TREM2, a critical activator of pyroptosis, mediates the anti­tumor effects of piceatannol in uveal melanoma cells via caspase 3/GSDME pathway

Uveal melanoma (UM) is the most prevalent type of primary intraocular malignancy and is prone to metastasize, particularly to the liver. However, due to the poor understanding of the pathogenesis of UM, effective therapeutic approaches are lacking. As a phenolic compound extracted from grapes, piceatannol (PIC) exhibits anti­cancer properties. To the best of our knowledge, however, the effects of PIC on UM have not been well investigated. Therefore, in the present study, considering the impact of pyroptosis on modulating cell viability, the mechanism underlying the effects of PIC on UM cell proliferation was explored. The inhibitory effect of PIC on proliferation of UM cells was detected by cell counting kit­8 assay. Wound healing was used to investigate the effects of PIC on the migration of UM cells. Activity detecting assays were performed to test the apoptosis and oxidant level in UM cells. Western blotting and RT­qPCR were used to detect the inflammatory and pyroptotic levels of UM cell after PIC treatment. PIC­treated UM cells were screened by high­throughput sequencing to detect the differential expression of RNA and differential genes. Si­TREM2 transfection was used to verify the important role of TREM2 in the effects of PIC. Immunohistochemical staining was used to observe the expressions of TREM2 and GSDMR of tumor in nude mice after PIC administration. PIC effectively inhibited proliferation ability of C918 and Mum­2b UM cell lines via enhancing apoptosis, as evidenced by enhanced activities of caspase 3 and caspase 9. In addition, treatment of UM cells with PIC attenuated cell migration in a dose­dependent manner. PIC increased reactive oxygen species levels and suppressed the activity of the antioxidant enzymes superoxide dismutase, glutathione­S­transferase, glutathione peroxidase and catalase. PIC inhibited inflammatory responses in C918 cells. PIC treatment upregulated IL­1ß, IL­18 and Nod­like receptor protein 3 and downregulated gasdermin D (GSDMD). RNA sequencing results revealed the activation of an unconventional pyroptosis­associated signaling pathway, namely caspase 3/GSDME signaling, following PIC treatment, which was mediated by triggering receptor expressed on myeloid cells 2 (TREM2) upregulation. As an agonist of TREM2, COG1410­mediated TREM2 upregulation inhibited proliferation of C918 cells, displaying similar effects to PIC. Furthermore, PIC inhibited tumor growth via regulating the TREM2/caspase 3/GSDME pathway in a mouse model. Collectively, the present study revealed a novel mechanism underlying the inhibitory effects of PIC on UM, providing a potential treatment approach for UM in clinic.

Pterostilbene-loaded PLGA nanoparticles alter phenylpropanoid and oxylipin metabolism in Solanum lycopersicum L. leaves.

Due to the fast-changing global climate, conventional agricultural systems have to deal with more unpredictable and harsh environmental conditions leading to compromise food production. The application of phytonanotechnology can ensure safer and more sustainable crop production, allowing the target-specific delivery of bioactive molecules with great and partially explored positive effects for agriculture, such as an increase in crop production and plant pathogen reduction. In this study, the effect of free pterostilbene (PTB) and poly(lactic-co-glycolic) acid (PLGA) nanoparticles (NPs) loaded with pterostilbene was investigated on Solanum lycopersicum L. metabolism. An untargeted NMR-based metabolomics approach was used to examine primary and secondary metabolism whereas a targeted HPLC-MS/MS-based approach was used to explore the impact on defense response subjected to anti-oxidant effect of PTB, such as free fatty acids, oxylipins and them impact on hormone biosynthesis, in particular salicylic and jasmonic acid. In tomato leaves after treatment with PTB and PLGA NPs loaded with PTB (NPs + PTB), both NPs + PTB and free PTB treatments increased GABA levels in tomato leaves. In addition, a decrease of quercetin-3-glucoside associated with the increase in caffeic acid was observed suggesting a shift in secondary metabolism towards the biosynthesis of phenylpropanoids and other phenolic compounds. An increase of behenic acid (C22:0) and a remodulation of oxylipin metabolism deriving from the linoleic acid (i.e. 9-HpODE, 13-HpODE and 9-oxo-ODE) and linolenic acid (9-HOTrE and 9-oxoOTrE) after treatment with PLGA NPs and PLGA NPs + PTB were also found as a part of mechanisms of plant redox modulation. To the best of our knowledge, this is the first study showing the role of PLGA nanoparticles loaded with pterostilbene in modulating leaf metabolome and physiology in terms of secondary metabolites, fatty acids, oxylipins and hormones. In perspective, PLGA NPs loaded with PTB could be used to reshape the metabolic profile to allow plant to react more quickly to stresses.

