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2.
Free Radic Res ; 52(10): 1140-1157, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30422019

RESUMO

Inflammation is a protective immune response against invading pathogens, however, dysregulated inflammation is detrimental. As the complex inflammatory response involves multiple mediators, including the involvement of reactive oxygen species, concomitantly targeting proinflammatory and antioxidant check-points may be a more rational strategy. We report the synthesis and anti-inflammatory/antioxidant activity of a novel indanedione derivative DMFO. DMFO scavenged reactive oxygen species (ROS) in in-vitro radical scavenging assays and in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. In acute models of inflammation (carrageenan-induced inflammation in rat paw and air pouch), DMFO effectively reduced paw oedema and leucocyte infiltration with an activity comparable to diclofenac. DMFO stabilised mast cells (MCs) in in-vitro A23187 and compound 48/80-induced assays. Additionally, DMFO stabilised MCs in an antigen (ovalbumin)-induced MC degranulation model in-vivo, without affecting serum IgE levels. In a model of chronic immune-mediated inflammation, Freund's adjuvant-induced arthritis, DMFO reduced arthritic score and contralateral paw oedema, and increased the pain threshold with an efficacy comparable to diclofenac but without being ulcerogenic. Additionally, DMFO significantly reduced serum TNFα levels. Mechanistic studies revealed that DMFO reduced proinflammatory genes (IL1ß, TNFα, IL6) and protein levels (COX2, MCP1), with a concurrent increase in antioxidant genes (NQO1, haem oxygenase 1 (HO-1), Glo1, Nrf2) and protein (HO-1) in LPS-stimulated macrophages. Importantly, the anti-inflammatory/antioxidant effect on gene expression was absent in primary macrophages isolated from Nrf2 KO mice suggesting an Nrf2-targeted activity, which was subsequently confirmed using siRNA transfection studies in RAW macrophages. Therefore, DMFO is a novel, orally-active, safe (even at 2 g/kg p.o.), a small molecule which targets Nrf2 in ameliorating inflammation.


Assuntos
Antioxidantes/metabolismo , Indanos/farmacologia , Inflamação/tratamento farmacológico , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Benzotiazóis/antagonistas & inibidores , Benzotiazóis/metabolismo , Compostos de Bifenilo/antagonistas & inibidores , Compostos de Bifenilo/metabolismo , Carragenina , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Edema/induzido quimicamente , Edema/tratamento farmacológico , Indanos/síntese química , Indanos/química , Inflamação/metabolismo , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Mastócitos , Camundongos , Camundongos Knockout , Fator 2 Relacionado a NF-E2/deficiência , Fator 2 Relacionado a NF-E2/metabolismo , Picratos/antagonistas & inibidores , Picratos/metabolismo , Células RAW 264.7 , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/química , Ácidos Sulfônicos/antagonistas & inibidores , Ácidos Sulfônicos/metabolismo
3.
Front Physiol ; 9: 114, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29515457

RESUMO

It is now increasingly appreciated that inflammation is not limited to the control of pathogens by the host, but rather that sterile inflammation which occurs in the absence of viral or bacterial pathogens, accompanies numerous disease states, none more so than the complications that arise as a result of hyperglycaemia. Individuals with type 1 or type 2 diabetes mellitus (T1D, T2D) are at increased risk of developing cardiac and vascular complications. Glucose and blood pressure lowering therapies have not stopped the advance of these morbidities that often lead to fatal heart attacks and/or stroke. A unifying mechanism of hyperglycemia-induced cellular damage was initially proposed to link elevated blood glucose levels with oxidative stress and the dysregulation of metabolic pathways. Pre-clinical evidence has, in most cases, supported this notion. However, therapeutic strategies to lessen oxidative stress in clinical trials has not proved efficacious, most likely due to indiscriminate targeting by antioxidants such as vitamins. Recent evidence now suggests that oxidative stress is a major driver of inflammation and vice versa, with the latest findings suggesting not only a key role for inflammatory pathways underpinning metabolic and haemodynamic dysfunction in diabetes, but furthermore that these perturbations are driven by activation of the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome. This review will address these latest findings with an aim of highlighting the interconnectivity between oxidative stress, NLRP3 activation and inflammation as it pertains to cardiac and vascular injury sustained by diabetes. Current therapeutic strategies to lessen both oxidative stress and inflammation will be emphasized. This will be placed in the context of improving the burden of these diabetic complications.

