Subchronic oral toxicity and cardiovascular safety pharmacology studies of resveratrol, a naturally occurring polyphenol with cancer preventive activity

Harnessing the therapeutic potential of phytochemicals in neuroblastoma

Neuroblastomas are the most common solid tumors outside of the brain that originate from immature neural crest cells, accounting for about 10% of all pediatric malignancies. The treatment for neuroblastomas involves a multimodal schedule, including surgery, radiation, chemotherapy, and immunotherapy. All these modalities are limited by side effects that might be severe, poor prognosis, and a high risk of recurrence. In the quest for additional therapeutic approaches, phytochemicals have attracted attention owing to their reported antitumor properties, safety, and multimechanistic mode of action. Several studies have used plant-derived bioactive compounds such as phenolics and flavonoids, suggesting modulation of biomolecules and signal transduction pathways involved in neuroblastoma. We reviewed the findings of recent preclinical and clinical studies demonstrating the effects of phytochemicals on neuroblastoma, shedding light on their molecular mechanism of action and potential therapeutic applications.

Comparative Neuroprotective Potential of Nanoformulated and Free Resveratrol Against Cuprizone-Induced Demyelination in Rats

Demyelination is a frequent yet crippling neurological disease associated with multiple sclerosis (MS). The cuprizone (CZ) model, which causes demyelination through oxidative stress and neuroinflammation, is a popular tool used by researchers to examine this process. The polyphenol resveratrol (RESV) has become a promising neuroprotective agent in seeking for efficient therapies. In a rat model given CZ, we created and examined iron oxide nanoparticles (IONPs) loaded with RESV (IONP-RESV) to see how effective they were as a therapeutic agent against free RESV. According to molecular mechanisms, exposure to CZ resulted in a marked downregulation of myelin proteolipid protein (PLP) expression and an overexpression of the inflammatory markers tumor necrosis factor-α (TNF-α) and S100β, which are indicators of demyelination and neuroinflammation. It is remarkable that these CZ-induced alterations could be reversed by therapy with either RESV or IONP-RESV. Interestingly, IONP-RESV showed even stronger anti-inflammatory activity, as shown by a more noticeable downregulation of TNF-α and S100β expression. These results were confirmed by histopathological examination of the cerebral cortices. Our findings support the better neuroprotective benefits of RESV-loaded IONPs over free RESV in reducing demyelination and neuroinflammation brought on by CZ. Owing to their pro-remyelinating, anti-inflammatory, and antioxidant properties, RESV-loaded IONPs show promise as a neurotherapeutic intervention in the future for neurological diseases such as multiple sclerosis.

Analysis of VEGFR-2 and PDGFR-β expression in canine splenic hemangiosarcoma to identify drug repositioning candidates

Splenic tumors are very common in dogs, and canine hemangiosarcoma (HSA) is one of the most important malignant splenic tumors. Surgery followed by chemotherapy (anthracycline-based protocols) is recommended for treating canine HSA; however, patients still do not achieve long-term survival. Therefore, this research aimed to assess vascular endothelial growth factor receptor-2 (VEGFR-2) and platelet-derived growth factor receptor-β (PDGFR-β) gene expression in formalin-fixed tissues, evaluate the quality of mRNA for quantitative polymerase chain reaction (qPCR) analysis and identify drug repositioning candidates based on VEGFR-2 and PDGFR-β. qPCR analysis identified the relative expression of heterogeneous VEGFR-2 and PDGFR-β, with samples showing no transcripts or very low expression and those with higher relative quantification for both genes. We then used immunohistochemistry to correlate the relative quantification of VEGFR-2 and PDGFR-β transcripts with respective higher protein expression to validate our results. In the next step, we evaluated drug repositioning candidates and identified small molecule inhibitors (i.e. sorafenib) and natural compounds (curcumin and resveratrol) with the ability to block VEGFR-2 and PDGFR-β genes. Overall, our results indicated that VEGFR-2 and PDGFR-β expression is highly variable among canine HSA samples and different drugs can block the expression of both genes. Therefore, a personalized approach could be useful for selecting anti-VEGFR-2 and PDGFR-β therapies and both genes are potential candidates for future oncological panels.

The potential application and molecular mechanisms of natural products in the treatment of allergic rhinitis: A review

BACKGROUNDS

Allergic rhinitis (AR) is a non-infectious chronic inflammation of the nasal mucosa mainly mediated by immunoglobulin E (IgE) in atopic individuals after exposure to allergens. The application of AR guideline-recommended pharmacotherapies can rapidly relieve symptoms of AR but with poor long-term efficacy, and many of these therapies have side effects. Many natural products and their derivatives have shown potential therapeutic effects on AR with fewer side effects.

OBJECTIVES

This review aims to expand understanding of the roles and mechanisms of natural compounds in the treatment of AR and to highlight the importance of utilizing natural products in the treatment of AR.

MATERIAL AND METHOD

We conducted a systematic literature search using PubMed, Web of Science, Google Scholar, and Clinical Trials. The search was performed using keywords including natural products, natural compounds, bioproducts, plant extracts, naturally derived products, natural resources, allergic rhinitis, hay fever, pollinosis, nasal allergy. Comprehensive research and compilation of existing literature were conducted.

RESULTS

This article provided a comprehensive review of the potential therapeutic effects and mechanisms of natural compounds in the treatment of AR. We emphasized that natural products primarily exert their effects by modulating signalling pathways such as NF-κB, MAPKs, STAT3/ROR-γt/Foxp3, and GATA3/T-bet, thereby inhibiting the activation and expansion of allergic inflammation. We also discussed their toxicity and clinical applications in AR therapy.

CONCLUSION

Taken together, natural products exhibit great potential in the treatment of AR. This review is also expected to facilitate the application of natural products as candidates for treating AR. Furthermore, drug discovery based on natural products has a promising prospect in AR treatment.

Comprehensive and critical view on the anti-inflammatory and immunomodulatory role of natural phenolic antioxidants

The immune response encompasses innate and adaptive immunity, each with distinct and specific activities. The innate immune system is constituted by phagocytic cells, macrophages, monocytes and neutrophils, the cascade system, and different classes of receptors such as toll-like receptors that are exploited by the innate immune cells. The adaptive immune system is antigen-specific, encompassing memory lymphocytes and the corresponding specific receptors. Inflammation is understood as an activation of different signaling pathways such as toll-like receptors or nuclear factor kappa-light-chain-enhancer of activated B cells, with an increase in nitric oxide, inflammatory cytokines and chemokines. Increased oxidative stress has been identified as main source of chronic inflammation. Phenolic antioxidants modulate the activities of lymphocytes and macrophages by impacting cytokines and nitric oxide release, exerting anti-inflammatory effect. The nuclear-factor kappa-light-chain-enhancer of activated B cells signaling pathway and the mitogen-activated protein kinase pathway are targeted, alongside an increase in nuclear factor erythroid 2-related factor mediated antioxidant response, triggering the activity of antioxidant enzymes. The inhibitive potential on phospholipase A2, cyclooxygenase and lipoxygenase in the arachidonic acid pathway, and the subsequent reduction in prostaglandin and leukotriene generation, reveals the potential of phenolics as inflammation antagonists. The immunomodulative potential encompasses the capacity to interfere with proinflammatory cytokine synthesis and with the expression of the corresponding genes. A diet rich in antioxidants can result in prevention of inflammation-related pathologies. More investigations are necessary to establish the role of these antioxidants in therapy. The appropriate delivery system and the prooxidant effects exhibited at large doses, or in the presence of heavy metal cations should be regarded.

Deciphering resveratrol's role in modulating pathological pain: From molecular mechanisms to clinical relevance

Pathological pain, a multifaceted and debilitating ailment originating from injury or post-injury inflammation of the somatosensory system, poses a global health challenge. Despite its ubiquity, reliable therapeutic strategies remain elusive. To solve this problem, resveratrol, a naturally occurring nonflavonoid polyphenol, has emerged as a potential beacon of hope owing to its anti-inflammatory, antioxidant, and immunomodulatory capabilities. These properties potentially position resveratrol as an efficacious candidate for the management of pathological pain. This concise review summaries current experimental and clinical findings to underscore the therapeutic potential of resveratrol in pathological pain, casting light on the complex underlying pathophysiology. Our exploration suggests that resveratrol may exert its analgesic effect by the modulating pivotal signaling pathways, including PI3K/Akt/mTOR, TNFR1/NF-κB, MAPKs, and Nrf2. Moreover, resveratrol appears to attenuate spinal microglia activation, regulate primary receptors in dorsal root sensory neurons, inhibit pertinent voltage-gated ion channels, and curb the expression of inflammatory mediators and oxidative stress responses. The objective of this review is to encapsulate the pharmacological activity of resveratrol, including its probable signaling pathways, pharmacokinetics, and toxicology pertinent to the treatment of pathological pain. Hopefully, we aim to map out promising trajectories for the development of resveratrol as a potential analgesic.

