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1.
J Acoust Soc Am ; 146(2): 1164, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31472592

RESUMO

Assessment of intelligibility is required to characterize the overall speech production capability and to measure the speech outcome of different interventions for individuals with cleft lip and palate (CLP). Researchers have found that articulation error and hypernasality have a significant effect on the degradation of CLP speech intelligibility. Motivated by this finding, the present work proposes an objective measure of sentence-level intelligibility by combining the information of articulation deficits and hypernasality. These two speech disorders represent different aspects of CLP speech. Hence, it is expected that the composite measure based on them may utilize complementary clinical information. The objective scores of articulation and hypernasality are used as features to train a regression model, and the output of the model is considered as the predicted intelligibility score. The Spearman's correlation coefficient based analysis shows a significant correlation between the predicted and perceptual intelligibility scores (ρ = 0.77, p < 0.001).


Assuntos
Fenda Labial/fisiopatologia , Fissura Palatina/fisiopatologia , Cavidade Nasal/fisiologia , Inteligibilidade da Fala , Voz/fisiologia , Criança , Fenda Labial/complicações , Fissura Palatina/complicações , Feminino , Humanos , Masculino , Acústica da Fala
2.
Front Microbiol ; 8: 2317, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29213265

RESUMO

Fumonisin B1 (FB1), a mycotoxin produced by Fusarium species is a predominant Group 2B carcinogen occurring in maize and maize-based poultry feeds. It is shown to be nephrotoxic, hepatotoxic, neurotoxic, and immunosuppressing in animals. In this study, we report the ameliorating effects of a probiotic strain, Lactobacillus plantarum MYS6 on FB1-induced toxicity and oxidative damage in broilers. A 6-week dietary experiment consisting of 48 broilers was performed in six treatment groups. Probiotic treatment (109 cells/mL) involved pre-colonization of broilers with L. plantarum MYS6 while co-administration treatment involved supplementation of probiotic and FB1-contaminated diet (200 mg/Kg feed) simultaneously. At the end of the treatment period, growth performance, hematology, serum biochemistry, and markers of oxidative stress in serum and tissue homogenates were evaluated in all the broilers. The histopathological changes in hepatic and renal tissues were further studied. The results demonstrated that administration of L. plantarum MYS6 efficiently improved the feed intake, body weight and feed conversion ratio in broilers. It mitigated the altered levels of hematological indices such as complete blood count, hemoglobin, and hematocrit. Serum parameters such as serum glutamic oxaloacetic transaminase, serum glutamic pyruvic transaminase, creatinine, cholesterol, triglycerides, and albumin were significantly restored after administering the probiotic in FB1-intoxicated broilers. Additionally, L. plantarum MYS6 alleviated the levels of oxidative stress markers in serum and tissue homogenate of liver. The histopathological data of liver and kidney further substantiated the overall protection offered by L. plantarum MYS6 against FB1-induced cellular toxicity and organ damage in broilers. Our results indicated that co-administration of probiotic along with the toxin had better effect in detoxification compared to its pre-colonization in broilers. Collectively, our study signifies the protective role of L. plantarum MYS6 in ameliorating the FB1-induced toxicity in the vital organs and subsequent oxidative stress in broilers. The probiotic L. plantarum MYS6 can further be formulated into a functional feed owing to its anti-fumonisin attributes and role in mitigating FB1-induced hepatorenal damage.

3.
Appl Biochem Biotechnol ; 182(4): 1415-1432, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28155167

RESUMO

Bioactive peptide research has experienced considerable therapeutic interest owing to varied physiological functions, efficacy in excretion, and tolerability of peptides. Colostrum is a rich natural source of bioactive peptides with many properties elucidated such as anti-thrombotic, anti-hypertensive, opioid, immunomodulatory, etc. In this study, a variant peptide derived from ß-lactoglobulin from buffalo colostrum was evaluated for the anti-ophidian property by targeting snake venom metalloproteinases. These are responsible for rapid local tissue damages that develop after snakebite such as edema, hemorrhage, myonecrosis, and extracellular matrix degradation. The peptide identified by LC-MS/MS effectively neutralized hemorrhagic activity of the Echis carinatus venom in a dose-dependent manner. Histological examinations revealed that the peptide mitigated basement membrane degradation and accumulation of inflammatory leucocytes at the venom-injected site. Inhibition of proteolytic activity was evidenced in both casein and gelatin zymograms. Also, inhibition of fibrinolytic and fibrinogenolytic activities was seen. The UV-visible spectral study implicated Zn2+ chelation, which was further confirmed by molecular docking and dynamic studies by assessing molecular interactions, thus implicating the probable mechanism for inhibition of venom-induced proteolytic and hemorrhagic activities. The present investigation establishes newer vista for the BLG-col peptide with anti-ophidian efficacy as a promising candidate for therapeutic interventions.


