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Several mediators were associated with the pathogenesis of inflammatory bowel disease such as oxidative stress through the production of reactive oxygen metabolites, neutrophils infiltration and release of pro-inflammatory cytokines. This study was designed to investigate the therapeutic efficacy of osthole against dinitrobenzene sulfonic acid (DNBS) induced-colitis in rats through its anti-oxidant and anti-inflammatory properties. Colitis was induced in rats by single intracolonic instillation of (250 μl DNBS-25 mg/rat). Then 4 days later, rats were received oral administration of either (osthole 50 mg/kg), (sulfasalazine 500 mg/kg) or both in combination for 7 consecutive days. Body weight, some hematological parameters, colonic malondialdehyde (MDA) and myeloperoxidase activity (MPO), antioxidant parameters, colon injury and mucosa architectures were assessed. T helper (Th1)-related cytokines [Tumor necrosis factor alpha (TNF-α) and interferon-gamma (INF-γ)], Th2-relarted cytokines (interleukin-4 [IL-4 and IL-10], and Th-17 related cytokines [IL-17] were determined by ELISA. Osthole significantly improved the loss in body weight. That was accompanied with a remarkable amelioration of the disruption of the colonic architecture as well as a significant improvement in the antioxidant defense system. A reduction in MPO and MDA was observed in flamed colon. Treatment with either osthole or combination therapy showed suppressive activities on pro-inflammatory Th2-related cytokines and upregulation of anti-inflammatory Th2-related cytokines The results of this study suggest that osthole exert beneficial therapeutic effect in experimental colitis and improved the efficacy of the synthetized drugs such as sulfasalazine. Therefore, osthole may have a valuable sound in the treatment of inflammatory bowel disease. [ABSTRACT FROM AUTHOR]

Auraptene (AUR) is a bioactive antioxidant coumarin with valuable pharmacological properties; however, poor water solubility is a substantial issue for the topical application of AUR. Therefore, we sought to prepare solid lipid nanoparticles (SLNs) containing AUR (AUR-SLNs) to enhance its anti-inflammatory effect. The prepared formulations were optimized by applying the response surface method. Furthermore, AUR-SLNs were compared to conventional cream containing AUR regarding both the permeation rate of the nanoparticles and the anti-inflammatory effect through both in vitro and in vivo studies. Particle size and entrapment efficiency of the optimized formulation were 140.9 ± 3.55 nm and 84.11% ± 3.30, respectively. Transmission electron microscopy revealed that the nanoparticles were spherical. Differential scanning calorimetry (DSC) analysis demonstrated no drug-lipid incompatibility in the formulation. Fourier transform-infrared spectroscopy (FTIR) spectra revealed the amorphous state of AUR and the encapsulation of this agent in SLNs. The in vitro permeation studies exhibited that AUR-SLNs could significantly enhance cutaneous uptake of AUR and skin targeting. The anti-inflammatory and histopathological studies exhibited no significant differences between AUR-SLNs and indomethacin. AUR-SLNs did not induce skin sensitization in guinea pigs. The results suggest that SLNs could be appropriate carriers for the topical application of AUR as a natural anti-inflammatory agent. [ABSTRACT FROM AUTHOR]

Daphnetin (Daph), a natural coumarin derivative isolated from plants of the Genus Daphne , possesses abundant biological activities, such as anti-inflammatory, antioxidant and anticancer properties. In the present study, we focused on investigating the protective effect of Daph against tert -butyl hydroperoxide ( t -BHP)-induced oxidative damage, mitochondrial dysfunction and the involvement of underlying molecular mechanisms. Our findings indicated that Daph effectively inhibited t -BHP-stimulated cytotoxicity, cell apoptosis, and mitochondrial dysfunction, which are associated with suppressed reactive oxygen species (ROS) generation, decreased malondialdehyde (MDA) formation, increased superoxide dismutase (SOD) levels and glutathione (GSH)/GSSG (oxidized GSH) ratio. Further investigation indicated that Daph significantly suppressed cytochrome c release and NLRP3 inflammasome activation and modulated apoptosis-related protein Bcl-2, Bax, and caspase-3 expression. Moreover, Daph dramatically induced the expression of the glutamate-cysteine ligase modifier (GCLM) subunit and the glutamate-cysteine ligase catalytic (GCLC) subunit, heme oxygenase-1 (HO-1), and NAD (P) H: quinone oxidoreductase (NQO1), which is largely dependent on upregulating the nuclear factor-erythroid 2-related factor 2 (Nrf2) nuclear translocation, reducing the Keap1 protein expression, and strengthening the antioxidant response element (ARE) promoter activity. Additionally, Daph remarkably activated a c-Jun NH2-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK) phosphorylation, but ERK and JNK inhibitor pretreatment exhibited an evident decrease of the level of Daph-enhanced Nrf2 nuclear translocation. Furthermore, Daph exposure suppressed t -BHP-induced cytotoxicity and ROS overproduction, which are mostly blocked in Nrf2 knockout RAW 264.7 cells and peritoneal macrophages. Accordingly, Daph exhibited protective roles against t -BHP-triggered oxidative damage and mitochondrial dysfunction by the upregulation of Nrf2 antioxidant signaling pathways, which may be involved in the activation of JNK and ERK. [ABSTRACT FROM AUTHOR]

