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1.
Res Sq ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38947036

RESUMO

The Cystine-xCT transporter-Glutathione (GSH)-GPX4 axis is the canonical pathway to protect against ferroptosis. While not required for ferroptosis-inducing compounds (FINs) targeting GPX4, FINs targeting the xCT transporter require mitochondria and its lipid peroxidation to trigger ferroptosis. However, the mechanism underlying the difference between these FINs is still unknown. Given that cysteine is also required for coenzyme A (CoA) biosynthesis, here we show that CoA supplementation specifically prevents ferroptosis induced by xCT inhibitors but not GPX4 inhibitors. We find that, auranofin, a thioredoxin reductase inhibitor, abolishes the protective effect of CoA. We also find that CoA availability determines the enzymatic activity of thioredoxin reductase, but not thioredoxin. Importantly, the mitochondrial thioredoxin system, but not the cytosolic thioredoxin system, determines CoA-mediated ferroptosis inhibition. Our data show that the CoA regulates the in vitro enzymatic activity of mitochondrial thioredoxin reductase (TXNRD2) by covalently modifying the thiol group of cysteine (CoAlation) on Cys-483. Replacing Cys-483 with alanine on TXNRD2 abolishes its in vitro enzymatic activity and ability to protect cells from ferroptosis. Targeting xCT to limit cysteine import and, therefore, CoA biosynthesis reduced CoAlation on TXNRD2, an effect that was rescued by CoA supplementation. Furthermore, the fibroblasts from patients with disrupted CoA metabolism demonstrate increased mitochondrial lipid peroxidation. In organotypic brain slice cultures, inhibition of CoA biosynthesis leads to an oxidized thioredoxin system, mitochondrial lipid peroxidation, and loss in cell viability, which were all rescued by ferrostatin-1. These findings identify CoA-mediated post-translation modification to regulate the thioredoxin system as an alternative ferroptosis protection pathway with potential clinical relevance for patients with disrupted CoA metabolism.

2.
J Immunother Cancer ; 12(2)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38336371

RESUMO

BACKGROUND: Immune checkpoint inhibitor (ICI) combinations represent an emerging treatment strategies in cancer. However, their efficacy in microsatellite stable (MSS) or mismatch repair-proficient (pMMR) colorectal cancer (CRC) is variable. Here, a multiomic characterization was performed to identify predictive biomarkers associated with patient response to ICI combinations in MSS/pMMR CRC for the further development of ICI combinations. METHODS: Whole-exome sequencing, RNA sequencing, and multiplex fluorescence immunohistochemistry of tumors from patients with MSS/pMMR CRC, who received regorafenib plus nivolumab (REGONIVO) or TAS-116 plus nivolumab (TASNIVO) in clinical trials were conducted. Twenty-two and 23 patients without prior ICI from the REGONIVO and TASNIVO trials were included in this study. A biomarker analysis was performed using samples from each of these studies. RESULTS: The epithelial-mesenchymal transition pathway and genes related to cancer-associated fibroblasts were upregulated in the REGONIVO responder group, and the G2M checkpoint pathway was upregulated in the TASNIVO responder group. The MYC pathway was upregulated in the REGONIVO non-responder group. Consensus molecular subtype 4 was significantly associated with response (p=0.035) and longer progression-free survival (p=0.006) in the REGONIVO trial. CD8+ T cells, regulatory T cells, and M2 macrophages density was significantly higher in the REGONIVO trial responders than in non-responders. Mutations in the POLE gene and patient response were significantly associated in the TASNIVO trial; however, the frequencies of other mutations or tumor mutational burden were not significantly different between responders and non-responders in either trial. CONCLUSIONS: We identified molecular features associated with the response to the REGONIVO and TASNIVO, particularly those related to tumor microenvironmental factors. These findings are likely to contribute to the development of biomarkers to predict treatment efficacy for MSS/pMMR CRC and future immunotherapy combinations for treatment.