Assuntos
Búfalos , Colostro/química , Lactoglobulinas/química , Metaloproteases/antagonistas & inibidores , Fragmentos de Peptídeos/farmacologia , Venenos de Víboras/enzimologia , Viperidae , Sequência de Aminoácidos , Animais , Caseínas/metabolismo , Simulação por Computador , Edema/tratamento farmacológico , Fibrina/metabolismo , Fibrinogênio/metabolismo , Hemorragia/induzido quimicamente , Hemorragia/tratamento farmacológico , Hidrólise , Metaloproteases/química , Metaloproteases/metabolismo , Camundongos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Oligopeptídeos/química , Oligopeptídeos/metabolismo , Oligopeptídeos/farmacologia , Oligopeptídeos/uso terapêutico , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/uso terapêutico , Inibidores de Proteases/química , Inibidores de Proteases/metabolismo , Inibidores de Proteases/farmacologia , Inibidores de Proteases/uso terapêutico , Conformação Proteica , Proteólise/efeitos dos fármacos , Pele/efeitos dos fármacos
4.
J Biomol Struct Dyn ; 35(9): 1979-1989, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27334983

RESUMO

Viper venom hyaluronidase (VV-HYA) inhibitors have long been used as therapeutic agents for arresting the local and systemic effects caused during its envenomation. Henceforth, to understand its structural features and also to identify the best potential inhibitor against it the present computational study was undertaken. Structure-based homology modeling of VV-HYA followed by its docking and free energy-based ranking analysis of ligand, the MD simulations of the lead complex was also performed. The sequence analysis and homology modeling of VV-HYA revealed a distorted (ß/α)8 folding as in the case of hydrolases family of proteins. Molecular docking of the resultant 3D structure of VV-HYA with known inhibitors (compounds 1-25) revealed the importance of molecular recognition of hotspot residues (Tyr 75, Arg 288, and Trp 321) other than that of the active site residues. It also revealed that Trp 321 of VV-HYA is highly important for mediating π-π interactions with ligands. In addition, the molecular docking and comparative free energy binding analysis was investigated for the VV-HYA inhibitors (compounds 1-25). Both molecular docking and relative free energy binding analysis clearly confirmed the identification of sodium chromoglycate (compound 1) as the best potential inhibitor against VV-HYA. Molecular dynamics simulations additionally confirmed the stability of their binding interactions. Further, the information obtained from this work is believed to serve as an impetus for future rational designing of new novel VV-HYA inhibitors with improved activity and selectivity.


Assuntos
Inibidores Enzimáticos/química , Hialuronoglucosaminidase/química , Mordeduras de Serpentes/tratamento farmacológico , Venenos de Víboras/enzimologia , Biologia Computacional , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Humanos , Hialuronoglucosaminidase/antagonistas & inibidores , Modelos Moleculares , Simulação de Acoplamento Molecular , Ligação Proteica , Mordeduras de Serpentes/enzimologia , Venenos de Víboras/química , Venenos de Víboras/toxicidade
5.
Cytotechnology ; 68(1): 73-85, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25149285

RESUMO

Viper envenomation results in inflammation at the bitten site as well as target organs. Neutrophils and other polymorphonuclear leukocytes execute inflammation resolving mechanism and will undergo apoptosis after completing the task. However, the target specific toxins induce neutrophil apoptosis at the bitten site and in circulation prior to their function, thus reducing their number. Circulating activated neutrophils are major source of inflammatory cytokines and leakage of reactive oxygen species (ROS)/other toxic intermediates resulting in aggravation of inflammatory response at the bitten/target site. Therefore, neutralization of venom induced neutrophil apoptosis reduces inflammation besides increasing the functional neutrophil population. Therefore, the present study investigates the venom induced perturbances in isolated human neutrophils and its neutralization by crocin (Crocus sativus) a potent antioxidant carotenoid. Human neutrophils on treatment with venom resulted in altered ROS generation, intracellular Ca(2+) mobilization, mitochondrial membrane depolarization, cyt-c translocation, caspase activation, phosphatidylserine externalization and DNA damage. On the other hand significant protection against oxidative stress and apoptosis were evidenced in crocin pre-treated groups. In conclusion the viper venom induces neutrophil apoptosis and results in aggravation of inflammation and tissue damage. The present study demands the necessity of an auxiliary therapy in addition to antivenin therapy to treat secondary/overlooked complications of envenomation.

