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BACKGROUND: Endocytosis is the process by which platelets incorporate extracellular molecules into their secretory granules. Endocytosis is mediated by the actin cytoskeleton in nucleated cells; however, the endocytic mechanisms in platelets are undefined. OBJECTIVES: To better understand platelet endocytosis, we studied gelsolin (Gsn), an actin-severing protein that promotes actin assembly. METHODS: Mouse platelets from Gsn-null (Gsn-/-) and wild-type (WT) controls were used. The uptake of fluorescent cargo molecules was compared as a measure of their endocytic efficiency. Receptor-mediated endocytosis was measured by the uptake of fibrinogen and transferrin; fluid-phase endocytosis was monitored by the uptake of fluorescent dextrans. RESULTS: Adenosine diphosphate (ADP)-stimulated WT platelets readily internalized both receptor-mediated and fluid-phase cargoes. In contrast, Gsn-/- platelets showed a severe defect in the endocytosis of both types of cargo. The treatment of WT platelets with the actin-disrupting drugs cytochalasin D and jasplakinolide also reduced endocytosis. Notably, the individual and combined effects of Gsn deletion and drug treatment were similar for both receptor-mediated and fluid-phase endocytosis, indicating that Gsn mediates endocytosis via its action on the actin cytoskeleton. CONCLUSION: Our study demonstrates that Gsn plays a key role in the uptake of bioactive mediators by platelets.
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Platelets are known for their indispensable role in hemostasis and thrombosis. However, alteration in platelet function due to oxidative stress is known to mediate various health complications, including cardiovascular diseases and other health complications. To date, several synthetic molecules have displayed antiplatelet activity; however, their uses are associated with bleeding and other adverse effects. The commercially available curcumin is generally a mixture of three curcuminoids: curcumin, demethoxycurcumin, and bisdemethoxycurcumin. Although crude curcumin is known to inhibit platelet aggregation, the effect of purified curcumin on platelet apoptosis, activation, and aggregation remains unclear. Therefore, in this study, curcumin was purified from a crude curcumin mixture and the effects of this preparation on the oxidative stress-induced platelet apoptosis and activation was evaluated. 2,2'-Azobis(2-methylpropionamidine) dihydrochloride (AAPH) compound was used as an inducer of oxidative stress. Purified curcumin restored AAPH-induced platelet apoptotic markers like reactive oxygen species, intracellular calcium level, mitochondrial membrane potential, cardiolipin peroxidation, cytochrome c release from mitochondria to the cytosol, and phosphatidyl serine externalization. Further, it inhibited the agonist-induced platelet activation and aggregation, demonstrating its antiplatelet activity. Western blot analysis confirms protective effect of the purified curcumin against oxidative stress-induced platelet apoptosis and activation via downregulation of MAPKs protein activation, including ASK1, JNK, and p-38. Together, these results suggest that the purified curcumin could be a potential therapeutic bioactive molecule to treat the oxidative stress-induced platelet activation, apoptosis, and associated complications.
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Apoptose , Plaquetas , Curcumina , MAP Quinase Quinase Quinase 5 , Estresse Oxidativo , Curcumina/farmacologia , Curcumina/análogos & derivados , Curcumina/química , Apoptose/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , MAP Quinase Quinase Quinase 5/metabolismo , Humanos , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Ativação Plaquetária/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacosRESUMO
Platelet transfusions are essential for managing bleeding and hemostatic dysfunction and could be expanded as a cell therapy due to the multifunctional role of platelets in various diseases. Creating these cell therapies will require modifying transfusable donor platelets to express therapeutic proteins. However, there are currently no appropriate methods for genetically modifying platelets collected from blood donors. Here, we describe an approach using platelet-optimized lipid nanoparticles containing mRNA (mRNA-LNP) to enable exogenous protein expression in human and rat platelets. Within the library of mRNA-LNP tested, exogenous protein expression did not require nor correlate with platelet activation. Transfected platelets retained hemostatic function and accumulated in regions of vascular damage after transfusion into rats with hemorrhagic shock. We expect this technology will expand the therapeutic potential of platelets.