Phytochemical profiling, in vitro biological activities, and in silico (molecular docking and absorption, distribution, metabolism, excretion, toxicity) studies of Polygonum cognatum Meissn

Polygonum cognatum Meissn, a perennial herbaceous belonging to the Polygonaceae family, is an aromatic plant. High-performance liquid chromatography/diode array detector method was developed and validated for the phytochemical analysis of the plant. Also, various methods were used to investigate the antioxidant, antimicrobial, and cytotoxic activities of the methanolic extracts. Antioxidant activities were researched by 2,2'-diphenyl-1-picrylhydrazyl and cupric reducing antioxidant capacity methods. Among the tested standard microbial strains, Candida albicans was found to be more sensitive with a 24.60 ± 0.55 mm inhibition zone according to the diffusion tests. In the microdilution tests, the minimum inhibitory concentration and minimum bactericidal/fungicidal concentration values were 4.75 and ≥ 4.75 mg/mL, respectively, for all tested pathogens. Human colon carcinoma cells were used to investigate cytotoxicity by using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide analysis (IC50  = 2891 μg/mL for Plant A, IC50  = 3291 μg/mL for Plant B). Molecular docking and absorption, distribution, metabolism, excretion, and toxicity analysis were used to explain inhibition mechanisms of major phenolic compounds of plants against Tankyrase 1, Tankyrase 2 enzymes, and deoxyribonucleic acid gyrase subunit B and found compatible with experimental results.

Resveratrol prevents Drp1-mediated mitochondrial fission in the diabetic kidney through the PDE4D/PKA pathway

To explore the role of PDE4D in diabetic nephropathy (DN) and investigate whether resveratrol protects against DN via inhibiting PDE4D. Diabetic db/db mouse and glomerular mesangial cell line (GMCs) were used to investigate the role of PDE4D and the protective effect of resveratrol on renal fibrosis under high glucose (HG) environment. Resveratrol alleviated the progress of DN via inhibiting mitochondrial fragmentation and restoring the expression of PDE4D, PKA, phosphorylated Drp1-Ser637 and Drp1 in kidney of db/db mice. In HG-exposed GMCs, resveratrol treatment decreased the expression of PDE4D, increased PKA level, and inhibited Drp1-mediated mitochondrial fission. In contrast, PDE4D over-expression blunted the inhibitory effects of resveratrol on Drp1 expression and mitochondrial fission. Moreover, PKA inhibitor H89 blunted the effects of resveratrol on phosphorylated Drp1-Ser637 expression and mitochondrial fission in HG-treated GMCs. Inhibition of mitochondrial fission with Drp1 inhibitor Mdivi-1 alleviated mitochondrial dysfunction in GMCs under HG. These findings indicate PDE4D plays an important role in the process of DN. Resveratrol attenuates the development of DN by preventing mitochondrial fission through inhibiting PDE4D, which regulates the expression of phosphorylated Drp1-Ser637 directly.

Potential of resveratrol in the treatment of interstitial lung disease

Interstitial lung disease (ILD) is a heterogeneous group of diseases characterized by lung injury caused by lung fibroblast proliferation, interstitial inflammation, and fibrosis. Different cell signal transduction pathways are activated in response to various proinflammatory or fibrotic cytokines, such as IL-6, and these cytokines are increased in different ILDs. The overexpressed cytokines and growth factors in ILD can activate TGF-β/Smad2/3/4, NF-κB, and JAK/STAT signal transduction pathways, promote the activation of immune cells, increase the release of pro-inflammatory and pro-fibrotic factors, differentiate fibroblasts into myofibroblasts, and promote the occurrence and development of ILD. This finding suggests the importance of signal transduction pathways in patients with ILD. Recent evidence suggests that resveratrol (RSV) attenuates excessive inflammation and pulmonary fibrosis by inhibiting the TGF-β/Smad2/3/4, NF-κB, and JAK/STAT signal transduction pathways and overactivation of immune cells. In this review, advances in lung protection and the underlying mechanisms of RSV are summarized, and the potential efficacy of RSV as a promising treatment option for ILD is highlighted.

Redox Biomarkers Assessment after Oral Administration of Wine Extract and Grape Stem Extract in Rats and Mice

Wine and by-products of the winemaking process, such as grape stems, are rich in bioactive polyphenolic compounds that might be beneficial for animal and human health. In recent years, the administration of dietary polyphenols with strong antioxidant and cytoprotective properties has constituted an emerging line of research interest toward disease prevention. However, in scientific literature, only a limited number of studies have investigated the safety and the toxicological risks of polyphenolic compounds in vivo. Based on the above, the purpose of the present study was two-fold: first, to examine the effects of oral administration of a grape stem extract, derived from the Greek red wine Mavrodaphne, on mice redox biomarkers; and second, to investigate the biological effects of oral administration of a wine extract, derived from the emblematic Greek red wine Xinomavro, on rats. Toward this purpose, body weight, growth rate, hematological, biochemical, and histopathological parameters, as well as a panel of redox biomarkers, were examined. According to our results, the administration of Mavrodaphne grape stem extract in mice induced alterations in redox homeostasis, preventing mice from the adverse effects of lipid peroxidation. Contrariwise, the administration of Xinomavro wine extract induced both beneficial and harmful outcomes on rat redox status determined by the examined tissue. Collectively, our study reports that the Mavrodaphne grape stem extract, a serious pollutant when disposed in environmental matrices, is an important source of bioactive polyphenolic compounds that could protect from oxidative damage and improve animal and human health. Finally, the Xinomavro wine extract exerts tissue-specific changes in redox balance, which are indicative of the complexity that characterizes the biological systems.

Review of the Potential Therapeutic Effects and Molecular Mechanisms of Resveratrol on Endometriosis

Endometriosis is a hormone-dependent inflammatory disease characterized by the existence of endometrial tissues outside the uterine cavity. Pharmacotherapy and surgery are the current dominant management options for endometriosis. The greater incidence of recurrence and reoperation after surgical treatment as well as the adverse effects of medical approaches predispose patients to potential limitations for their long-term usage. Consequently, it is essential to explore novel supplementary and alternative drugs to ameliorate the therapeutic outcomes of endometriotic patients. Resveratrol is a phenolic compound that has attracted increasing interest from many researchers due to its pleiotropic biological activities. Here, we review the possible therapeutic efficacies and molecular mechanisms of resveratrol against endometriosis based on in vitro, animal, and clinical studies. The potential mechanisms of resveratrol include anti-proliferative, pro-apoptotic, anti-angiogenic, anti-oxidative stress, anti-invasive and anti-adhesive effects, thereby suggesting that resveratrol is a promising candidate for endometriosis. Because most studies have investigated the effectiveness of resveratrol on endometriosis via in vitro trials and/or experimental animal models, further high-quality clinical trials should be undertaken to comprehensively estimate the clinical application feasibility of resveratrol on endometriosis.

Selected Plant-Derived Polyphenols as Potential Therapeutic Agents for Peripheral Artery Disease: Molecular Mechanisms, Efficacy and Safety

Vascular diseases, such as peripheral artery disease (PAD), are associated with diabetes mellitus and a higher risk of cardiovascular disease and even death. Surgical revascularization and pharmacological treatments (mainly antiplatelet, lipid-lowering drugs, and antidiabetic agents) have some effectiveness, but the response and efficacy of therapy are overly dependent on the patient’s conditions. Thus, the demand for new cures exists. In this regard, new studies on natural polyphenols that act on key points involved in the pathogenesis of vascular diseases and, thus, on PAD are of great urgency. The purpose of this review is to take into account the mechanisms that lead to endothelium dysfunction, such as the glycoxidation process and the production of advanced glycation end-products (AGEs) that result in protein misfolding, and to suggest plant-derived polyphenols that could be useful in PAD. Thus, five polyphenols are considered, baicalein, curcumin, mangiferin, quercetin and resveratrol, reviewing the literature in PubMed. The key molecular mechanisms and preclinical and clinical studies of each selected compound are examined. Furthermore, the safety profiles of the polyphenols are outlined, together with the unwanted effects reported in humans, also by searching the WHO database (VigiBase).