6.
Biochim Biophys Acta ; 1850(12): 2393-409, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26391844

RESUMO

BACKGROUND: Echis carinatus bite is a serious threat in South-Asian countries including India, as it causes highest number of deaths and terrifying long-term tissue destruction at the bitten site. Although venom metalloproteinases and hyaluronidases are the suggested key players, studies on the effect of venom on polymorphonuclear cells, peripheral blood mononuclear cells and platelets, and their role in long-term tissue destruction are still in infancy. While, the effect of venom on collagen receptors, integrin α2ß1/GP VI/DDR1 and CX3CR1 chemokine receptor present on these cells is an untouched area. METHODS: Lupeol, lupeol acetate, its synthetic derivatives 2-8 were screened for inhibition of E. carinatus venom induced-hemorrhage in mouse model where compound 8 was found to be the most potent. Further, compound 8 efficiently neutralized venom induced hemorrhage, edema, dermonecrosis, myonecrosis, myotoxicity, pro-coagulant, oxidative stress, inflammatory cytokines and cleavage of collagen and CX3CR1 receptors on inflammatory cells in in vivo, in silico, ex vivo and in vitro studies. CONCLUSIONS: This study for the first time demonstrated the cleavage of collagen receptors and the receptor for angiogenesis and wound healing by the venom and its inhibition by compound 8, as these are important for firm adhesion of inflammatory cells at the damaged site to resolve inflammation and promote tissue repair. GENERAL SIGNIFICANCE: This study provides a lead in venom pharmacology, wherein, compound 8 could be a therapeutic agent for the better management of viper venom-induced long-term tissue destruction.


Assuntos
Antivenenos/farmacologia , Colágeno/metabolismo , Neovascularização Patológica , Triterpenos Pentacíclicos/farmacologia , Receptores de Superfície Celular/efeitos dos fármacos , Venenos de Víboras/toxicidade , Animais , Humanos , Masculino
7.
J Contemp Dent Pract ; 16(2): 130-4, 2015 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-25906804

RESUMO

BACKGROUND: Prompt-L-Pop is a sixth generation bonding system contains methacrylated phosphoric acid esters that combine an acidic component for etching the enamel and a primer, is an all-in-one adhesive. This study was undertaken to compare the bonding strength of brackets to enamel with traditional bonding technique and the new Prompt-L-Pop system using the same composite resin. MATERIALS AND METHODS: In this in vitro experimental study, 60 human premolar teeth extracted for orthodontic treatment were collected. The samples were randomly divided into three groups comprising of 20 teeth in each group. Shear bond strength and ARI scores for the specimens were measured. Comparison was done using one way ANOVA and Chi-square test. RESULTS: Fourth generation bonding adhesive system depicted similar bond strength to fifth generation bonding adhesive system. Both fourth and fifth generation exhibited higher shear bond strength as compared to sixth generation bonding adhesive system. CONCLUSION: Fourth and fifth generation exhibited higher shear bond strength as compared to sixth generation bonding adhesive system but the sixth generation has clinically acceptable shear bond strength. Also, it was found that sixth generation leaves less residual adhesive on the tooth after bracket removal.


Assuntos
Colagem Dentária/métodos , Braquetes Ortodônticos , Cimentos de Resina/química , Condicionamento Ácido do Dente/métodos , Adesividade , Bis-Fenol A-Glicidil Metacrilato/química , Esmalte Dentário/ultraestrutura , Análise do Estresse Dentário/instrumentação , Humanos , Cura Luminosa de Adesivos Dentários/métodos , Teste de Materiais , Ácidos Polimetacrílicos/química , Distribuição Aleatória , Resistência ao Cisalhamento , Estresse Mecânico , Propriedades de Superfície
8.
Toxicon ; 98: 89-97, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25727382

RESUMO

Though systemic and local manifestations of snakebite are considered serious, the relevance of oxidative stress in viper bite pathology is largely denied. However, over the past decade, studies have provided substantial evidence for the presence of persistent oxidative stress in viper bite victims. This review aims at highlighting the disturbances in redox homeostasis soon after viper envenomation and its implications in the pathomechanism of secondary/long term complications including thrombocytopenia, hypopituitarism, infertility, renal abnormalities and persistent local tissue degradation. Both enzymatic and non-enzymatic components of viper venom play a pivotal role in bringing redox turbulence in victims. Venom-induced hemorrhage and necrosis with subsequent release of damage associated molecular pattern (DAMPs) molecules also contribute to sustained oxidative stress and inflammation. Studies have demonstrated that along with anti-venom therapy an antioxidant treatment during the early stages of viper bite and also long term treatment could help to reduce the occurrence of secondary/long term complications. Further, proper knowledge regarding the pathophysiology will allow for exploration of new avenues in the treatment of viper bite.