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Plaquetas , Hemostáticos , Humanos , Ratos , Animais , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Plaquetas/metabolismo , Doadores de Sangue , Hemostáticos/metabolismoRESUMO
Becoming elderly is an intrinsic part of life, and the burden of disease increases with age. However, the early life migration experience and occupational hazards at the destination can lead to serious health problems later in life. This study aims to understand the association between early life migration and the health and risky behavior of elderly return migrants using data from the Kerala Migration Survey in 2018. The results of bivariate and multivariate analyses show that the majority of migrants return due to retirement and ill health at the average age of 51 and suffer from poor health and multiple diseases. More than half (55%) of elderly returnees reported poor health, and among them, 70% have at least one chronic disease. The early life migration experience and injuries at the destination are the main determinants of poor self-rated health and chronic disease. Furthermore, elderly return migrants have high-risk health behaviours such as smoking and alcohol consumption, as well as less access to health schemes. Despite some shortcomings, this study identifies the most vulnerable groups among the elderly and their health characteristics. This will help to promote healthy aging in Kerala, India, or areas with increasing numbers of elderly and return migrants around the world.
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Background and Objective: The molecular mechanisms that underpin platelet granule secretion remain poorly defined. Filamin A (FLNA) is an actin-crosslinking and signaling scaffold protein whose role in granule exocytosis has not been explored despite evidence that FLNA gene mutations confer platelet defects in humans. Methods and Results: Using platelets from platelet-specific conditional Flna-knockout mice, we showed that the loss of FLNA confers a severe defect in alpha (α)- and dense (δ)-granule exocytosis, as measured based on the release of platelet factor 4 (aka CXCL4) and adenosine triphosphate (ATP), respectively. This defect was observed following activation of both immunoreceptor tyrosine-based activation motif (ITAM) signaling by collagen-related peptide (CRP) and G protein-coupled receptor (GPCR) signaling by thrombin and the thromboxane mimetic U46619. CRP-induced spikes in intracellular calcium [Ca2+]i were impaired in FLNA-null platelets relative to controls, confirming that FLNA regulates ITAM-driven proximal signaling. In contrast, GPCR-mediated spikes in [Ca2+]i in response to thrombin and U46619 were unaffected by FLNA. Normal platelet secretion requires complexing of the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins synaptosomal-associated protein 23 (SNAP23) and syntaxin-11 (STX11). We determined that FLNA coimmunoprecipitates with both SNAP23 and STX11 upon platelet stimulation. Conclusion: FLNA regulates GPCR-driven platelet granule secretion and associates with SNAP23 and STX11 in an activation-dependent manner.
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BACKGROUND AND OBJECTIVE: The mechanisms underlying platelet granule release are not fully understood. The actin cytoskeleton serves as the platelet's structural framework that is remodeled upon platelet activation. Gelsolin is a calcium-dependent protein that severs and caps existing actin filaments although its role in modulating platelet granule exocytosis is unknown. METHODS: The hemostatic function of wild-type (WT) and gelsolin null (Gsn-/- ) mice was measured ex vivo by rotational thromboelastometry analysis of whole blood. Platelets were purified from WT and Gsn-/- mouse blood and activated with thrombin. Platelet aggregation was assessed by light-transmission aggregometry. Clot retraction was measured to assess outside-in integrin signaling. Adenosine triphosphate (ATP) release and surface P-selectin were measured as markers of dense- and α-granule secretion, respectively. RESULTS: The kinetics of agonist-induced aggregation, clot retraction, and ATP release were accelerated in Gsn-/- platelets relative to WT. However, levels of surface P-selectin were diminished in Gsn-/- platelets. ATP release was also accelerated in WT platelets pretreated with the actin-depolymerizing drug cytochalasin D, thus mimicking the kinetics observed in Gsn-/- platelets. Conversely, ATP release kinetics were normalized in Gsn-/- platelets treated with the actin polymerization agonist jasplakinolide. Rab27b and Munc13-4 are vesicle-priming proteins known to promote dense granule secretion. Co-immunoprecipitation indicates that the association between Rab27b and Munc13-4 is enhanced in Gsn-/- platelets. CONCLUSIONS: Gelsolin regulates the kinetics of hemostasis by modulating the platelet's actin cytoskeleton and the protein machinery of dense granule exocytosis.
