Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 43
Filtrar
1.
J Cell Mol Med ; 28(4): e18139, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38334198

RESUMO

Platelets assume a pivotal role in the cardiovascular diseases (CVDs). Thus, targeting platelet activation is imperative for mitigating CVDs. Ginkgetin (GK), from Ginkgo biloba L, renowned for its anticancer and neuroprotective properties, remains unexplored concerning its impact on platelet activation, particularly in humans. In this investigation, we delved into the intricate mechanisms through which GK influences human platelets. At low concentrations (0.5-1 µM), GK exhibited robust inhibition of collagen and arachidonic acid (AA)-induced platelet aggregation. Intriguingly, thrombin and U46619 remained impervious to GK's influence. GK's modulatory effect extended to ATP release, P-selectin expression, intracellular calcium ([Ca2+ ]i) levels and thromboxane A2 formation. It significantly curtailed the activation of various signaling cascades, encompassing phospholipase Cγ2 (PLCγ2)/protein kinase C (PKC), phosphoinositide 3-kinase/Akt/glycogen synthase kinase-3ß and mitogen-activated protein kinases. GK's antiplatelet effect was not reversed by SQ22536 (an adenylate cyclase inhibitor) or ODQ (a guanylate cyclase inhibitor), and GK had no effect on the phosphorylation of vasodilator-stimulated phosphoproteinSer157 or Ser239 . Moreover, neither cyclic AMP nor cyclic GMP levels were significantly increased after GK treatment. In mouse studies, GK notably extended occlusion time in mesenteric vessels, while sparing bleeding time. In conclusion, GK's profound impact on platelet activation, achieved through inhibiting PLCγ2-PKC cascade, culminates in the suppression of downstream signaling and, ultimately, the inhibition of platelet aggregation. These findings underscore the promising therapeutic potential of GK in the CVDs.


Assuntos
Biflavonoides , Nucleotídeos Cíclicos , Fosfolipases , Humanos , Animais , Camundongos , Nucleotídeos Cíclicos/metabolismo , Nucleotídeos Cíclicos/farmacologia , Fosfolipase C gama/metabolismo , Ácido Araquidônico/farmacologia , Ácido Araquidônico/metabolismo , Fosfolipases/metabolismo , Fosfolipases/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores da Agregação Plaquetária/farmacologia , Ativação Plaquetária , Plaquetas/metabolismo , Agregação Plaquetária , Proteína Quinase C/metabolismo , Fosforilação , Colágeno/metabolismo
2.
Int J Mol Sci ; 25(15)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39125689

RESUMO

Our study explores the role of cancer-derived extracellular exosomes (EXs), particularly focusing on collagen alpha-3 (VI; COL6A3), in facilitating tumor dissemination and metastasis in epithelial ovarian cancer (EOC). We found that COL6A3 is expressed in aggressive ES2 derivatives, SKOV3 overexpressing COL6A3 (SKOV3/COL6A3), and mesenchymal-type ovarian carcinoma stromal progenitor cells (MSC-OCSPCs), as well as their EXs, but not in less aggressive SKOV3 cells or ES2 cells with COL6A3 knockdown (ES2/shCOL6A3). High COL6A3 expression correlates with worse overall survival among EOC patients, as evidenced by TCGA and GEO data analysis. In vitro experiments showed that EXs from MSC-OCSPCs or SKOV3/COL6A3 cells significantly enhance invasion ability in ES2 or SKOV3/COL6A3 cells, respectively (both, p <0.001). In contrast, ES2 cells with ES2/shCOL6A3 EXs exhibited reduced invasion ability (p < 0.001). In vivo, the average disseminated tumor numbers in the peritoneal cavity were significantly greater in mice receiving intraperitoneally injected SKOV3/COL6A3 cells than in SKOV3 cells (p < 0.001). Furthermore, mice intravenously (IV) injected with SKOV3/COL6A3 cells and SKOV3/COL6A3-EXs showed increased lung colonization compared to mice injected with SKOV3 cells and PBS (p = 0.007) or SKOV3/COL6A3 cells and PBS (p = 0.039). Knockdown of COL6A3 or treatment with EX inhibitor GW4869 or rapamycin-abolished COL6A3-EXs may suppress the aggressiveness of EOC.


Assuntos
Carcinoma Epitelial do Ovário , Colágeno Tipo VI , Exossomos , Neoplasias Ovarianas , Exossomos/metabolismo , Exossomos/genética , Feminino , Carcinoma Epitelial do Ovário/patologia , Carcinoma Epitelial do Ovário/genética , Carcinoma Epitelial do Ovário/metabolismo , Humanos , Colágeno Tipo VI/metabolismo , Colágeno Tipo VI/genética , Animais , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Camundongos , Linhagem Celular Tumoral , Metástase Neoplásica , Invasividade Neoplásica , Regulação Neoplásica da Expressão Gênica , Camundongos Nus , Movimento Celular
3.
Int J Mol Sci ; 25(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38396774

