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1.
Biochem Biophys Res Commun ; 491(1): 183-191, 2017 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-28712866

RESUMO

Cell-free hemoglobin (Hb), a well-known marker of intravascular hemolysis, is eventually oxidized to methemoglobin (MtHb). Elevated levels of MtHb have been noted, alongside depleted levels of platelets, in several hemolytic diseases. The current study aims to probe the possible role of MtHb in platelet death, based on the facts that it is a pro-inflammatory and pro-apoptotic agent, as well as the sensitive nature of platelets and their tendency to undergo apoptosis under oxidative stress. An attempt is made to establish the link between hemolysis and thrombocytopenia, by deciphering the underlying molecular signaling pathways. The results of this study demonstrate that MtHb, not Hb exerts oxidative stress on platelets, which triggers their death via ROS-mediated mitochondrial apoptotic pathway. It was further established that the MtHb-induced platelet apoptotic events mediate through JNK and p38 MAPK activation. Thus, the study presents a mechanistic insight into the previous studies that reported the incidence of thrombocytopenia in hemolytic diseases. This study highlights the fate of platelets in intravascular hemolytic conditions, which demands the need for a specific treatment strategy considering the risks associated with thrombocytopenia during severe hemolytic diseases.


Assuntos
Apoptose/fisiologia , Plaquetas/fisiologia , MAP Quinase Quinase 7/metabolismo , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Apoptose/efeitos dos fármacos , Plaquetas/efeitos dos fármacos , Sistema Livre de Células/química , Células Cultivadas , Ativação Enzimática/efeitos dos fármacos , Humanos , Metemoglobina/farmacologia , Mitocôndrias/efeitos dos fármacos , Proteínas Mitocondriais/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia
2.
Toxicol Appl Pharmacol ; 334: 167-179, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28911973

RESUMO

Chronic hyperglycemia is one of the characteristic conditions associated with Diabetes Mellitus (DM), which often exerts deleterious effects on erythrocyte morphology and hemodynamic properties leading to anemia and diabetes-associated vascular complications. High glucose-induced over production of reactive oxygen species (ROS) can alter the blood cell metabolism and biochemical functions subsequently causing eryptosis (red blood cell death), yet another complication of concern in DM. Therefore, blocking high glucose-induced oxidative damage and subsequent eryptosis is of high importance in the better management of DM and associated vascular complications. In this study, we synthesized an oxolane derivative 1-(2,2-dimethyltetrahydrofuro[2,3][1,3]dioxol-5-yl)ethane-1,2-diol (DMTD), and demonstrated its efficacy to mitigate hyperglycemia-induced ROS generation and subsequent eryptosis. We showed that DMTD effectively inhibits high glucose-induced ROS generation, intracellular calcium levels, phosphaditylserine (PS) scrambling, calpain and band 3 activation, LDH leakage, protein glycation and lipid peroxidation, meanwhile enhances the antioxidant indices, osmotic fragility and Na+/K+-ATPase activity in erythrocytes. DMTD dose dependently decreased the glycated hemoglobin level and enhances the glucose utilization by erythrocytes in vitro. Further, DMTD alleviated the increase in ROS production, intracellular Ca2+ level and PS externalization in the erythrocytes of human diabetic subjects and enhanced the Na+/K+-ATPase activity. Taken together, the synthesized oxolane derivative DMTD could be a novel synthetic inhibitor of high glucose-induced oxidative stress and eryptosis. Considering the present results DMTD could be a potential therapeutic to treat DM and associated complications and open new avenues in developing synthetic therapeutic targeting of DM-associated complications.