Notch signaling mediated repressive effects of resveratrol in inducing caspasedependent apoptosis in MCF-7 breast cancer cells.

Resveratrol, a potent anticancer bioactive compound, has been shown to trigger apoptosis in numerous cancer cells. Although Notch signaling promotes breast cancer apoptosis, it is unclear whether resveratrol induces apoptosis in MCF-7 cells via influencing the Notch pathway. This study aimed to evaluate the effect of resveratrol on modulating Notch signaling targets and provide critical information for employing resveratrol in breast cancer therapy. Thus, in this study, we have deciphered the effect of resveratrol against three potent genes (Notch1, Jagged1, and DLL4) of the notch signaling pathway. For mechanistic studies, in silico, and in vitro analysis was executed to investigate the apoptotic-inducing potential of resveratrol against three selected oncogenes involved in the progression of breast cancer. Docking analysis revealed the inhibitory potential of resveratrol against all three selected targets of the Notch pathway (Notch1: -5.0; Jagged-1: -5.9; DLL4: -5.8). In vitro, findings further displayed a significant reduction in cell viability in resveratrol-treated MCF-7 cancer cells, which were concomitantly related to the downregulation of Notch-1, Jagged-1, and DLL4. Moreover, the antiproliferative efficacy of resveratrol was correlated with apoptosis and modulation in the expression of Bax, Bcl-2, cyclin D1, CDK4, p21, and caspase-3 activation. Taken together, these experimental findings suggested that apoptotic inducing potential of resveratrol was mediated through a novel mechanism involving suppression of the Notch signaling pathway.

Resveratrol as a cardioprotective adjuvant for 5-fluorouracil in the treatment of gastric cancer cells.

The clinical application of 5-fluorouracil (5-Fu), a potent chemotherapeutic agent, is often hindered by its well-documented cardiotoxic effects. Nevertheless, natural polyphenolic compounds like resveratrol (RES), known for their dual anti-tumor and cardioprotective properties, are potential adjunct therapeutic agents. In this investigation, we examined the combined utilization of RES and 5-Fu for the inhibition of gastric cancer using both in vitro and in vivo models, as well as their combined impact on cardiac cytotoxicity. Our study revealed that the co-administration of RES and 5-Fu effectively suppressed MFC cell viability, migration, and invasion, while also reducing tumor weight and volume. Mechanistically, the combined treatment prompted p53-mediated apoptosis and autophagy, leading to a considerable anti-tumor effect. Notably, RES mitigated the heightened oxidative stress induced by 5-Fu in cardiomyocytes, suppressed p53 and Bax expression, and elevated Bcl-2 levels. This favorable influence enhanced primary cardiomyocyte viability, decreased apoptosis and autophagy, and mitigated 5-Fu-induced cardiotoxicity. In summary, our findings suggested that RES holds promise as an adjunct therapy to enhance the efficacy of gastric cancer treatment in combination with 5-Fu, while simultaneously mitigating cardiotoxicity.

Photoisomerization pathways of trans-resveratrol.

Resveratrol is well-known for promoting health benefits due to its antioxidant, anti-aging, anti-carcinogenic, and other beneficial activities. Understanding the photophysics of resveratrol is essential for determining its applicability to pharmaceutical innovations. In the present work, we used an explore-then-assess strategy to map the internal conversion pathways of trans-resveratrol. This strategy consists of exploring the multidimensional configurational space with nonadiabatic dynamics simulations based on a semiempirical multireference method, followed by a feasibility assessment of reduced-dimensionality pathways at a high ab initio theoretical level. The exploration step revealed that internal conversion to the ground state may occur near five distinct conical intersections. The assessment step showed that the main photoisomerization pathway involves a twisted-pyramidalized S1/S0 conical intersection, yielding either trans or cis isomers. However, a secondary path was identified, where cis-trans isomerization happens in the excited state and internal conversion occurs at a cyclic conical intersection, yielding a closed-ring resveratrol derivative. This derivative, which can be formed through this direct path or an indirect photoexcitation, may be connected to the production of oxygen-reactive species previously reported and have implications in photodynamic therapy.

