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Excessive reactive oxygen species (ROS) generated during cerebral ischemic reperfusion (CIRI) are crucial for subsequent tissue damage. However, despite the potential benefits of antioxidants reported in clinical applications, few have proven effective in treating CIRI, particularly in the elderly. Epicatechin (EC) is a catechol flavonoid monomer derived from natural tea plants. Multiple phenolic hydroxyl groups give it strong antioxidant properties, which can not only degrade ROS through chemical reactions between hydroxyl and ROS but also enhance the activity of antioxidant enzymes in cells, and it is easy to penetrate the blood–brain barrier. But its antagonistic effect on age‐related CIRI and potential medicinal value are still unknown. Nuclear factor erythroid 2‐related factor 2 (Nrf2) is the most important transcription factor regulating the expression of antioxidant proteins in the body. This study first compared the pathological differences of the Nrf2 system in CIRI between 2‐month‐old and 12‐month‐old Sprague–Dawley (SD) rats. Subsequently, EC was administered to 12‐month‐old rat models of middle cerebral artery occlusion and reperfusion (MCAO/R) and senescent SH‐SY5Y cell models subjected to oxygen glucose deprivation/reoxygenation (OGD/R). EC treatment improved cerebral morphology and function; increased p‐Nrf2, heme oxygenase‐1 (HO‐1), superoxide dismutase (SOD), and glutathione (GSH) expression; reduced infarct volume; and neuronal apoptosis in senescent rats. Moreover, EC enhanced cellular activity and the expression of p‐Nrf2, HO‐1, and quinone oxidoreductase‐1 (NQO‐1) while decreasing ROS and malondialdehyde (MDA) levels and mitigating apoptosis in senescent SH‐SY5Y cells. These effects were reversed upon si‐Nrf2. In sum, we confirm that EC exerts neuroprotective effects by upregulating Nrf2/ARE and reducing oxidative stress, suggesting that EC may be a promising drug for the treatment of senile cerebral apoplexy. This study also provides a scientific basis for the development and selection of new drugs for ischemic stroke in elderly patients. [ABSTRACT FROM AUTHOR]

This letter proposes an augmented scheme of LT codes to improve the decoding success rate. The method involves substituting the 1‐s in full‐degree columns of the generator matrix of conventional LT codes with binary extension field elements and simultaneously increasing the ratio of full‐degree columns in the ideal soliton distribution. For non‐full‐degree columns, we retain the nonzero elements as 1‐s in the conventional LT codes generator matrix to preserve computational efficiency. Compared to conventional LT codes, the proposed method enhances the linear independence of the generator matrix, leading to a higher decoding success rate with minimal data packets. Experimental results demonstrate the effectiveness of the method at improving the performance of LT codes, with close to 100% decoding success rate achieved with around 5% data redundancy. [ABSTRACT FROM AUTHOR]

Resveratrol is notable not only for its functions in disease resistance in plants but also for its health benefits when it forms part of the human diet. Identification of new transcription factors helps to reveal the regulatory mechanisms of stilbene synthesis. Here, the WRKY53 transcription factor was isolated from the Chinese wild grape, Vitis quinquangularis. Vqwrky53 was expressed in a variety of tissues and responded to powdery mildew infection and to exogenous hormone application. VqWRKY53 was located in the nucleus and had transcriptional activation activity in yeast. A yeast two-hybrid assay and a bimolecular fluorescence complementation assay confirmed that VqWRKY53 interacted physically with VqMYB14 and VqMYB15, which have previously been reported to regulate stilbene synthesis. When Vqwrky53 was overexpressed in grape leaves, the expression of VqSTS32 and VqSTS41 and the content of stilbenes were increased. A yeast one-hybrid assay demonstrated that VqWRKY53 could bind directly to the promoters of STS genes. Overexpression of Vqwrky53 activated β-glucuronidase expression, driven by STS promoters, and co-expressing Vqwrky53 with VqMYB14 and VqMYB15 showed stronger regulatory functions. Heterologous overexpression of Vqwrky53 in Arabidopsis accelerated leaf senescence and disease resistance to Pst DC3000. [ABSTRACT FROM AUTHOR]