Assuntos
Diabetes Mellitus/sangue , Membrana Eritrocítica/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Glucose/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Tiazóis/farmacologia , Animais , Apoptose/efeitos dos fármacos , Diabetes Mellitus/metabolismo , Relação Dose-Resposta a Droga , Glucose/administração & dosagem , Humanos , Peroxidação de Lipídeos , Camundongos , Estrutura Molecular , ATPase Trocadora de Sódio-Potássio/metabolismo , Tiazóis/administração & dosagem , Tiazóis/química
3.
J Biol Chem ; 289(46): 31879-31890, 2014 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-25231984

RESUMO

TNF is a pleotropic cytokine known to be involved in the progression of several pro-inflammatory disorders. Many therapeutic agents have been designed to counteract the effect of TNF in rheumatoid arthritis as well as a number of cancers. In the present study we have synthesized and evaluated the anti-cancer activity of novel biscoumarins in vitro and in vivo. Among new compounds, BIHC was found to be the most cytotoxic agent against the HepG2 cell line while exhibiting less toxicity toward normal hepatocytes. Furthermore, BIHC inhibited the proliferation of various hepatocellular carcinoma (HCC) cells in a dose- and time-dependent manner. Subsequently, using in silico target prediction, BIHC was predicted as a TNF blocker. Experimental validation was able to confirm this hypothesis, where BIHC could significantly inhibit the recombinant mouse TNF-α binding to its antibody with an IC50 of 16.5 µM. Furthermore, in silico docking suggested a binding mode of BIHC similar to a ligand known to disrupt the native, trimeric structure of TNF, and also validated with molecular dynamics simulations. Moreover, we have demonstrated the down-regulation of p65 phosphorylation and other NF-κB-regulated gene products upon BIHC treatment, and on the phenotypic level the compound shows inhibition of CXCL12-induced invasion of HepG2 cells. Also, we demonstrate that BIHC inhibits infiltration of macrophages to the peritoneal cavity and suppresses the activity of TNF-α in vivo in mice primed with thioglycollate broth and lipopolysaccharide. We comprehensively validated the TNF-α inhibitory efficacy of BIHC in an inflammatory bowel disease mice model.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Cumarínicos/química , Neoplasias Hepáticas/tratamento farmacológico , Fator de Necrose Tumoral alfa/química , Animais , Anti-Inflamatórios/química , Carcinoma Hepatocelular/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Desenho de Fármacos , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Humanos , Inflamação , Doenças Inflamatórias Intestinais/metabolismo , Concentração Inibidora 50 , Neoplasias Hepáticas/metabolismo , Espectroscopia de Ressonância Magnética , Camundongos , Simulação de Acoplamento Molecular , NF-kappa B/metabolismo , Ligação Proteica , Transdução de Sinais , Ressonância de Plasmônio de Superfície
4.
J Pineal Res ; 59(2): 240-54, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26103459

RESUMO

Oxidative stress-induced methemoglobinemia remained an untouched area in venom pharmacology till date. This study for the first time explored the potential of animal venoms to oxidize hemoglobin to methemoglobin. In in vitro whole-blood assay, methemoglobin forming ability of venoms varied as Naja naja > Ophiophagus hannah > Echis carinatus > Daboia russellii > Apis mellifera > Mesobuthus tamulus > Hippasa partita. Being highly potential, N. naja venom was further studied to observe methemoglobin formation in RBCs and in combinations with PMNs and PBMCs, where maximum effect was observed in RBCs + PMNs combination. Naja naja venom/externally added methemoglobin-induced methemoglobin formation was in parallel with ROS generation in whole blood/RBCs/RBCs + PMNs/RBCs + PBMCs. In in vivo studies, the lethal dose (1 mg/kg body weight, i.p.) of N. naja venom readily induced methemoglobin formation, ROS generation, expression of inflammatory markers, and hypoxia-inducible factor-3α. Although the mice administered with three effective doses of antivenom recorded zero mortality; the methemoglobin and ROS levels remained high. However, one effective dose of antivenom when administered along with melatonin (1:50; venom/melatonin, w/w), not only offered 100% survival of experimental mice, but also significantly reduced methemoglobin level, and oxidative stress markers including hypoxia-inducible factor-3α. This study provides strong drive that, complementing melatonin would not only reduce the antivenom load, but for sure greatly increase the success rate of antivenom therapy and drastically minimize the global incidence of snakebite deaths. However, further detailed investigations are needed before translating the combined therapy towards the bed side.