Assuntos
Neoplasias Colorretais , Nivolumabe , Humanos , Nivolumabe/farmacologia , Nivolumabe/uso terapêutico , Linfócitos T CD8-Positivos , Multiômica , Imunoterapia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Biomarcadores
3.
Antiviral Res ; 219: 105735, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37858764

RESUMO

A class of 1-(4-(arylethylenylcarbonyl)phenyl)-4-carboxy-2-pyrrolidinones were designed and synthesized via Michael addition, cyclization, aldol condensation, and deprotonation to inhibit the human transmembrane protease serine 2 (TMPRSS2) and Furin, which are involved in priming the SARS-CoV-2 Spike for virus entry. The most potent inhibitor 2f (81) was found to efficiently inhibit the replication of various SARS-CoV-2 delta and omicron variants in VeroE6 and Calu-3 cells, with EC50 range of 0.001-0.026 µM by pre-incubation with the virus to avoid the virus entry. The more potent antiviral activities than the proteases inhibitory activities led to discovery that the synthesized compounds also inhibited Spike's receptor binding domain (RBD):angiotensin converting enzyme 2 (ACE2) interaction as a main target, and their antiviral activities were enhanced by inhibiting TMPRSS2 and/or Furin. To further confirm the blocking effect of 2f (81) on virus entry, SARS-CoV-2 Spike pseudovirus was used in the entry assay and the results showed that the compound inhibited the pseudovirus entry in a ACE2-dependent pathway, via mainly inhibiting RBD:ACE2 interaction and TMPRSS2 activity in Calu-3 cells. Finally, in the in vivo animal model of SARS-CoV-2 infection, the oral administration of 25 mg/kg 2f (81) in hamsters resulted in reduced bodyweight loss and 5-fold lower viral RNA levels in nasal turbinate three days post-infection. Our findings demonstrated the potential of the lead compound for further preclinical investigation as a potential treatment for SARS-CoV-2.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Humanos , Furina/farmacologia , Enzima de Conversão de Angiotensina 2/química , Pirrolidinonas/farmacologia , Antivirais/farmacologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus
4.
J Heart Lung Transplant ; 42(5): 575-584, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36707296

RESUMO

BACKGROUND: In lung transplantation, ischemia-reperfusion injury associated with mitochondrial damage can lead to graft rejection. Intact, exogenous mitochondria provide a unique treatment option to salvage damaged cells within lung tissue. METHODS: We developed a novel method to freeze and store allogeneic mitochondria isolated from porcine heart tissue. Stored mitochondria were injected into a model of induced ischemia-reperfusion injury using porcine ex-vivo lung perfusion. Treatment benefits to immune modulation, antioxidant defense, and cellular salvage were evaluated. These findings were corroborated in human lungs undergoing ex-vivo lung perfusion. Lung tissue homogenate and primary lung endothelial cells were then used to address underlying mechanisms. RESULTS: Following cold ischemia, mitochondrial transplant reduced lung pulmonary vascular resistance and tissue pro-inflammatory signaling and cytokine secretion. Further, exogenous mitochondria reduced reactive oxygen species by-products and promoted glutathione synthesis, thereby salvaging cell viability. These results were confirmed in a human model of ex-vivo lung perfusion wherein transplanted mitochondria decreased tissue oxidative and inflammatory signaling, improving lung function. We demonstrate that transplanted mitochondria induce autophagy and suggest that bolstered autophagy may act upstream of the anti-inflammatory and antioxidant benefits. Importantly, chemical inhibitors of the MEK autophagy pathway blunted the favorable effects of mitochondrial transplant. CONCLUSIONS: These data provide direct evidence that mitochondrial transplant improves cellular health and lung function when administered during ex-vivo lung perfusion and suggest the mechanism of action may be through promotion of cellular autophagy. Data herein contribute new insights into the therapeutic potential of mitochondrial transplant to abate ischemia-reperfusion injury during lung transplant, and thus reduce graft rejection.


Assuntos
Transplante de Pulmão , Traumatismo por Reperfusão , Humanos , Suínos , Animais , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Células Endoteliais/metabolismo , Pulmão , Reperfusão , Mitocôndrias/metabolismo , Transplante de Pulmão/métodos , Isquemia , Traumatismo por Reperfusão/metabolismo , Perfusão/métodos
5.
Sci Immunol ; 7(76): eabk0957, 2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-36206353

RESUMO

Regulatory T (Treg) cells suppress effective antitumor immunity in tumor-bearing hosts, thereby becoming promising targets in cancer immunotherapy. Despite the importance of Treg cells in tumor immunity, little is known about their differentiation process and epigenetic profiles in the tumor microenvironment (TME). Here, we showed that Treg cells in the TME of human lung cancers harbored a completely different open chromatin profile compared with CD8+ T cells, conventional CD4+ T cells in the TME, and peripheral Treg cells. The integrative sequencing analyses including ATAC, single-cell RNA, and single-cell ATAC sequencing revealed that BATF, IRF4, NF-κB, and NR4A were important transcription factors for Treg cell differentiation in the TME. In particular, BATF was identified as a key regulator, which leveraged Treg cell differentiation through epigenetically controlling activation-associated gene expression, resulting in the robustness of Treg cells in the TME. The single-cell sequencing approaches also revealed that tissue-resident and tumor-infiltrating Treg cells followed a common pathway for differentiation and activation in a BATF-dependent manner heading toward Treg cells with the most differentiated and activated phenotypes in tissues and tumors. BATF deficiency in Treg cells remarkably inhibited tumor growth, and high BATF expression was associated with poor prognosis in lung cancer, kidney cancer, and melanoma. These findings indicate one of the specific chromatin remodeling and differentiation programs of Treg cells in the TME, which can be applied in the development of Treg cell-targeted therapies.