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Actinas , Gelsolina , Camundongos , Animais , Gelsolina/metabolismo , Actinas/metabolismo , Selectina-P/metabolismo , Citoesqueleto de Actina/metabolismo , Plaquetas/metabolismo , Hemostasia , Agregação Plaquetária/fisiologia , Trifosfato de Adenosina/metabolismoRESUMO
Homeostasis between platelet production and clearance is essential for human health. A critical facet of the balance that facilitates platelet clearance from the circulation is apoptosis (programmed cell death). The precise cellular mechanisms that underpin platelet apoptosis are not defined. In nucleated cells, reorganization of the actin cytoskeleton is known to regulate platelet apoptosis. However, the role of the actin cytoskeleton in regulating apoptosis in platelets has not been extensively studied as they are anucleate and exhibit a distinctive physiology. Here, apoptosis was induced in washed human platelets using ABT-737, a BH3-mimetic drug. Mitochondrial depolarization was measured using the ratiometric dye JC-1; surface phosphatidylserine (PS) exposure was measured by annexin V binding; caspase-3 activation was measured by Western blotting. All three apoptotic markers were unaffected by the presence of either the actin depolymerizing drug cytochalasin D or the actin polymerizing drug jasplakinolide. Moreover, platelets were isolated from wild-type (WT) mice and mice deficient in gelsolin (Gsn), an actin-binding protein that is essential for normal cytoskeletal remodeling. In response to ABT-737, gelsolin-null (Gsn-/-) platelets initially showed accelerated PS exposure relative to WT platelets, however, both WT and Gsn-/- platelets exhibited similar levels of mitochondrial depolarization and caspase-3 activation in response to ABT-737. We conclude that ABT-737 induces established markers of platelet apoptosis in an actin-independent manner.
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Actinas , Gelsolina , Humanos , Camundongos , Animais , Caspase 3/metabolismo , Gelsolina/metabolismo , Actinas/metabolismo , Plaquetas/metabolismo , Apoptose/fisiologia , Fosfatidilserinas/metabolismo , Citoesqueleto de Actina/metabolismoRESUMO
Bioremediation itself is considered to be a cost effective soil clean-up technique and preferred over invasive physical and chemical treatments. Besides increasing efficiency, application of genetic engineering has led to reduction in the time duration required to achieve remediation, overcoming the so called 'Achilles heel' of Bioremediation. Omics technologies, namely genomics, transcriptomics, proteomics, and metabolomics, are being employed extensively to gain insights at genetic level. A wise synchronised application of these approaches can help scrutinize complex metabolic pathways, and molecular changes in response to heavy metal stress, and also its fate i.e., uptake, transport, sequestration and detoxification. In the present review, an account of some latest achievements made in the field is presented.
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Genômica , Proteômica , Biodegradação Ambiental , Engenharia Genética , Genômica/métodos , Metabolômica/métodos , Proteômica/métodosRESUMO
Bisphenol AF, an analogue of Bisphenol A, is an important raw material used in the production of plastic and rubber substances like plastic bottles and containers, toys, and medical supplies. Increased contamination of air, water, dust, and food with BPA/BPAF, poses an enormous threat to humans, globally. BPAF/BPA are endocrine-disrupting chemicals that mimic estrogen hormone, thus increasing the risks of various metabolic and chronic disorders. Exposure of human blood cells to BPA/BPAF induces oxidative stress and genotoxicity. However, its effects on platelets, which play central roles in hemostasis and thrombosis, are not well-documented. In this study, we demonstrate that BPAF induces RIPK1-inflammasome axis-mediated necroptosis in platelets, increasing procoagulant platelet levels in vivo and in vitro. We also show that BPAF-induced rise in procoagulant platelets worsens pulmonary thromboembolism in vivo. The elevated procoagulant platelets are shown to increase platelet-neutrophil/monocyte aggregates that mediate pathogenesis of CVD, thrombosis, and chronic inflammatory diseases. Our results demonstrate the toxic effects of BPAF on platelets and how it propagates the clinical complications by elevating procoagulant platelet numbers. Altogether, our study sends a cautionary message against extensive use of BPAF in the plastic and rubber industries, resulting in frequent human exposure to it, thus endangering platelet functions.