Assuntos
Melatonina/farmacologia , Metemoglobinemia/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Mordeduras de Serpentes/tratamento farmacológico , Animais , Humanos , Metemoglobinemia/sangue , Metemoglobinemia/etiologia , Camundongos , Mordeduras de Serpentes/sangue , Venenos de Serpentes/toxicidade
5.
Toxicol In Vitro ; 63: 104743, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31809793

RESUMO

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.


Assuntos
Plaquetas/efeitos dos fármacos , Diarileptanoides/toxicidade , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Plaquetas/metabolismo , Curcumina/toxicidade , Humanos
6.
Phytomedicine ; 64: 152924, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31465983

RESUMO

BACKGROUND: Arthritis is a common degenerative joint disease characterized by deterioration of articular cartilage, subchondral bone, and associated with immobility, pain and inflammation. The incessant action of reactive oxygen species (ROS) during progressive arthritis causes severe oxidative damage to vital organs and circulatory system. PURPOSE: In this study we investigated the ability of guggulipid (GL), a lipid rich extract from the gum resin of the plant Commiphora whighitii to suppress the progressive arthritis and associated liver oxidative stress both in vivo and in vitro. STUDY DESIGN/METHODS: The anti-arthritic ability of GL was demonstrated in vitro using IL-1ß stimulated bovine nasal cartilage model and in vivo Freund's complete adjuvant-induced arthritic rat model. Collagen/proteoglycan degradation and pro-inflammatory mediators were monitored in the harvested culture medium of nasal cartilage by estimating the levels of matrix metalloproteinases (MMPs), hydroxy proline, glycosaminoglycans and inflammatory mediators. Further, anti-arthritic ability of GL was evaluated in vivo by measuring enzymatic and non-enzymatic mediators of cartilage degradation, inflammation and oxidative stress markers. RESULTS: GL significantly inhibited the IL-1ß stimulated cartilage degradation in vitro by mitigating the MMPs activity, collagen degradation and secretion of pro-inflammatory mediators. Further, GL significantly reduced the adjuvant-induced paw swelling and body weight loss in vivo. GL remarkably reduced the MMPs and hyaluronidases activities in serum and bone homogenate along with altered hematological parameters. GL also mitigated the elevated bone resorbing enzymes cathepsins, exoglycosidases and phosphatases. Additionally, GL effectively mitigated ROS and oxidative stress-mediators recuperating the altered serum/liver oxidative stress and liver damage incurred during arthritic progression. CONCLUSION: In summary, the study clearly demonstrates the protective efficacy of GL against arthritis and its associated oxidative stress, particularly, liver oxidative damage. Hence, GL could be a potential alternative and complementary medicine to treat inflammatory joint diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Artrite Experimental/tratamento farmacológico , Commiphora/química , Inflamação/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Gomas Vegetais/farmacologia , Animais , Anti-Inflamatórios/administração & dosagem , Artrite Experimental/induzido quimicamente , Bovinos , Modelos Animais de Doenças , Adjuvante de Freund/efeitos adversos , Mediadores da Inflamação/metabolismo , Interleucina-1beta/metabolismo , Fígado/efeitos dos fármacos , Cartilagens Nasais/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Gomas Vegetais/administração & dosagem , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo
7.
Mini Rev Med Chem ; 18(3): 244-275, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28302039