Efficacy of Stilbene Derivatives in Sensitizing Breast Cancer Cells to Ionizing Radiation.

BACKGROUND/AIMS: One of the treatments for breast cancer is surgical resection of the tumour and prevention of recurrence with postoperative radiotherapy. Unfortunately, radiotherapy is not always effective enough due to the low sensitivity of cancer cells to ionising radiation. This study aimed to evaluate the radiosensitising properties of resveratrol, piceatannol and polydatin on breast cancer cells, which differ in the presence of hormonal receptors on their surface. METHODS: The experimental part was carried out on triple-negative breast cancer cells (HCC38) and hormone-dependent cells (MCF7). The study assessed the level of cell death, changes in the expression of genes (BAX, BCL-2) and proteins related to the apoptosis process (CASPASE 3, 8 and P53), changes in the expression of antioxidant enzymes (CATALASE, SOD, GPx1/2) and NRF-2. Additionally, the expression level of RAD51 protein and histone H2AX, which are involved in DNA repair processes, was assessed. Statistical significance was evaluated by a two-way analysis of variance (ANOVA) followed by Tukey's post hoc test (p < 0.05). RESULTS: Ionising radiation in combination with resveratrol or piceatannol activates the apoptosis process by internal and external pathways. Greater sensitivity of MCF7 cells compared to HCC38 cells to ionising radiation in combination with resveratrol is associated with a weaker antioxidant response of cells and reduced intensity of DNA damage repair. DNA repair induced by ionising radiation occurs more effectively in HCC38 cells than in MCF7 cells. CONCLUSION: Resveratrol has the highest radiosensitising potential among the tested stilbene for cells of both lines. The effectiveness of ionizing radiation in combination with resveratrol (to a lesser extent with piceatannol) is more significant in MCF7 than in HCC38 cells.

[Effect of Pterostilbene Regulating Nuclear Factor E2-Related Factor 2 on Apoptosis of Colon Cancer Cells in Vitro].

Objective To investigate the effects of pterostilbene on human colon cancer LoVo cells and study the regulatory mechanism of nuclear factor E2-related factor 2 (Nrf2) in the process of pterostilbene acting on LoVo cells. Methods LoVo cells were treated with different concentrations (5,10,20,40,60,80,100 µmol/L) of pterostilbene.Cell viability,migration,invasion,and apoptosis were examined by CCK-8,scratch,Transwell,and TUNEL assays,respectively.The mitochondrial membrane potential was measured by the mitochondrial membrane potential assay kit with JC-1.The reactive oxygen species level was measured by 2',7'-dichlorofluorescein diacetate.The protein levels of Nrf2,phosphorylated Nrf2,heme oxygenase 1,and apoptotic proteins (Bcl2 and Bax) were determined by Western blotting.In addition,cell viability,Nrf2 expression,and apoptosis rate were determined after co-application of the Nrf2-specific agonist sulforaphane. Results Compared with the control group,40,60,80,100 µmol/L pterostilbene reduced the viability of LoVo cells (P=0.014,P<0.001,P<0.001,P<0.001).Pterostilbene at 5,10,20 µmol/L did not show effects on cell viability but inhibited cell migration (P=0.008,P<0.001,P<0.001) and invasion (all P<0.001).Pterostilbene at 40,60,80 µmol/L increased apoptosis (P=0.014,P<0.001,P<0.001),promoted mitochondrial membrane potential depolarization (P=0.026,P<0.001,P<0.001) and reactive oxygen species accumulation (all P<0.001),and down-regulated the expression of phosphorylated Nrf2 (P=0.030,P<0.001,P<0.001),heme oxygenase 1 (P=0.015,P<0.001,P<0.001),and Bcl2 (P=0.039,P<0.001,P<0.001) in LoVo cells.Pterostilbene at 60,80 µmol/L down-regulated Nrf2 expression (P=0.001,P<0.001) and up-regulated Bax expression (both P<0.001).The application of sulforaphane reversed the effects of pterostilbene on cell viability (P<0.001),apoptosis (P<0.001),and Nrf2 expression (P=0.022). Conclusion Pterostilbene is a compound that can effectively inhibit colon cancer cells by inhibiting the Nrf2 pathway.