Assuntos
Inflamação/patologia , Estresse Oxidativo/efeitos dos fármacos , Mordeduras de Serpentes/patologia , Venenos de Víboras/toxicidade , Animais , Antioxidantes/uso terapêutico , Antivenenos/uso terapêutico , Modelos Animais de Doenças , Hemorragia/etiologia , Hemorragia/patologia , Hemorragia/prevenção & controle , Homeostase , Humanos , Hipopituitarismo/etiologia , Hipopituitarismo/patologia , Hipopituitarismo/prevenção & controle , Inflamação/tratamento farmacológico , Inflamação/etiologia , Rim/anormalidades , Rim/patologia , Necrose/etiologia , Necrose/patologia , Necrose/prevenção & controle , Mordeduras de Serpentes/complicações , Mordeduras de Serpentes/tratamento farmacológico , Trombocitopenia/etiologia , Trombocitopenia/patologia , Trombocitopenia/prevenção & controle , Anormalidades Urogenitais/etiologia , Anormalidades Urogenitais/patologia , Anormalidades Urogenitais/prevenção & controle
9.
J Contemp Dent Pract ; 16(12): 963-70, 2015 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27018031

RESUMO

BACKGROUND AND OBJECTIVES: The purpose of this in vitro study was to evaluate the bond strength of the laser-etched base bracket, site of bond failure, and evaluate for enamel remnants on the bracket base after debonding, when compared to foil mesh base bracket. MATERIALS AND METHODS: Sixty noncarious, human premolar extracted for the orthodontic treatment were used for this study. The teeth were randomly divided into two groups containing 30 teeth each, which were bonded with laser-etched base bracket and mesh base bracket using light cure resin. The tensile and mechanical bond strength was tested after 24 hours using TIRA. The forces recorded during debonding were measured in Newton and final readings were tabulated in megapascals (MPa). After debonding, the amount of residual adhesive and enamel detachment on the bracket base were assessed according to adhesive remnant index (ARI) and enamel detachment index (EDI) using stereomicroscope and energy dispersive X-ray spectrometer. RESULTS: The laser-etched base bracket showed statistically significant higher results than mesh base bracket. Mann-Whitney test indicated that laser-etched base bracket had significantly higher tensile bond strength of 8.47 MPa (SD ± 0.84), fatigue strength of 7.75 MPa (SD ± 0.79) compared to mesh base bracket with tensile bond strength of 5.53 Mpa (SD ± 0.89) and fatigue strength of 5.17 MPa (SD ± 1.15). Adhesive remnant index score indicated that laser-etched base bracket had ARI score of 3 for most of the bracket, when compared to mesh base bracket. This was statistically significant. Enamel detachment index scores indicated that less than 10% of enamel detachment occurred in both the types of brackets, which was not statistically significant. CONCLUSION: Laser-etched base bracket showed superior bond strength, when compared to the foil mesh base bracket. The site of bond failure of these laser-etched base bracket was at the interface of enamel-adhesive and did not induce any significant enamel detachment. Thus, we can conclude that laser-etched base bracket is a promising step toward achieving an ideal bracket base design for successful bonding.


Assuntos
Descolagem Dentária , Análise do Estresse Dentário , Cura Luminosa de Adesivos Dentários , Braquetes Ortodônticos , Resinas Compostas , Colagem Dentária , Esmalte Dentário , Humanos , Teste de Materiais , Cimentos de Resina , Propriedades de Superfície
10.
Crit Rev Oncol Hematol ; 93(3): 149-58, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25439323

RESUMO

Platelets, once considered mediators of hemostasis and thrombosis, are now known to be involved in wound healing, inflammation, cardiovascular diseases, diabetes, arthritis, and cancer. Recent reports attest that platelets possess the cellular machinery to undergo apoptosis and that platelet apoptosis can be triggered by myriad stimuli including chemical and physical agonists, and pathophysiological conditions. Augmented rate of platelet apoptosis leads to thrombocytopenia, bleeding disorders and microparticle generation. Despite knowing the significant role of platelets in health and disease, and that any alterations in platelet functions can wreak havoc to the health, the offshoot reactions of therapeutic drugs on platelets and the far-reaching consequences are often neglected. The present review focuses on the impact of platelet apoptosis and the role of platelet-derived microparticles on different pathophysiological conditions. It also touches upon the effects of biologicals on platelets, and discusses the need to overcome the adverse effects of pro-apoptotic drugs through auxiliary therapy.