In this review, we will present the different aspects of coumarins and derivatives, from natural origins or synthetically prepared, and their action on inflammation. Coumarins and also furo- and pyranocoumarins are found in many different plants. These compounds are very often investigated for antioxidant properties. Other biological properties are also possible and anti-inflammation activity is one of these. As coumarins are also available quite easily via synthesis, natural ones can be prepared this way but derivatives with special substituents are also feasible. A review on the same topic appeared in 2004 and our contribution will take into account everything published since then. [ABSTRACT FROM AUTHOR]

The present study aimed to develop quercetin, resveratrol and genistein loaded self-nanoemulsifying drug delivery system (SNEDDS) by QbD approach in order to improve their oral bioavailability and antioxidant potential. The size and PDI of the optimized formulation were found to be < 200 nm and < 0.3, respectively. DPPH scavenging assay showed comparable antioxidant activity of antioxidant loaded SNEDDS to free antioxidants combination. Furthermore, coumarin-6 loaded SNEDDS formulation showed rapid internalization within 1 h of incubation by Caco-2 cells. Moreover, the pharmacokinetic studies in rats for the optimized formulation and free antioxidant suspension were performed. SNEDDS have significantly increased the C max and area under curve (AUC) of all three antioxidants. The SNEDDS demonstrated ~ 4.27 fold enhancement in oral bioavailability of quercetin, ~ 1.5 fold in case of resveratrol and ~ 2.8 fold in case of genistein as compared to free antioxidants suspension. Finally, the prophylactic antitumor efficacy of developed formulation was tested against DMBA induced breast cancer model in rats, which demonstrated enhanced abeyance towards the tumor growth as compared to free antioxidants. [ABSTRACT FROM AUTHOR]

Banana is an extensively cultivated plant worldwide, mainly for its fruit, while its ancillary product, the banana flower is consumed as a vegetable and is highly recommended for diabetics in the traditional Indian medicine system. This study is based on an investigation of the in vivo antihyperglycaemic activity of Umbelliferone (C1) and Lupeol (C2) isolated from the ethanol extract of banana flower (EF) in alloxan induced diabetic rat model. Diabetic rats which were administered with C1, C2 and EF (100 and 200 mg/kg b. wt.) for 4 weeks showed deterioration in fasting hyperglycaemia and reversal of abnormalities in serum/urine protein, urea and creatinine, when compared to the diabetic control group of rats. The diabetic group of rats fed with EF, C1 and C2 (100 mg/kg b. wt.) once daily, for a period of 28 days resulted in a significant reduction of diabetic symptoms viz., polyphagia, polydipsia, polyuria and urine sugar together with an improved body weight. HbA1c extent was reduced whereas levels of insulin and Hb were increased. Both the extract and compounds wielded positive impacts in diabetic rats by reversal of altered activities of hepatic marker enzymes viz., aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP); glycolytic enzyme (hexokinase); shunt enzyme (glucose-6-phosphate dehydrogenase); gluconeogenic enzymes (glucose-6-phosphatase, fructose-1,6-bisphosphatase, lactate dehydrogenase) and pyruvate kinase. The characteristic diabetic complications such as hypercholesterolemia and hypertriacylglycerolemia also significantly reverted to normal in the serum/liver of diabetic rats. Besides these, the treatment increased the activities of enzymatic and non-enzymatic antioxidants in the serum and liver. The histological observations revealed a marked regeneration of the β-cells in the drug treated diabetic rats. In conclusion, the present study illustrates that EF, C1 and C2 enhances the glycolytic activities, besides increasing the hepatic glucose utilization in diabetic rats by stimulating insulin secretion from the remnant β-cells along with potential enzymatic and non-enzymatic antioxidant activities. [ABSTRACT FROM AUTHOR]