Electrostatically Engineered Tetraphenylethylene-Based Fluorescence Sensor for Protamine and Trypsin: Leveraging Aggregation-Induced Emission for Enhanced Sensitivity and Selectivity.

The accurate detection of Protamine and Trypsin, two biomolecules with significant clinical and biological relevance, presents a substantial challenge because of their structural peculiarities, low abundance in physiological fluids, and potential interference from other substances. Protamine, a cationic protein, is crucial for counteracting heparin overdoses, whereas Trypsin, a serine protease, is integral to protein digestion and enzyme activation. This study introduces a novel fluorescence sensor based on a (4-(1,2,2-tris(4-phosphonophenyl)vinyl)phenyl)phosphonic acid octasodium salt (TPPE), leveraging aggregation-induced emission (AIE) characteristics and electrostatic interactions to achieve selective and sensitive detection of these biomolecules. Through comprehensive optical characterization, including ground-state absorption, steady-state, and time-resolved emission spectroscopy, the interaction mechanisms and aggregation dynamics of TPPE with Protamine and Trypsin were elucidated. The sensor exhibits very high sensitivity (LOD: 1.45 nM for Protamine and 32 pM for Trypsin), selectivity, and stability, successfully operating in complex biological matrices, such as human serum and urine. Importantly, this sensor design underscores the synergy between the AIE phenomena and biomolecular interactions, offering a promising alternative for analytical applications in biomedical research and clinical diagnostics. The principles outlined herein open new avenues for the development of other AIE-based sensors, expanding the toolkit available for detecting a wide range of biomolecules using similar design strategies.

Dual combination of resveratrol and pterostilbene aqueous core nanocapsules for integrated prostate cancer targeting.

Aim: Development and evaluation of aqueous core nanocapsules (ACNs) of BCS-II-class drug like resveratrol (RSV) and pterostilbene (PTE) for prostate cancer.Materials & methods: Identify synergistic effects of molar ratios of RSV and PTE against PC-3 cell. Selected ratio of drugs was added to ACNs by double-emulsification-method using Box-Behnken design. Further, assessed for physicochemical characterization, release kinetics, compatibility, in vitro cytotoxicity, in vivo pharmacokinetic and biodistribution studies.Results: Selected 1:1 ratio of RSV and PTE had greatest synergy potential have smaller particle-size (128.1 ± 3.21 nm), zeta-potential (-22.12 ± 0.2 mV), 0.53 PDI, improved encapsulation (87% for RSV, 72% for PTE), stable, no systemic toxicity, high biodistributed/accumulated in prostate cells.Conclusion: ACNs exhibited high t1/2 (12.42 ± 1.92 hs) and 8.20 ± 8.21 hs Mean Residence Time and lower clearance, proving the high effectiveness for prostate cancer.

[Box: see text].

The autophagy-targeting compound V46 enhances antimicrobial responses to Mycobacteroides abscessus by activating transcription factor EB.