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Compostos Benzidrílicos/toxicidade , Plaquetas/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Necroptose/efeitos dos fármacos , Fenóis/toxicidade , Animais , Plaquetas/metabolismo , Feminino , Humanos , Inflamassomos/efeitos dos fármacos , Inflamassomos/metabolismo , Masculino , Camundongos , Embolia Pulmonar/fisiopatologia , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismoRESUMO
This study investigates the impact of Glomus mosseae on heavy metal(loid) (HM) uptake efficiency of pea (Pisum sativum L.) plants along with physiological and biochemical parameters. Plants were grown in soil spiked with HMs (Pb and As: 50 and 100 mg kg-1; Cd: 25 and 50 mg kg-1) and a multi-metal(loid) (Mm: Pb + Cd + As) combination, inoculated/non-inoculated with G. mosseae. A dose-dependent increase in HM accumulation was observed in plants upon harvest at 60 days. Plant growth, concentration of photosynthetic pigments, total nitrogen, and carbohydrates reduced, whereas enzymatic [catalase (CAT), superoxide dismutase (SOD), and ascorbate peroxidase (APX)] and non-enzymatic (proline and total phenolics) antioxidants increased upon HM stress. Inoculation with G. mosseae led to an increase in plant growth, concentration of photosynthetic pigments, carbohydrate, nitrogen, and defence antioxidants (whereas proline decreased) which was statistically significant (p ≤ 0.05). This symbiosis can be applied for onsite remediation of Pb and Cd contaminated soil by virtue of accumulation efficiency and adaptive response of pea plants inoculated with G. mosseae. Since the amount of HMs in edible parts exceeded the maximum permissible limits recommended by FAO/WHO, pea must not be cultivated in HM-contaminated soil for agricultural purpose due to associated toxicity. Novelty statement To our knowledge, phytoremediation potential of Pea in synchronization with Glomus mosseae has not been evaluated previously. This study highlights: ⢠Pea-AMF symbiosis can be applied for Pb and/or Cd phytoremediation. ⢠Target Hazard Quotient >1 for Pb, Cd and As; caution to food chain exposure required. ⢠Nonenzymatic (proline, TPC) and enzymatic (CAT, SOD, APX) antioxidants play a key role in ROS detoxification.
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Arsênio , Poluentes do Solo , Biodegradação Ambiental , Cádmio , Fungos , Chumbo , Pisum sativum , Raízes de Plantas/química , Solo , Poluentes do Solo/análise , SimbioseRESUMO
Curcumin, a major bioactive component of turmeric (Curcuma longa), is known for its multiple health benefits. Curcumin as such is a mixture of its analogs: bisdemethoxycurcumin (BDMC)-3%, and demethoxycurcumin (DMC)-17%. Although the effect of curcumin on platelets is documented, the effect of BDMC and DMC on platelets is less studied. Considering the indispensable role played by platelets in hemostasis, thrombosis, inflammation, and immunity, the present study evaluates the effect of curcumin, DMC and BDMC on platelet apoptosis. The components of curcumin were purified by silica-gel column chromatography. The purity and mass analysis of the purified curcuminoids was determined by RP-HPLC and LC-MS respectively. When analyzed for platelet apoptotic markers, only BDMC demonstrated increased incidence of platelet apoptotic markers including increase in intracellular Ca2+, decrease in ∆ψm, alteration in BCl-2 family proteins, the release of cytochrome c, caspase activation, and PS externalization via activation of ERK activation. ERK inhibitor PD98059 significantly alleviated BDMC induced decrease in ∆ψm, alteration in BCl-2, caspase-8 activation and PS externalization. Our results demonstrate that curcumin, DMC and BDMC differentially act on platelet in inducing apoptosis and the study highlights that the toxicity associated with curcumin therapy might be attributed to BDMC in the mammalian system.
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Plaquetas/efeitos dos fármacos , Diarileptanoides/toxicidade , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Plaquetas/metabolismo , Curcumina/toxicidade , HumanosRESUMO
Background: Bedside diagnostic ultrasound for traumatic pneumothorax is easy and reliable. However, the thoracic anatomical locations to be examined are debateable. We aimed to study the anatomical locations of blunt traumatic pneumothoraces as defined by chest CT scan to identify the areas that should be scanned while performing bedside diagnostic ultrasound. Methods: This is a retrospective analysis of a data collected for a previous study in blunt trauma patients at our hospital during a 4-year-period with CT confirmed pneumothoraces. The anatomical distribution of the pneumothoraces and their volume were analyzed. Advanced statistical analysis was performed using repeated measures logistic regression models. Results: Seven hundred three patients had a CT scan of the chest. Seventy-four patients (10.5%) were confirmed to have a pneumothorax. Only 64 were included in the study as they did not have a chest tube inserted before the CT scan. Twelve (18.8%) patients had bilateral pneumothorax. Seventy-six pneumothoraces were identified for which 41 patients had a right-sided pneumothorax and 35 patients had a left-sided pneumothorax. 95.1 % of the pneumothoraces detected on the right side were in the whole parasternal area with 75.6% seen in the lower parasternal region only. Similarly, 97.1 % of the pneumothoraces on the left side were seen in the whole parasternal area with 80% seen in the lower parasternal region only. Conclusions: The current study showed that air pockets of blunt traumatic pneumothoraces are mainly located at the parasternal regions especially in pneumothorax with small volume. We recommend a quick ultrasound scanning of the parasternal regions on both sides of the chest from proximal to distal as the appropriate technique for the detection of pneumothoraces in blunt trauma setting.