Assuntos
Melanoma , Linfócitos T Reguladores , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Linfócitos T CD8-Positivos , Cromatina/metabolismo , Humanos , NF-kappa B/genética , NF-kappa B/metabolismo , RNA , Microambiente Tumoral
6.
Clin Cancer Res ; 28(16): 3480-3488, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35679062

RESUMO

PURPOSE: We previously reported preliminary activity of regorafenib plus nivolumab (REGONIVO) or lenvatinib plus pembrolizumab (LENPEM) in advanced gastric cancer (AGC). Meanwhile, several studies demonstrated liver metastases are less responsive to immunotherapy. PATIENTS AND METHODS: Combined efficacy outcomes with a longer follow-up in a phase Ib trial of REGONIVO and a phase II trial of LENPEM were examined in AGC with or without liver metastases (REGONIVO plus LENPEM cohort). We also investigated the efficacy of anti-PD-1 monotherapies (anti-PD-1 monotherapy cohort). A comparison of the immune microenvironment between gastric primary tumors and liver metastases was also conducted by multiplex IHC. RESULTS: In the REGONIVO plus LENPEM cohort, with a median follow-up of 14.0 months, objective response rate (ORR), median progression-free survival (mPFS), and median overall survival (mOS) were 46%, 7.8 months, and 15.6 months in patients with liver metastases, while 69%, 6.9 months, and 15.5 months in those without. In the anti-PD-1 monotherapy cohort, with a median follow-up of 27.6 months, ORR, mPFS, and mOS were 9%, 1.4 months, and 6.4 months in patients with liver metastases, while 22%, 2.3 months, and 9.0 months in those without. Multiplex IHC revealed liver metastases were associated with an abundance of immune-suppressive cells, such as tumor-associated macrophages and regulatory T cells, with fewer CD8+ T cells compared with gastric primary tumors. CONCLUSIONS: Anti-PD-1 antibodies plus regorafenib or lenvatinib for AGC showed promising antitumor activity with a longer follow-up, irrespective of liver metastases status, despite a more immune-suppressive tumor microenvironment in liver metastases.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Hepáticas , Neoplasias Gástricas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ensaios Clínicos como Assunto , Humanos , Imunoterapia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Nivolumabe/uso terapêutico , Intervalo Livre de Progressão , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia , Resultado do Tratamento , Microambiente Tumoral
7.
Cancer Cell ; 40(2): 201-218.e9, 2022 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-35090594

RESUMO

The balance of programmed death-1 (PD-1)-expressing CD8+ T cells and regulatory T (Treg) cells in the tumor microenvironment (TME) determines the clinical efficacy of PD-1 blockade therapy through the competition of their reactivation. However, factors that determine this balance remain unknown. Here, we show that Treg cells gain higher PD-1 expression than effector T cells in highly glycolytic tumors, including MYC-amplified tumors and liver tumors. Under low-glucose environments via glucose consumption by tumor cells, Treg cells actively absorbed lactic acid (LA) through monocarboxylate transporter 1 (MCT1), promoting NFAT1 translocation into the nucleus, thereby enhancing the expression of PD-1, whereas PD-1 expression by effector T cells was dampened. PD-1 blockade invigorated the PD-1-expressing Treg cells, resulting in treatment failure. We propose that LA in the highly glycolytic TME is an active checkpoint for the function of Treg cells in the TME via upregulation of PD-1 expression.