Assuntos
Apoptose , Plaquetas/fisiologia , Apoptose/efeitos dos fármacos , Transtornos Plaquetários/etiologia , Plaquetas/efeitos dos fármacos , Micropartículas Derivadas de Células , Humanos
11.
Int Immunopharmacol ; 21(1): 148-55, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24815989

RESUMO

The venom of the largest venomous snake, the king cobra (Ophiophagus hannah), is still out of league for the production of therapeutic polyvalent antivenom nor it is characterized immunologically in the Indian subcontinent. In the present study, the king cobra venom is comparatively studied for the cross-reactivity/reactivity and toxicity neutralization by the locally available equine therapeutic polyvalent BSV and VB antivenoms, and monovalent antivenom (OH-IgG) prepared in rabbit. None of the two therapeutic antivenoms procured from two different firms showed any signs of cross-reactivity in terms of antigen-antibody precipitin lines in immunodouble diffusion assay; however, a weak and an insignificant cross-reactivity pattern was observed in ELISA and Western blot studies. Further, both BSV and VB antivenoms failed to neutralize proteolytic, hyaluronidase and phospholipase activities as well as toxic properties such as edema, myotoxicity and lethality of the venom. As expected, OH-IgG showed strong reactivity in immunodouble diffusion, ELISA and in Western blot analysis and also neutralized both enzyme activities as well as the toxic properties of the venom. Thus, the study provides insight into the likely measures that are to be taken in cases of accidental king cobra bites for which the Indian subcontinent is still not prepared for.


Assuntos
Antivenenos/uso terapêutico , Reações Cruzadas , Elapidae , Mordeduras de Serpentes/tratamento farmacológico , Venenos de Serpentes/imunologia , Animais , Antivenenos/química , Ensaio de Imunoadsorção Enzimática , Acessibilidade aos Serviços de Saúde , Cavalos , Humanos , Índia , Coelhos , Mordeduras de Serpentes/imunologia
12.
J Pineal Res ; 56(3): 295-312, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24499241

RESUMO

Viper bites cause high morbidity and mortality worldwide and regarded as a neglected tropical disease affecting a large healthy population. Classical antivenom therapy has appreciably reduced the snakebite mortality rate; it apparently fails to tackle viper venom-induced local manifestations that persist even after the administration of antivenom. Recently, viper venom-induced oxidative stress and vital organ damage is deemed as yet another reason for concern; these are considered as postmedicated complications of viper bite. Thus, treating viper bite has become a challenge demanding new treatment strategies, auxiliary to antivenin therapy. In the last decade, several studies have reported the use of plant products and clinically approved drugs to neutralize venom-induced pharmacology. However, very few attempts were undertaken to study oxidative stress and vital organ damage. Based on this background, the present study evaluated the protective efficacy of melatonin in Echis carinatus (EC) venom-induced tissue necrosis, oxidative stress, and organ toxicity. The results demonstrated that melatonin efficiently alleviated EC venom-induced hemorrhage and myonecrosis. It also mitigated the altered levels of inflammatory mediators and oxidative stress markers of blood components in liver and kidney homogenates, and documented renal and hepatoprotective action of melatonin. The histopathology of skin, muscle, liver, and kidney tissues further substantiated the overall protection offered by melatonin against viper bite toxicities. Besides the inability of antivenoms to block local effects and the fact that melatonin is already a widely used drug promulgating a multitude of therapeutic functionalities, its use in viper bite management is of high interest and should be seriously considered.


Assuntos
Melatonina/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Mordeduras de Serpentes/tratamento farmacológico , Animais , Radicais Livres/metabolismo , Hemorragia/prevenção & controle , Mediadores da Inflamação/sangue , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Melatonina/administração & dosagem , Melatonina/farmacologia , Camundongos , Músculo Esquelético/patologia , Necrose/prevenção & controle , Ratos Wistar , Venenos de Víboras/toxicidade
13.
Arch Toxicol ; 88(2): 185-98, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24363025

RESUMO

The surfacing of the applied fields of biology such as, biotechnology, pharmacology and drug discovery was a boon to the modern man. However, it had its share of disadvantages too. The indiscriminate use of antibiotics and other biological drugs resulted in numerous adverse reactions including thrombocytopenia. One of the reasons for drug-induced thrombocytopenia could be attributed to an enhanced rate of platelet apoptosis, which is a less investigated aspect. The present essay sheds light on the adverse (pro-apoptotic) effects of some of the commonly used drugs and antibiotics on platelets viz. cisplatin, aspirin, vancomycin and balhimycin. Furthermore, the undesirable reactions resulting from chemotherapy could be attributed at least to some extent to the systemic stress induced by microparticles, which in turn are the byproducts of platelet apoptosis. Thereby, the essay aims to highlight the challenges in the emerging trend of cross-disciplinary implications, i.e., drug-induced platelet apoptosis, which is a nascent field. Thus, the different mechanisms through which drugs induce platelet apoptosis are discussed, which also opens up a new perspective through which the adverse effects of commonly used drugs could be dealt. The drug-associated platelet toxicity is of grave concern and demands immediate attention. Besides, it would also be appealing to examine the platelet pro-apoptotic effects of other commonly used therapeutic drugs.