Mycobacteroides abscessus (Mabc) is a rapidly growing nontuberculous mycobacterium that poses a considerable challenge as a multidrug-resistant pathogen causing chronic human infection. Effective therapeutics that enhance protective immune responses to Mabc are urgently needed. This study introduces trans-3,5,4'-trimethoxystilbene (V46), a novel resveratrol analogue with autophagy-activating properties and antimicrobial activity against Mabc infection, including multidrug-resistant strains. Among the resveratrol analogues tested, V46 significantly inhibited the growth of both rough and smooth Mabc strains, including multidrug-resistant strains, in macrophages and in the lungs of mice infected with Mabc. Additionally, V46 substantially reduced Mabc-induced levels of pro-inflammatory cytokines and chemokines in both macrophages and during in vivo infection. Mechanistic analysis showed that V46 suppressed the activation of the protein kinase B/Akt-mammalian target of rapamycin signaling pathway and enhanced adenosine monophosphate-activated protein kinase signaling in Mabc-infected cells. Notably, V46 activated autophagy and the nuclear translocation of transcription factor EB, which is crucial for antimicrobial host defenses against Mabc. Furthermore, V46 upregulated genes associated with autophagy and lysosomal biogenesis in Mabc-infected bone marrow-derived macrophages. The combination of V46 and rifabutin exerted a synergistic antimicrobial effect. These findings identify V46 as a candidate host-directed therapeutic for Mabc infection that activates autophagy and lysosomal function via transcription factor EB.

[Resveratrol enhances the local antioxidant ability of the ovary in rats with polycystic ovary syndrome].

OBJECTIVE: To investigate the effects of resveratrol (RSV) on ovarian morphology, plasma anti-Müllerian hormone (AMH) and insulin-like growth factor 1 levels (IGF-1), and oxidative stress parameters in rats with polycystic ovary syndrome (PCOS). METHODS: Forty-six rats were randomly divided into a normal control (n = 12), a PCOS model control (n = 12), a rosiglitazone (RSG, n = 11), and an RSV group (n = 11). The PCOS model was established in the latter three groups by rejection of epidehydroandrosterone. The rats in the normal control and PCOS model control groups were treated by gavage of normal saline and those in the RSG and RSV groups by intragastric administration of RSG at 10 mg/(kg·d) and RSV at 3.0 mg/(kg·d), respectively. After 4 weeks of treatment, the ovarian histology was observed under the light microscope, the levels of plasma AMH and IGF-1 measured by ELISA, and the activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase (CAT) in the ovarian tissue detected using the Ellman, Sun and AEBI methods, respectively. RESULTS: After a 4-week treatment, statistically significant differences were observed in the above indicators between the normal control and PCOS model control groups (P<0.05). The rats treated with RSG and RSV also showed significant differences in these parameters from the model controls (P<0.05). CONCLUSION: RSV can enhance the local antioxidant capacity of the ovary, reduce the levels of AMH and IGF-1, and improve the morphology of the ovarian tissue in rats with PCOS, indicating its potential value in the treatment of PCOS.

Polydatin from Polygoni Cuspidati Rhizoma et Radix regulates glucolipid metabolism in the liver of diabetic rats: Multiscale analysis of network pharmacology and multiomics.

BACKGROUND: Polygoni Cuspidati Rhizoma et Radix (Huzhang in Chinese), refers to the root and rhizome of Polygonum cuspidatum Sieb. et Zucc. Huzhang is commonly used in clinical practice for the prevention and treatment of diabetes and its complications, but its active components and regulatory mechanisms have not yet been thoroughly analyzed. PURPOSE: The network pharmacology combined with multi-omics analysis will be employed to dissect the substance basis and action mechanism of Huzhang in exerting its anti-diabetic activity. METHODS: This study employed phenotypic indicators for baseline assessment, followed by integrated analysis using network pharmacology, metabolomics, transcriptomics, and qPCR technology to elucidate the active components and pharmacological mechanisms of Huzhang. RESULTS: The analysis of network pharmacology revealed that polydatin is a potential active component responsible for the anti-T2DM pharmacological effects of Huzhang. In vivo experimental results demonstrated that polydatin significantly regulates blood glucose, lipid levels, liver function, and liver pathological damage in diabetic rats. Analysis results from transcriptomics, metabolomics, and qPCR validation showed that polydatin comprehensively regulates glucose and lipid metabolism in T2DM by modulating bile acid metabolism, fatty acid oxidation, and lipogenesis. CONCLUSION: Polydatin is a key component of Huzhang in treating T2DM, and its regulatory mechanisms are diverse, indicating significant development potential.

Glowing discoveries: Schiff base-cyanostilbene probes illuminating metal ions and biological entities.