RESUMO

Platelets assume a pivotal role in the pathogenesis of cardiovascular diseases (CVDs), emphasizing their significance in disease progression. Consequently, addressing CVDs necessitates a targeted approach focused on mitigating platelet activation. Eugenol, predominantly derived from clove oil, is recognized for its antibacterial, anticancer, and anti-inflammatory properties, rendering it a valuable medicinal agent. This investigation delves into the intricate mechanisms through which eugenol influences human platelets. At a low concentration of 2 µM, eugenol demonstrates inhibition of collagen and arachidonic acid (AA)-induced platelet aggregation. Notably, thrombin and U46619 remain unaffected by eugenol. Its modulatory effects extend to ATP release, P-selectin expression, and intracellular calcium levels ([Ca2+]i). Eugenol significantly inhibits various signaling cascades, including phospholipase Cγ2 (PLCγ2)/protein kinase C (PKC), phosphoinositide 3-kinase/Akt/glycogen synthase kinase-3ß, mitogen-activated protein kinases, and cytosolic phospholipase A2 (cPLA2)/thromboxane A2 (TxA2) formation induced by collagen. Eugenol selectively inhibited cPLA2/TxA2 phosphorylation induced by AA, not affecting p38 MAPK. In ADP-treated mice, eugenol reduced occluded lung vessels by platelet thrombi without extending bleeding time. In conclusion, eugenol exerts a potent inhibitory effect on platelet activation, achieved through the inhibition of the PLCγ2-PKC and cPLA2-TxA2 cascade, consequently suppressing platelet aggregation. These findings underscore the potential therapeutic applications of eugenol in CVDs.


Assuntos
Eugenol , Embolia Pulmonar , Humanos , Camundongos , Animais , Eugenol/farmacologia , Eugenol/uso terapêutico , Eugenol/metabolismo , Fosfolipase C gama/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Modelos Animais de Doenças , Ativação Plaquetária , Agregação Plaquetária , Plaquetas/metabolismo , Fosforilação , Proteína Quinase C/metabolismo , Tromboxano A2/metabolismo , Colágeno/metabolismo , Embolia Pulmonar/tratamento farmacológico , Embolia Pulmonar/metabolismo , Fosfolipases A2 Citosólicas/metabolismo
4.
Int J Mol Sci ; 23(11)2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35682568

RESUMO

Lipoteichoic acid (LTA) is a key cell wall component and virulence factor of Gram-positive bacteria. LTA contributes a major role in infection and it mediates inflammatory responses in the host. Rutaecarpine, an indolopyridoquinazolinone alkaloid isolated from Evodia rutaecarpa, has shown a variety of fascinating biological properties such as anti-thrombotic, anticancer, anti-obesity and thermoregulatory, vasorelaxing activity. It has also potent effects on the cardiovascular and endocrine systems. Herein, we investigated rutaecarpine's (Rut) anti-inflammatory effects in LTA-stimulated RAW macrophage cells. The Western blot and spectrophotometric results revealed that Rut inhibited the production of nitric oxide (NO) and the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and interleukin (IL)-1ß in the LTA-induced macrophage cells. Successively, our mechanistic studies publicized that Rut inhibited LTA-induced phosphorylation of mitogen-activated protein kinase (MAPK) including the extracellular signal-regulated kinase (ERK), and p38, but not c-Jun NH2-terminal kinase (JNK). In addition, the respective Western blot and confocal image analyses exhibited that Rut reserved nuclear transcription factor kappa-B (NF-κB) by hindering inhibitor of nuclear factor κB-α (IκBα) and NF-κB p65 phosphorylation and p65 nuclear translocation. These results indicate that Rut exhibits its anti-inflammatory effects mainly through attenuating NF-κB and ERK/p38 signaling pathways. Overall, this result suggests that Rut could be a potential therapeutic agent for the treatment of Gram-positive bacteria induced inflammatory diseases.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular , NF-kappa B , Animais , Anti-Inflamatórios/farmacologia , Ciclo-Oxigenase 2/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Alcaloides Indólicos/farmacologia , Lipopolissacarídeos/farmacologia , Camundongos , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Quinazolinas , Células RAW 264.7 , Ácidos Teicoicos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
5.
Molecules ; 27(16)2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-36014382

RESUMO

Inflammation is a major root of several diseases such as allergy, cancer, Alzheimer's, and several others, and the present state of existing drugs provoked researchers to search for new treatment strategies. Plants are regarded to be unique sources of active compounds holding pharmacological properties, and they offer novel designs in the development of therapeutic agents. Therefore, this study aimed to explore the anti-inflammatory mechanism of esculetin in lipoteichoic acid (LTA)-induced macrophage cells (RAW 264.7). The relative expression of inducible nitric oxide synthase (iNOS), nitric oxide (NO) production and COX-2 expression were intensified in LTA-induced RAW cells. The phosphorylation status of mitogen-activated protein kinases (extracellular signal-regulated kinase (ERK)1/2, p38 MAPK, and c-Jun N-terminal kinase (JNK)) and nuclear factor kappa B (NF-κB) p65 were detected by using Western blot assay. The nuclear translocation of p65 was assessed by confocal microscopic image analysis. Esculetin significantly and concentration-dependently inhibited LTA-induced NO production and iNOS expression, but not COX-2 expression, in RAW cells. Esculetin was not effective in LTA-induced MAPK molecules (ERK, p38 and JNK). However, esculetin recovered LTA-induced IκBα degradation and NF-κB p65 phosphorylation. Moreover, esculetin at a higher concentration of 20 µM evidently inhibited the nuclear translocation of NF-κB p65. At the same high concentration, esculetin augmented Nrf2 expression and decreased DPPH radical generation in RAW 264.7 cells. This study exhibits the value of esculetin for the treatment of LTA-induced inflammation by targeting NF-κB signaling pathways via its antioxidant properties.