RESUMO

Arthritis is marked by joint deterioration that affects articular cartilage and subchondral bone. Though cartilage degradation does the major damage during arthritis, subsequent bone degeneration cannot be neglected. Recent progress in arthritis research has identified the clinical importance of bone erosion in destructive arthritis. Studies have showed the key role played by osteoclasts and receptor activator of nuclear factor kappaB ligand (RANKL) signaling in bone erosion. Cathepsins and tartrate resistant acid phosphatase (TRAP) are considered key enzymatic factors contributing to bone erosion. Further, reactive oxygen species (ROS) formed at the ruffled border of osteoclasts also causes bone resorption and matrix degradation. Besides, severe inflammation during arthritis induces bone erosion by aiding in Ca2+ removal and activating osteoclastogenesis. The inflammatory cytokines and ROS influence osteoclast differentiation by regulating osteoclast-lineage cells or by acting on other cells to regulate the expression of RANKL and osteoprotegerin (OPG). The enhanced production of pro-inflammatory cytokines and ROS in arthritis stimulates tissue injury by means of oxidative damage leading to vital organ damage and synovial and circulatory cell apoptosis. Thus, blocking enzymatic and non-enzymatic factors responsible for bone erosion and inflammation is considered a prime strategy in the management of arthritis. In this review we provide an overview of the mechanisms of bone erosion, inflammation and associated oxidative stress/damage during arthritis perpetuation along with shedding light on potential targets. The article also describes the possible natural therapeutic agents that could prevent bone loss and inflammation, and related secondary complications of arthritis.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Produtos Biológicos/uso terapêutico , Reabsorção Óssea/tratamento farmacológico , Inflamação/tratamento farmacológico , Animais , Artrite Reumatoide/complicações , Produtos Biológicos/química , Humanos
8.
Acta Trop ; 169: 14-25, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28089603

RESUMO

Snakebite is a neglected health hazard. Its patho-physiology has largely been focused on systemic and local toxicities; whereas, venom and antivenom induced oxidative stress has long been ignored. Antivenom therapy although neutralizes venom lethality and saves many lives, remains ineffective against oxidative stress. This prompted us to complement antivenom with an antioxidant molecule melatonin that would protect against oxidative stress and increase the efficacy of the existing snakebite therapy. Here we show that D. russelli and E. carinatus venoms induce strong oxidative stress that persists even after antivenom administration in mice model. Additionally, antivenoms also induce oxidative stress. Polyvalent antivenom induce more oxidative stress than monovalent antivenom. Strikingly, antivenom and melatonin together not only inhibit venom and antivenom induced oxidative stress but also significantly reduce the neutralizing antivenom dose. This study provides a therapeutic potential for enhancing the existing snakebite therapy. The combined treatment of antivenom+melatonin would prevent the upsurge of oxidative stress as well as minimize the antivenom load. Thus the investigation offers immense scope for physicians and toxinologists to reinvestigate, design new strategies and think beyond the conventional mode of antivenom therapy.


Assuntos
Antivenenos/farmacologia , Melatonina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Mordeduras de Serpentes/patologia , Venenos de Víboras/toxicidade , Animais , Modelos Animais de Doenças , Feminino , Camundongos , Coelhos , Resultado do Tratamento
10.
Nat Commun ; 7: 11361, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-27093631

RESUMO

Indian Echis carinatus bite causes sustained tissue destruction at the bite site. Neutrophils, the major leukocytes in the early defence process, accumulate at the bite site. Here we show that E. carinatus venom induces neutrophil extracellular trap (NET) formation. The NETs block the blood vessels and entrap the venom toxins at the injection site, promoting tissue destruction. The stability of NETs is attributed to the lack of NETs-degrading DNase activity in E. carinatus venom. In a mouse tail model, mice co-injected with venom and DNase 1, and neutropenic mice injected with the venom, do not develop NETs, venom accumulation and tissue destruction at the injected site. Strikingly, venom-induced mice tail tissue destruction is also prevented by the subsequent injection of DNase 1. Thus, our study suggests that DNase 1 treatment may have a therapeutic potential for preventing the tissue destruction caused by snake venom.