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Pneumotórax/diagnóstico , Traumatismos Torácicos/complicações , Ferimentos não Penetrantes/complicações , Adulto , Ar/análise , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Pneumotórax/fisiopatologia , Estudos Retrospectivos , Estatísticas não Paramétricas , Traumatismos Torácicos/diagnóstico , Traumatismos Torácicos/fisiopatologia , Tórax/anatomia & histologia , Tórax/fisiopatologia , Ferimentos não Penetrantes/diagnóstico , Ferimentos não Penetrantes/fisiopatologiaRESUMO
We report here the synthesis and thermotropic properties of novel short-core hockey stick-shaped liquid crystalline molecules based on the 1,3,4-thiadiazole core. Polar switching behavior is observed in the cybotactic nematic and smectic mesophases for the bent-core thiadiazole derivatives. The presence of the lateral methoxy moiety in the outer phenyl ring of the four-ring molecules facilitates the formation of spontaneous ordering in the nematic phase observed via X-ray diffraction measurements. Anomalous temperature dependence of spontaneous polarization on cooling is explained by the possible antiferroelectric packing of the molecules that require higher electric field for switching. The compounds exhibited a strong absorption band at â¼356 nm and a blue emission band at â¼445 nm with a good quantum yield of φf â¼0.39. The mega Stokes shift is observed and depends on the nature of the solvent.
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A pot study was conducted to assess the phytoremediation potential of Spinach plants along with their physiological and biochemical response when grown in soil contaminated with heavy metal(loid)s (HMs). Plants were grown under different doses of Pb, Cd and As; and their metal(loid) accumulation efficiency was studied upon harvest; expressed in terms of bioabsorption coefficient (BAC), bioconcentration factor (BCF) and translocation factor (TF). Results showed significant (pâ¯≤â¯0.05) difference in physiological and biochemical mechanisms of plants as detected through decrease in concentration of cellular constituents (pigments, carbohydrates, total nitrogen content); and increase in antioxidants (both enzymatic and non-enzymatic). Despite of accumulating high amount of HMs in tissues, no visible signs of toxicity were seen; and hence the efficient survival and defense mechanism shown by spinach plants conclude that they are a viable option to be used for phytoremediation of sites contaminated with Cd and Pb. Since the content of Cd and Pb in edible part was higher than safe limits prescribed by USEPA, the present investigation also highlights the ecological hazards that may result upon cultivation of spinach in contaminated soil for agricultural purpose; or its accidental exposure to food chain when grown for phytoremediation.
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Antioxidantes/metabolismo , Metaloides/toxicidade , Metais Pesados/toxicidade , Poluentes do Solo/toxicidade , Spinacia oleracea/efeitos dos fármacos , Agricultura , Biodegradação Ambiental , Ecologia , Metaloides/análise , Metais Pesados/análise , Solo/química , Poluentes do Solo/análise , Spinacia oleracea/crescimento & desenvolvimento , Spinacia oleracea/metabolismoRESUMO
A study was conducted to determine the effect of ethylenediaminetetraacetic acid (EDTA) on phytoextraction potential of radish and cabbage. Plant biomass, photosynthetic pigments, proline and phenolics were significantly affected by the accumulation of heavy metals (HM). The metal uptake potential was increased significantly by the application of EDTA. Target hazard quotient (THQ) associated with exposure of these contaminants to food chain was calculated. Agronomic interventions to increase mineral levels in crops often increases the leaf concentrations only, the mineral concentration in edible portions are not increased at desired level due to low mobility of Zn in phloem. Since the leaves of both these crops are edible and a component of staple vegetarian diet, biofortification through Zn present in soil and its solubilization and mobilization through chelators can be implemented. However in no such instance these crops should be consumed when grown on Pb contaminated soil due to associated hazards.