Assuntos
Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B , Animais , Ciclo-Oxigenase 2/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7 , Transdução de Sinais
6.
Int J Mol Sci ; 19(4)2018 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-29642394

RESUMO

Traumatic brain injury (TBI) is one of the leading causes of mortality worldwide and leads to persistent cognitive, sensory, motor dysfunction, and emotional disorders. TBI-caused primary injury results in structural damage to brain tissues. Following the primary injury, secondary injuries which are accompanied by neuroinflammation, microglial activation, and additional cell death subsequently occur. Platonin, a cyanine photosensitizing dye, has been used to treat trauma, ulcers, and some types of acute inflammation. In the present study, the neuroprotective effects of platonin against TBI were explored in a controlled cortical impact (CCI) injury model in mice. Treatment with platonin (200 µg/kg) significantly reduced the neurological severity score, general locomotor activity, and anxiety-related behavior, and improved the rotarod performance of CCI-injured mice. In addition, platonin reduced lesion volumes, the expression of cleaved caspase-3, and microglial activation in TBI-insulted brains. Platonin also suppressed messenger (m)RNA levels of caspase-3, caspase-1, cyclooxygenase-2, tumor necrosis factor-α, interleukin-6, and interleukin-1ß. On the other hand, free radical production after TBI was obviously attenuated in platonin-treated mice. Treatment with platonin exhibited prominent neuroprotective properties against TBI in a CCI mouse model through its anti-inflammatory, anti-apoptotic, and anti-free radical capabilities. This evidence collectively indicates that platonin may be a potential therapeutic medicine for use with TBIs.


Assuntos
Anti-Inflamatórios/uso terapêutico , Lesões Encefálicas Traumáticas/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Tiazóis/uso terapêutico , Animais , Caspases/genética , Caspases/metabolismo , Córtex Cerebral/metabolismo , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Força da Mão , Interleucinas/genética , Interleucinas/metabolismo , Locomoção , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Microglia/patologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
7.
Int J Mol Sci ; 18(8)2017 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-28749412

RESUMO

A key focus in the field of drug discovery has been motivated by the neuroprotection of natural compounds. Cerebral ischemia is a multifaceted pathological process with a series of mechanisms, and a perspective for the development of neuroprotectants from traditional herbal medicine or natural products is a promising treatment for this disease. Natural compounds with the effects of anti-oxidation, anti-inflammation, anti-apoptosis, and neurofunctional regulation exhibit therapeutic effects on experimental ischemic brain injury. Conferring to the pharmacological mechanisms underlying neuroprotection, a study found that androgapholide, a diterpene lactone compound, exhibits varying degrees of neuroprotective activities in both in vitro and in vivo experimental models of stroke. The neuroprotective mechanisms of andrographolide are suggested as: (I) increasing nuclear factor E2-related factor 2-heme oxygenase (Nrf2-HO-1) expression through p38-mitogen activated protein kinase (MAPK) regulation, (II) inducing cerebral endothelial cells (CEC) apoptosis and caspase-3 activation, (III) down regulating Bax, inducible nitric oxide synthase (iNOS), and (IV) inhibiting hydroxyl radical (OH-) formation, and activating transcription factor NF-κB signaling pathways. Recently, several researchers have also been trying to unveil the principal mechanisms involved in the neuroprotective effects of andrographolide. Therefore, this review aims to summarize an overview on the neuroprotective effects of andrographolide and exemplifies the essential mechanisms involved. This paper can provide information that andrographolide drug discovery may be a promising strategy for the development of a novel class of neuroprotective drug.


Assuntos
Diterpenos/uso terapêutico , NF-kappa B/antagonistas & inibidores , Acidente Vascular Cerebral/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Diterpenos/química , Diterpenos/farmacologia , Humanos , NF-kappa B/metabolismo , Neuroproteção/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Acidente Vascular Cerebral/patologia
8.
J Biomed Sci ; 23: 26, 2016 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-26887315