Schiff bases featuring cyanostilbene units have emerged as versatile and highly effective probes for the selective detection of various metal ions as well as biologically important species. This review comprehensively highlights recent advances in the development and application of the probes, which exhibit remarkable Aggregation-Induced Emission (AIE), Twisted Intramolecular Charge Transfer (TICT), and Excited-State Intramolecular Proton Transfer (ESIPT) properties. These unique structural characteristics facilitate their potential applications in the detection of biologically important metal ions such as Zn2+, Fe3+, Cu2+, Hg2+ and Co2+ ions with high sensitivity and selectivity. Furthermore, these probes have demonstrated significant potential in the recognition of vital biological species, including arginine, hydrazine and hypochlorite (ClO-). The present review discusses the underlying detection mechanisms, emphasizing the role of the Schiff base and cyanostilbene moieties for the selective detection of particular biologically important entities. Moreover, this discussion highlights the practical applications, problems, and future directions in this fast-growing field, emphasizing the vital importance of these probes in both analytical chemistry and bioassays.

Elevated cerebral blood flow proxy with increased beta-amyloid burden in Alzheimer's disease preclinical phase evaluated by dual-phase 18F-florbetaben positron emission tomography.

This study investigated the earliest change of cerebral blood flow (CBF) and its relationship with ß-amyloid (Aß) burden in preclinical Alzheimer's disease (AD) employing dual-phase 18F-florbetaben (FBB) PET. Seventy-one cognitively normal (NC) individuals were classified as Aß negative (Aß-NC) or positive (Aß+NC) based on two different cutoff values: an SUVR of > 1.08 and a Centiloid scale of > 20. The PET scans were acquired in two phases: an early phase (0-10 min, eFBB) and a delayed phase (90-110 min, dFBB), which were averaged to generate single-frame images for each phase. Furthermore, an R1 parametric map was generated from the early phase data using a simplified reference tissue model. We conducted regional and voxel-based analyses to compare the eFBB, dFBB, and R1 images between the Aß positive and negative groups. In addition, the correlations between the CBF proxy R1 and the dFBB SUVR were analyzed. The Aß+NC group showed significantly higher dFBB SUVR in both the global cerebral cortex and target regions compared to the Aß-NC group, while no significant differences were observed in eFBB SUVR between the two groups. Furthermore, the Aß+NC group exhibited significantly higher R1 values, a proxy for cerebral perfusion, in both the global cerebral cortex and target regions compared to the Aß-NC group. Significant positive correlations were observed between R1 and dFBB SUVR in both the global cerebral cortex and target regions, which remained significant after controlling for demographics and cognitive profiles, except for the medial temporal and occipital cortices. The findings reveal increased CBF in preclinical AD and a positive correlation between CBF and amyloid pathology. The positive correlation between R1 and amyloid burden may indicate a compensatory mechanism in the preclinical stage of Alzheimer's disease, but to elucidate this hypothesis, further longitudinal observational studies are necessary.

Structurally Diverse Stilbenoids as Potent α-Glucosidase Inhibitors with Antidiabetic Effect from Morus alba.

Fifteen stilbenoid derivatives, including five previously undescribed ones (albaphenols A-E, 1-5) with diverse scaffolds, were obtained from the well-known agricultural economic tree Morus alba. Their structures, including absolute stereochemistries, were fully characterized by detailed interpretation of spectroscopic data and quantum chemical computational analyses of nuclear magnetic resonance (NMR) and electric circular dichroism (ECD). Albaphenol A (1) features an unprecedented rearranged carbon skeleton incorporating a novel 2-oxaspiro[bicyclo[3.2.1]octane-6,3'-furan] motif; albaphenol C (3) is likely derived from a cometabolite through an interesting intramolecular transesterification reaction; and albaphenol E (5) bears a cleavage-reconnection scaffold via a dioxane ring. All of the compounds exhibited significant inhibition against the diabetic target α-glucosidase, with low to submicromole IC50 values (0.70-8.27 µM), and the binding modes of selected molecules with the enzyme were further investigated by fluorescence quenching, kinetics, and molecular docking experiments. The antidiabetic effect of the most active and abundant mulberrofuran G (6) was further assessed in vivo in diabetic mice, revealing potent antihyperglycemic activity and comparable antidiabetic efficacy to the clinical drug acarbose.