Assuntos
Apoptose/efeitos dos fármacos , Plaquetas/efeitos dos fármacos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Trombocitopenia/induzido quimicamente , Aspirina/efeitos adversos , Plaquetas/ultraestrutura , Cisplatino/efeitos adversos , Humanos , Farmacovigilância , Trombocitopenia/patologia , Vancomicina/efeitos adversos , Vancomicina/análogos & derivados
14.
Anticancer Agents Med Chem ; 14(7): 975-83, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24372526

RESUMO

In current scenario of human health and diseases, drug-induced hepatic injury has been recognized as a serious and unresolved problem. Particularly, chemotherapeutic agents have been reported to induce organ toxicity. The aim of the present study is to evaluate organ toxicity and oxidative damage induced by cyclophosphamide (CP), a chemotherapeutic drug and its amelioration by sesamol, an antioxidant from sesame seeds. CP (150 mg/kg) is injected intraperitonially to experimental rats and from day 2 rats were orally treated with sesamol. Rats were sacrificed to evaluate non-enzymatic and enzymatic oxidative stress parameters in serum and tissue homogenates on day 8. Besides, liver function parameters and pro-inflammatory mediators were assessed. Histopathological studies of liver and kidney were also carried out. Elevated levels of endogenous reactive oxygen species, lipid peroxidation and decreased levels of glutathione, total thiols, along with the reduction in antioxidant enzymes including superoxide dismutase, catalase, glutathione-stransferase and glutathione peroxidase, were evident in CP-intoxicated animals. Pro-inflammatory mediators like tumor necrosis factor - α, interleukin (IL)-1ß, IL-6 and cyclooxygenase-2 were also elevated. Moreover, the levels of liver function markers like serum alanine aminotransferase and aspartate aminotransferase were also altered. Histology of liver and kidney tissues further supported CP-induced organ damage. Altered parameters were significantly restored to normal by oral administration of sesamol (50 mg/kg) suggesting its antioxidative stress, anti-inflammatory and hepatoprotective abilities. The study clearly demonstrated the potentiality of sesamol against CPinduced organ toxicity and oxidative stress suggesting its applicability in treatment regime of cancer and other stress-associated disorders as a supportive/auxiliary therapy.


Assuntos
Antineoplásicos Alquilantes/toxicidade , Antioxidantes/farmacologia , Benzodioxóis/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Ciclofosfamida/toxicidade , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fenóis/farmacologia , Animais , Biomarcadores/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Citocinas/metabolismo , Peróxido de Hidrogênio/metabolismo , Inflamação/metabolismo , Rim/metabolismo , Rim/patologia , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Baço/metabolismo , Baço/patologia
15.
Biochimie ; 95(11): 2060-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23933095

RESUMO

Platelets play an indispensable role in human health and disease. Platelets are very sensitive to oxidative stress, as it leads to the damage of mitochondrial DNA, which is the initial step of a sequence of events culminating in the cell death through the intrinsic pathway of apoptosis. Owing to a lot of reports on secondary complications arising from oxidative stress caused by therapeutic drug overdose, the present study concentrated on the influence of sesamol on oxidative stress-induced platelet apoptosis. Sesamol, a phenolic derivative present in sesame seeds is an exceptionally promising drug with lots of reports on its protective functions, including its inhibitory effects on platelet aggregation at concentrations below 100 µM, and its anti-cancer effect at 1 mM. However, the present study explored the toxic effects of sesamol on human platelets. Sesamol at the concentration of 0.25 mM and above induced platelet apoptosis through endogenous generation of ROS, depletion of thiol pool, and Ca(2+) mobilization. It also induced mitochondrial membrane potential depolarization, caspase activation, cytochrome c translocation and phosphatidylserine exposure, thus illustrating the pro-apoptotic effect of sesamol at higher concentration. However, even at high concentration of 2 mM sesamol effectively inhibited collagen/ADP/epinephrine-induced platelet aggregation. The study demonstrates that even though sesamol inhibits platelet aggregation, it has the tendency to elicit platelet apoptosis at higher concentrations. Sesamol has a potential as thrombolytic agent, nevertheless the current work highlights the significance of an appropriate dosage of sesamol when it is used as a therapeutic drug.