RESUMO

BACKGROUND: Thrombus formation, a phenomenon primarily related to increased platelet activation, plays a key role in cardiovascular and cerebrovascular diseases. Although the established antiplatelet agents, such as aspirin and clopidogrel, have been shown to be beneficial in treating thromboembolic diseases, they have considerable limitations. Hence, the development of more effective and safe antithrombotic agents is necessary to satisfy a substantial unmet clinical need. In recent years, the favorable properties of imidazole-related drugs have prompted medicinal chemists to synthesize numerous novel therapeutic agents. The chemical structure of the benzimidazole backbone has proven antiplatelet properties. Moreover, synthetic oligosaccharides have exhibited antiplatelet properties. Therefore, we developed a new aldo-benzimidazole-derived oligosaccharide compound, M3BIM, for achieving a stronger antiplatelet effect than the drugs which are being used in clinical aspects. We investigated the effects of M3BIM on platelet activation ex vivo and its antithrombotic activity in vivo. RESULTS: M3BIM (10-50 µM) exhibited a more potent activity in inhibiting platelet aggregation stimulated by collagen than it did in inhibiting that stimulated by thrombin in washed human platelets. The M3BIM treatment revealed no cytotoxicity in zebrafish embryos, even at the highest concentration of 100 µM. In addition, M3BIM inhibited the phosphorylation of phospholipase Cγ2, protein kinase C (PKC), and mitogen-activated protein kinases (MAPKs; extracellular signal-regulated kinase 2 and c-Jun N-terminal kinase 1), and markedly reduced the ATP-release reaction and intracellular calcium mobilization in collagen-activated platelets. By contrast, M3BIM showed no effects on either collagen-induced p38 MAPK and Akt phosphorylation or phorbol 12, 13-dibutyrate-induced PKC activation and platelet aggregation. Moreover, the M3BIM treatment substantially prolonged the closure time in human whole blood, and increased the occlusion time in mesenteric microvessels and attenuated cerebral infarction in mice. For the study of anticoagulant activities, M3BIM showed no significant effects in the prolongation of activated partial thromboplastin time and prothrombin time in mice. CONCLUSION: The findings of our study suggest that M3BIM is a potential therapeutic agent for preventing or treating thromboembolic disorders.


Assuntos
Benzimidazóis , Plaquetas/metabolismo , Agregação Plaquetária/efeitos dos fármacos , Tromboembolia/tratamento farmacológico , Trissacarídeos , Animais , Benzimidazóis/química , Benzimidazóis/farmacologia , Plaquetas/patologia , Humanos , Camundongos , Tromboembolia/metabolismo , Tromboembolia/patologia , Trissacarídeos/química , Trissacarídeos/farmacologia , Peixe-Zebra
9.
ScientificWorldJournal ; 2014: 686109, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25140341

RESUMO

In this study, the neuroprotective effect of an extract of Antrodia camphorata (A. camphorata), a fungus commonly used in Chinese folk medicine for treatment of viral hepatitis and cancer, alone or in combination with aspirin was investigated in a rat embolic stroke model. An ischemic stroke was induced in rats by a selective occlusion of the middle cerebral artery (MCA) with whole blood clots and then orally treated with A. camphorata (0.25 and 0.75 g/kg/day) alone and combined with aspirin (5 mg/kg/day). Sixty days later, the brains were removed, sectioned, and stained with triphenyltetrazolium chloride and analysed by a commercial image processing software program. Brain infarct volume, neurobehavioral score, cerebral blood perfusion, and subarachnoid and intracerebral hemorrhage incidence were perceived. In addition, potential bleeding side effect of the combinative therapy was assessed by measuring hemoglobin (Hb) content during intracerebral hemorrhage and gastric bleeding, prothrombin time (PT), and occlusion time (OT) after oral administration. Posttreatment with high dose A. camphorata significantly reduced infarct volume and improved neurobehavioral score (P < 0.05). Since A. camphorata alone or with aspirin did not alter the Hb level, this treatment is safe and does not cause hemorrhagic incident. Remarkably, the combination of A. camphorata and aspirin did not show a significant effect on the bleeding time, PT and OT increase suggesting that A. camphorata may have the neuroprotective effect without the prolongation of bleeding time or coagulation time. From these observations, we suggest that combinative therapy of A. camphorata and aspirin might offer enhanced neuroprotective efficacies without increasing side effects.


Assuntos
Antrodia/química , Aspirina/uso terapêutico , Encéfalo/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Animais , Aspirina/administração & dosagem , Aspirina/efeitos adversos , Encéfalo/patologia , Quimioterapia Combinada , Hemoglobinas/metabolismo , Hemorragia/induzido quimicamente , Masculino , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/efeitos adversos , Fármacos Neuroprotetores/isolamento & purificação , Tempo de Protrombina , Ratos Wistar , Acidente Vascular Cerebral/complicações
10.
Acta Cardiol Sin ; 30(4): 308-15, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27122804

RESUMO

BACKGROUND: Aberrant vascular smooth muscle cell (VSMC) proliferation and cerebral endothelial cell (CEC) dysfunction contribute significantly in the pathogenesis of cardiovascular diseases. Therefore, inhibition of these cellular events would be by candidate agents for treating these diseases. In the present study, the mechanism of anti-proliferative and anti-inflammatory effects of andrographolides, a novel nuclear factor-κB inhibitor, was investigated in VSMC and CEC cells. METHODS: VSMCs and CECs were isolated from rat artery and mouse brain, respectively, and cultured before experimentation. The effect of andro on platelet-derived growth factor-BB (PDGF-BB) induced VSMC cell proliferation was evaluated by cell number, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The expression of extracellular signal regulated kinase 1/2 (ERK1/2), proliferating cell nuclear antigen (PCNA), and the effects on lipopolysaccharide (LPS)-induced inducible nitric oxide synthase (iNOS) and, cyclooxygenase-2 (COX2) were detected by Western blotting. RESULTS: Andro significantly inhibited PDGF-BB (10 ng/ml) induced cell proliferation in a concentration (20-100 µM) dependent manner, which may be due to reducing the expression of ERK1/2, and by inhibiting the expression of PCNA. Andro also remarkably diminished LPS-induced iNOS and COX2 expression. CONCLUSIONS: The results of this study suggested that the effects of andro against VSMCs proliferation and CECs dysfunction may represent a promising approach for treatment of vascular diseases. KEY WORDS: Andrographolide; CECs; COX2/iNOS; ERK/PCNA; LPS; PDGF-BB; VSMCs.