4.
Eur J Pharm Sci ; 111: 320-329, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29032304

RESUMO

From our lab, among the nineteen heterocyclic homoprostanoids (HHPs), three derivatives (compounds 3, 3b and 3c) exerted antioxidant and anti-inflammatory activity. Present study is an extension of the earlier work, and, is designed to establish their therapeutic potential in monoarthritis in rats. In addition, their possible mechanism of action would be investigated. A battery of in vitro tests such as lipopolysaccharide (LPS)-induced nitrite (NO)/reactive oxygen species (ROS) and NO/interleukin (IL)-6 generation in murine macrophages and whole blood (WhB), respectively were conducted. Later, in vitro cyclooxygenase (COX) enzyme inhibitory activity was also evaluated. All the tested compounds showed comparable efficacy against ROS and NO in LPS-stimulated murine macrophages. However, compound 3 did not exert inhibitory effect on LPS-induced NO/IL-6 generation in WhB assay. Compounds (3b and 3c) inhibited the NO generation in LPS-stimulated WhB. However, only compound 3b reversed the raised IL-6 levels in this assay. None of the test compounds inhibited COX iso-enzymes in the in vitro assay. All three HHPs showed comparable efficacy against carrageenan-induced paw inflammation. However, none of them exhibited any dose-dependent effect in this model. Based upon previous reports, compound 3c was explored against adjuvant-induced monoarthritis (AIA) in male Sprague-Dawley rats, where it exerted promising therapeutic effect. In addition to radiological and histological examinations of tibio-tarsal joint, various parameters such as chronic inflammation/pain, clinical score, interleukin (IL)-6 levels and complete blood cell profile were evaluated in AIA rats. Chronic treatment with 3c halted the disease progression in rats, improved the overall health of animals, as demonstrated by haematological, clinical scoring and joint examinations (radiological and histopathological). Inhibitory effect on elevated IL-6 in AIA rats suggested the possible mechanism of 3c on cytokine signalling. Overall, the study supports the anti-arthritic potential of compound 3c.


Assuntos
Artrite Experimental/tratamento farmacológico , Prostaglandinas/farmacologia , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Artrite Experimental/induzido quimicamente , Carragenina/toxicidade , Diclofenaco/uso terapêutico , Adjuvante de Freund/toxicidade , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Masculino , Camundongos , Estrutura Molecular , Prostaglandinas/química , Células RAW 264.7 , Ratos , Ratos Sprague-Dawley
5.
Clin Sci (Lond) ; 131(10): 981-990, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28473473

RESUMO

Oxidative stress is a consequence of up-regulation of pro-oxidant enzyme-induced reactive oxygen species (ROS) production and concomitant depletion of antioxidants. Elevated levels of ROS act as an intermediate and are the common denominator for various diseases including diabetes-associated macro-/micro-vascular complications and hypertension. A range of enzymes are capable of generating ROS, but the pro-oxidant enzyme family, nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (NOXs), are the only enzymes known to be solely dedicated to ROS generation in the vascular tissues, kidney, aortas and eyes. While there is convincing evidence for a role of NOX1 in vascular and eye disease and for NOX4 in renal injury, the role of NOX5 in disease is less clear. Although NOX5 is highly up-regulated in humans in disease, it is absent in rodents. Thus, so far it has not been possible to study NOX5 in traditional mouse or rat models of disease. In the present review, we summarize and critically analyse the emerging evidence for a pathophysiological role of NOX5 in disease including the expression, regulation and molecular and cellular mechanisms which have been demonstrated to be involved in NOX5 activation.