Wild Vitis Species as Stilbenes Sources: Cane Extracts and Their Antibacterial Activity against Listeria monocytogenes.

Grapevines (Vitis spp.) produce several valuable polyphenol-type secondary metabolites including various stilbenoids. Although the potential application of stilbenes may offer alternative solutions to food safety or health challenges, only little information is available on their antibacterial activity against foodborne pathogens. In this work, high-performance liquid chromatography was used to analyze the stilbenoid profile of various wild Vitis species, including V. amurensis, V. davidii, V. pentagona, and V. romanetii, selected from the gene bank for grapes at the University of Pécs, Hungary. We found that the stilbene profile of cane extracts is strongly genotype-dependent, showing the predominant presence of ε-viniferin with a wide concentration range ≈ 320-3870 µg/g dry weight. A novel yet simple and efficient extraction procedure was developed and applied for the first time on grape canes, resulting in ε-viniferin-rich crude extracts that were tested against Listeria monocytogenes, an important foodborne pathogen. After 24 h exposure, V. pentagona and V. amurensis crude extracts completely eliminated the bacteria at a minimum bactericidal concentration of 42.3 µg/mL and 39.2 µg/mL of ε-viniferin, respectively. On the other hand, V. romanetii extract with 7.8 µg/mL of ε-viniferin resulted in 4 log reduction in the viable bacterial cells, while V. davidii extract with 1.4 µg/mL of ε-viniferin did not show significant antibacterial activity. These findings indicate that the ε-viniferin content was directly responsible for the antibacterial effect of cane extract. However, pure ε-viniferin (purity > 95%) required a higher concentration (188 µg/mL) to eradicate the bacteria under the same conditions, suggesting the presence of other antibacterial compounds in the cane extracts. Investigating the onset time of the bactericidal action was conducted through a kinetic experiment, and results showed that the reduction in living bacterial number started after 2 h; however, the bactericidal action demanded 24 h of exposure. Our results revealed that the canes of V. pentagona and V. amurensis species are a crucial bio-source of an important stilbene with antimicrobial activity and health benefits.

Neuroprotective effects of the combined treatment of resveratrol and urapidil in experimental cerebral ischemia-reperfusion injury in rats.

PURPOSE: To evaluate the neuroprotective effect of resveratrol, urapidil, and a combined administration of these drugs against middle cerebral artery occlusion (MCAO) induced ischemia/reperfusion (IR) injury model in rats. METHODS: Thirty-five rats were divided into five groups of seven animals each. Animals in IR, IR resveratrol (IRr), IR urapidil (IRu), and IR + combination of resveratrol and urapidil (IRc) were exposed to MCAO induced cerebral ischemia reperfusion injury model. Rats in IRr and IRu groups received 30-mg/kg resveratrol and 5-mg/kg urapidil respectively. Animals in IRc received a combined treatment of both drugs. At the end of the study, brain tissues were used for oxidative stress (malondialdehyde, glutathione, and superoxide dismutase), pro-apoptotic caspase-3, anti-apoptotic Bcl-2, and pro-inflammatory tumor necrosis factor-α cytokine level measurements. RESULTS: The MCAO model successfully replicated IR injury with significant histopathological changes, elevated tissue oxidative stress, and upregulated apoptotic and inflammatory protein expression in IR group compared to control group (p < 0.001). All parameters were significantly alleviated in IRr group compared to IR group (all p < 0.05). In IRu group, all parameters except for caspase-3 and Bcl-2 were also significantly different than IR group (all p < 0.05). The IRc group showed the biggest difference compared to IR group in all parameters (all p < 0.001). The IRc had higher superoxide dismutase and Bcl-2 levels, and lower caspase-3 levels compared to both IRr and IRu groups (all p < 0.05). Also, the IRc group had lower MDA and TNF-α levels compared to IRu group (all p < 0.05). CONCLUSIONS: The results indicate that combined treatment of resveratrol and urapidil may be a novel strategy to downregulate neurodegeneration in cerebral IR injury.