11.
Biomedicines ; 12(8)2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39200154

RESUMO

BACKGROUND: Platelets, a type of anucleated cell, play a crucial role in cardiovascular diseases (CVDs). Therefore, targeting platelet activation is essential for mitigating CVDs. Endogenous agonists, such as collagen, activate platelets by initiating signal transduction through specific platelet receptors, leading to platelet aggregation. Eugenol, primarily sourced from clove oil, is known for its antibacterial, anticancer, and anti-inflammatory properties, making it a valuable medicinal agent. In our previous study, eugenol was shown to inhibit platelet aggregation induced by collagen and arachidonic acid. We concluded that eugenol exerts a potent inhibitory effect on platelet activation by targeting the PLCγ2-PKC and cPLA2-TxA2 pathways, thereby suppressing platelet aggregation. In our current study, we found that eugenol significantly inhibits NF-κB activation. This led us to investigate the relationship between the NF-κB and cPLA2 pathways to elucidate how eugenol suppresses platelet activation. METHODS: In this study, we prepared platelet suspensions from the blood of healthy human donors to evaluate the inhibitory mechanisms of eugenol on platelet activation. We utilized immunoblotting and confocal microscopy to analyze these mechanisms in detail. Additionally, we assessed the anti-thrombotic effect of eugenol by observing fluorescein-induced platelet plug formation in the mesenteric microvessels of mice. RESULTS: For immunoblotting and confocal microscopy studies, eugenol significantly inhibited NF-κB-mediated signaling events stimulated by collagen in human platelets. Specifically, it reduced the phosphorylation of IKK and p65 and prevented the degradation of IκBα. Additionally, CAY10502, a cPLA2 inhibitor, significantly reduced NF-κB-mediated signaling events. In contrast, BAY11-7082, an IKK inhibitor, did not affect collagen-stimulated cPLA2 phosphorylation. These findings suggest that cPLA2 acts as an upstream regulator of NF-κB activation during platelet activation. Furthermore, both BAY11-7082 and CAY10502 significantly reduced the collagen-induced rise in intracellular calcium levels. In the animal study, eugenol demonstrated potential as an anti-thrombotic agent by significantly reducing platelet plug formation in fluorescein-irradiated mouse mesenteric microvessels. CONCLUSION: Our study uncovered a novel pathway in platelet activation involving the cPLA2-NF-κB axis, which plays a key role in the antiplatelet effects of eugenol. These findings suggest that eugenol could serve as a valuable and potent prophylactic or therapeutic option for arterial thrombosis.

12.
Antioxidants (Basel) ; 13(8)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39199147

RESUMO

Traumatic brain injury (TBI) is a significant cause of morbidity and mortality worldwide, and its pathophysiology is characterized by oxidative stress and inflammation. Despite extensive research, effective treatments for TBI remain elusive. Recent studies highlighted the critical interplay between TBI and circadian rhythms, but the detailed regulation remains largely unknown. Motivated by the observed sustained decrease in Rev-erbα after TBI, we aimed to understand the critical role of Rev-erbα in the pathophysiology of TBI and determine its feasibility as a therapeutic target. Using a mouse model of TBI, we observed that TBI significantly downregulates Rev-erbα levels, exacerbating inflammatory and oxidative stress pathways. The regulation of Rev-erbα with either the pharmacological activator or inhibitor bidirectionally modulated inflammatory and oxidative events, which in turn influenced neurobehavioral outcomes, highlighting the protein's protective role. Mechanistically, Rev-erbα influences the expression of key oxidative stress and inflammatory regulatory genes. A reduction in Rev-erbα following TBI likely contributes to increased oxidative damage and inflammation, creating a detrimental environment for neuronal survival and recovery which could be reversed via the pharmacological activation of Rev-erbα. Our findings highlight the therapeutic potential of targeting Rev-erbα to mitigate TBI-induced damage and improve outcomes, especially in TBI-susceptible populations with disrupted circadian regulation.

13.
Phytother Res ; 27(11): 1671-7, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23292890

RESUMO

Andrographolide, a novel nuclear factor-κB (NF-κB) inhibitor, is isolated from the leaves of Andrographis paniculata. Platelet activation is relevant to a variety of coronary heart diseases. Our recent studies revealed that andrographolide possesses potent antiplatelet activity by inhibition of the p38 MAPK/(●) HO-NF-κB-ERK2 cascade. Although platelets are anucleated cells, apoptotic machinery apparatus recently has been found to regulate platelet activation and limit platelet lifespan. Therefore, we further investigated the regulatory effects of andrographolide on platelet apoptotic events. In this study, apoptotic signaling events for caspase-3, -8, and Bid were time (10-60 min)- and dose (25-100 µΜ)-dependently activated by andrographolide in human platelets. Andrographolide could also disrupt mitrochondrial membrane potential. In addition, caspase-8 inhibitor (z-IETD-fmk, 50 µΜ) was found to reverse andrographolide-induced caspase-8 activation, whereas the antagonistic anti-Fas receptor (ZB4, 500 ng/mL) and anti-tumor necrosis factor-R1 (H398, 10 µg/mL) monoclonal antibodies did not. In conclusion, this study for the first time demonstrated that andrographolide might limit platelet lifespan by initiating the caspase-8-dependent extrinsic apoptotic pathway, in spite of no direct evidence that death receptors are involved in this process proved. Overall, the various medicinal properties of andrographolide suggest its potential value in treating patients with thromboembolic disorders.


