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In ischemic stroke, reperfusion after thrombolysis is associated with secondary brain damage. Dihydromyricetin (DHM), a flavonoid, has shown neuroprotective effects through anti-oxidant, anti-inflammatory and anti-apoptotic properties. This study investigates the potential of DHM, given postreperfusion in middle cerebral artery occlusion (MCAo) model of stroke in rats. MCAo surgery was performed in male Wistar rats. Reperfusion was performed after 90 min of ischemia. DHM (50 and 100 mg/kg) was administered 10–15 min and 2 h postreperfusion followed by daily dosing for 2 more days. Neurobehavioral parameters and infarct size (TTC staining) were assessed after 72 h. The effective dose (100 mg/kg) was then used to study reduction in infarct size (measured by MRI) and effect on apoptosis (evaluated by protein expression of Bax, Bcl-2 and cleaved caspase-3 and TUNEL assay) in peri-infarct cortex. Furthermore, effects of DHM on neuronal damage and activation of astrocytes were studied by immunofluorescence. Poststroke DHM (100 mg/kg) administered for 3 days showed significant improvements in motor-coordination and infarct damage (TTC staining and MRI). MCAo-induced altered apoptotic proteins were normalized to a significant extent in peri-infarct cortex with DHM treatment. Data from TUNEL assay were complementary to the effects on apoptotic proteins. Additionally, DHM caused a significant reduction in the number of reactive astrocytes when compared with the MCAo group. This study demonstrated the efficacy of subacute DHM treatment in ischemia/reperfusion injury by modulating apoptosis and astrogliosis in the peri-infarct cortex. This suggests the potential of DHM in attenuating disease progression. [ABSTRACT FROM AUTHOR]

• Two flavonoids and one ellagic acid derivative were isolated from the roots of Euphorbia tirucalli. • 13 compounds were identified by HPLC-MS/MS analysis. • Ethanol extract from roots of E. tirucalli and the isolated compounds displayed significant antimicrobial activity. Euphorbia tirucalli (Euphorbiaceae) is a species widely utilized for popular medicine in northeast of Brazil because of its innumerable reported medicinal properties. The HPLC-Qtrap-MS/MS analysis from E. tirucalli roots ethanol extract revealed that this species presents 8 flavonoids and 5 shikimate derivative compounds. Chemical studies of these ethanolic extract using chromatographic procedures allowed the isolation of four previously unreported compounds for this species: myricetin, 3,3'-dimethoxy-4- O -α-rhamnopyranoside-ellagic acid, 4- O -methyl-gallic acid and ampelopsin. All structures were determined using 1D and 2D NMR spectroscopy analysis. The ethanol extract and four isolated compounds were evaluated for antimicrobial activity against Staphylococcus aureus , Escherichia coli , Sporothrix brasiliensis and Candida albicans. All the analyzed compounds presented activity against all evaluated bacteria and fungi, with MIC values ranging from 8 to 2048 μg/mL. [ABSTRACT FROM AUTHOR]

Ampelopsin (APS) is the main bioactive component from Ampelopsis grossedentata and has anti-inflammatory properties. We hypothesize that it could reduce the acute phase response (APR) and help to maintain balance between inflammation-mediated oxidative damage and APS-induced protective mechanisms in liver. In the present study, APS possessed strong DPPH, ABTS, H 2 O 2 and O 2 radical scavenging activities in different in vitro antioxidant assays. Further study demonstrated that APS alleviated APR as reflected in the changes in the whole body metabolic rate, physical conditions, and production of cytokines in LPS-treated piglets. Moreover, APS has the potential to prevent Akt-mediated activation of NF-κB and decreased the levels of STAT3 in inflammation. The administration of APS ameliorated mitochondrial dysfunction and moderated the involvement of Ref-1 and Nrf2 in the attenuation in LPS-induced APR. The present results suggest that the APS attenuate LPS induced inflammation and oxidative stress in liver of piglets. [ABSTRACT FROM AUTHOR]

Increasing evidence has demonstrated that oxidative stress is involved in the pathogenesis of Parkinson's disease (PD), suggesting that pharmacological targeting of the antioxidant machinery may have therapeutic potential. Ampelopsin, a natural flavonoid compound, has been reported to possess various pharmacological functions, including anti-inflammatory, anti-oxidative and anti-cancer effects. However, its neuroprotective effect and neurotoxicity-attenuating role as well as underlying mechanisms are still unclear. In the present study, we investigated the potential role of ampelopsin in neuroprotective function and neurotoxicity attenuation, and explored its corresponding mechanisms against 6-hydroxydopamine (6-OHDA)-induced neurotoxicity in the cell model of PD. The pretreatment with ampelopsin for 1 h significantly improved cell viability, reduced the release of lactate dehydrogenase (LDH) and inhibited the accumulation of reactive oxygen species (ROS) in 6-OHDA-stimulated PC12 cells. In addition, ampelopsin treatment attenuated 6-OHDA-induced apoptosis of PC12 cells by inhibiting the phosphorylation of p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK). Moreover, ampelopsin treatment significantly increased the localization of nuclear factor-erythroid 2-related factor 2 (Nrf2) and subsequent activation of haem oxygenase-1 (HO-1) gene associated with antioxidant response element (ARE) pathway in a dose-dependent manner. Further study demonstrated that ampelopsin treatment suppressed the expression of glycogen synthase kinase-3β (GSK-3β). The present results suggest that the neuroprotective role of ampelopsin is due to the increased expression of Nrf2 through suppressing GSK-3β signalling, thereby correspondingly inhibiting ROS/p-p38/p-JNK MAPK signalling pathway. Therefore, ampelopsin has promising therapeutic potential for PD. [ABSTRACT FROM AUTHOR]

• Vine tea and dihydromyricetin (DHM) can improve shelf life and quality of foods. • Vine tea extracts and DHM prevented oxidation better than synthetic antioxidants. • Solubility and stability can limit application of vine tea extract and DHM in foods. Herbal teas like vine tea (Ampelopsis grossedentata) have been traditionally consumed worldwide because of their health-promotion and pleasant taste. Vine tea and its main bioactive component, dihydromyricetin, have gained attention because of their potential applications in food, material, and pharmaceutical sciences. Vine tea and dihydromyricetin have been suggested as potential natural antioxidants to extend shelf life of foods. Studies have also suggested potential application in packaging and food safety. Additionally, dietary supplementation with vine tea extract have shown great potential to prevent metabolic diseases, which can justify its application in novel functional foods. This review discusses the chemistry, functional properties, and potential applications of vine tea and dihydromyricetin in the food industry. Although vine tea extracts and dihydromyricetin have shown promising results, further studies on optimal application, thermal stability, synergetic effect with other natural antioxidants, consumer acceptability, and sensory profile of vine tea are needed to support food product innovation. [ABSTRACT FROM AUTHOR]