Assuntos
Apoptose/efeitos dos fármacos , Benzodioxóis/farmacologia , Estresse Oxidativo , Fenóis/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes , Plaquetas/metabolismo , Plaquetas/patologia , Caspase 3/metabolismo , Caspase 9/metabolismo , Citocromos c/metabolismo , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia
16.
Inflamm Res ; 62(7): 721-31, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23657249

RESUMO

BACKGROUND AND OBJECTIVE: The snakebite mortality rate has been significantly reduced due to effective anti-venin therapy. The intravenously infused anti-venom will neutralize free and target-bound toxins but fails to neutralize venom-induced inflammation and oxidative stress, as the antigen-antibody complex itself is pro-inflammatory. Therefore, an auxiliary therapy is necessary to treat secondary/overlooked envenomation complications. MATERIALS AND METHODS: Blood samples from healthy donors were treated with viper venom (100 µg/ml) for 2 h. The venom-induced inflammation, oxidative damage and effect of crocin pre-treatment were determined by assessing the serum levels of cytoplasmic, lysosomal and oxidative stress markers along with pro-inflammatory mediators such as tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6 and cyclo-oxygenase (COX)-2. RESULTS: Significantly increased stress markers, cytoplasmic, lysosomal and extracellular matrix-degrading enzymes as well as the pro-inflammatory mediators TNF-α, IL-1ß, IL-6 and COX-2 indicated increased cellular damage but significantly reduced oxidative damage and inflammation in crocin pre-treated groups. CONCLUSION: The data clearly suggest that venom-induced oxidative stress and inflammation is also responsible for oxidative burst and cell death in the circulation, which may worsen even after anti-venin therapy. Hence, the current study demands a supportive therapy in addition to anti-venin therapy to neutralize the overlooked issues of snakebite.


Assuntos
Citocinas/metabolismo , Estresse Oxidativo , Mordeduras de Serpentes , Venenos de Víboras/farmacologia , Fosfatase Alcalina/metabolismo , Antioxidantes/farmacologia , Carotenoides/farmacologia , Catalase/metabolismo , Ciclo-Oxigenase 2/metabolismo , Glutationa/metabolismo , Glicosídeo Hidrolases/metabolismo , Humanos , Hialuronoglucosaminidase/metabolismo , L-Lactato Desidrogenase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Soro/metabolismo , Compostos de Sulfidrila/metabolismo , Superóxido Dismutase/metabolismo
17.
Free Radic Res ; 47(5): 357-67, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23472882

RESUMO

In the present human health scenario, implication of oxidative stress in numerous pathologies including neurodegenerative, cardiovascular, liver, renal, pulmonary disorders, and cancer has gained attention. N-Acetylcysteine (NAC), a popular thiol antioxidant, has been clinically used to treat various pathophysiological disorders. However, NAC therapy is routine only in paracetamol intoxication and as a mucolytic agent. Over six decades, numerous studies involving NAC therapy have yielded inconsistent results, and this could be due to low bioavailability. In order to overcome the limitations of NAC, an amide derivative N-Acetylcysteine amide (NACA) has been synthesized to improve the lipophilicity, membrane permeability, and antioxidant property. Recent studies have demonstrated the blood-brain barrier permeability and therapeutic potentials of NACA in neurological disorders including Parkinson's disease, Alzheimer's disease, Multiple sclerosis, Tardive dyskinesia, and HIV-associated neurological disorders. In addition, NACA displays protective effect against pulmonary inflammation and antibiotic-induced apoptosis. Forthcoming research on the possible therapeutic properties of NACA and its generics in the management of pathologies associated with extracellular matrix degradation and oxidative stress-related inflammation is highly exiting. Superior bioavailability of NACA is likely to fulfill the promises of NAC as well as a molecule to improve the endurance and resident time of bioscaffolds and biomaterials. Till date, more than 800 reviews on NAC have been published. However, no comprehensive review is available on the therapeutic applications of NACA. Therefore, the current review would be the first to emphasize the therapeutic potentials of NACA and its derivatives.


Assuntos
Acetilcisteína/análogos & derivados , Antioxidantes/administração & dosagem , Tratamento Farmacológico/métodos , Estresse Oxidativo/efeitos dos fármacos , Acetilcisteína/administração & dosagem , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Glutationa/metabolismo , Humanos , Espécies Reativas de Oxigênio/metabolismo
18.
Biochimie ; 95(6): 1326-35, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23485680