Assuntos
Apoptose/efeitos dos fármacos , Plaquetas/efeitos dos fármacos , Diterpenos/farmacologia , Andrographis/química , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Plaquetas/citologia , Caspase 3/metabolismo , Caspase 8/metabolismo , Relação Dose-Resposta a Droga , Humanos , Potencial da Membrana Mitocondrial , Folhas de Planta/química , Ativação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
14.
Pharm Biol ; 51(9): 1150-7, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23930775

RESUMO

CONTEXT: Andrographolide, extracted from the leaves of Andrographis paniculata (Burm. f.) Nees (Acanthaceae), is a labdane diterpene lactone. It is widely reported to possess anti-inflammatory and antitumorigenic activities. Cerebral endothelial cells (CECs) play a crucial role in supporting the integrity and the function of the blood-brain barrier (BBB). However, no data are available concerning the effects of andrographolide in CECs. The aim of this study was to examine the detailed mechanisms of andrographolide on CECs. OBJECTIVE: This study investigated a novel bioactivity of andrographolide on cerebral ischemia/reperfusion-induced brain injury. MATERIALS AND METHODS: CECs were treated with andrographolide (20-100 µΜ) for the indicated times (0-24 h). After the reactions, cell survival rate and cytotoxicity were tested by the MTT assay and the lactate dehydrogenase (LDH) test, respectively. Western blotting was used to detect caspase-3 expression. In addition, analysis of cell cycle and apoptosis using PI staining and annexin V-FITC/PI labeling, respectively, was performed by flow cytometry. We also investigated the effect of andrographolide on middle cerebral artery occlusion (MCAO)/reperfusion-induced brain injury in a rat model. RESULTS: In the present study, we found that andrographolide (50-100 µΜ) markedly inhibited CEC growth according to an MTT assay and caused CEC damage according to a LDH test. Our data also revealed that andrographolide (50 µM) induced CEC apoptosis and caspase-3 activation as respectively detected by PI/annexin-V double staining and western blotting. Moreover, andrographolide arrested the CEC cell cycle at the G0/G1 phase by PI staining. In addition, andrographolide (5 mg/kg) caused deterioration of MCAO/reperfusion-induced brain injury in a rat model. CONCLUSIONS: These data suggest that andrographolide may disrupt BBB integrity, thereby deteriorating MCAO/reperfusion-induced brain injury, which are, in part, associated with its capacity to arrest cell-cycle and induce CEC apoptosis.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Apoptose/efeitos dos fármacos , Ventrículos Cerebrais/efeitos dos fármacos , Diterpenos/efeitos adversos , Endotélio Vascular/efeitos dos fármacos , Infarto da Artéria Cerebral Média/fisiopatologia , Traumatismo por Reperfusão/induzido quimicamente , Andrographis/química , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/enzimologia , Caspase 3/química , Caspase 3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Ventrículos Cerebrais/irrigação sanguínea , Ventrículos Cerebrais/citologia , Ventrículos Cerebrais/enzimologia , Endotélio Vascular/citologia , Endotélio Vascular/enzimologia , Ativação Enzimática/efeitos dos fármacos , Masculino , Camundongos , Folhas de Planta/química , Ratos , Ratos Wistar , Traumatismo por Reperfusão/enzimologia , Traumatismo por Reperfusão/etiologia , Fase de Repouso do Ciclo Celular/efeitos dos fármacos
15.
Antioxidants (Basel) ; 12(2)2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36829776

RESUMO

The incidence of traumatic brain injury (TBI) increases dramatically with advanced age and accumulating evidence indicates that age is one of the important predictors of an unfavorable prognosis after brain trauma. Unfortunately, thus far, evidence-based effective therapeutics for geriatric TBI is limited. By using middle-aged animals, we first confirm that there is an age-related change in TBI susceptibility manifested by increased inflammatory events, neuronal death and impaired functional outcomes in motor and cognitive behaviors. Since thyroid hormones function as endogenous regulators of oxidative stress, we postulate that age-related thyroid dysfunction could be a crucial pathology in the increased TBI severity. By surgically removing the thyroid glands, which recapitulates the age-related increase in TBI-susceptible phenotypes, we provide direct evidence showing that endogenous thyroid hormone-dependent compensatory regulation of antioxidant events modulates individual TBI susceptibility, which is abolished in aged or thyroidectomized individuals. The antioxidant capacity of melatonin is well-known, and we found acute melatonin treatment but not liothyronine (T3) supplementation improved the TBI-susceptible phenotypes of oxidative stress, excitotoxic neuronal loss and promotes functional recovery in the aged individuals with thyroid dysfunction. Our study suggests that monitoring thyroid function and acute administration of melatonin could be feasible therapeutics in the management of geriatric-TBI in clinic.