Assuntos
Antídotos/farmacologia , Desoxirribonuclease I/farmacologia , Armadilhas Extracelulares/efeitos dos fármacos , Necrose/prevenção & controle , Neutropenia/imunologia , Venenos de Víboras/antagonistas & inibidores , Animais , Antídotos/metabolismo , Desoxirribonuclease I/metabolismo , Armadilhas Extracelulares/imunologia , Feminino , Injeções Intralesionais , Masculino , Camundongos , Necrose/induzido quimicamente , Necrose/patologia , Neutrófilos/citologia , Neutrófilos/imunologia , Fatores de Proteção , Cauda/efeitos dos fármacos , Cauda/imunologia , Cauda/patologia , Venenos de Víboras/administração & dosagem , Venenos de Víboras/toxicidade , Viperidae/fisiologia
11.
PLoS One ; 11(9): e0163209, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27685808

RESUMO

Aberrant activation of nuclear factor kappa B (NF-κB) has been linked with the pathogenesis of several proinflammatory diseases including number of cancers and inflammatory bowel diseases. In the present work, we evaluated the anticancer activity of 1,2-oxazines derivatives against colorectal cancer cell lines and identified 2-((2-acetyl-6,6-dimethyl-4-phenyl-5,6-dihydro-2H-1,2-oxazin-3-yl)methyl)isoindoline-1,3-dione (API) as the lead anticancer agent among the tested compounds. The apoptosis inducing effect of API was demonstrated using flow cytometry analysis and measuring the caspase 3/7 activity in API treated cells. Based on the literature on inhibition of NF-κB by oxazines, we evaluated the effect of 1,2-oxazines against the ability of NF-κB binding to DNA, NF-κB-dependent luciferase expression and IκBα phosphorylation. We found that, API abrogate constitutive activation of NF-κB and inhibits IκBα phosphorylation in HCT116 cells. Our in silico analysis revealed the binding of oxazines to the hydrophobic cavity that present between the interface of p65 and IκBα. Given the relevance with aberrant activation of NF-κB in inflammation bowel disease (IBD), we evaluated the effect of API on dextran sulphate sodium-induced IBD mice model. The treatment of IBD induced mice with API decreased the myeloperoxidase activity in colonic extract, modulated the colon length and serum levels of pro- and anti-inflammatory cytokines such as TNF-α, IFN-γ, IL-6, IL-1ß and IL-10. Furthermore, the histological analysis revealed the restoration of the distorted cryptic epithelial structure of colon in the API treated animals. In conclusion, we comprehensively validated the NF-κB inhibitory efficacy of API that targets NF-κB in in vitro colon cancer and an in vivo inflammatory bowel disease model.

12.
PLoS One ; 10(7): e0131896, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26196520

RESUMO

Drugs such as necopidem, saripidem, alpidem, zolpidem, and olprinone contain nitrogen-containing bicyclic, condensed-imidazo[1,2-α]pyridines as bioactive scaffolds. In this work, we report a high-yield one pot synthesis of 1-(2-methyl-8-aryl-substitued-imidazo[1,2-α]pyridin-3-yl)ethan-1-onefor the first-time. Subsequently, we performed in silico mode-of-action analysis and predicted that the synthesized imidazopyridines targets Phospholipase A2 (PLA2). In vitro analysis confirmed the predicted target PLA2 for the novel imidazopyridine derivative1-(2-Methyl-8-naphthalen-1-yl-imidazo [1,2-α]pyridine-3-yl)-ethanone (compound 3f) showing significant inhibitory activity towards snake venom PLA2 with an IC50 value of 14.3 µM. Evidently, the molecular docking analysis suggested that imidazopyridine compound was able to bind to the active site of the PLA2 with strong affinity, whose affinity values are comparable to nimesulide. Furthermore, we estimated the potential for oral bioavailability by Lipinski's Rule of Five. Hence, it is concluded that the compound 3f could be a lead molecule against snake venom PLA2.