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Brassica/metabolismo , Ácido Edético/química , Inocuidade dos Alimentos , Metais Pesados/metabolismo , Raphanus/efeitos dos fármacos , Raphanus/metabolismo , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Biomassa , Brassica/efeitos dos fármacos , Metais Pesados/toxicidade , Medição de Risco , Solo/química , Poluentes do Solo/toxicidadeRESUMO
BACKGROUND: Periodontitis confers an increased risk for cardiovascular diseases, including thrombosis. However, the molecular mechanisms that potentially link periodontitis with thrombosis are undefined. Here we test the hypothesis that Gram-negative periodontal infection promotes pathological platelet activation and amplifies shape change. We focus specifically on lipopolysaccharide (LPS) signaling to platelets. METHODS: Platelets were isolated from blood samples and allowed to spread on coverslips in the presence or absence of LPS purified from the periodontal pathogen Porphyromonas gingivalis. Platelets were fixed and stained with Alexa-488-phalloidin to label the actin cytoskeleton. The degree of platelet spreading and shape change was quantified by confocal microscopy. In a translational pilot study, blood samples were obtained from human subjects exhibiting generalized severe periodontitis (SP) or healthy periodontium (HP). Rotational thromboelastometry was used to quantify the rate of clot formation via the intrinsic coagulation pathway. RESULTS: LPS-treated platelets exhibited significantly (P < 0.05) greater spreading and higher numbers of actin-rich filopodia (cell extensions) than controls. We also found that LPS stimulation of platelets promoted the activation of Cdc42, the small GTPase responsible for filopodia formation. Exposure of whole blood samples to LPS significantly (P < 0.05) reduced clotting times. Blood from SP patients clotted significantly (P < 0.05) more rapidly and exhibited shorter partial thromboplastin times compared with HP controls. CONCLUSIONS: This is the first study to suggest a mechanism by which LPS stimulation drives Cdc42 activation and platelet spreading. These data are consistent with the notion that periodontitis promotes accelerated clot formation and an increased risk of thrombosis.
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Plaquetas , Trombose , Humanos , Lipopolissacarídeos , Projetos Piloto , Porphyromonas gingivalisRESUMO
Approximately 15% of globally diagnosed breast cancers are designated as triple negative breast cancer (TNBC). In this study, we investigated the effect of the natural compound, Bis(2- ethyl hexyl) 1H-pyrrole-3,4-dicarboxylate (TCCP), purified from Tinospora cordifolia on MDA-MB-231, a TNBC cell line. The pro-apoptotic nature of TCCP on MDA-MB-231 was determined by assessing various apoptotic markers. ROS generation, intracellular calcium, mitochondrial membrane potential (ΔΨm), MPTP, cardiolipin peroxidation and caspase activity were determined fluorometrically. BAX, BCL-2, cytochrome c, caspases, and p53 protein expressions were determined by immunoblotting. Further, the effect of TCCP on DNA and cell death was determined by DNA fragmentation assay, annexin-V staining, and cell cycle analysis. TCCP treatment caused endogenous ROS generation, increase in intracellular calcium and phosphorylation of p53 in a concentration-dependent manner, which was reverted upon pre-treatment with pifithrin-µ. This led to the downstream altered expression of Bcl-2 and Bax proteins, mitochondrial membrane depolarization, MPTP, and cardiolipin peroxidation. TCCP induced cytochrome c release into the cytosol, caspase activation, ultimately resulting in DNA fragmentation. Further, induction of apoptosis and morphological alterations were evident from the phosphatidylserine externalization and increase in sub G1 population. The in vivo Ehrlich ascites tumor (EAT) mouse study revealed the effectiveness of TCCP in reducing the tumor burden and resulted in a ~2 fold increase in mice survival with minimal hepato-renal toxicity. Overall, TCCP was shown to be efficient in inducing ROS and mitochondrial-mediated apoptosis by restoring p53 activity in MDA-MB-231â¯cells and also induced EAT cell death in vivo thereby inhibiting tumor proliferation.
