern. We evaluated the antiperitoneal dissemination potential of knockdown AhR and Biseugenol in cancer mouse model and assessed mesenchymal characteristics. Our results demonstrate that tumor growth, peritoneal dissemination and peritoneum or organ metastasis implanted MKN45 cells were significantly decreased in shAhR and Biseugenol-treated mice and that endoplasmic reticulum (ER) stress was caused. Biseugenol-exposure tumors showed acquired epithelial features such as phosphorylation of E-cadherin, cytokeratin-18 and loss mesenchymal signature Snail, but not vimentin regulation. Snail expression, through AhR activation, is an epithelial-to-mesenchymal transition (EMT) determinant. Moreover, Biseugenol enhanced Calpain-10 (Calp-10) and AhR interaction results in Snail downregulation. The effect of shCalpain-10 in cancer cells was associated with inactivation of AhR/Snail promoter binding activity. Inhibition of Calpain-10 in gastric cancer cells by short hairpin RNA or pharmacological inhibitor was found to effectively reduced growth ability and vessel density in vivo. Importantly, knockdown of AhR completed abrogated peritoneal dissemination. Herein, Biseugenol targeting ER stress provokes Calpain-10 activity, sequentially induces reversal of EMT and apoptosis via AhR may involve the paralleling processes. Taken together, these data suggest that Calpain-10 activation and AhR inhibition by Biseugenol impedes both gastric tumor growth and peritoneal dissemination by inducing ER stress and inhibiting EMT.


Assuntos
Adenocarcinoma/patologia , Antineoplásicos/farmacologia , Neoplasias Peritoneais/secundário , Receptores de Hidrocarboneto Arílico/biossíntese , Neoplasias Gástricas/patologia , Idoso , Animais , Imunoprecipitação da Cromatina , Modelos Animais de Doenças , Ensaio de Desvio de Mobilidade Eletroforética , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Imunofluorescência , Humanos , Immunoblotting , Imunoprecipitação , Masculino , Camundongos , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Receptores de Hidrocarboneto Arílico/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Carcinogenesis ; 34(11): 2568-79, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23828905

RESUMO

Honokiol is known to suppress the growth of cancer cells; however, to date, its antiperitoneal dissemination effects have not been studied in an orthotopic mouse model. In the present study, we evaluated the antiperitoneal dissemination potential of Honokiol in an orthotopic mouse model and assessed associations with tumor growth factor-ß1 (TGFß1) and cells stimulated by a carcinogen, N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Our results demonstrate that tumor growth, peritoneal dissemination and peritoneum or organ metastasis of orthotopically implanted MKN45 cells were significantly decreased in Honokiol-treated mice and that endoplasmic reticulum (ER) stress was induced. Honokiol-treated tumors showed increased epithelial signatures such as E-cadherin, cytokeratin-18 and ER stress marker. In contrast, decreased expression of vimentin, Snail and tumor progression locus 2 (Tpl2) was also noted. TGFß1 and MNNG-induced downregulation of E-cadherin and upregulation of Tpl2 were abrogated by Honokiol treatment. The effect of Tpl2 inhibition in cancer cells or endothelial cells was associated with inactivation of CCAAT/enhancer binding protein B, nuclear factor kappa-light-chain-enhancer of activated B cell and activator protein-1 and suppression of vascular endothelial growth factor. Inhibition of Tpl2 in gastric cancer cells by small interfering RNA or pharmacological inhibitor was found to effectively reduce growth ability and vessel density in vivo. Honokiol-induced reversal of epithelial-to-mesenchymal transition (EMT) and ER stress-induced apoptosis via Tp12 may involve the paralleling processes. Taken together, our results suggest that the therapeutic inhibition of Tpl2 by Honokiol thwarts both gastric tumor growth and peritoneal dissemination by inducing ER stress and inhibiting EMT.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Compostos de Bifenilo/farmacologia , Lignanas/farmacologia , MAP Quinase Quinase Quinases/metabolismo , Neoplasias Peritoneais/prevenção & controle , Fitoterapia , Proteínas Proto-Oncogênicas/metabolismo , Neoplasias Gástricas/prevenção & controle , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Imunofluorescência , Humanos , Técnicas Imunoenzimáticas , Imunoprecipitação , Luciferases/metabolismo , MAP Quinase Quinase Quinases/antagonistas & inibidores , MAP Quinase Quinase Quinases/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Peritoneais/metabolismo , Neoplasias Peritoneais/secundário , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Células Tumorais Cultivadas
16.
IEEE Trans Nanobioscience ; 10(2): 69-75, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21742572

RESUMO

The protein folding problem is a fundamental problem in computational molecular biology and biochemical physics. The previously best known branch and bound method for the protein folding problem may find optimal or near-optimal energy structure from the benchmark sequences, but the total computation time is rather lengthy because it usually needs to run a great deal of simulating tests or else lack of accuracy. In this paper, we develop a new branch and bound method for the the protein folding problem under the two-dimensional HP model to overcome the mentioned drawbacks. By using benchmark sequences for evaluation, we demonstrate that the performance of our method is superior than previously known methods. Moreover, our method is a simple, flexible and easily implemented one for the protein folding problem.


Assuntos
Algoritmos , Biologia Computacional/métodos , Modelos Químicos , Dobramento de Proteína , Proteínas/química , Sequência de Aminoácidos , Aminoácidos , Interações Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Proteínas/metabolismo
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