16.
Life Sci ; 326: 121791, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37211346

RESUMO

AIMS: Platelet activation plays a central role in arterial thrombosis. Platelets are activated by adhesive proteins (i.e., collagen) or soluble agonists (i.e., thrombin), the respective receptor-specific signaling cause inside-out signaling, leading to the binding of fibrinogen to integrin αIIbß3. This binding triggers outside-in signaling, resulting in platelet aggregation. Garcinol, a polyisoprenylated benzophenone, is extracted from the fruit rind of Garcinia indica. Although garcinol exhibits considerable bioactivities, few studies have investigated the effect of garcinol on platelet activation. MAIN METHODS: Aggregometry, immunoblotting, flow cytometer, confocal microscopic analysis, fibrin clot retraction, animal studies such as fluorescein-induced platelet plug formation in mesenteric microvessels, acute pulmonary thromboembolism, and tail bleeding time were performed in this study. KEY FINDINGS: This study indicates that garcinol inhibited platelet aggregation stimulated by collagen, thrombin, arachidonic acid, and U46619. Garcinol reduced integrin αIIbß3 inside-out signaling, including ATP release; cytosolic Ca2+ mobilization; P-selectin expression; and Syk, PLCγ2/PKC, PI3K/Akt/GSK3ß, MAPKs, and NF-κB activation stimulated by collagen. Garcinol directly inhibited integrin αIIbß3 activation by interfering with FITC-PAC-1 and FITC-triflavin by collagen. Additionally, garcinol affected integrin αIIbß3-mediated outside-in signaling, such as decreasing platelet adhesion and the single-platelet spreading area; suppressing integrin ß3, Src, FAK, and Syk phosphorylation on immobilized fibrinogen; and inhibiting thrombin-stimulated fibrin clot retraction. Garcinol substantially reduced mortality caused by pulmonary thromboembolism and prolonged the occlusion time of thrombotic platelet plug formation without extending bleeding time in mice. SIGNIFICANCE: This study identified that garcinol, a novel antithrombotic agent, acts as a naturally occurring integrin αIIbß3 inhibitor.


Assuntos
Embolia Pulmonar , Trombose , Humanos , Camundongos , Animais , Plaquetas/metabolismo , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Fluoresceína-5-Isotiocianato/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Trombina/metabolismo , Ativação Plaquetária , Agregação Plaquetária , Trombose/metabolismo , Fosforilação , Colágeno/metabolismo , Fibrinogênio/metabolismo , Embolia Pulmonar/metabolismo
17.
Heliyon ; 9(10): e20286, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37767484

RESUMO

Platelets play a vital role in the formation of dangerous arterial thrombosis. Platelets are activated by adhesive proteins or soluble agonists through their specific receptors. The receptor-mediated signaling pathways lead to common signaling events, which result in shape changes and inside-out signaling, leading fibrinogen binding to glycoprotein IIb/IIIa complex (integrin αIIbß3). This interaction initiates integrin αIIbß3-mediated outside-in signaling, subsequently culminating in granule secretion and aggregation. Myricetin is a flavonoid that occurs in a variety of plants. Although myricetin has been demonstrated to have several bioactive properties, its role in platelet activation has not been extensively studied. The present study demonstrated the ability of myricetin to inhibit platelet aggregation stimulated by collagen, thrombin, and U46619. Myricetin reduced the ATP-release, cytosolic Ca2+ mobilization, and P-selectin expression and the activation of PLCγ2/PKC, PI3K/Akt/GSK3ß, and MAPK. Myricetin exerted a direct inhibitory effect on the activation of integrin αIIbß3 by disrupting the binding between FITC-PAC-1 and the integrin. Moreover, myricetin suppressed integrin αIIbß3-mediated outside-in signaling, such as integrin ß3, Src, and Syk phosphorylation on immobilized fibrinogen. In animal studies, myricetin significantly prolonged the occlusion time of thrombotic platelet plug formation in mesenteric microvessels without extending bleeding time. This study concludes that myricetin is a natural integrin αIIbß3 inhibitor and a novel antithrombotic agent.