Protective effects of resveratrol against genotoxicity induced by nano and bulk hydroxyapatite in Drosophila melanogaster

Hydroxyapatite (HAp) is a naturally occurring calcium phosphate mineral predominantly used for its biocompatibility in a number of areas such as bone grafting, prosthesis coating in dentistry, and targeted drug delivery. Since the nano form of HAp (nHAp) has gained popularity attributed to a re-mineralizing effect in dental repair procedures, concerns have been raised over safety and biocompatibility of these nanoparticles (NP). This study, therefore, aimed to (1) investigate mechanisms of potential genotoxicity and enhanced generation of reactive oxygen species (ROS) initiated by bulk and nano forms of HAp and (2) test in vivo whether resveratrol, a type of natural phenol, might mitigate the extent of potential DNA damage. The size of nHAp was determined to be 192.13 ± 9.91 nm after dispersion using transmission electron microscopy (TEM). Drosophila melanogaster was employed as a model organism to determine the genotoxic potential and adverse effects of HAp by use of (comet assay), mutagenic and recombinogenic activity (wing spot test), and ROS-mediated damage. Drosophila wing-spot tests demonstrated that exposure to nontoxic bulk and nHAp concentrations (1, 2.5, 5 or 10 mM) produced no significant recombination effects or mutagenicity. However, bulk and nHAp at certain doses (2.5, 5 or 10 mM) induced genotoxicity in hemocytes and enhanced ROS production. Resveratrol was found to ameliorate the genotoxic effects induced by bulk HAp and nHAp in comet assay. Data demonstrate that treatment with nano and bulk Hap-induced DNA damage and increased ROS generation D. melanogaster which was alleviated by treatment with resveratrol.

Role of sirtuin1 in impairments of emotion-related behaviors in mice with chronic mild unpredictable stress during adolescence

Long-term exposure to physical and/or psychosocial stress during early life and/or adolescence increases the risk of psychiatric disorders such as major depressive disorder and anxiety disorders. However, the molecular mechanisms underlying early stress-induced brain dysfunction are poorly understood. In the present study, mice at 4 weeks old were subjected to chronic mild unpredictable stress (CMUS) for 4 weeks, and subsequently to assays of emotion-related behaviors. Thereafter, they were sacrificed and their brains were collected for real-time quantitative polymerase chain reaction (RT-qPCR). Mice with CMUS during adolescence showed despair behavior, anxiety-like behavior, social behavior deficits, and anhedonia in forced-swim, marble-burying, social interaction, and sucrose preference tests, respectively. Additionally, RT-qPCR revealed that the expression levels of sirtuin1 (SIRT1), a NAD⁺-dependent deacetylase that mediates stress responses, were down-regulated in the prefrontal cortex and hippocampus of mice with CMUS compared with control mice. Next, to investigate the pathophysiological role of decreased Sirt1 expression levels in stress-induced behavioral deficits, we assessed the effects of resveratrol, a pharmacological activator of SIRT1, in mice exposed to CMUS. Chronic treatment with resveratrol prevented -induced social behavior deficits and depression-like behaviors. These results suggest that CMUS during adolescence decreases Sirt1 expression in the brain, leading to deficits in emotional behavior. Accordingly, SIRT1 activators, such as resveratrol, may be preventive agents against abnormalities in emotional behavior following stress during an immature period.

Antioxidant and Antimicrobial Biofoil Based on Chitosan and Japanese Knotweed (Fallopia japonica, Houtt.) Rhizome Bark Extract

A 70% ethanol_(aq) extract of the rhizome bark of the invasive alien plant species Japanese knotweed (JKRB) with potent (in the range of vitamin C) and stable antioxidant activity was incorporated in 1% w/v into a chitosan biofoil, which was then characterized on a lab-scale. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay confirmed the antioxidant activity of the JKRB biofoil upon contact with the food simulants A, B, C, and D1 (measured half-maximal inhibitory concentrations—IC₅₀) and supported the Folin–Ciocalteu assay result. The migration of the antioxidant marker, (−)-epicatechin, into all food simulants (A, B, C, D1, D2, and E) was quantified using liquid chromatography hyphenated to mass spectrometry (LC-MS). Calculations showed that 1 cm² of JKRB biofoil provided antioxidant activity to ~0.5 L of liquid food upon 1 h of contact. The JKRB biofoil demonstrated antimicrobial activity against Gram-positive bacteria. The incorporation of JKRB into the chitosan biofoil resulted in improved tensile strength from 0.75 MPa to 1.81 MPa, while elongation decreased to 28%. JKRB biofoil’s lower moisture content compared to chitosan biofoil was attributed to the formation of hydrogen bonds between chitosan biofoil and JKRB compounds, further confirmed with attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR). The JKRB biofoil completely degraded in compost in 11 days. The future upscaled production of JKRB biofoil from biowastes for active packaging may support the fights against plastic waste, food waste, and the invasiveness of Japanese knotweed, while greatly contributing to the so-called ‘zero-waste’ strategy and the reduction in greenhouse gas emissions.

Resveratrol: Potential Application in Sepsis

Sepsis is a life-threatening organ dysfunction syndrome caused by host response disorders due to infection or infectious factors and is a common complication of patients with clinical trauma, burns, and infection. Resveratrol is a natural polyphenol compound that is a SIRT-1 activator with anti-inflammatory, antiviral, antibacterial, antifungal inhibitory abilities as well as cardiovascular and anti-tumor protective effects. In recent years, some scholars have applied resveratrol in animal models of sepsis and found that it has an organ protective effect and can improve the survival time and reduce the mortality of animals with sepsis. In this study, Medline (Pubmed), embase, and other databases were searched to retrieve literature published in 2021 using the keywords “resveratrol” and “sepsis,” and then the potential of resveratrol for the treatment of sepsis was reviewed and prospected to provide some basis for future clinical research.

An oral hydrogel carrier for delivering resveratrol into intestine-specific target released with high encapsulation efficiency and loading capacity based on structure-selected alginate and pectin

Resveratrol (RES) has many beneficial effects on the human body, but it is always unstable, resulting in low oral bioavailability, especially in the gastrointestinal tract.

Targeting the Wnt Signaling Pathway in Liver Fibrosis for Drug Options: An Update

Liver fibrosis is a life-threatening disease, with challenging morbidity and mortality for healthcare systems worldwide. It imparts an enormous economic burden to societies, making continuous research and informational updates about its pathogenesis and treatment crucial. This review's focus is on the current knowledge about the Wnt signaling pathway, serving as an important pathway in liver fibrosis development and activation of hepatic stellate cells (HSCs). Two types of Wnt pathways are distinguished, namely the ß-catenin-dependent canonical and non-canonical Ca²⁺ or planar cell polarity (PCP)-dependent pathway. The dynamic balance of physiologically healthy liver and hepatocytes is disturbed by repeated liver injuries. Activation of the ß-catenin Wnt pathway prevents the regeneration of hepatocytes by the replacement of extracellular matrix (ECM), leading to the appearance of scar tissue and the formation of regenerated nodular hepatocytes, lacking the original function of healthy hepatocytes. Therefore, liver function is reduced due to the severely advanced disease. Selective inhibition of ß-catenin inhibits inflammatory processes (since chemokines and pro-inflammatory cytokines are produced during Wnt activation), reduces growth of activated HSCs and reduces collagen synthesis and angiogenesis, thereby reducing the progression of liver fibrosis in vivo. While the canonical Wnt pathway is usually inactive in a physiologically healthy liver, it shows activity during cell regeneration or renewal and in certain pathophysiological conditions, such as liver diseases and cancer. Targeted blocking of some of the basic components of the Wnt pathway is a therapeutic approach. These include the frizzled transmembrane receptor (Fz) receptors using the secreted frizzled-related protein family (sFRP), Fz-coreceptors low-density LRP 5/6 through dickkopf-related protein 1 (DKK1) or niclosamide, glycogen kinase-3 beta (GSK-3β) using SB-216763, cyclic-AMP response element-binding protein (CBP) using PRI-724 and ICG-001, the lymphoid enhancer binding factor (LEF)/T cell-specific transcription factor (TCF) system as well as Wnt inhibitory factor 1 (WIF1) and miR-17-5p using pinostilbene hydrate (PSH). Significant progress has been made in inhibiting Wnt and thus stopping the progression of liver fibrosis by diminishing key components for its action. Comprehending the role of the Wnt signaling pathway in liver fibrosis may lead to discovery of novel targets in liver fibrosis therapeutic strategies' development.