Assuntos
Proteínas de Membrana/metabolismo , NADPH Oxidases/metabolismo , Doenças Vasculares/enzimologia , Animais , Endotélio Vascular/enzimologia , Humanos , Proteínas de Membrana/genética , Camundongos , NADPH Oxidase 5 , NADPH Oxidases/genética , Ratos , Espécies Reativas de Oxigênio/metabolismo , Doenças Vasculares/genética
6.
Front Pharmacol ; 7: 381, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27790148

RESUMO

We had previously demonstrated the anti-diabetic potential and pancreatic protection of two thiazolidin-4-one derivatives containing nicotinamide moiety (NAT-1 and NAT-2) in STZ-induced diabetic mice. However, due to the limitations of the STZ model, we decided to undertake a detailed evaluation of anti-diabetic potential of the molecules on a high sucrose diet (HSD) fed diabetic mouse model. Further, in vitro mechanistic studies on the phosphorylation of AMPK, Akt and p38 MAP kinase in L6 myotubes and anti-inflammatory studies in RAW264.7 mouse monocyte macrophage cells were performed. 15 months of HSD induced fasting hyperglycaemia and impaired glucose tolerance in mice. Treatment with NAT-1 and NAT-2 (100 mg/kg) for 45 days significantly improved the glucose tolerance and lowered fasting blood glucose levels compared to untreated control. An improvement in the elevated triglycerides and total cholesterol levels, and favorable rise in HDL cholesterol were also observed with test drug treatment. Also, no major changes were observed in the liver (albumin, AST and ALT) and kidney (creatinine and urea) parameters. This was further confirmed in their respective histology profiles which revealed no gross morphological changes. In L6 cells, significant phosphorylation of Akt and p38 MAP kinase proteins were observed with 100 µM of NAT-1 and NAT-2 with no significant changes in phosphorylation of AMPK. The molecules failed to exhibit anti-inflammatory activity as observed by their effect on the generation of ROS and nitrite, and nuclear levels of NF-κB in LPS-stimulated RAW264.7 cells. In summary, the molecules activated Akt and p38 MAP kinase which could have partly contributed to their anti-hyperglycaemic and hypolipidemic activities in vivo.

7.
J Diabetes ; 8(5): 629-39, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26345135

RESUMO

BACKGROUND: The replacement of the thiazolidinedione moiety with a thiazolidinone may yield antidiabetic compounds with similar pleiotropic effects. Hence, the aim of the present study was to explore the dose-related antihyperglycemic and hypolipidemic effects of two synthesized novel thiazolidin-4-one derivatives, one with a nicotinamide and the other with a p-chlorophenoxyacetamide substitution at the N3 position of the thiazolidinone ring (NAT1 and PAT1, respectively), in a rodent model of metabolic syndrome (MetS). METHODS: Metabolic syndrome was induced in Wistar rats by neonatal administration of monosodium glutamate (i.p.) on 4 consecutive days followed by high-sucrose diet feeding for 6 months. The effects of NAT1 (33 and 66 mg/kg) and molar equivalent doses of PAT1 (40 and 80 mg/kg) on relevant biochemical parameters were evaluated. Because MetS is a state of chronic low-grade inflammation, we also evaluated the effects of these compounds on proinflammatory markers, namely interleukin (IL)-6, tumor necrosis factor (TNF)-α, reactive oxygen species (ROS), and nitric oxide (NO). RESULTS: Both NAT1 and PAT1 attenuated hyperglycemia, hypertriglyceridemia, hypoalphalipoproteinemia, and glucose intolerance. PAT1 exhibited superior antihyperglycemic and antihypoalphalipoproteinemic effects than NAT1. However, NAT1 had a better triglyceride-lowering effect. At the lower dose tested, both compounds significantly reduced elevated malondialdehyde levels. In addition, PAT1 (80 mg/kg) restored hepatic superoxide dismutase enzyme levels. There was a tendency for NAT1 and PAT1 to inhibit elevated hepatic IL-6 and TNF-α levels, but the differences did not reach statistical significance. In addition, PAT1 exhibited in vitro anti-inflammatory activity by reducing proinflammatory ROS and NO levels in RAW264.7 macrophages. CONCLUSIONS: The novel thiazolidin-4-ones NAT1 and PAT1 could be potential pleiotropic drug candidates targeting MetS.