18.
Chin Med ; 18(1): 71, 2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-37301823

RESUMO

BACKGROUND: Platelets play a crucial role in cardiovascular diseases (CVDs) and are activated by endogenous agonists like collagen. These agonists initiate signal transduction through specific platelet receptors, resulting in platelet aggregation. Glabridin, a prenylated isoflavonoid found in licorice root, is known for its significance in metabolic abnormalities. Glabridin has been observed to inhibit collagen-induced platelet aggregation, but the precise mechanisms, specifically concerning NF-κB activation and integrin αIIbß3 signaling, are not yet fully understood. METHODS: In this study, platelet suspensions were prepared from healthy human blood donors, and the aggregation ability was observed using a lumi-aggregometer. The inhibitory mechanisms of glabridin in human platelets were evaluated through immunoblotting and confocal microscopy. The anti-thrombotic effects of glabridin were assessed by histological analysis of lung sections in acute pulmonary thromboembolism and by examining fluorescein-induced platelet plug formation in mesenteric microvessels in mice. RESULTS: Glabridin inhibited integrin αIIbß3 inside-out signals such as Lyn, Fyn, Syk, and integrin ß3 activation and NF-κB-mediated signal events, with similar potency to classical inhibitors BAY11-7082 and Ro106-9920. Glabridin and BAY11-7082 inhibited IKK, IκBα, and p65 phosphorylation and reversed IκBα degradation, while Ro106-9920 only reduced p65 phosphorylation and reversed IκBα degradation. BAY11-7082 reduced Lyn, Fyn, Syk, integrin ß3, phospholipase Cγ2 and protein kinase C activation. Glabridin reduced platelet plug formation in mesenteric microvessels and occluded vessels in thromboembolic lungs of mice. CONCLUSION: Our study revealed a new pathway for activating integrin αIIbß3 inside-out signals and NF-κB, which contributes to the antiplatelet aggregation effect of glabridin. Glabridin could be a valuable prophylactic or clinical treatment option for CVDs.

19.
Am J Cancer Res ; 12(11): 5325-5341, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36504889

RESUMO

Aberrant CpG-island methylation affects ovarian cancer progression. The promotor methylation changes at tumor suppressive genes in ovarian cancer stromal progenitor cells (OCSPCs) and epithelial ovarian cancer (EOC) tissues and their clinical implication remains unexplored. We systemically analyzed the promoter methylation status of 40 tumor suppressor genes (TSGs) associated with cancer in paired epithelial-like and mesenchymal-like OCSPCs and ovarian cancer cells by methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA). The effect of DNA methylation on gene expression was confirmed using qRT-PCR. The differential frequencies of TSGs' promoter methylation among matched epithelial-like or mesenchymal-like OCSPCs from tissues and ascites and ovarian cancer tissues were further validated in cancer tissues and correlated with clinicopathological features and survival outcomes of patients. According to the promoter methylation frequencies of the 40 TSGs, promoters of RASSF1A were the only significantly hypomethylated in epithelial-like OCSPCs from tissues than those from ascites and bulk tumor cells (0% vs 38% vs 45%, P=0.039 by Fisher's exact test). The most frequencies at promotor hypermethylation of TSGs in mesenchymal-like OCSPCs from ascites which processed aggressiveness were CDKN2B (73%) followed by CCND2 (45%) and RASSF1A (45%). Forty-three percent (47/110) of RASSF1A and 45% of CCND2 were validated as a frequently hypermethylated gene in an independent set of 110 EOC tissues in contrast to none (0/60) and 12% (10/60) of benign ovarian cysts (both P<0.001). Functional experiments revealed overexpression of CCND2 or CDKN2B in MSc-OCSPCs decreases EMT, invasion, and spheroid formation in EOC, and abolishes DNMT1 and COL6A3 expression. However, for the expected 5-year overall survival (OS) for patients with methylated RASSF1A, CCND2, and CDKN2B, only RASSF1A was significantly worse than those without methylated RASSF1A (56% vs 80%, p=0.022). Taken together, overexpression of CCND2 and CDKN2B decreased the aggressiveness of mesenchymal-like OCSPCs from ascites which may represent a potential therapeutic target for EOC. Promotor hypomethylation at RASSF1A in OCSPCs from EOC tissues and changes to hypermethylation of EOC and OCSPCs from ascites could predict poor survival outcomes for EOC patients compared to without those changes of CCND2 and CDKN2B.

20.
Am J Cancer Res ; 12(4): 1686-1706, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35530273

RESUMO

Ovarian clear cell cancer stem-like/spheroid cells (OCCCSCs) were associated with recurrence, metastasis, and chemoresistance in ovarian clear cell carcinoma (OCCC). We evaluated the anti-tumor effects of 5-aza-2-deoxycytidine (5-aza-dC) combined with everolimus (RAD001) on human OCCC. We investigated parental OCCCSCs and paclitaxel-resistant cell lines derived from OCCCSCs in vitro and in vivo. A Western blot analysis showed that the 5-aza-dC and RAD001 combination therapy was associated with the COL6A3-AKT-mTOR pathway. The OCCCSCs expressed high levels of stemness markers: CD117, ALDH1, NANOG, OCT4, and CD133. The 5-aza-dC and RAD001 combination inhibited proliferation and survival with up to 100-fold more potency in OCCCSCs compared to OCCC cells. This combination showed significant anti-tumor activity; it preferentially diminished OCCCSC stemness levels and spheroid numbers in vitro. Limiting dilution assays showed that OCCCSCs possessed tumor-initiating capacity. The 5-aza-dC and RAD001 combination significantly enhanced the inhibition of tumor growth compared to the 5-aza-dC or RAD001 alone. OCCCSCs showed higher expression levels of COL6A3, phospho-AKT, phospho-mTOR, and phospho-Rictor compared to OCCCs. Silencing COL6A3 or abolishing the phospho-AKT-mTOR-Rictor pathway with 5-aza-dC and RAD001 treatment further enhanced OCCCSC apoptosis and reduced OCCCSC stemness. In conclusion, 5-aza-dC combined with RAD001 effectively controlled OCCC and OCCCSC growth by inhibiting the COL6A3-AKT-mTOR pathway.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA