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Alzheimer's disease (AD) is a major cause of dementia in the elderly with no effective treatment. Accumulation of amyloid-β peptide (Aβ) in the brain, one of the pathological features of AD, is considered to be a central disease-causing and disease-promoting event in AD. In this study, we showed that feeding male AβPP/PS1 transgenic mice, a well established mouse model of AD, with a diet containing phenolic antioxidant tert-butylhydroquinone (TBHQ) dramatically reduced brain Aβ load with no significant effect on the amounts of alpha- and beta-C-terminal fragments or full-length AβPP. Further studies showed that TBHQ diet inhibited the expression of plasminogen activator inhibitor-1 (PAI-1), a protease inhibitor which plays a critical role in brain Aβ accumulation in AD, accompanied by increases in the activities of tissue type and urokinase type plasminogen activators (tPA and uPA) as well as plasmin. Moreover, we showed that TBHQ diet increased the expression of low density lipoprotein related protein-1, a multi ligand endocytotic receptor involved in transporting Aβ out of the brain, and plasma Aβ(40) and Aβ(42) levels. We also showed that TBHQ diet increased the concentration of glutathione, an important antioxidant, and suppressed the expression of NADPH oxidase 2 as well as lipid peroxidation. Collectively, our data suggest that TBHQ may have therapeutic potential for AD by increasing brain antioxidant capacity/reducing oxidative stress level and by stimulating Aβ degradation/clearance pathways. [ABSTRACT FROM AUTHOR]

Abstract: Cornu Bubali (water buffalo horn, WBH) has been used in Traditional Chinese Medicine (TCM) for thousands of years. In the present study, three peptides with antioxidant properties were purified from aqueous extract of Cornu Bubali (water buffalo horn, WBH) by consecutive chromatographic methods including gel filtration chromatography, ion-exchange chromatography and high performance liquid chromatography. The sequences of the three peptides were identified to be Gln-Tyr-Asp-Gln-Gly-Val (WBH-1, 708Da), Tyr-Glu-Asp-Cys-Thr-Asp-Cys-Gly-Asn (WBH-2, 1018Da) and Ala-Ala-Asp-Asn-Ala-Asn-Glu-Leu-Phe-Pro-Pro-Asn (WBH-3, 1271Da) by matrix assisted laser desorption ionization time-of-flight/time-of-flight mass spectrometry (MALDI-LIFT-TOF/TOF MS). The antioxidant activity of these peptides was tested using 1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assay directly. Methylthiazol tetrazolium (MTT) assay and lactate dehydrogenase (LDH) release assay were also used to evaluate the protection of peptides against hydrogen peroxide (H2O2) induced injury. The results showed that these peptides could reduce the DPPH radical and protect rat cerebral microvascular endothelial cells (rCMECs) against H2O2-induced injury, thus demonstrating that these peptides had antioxidant activity. These results suggest that WBH-1, WBH-2 and WBH-3, isolated from the aqueous extract of water buffalo horn are natural antioxidants and may contribute to the efficacy of WBH. [Copyright &y& Elsevier]

Cornu Bubali (water buffalo horn, WBH) is an animal-derived product which is widely used in Traditional Chinese Medicine (TCM) for dispelling heat, relieving convulsions and cooling blood. The purpose of this study was to investigate the antipyretic activity of WBH aqueous extract and its potential mechanism. Two hyperthermia models, yeast-induced (infectious) and skimmed milk-induced (noninfectious) hyperthermia were employed to evaluate the antipyretic effect and the results showed that rectal temperature of hyperthermia animals was decreased significantly after oral administration of WBH extract. The production of tumor necrosis factor-α (TNF-α)-induced prostaglandin E2 (PGE2) in rat cerebral microvascular endothelial cells (rCMECs) was inhibited by WBH extract in the concentrations of 10 μg/ml and 100 μg/ml. The WBH extract protected rCMECs survival from hydrogen peroxide (H2O2)-induced toxicity and inhibited the H2O2-induced leakage of lactate dehydrogenase (LDH) enzyme release at a dose ranging from 5 μg/ml to 100 μg/ml. It could also increase the superoxide dismutase (SOD) and catalase (CAT) enzyme activities. The results suggest that Cornu Bubali exhibits antipyretic activity on both infectious and noninfectious hyperthermia. The antipyretic activity of WBH may be due to the effects on enhancing antioxidation enzyme activities, decreasing PGE2 production, and protecting the rCMECs against H2O2-induced injury. [ABSTRACT FROM AUTHOR]

Abstract: A sensitive and specific reversed-phase high-performance liquid chromatography with ultraviolet detection (RP-UV-HPLC) method has been developed and validated for the identification and quantification of pinocembrin in rat plasma using chrysin as the internal standard. Following protein precipitation with acetonitrile, the analytes were separated by the mobile phase 0.01M ammonium acetate (pH 4.0)–methanol (35:65, v/v) with an Agilent TC-C18 column (5μm, 4.6mm×150mm) at a flow rate of 1ml/min, column temperature 40°C and detection wavelength 290nm. A good linear relationship was obtained in the concentration range studied (0.07–133.33μg/ml, r =0.9995). The lowest limit of quantification (LLOQ) was 66.7ng/ml and the lowest limit of detection (LLOD) was 25ng/ml. Average recoveries ranged from 93.9 to 97.8% in plasma at the concentrations of 0.33 and 33.33μg/ml. Intra- and inter-batch relative standard deviations were 0.15–2.03 and 1.18–9.96%, respectively. This method was successfully applied to the pharmacokinetic studies in rats after intravenous administration of pinocembrin. [Copyright &y& Elsevier]

Alcoholic liver disease (ALD) is one of the leading causes of death in the world. Oxidative stress plays an important role in the pathogenesis of alcohol-induced liver injury. Our previous results have found that oleanolic acid (OA), a liver protective agent, plays a potent antioxidant activity in hepatocyte. In the present study, the protective effects of OA co-administration on ethanol-induced oxidative injury in rats were investigated through detecting hepatic histopathology, antioxidant enzymes, ethanol metabolic enzymes and inflammatory factors. Preventions of ethanol-induced oxidative injury by OA were reflected by markedly decreased serum activities of AST, ALT and significantly increased the hepatic ATP level. In addition, the increase of the hepatic TG content, MDA level and the decrease of hepatic GSH level, SOD activity, CAT activity induced by ethanol were significantly inhibited by OA co-administration. Furthermore, OA could also elevate the protein expressions and nuclear translocation of antioxidant transcription factor Nrf-2 and then up-regulated antioxidant enzymes expressions of HO-1, SOD-1 and GR. Moreover, OA co-administration can significantly reduce the activity and expressions of CYP2E1 and ADH, which has characteristic of generation ROS mediated oxidative stress and acetaldehyde respectively. Furthermore, OA co-administration could inhibition of the generation of inflammatory factors TNF-α and IL-6. Those above results indicated that OA co-administration can protect rats against ethanol-induced liver injury by induction Nrf-2 related antioxidant to maintain redox balance and modulating the ethanol-metabolizing and inflammatory pathway. [ABSTRACT FROM AUTHOR]

Consumption of brown rice is associated with reduced risk of chronic diseases, which might be attributed to the presence of unique phytochemicals. This study aimed to evaluate phytochemicals profile, cellular antioxidant and anti-proliferative activities in glutinous and non-glutinous brown rice varieties of indica and japonica subspecies. In general, bound fractions of brown rice depicted significant variation levels of phytochemicals, antioxidant and anti-proliferative activities. Anti-proliferative activity of bound fraction, total antioxidant capacity and cellular antioxidant activity of non-glutinous type were significantly higher than glutinous type ( p  < 0.05). Present investigation could be significant to introduce brown rice as functional foods and to increase awareness about health benefits of whole grain. [ABSTRACT FROM AUTHOR]

Phytochemical profiles, antioxidant and antiproliferative activities of berry extracts were evaluated and compared in four subspecies of Sea buckthorn ( Hippophaë rhamnoides L.). Among the subspecies, Hippophaë rhamnoides L. subsp. sinensis exhibited highest total phenolics content (38.7 ± 1.3 mg GA equiv./g DW) and corresponding total antioxidant activity. Whereas maximum cellular antioxidant and antiproliferative activities were determined in Hippophaë rhamnoides L. subsp . yunnanensis . Total antioxidant activity was significantly associated to total phenolics, isorhamnetin-3-rutinoside and isorhamnetin-3-glucoside. The cellular antioxidant activity and antiproliferative activity of phytochemicals were fairly correlated to phenolic acids and flavonoid aglycones. Lower median effective dose (EC 50 ) of individual compounds against human liver cancer HepG2 cells proliferation studies confirmed the better correlation between antiproliferative activity of Sea buckthorn extracts and flavonoid aglycones, including isorhamnetin, quercetin and kaempferol. [ABSTRACT FROM AUTHOR]

Single-factor experiment and Box–Behnken design (BBD) were applied to optimize the ultrasound-assisted extraction of mulberry fruits polysaccharides (MFP). Under optimum conditions: ratio of water to raw material 40.25, extraction temperature 69 °C, ultrasonic power 190 W and extraction time 75 min, the MFP yield was 3.13% (±0.07%), in accordance to the predicted value of 3.04%. The mulberry fruits polysaccharides fractions was obtained by deproteinization (MFP-1), followed by decolorization and deionization (MFP-2). Carbohydrate content in MFP, MFP-1 and MFP-2 was 58.61% (±1.47%), 69.98% (±0.91%), 81.18% (±1.29%), as well as proteins was estimated 16.50% (±0.86%), 1.57% (±0.63%), 1.02% (±0.18%), respectively. The FT-IR indicated that MFP, MFP-1 and MFP-2 were acidic polysaccharides. The MFP-1 exhibited the strongest antioxidant activity, while MFP-2 showed the strongest hyperglycemic activity in vitro . This may be caused by their different compositions and physical properties in the different mulberry fruit polysaccharides fractions. [ABSTRACT FROM AUTHOR]