Assuntos
Daboia , Fosfolipases A2 do Grupo II/antagonistas & inibidores , Fosfolipases A2 do Grupo II/química , Simulação de Acoplamento Molecular , Inibidores de Fosfolipase A2 , Piridinas , Animais , Inibidores de Fosfolipase A2/síntese química , Inibidores de Fosfolipase A2/química , Piridinas/síntese química , Piridinas/química , Venenos de Víboras
13.
Sci Rep ; 5: 15045, 2015 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-26459859

RESUMO

Thrombocytopenia is one of the most frequently observed secondary complications in many pathological conditions including liver diseases, where hyperbilirubinemia is very common. The present study sought to find the cause of thrombocytopenia in unconjugated hyperbilirubinemic conditions. Unconjugated bilirubin (UCB), an end-product of heme catabolism, is known to have pro-oxidative and cytotoxic effects at high serum concentration. We investigated the molecular mechanism underlying the pro-apoptotic effect of UCB on human platelets in vitro, and followed it up with studies in phenylhydrazine-induced hyperbilirubinemic rat model and hyperbilirubinemic human subjects. UCB is indeed found to significantly induce platelet apoptotic events including elevated endogenous reactive oxygen species generation, mitochondrial membrane depolarization, increased intracellular calcium levels, cardiolipin peroxidation and phosphatidylserine externalization (p < 0.001) as evident by FACS analysis. The immunoblots show the elevated levels of cytosolic cytochrome c and caspase activation in UCB-treated platelets. Further, UCB is found to induce mitochondrial ROS generation leading to p38 activation, followed by downstream activation of p53, ultimately resulting in altered expression of Bcl-2 and Bax proteins as evident from immunoblotting. All these parameters conclude that elevated unconjugated bilirubin causes thrombocytopenia by stimulating platelet apoptosis via mitochondrial ROS-induced p38 and p53 activation.


Assuntos
Apoptose , Bilirrubina/metabolismo , Plaquetas/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Apoptose/efeitos dos fármacos , Bilirrubina/farmacologia , Plaquetas/efeitos dos fármacos , Cálcio/metabolismo , Cardiolipinas/metabolismo , Modelos Animais de Doenças , Humanos , Hiperbilirrubinemia/metabolismo , Potencial da Membrana Mitocondrial , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosforilação , Ratos , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo
14.
Sci Rep ; 5: 11117, 2015 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-26059174

RESUMO

Medicinal plants are employed in the treatment of human ailments from time immemorial. Several studies have validated the use of medicinal plant products in arthritis treatment. Arthritis is a joint disorder affecting subchondral bone and cartilage. Degradation of cartilage is principally mediated by enzymes like matrix metalloproteinases (MMPs), hyaluronidases (HAase), aggrecanases and exoglycosidases. These enzymes act upon collagen, hyaluronan and aggrecan of cartilage respectively, which would in turn activate bone deteriorating enzymes like cathepsins and tartrate resistant acid phosphatases (TRAP). Besides, the incessant action of reactive oxygen species and the inflammatory mediators is reported to cause further damage by immunological activation. The present study demonstrated the anti-arthritic efficacy of tamarind seed extract (TSE). TSE exhibited cartilage and bone protecting nature by inhibiting the elevated activities of MMPs, HAase, exoglycosidases, cathepsins and TRAP. It also mitigated the augmented levels of inflammatory mediators like interleukin (IL)-1ß, tumor necrosis factor-α, IL-6, IL-23 and cyclooxygenase-2. Further, TSE administration alleviated increased levels of ROS and hydroperoxides and sustained the endogenous antioxidant homeostasis by balancing altered levels of endogenous antioxidant markers. Overall, TSE was observed as a potent agent abrogating arthritis-mediated cartilage/bone degradation, inflammation and associated stress in vivo demanding further attention.


Assuntos
Artrite Experimental/tratamento farmacológico , Osso e Ossos/efeitos dos fármacos , Cartilagem/efeitos dos fármacos , Inflamação/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Sementes/química , Tamarindus/embriologia , Animais , Osso e Ossos/patologia , Cartilagem/patologia , Mediadores da Inflamação/metabolismo , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar
15.
PLoS One ; 10(6): e0127558, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26083398