Targeting the Tumor Vascular Supply to Enhance Radiation Therapy Administered in Single or Clinically Relevant Fractionated Schedules.

This pre-clinical study was designed to demonstrate how vascular disrupting agents (VDAs) should be administered, either alone or when combined with radiation in clinically relevant fractionated radiation schedules, for the optimal anti-tumor effect. CDF1 mice, implanted in the right rear foot with a 200 mm3 murine C3H mammary carcinoma, were injected with various doses of the most potent VDA drug, combretastatin A-1 phosphate (CA1P), under different schedules. Tumors were also locally irradiated with single-dose, or stereotactic (3 × 5-20 Gy) or conventional (30 × 2 Gy) fractionation schedules. Tumor growth and control were the endpoints used. Untreated tumors had a tumor growth time (TGT5; time to grow to 5 times the original treatment volume) of around 6 days. This increased with increasing drug doses (5-100 mg/kg). However, with single-drug treatments, the maximum TGT5 was only 10 days, yet this increased to 19 days when injecting the drug on a weekly basis or as three treatments in one week. CA1P enhanced radiation response regardless of the schedule or interval between the VDA and radiation. There was a dose-dependent increase in radiation response when the combined with a single, stereotactic, or conventional fractionated irradiation, but these enhancements plateaued at around a drug dose of 25 mg/kg. This pre-clinical study demonstrated how VDAs should be combined with clinically applicable fractionated radiation schedules for the optimal anti-tumor effect, thus suggesting the necessary pre-clinical testing required to ultimately establish VDAs in clinical practice.

[Inhibition Effect of Resveratrol on Spontaneous Senescence of Human Bone Marrow Derived Mesenchymal Stem Cells].

OBJECTIVE: To explore whether Resveratrol (RSV) can inhibit the spontaneous senescence of human bone marrow-derived mesenchymal stem cells (MSC). METHODS: MSC were serially cultured to passage 13 and passage 15 to establish model groups exhibiting spontaneous senescence, respectively. MSC at passage 13 and passage 15 were treated with 5 nmol/L RSV for 48 h to establish the RSV-treated groups. SA-ß-Gal staining was used to detect cell senescence. MTT assay was used to detect cell proliferation. RT-PCR method was used to detect senescenceassociated telomerase activity. Western blot was used to detect the senescence-associated protein level of the phosphorylated-mTOR. RESULTS: SA-ß-Gal staining showed that the senescent cells of MSC in RSV-treated group was significantly less than those in the model group (RSV group compared with model group at passage 13, P < 0.05; RSV group compared with model group at passage 15, P < 0.01). The cell proliferation ability of MSC in RSV-treated group was significantly higher than those in model group, at 72 h in passage 13, there was significant difference between RSV-treated group and model group (P < 0.05). RT-PCR results showed that the hTERT mRNA expression of MSC in RSV-treated group was higher than that in model group, which was significantly different between RSV-treated group and model group at passage 13 (P < 0.05). Western blot results showed that the phosphorylated (Ser2448)-mTOR level of MSC in RSV-treated group was lower than that in model group, which was significantly different between RSV-treated group and model group at passage 13 (P < 0.05). CONCLUSION: RSV can inhibit the spontaneous senescence of human MSC by mediating mTOR activity.

Inhibitory effects of resveratrol on platelet activation and thrombosis in colon cancer through regulation of the MAPK and cGMP/VASP pathways.

Thrombosis is the primary cause of death in patients with cancer. Resveratrol inhibits platelet activation, a crucial pathophysiological basis of thrombosis, in healthy individuals. However, its effects and mechanisms of action in patients with colon cancer remain unknown. Here, we investigated the effect of resveratrol on platelet adhesion and aggregation in patients with colon cancer. Through numerous in vitro and in vivo analyses, including flow cytometry, western blotting, ELISA, and immunofluorescence and colon cancer rat models, we demonstrated that resveratrol reduced thrombosis in patients with colon cancer by inhibiting the phosphorylation of the MAPK and activating the cyclic-GMP/vasodilator-stimulated phosphoprotein pathway. These findings demonstrate the potential of resveratrol in reducing thrombosis in patients with colon cancer and could be used to develop novel therapeutic strategies for this condition.