Assuntos
Regulação Neoplásica da Expressão Gênica , Ácido Láctico/metabolismo , Receptor de Morte Celular Programada 1/genética , Linfócitos T Reguladores/metabolismo , Microambiente Tumoral/genética , Animais , Biomarcadores Tumorais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Imunofluorescência , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glicólise , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Proteínas de Checkpoint Imunológico/metabolismo , Imunofenotipagem , Ácido Láctico/farmacologia , Ativação Linfocitária , Contagem de Linfócitos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Linfócitos do Interstício Tumoral/patologia , Camundongos , Terapia de Alvo Molecular , Prognóstico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/metabolismo , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Resultado do Tratamento , Microambiente Tumoral/efeitos dos fármacos
8.
Front Pharmacol ; 12: 670254, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34349644

RESUMO

Bone remodeling, a dynamic process in which bone formation by osteoblast is preceded by bone resorption by osteoclast, is a vital physiological process for maintaining bone mass and strength, imbalances in which could precipitate osteoporosis. Due to the unilateral mechanism of the existing bone remodeling drugs, identifying compounds that could regulate the balance between osteoclast and osteoblast could improve the treatment of osteoporosis. Here, we show that compounds isolated from Wikstroemia taiwanensis modulate osteoclast and osteoblast activities. Specifically, astragalin (1) and kaempferol 3-O-ß-D-apiofuranosyl-(1→6)-ß-D-glucopyranoside (2), besides increasing mineral deposition, increased alkaline phosphatase activity (137.2% for 1 and 115.8% for 2) and ESR-α expression (112.8% for 1 and 122.5% for 2) in primary human osteoblasts. In contrast, compounds 1, 2, 3, and 5 inhibited tartrate-resistant acid phosphatase (TRAP) activity in receptor activator of nuclear factor-κB ligand-induced osteoclasts by 40.8, 17.1, 25.9, and 14.5% and also decreased the number of TRAP-positive cells by 51.6, 26.8, 20.5, and 18.6%, respectively. Our findings, therefore, showed that compounds isolated from W. taiwanensis could increase osteoblast activity while simultaneously decreasing osteoclast activity, and hence, warrant further evaluation for development as anti-osteoporosis agents.

9.
Oncogene ; 40(11): 2018-2034, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33603168

RESUMO

Recurrent breast cancer presents significant challenges with aggressive phenotypes and treatment resistance. Therefore, novel therapeutics are urgently needed. Here, we report that murine recurrent breast tumor cells, when compared with primary tumor cells, are highly sensitive to ferroptosis. Discoidin Domain Receptor Tyrosine Kinase 2 (DDR2), the receptor for collagen I, is highly expressed in ferroptosis-sensitive recurrent tumor cells and human mesenchymal breast cancer cells. EMT regulators, TWIST and SNAIL, significantly induce DDR2 expression and sensitize ferroptosis in a DDR2-dependent manner. Erastin treatment induces DDR2 upregulation and phosphorylation, independent of collagen I. Furthermore, DDR2 knockdown in recurrent tumor cells reduces clonogenic proliferation. Importantly, both the ferroptosis protection and reduced clonogenic growth may be compatible with the compromised YAP/TAZ upon DDR2 inhibition. Collectively, these findings identify the important role of EMT-driven DDR2 upregulation in recurrent tumors in maintaining growth advantage but activating YAP/TAZ-mediated ferroptosis susceptibility, providing potential strategies to eradicate recurrent breast cancer cells with mesenchymal features.


Assuntos
Neoplasias da Mama/genética , Receptor com Domínio Discoidina 2/genética , Ferroptose/genética , Recidiva Local de Neoplasia/genética , Animais , Neoplasias da Mama/patologia , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Regulação Neoplásica da Expressão Gênica/genética , Via de Sinalização Hippo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Camundongos , Recidiva Local de Neoplasia/patologia , Proteínas Nucleares/genética , Fosforilação , Piperazinas/farmacologia , Proteínas Serina-Treonina Quinases/genética , Transdução de Sinais/genética , Fatores de Transcrição da Família Snail/genética , Fatores de Transcrição/genética , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional , Proteína 1 Relacionada a Twist/genética
10.
Biol Open ; 10(2)2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33372065

RESUMO

The development of three-dimensional cell culture techniques has allowed cancer researchers to study the stemness properties of cancer cells in in vitro culture. However, a method to grow PAX3-FOXO1 fusion-positive rhabdomyosarcoma (FP-RMS), an aggressive soft tissue sarcoma of childhood, has to date not been reported, hampering efforts to identify the dysregulated signaling pathways that underlie FP-RMS stemness. Here, we first examine the expression of canonical stem cell markers in human RMS tumors and cell lines. We then describe a method to grow FP-RMS cell lines as rhabdospheres and demonstrate that these spheres are enriched in expression of canonical stemness factors as well as Notch signaling components. Specifically, FP-RMS rhabdospheres have increased expression of SOX2, POU5F1 (OCT4), and NANOG, and several receptors and transcriptional regulators in the Notch signaling pathway. FP-RMS rhabdospheres also exhibit functional stemness characteristics including multipotency, increased tumorigenicity in vivo, and chemoresistance. This method provides a novel practical tool to support research into FP-RMS stemness and chemoresistance signaling mechanisms.