• Resveratrol offers both the resistance to fungal and benefits in human health as a cardioprotective, antitumor and neuroprotective agent. • VqbZIP1 isolated from Chinese wild Vitis quinquangularis was functionally characterized. • The yeast two-hybrid assay and BiFC assay together show that VqbZIP1 interacts with VqSnRK2.4 and VqSnRK2.6. • Overexpression of VqbZIP1 in grape leaves can activate the expression of the STS genes and stilbene accumulation. • Overexpression of VqbZIP1 in Arabidopsis thaliana increased ABA sensitivity of plants. Resveratrol is an important phytoalexin in grapevine. Not only does it confer increased disease resistance and but as a food component it offers significant benefits in human health. Abscisic acid (ABA) is an important phytohormone involved in many biological processes in plants and can also promote the accumulation of stilbenes. Stilbene synthase (STS) is an important enzyme which catalyzes the last step of resveratrol synthesis. Our study characterizes a basic leucine zipper (bZIP) transcription factor, VqbZIP1 , isolated from Chinese wild Vitis quinquangularis accession Danfeng-2. The results show that VqbZIP1 encodes 299 amino acids and belongs to the Group A subfamily of the bZIP family. VqbZIP1 showed transcriptional activation activity in yeast and is predicted to be located in the nucleus. The yeast two-hybrid assay and bimolecular fluorescence complementation (BiFC) assay together show that VqbZIP1 interacts with VqSnRK2.4 and VqSnRK2.6. VqbZIP1 , the STS genes, VqSnRK2.4 and VqSnRK2.6 can all be induced by ABA treatment. A GUS activity experiment indicates VqbZIP1 can activate the GUS reporter gene driven by STS promoters. Further studies show that co-expression of VqbZIP1 with VqSnRK2.4 or VqSnRK2.6 can confer higher efficiency than expression of VqbZIP1 alone in activating the STS promoters. Overexpression of VqbZIP1 in grape leaves promoted the transcript level of the STS genes and the accumulation of stilbenes. Overexpression of VqbZIP1 in Arabidopsis thaliana can confer ABA sensitivity. In summary, our results suggest VqbZIP1 participates in the ABA signaling pathway and regulates stilbene synthesis. [ABSTRACT FROM AUTHOR]

An F-box protein (VpEIFP1) induced by Erysiphe necator was isolated from Vitis pseudoreticulata , a wild Chinese grapevine species naturally resistant to powdery mildew (PM). It contains an F-box domain and two Kelch-repeat motifs. Expression profiles indicate the VpEIFP1 is strongly induced at both transcriptional and translational levels by PM infection. A subcellular localisation assay showed that VpEIFP1 is predominantly located in the nucleus and cytoplasm. Overexpression of VpEIFP1 accelerated the accumulation of hydrogen peroxide (H 2 O 2 ) and up-regulated the expressions of ICS2 , NPR1 and PR1 involved in defence responses, resulting in suppression of PM germination and growth. As an F-box protein, VpEIFP1 interacts with thioredoxin z (VpTrxz) in the yeast-two-hybrid (Y2H) assay and in the bimolecular fluorescence complementation (BiFC) assay. Decreased amounts of VpTrxz protein in transgenic grapevine leaves overexpressing VpEIFP1 were restored by proteasome inhibitor MG132, implying that VpEIFP1 mediated VpTrxz for degradation through the SCF VpEIFP1 (Skp1-Cullin-F-box) E3 ubiquitin ligase complex. The RNA interference line of VpTrxz showed increased H 2 O 2 accumulation following PM inoculation. We propose VpEIFP1 positively modulates the grapevine defence response to PM by inducing the degradation of VpTrxz via the ubiquitin/26S proteasome system. [ABSTRACT FROM AUTHOR]