RESUMO

Thrombocytopenia in methotrexate (MTX)-treated cancer and rheumatoid arthritis (RA) patients connotes the interference of MTX with platelets. Hence, it seemed appealing to appraise the effect of MTX on platelets. Thereby, the mechanism of action of MTX on platelets was dissected. MTX (10 µM) induced activation of pro-apoptotic proteins Bid, Bax and Bad through JNK phosphorylation leading to ΔΨm dissipation, cytochrome c release and caspase activation, culminating in apoptosis. The use of specific inhibitor for JNK abrogates the MTX-induced activation of pro-apoptotic proteins and downstream events confirming JNK phosphorylation by MTX as a key event. We also demonstrate that platelet mitochondria as prime sources of ROS which plays a central role in MTX-induced apoptosis. Further, MTX induces oxidative stress by altering the levels of ROS and glutathione cycle. In parallel, the clinically approved thiol antioxidant N-acetylcysteine (NAC) and its derivative N-acetylcysteine amide (NACA) proficiently alleviate MTX-induced platelet apoptosis and oxidative damage. These findings underpin the dearth of research on interference of therapeutic drugs with platelets, despite their importance in human health and disease. Therefore, the use of antioxidants as supplementary therapy seems to be a safe bet in pathologies associated with altered platelet functions.


Assuntos
Acetilcisteína/análogos & derivados , Acetilcisteína/farmacologia , Antimetabólitos Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , MAP Quinase Quinase 4/genética , Metotrexato/farmacologia , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/genética , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Plaquetas/citologia , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Regulação da Expressão Gênica , Humanos , MAP Quinase Quinase 4/metabolismo , Potencial da Membrana Mitocondrial , Metotrexato/antagonistas & inibidores , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Oxirredução , Estresse Oxidativo , Fosforilação , Cultura Primária de Células , Transdução de Sinais , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo , Proteína de Morte Celular Associada a bcl/genética , Proteína de Morte Celular Associada a bcl/metabolismo
16.
PLoS One ; 9(9): e106364, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25184206

RESUMO

The classical antivenom therapy has appreciably reduced snakebite mortality rate and thus is the only savior drug available. Unfortunately, it considerably fails to shield the viper bite complications like hemorrhage, local tissue degradation and necrosis responsible for severe morbidity. Moreover, the therapy is also tagged with limitations including anaphylaxis, serum sickness and poor availability. Over the last decade, snake venom metalloproteases (SVMPs) are reported to be the primary component responsible for hemorrhage and tissue degradation at bitten site. Thus, antivenom inability to offset viper venom-induced local toxicity has been a basis for an insistent search for SVMP inhibitors. Here we report the inhibitory effect of compound 5d, an apigenin based molecule against SVMPs both in silico and in vivo. Several apigenin analogues are synthesized using multicomponent Ugi reactions. Among them, compound 5d effectively abrogated Echis carinatus (EC) venom-induced local hemorrhage, tissue necrosis and myotoxicity in a dose dependant fashion. The histopathological study further conferred effective inhibition of basement membrane degradation, and accumulation of inflammatory leucocytes at the site of EC venom inoculation. The compound also protected EC venom-induced fibrin and fibrinogen degradation. The molecular docking of compound 5d and bothropasin demonstrated the direct interaction of hydroxyl group of compound with Glu146 present in hydrophobic pocket of active site and does not chelate Zn2+. Hence, it is concluded that compound 5d could be a potent agent in viper bite management.


Assuntos
Apigenina/administração & dosagem , Hemorragia/tratamento farmacológico , Metaloproteases/antagonistas & inibidores , Mordeduras de Serpentes/tratamento farmacológico , Animais , Apigenina/síntese química , Apigenina/química , Venenos de Crotalídeos/química , Fibrina/química , Fibrina/metabolismo , Fibrinogênio/química , Fibrinogênio/metabolismo , Hemorragia/patologia , Metaloendopeptidases/química , Metaloproteases/metabolismo , Camundongos , Simulação de Acoplamento Molecular , Mordeduras de Serpentes/patologia , Venenos de Serpentes/antagonistas & inibidores , Venenos de Serpentes/química , Venenos de Serpentes/enzimologia , Viperidae
17.
PLoS One ; 9(7): e102759, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25047583