Assuntos
Células-Tronco Neoplásicas/metabolismo , Receptores Notch/metabolismo , Rabdomiossarcoma Alveolar/metabolismo , Rabdomiossarcoma Alveolar/patologia , Transdução de Sinais , Biomarcadores , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Células-Tronco Neoplásicas/patologia
12.
J Ethnopharmacol ; 264: 113126, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32763416

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Postmenopausal osteoporosis is a major bone health issue worldwide. There is an unmet medical need for osteoporosis treatments, a disease which disproportionately impacts women. Exploring botanicals to prevent or treat osteoporosis is currently an interest of investigations. Rhizomes of Davallia mariesii T. Moore ex Baker (Davalliacea) are used an indigenous herbal medicine in Asia for injuries due to fractures, contusions, and strains. AIM OF THE STUDY: In the present study, we investigated the osteogenic effect of the water extract of rhizomes of D. mariesii (DMH) on bone loss induced by an ovariectomy (OVX) in mice and also its impact on osteogenesis in primary human osteoblasts (HObs). Additionally, we performed a quantitative analysis of compounds in the DMH extract. MATERIALS AND METHODS: OVX C57BL/6J mice were orally administrated DMH extract for 12 weeks, and microarchitecture parameters were examined by microcomputed tomography. DMH extract was fractionated in a bio-guided manner, and fractions were isolated to obtain active compounds using HObs. Cell viability was evaluated by an MTT assay. Characteristics of early and late osteogenesis were analyzed by alkaline phosphatase activity and a mineralization assay. Molecular mechanisms were explored by a real-time quantitative PCR. Compounds in the DMH extract were identified and quantified using liquid chromatography tandem mass spectroscopy (LC-MS/MS). RESULTS: DMH improved bone mineral densities of vertebrae and the femur. Through microarchitectural observations, DMH significantly decreased the bone surface/volume ratio and trabecular separation, and also increased the connectivity density in the OVX group. Additionally, DMH inhibited osteoclast differentiation in receptor activator of nuclear factor-κB ligand-induced osteoclasts and increased bone formation in HObs. After bio-guided fractionation and isolation, we found that eriodictyol-7-O-ß-d-glucuronide (2) significantly increased alkaline phosphatase activity, and 5-O-ß-d-(6-O-vanilloylglucopyranosyl)gentisic acid (3) substantially enhanced mineral deposition. In HObs, compound 3 was more potent in upregulating expressions of bone morphogenetic protein-2, bone sialoprotein, osteopontin, osterix, and estrogen receptor-α. The amount of bioactive compound 3 in DMH was 5.68 ±â€¯0.64 mg/g of dry weight according to LC-MS/MS. CONCLUSION: For the first time we report that D. mariesii and its isolated compounds demonstrated potent osteogenic activities. Quantitative results of D. mariesii could be a reference for phytochemical analyses.


Assuntos
Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Plantas Medicinais , Animais , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos/métodos , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Osteoblastos/metabolismo , Osteogênese/fisiologia , Osteoporose/diagnóstico por imagem , Osteoporose/metabolismo , Ovariectomia/efeitos adversos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Células RAW 264.7 , Microtomografia por Raio-X/métodos
13.
Saudi J Biol Sci ; 27(9): 2227-2237, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32884403

RESUMO

The process of bone metabolism includes catabolism of old or mature bone and anabolism of new bone, carried out by osteoclasts and osteoblasts respectively. Any imbalance in this process results in loss of bone mass or osteoporosis. Drugs available to combat osteoporosis have certain adverse effects and are unable to improve bone formation, hence identifying new agents to fulfil these therapeutic gaps is required. To expand the scope of potential agents that enhance bone formation, we identified Euonymus spraguei Hayata as a plant material that possesses robust osteogenic potential using human osteoblast cells. We isolated three compounds, syringaresinol (1), syringin (2), and (-)-epicatechin (3), from E. spraguei. Results demonstrated that syringin (2), and (-)-epicatechin (3), increased alkaline phosphatase activity significantly up to 131.01% and 130.67%, respectively; they also elevated mineral deposition with respective values of up to 139.39% and 138.33%. In addition, 2 and 3 modulated autophagy and the bone morphogenetic protein (BMP)-2 signaling pathway. Our findings demonstrated that 2 and 3 induced osteogenesis by targeting multiple pathways and therefore can be considered as potent multi-targeted drugs for bone formation against osteoporosis.