Resveratrol enhanced mitochondrial recovery from cryopreservation-induced damages in oocytes and embryos

BACKGROUND

Mitochondria play a crucial role in nuclear maturation, fertilization, and subsequent embryo development. Cryopreservation is an important assisted reproductive technology that is used worldwide for humans and domestic animals. Although mitochondrial quantity and quality are decisive factors for successful development of oocytes and embryos, cryopreservation induces mitochondrial dysfunction. Upon thawing, the damaged mitochondria are removed, and de novo synthesis occurs to restore the function of mitochondria. Resveratrol, 3,5,4'-trihydroxystilbene, is a polyphenolic antioxidant that has versatile target proteins, among which sirtuin-1 (SIRT1) is a key regulator of in mitochondrial biogenesis and degradation.

METHODS

The present study is a literature review focusing on experiments involving the hypothesis that the activation of mitochondrial biogenesis and degradation following cryopreservation and warming by resveratrol may help mitochondrial recovery and improve oocyte and embryo development.

MAIN FINDINGS AND CONCLUSION

Resveratrol improves oocyte maturation and development and upregulates mitochondrial biogenesis and degradation. When vitrified-warmed embryos are treated with resveratrol, it helps in mitochondrial regulation and recovery of embryos from cryopreservation-induced damage.

CONCLUSION

Resveratrol treatment is a possible countermeasure against cryopreservation-induced mitochondrial damage.

Efficacy and Safety of Resveratrol Supplements on Blood Lipid and Blood Glucose Control in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background

Diabetes is a major public health concern. Resveratrol has shown great beneficial effects on hyperglycemia and insulin resistance and as an antioxidant.

Methods

We searched the Chinese and English databases (such as CNKI, PubMed, and Embase) and extracted data from randomized controlled trials (RCTs). Then, RevMan 5.3 was used for bias risk assessment and meta-analysis. The primary outcome indicators include insulin-resistance-related indicators and blood-lipid-related indicators. This systematic review and meta-analysis was registered in PROSPERO (CRD42018089521).

Results

Fifteen RCTs involving 896 patients were included. For insulin-resistance-related indicators, the summary results showed that, compared with the control group, homeostasis model assessment for insulin resistance (HOMA-IR) in the resveratrol group is lower (WMD: −0.99; 95% CI −1.61, −0.38; P=0.002). For blood-lipid-related indicators, the total cholesterol (TC) and triglyceride (TG) in the resveratrol group is of no statistical significance (for TC, WMD: −7.11; 95% CI −16.28, 2.06; P=0.13; for TG, WMD: −2.15; 95% CI −5.52, 1.22; P=0.21). For adverse events, the summary results showed that there was no statistical difference in the incidence of adverse events between the resveratrol and control groups (WMD: 2; 95% CI 0.44, 9.03; P=0.37).

Conclusion

Based on the current evidence, resveratrol may improve insulin resistance, lower fasting blood glucose and insulin levels, and improve oxidative stress in patients with type 2 diabetes mellitus.

Resveratrol for targeting the tumor microenvironment and its interactions with cancer cells

Tumor resistance to therapy modalities is one of the major challenges to the eradication of cancer cells and complete treatment. Tumor includes a wide range of cancer and non-cancer cells that play key roles in the proliferation of cancer cells and suppression of anti-tumor immunity. For overcoming tumor resistance to therapy, it is important to have in-depth knowledge relating to intercellular communications within the tumor microenvironment (TME). TME includes various types of immune cells such as CD4 + T lymphocytes, cytotoxic T lymphocytes (CTLs), natural killer (NK) cells, macrophages, and T regulatory cells (Tregs). Furthermore, some non-immune cells like cancer stem cells (CSCs), mesenchymal stem cells (MSCs), and cancer-associated fibroblasts (CAFs) are involved in the promotion of tumor growth. The interactions between these cells with cancer cells play a key role in tumor growth or inhibition. Resveratrol as a natural agent has shown the ability to modulate the immune system to potentiate anti-tumor immunity and also help to attenuate cancer cells and CSCs resistance. Thus, this review explains how resveratrol can modulate interactions within TME.

Genetic Toxicology and Safety Pharmacological Evaluation of Forsythin

Introduction

Forsythin is the main ingredient of Forsythia suspensa and is widely used in treatment of fever, viral cold, gonorrhea, and ulcers clinically. This study aimed to evaluate the potential genetic toxicity of forsythin and its safety for human use.

Methods

Based on the Good Laboratory Practice regulations and test guidelines, the genetic toxicity of forsythin was assessed by the Ames test, chromosome aberration (CA) test, and bone marrow micronucleus (MN) test in vivo. In the Ames test, five strains of Salmonella typhimurium were exposed to different concentrations of forsythin in the presence or absence of the S9 mixture, and then, the number of His + revertant colonies was counted. In the CA test, Chinese hamster lung (CHL) fibroblast cells were treated with different concentrations of forsythin, mitomycin C, or cyclophosphamide in the presence or absence of the S9 mixture, and the chromosomal aberrations were determined. In the MN test, bone marrow was isolated from the mice with different treatments, and the ratios of polychromatic erythrocytes (PCE) and erythrocytes (PCE/(PCE + NCE)) were measured. Finally, beagle dogs were divided into four groups (negative control, low dose, medium dose, and high dose groups), and then, a telemetry system was used to evaluate the safe use of forsythin.

Results

Ames test results showed that the number of colonies in all test strains with different treatments showed no significantly dose-dependent increase in the presence or absence of the S9 mixture (p > 0.05). In the CA test, the number of cells with aberrations in the CHL fibroblast cells treated with low, medium, and high doses of forsythin for 24/48 h in the absence of the S9 mixture was, respectively, 5.0/2.5, 4.5/1.5, and 5.0/5.0, and in the presence of the S9 mixture, the number was, respectively, 5.0, 5.0, and 4.5. These results showed that there was no significant difference compared to the negative control group either in the presence (2.0) or in the absence (4.0/2.5 for 24/48 h) of the S9 mixture (p > 0.05). The MN test showed that the values of PCE/(PCE + NCE) in the negative, positive controls, and forsythin treatment groups were all more than 20%, which indicated that forsythin had no cytotoxicity. Additionally, no significant toxicological effects of forsythin on blood pressure, respiration, temperature, electrocardiogram, and other physiological indicators in the conscious beagle dogs of different groups were observed by the telemetry method.

Conclusion

Our findings showed that forsythin has low probability of genetic toxicity and no significant toxicological effects, which implied that forsythin is suitable for further development and potential application.

Applications of Fruit Polyphenols and Their Functionalized Nanoparticles Against Foodborne Bacteria: A Mini Review

The ingestion of contaminated water and food is known to cause food illness. Moreover, on assessing the patients suffering from foodborne disease has revealed the role of microbes in such diseases. Concerning which different methods have been developed for protecting food from microbes, the treatment of food with chemicals has been reported to exhibit an unwanted organoleptic effect while also affecting the nutritional value of food. Owing to these challenges, the demand for natural food preservatives has substantially increased. Therefore, the interest of researchers and food industries has shifted towards fruit polyphenols as potent inhibitors of foodborne bacteria. Recently, numerous fruit polyphenols have been acclaimed for their ability to avert toxin production and biofilm formation. Furthermore, various studies have recommended using fruit polyphenols solely or in combination with chemical disinfectants and food preservatives. Currently, different nanoparticles have been synthesized using fruit polyphenols to curb the growth of pathogenic microbes. Hence, this review intends to summarize the current knowledge about fruit polyphenols as antibacterial agents against foodborne pathogens. Additionally, the application of different fruit extracts in synthesizing functionalized nanoparticles has also been discussed.