RESUMO

Glycoside hydrolases catalyze the selective hydrolysis of glycosidic bonds in oligosaccharides, polysaccharides, and their conjugates. ß-glucosidases occur in all domains of living organisms and constitute a major group among glycoside hydrolases. On the other hand, the benzoxazinoids occur in living systems and act as stable ß-glucosides, such as 2-(2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one)-ß-D-gluco-pyranose, which hydrolyse to an aglycone DIMBOA. Here, we synthesized the library of novel 1,3-benzoxazine scaffold based aglycones by using 2-aminobenzyl alcohols and aldehydes from one-pot reaction in a chloroacetic acid catalytic system via aerobic oxidative synthesis. Among the synthesized benzoxazines, 4-(7-chloro-2,4-dihydro-1H-benzo[d][1,3]oxazin-2-yl)phenol (compound 7) exhibit significant inhibition towards glucosidase compared to acarbose, with a IC50 value of 11.5 µM. Based upon results generated by in silico target prediction algorithms (Naïve Bayesian classifier), these aglycones potentially target the additional sodium/glucose cotransporter 1 (where a log likelihood score of 2.70 was observed). Furthermore, the in vitro glucosidase activity was correlated with the in silico docking results, with a high docking score for the aglycones towards the substrate binding site of glycosidase. Evidently, the in vitro and in vivo experiments clearly suggest an anti-hyperglycemic effect via glucose uptake inhibition by 4-(7-chloro-2,4-dihydro-1H-benzo[d][1,3]oxazin-2-yl)phenol in the starved rat model. These synthetic aglycones could constitute a novel pharmacological approach for the treatment, or re-enforcement of existing treatments, of type 2 diabetes and associated secondary complications.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Glucose/metabolismo , Glicosídeo Hidrolases/metabolismo , Animais , Teorema de Bayes , Sítios de Ligação , Ratos , Especificidade por Substrato
18.
PLoS One ; 9(9): e107182, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25238069

RESUMO

Thrombocytopenia is a serious issue connected with the pathogenesis of several human diseases including chronic inflammation, arthritis, Alzheimer's disease, cardiovascular diseases (CVDs) and other oxidative stress-associated pathologies. The indiscriminate use of antibiotics and other biological drugs are reported to result in thrombocytopenia, which is often neglected during the treatment regime. In addition, augmented oxidative stress induced by drugs and pathological conditions has also been shown to induce thrombocytopenia, which seems to be the most obvious consequence of elevated rate of platelet apoptosis. Thus, blocking oxidative stress-induced platelet apoptosis would be of prime importance in order to negotiate thrombocytopenia and associated human pathologies. The current study presents the synthesis and platelet protective nature of novel ibuprofen derivatives. The potent anti-oxidant ibuprofen derivative 4f was selected for the study and the platelet protective efficacy and platelet aggregation inhibitory property has been demonstrated. The compound 4f dose dependently mitigates the oxidative stress-induced platelet apoptosis in both platelet rich plasma and washed platelets. The platelet protective nature of compound 4f was determined by assessing various apoptotic markers such as ROS generation, cytosolic Ca2+ levels, PS externalization, cytochrome C translocation, Caspase activation, mitochondrial membrane depolarization, cytotoxicity, LDH leakage and tyrosine phosphorylation of cytosolic proteins. Furthermore, compound 4f dose dependently ameliorated agonist induced platelet aggregation. Therefore, compound 4f can be estimated as a potential candidate in the treatment regime of pathological disorders associated with platelet activation and apoptosis. In addition, compound 4f can be used as an auxiliary therapeutic agent in pathologies associated with thrombocytopenia.


Assuntos
Apoptose/efeitos dos fármacos , Plaquetas/efeitos dos fármacos , Ibuprofeno/análogos & derivados , Agregação Plaquetária/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Plaquetas/citologia , Plaquetas/metabolismo , Relação Dose-Resposta a Droga , Humanos , Ibuprofeno/química , Ibuprofeno/farmacologia , Estresse Oxidativo/efeitos dos fármacos
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