14.
Food Funct ; 11(6): 5420-5431, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32475999

RESUMO

Osteogenesis plays a vital role in the maintenance of bone health. Imbalances in osteogenesis influence the onset of several bone loss-associated diseases. The intake of Uraria crinita (Fabaceae) through dietary supplements is advised for childhood bone dysplasia. This botanical provides edible tonics and detoxifiers, and is also used as a folk beverage. We evaluated the osteogenic effects of a 50% ethanol extract of the root of U. crinita on primary human osteoblasts (HObs) and initiated a novel comprehensive phytochemical strategy using liquid chromatography-tandem mass spectrometry (LC-MS/MS) for quality control of this functional food. Two isoflavones, genistein (5) and 5,7-dihydroxy-3',5'-dihydroxyisoflavone (6), increased the alkaline phosphatase activity (differentiation stage); the flavone glycoside vitexin (1), and the phenolic acid salicylic acid (2) enhanced the mineralization (mature stage). The isoflavone 2'-hydroxygenistein (4) possessed high osteogenic potential among the isolated compounds in HObs. It promoted osteogenesis-related stages and upregulated the gene expressions in a dose-dependent manner. The major compounds in the active fraction were quantitatively analyzed via phytochemical fingerprint detection. These LC-MS/MS-based phytochemical perspectives can act as reference standards in developing food supplements from U. crinita.


Assuntos
Cromatografia Líquida/métodos , Fabaceae/química , Osteogênese/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Espectrometria de Massas em Tandem/métodos , Doenças do Desenvolvimento Ósseo/tratamento farmacológico , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Criança , Feminino , Expressão Gênica , Genisteína/farmacologia , Glicosídeos/farmacologia , Humanos , Isoflavonas/farmacologia , Pessoa de Meia-Idade , Osteoblastos/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Raízes de Plantas/química , População Branca
15.
Cell Death Differ ; 27(7): 2234-2247, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31988496

RESUMO

The molecular and genetic basis of tumor recurrence is complex and poorly understood. RIPK3 is a key effector in programmed necrotic cell death and, therefore, its expression is frequently suppressed in primary tumors. In a transcriptome profiling between primary and recurrent breast tumor cells from a murine model of breast cancer recurrence, we found that RIPK3, while absent in primary tumor cells, is dramatically reexpressed in recurrent breast tumor cells by an epigenetic mechanism. Unexpectedly, we found that RIPK3 knockdown in recurrent tumor cells reduced clonogenic growth, causing cytokinesis failure, p53 stabilization, and repressed the activities of YAP/TAZ. These data uncover a surprising role of the pro-necroptotic RIPK3 kinase in enabling productive cell cycle during tumor recurrence. Remarkably, high RIPK3 expression also rendered recurrent tumor cells exquisitely dependent on extracellular cystine and undergo necroptosis upon cystine deprivation. The induction of RIPK3 in recurrent tumors unravels an unexpected mechanism that paradoxically confers on tumors both growth advantage and necrotic vulnerability, providing potential strategies to eradicate recurrent tumors.


Assuntos
Cistina/metabolismo , Neoplasias Mamárias Animais/patologia , Recidiva Local de Neoplasia/patologia , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Regulação para Cima/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Mamárias Animais/genética , Mitose/efeitos dos fármacos , Recidiva Local de Neoplasia/genética , Piperazinas/farmacologia , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transcriptoma/genética , Ensaio Tumoral de Célula-Tronco , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima/efeitos dos fármacos , Proteínas de Sinalização YAP
16.
Cell Biol Int ; 44(2): 381-390, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31508857

RESUMO

RASSF4, a member of the classical RASSF family of scaffold proteins, is associated with alveolar rhabdomyosarcoma, an aggressive pediatric cancer of muscle histogenesis. However, the role of RASSF4 in normal myogenesis is unknown. We demonstrate here that RASSF4 is necessary for early in vitro myogenesis. Using primary human myoblasts, we show that RASSF4 expression is dramatically increased during in vitro myogenic differentiation, and conversely that RASSF4-deficient myoblasts cannot differentiate, potentially because of a lack of upregulation of myogenin. In microscopy studies, we show that RASSF4 protein co-localizes with proteins of the myogenic microtubule-organizing center (MTOC) both before and after myogenic differentiation. RASSF4-deficient cells subject to differentiation conditions demonstrate a lack of shape change, suggesting that RASSF4 plays a role in promoting microtubule reorganization and myoblast elongation. In biochemical studies of myotubes, RASSF4 associates with MST1, suggesting that RASSF4 signals to MST1 in the myogenic differentiation process. Expression of MST1 in myoblasts partially reversed the effect of RASSF4 knockdown on differentiation, suggesting that RASSF4 and MST1 coordinately support myogenic differentiation. These data show that RASSF4 is critical for the early steps of myogenic differentiation.


Assuntos
Diferenciação Celular , Desenvolvimento Muscular , Músculo Esquelético/citologia , Mioblastos/citologia , Proteínas Supressoras de Tumor/metabolismo , Células Cultivadas , Humanos , Músculo Esquelético/metabolismo , Mioblastos/metabolismo , Transdução de Sinais
17.
J Food Drug Anal ; 28(1): 147-158, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31883603

RESUMO

The incidence of neurodegeneration leading to the conditions such as Alzheimer's and Parkinson's diseases are on the increase, they require the approaches that focus on protection prevention rather than treatment. Plants are rich sources of many compounds which possess medicinal properties. We sought to investigate the neuroprotective effects of Uncariahirsuta and its compounds on d-galactose-induced stress in BALB/c mice as well as 6-hydroxydopamine (6-OHDA)-induced stress in mouse nerve growth factor (mNGF)-differentiated PC12 cells. Our results demonstrate that the 95% ethanol extract of U. hirsuta reversed the d-galactose-induced learning and memory dysfunctions and decreased the malodialdehyde levels. Furthermore, the isolated compounds, 5ß-carboxystrictosidine (1) and chlorogenic acid (2), protected mNGF-differentiated PC12 cells against toxicity induced by 6-OHDA by acting as antiapoptotic agents. The 50% inhibitory concentration (IC50) for intracellular reactive oxygen species (ROS) scavenging was found to be 24.5 (for 1) and 19.7 µM (for 2), and both 1 and 2 reduced intracellular calcium levels with respective IC50 values of 46.9 and 27 µM. Interestingly, both compounds inhibited caspase 3 and 9 activities with respective IC50 values of 25.6 and 24.5 µM for 1 and 19.4 and 16.3 µM for 2. Our results identify U. hirsuta and its active compounds as potential neuroprotective agents and deserve further evaluation for drug development for neuroprotection in the future.


Assuntos
Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/farmacologia , Uncaria/química , Animais , Sobrevivência Celular , Aprendizagem/efeitos dos fármacos , Memória/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Estresse Oxidativo , Oxidopamina/toxicidade , Células PC12 , Ratos , Espécies Reativas de Oxigênio/metabolismo
18.
Polymers (Basel) ; 11(6)2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151173

RESUMO

The electronic package interconnects electronic signals from one area to another and package delamination is a serious problem in the configuration of materials. This study focused on decreasing the delamination of the low-profile fine pitch ball grid array (LFBGA) and plastic ball grid array (PBGA) packages in terms of polymer thermal issue, metal bonding and bonding mechanisms. PBGA and LFBGA are a very common type of packaging processes in the electronics industry. The present study dealt first with delamination of the LFBGA packaging, through characterization and determination of physical and chemical properties such as surface roughness, surface energy, and contact angle. The relationship between surface roughness and delamination was verified through various roughness bonding experiments. In addition, the surface energy was determined by measuring the contact angle after cleaning the metal surface of Cu, Ni and Cr with Ar + O2 gas, and, this gas plasma treatment was applied to enhance the adhesive properties. The compositions of the surface were analyzed through an X-ray photoelectron spectroscopy (XPS). Also, the delamination issue between the corner of the heat sink cap and the epoxy resin was observed for delamination of the LFBGA packaging. Further, this study analyzed the PBGA packaging process through the finite element analysis simulation software ANSYS. To improve the heat sink cap delamination issue of the PBGA, a new chamfer design of the corner seat was streamlined to decrease the stress value and delamination. Besides, the simulation results demonstrated that the stress value reduced after increasing the shoulder length. The results implicate that the stress value is inversely proportional to the shoulder width and the chamfer radius. This study demonstrated that the optimization in design was able reduce the delamination phenomena in configuration material.