Resveratrol protects against cisplatin-induced ovarian and uterine toxicity in female rats by attenuating oxidative stress, inflammation and apoptosis

Cisplatin is an important antineoplastic drug used in multiple chemotherapeutic regimens but unfortunately causes serious toxic effects as ovarian and uterine toxicity. This study aimed to investigate the potential protective effect of resveratrol (RSV) against cisplatin-induced ovarian and uterine toxicity in female rats. Thirty-two female Wistar rats were divided randomly into four groups (n = 8 in each). Control group received oral normal saline for 28 days; RSV group received RSV (10 mg/kg; daily) via oral gavage; CIS group received a single dose of CIS (7 mg/kg; i.p.) on the 21st day; (CIS + RSV) group received both RSV and CIS by the same schedules and doses of RSV and CIS groups, respectively. Results demonstrated a significant decrease in MDA level and a significant increase in both glutathione content and activity of the antioxidant enzymes GPx, SOD, and CAT in the tissues of the ovary and uterus of CIS + RSV group in comparison to that of CIS group (P<0.05), also there are significantly decreased tissue levels of the proinflammatory cytokines and enzymes (NF-κB, IL-1β, IL-6, TNF-α, COX-2, and iNOS), increased estradiol, progesterone, prolactin and decreased FSH serum levels in CIS + RSV group compared to CIS group (P < 0.05). Moreover, there is downregulation of tissues Cleaved Caspase-3, NF-κB and Cox-2 proteins as shown in Western blot analysis, also apoptosis was significantly inhibited, evidenced by downregulation of Bax and upregulation of Bcl-2 proteins, and the ovarian and uterine histological architecture and integrity were maintained in CIS + RSV group compared to CIS group. In conclusion, these findings indicate that RSV has beneficial effects in ameliorating cisplatin-induced oxidative stress, inflammation, and apoptosis in the ovarian and uterine tissues of female rats.

Longevity pathways in stress resistance: targeting NAD and sirtuins to treat the pathophysiology of hemorrhagic shock

Stress resistance correlates with longevity and this pattern has been exploited to help identify genes that can influence lifespan. Reciprocally, genes and pharmacological agents that have been studied primarily in the context of longevity may be an untapped resource for treating acute stresses. Here we summarize the evidence that targeting SIRT1, studied primarily in the context of longevity, can improve outcomes in hemorrhagic shock and resuscitation. Hemorrhagic shock is a potentially fatal condition that occurs when blood loss is so severe that tissues no longer receive adequate oxygen. While stabilizing the blood pressure and reperfusing tissues are necessary, re-introducing oxygen to ischemic tissues generates a burst of reactive oxygen species that can cause secondary tissue damage. Reactive oxygen species not only exacerbate the inflammatory cascade but also can directly damage mitochondria, leading to bioenergetic failure in the affected tissues. Treatments with polyphenol resveratrol and with nicotinamide adenine dinucleotide (NAD) precursors have both shown promising results in rodent models of hemorrhagic shock and resuscitation. Although a number of different mechanisms may be at play in each case, a common theme is that resveratrol and NAD both enhance the activity of SIRT1. Moreover, many of the physiologic improvements observed with resveratrol and NAD precursors are consistent with modulation of known SIRT1 targets. Because small blood vessels and limited blood volume make mice very challenging for the development of hemorrhagic shock models, there is a paucity of direct genetic evidence testing the role of SIRT1. However, the development of more robust methods in mice as well as genetic modifications in rats should allow the study of SIRT1 transgenic and KO rodents in the near future. The potential therapeutic effect of SIRT1 in hemorrhagic shock may serve as an important example supporting the value of considering "longevity" pathways in the mitigation of acute stresses.

The relevant targets of anti-oxidative stress: a review

Previous studies have found that oxidative stress is the negative reaction of the imbalance between oxidation and antioxidation caused by free radicals, and it is the fuse of aging and many diseases. Scavenging the accumulation of free radicals in the body and inhibiting the production of free radicals are effective ways to reduce the occurrence of oxidative stress. In recent years, studies have found that oxidative stress has other effects on the body, such as anti-tumour. In this paper, the targets related to anti-oxidative stress were introduced, and they were divided into nuclear transcription factors, enzymes, solute carrier family 7, member 11 (SLC7A11) genes and iron death, ion channels, molecular chaperones, small molecules according to their different functions. In addition, we introduce the research status of agonists/inhibitors related to these targets, so as to provide some reference for the follow-up research and clinical application of anti-oxidative stress drugs.

Plant Phenolics: Bioavailability as a Key Determinant of Their Potential Health-Promoting Applications

Phenolic compounds are secondary metabolites widely spread throughout the plant kingdom that can be categorized as flavonoids and non-flavonoids. Interest in phenolic compounds has dramatically increased during the last decade due to their biological effects and promising therapeutic applications. In this review, we discuss the importance of phenolic compounds' bioavailability to accomplish their physiological functions, and highlight main factors affecting such parameter throughout metabolism of phenolics, from absorption to excretion. Besides, we give an updated overview of the health benefits of phenolic compounds, which are mainly linked to both their direct (e.g., free-radical scavenging ability) and indirect (e.g., by stimulating activity of antioxidant enzymes) antioxidant properties. Such antioxidant actions reportedly help them to prevent chronic and oxidative stress-related disorders such as cancer, cardiovascular and neurodegenerative diseases, among others. Last, we comment on development of cutting-edge delivery systems intended to improve bioavailability and enhance stability of phenolic compounds in the human body.

Resveratrol and Tumor Microenvironment: Mechanistic Basis and Therapeutic Targets

Resveratrol (3,4′,5 trihydroxystilbene) is a naturally occurring non-flavonoid polyphenol. It has various pharmacological effects including antioxidant, anti-diabetic, anti-inflammatory and anti-cancer. Many studies have given special attention to different aspects of resveratrol anti-cancer properties and proved its high efficiency in targeting multiple cancer hallmarks. Tumor microenvironment has a critical role in cancer development and progression. Tumor cells coordinate with a cast of normal cells to aid the malignant behavior of cancer. Many cancer supporting players were detected in tumor microenvironment. These players include blood and lymphatic vessels, infiltrating immune cells, stromal fibroblasts and the extracellular matrix. Targeting tumor microenvironment components is a promising strategy in cancer therapy. Resveratrol with its diverse biological activities has the capacity to target tumor microenvironment by manipulating the function of many components surrounding cancer cells. This review summarizes the targets of resveratrol in tumor microenvironment and the mechanisms involved in this targeting. Studies discussed in this review will participate in building a solid ground for researchers to have more insight into the mechanism of action of resveratrol in tumor microenvironment.

Comparative toxicokinetics of Trans-resveratrol and its major metabolites in Harlan Sprague Dawley rats and B6C3F1/N mice following oral and intravenous administration

Trans-resveratrol (RES) is a naturally occurring stilbene found in numerous plants and foods. Due to its widespread human exposure and lack of toxicity and carcinogenicity data, RES was nominated to the National Toxicology Program for testing. To aid the toxicology studies, the dose, sex, and species differences in RES toxicokinetics was investigated in Harlan Sprague Dawley rats and B6C3F1/N mice following single intravenous (IV) (10 mg/kg) or oral gavage administration (312.5, 625, and 1250 mg/kg and 625, 1250, and 2500 mg/kg in rats and mice, respectively). Following IV and gavage administration, systemic exposure of RES based on AUC was trans-resveratrol-3-O-β-D-glucuronide (R3G)> > trans-resveratrol-3-sulfate (R3S) > RES in both species. Following gavage administration Tmax_predicted values were ≤ 263 min for both species and sexes. RES elimination half-life was longer in rats than mice, and shortest in male mice. Clearance was slower in mice with no apparent sex difference in both species. In both rats and mice, following gavage administration AUC increased proportionally to the dose. After gavage administration, enterohepatic recirculation of RES was observed in both rats and mice with secondary peaks occurring around 640 min in the concentration-time profiles. RES was rapidly metabolized to R3S and R3G in both species. Extensive first pass conjugation and metabolism resulted in low levels of the parent compound RES which was confirmed by the low estimates for bioavailability. The bioavailability of RES was low, ~12-31% and ~2-6% for rats and mice, respectively, with no apparent difference between sexes.