A series of 3-acylhydrazono-4-hydroxycoumarins were synthesized via condensation of 3-acetyl-4-hydroxycoumarinwith appropriate hydrazides. The structures of the newly-synthesized compounds were characterizedby spectral andelememental analysis orHRMSmeasurements. Their antioxidant properties were evaluated by using scavenging effects on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical as well as inhibition of lipid peroxidation. Moreover, their ability to inhibit in vitro soybean lipoxygenase has been investigated. They were found to be capable of rapid inactivation of alkylperoxy radicals. [ABSTRACT FROM AUTHOR]

Syntheses of coumarins, which are a structurally interesting antioxidant activity, was done in this article. The modification of 7-hydroxycoumarin by different reaction steps was done to yield target compounds. Molecular structures were characterized by different spectroscopical techniques (Fourier transformation infrared and nuclear magnetic resonance). Antioxidant activities were performed by using various in vitro spectrophometric assays against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and hydrogen peroxide (H2O2). All compounds exhibited high efficiency as antioxidants compared to ascorbic acid. The highest efficiency scavenging activity was found for compound 3 (91.0 ± 5.0), followed by compounds 2 and 4 (88.0 ± 2.00; and 87.0 ± 3.00). Ascorbic acid C was used as a standard drug with a percentage inhibition of 91.00 ± 1.5. The mechanism of the synthesized compounds as antioxidants was also studied. Hartree-Fock-based quantum chemical studies have been carried out with the basis set to 3-21G, in order to obtain information about the three-dimensional (3D) geometries, electronic structure, molecular modeling, and electronic levels, namely HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital), to understand the antioxidant activity for the synthesized compounds. [ABSTRACT FROM AUTHOR]

Context: Foeniculum vulgare ( F. vulgare) is traditionally used to treat inflammatory diseases. Recently, anti-inflammatory and antioxidant activities of methanol extract of the fruits of F. vulgare were reported. To identify biologically active compounds responsible for the anti-inflammatory activity, we isolated four coumarins, scopoletin, 8-methoxypsoralen, bergapten and imperatorin from the fruits of F. vulgare. Objective: This study assessed the anti-inflammatory and antioxidant effects of coumarins isolated from F. vulgare in lipopolysaccharide (LPS)-stimulated macrophages and 12- O-tetradecanoylphorbol-13-acetate (TPA)-stimulated mice. Materials and methods: RAW 264.7 cells were treated with the coumarins (30 µM) and then stimulated with LPS (100 ng/ml). Ears of ICR mice were treated with TPA (1 µg/ear) once a day. Ten microliters each of the four coumarins (200 μg/ml) were topically applied to the ears for 3 days. Antioxidant activities were examined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis 3-ethylbenzthiazoline-6-sulfonic acid (ABTS) scavenging assays. Results: All the tested coumarins showed excellent antioxidant activities in DPPH and ABTS radical scavenging assays. Among the coumarins, imperatorin had the greatest anti-inflammatory activities as measured by inhibition of the pro-inflammatory cytokines production including interleukin (IL)-6 and tumor necrosis factor (TNF)-α in LPS-stimulated RAW 264.7 cells through blockade of the IκB kinase (IKK)/inhibitor of kappa B (IκB)/nuclear factor-κB (NF-κB) pathway. In vivo experiments showed that imperatorin reduced TPA-induced ear thickness/weight, cutaneous cytokines expression and improved histopathological features. Conclusion: Although four coumarins isolated from the fruits of F. vulgare provide effective anti-inflammatory and antioxidant activities, imperatorin is most potent. [ABSTRACT FROM AUTHOR]

Naturally occurring coumarins, having wide spectrum of activities such as antioxidant, anti-inflammatory, anticancer, MAO-B inhibitory and antimicrobial, are frequently used by the researchers to develop novel synthetic and semisynthetic coumarin based therapeutic agents. Many of these agents are hybrid molecules, which are designed through concept of molecular hybridization and have shown multiple pharmacological activities. This multifunctional attribute of these hybrid compounds makes them potential drug candidates for the treatment of multifactorial diseases such as cancer, Alzheimer's disease, metabolic syndromes, AIDS, malaria, and cardiovascular diseases. The present review compiles research reports on development of different coumarin hybrids, classify these on the basis of their therapeutic uses and propose structure-activity relationships. It is intended to help medicinal chemist in designing and synthesizing novel and potent hybrid compounds for the treatment of different disorders. [ABSTRACT FROM AUTHOR]

The antigenotoxic effects of umbelliferone (UMB), herniarin (HER) and 7-isopentenyloxy coumarin (7-IP), common natural dietary coumarins, were evaluated on the human lymphocyte DNA damage using single-cell gel electrophoresis. H2O2-induced DNA break was measured based on the percentage of DNA in tail, and the antigenotoxic effects of the tested compounds were compared with that of ascorbic acid (10, 25, 50, 100 and 200 μM). UMB, HER and 7-IP did not show any genotoxicity, as compared to phosphate-buffered saline. Treatment with UMB, HER and 7-IP led to a significant reduction in the percentage of DNA in tail induced by H2O2 ( p < 0.001) at all concentrations. The presence of prenyl moiety in the chemical structure of 7-IP may contribute to its better antigenotoxic property, compared to UMB. The results of this study showed that 7-IP possessed the best antigenotoxic activity among the tested compounds. [ABSTRACT FROM AUTHOR]

Abstract: Coumarins comprise a broad class of phenolic compounds that influences the formation and scavenging of reactive oxygen species and the processes involving free radical-mediated injury. In light of the antioxidant and anti-inflammatory properties of esculetin and 4-methylesculetin, the aim of this study was to investigate the effects of these compounds in an experimental model of rat colitis induced by trinitrobenzenesulphonic acid (TNBS). For this purpose, macroscopic (diarrhoea, extension of lesion, colonic weight/length ratio and damage score) and biochemical parameters (myeloperoxidase, alkaline phosphatase and glutathione) were evaluated. Our results reveal that these compounds, particularly 4-methylesculetin, may be effective for the treatment of intestinal inflammatory bowel disease. In the acute colitis model, esculetin promoted a reduction in the extension of the lesion accompanied by a reduction in the incidence of diarrhoea and restoration of the glutathione content. Similar effects were produced by the administration of 4-methylesculetin, which also inhibited the myeloperoxidase and alkaline phosphatase activities in the acute intestinal inflammatory process and in the model of colitis relapse. The effect of the esculetin and 4-methylesculetin on the inflammatory process may be related to their antioxidant and anti-inflammatory properties, as observed in this study. The evidence for better effects of 4-methylesculetin in comparison to those demonstrated by esculetin in both experimental settings could be attributed to the presence of the methyl group at C-4 of 4-methylesculetin. [Copyright &y& Elsevier]

Abstract: A facile, convenient and high yielding synthesis of a combinatorial library of 3-alkanoyl/aroyl/heteroaroyl-2H-chromene-2-thiones has been developed by the condensation of easily accessible β-oxodithioesters and salicylaldehyde/substituted 2-hydroxybenzaldehydes under solvent-free conditions. The assessment of radical scavenging capacity of the compounds towards the stable free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) was measured and these compounds were found to scavenge DPPH free radical efficiently. Five selected compounds were able to protect curcumin from the attack of sulfur free radical generated by radiolysis of glutathione (GSH). The newly synthesized compounds exhibited profound antioxidant activities. Five of them rendered comparatively high antioxidant capacity. [Copyright &y& Elsevier]

Abstract: A series of novel benzocoumarin derivatives were synthesized and evaluated for their in vivo anti-dyslipidemic and in vitro antioxidant activities. Preliminary screening indicates compound 4 as potential lead with significant lipid lowering and antioxidant activities. The study revealed that such attempts on benzocoumarin-based pharmacophores which is a biologically important scaffold might result in identification of new lead for anti-dyslipidemia. [Copyright &y& Elsevier]

Abstract: Different substituted 3,3′-arylidenebis-4-hydroxycoumarins (1–7) and tetrakis-4-hydroxycoumarin derivative 8 are the final products when 4-hydroxycoumarin and aromatic aldehydes containing different groups in ortho, meta or para positions condense in boiling ethanol or acetic acid. Upon heating 3,3′-arylidenebis-4-hydroxycoumarins, and tetrakis-4-hydroxycoumarin derivative in anhydride acetic acid, the epoxydicoumarins (9–16) were formed. From a study of nuclear magnetic resonance and infrared spectra, intramolecularly hydrogen-bonded structures are proposed for the dicoumarols (1–8). A possible relationship between such hydrogen-bonded structures and the antimicrobial and the antioxidant activities of compounds 1–8 is suggested. [Copyright &y& Elsevier]