Assuntos
Modelos Animais de Doenças , Hipoglicemiantes/farmacologia , Hipolipemiantes/farmacologia , Síndrome Metabólica/tratamento farmacológico , Tiazolidinas/farmacologia , Animais , Animais Recém-Nascidos , Glicemia/metabolismo , Linhagem Celular , Colesterol/sangue , Sacarose Alimentar/administração & dosagem , Sacarose Alimentar/efeitos adversos , Relação Dose-Resposta a Droga , Feminino , Hipoglicemiantes/química , Hipolipemiantes/química , Interleucina-6/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/etiologia , Estrutura Molecular , Óxido Nítrico/metabolismo , Estado Pré-Diabético/sangue , Estado Pré-Diabético/tratamento farmacológico , Estado Pré-Diabético/etiologia , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Glutamato de Sódio , Tiazolidinas/química , Triglicerídeos/sangue , Fator de Necrose Tumoral alfa/metabolismo
8.
Inflamm Res ; 64(10): 747-52, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26186905

RESUMO

Inflammation is a complex, metabolically expensive process involving multiple signaling pathways and regulatory mechanisms which have evolved over evolutionary timescale. Addressing multiple targets of inflammation holistically, in moderation, is probably a more evolutionarily viable strategy, as compared to current therapy which addresses drug targets in isolation. Polypharmacology, addressing multiple targets, is commonly used in complex ailments, suggesting the superior safety and efficacy profile of multi-target (MT) drugs. Phenotypic drug discovery, which generated successful MT and first-in-class drugs in the past, is now re-emerging. A multi-pronged approach, which modulates the evolutionarily conserved, robust and pervasive cellular mechanisms of tissue repair, with AMPK at the helm, regulating the complex metabolic/immune/redox pathways underlying inflammation, is perhaps a more viable strategy than addressing single targets in isolation. Molecules that modulate multiple molecular mechanisms of inflammation in moderation (modulating TH cells toward the anti-inflammatory phenotype, activating AMPK, stimulating Nrf2 and inhibiting NFκB) might serve as a model for a novel Darwinian "first-in-class" therapeutic category that holistically addresses immune, redox and metabolic processes associated with inflammatory repair. Such a multimodal biological activity is supported by the fact that several non-calorific pleiotropic natural products with anti-inflammatory action have been incorporated into diet (chiefly guided by the adaptive development of olfacto-gustatory preferences over evolutionary timescales) rendering such molecules, endowed with evolutionarily privileged molecular scaffolds, naturally oriented toward multiple targets.


Assuntos
Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Inflamação/tratamento farmacológico , Descoberta de Drogas , Humanos
9.
Indian J Pharmacol ; 46(5): 521-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25298582

RESUMO

OBJECTIVE: 1,3,4-oxadiazole ring is a versatile moiety with a wide range of pharmacological properties. The present work deals with the synthesis and evaluation of the anti-inflammatory activity of two novel 2,5-disubstituted-1,3,4-oxadiazoles (OSD and OPD). MATERIALS AND METHODS: Carrageenan-induced rat hind paw edema was employed as an acute model of inflammation. For evaluating sub-acute anti-inflammatory activity, carrageenan-induced inflammation in rat air pouch was employed. Complete Freund's adjuvant-induced arthritis in rats was used as a model of chronic inflammation. To evaluate in vitro anti-inflammatory activity, lipopolysaccharide (LPS)-stimulated RAW264.7 cells were used. RESULTS: OSD (100 mg/kg) reduced carrageen-induced paw edema by 60%, and OPD (100 mg/kg) produced a modest 32.5% reduction. OSD also reduced leukocyte influx and myeloperoxidase in carrageenan-induced rat air pouch model. In complete Freund's adjuvant-induced arthritis model, both OSD and OPD (200 mg/kg for 14 days) reduced paw edema and NO levels. In LPS-stimulated RAW264.7 cells, OSD and OPD inhibited formation of nitric oxide and reactive oxygen species, with OPD showing a better activity in comparison to OSD. CONCLUSIONS: OSD was the better of the two compounds in in vivo models of inflammation. The o-phenol substitution at position 2 of oxadiazole ring in OSD may be responsible for its better in vivo anti-inflammatory activity. The ability of the compounds to inhibit LPS-induced pro-inflammatory mediator release suggests an anti-inflammatory mechanism targeting LPS-TLR4-NF-κB signalling pathway, which needs to be explored in detail. The disparate efficacy in vitro and in vivo also requires in-depth evaluation of the pharmacokinetics of these novel oxadiazoles.


Assuntos
Anti-Inflamatórios/farmacologia , Artrite Experimental/tratamento farmacológico , Inflamação/tratamento farmacológico , Oxidiazóis/farmacologia , Animais , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Artrite Experimental/patologia , Carragenina , Linhagem Celular , Modelos Animais de Doenças , Edema/tratamento farmacológico , Adjuvante de Freund , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/toxicidade , Óxido Nítrico/metabolismo , Oxidiazóis/síntese química , Oxidiazóis/química , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos
10.
Pharmacol Rep ; 66(5): 788-98, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25149982

RESUMO

BACKGROUND: Silymarin, a hepatoprotective agent, has poor oral bioavailability. However, the current dosage form of the drug does not target the liver and inflammatory cells selectively. The aim of the present study was to develop lecithin-based carrier system of silymarin by incorporating phytosomal-liposomal approach to increase its oral bioavailability and to make it target-specific to the liver for enhanced hepatoprotection. METHODS: The formulation was prepared by film hydration method. Release of drug was assessed at pH 1.2 and 7.4. Formulation was assessed for in vitro hepatoprotection on Chang liver cells, lipopolysaccharide-induced reactive oxygen species (ROS) production by RAW 267.4 (murine macrophages), in vivo efficacy against paracetamol-induced hepatotoxicity and pharmacokinetic study by oral route in Wistar rat. RESULTS: The formulation showed maximum entrapment (55%) for a lecithin-cholesterol ratio of 6:1. Comparative release profile of formulation was better than silymarin at pH 1.2 and pH 7.4. In vitro studies showed a better hepatoprotection efficacy for formulation (one and half times) and better prevention of ROS production (ten times) compared to silymarin. In in vivo model, paracetamol showed significant hepatotoxicity in Wistar rats assessed through LFT, antioxidant markers and inflammatory markers. The formulation was found more efficacious than silymarin suspension in protecting the liver against paracetamol toxicity and the associated inflammatory conditions. The liposomal formulation yielded a three and half fold higher bioavailability of silymarin as compared with silymarin suspension. CONCLUSIONS: Incorporating the phytosomal form of silymarin in liposomal carrier system increased the oral bioavailability and showed better hepatoprotection and better anti-inflammatory effects compared with silymarin suspension.


Assuntos
Hepatócitos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Silimarina/administração & dosagem , Acetaminofen/toxicidade , Administração Oral , Animais , Disponibilidade Biológica , Linhagem Celular , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Liberação Controlada de Fármacos , Hepatócitos/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Lipopolissacarídeos/farmacologia , Lipossomos , Fígado/citologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Macrófagos/metabolismo , Masculino , Camundongos , Substâncias Protetoras/administração & dosagem , Substâncias Protetoras/farmacocinética , Ratos , Ratos Wistar , Silibina , Silimarina/farmacocinética
11.
ScientificWorldJournal ; 2014: 802701, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24616646

RESUMO

BACKGROUND: Inflammatory bowel disease (IBD) is a chronic inflammatory disorder of gastrointestinal tract of immune, genetic, and environmental origin. In the present study, we examined the effects of sesamol (SES), which is the active constituent of sesame oil in the acetic acid (AA) induced model for IBD in rats. METHODS: The groups were divided into normal control, AA control, SES, and sulfasalazine (SS). On day 7, the rats were killed, colon was removed, and the macroscopic, biochemical, and histopathological evaluations were performed. RESULTS: The levels of MPO, TBARS, and tissue nitrite increased significantly (P < 0.05) in the AA group whereas they reduced significantly in the SES and SS treated groups. Serum nitrite levels were found to be insignificant between the different groups. CONCLUSIONS: The mucosal protective effects of sesamol in IBD are due to its potential to reduce the myeloperoxidase and nitrite content.


Assuntos
Ácido Acético/toxicidade , Benzodioxóis/uso terapêutico , Colo/efeitos dos fármacos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Peroxidase/metabolismo , Fenóis/uso terapêutico , Animais , Benzodioxóis/farmacologia , Colo/enzimologia , Feminino , Doenças Inflamatórias Intestinais/induzido quimicamente , Doenças Inflamatórias Intestinais/enzimologia , Fenóis/farmacologia , Ratos , Ratos Wistar
12.
Chem Biol Interact ; 210: 34-42, 2014 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-24412305

RESUMO

Three thiazolidin-4-one derivatives were synthesized, purified and characterized by chromatographic and spectroscopic methods. In the in vitro assays, these compounds inhibited reactive oxygen species (ROS), nitrite and cytokine generation in RAW 264.7 murine macrophages and whole blood. These derivatives attenuated carrageenan-induced acute inflammation in rats. The most effective compound 4C possessed identical anti-inflammatory action at two doses (50 and 100 mg/kg). Further, the effect of compound 4C on locally induced inflammatory mediators was investigated in carrageenan-induced air pouch inflammation in rats. In this model, compound 4C inhibited the cytokines, tumor necrosis factor (TNF)-α and interleukin (IL)-6 (systemic and local). Additionally, compound 4C was able to reduce locally elevated prostaglandin-E2 (PGE2). Inhibition of leukocyte infiltration by compound 4C was correlated with reduced locally released myeloperoxidase (MPO). To conclude, compound 4C corrected the inflammatory condition by negative effect on cytokine (TNF-α, IL-6) network and prostaglandin-E2 generation.


Assuntos
Anti-Inflamatórios/farmacologia , Inflamação/induzido quimicamente , Macrófagos/efeitos dos fármacos , Tiazolidinas/farmacologia , Animais , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Western Blotting , Carragenina , Linhagem Celular , Ciclo-Oxigenase 1/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Inflamação/sangue , Macrófagos/imunologia , Camundongos , Modelos Moleculares , Estrutura Molecular , Ratos , Ratos Sprague-Dawley , Tiazolidinas/síntese química , Tiazolidinas/química
13.
EXCLI J ; 13: 1055-74, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26417321

RESUMO

Synthetic 3-hydroxyflavone analogues (JY-1, JY-2, JY-3, JY-4), were tested for antidiabetic activity in high-fructose-diet-fed (66 %, for 6 weeks) insulin-resistant Wistar rats (FD-fed rats). The fasting blood glucose, insulin, creatinine and AGEs were decreased to near normal upon treatment with test compounds. Insulin resistance markers such as HOMA-IR, K-ITT, plasma triglycerides, lipids, endogenous antioxidant defense and glycogen were restored in FD-fed rats after treatment with 3-hydroxyflavones. It is known that insulin resistance is partly because of oxidative stress and hence antioxidant activity was determined. They exhibited significant in vitro DPPH and ABTS radical scavenging activity (IC50: 10.66-66.63 µM). Test compounds inhibited ROS and NO production in RAW 264.7 cells (IC50: 10.39-42.63 µM) and they were found as potent as quercetin. Further, the test compounds inhibited lipid peroxidation at low concentrations (IC50: 99.61-217.47 µM). All test compounds at concentrations 100-200 µM protected calf thymus DNA-damage by Fenton reaction. In addition, test compounds inhibited protein glycation in different in vitro antiglycation assays. JY-2 showed maximum potency in all the stages of glycation which was comparable to the standard quercetin and aminoguanidine. Test compounds also enhanced the glucose uptake by L6 myotubes at an EC50 much lower than that of quercetin. Thus the synthetic 3-hydroxyflavones were found to have good antidiabetic activity by pleotropic and multimodal suppression of insulin resistance and enhancement of glucose uptake by skeletal muscles. These compounds are non-toxic at the doses tested. Further, the combined antioxidant and antiglycation activities of these molecules have complementary benefits in management of diabetes.

14.
Med Hypotheses ; 82(2): 159-62, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24355423

RESUMO

The conflict between our 'primitive' genes and 'modern' lifestyle probably lies at the root of several disorders that afflict modern man. Atherosclerosis, which is relatively unknown among contemporary hunter-gatherer populations, has reached pandemic proportions in recent times. Being an evolutionary problem with several inter-related pathologies, current therapeutic strategy for treating atherosclerosis has inherent limitations. Reviewing evolution-linked risk factors suggests that there are four aspects to the etiology of atherosclerosis namely, decreased intestinal parasitism, oversensitivity of evolutionarily redundant mast cells, chronic underactivation of AMPK (cellular energy sensor) and a deficiency of vitamin D. A combination of these four causes appear to have precipitated the atherosclerosis pandemic in modern times. Man and worms co-existed symbiotically in the past. Massive de-worming campaigns could have disrupted this symbiosis, increasing nutritional availability to man (pro-obesity) at the cost of decreased immunotolerance (pro-atherogenicity). A reduction in helminth-induced chronic TH2 activation could also have enhanced TH1 polarization, eventually disrupting the reciprocal regulation of TH1/TH2 balance and resulting in atherosclerosis. The riddance of helminth infestations may have rendered mast cells immunologically redundant, making them oversensitive to inflammatory stimuli, thereby playing a pro-atherogenic role. AMPK activation exerts pleiotropic anti-atherogenic effects, such as suppression of fatty acid, cholesterol, protein synthesis, reduction of vascular smooth muscle proliferation, etc. As energy deficit is the chief stimulus for AMPK activation, the over-nourished modern man appears to be suffering from chronic underactivation of AMPK, legitimising the unrivalled supremacy of metformin, the oldest prescribed antidiabetic drug. The fact that humans evolved in the sunny tropics suggests that humans are selected for high vitamin D levels. Vitamin D deficiency is now linked to several conditions including increased risk of CV disorders, diabetes, etc. The manifold decrease in vitamin D levels in modern man justifies a need for supplementation. We therefore hypothesize that a judicious combination of mast cell stabilization, AMPK activation, vitamin D supplementation, and moderation in hygiene practices could be an evolution-based multimodal strategy for both preventing and mitigating the pandemic of atherosclerosis.


Assuntos
Aterosclerose/terapia , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Evolução Biológica , Humanos , Higiene , Intestinos/parasitologia , Mastócitos/citologia , Metformina/química , Modelos Teóricos , Transdução de Sinais , Vitamina D/metabolismo , Deficiência de Vitamina D/complicações
15.
Pharmacol Rep ; 65(3): 658-65, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23950588

RESUMO

BACKGROUND: Inflammatory bowel disease (IBD) is a chronic inflammatory condition of gastrointestinal tract of immune, genetic and environmental origin. In the present study, we examined the effect of sesamol (SES), the main anti-oxidative constituent of Sesamum indicum (sesame seed) Linn. in the dinitrochlorobenzene (DNCB)-induced model for IBD in rats. METHODS: The groups were divided into normal control, DNCB control, SES and sulfasalazine (SS). On day 24, the rats were killed, colon removed and the macroscopic, biochemical and histopathological evaluations were performed. RESULTS: The levels of MPO, TBARS and nitrite increased significantly (p < 0.05) in the DNCB group, whereas reduced significantly in the SES, SS treated groups. Serum nitrite levels were found to be insignificant between the different groups. IL-6 and TNF-α levels were significantly high in the DNCB group. CONCLUSIONS: We conclude the mucosal protective effect of SES on colon due to its potent antioxidant actions. Further investigation is required in a chronic model of different rodent strain for its role involved in the cytokine pathway.