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Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Pirróis/química , Espécies Reativas de Oxigênio/metabolismo , Tinospora/química , Proteína Supressora de Tumor p53/metabolismo , Animais , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Fragmentação do DNA/efeitos dos fármacos , Feminino , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Mitocôndrias/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Taxa de Sobrevida , Tinospora/metabolismoRESUMO
Platelet hyperactivity is the hallmark of thrombosis and hemostasis disorders including atherosclerosis, diabetes, stroke, arthritis, and cancer causing significant mortality and morbidity. Therefore, regulating platelet hyperactivity is an ever growing interest. Very recently, basal autophagic process has been demonstrated to be essential for normal functioning of platelets. However, autophagy can be elevated above basal level under conditions like starvation, and how platelets respond in these settings remains to be elucidative. Therefore, in this study we demonstrate a substantial autophagy induction (above basal level) by starvation, which decreases platelet aggregation responses to various agonists. The decreased aggregation in starved platelets was restored in combination with autophagy inhibitors (3-methyladenine and NH4Cl) and acetate supplementation. Starved platelets also showed decreased calcium mobilization, granule release, and adhesive properties. Furthermore, ex vivo platelets obtained from starved rats showed increased autophagy markers and decreased aggregation responses to various agonists. Our results distinctly explain that enhanced autophagy and cellular energy depletion are the cause for decreased platelet activation and aggregation. The study emphasizes the cardinal role of starvation and autophagy in the management of diseases and disorders associated with platelet hyperactivity.
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Plaquetas/metabolismo , Agregação Plaquetária/fisiologia , Animais , Autofagia , Humanos , Ratos WistarRESUMO
Diabetes mellitus (DM) is a serious metabolic disorder affecting millions of people worldwide. The high rate of mortality and morbidity during DM is attributed to the increased atherothrombotic events due to platelet activation and apoptosis leading to macro and micro vascular occlusions. The platelet hyper-reactivity and apoptosis during DM is accounted for the accumulated reactive oxygen species (ROS) due to increased aldose reductase (AR) and NADPH oxidase (NOX) activities. Considering aspirin insensitivity in DM patients, new therapies targeting the underlying mechanism is urgently warranted. Berberine, a benzylisoquinoline alkaloids, from Chinese folk medicine has been demonstrated with several anti-diabetic effects. Therefore, we evaluated whether berberine inhibits high glucose potentiated platelet aggregation, apoptosis and further evaluated the mechanism of its action in platelets. Berberine was found to inhibit platelet aggregation, superoxide production via modulating AR, NOX, and glutathione reductase activities in high glucose (HG) treated platelets. Correlated with this, berberine inhibited, calcium release, ERK activation, α- and dense granule release and platelet adhesive properties. In addition, berberine inhibited p38-p53 mediated BAX activation, mitochondrial dysfunction and platelet apoptosis induced by HG. The platelet protective effect of berberine by inhibiting AR and NOX in high glucose-treated platelets suggest that berberine could be developed as a potential therapeutic molecule in the treating pathologies associated with DM.
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Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Arteriopatias Oclusivas/tratamento farmacológico , Berberina/farmacologia , Plaquetas/fisiologia , Diabetes Mellitus/tratamento farmacológico , Agregação Plaquetária/efeitos dos fármacos , Aldeído Redutase/metabolismo , Plaquetas/efeitos dos fármacos , Células Cultivadas , Glucose/metabolismo , Humanos , Medicina Tradicional Chinesa , NADPH Oxidases/metabolismo , Oxirredução , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Transdução de SinaisRESUMO
In the present study, the phytoremedation potential along with growth, physiological and biochemical response of tomato (Solanum lycopersicum) was assessed under heavy metal(loid) (HM) and arbuscular mycorrhizal fungus (AMF) amendment. Effect of AMF on uptake and accumulation of metal(loid)s was assessed and accumulation characteristics were expressed in terms of bioabsorption coefficient (BAC), bioconcentration factor (BCF), translocation factor (TLF) and transfer factor (TF). Results showed that AMF-inoculated plants showed not only a better growth, chlorophyll content, strengthened non-enzymatic and enzymatic defense mechanism, but also accumulated higher concentration of metal(loid)s. The correlation between biochemical and physiological parameters was significant at 0.01 level. A significant difference (p ≤ 0.001) in antioxidant enzyme activity was found on increasing metal(loid) dose and application of AMF. The accumulation of Cd and Pb in edible part exceeded the chronic reference dose stated by USEPA. The target hazard quotient (THQ) was >1 for Cd and Pb, whereas <1 for As. The study shows that tomato has good potential as Cd and Pb phytoremediator, hence must not be consumed when grown on Cd or Pb contaminated sites.