Nanoencapsulated dietary polyphenols for cancer prevention and treatment: successes and challenges

Many dietary polyphenols have been investigated for their therapeutic potential either as single agents or in combinations. Despite the significant anticancer potential of these polyphenols in in vitro cell culture and in vivo animal models, their clinical applications have been limited because of challenges such as ineffective systemic delivery, stability and low bioavailability. Nanoencapsulation of these polyphenols could prolong circulation, improve localization, enhance efficacy and reduce the chances of multidrug resistance. This review summarized the use of various polyphenols especially epigallocatechin gallate, quercetin, curcumin and resveratrol as nanoformulations for cancer prevention and treatment. Despite some success, more research is warranted to design a nanoencapsulated combination of polyphenols, effective in in vitro, in vivo and human systems.

Potential Adverse Effects of Resveratrol: A Literature Review

Due to its health benefits, resveratrol (RE) is one of the most researched natural polyphenols. Resveratrol's health benefits were first highlighted in the early 1990s in the French paradox study, which opened extensive research activity into this compound. Ever since, several pharmacological activities including antioxidant, anti-aging, anti-inflammatory, anti-cancerous, anti-diabetic, cardioprotective, and neuroprotective properties, were attributed to RE. However, results from the available human clinical trials were controversial concerning the protective effects of RE against diseases and their sequelae. The reason for these conflicting findings is varied but differences in the characteristics of the enrolled patients, RE doses used, and duration of RE supplementation were proposed, at least in part, as possible causes. In particular, the optimal RE dosage capable of maximizing its health benefits without raising toxicity issues remains an area of extensive research. In this context, while there is a consistent body of literature on the protective effects of RE against diseases, there are relatively few reports investigating its possible toxicity. Indeed, toxicity and adverse effects were reported following consumption of RE; therefore, extensive future studies on the long-term effects, as well as the in vivo adverse effects, of RE supplementation in humans are needed. Furthermore, data on the interactions of RE when combined with other therapies are still lacking, as well as results related to its absorption and bioavailability in the human body. In this review, we collect and summarize the available literature about RE toxicity and side effects. In this process, we analyze in vitro and in vivo studies that have addressed this stilbenoid. These studies suggest that RE still has an unexplored side. Finally, we discuss the new delivery methods that are being employed to overcome the low bioavailability of RE.

Role of the PGE2 receptor in ischemia-reperfusion injury of the rat retina

Purpose

To investigate the function and expression of the PGE2 receptors EP1-4 in rat retinal ischemia-reperfusion (I/R) injury and to determine the regulatory role of resveratrol (RES) in this process.

Methods

In vitro, we stimulated primary astrocytes extracted from the optic disc of rats with epidermal growth factor (EGF) and RES, and detected the location of EP1-4 expression with immunofluorescence. The expression of antiglial fibrillary acidic protein (GFAP), EGF receptor (EGFR), inducible NOS (iNOS), and EP1-4 in astrocytes was detected with western blotting. In vivo, we established an I/R injury model and RES treatment model with Sprague-Dawley rats. Changes in the thickness of the inner retina were observed with hematoxylin and eosin (H&E) staining. EP1-4 localization in the retina was observed with immunohistochemistry. The expression of COX-2, iNOS, and EP1-4 in the control and model groups was detected with western blotting.

Results

In this study, immunofluorescence and immunohistochemistry showed that EP1-4 are expressed in astrocytes and the rat retina. EGF stimulation increased the expression of EGFR, iNOS, EP1, EP2, and EP4 in astrocytes. The expression of EP1-4 was statistically significantly increased on the third day after model induction, and EP1-4 expression decreased to normal levels on day 7. EGF and RES mediated the decrease in the expression of EP2. RES treatment significantly reduced retinal damage and RGC loss, as demonstrated by the relatively intact tissue structure on day 7 observed with H&E staining. Moreover, inflammation was associated with this I/R injury model, as demonstrated by the early induction of proinflammatory mediators, and this inflammation was significantly attenuated after RES treatment.

Conclusions

These results indicate that the COX-2/PGE2/EPs pathway is involved in retinal damage and astrocyte inflammation. In addition, the results suggest that the neuroprotective effects of RES may be associated with decreased production of inflammatory mediators. These results suggest that the PGE2 receptor may be a key factor in the treatment of neurodegenerative diseases, and that RES may be used as a possible therapeutic strategy for glaucoma.

Polyphenols from Food and Natural Products: Neuroprotection and Safety

Polyphenols are naturally occurring micronutrients that are present in many food sources. Besides being potent antioxidants, these molecules may also possess anti-inflammatory properties. Many studies have highlighted their potential role in the prevention and treatment of various pathological conditions connected to oxidative stress and inflammation (e.g., cancer, and cardiovascular and neurodegenerative disorders). Neurodegenerative diseases are globally one of the main causes of death and represent an enormous burden in terms of human suffering, social distress, and economic costs. Recent data expanded on the initial antioxidant-based mechanism of polyphenols’ action by showing that they are also able to modulate several cell-signaling pathways and mediators. The proposed benefits of polyphenols, either as protective/prophylactic substances or as therapeutic molecules, may be achieved by the consumption of a natural polyphenol-enriched diet, by their use as food supplements, or with formulations as pharmaceutical drugs/nutraceuticals. It has also been proved that the health effects of polyphenols depend on the consumed amount and their bioavailability. However, their overconsumption may raise safety concerns due to the accumulation of high levels of these molecules in the organism, particularly if we consider the loose regulatory legislation regarding the commercialization and use of food supplements. This review addresses the main beneficial effects of food polyphenols, and focuses on neuroprotection and the safety issues related to overconsumption.

Resveratrol delays postovulatory aging of mouse oocytes through activating mitophagy

Resveratrol (3,5,4'-trihydroxystilbene, RSV) is a natural potential anti-aging polyphenolic compound frequently used as a nutritional supplement against several diseases. However, the underlying mechanisms by which resveratrol regulates postovulatory aging of oocytes are still insufficiently known. In this study, we found that resveratrol could delay postovulatory aging and improve developmental competence of oocytes through activating selective mitophagy in the mouse. Resveratrol could maintain spindle morphology but it disturbed cortical granule (CG) distribution during oocyte aging. This might be due to upregulated mitophagy, since blocking mitophagy by cyclosporin A (CsA) treatment affected oocyte quality by damaging mitochondrial function and it decreased embryonic development. In addition, we also observed an involvement of FoxO3a in regulating mitophagy in aging oocytes following resveratrol treatment. Taken together, our results provide evidence that mitophagy induced by resveratrol is a potential mechanism to protect against postovulatory oocyte aging.

Dietary polyphenols as a safe and novel intervention for modulating pain associated with intervertebral disc degeneration in an in-vivo rat model

Developing effective therapies for back pain associated with intervertebral disc (IVD) degeneration is a research priority since it is a major socioeconomic burden and current conservative and surgical treatments have limited success. Polyphenols are naturally occurring compounds in plant-derived foods and beverages, and evidence suggests dietary supplementation with select polyphenol preparations can modulate diverse neurological and painful disorders. This study tested whether supplementation with a select standardized Bioactive-Dietary-Polyphenol-Preparation (BDPP) may alleviate pain symptoms associated with IVD degeneration. Painful IVD degeneration was surgically induced in skeletally-mature rats by intradiscal saline injection into three consecutive lumbar IVDs. Injured rats were given normal or BDPP-supplemented drinking water. In-vivo hindpaw mechanical allodynia and IVD height were assessed weekly for 6 weeks following injury. Spinal column, dorsal-root-ganglion (DRG) and serum were collected at 1 and 6 weeks post-operative (post-op) for analyses of IVD-related mechanical and biological pathogenic processes. Dietary BDPP significantly alleviated the typical behavioral sensitivity associated with surgical procedures and IVD degeneration, but did not modulate IVD degeneration nor changes of pro-inflammatory cytokine levels in IVD. Gene expression analyses suggested BDPP might have an immunomodulatory effect in attenuating the expression of pro-inflammatory cytokines in DRGs. This study supports the idea that dietary supplementation with BDPP has potential to alleviate IVD degeneration-related pain, and further investigations are warranted to identify the mechanisms of action of dietary BDPP.

Resveratrol Delays Retinal Ganglion Cell Loss and Attenuates Gliosis-Related Inflammation From Ischemia-Reperfusion Injury

Purpose

Resveratrol has been shown to enhance the survival of retinal ganglion cells (RGCs) following ischemia-reperfusion (I/R) injury for glaucoma. However, the precise mechanisms for resveratrol's protective effects are still unclear. The aim of this study is to determine whether resveratrol can inhibit RGC apoptosis, retinal gliosis, and inflammation, all of which are critical events in retinal degeneration following I/R injury.

Methods

Right retinal ischemia was induced in adult male Sprague Dawley rats by increasing intraocular pressure to 110 mm Hg for 60 minutes, and the left eyes maintained at normal pressure serve as the control. Intraperitoneal injection of resveratrol or control buffer was performed continuously for 3 days from pre- to post-I/R injury and the protective effects were evaluated and compared. RGCs were retrogradely labeled with Fluoro-Gold by injection into superior colliculi. Apoptosis was detected by TUNEL staining. Western blotting and immunostaining for Bax, Bcl-2, and Caspase-3 were used to explore the Bax-associated apoptotic pathway. Gliosis was assessed by western blotting and immunostaining of retinal cross sections with anti-glial fibrillary acidic protein (GFAP) antibodies.

Results

In this study, resveratrol treatment significantly reduced retinal damage and RGC loss as demonstrated by the relatively intact tissue structure in hematoxylin and eosin staining at day 7 and increased Fluoro-Gold labeling of RGCs at day 14, respectively. We found that resveratrol exhibited an anti-apoptotic effect as assessed by reduced TUNEL staining, inhibition of the early upregulated expression of the apoptosis-related protein Bax, and decreased subsequently cleaved caspase-3. However, it did not affect Bcl-2 levels. Moreover, in our I/R injury model, the combined response of reactive gliosis and related inflammation, which were demonstrated by an early induction of pro-inflammatory mediators and subsequently increased GFAP level, were significantly attenuated after resveratrol treatment.

Conclusions

These results demonstrate that resveratrol can prevent RGC death by blocking the Bax-caspase-3-dependent apoptotic pathway and suppressed gliosis-related inflammation in the retina after I/R injury. Together these results support the use of resveratrol as a possible therapeutic strategy for glaucoma.

Resveratrol and Its Effects on the Vascular System

Resveratrol, the phenolic substance isolated initially from Veratrum grandiflorum and richly present in grapes, wine, peanuts, soy, and berries, has been attracting attention of scientists and medical doctors for many decades. Herein, we review its effects on the vascular system. Studies utilizing cell cultures and pre-clinical models showed that resveratrol alleviates oxidative stress and inflammation. Furthermore, resveratrol suppresses vascular smooth muscle cell proliferation, promotes autophagy, and has been investigated in the context of vascular senescence. Pre-clinical models unambiguously demonstrated numerous vasculoprotective effects of resveratrol. In clinical trials, resveratrol moderately diminished systolic blood pressure in hypertensive patients, as well as blood glucose in patients with diabetes mellitus. Yet, open questions remain, as exemplified by a recent report which states that the intake of resveratrol might blunt certain positive effects of exercise in older persons, and further research addressing the framework for long-term use of resveratrol as a food supplement, will stay in demand.

Preventive effects of combinative natural foods produced by elite crop varieties rich in anticancer effects on N-nitrosodiethylamine-induced hepatocellular carcinoma in rats

The World Cancer Research Fund International has released 32 anticancer effects (ACEs) that targeted every stage of cancer processes. Thus, we designed two formulas of natural food combination Diet I and Diet II, mainly produced by elite crop varieties rich in ACEs with different mixture ratios, and evaluated their cancer preventive effects on N-nitrosodiethylamine (NDEA)-induced hepatocarcinogenesis. After 20 weeks of dietary intervention, Diet I and Diet II reduced incidence, size, and number of hepatic nodules (p < 0.01) and prevented hepatic tumor formation in NDEA-induced hepatocarcinogenesis rats. Low-grade hepatic dysplasia incidence was 20% for Diet II and 40% for Diet I, and apparent hepatocellular carcinomas (HCC) rates were both 0, while 90% HCC in control diet treatment group (p < 0.01). Diet I and Diet II ameliorated abnormal liver function enzymes, reduced serum alpha fetal protein, tumor-specific growth factor, dickkopf-related protein 1, tumor necrosis factor-alpha and interleukin-6 levels, regulated hepatic phase I and II xenobiotic-metabolizing enzymes, enhanced antioxidant capacity, suppressed NDEA-initiated oxidative DNA damage, and induced apoptosis coupled to down-regulation of proinflammatory, invasion, and angiogenesis markers. Daily intake of combination diet produced from ACEs-rich elite crop varieties can effectively prevent or delay occurrence and development of NDEA-induced hepatocarcinogenesis in rats.

Resveratrol: Twenty Years of Growth, Development and Controversy

Resveratrol was first isolated in 1939 by Takaoka from Veratrum grandiflorum O. Loes. Following this discovery, sporadic descriptive reports appeared in the literature. However, spurred by our seminal paper published nearly 60 years later, resveratrol became a household word and the subject of extensive investigation. Now, in addition to appearing in over 20,000 research papers, resveratrol has inspired monographs, conferences, symposia, patents, chemical derivatives, etc. In addition, dietary supplements are marketed under various tradenames. Once resveratrol was brought to the limelight, early research tended to focus on pharmacological activities related to the cardiovascular system, inflammation, and cancer but, over the years, the horizon greatly expanded. Around 130 human clinical trials have been (or are being) conducted with varying results. This may be due to factors such as disparate doses (ca. 5 to 5,000 mg/day) and variable experimental settings. Further, molecular targets are numerous and a dominant mechanism is elusive or nonexistent. In this context, the compound is overtly promiscuous. Nonetheless, since the safety profile is pristine, and use as a dietary supplement is prevalent, these features are not viewed as detrimental. Given the ongoing history of resveratrol, it is reasonable to advocate for additional development and further clinical investigation. Topical preparations seem especially promising, as do conditions that can respond to anti-inflammatory action and/or direct exposure, such as colon cancer prevention. Although the ultimate fate of resveratrol remains an open question, thus far, the compound has inspired innovative scientific concepts and enhanced public awareness of preventative health care.

Resveratrol: A miraculous natural compound for diseases treatment

Resveratrol (3, 5, 4'-trihydroxystilbene) is a nonflavonoid polyphenol that naturally occurs as phytoalexin. It is produced by plant sources such as grapes, apples, blueberries, plums, and peanut. This compound has critical roles in human health and is well known for its diverse biological activities such as antioxidant and anti-inflammatory properties. Nowadays, due to rising incidence of different diseases such as cancer and diabetes, efforts to find novel and effective disease-protective agents have led to the identification of plant-derived compounds such as resveratrol. Furthermore, several in vitro and in vivo studies have revealed the effectiveness of resveratrol in various diseases such as diabetes mellitus, cardiovascular disease, metabolic syndrome, obesity, inflammatory, neurodegenerative, and age-related diseases. This review presents an overview of currently available studies on preventive properties and essential molecular mechanisms involved in various diseases.

Resveratrol Promotes Nerve Regeneration via Activation of p300 Acetyltransferase-Mediated VEGF Signaling in a Rat Model of Sciatic Nerve Crush Injury

Peripheral nerve injuries are generally associated with incomplete restoration of motor function. The slow rate of nerve regeneration after injury may account for this. Although many benefits of resveratrol have been shown in the nervous system, it is not clear whether resveratrol could promote fast nerve regeneration and motor repair after peripheral nerve injury. This study showed that the motor deficits caused by sciatic nerve crush injury were alleviated by daily systematic resveratrol treatment within 10 days. Resveratrol increased the number of axons in the distal part of the injured nerve, indicating enhanced nerve regeneration. In the affected ventral spinal cord, resveratrol enhanced the expression of several vascular endothelial growth factor family proteins (VEGFs) and increased the phosphorylation of p300 through Akt signaling, indicating activation of p300 acetyltransferase. Inactivation of p300 acetyltransferase reversed the resveratrol-induced expression of VEGFs and motor repair in rats that had undergone sciatic nerve crush injury. The above results indicated that daily systematic resveratrol treatment promoted nerve regeneration and led to rapid motor repair. Resveratrol activated p300 acetyltransferase-mediated VEGF signaling in the affected ventral spinal cord, which may have thus contributed to the acceleration of nerve regeneration and motor repair.