19.
Int J Mol Sci ; 20(13)2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31247918

RESUMO

Bone metabolism is a homeostatic process, imbalance in which leads to the onset of diseases such as osteoporosis and osteopenia. Although several drugs are currently available to treat such conditions, they are associated with severe side effects and do not enhance bone formation. Thus, identifying alternative treatment strategies that focus on enhancing bone formation is essential. Herein, we explored the osteogenic potential of Turpinia formosana Nakai using human osteoblast (HOb) cells. The plant extract was subjected to various chromatographic techniques to obtain six compounds, including one new compound: 3,3'-di-O-methylellagic acid-4-O-α-l-arabinofuranoside (1). Compounds 3,3'-di-O-methylellagic acid-4-O-α-l-arabinofuranoside (1), gentisic acid 5-O-ß-d-(6'-O-galloyl) glucopyranoside (2), strictinin (3), and (-)-epicatechin-3-O-ß-d-allopyranoside (6) displayed no significant cytotoxicity toward HOb cells, and thus their effects on various osteogenic markers were analyzed. Results showed that 1-3 and 6 significantly increased alkaline phosphatase (ALP) activity up to 120.0, 121.3, 116.4, and 125.1%, respectively. Furthermore, 1, 2, and 6 also markedly enhanced the mineralization process with respective values of up to 136.4, 118.9, and 134.6%. In addition, the new compound, 1, significantly increased expression levels of estrogen receptor-α (133.4%) and osteogenesis-related genes of Runt-related transcription factor 2 (Runx2), osteopontin (OPN), bone morphogenetic protein (BMP)-2, bone sialoprotein (BSP), type I collagen (Col-1), and brain-derived neurotropic factor (BDNF) by at least 1.5-fold. Our results demonstrated that compounds isolated from T. formosana possess robust osteogenic potential, with the new compound, 1, also exhibiting the potential to enhance the bone formation process. We suggest that T. formosana and its isolated active compounds deserve further evaluation for development as anti-osteoporotic agents.


Assuntos
Calcificação Fisiológica/efeitos dos fármacos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Traqueófitas/química , Biomarcadores , Expressão Gênica , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo
20.
PLoS Genet ; 15(5): e1007895, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31116734

RESUMO

XX and XY fetal gonads are initially bipotential, poised between the ovary and testis fate. Multiple lines of evidence suggest that commitment to testis fate requires the repression of genes associated with ovary fate. It was previously shown that loss of CBX2, the subunit of the Polycomb Repressive Complex 1 (PRC1) that binds H3K27me3 and mediates silencing, leads to ovary development in XY mice and humans. While it had been proposed that CBX2 is an activator of the testis-determining gene Sry, we investigated the alternative possibility that CBX2 has a direct role as a repressor of the antagonistic ovary-promoting pathway. To investigate this possibility, we developed a quantitative genome-wide profile of the repressive histone mark H3K27me3 and its active counterpart H3K4me3 in isolated XY and XX gonadal supporting cells before and after sex determination. We show that testis and ovary sex-determining (SD) genes are bivalent before sex determination, providing insight into how the bipotential state of the gonad is established at the epigenetic level. After sex determination, many SD genes of the alternate pathway remain bivalent, possibly contributing to the ability of these cells to transdifferentiate even in adults. The finding that many genes in the Wnt signaling pathway were targeted for H3K27me3-mediated repression in Sertoli cells led us to test whether deletion of Wnt4 could rescue testis development in Cbx2 mutants. We show that Sry expression and testis development were rescued in XY Cbx2-/-;Wnt4-/- mice. Furthermore, we show that CBX2 directly binds the downstream Wnt signaler Lef1, an ovary-promoting gene that remains bivalent in Sertoli cells. Our results suggest that stabilization of the testis fate requires CBX2-mediated repression of bivalent ovary-determining genes, which would otherwise block testis development.


Assuntos
Epigênese Genética , Ovário/metabolismo , Complexo Repressor Polycomb 1/genética , Processos de Determinação Sexual , Testículo/metabolismo , Via de Sinalização Wnt/genética , Animais , Embrião de Mamíferos , Feminino , Fator 9 de Crescimento de Fibroblastos/genética , Fator 9 de Crescimento de Fibroblastos/metabolismo , Proteína Forkhead Box L2/genética , Proteína Forkhead Box L2/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Histonas/genética , Histonas/metabolismo , Humanos , Fator 1 de Ligação ao Facilitador Linfoide/genética , Fator 1 de Ligação ao Facilitador Linfoide/metabolismo , Masculino , Camundongos , Ovário/citologia , Ovário/crescimento & desenvolvimento , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Complexo Repressor Polycomb 1/deficiência , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Diferenciação Sexual , Testículo/citologia , Testículo/crescimento & desenvolvimento , Proteína Wnt4/genética , Proteína Wnt4/metabolismo
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