RESUMO

Coumarins are a group of natural compounds widely distributed in plants. Of late, coumarins and their derivatives have grabbed much attention from the pharmacological and pharmaceutical arena due to their broad range of therapeutical qualities. A coumarin derivative 4-methylesculetin (4-ME) has known to possess effective antioxidant and radical-scavenging properties. Recently they have also shown to down regulate nuclear factor-kappa B (NF-κB) and protein kinase B (Akt) that play a vital role in inflammation and apoptosis. In view of this, the present study investigated the anti-arthritic potentiality of 4-ME by assessing its ability to inhibit cartilage and bone degeneration, inflammation and associated oxidative stress. Arthritis being a debilitating joint disease, results in the deterioration of extracellular matrix (ECM) of cartilage and synovium. Participation of both enzymatic and non-enzymatic factors in disease perpetuation is well documented. The present study demonstrated the mitigation of augmented serum levels of hyaluronidase and matrix metalloproteinases (MMP-13, MMP-3 and MMP-9) responsible for cartilage degeneration by 4-ME. It also protected bone resorption by reducing the elevated levels of bone-joint exoglycosidases, cathepsin-D and tartrate resistant acid phosphatases. Further, 4-ME significantly ameliorated the upregulated non-enzymatic inflammatory markers like TNF-α, IL-1ß, IL-6, COX-2 and PGE2. Besides, 4-ME effectively stabilized the arthritis-induced oxidative stress by restoring the levels of reactive oxygen species, lipid and hydro peroxides and antioxidant enzymes such as superoxide dismutase, catalase and glutathione-S-transferase. Thus, the study suggests that 4-ME could be an effective agent to treat arthritis and associated secondary complications like oxidative stress.


Assuntos
Anti-Inflamatórios/farmacologia , Artrite Experimental/tratamento farmacológico , Osso e Ossos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Umbeliferonas/farmacologia , Animais , Artrite Experimental/patologia , Osso e Ossos/patologia , Cartilagem/efeitos dos fármacos , Cartilagem/patologia , Cumarínicos/química , Modelos Animais de Doenças , Inflamação/patologia , Masculino , Ratos , Ratos Wistar
19.
J Thromb Thrombolysis ; 36(4): 424-32, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23412973

RESUMO

Viper envenomations are characterized by prominent local and systemic manifestations including hematological alterations. Snake venom metalloproteinases (SVMPs) and phospholipase A2 (PLA2) plays crucial role in the pathophysiology of hemorrhage by targeting/altering the platelets function which may result in thrombocytopenia. Platelets undergo the classic events of mitochondria-mediated apoptotic pathway due to augmented endogenous reactive oxygen species (ROS) levels. The observed anticoagulant effects during viper envenomations could be due to exacerbated platelet apoptosis and thrombocytopenia. Moreover, antivenin treatments are ineffective against the venom-induced oxidative stress; therefore, it necessitates an auxiliary therapy involving antioxidants which can effectively scavenge the endothelium-generated/endogenous ROS and protect the platelets. The present study explored the effects of viper venom on platelet apoptosis and its amelioration by a phytochemical crocin. The study evaluated the Vipera russelli venom-induced apoptotic events including endogenous ROS generation, intracellular Ca(2+) mobilization, mitochondrial membrane depolarization, cyt-c translocation, caspase activation and phosphatidylserine externalization which were effectively mitigated when the venom was pre-treated with crocin. The study highlights one of the less studied features of venom-induced secondary complications i.e. platelet apoptosis and sheds light on the underlying basis for venom-induced thrombocytopenia, systemic hemorrhage and in vivo anticoagulant effect.


Assuntos
Apoptose/efeitos dos fármacos , Plaquetas/metabolismo , Carotenoides/farmacologia , Crocus/química , Mordeduras de Serpentes/tratamento farmacológico , Trombocitopenia/tratamento farmacológico , Venenos de Víboras/toxicidade , Viperidae , Animais , Plaquetas/patologia , Carotenoides/química , Feminino , Humanos , Masculino , Mordeduras de Serpentes/sangue , Mordeduras de Serpentes/patologia , Trombocitopenia/etiologia , Trombocitopenia/metabolismo , Trombocitopenia/patologia
20.
Int J Biol Macromol ; 55: 39-46, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23305704

RESUMO

Hyaluronidase inhibitors have immense applications in pathophysiological conditions associated with hyaluronan-hyaluronidase system. The present study demonstrates the inhibitory efficacy of clinically accepted antioxidant N-acetyl cysteine (NAC) against hyaluronidase of serum, testis, and snake and bee venoms. The experimental and molecular dynamic simulation data suggest the non-competitive inhibition and involvement of thiol groups of both NAC and glutathione in exertion of inhibition. The bioavailability, less-toxic and antioxidant nature of NAC and glutathione could become valuable in the management of pathologies triggered by extracellular matrix degradation and to increase the endurance of hyaluronan based biomaterials/supplements, which are highly exciting aspects.


Assuntos
Acetilcisteína/farmacologia , Glutationa/farmacologia , Hialuronoglucosaminidase/antagonistas & inibidores , Acetilcisteína/química , Acetilcisteína/metabolismo , Animais , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Glutationa/química , Glutationa/metabolismo , Hialuronoglucosaminidase/química , Hialuronoglucosaminidase/metabolismo , Cinética , Conformação Molecular , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Ligação Proteica
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