Assuntos
Benzodioxóis/farmacologia , Dinitroclorobenzeno/efeitos adversos , Doenças Inflamatórias Intestinais/induzido quimicamente , Doenças Inflamatórias Intestinais/tratamento farmacológico , Fenóis/farmacologia , Animais , Antioxidantes/farmacologia , Peso Corporal/efeitos dos fármacos , Colo , Fator Estimulador de Colônias de Granulócitos/metabolismo , Doenças Inflamatórias Intestinais/sangue , Doenças Inflamatórias Intestinais/metabolismo , Interleucina-3/metabolismo , Interleucina-6/metabolismo , Masculino , Nitritos/sangue , Nitritos/metabolismo , Ratos , Ratos Wistar , Proteínas Recombinantes de Fusão/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
16.
Int Immunopharmacol ; 15(1): 182-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23159605

RESUMO

6b,11b-Dihydroxy-6b,11b-dihydro-7H-indeno[1,2-b]naphtho[2,1-d]furan-7-one (DHFO), an easily synthesisable, orally bioavailable and relatively non-toxic small molecule synthesised in our lab, was previously reported to possess anti-oxidant, 5-lipoxygenase inhibitory, anti-inflammatory and peripheral analgesic activities. The present work deals with exploration of DHFO's efficacy in immunopathogenic chronic inflammatory conditions - arthritis and allergy. In carrageenan-induced inflammatory air pouch, which resembles the arthritic synovium, DHFO effectively reduced inflammatory redness and swelling and neutrophil infiltration. In complete Freund's adjuvant-induced arthritis, DHFO significantly decreased paw oedema and nitrite levels with efficacy comparable to diclofenac. DHFO inhibited neutrophil activation (observed as decreased myeloperoxidase levels), in both the in vivo models of inflammation. Interestingly, DHFO did not ulcerate the gastrointestinal tract, while diclofenac was observed to be extremely ulcerogenic. In antigen-induced active and passive anaphylaxis (allergy) models, DHFO dose-dependently prevented mesenteric mast cell (MC) degranulation with efficacy comparable to ketotifen. DHFO also inhibited compound 48/80 (C48/80)-induced paw oedema and peritoneal MC degranulation. DHFO stabilised p815 murine MCs stimulated by C48/80 and calcium ionophore-A23187, indicating an action downstream of calcium mobilisation. DHFO's anti-allergic mechanism could be two-pronged involving (1) inhibition of IgE production and/or (2) MC stabilisation. DHFO inhibited lipopolysaccharide (LPS)-induced pro-inflammatory mediator release (ROS, NO, IL-6 levels) and COX2 expression in RAW264.7 murine macrophages. Protein expression studies confirmed DHFO's ability to reduce nuclear levels of NF-κB in LPS-stimulated macrophages. Thus, DHFO is a promising non-ulcerogenic synthetic small molecule lead for immunopathogenic chronic inflammatory conditions.


Assuntos
Anti-Inflamatórios/uso terapêutico , Artrite/tratamento farmacológico , Furanos/uso terapêutico , Hipersensibilidade/tratamento farmacológico , Indenos/uso terapêutico , Naftalenos/uso terapêutico , Animais , Antígenos/imunologia , Artrite/metabolismo , Carragenina , Linhagem Celular , Ciclo-Oxigenase 2/metabolismo , Edema/tratamento farmacológico , Adjuvante de Freund , Furanos/farmacologia , Liberação de Histamina/efeitos dos fármacos , Hipersensibilidade/metabolismo , Indenos/farmacologia , Inflamação/tratamento farmacológico , Interleucina-6/metabolismo , Camundongos , NF-kappa B/metabolismo , Naftalenos/farmacologia , Óxido Nítrico/metabolismo , Peroxidase/metabolismo , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Soro/imunologia , Ovinos , p-Metoxi-N-metilfenetilamina
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