Retracted Article: Resveratrol attenuates inflammation and reduces matrix-metalloprotease expression by inducing autophagy via suppressing the Wnt/β-catenin signaling pathway in IL-1β-induced osteoarthritis chondrocytes

Resveratrol (Res), a naturally occurring polyphenolic compound, has been reported to exert many biological effects like anti-inflammatory and anti-oxidant effects. In this study, we investigated the role of Res on IL-1β-induced osteoarthritis (OA) chondrocytes and its possible mechanism. Results demonstrated that Res suppressed IL-1β-induced IL-1, IL-6 and TNF-α production in a dose-dependent manner. Res also decreased MMP-1, MMP-3 and MMP-13 production in IL-1β-induced OA chondrocytes. These results suggested that Res suppressed IL-1β-induced inflammation and matrix-metalloproteases (MMP) expression in OA chondrocytes. In addition, Res was found to reverse the decreased autophagy level through increasing the expression of Beclin1, LC3 II/I ratio and LC3⁺ puncta in IL-1β-induced OA chondrocytes. Inhibition of autophagy by 3-methyladenine (3-MA) abolished the inhibitory effect of Res on inflammation and MMP expression in IL-1β-induced OA chondrocytes. Moreover, the Wnt/β-catenin signaling pathway was activated in IL-1β-induced OA chondrocytes. However, Res was found to suppress this activated Wnt/β-catenin signaling pathway. Activation of the Wnt/β-catenin signaling pathway counteracted the promoted effect on autophagy and inhibitory effect on inflammation and MMP expression of Res in IL-1β-induced OA chondrocytes. Taken together, our data demonstrated that Res attenuated inflammation and reduced MMP expression through inducing autophagy via inhibiting the Wnt/β-catenin signaling pathway in IL-1β-induced OA chondrocytes. Res may be used as a potential therapeutic agent for OA treatment.

Resveratrol (Res), a naturally occurring polyphenolic compound, has been reported to exert many biological effects like anti-inflammatory and anti-oxidant effects.

Anticancer effects of resveratrol in canine hemangiosarcoma cell lines

Hemangiosarcoma (HSA) is a highly malignant tumour with aggressive biological behaviour. HSAs are more common in dogs than other domestic animals. The median survival time of dogs with HSA remains short, even with chemotherapy and surgery. Therefore, there is a critical need to improve the adjuvant chemotherapeutic regimens to improve clinical outcomes in dogs with HSA. Resveratrol has been shown to possess strong anti-proliferative and/or pro-apoptotic properties in human cancer cell lines. Nevertheless, the potential anticancer effects of resveratrol have not been reported in canine HSAs. The objective of this study is to determine the growth inhibitory effects of resveratrol in HSA cells when used alone or in combination with doxorubicin, a commonly used chemotherapeutic agent. Frog and DD-1 canine HSA cell lines were treated with varying concentrations of resveratrol with and without doxorubicin. Cell viability was measured by the MTT assay. The expression of apoptotic proteins, activation of p38 mitogen-activated protein kinase (MAPK), AMP-activated protein kinase (AMPK) and extracellular signal-regulated kinase 1/2 (ERK1/2) were assessed by western blotting. Similar to human cancer cell lines, resveratrol markedly inhibited the growth and induced apoptosis in both HSA cell lines. Mechanistically, resveratrol activated p38 MAPK, but did not affect the AMPK or the ERK1/2 pathways. Additional experiments showed that resveratrol augmented the growth-inhibitory and apoptotic effects of doxorubicin in both HSA cell lines. These findings suggest that resveratrol has pro-apoptotic effects in canine HSA cells; therefore, its use as a potential adjunct therapy in canine HSA patients warrants further investigation.

The grapes and wrath: using resveratrol to treat the pathophysiology of hemorrhagic shock

Resveratrol, a naturally occurring polyphenol found in grapes, has been shown to reduce oxidative stress and inflammation in a variety of conditions. Recently, resveratrol has been investigated as a potential adjunct to resuscitation therapy for hemorrhagic shock-a condition characterized by tissue hypoxia, mitochondrial dysfunction, and inflammation. Although standard resuscitation restores tissue perfusion, it can exacerbate oxidative stress and organ damage. In rodent models of severe hemorrhagic shock, resveratrol mitigates reperfusion injury, preserves organ function, and improves survival. While many of these benefits can be attributed to its ability to activate sirtuin 1, resveratrol interacts with many targets that are relevant to ischemia-reperfusion. Here, we explore the probable mechanisms, potential benefits, and possible problems associated with administering resveratrol as an adjunct during resuscitation of hemorrhagic shock.

A mixed grape and blueberry extract is safe for dogs to consume

Background

Grape and blueberry extracts are known to protect against age-related cognitive decline. However, beneficial effects achieved by mixing grape and blueberry extracts have yet to be evaluated in dogs, or their bioavailability assessed. Of concern to us were cases of acute renal failure in dogs, after their ingestion of grapes or raisins. The European Pet Food Industry Federation (2013) considers only the grape or raisin itself to be potentially dangerous; grape-seed extracts per-se, are not considered to be a threat. Our aim was therefore to evaluate the renal and hepatic safety, and measure plasma derivatives of a polyphenol-rich extract from grape and blueberry (PEGB; from the Neurophenols Consortium) in dogs. Polyphenol expression was analyzed by UHPLC-MS/MS over 8 hours, for dogs given PEGB at 4 mg/kg. Safety was evaluated using four groups of 6 dogs. These groups received capsules containing no PEGB (control), or PEGB at 4, 20, or 40 mg/kg BW/d, for 24 weeks. Blood and urine samples were taken the week prior to study commencement, then at the end of the 24-wk study period. Routine markers of renal and liver damage, including creatinine (Creat), blood urea nitrogen, albumin, minerals, alkaline phosphatase (ALP), and alanine transaminase (ALT) were measured. Biomarkers for early renal damage were also evaluated in plasma (cystatin C (CysC), and neutrophil gelatinase-associated lipocalin (NGAL)), and urine (CysC, clusterin (Clu), and NGAL). Ratios of urinary biomarkers to Creat were calculated, and compared with acceptable maximal values obtained for healthy dogs, as reported in the literature.

Results

While several PEGB-specific polyphenols and metabolites were detected in dog plasma, at the end of the PEGB consumption period, our biomarker analyses presented no evidence of either renal or liver damage (Creat, BUN, ionogram, albumin and ALT, ALP). Similarly, no indication of early renal damage could be detected. Plasma CysC, urinary CysC/Creat, Clu/Creat, and NGAL/Creat ratios were all beneath reported benchmarked maximums, with no evidence of PEGB toxicity.

Conclusions

Long-term consumption of a pet specific blend of a polyphenol-rich extract from grape and blueberry (PEGB; from the Neurophenols Consortium), was not associated with renal or hepatic injury, and can therefore be considered safe.

Resveratrol protects the ovary against chromium-toxicity by enhancing endogenous antioxidant enzymes and inhibiting metabolic clearance of estradiol

Resveratrol (RVT), a polyphenolic component in grapes and red wine, has been known for its cytoprotective actions against several diseases. However, beneficial effects of RVT against early exposure to endocrine disrupting chemicals (EDCs) have not been understood. EDCs are linked to several ovarian diseases such as premature ovarian failure, polycystic ovary syndrome, early menopause and infertility in women. Hexavalent chromium (CrVI) is a heavy metal EDC, and widely used in >50 industries. Environmental contamination with CrVI in the US is rapidly increasing, predisposing the human to several illnesses including cancers and still birth. Our lab has been involved in determining the molecular mechanism of CrVI-induced female infertility and intervention strategies to mitigate CrVI effects. Lactating mother rats were exposed to CrVI (50ppm potassium dichromate) from postpartum days 1-21 through drinking water with or without RVT (10mg/kg body wt., through oral gavage daily). During this time, F1 females received respective treatments through mother's milk. On postnatal day (PND) 25, blood and the ovary, kidney and liver were collected from the F1 females for analyses. CrVI increased atresia of follicles by increasing cytochrome C and cleaved caspase-3; decreasing antiapoptotic proteins; decreasing estradiol (E2) biosynthesis and enhancing metabolic clearance of E2, increasing oxidative stress and decreasing endogenous antioxidants. RVT mitigated the effects of CrVI by upregulating cell survival proteins and AOXs; and restored E2 levels by inhibiting hydroxylation, glucuronidation and sulphation of E2. This is the first study to report the protective effects of RVT against any toxicant in the ovary.