Resveratrol and its analogs: defense against cancer, coronary disease and neurodegenerative maladies or just a fad?

Distinct Mechanisms Underlying Resveratrol-Mediated Protection from Types of Cellular Stress in C6 Glioma Cells

The polyphenolic phytostilbene, trans-resveratrol, is found in high amounts in several types and tissues of plants, including grapes, and has been proposed to have beneficial effects in the central nervous system due to its activity as an antioxidant. The objective of the present study was to identify the mechanisms underlying the protective effects of resveratrol under conditions of oxidative stress or DNA damage, induced by the extracellularly applied oxidant, tert-butyl hydrogen peroxide, or UV-irradiation, respectively. In C6 glioma cells, a model system for glial cell biology and pharmacology, resveratrol was protective against both types of insult. Prevention of tau protein cleavage and of the formation of neurofibrillary tangles were identified as mechanisms of action of resveratrol-mediated protection in both paradigms of cellular damage. However, depending on the type of insult, resveratrol exerted its protective activity differentially: under conditions of chemically induced oxidative stress, inhibition of caspase activity, while with DNA damage, resveratrol regulated tau phosphorylation at Ser⁴²². Results advance our understanding of resveratrol’s complex impact on cellular signaling pathway and contribute to the notion of resveratrol’s role as a pleiotropic therapeutic agent.

Induction of sirtuin-1 signaling by resveratrol induces human chondrosarcoma cell apoptosis and exhibits antitumor activity

Chondrosarcoma is a malignant primary bone tumor. Sirtuin-1 (SIRT1), which is a member of sirtuin family, plays a dual role either in cancer promotion or suppression. There is no report about the role of SIRT1 in the human chondrosarcoma cells. Resveratrol is a potent activator of SIRT1. However, its effects on chondrosarcoma have not been extensively studied. Here, we investigated the role of SIRT1 induction by resveratrol in human chondrosarcoma cell growth and tumor progression. Resveratrol significantly decreased cell viability and induced cell apoptosis in human chondrosarcoma cells in a dose-dependent manner. The protein expression and activity of SIRT1 were activated after treatment with resveratrol. Resveratrol significantly inhibited NF-κB signaling by deacetylating the p65 subunit of NF-κB complex, which could be reversed by siRNA-SIRT1 transfection or deacetylation inhibitor MS-275. Resveratrol induced-apoptosis involved a caspase-3-mediated mechanism. Both siRNA-SIRT1 transfection and MS-275 significantly inhibited the resveratrol-induced caspase-3 cleavage and activity in human chondrosarcoma cells. Moreover, in vivo chondrosarcoma xenograft study revealed a dramatic reduction in tumor volume and the increased SIRT1 and cleaved caspase-3 expressions in tumors by resveratrol treatment. These results suggest that resveratrol induces chondrosarcoma cell apoptosis via a SIRT1-activated NF-κB deacetylation and exhibits anti-chondrosarcoma activity in vivo.

Resveratrol (3,5,4'-trihydroxystilbene) and its properties in oral diseases

Health promotion strategies and lifestyle changes are important in disease prevention. Oral health has received a large amount of attention previously as it is a fundamental component of general health and it contributes to the quality of life. Therefore, the study of associations between diet, health and the presence of bioactive compounds in food is receiving a substantial amount of attention. In the present review the effects and targets of a natural polyohenolic stilbenoid compound; resveratrol (3,5,4'-trihydroxystilbene; RSV) is assessed, and the future prospects for RSV in promoting oral health are considered. RSV is a phytoalexin, synthesized by a wide range of plants and abundantly extracted in grape skin, it has been purported to exert a multiplicity of anti-inflammatory, anti-viral, anti-microbial, estrogenic, anticancer, cardioprotective, neuroprotective and immunomodulatory functions. In this review, following an introduction documenting the biochemistry of RSV and RSV glucosides, the bioavailability and pharmacokinetics of RSV are described. Considering its multiple properties, the present review has focused on the potential benefits of RSV as an antioxidant and chemopreventive agent.

Resveratrol Increases Serum BDNF Concentrations and Reduces Vascular Smooth Muscle Cells Contractility via a NOS-3-Independent Mechanism

Resveratrol is a polyphenol that presents both antineuroinflammatory properties and the ability to interact with NOS-3, what contributes to vasorelaxation. Brain-derived neurotrophic factor (BNDF), a molecule associated with neuroprotection in many neurodegenerative disorders, is considered as an important element of maintaining stable cerebral blood flow. Vascular smooth muscle cells (VSMCs) are considered to be an important element in the pathogenesis of neurodegeneration and a potential preventative target by agents which reduce the contractility of the vessels. Our main objectives were to define the relationship between serum and long-term oral resveratrol administration in the rat model, as well as to assess the effect of resveratrol on phenylephrine- (PHE-) induced contraction of vascular smooth muscle cells (VSMCs). Moreover, we attempt to define the dependence of contraction mechanisms on endothelial NO synthase. Experiments were performed on Wistar rats (n = 17) pretreated with resveratrol (4 weeks; 10 mg/kg p.o.) or placebo. Serum BDNF levels were quantified after 2 and 4 weeks of treatment with ELISA. Contraction force was measured on isolated and perfused tail arteries as the increase of perfusion pressure with a constant flow. Values of serum BNDF in week 0 were 1.18 ± 0.12 ng/mL (treated) and 1.17 ± 0.13 ng/mL (control) (p = ns). After 2 weeks of treatment, BDNF in the treatment group was higher than in controls, 1.52 ± 0.23 ng/mL and 1.24 ± 0.13 ng/mL, respectively. (p = 0.02) Following 4 weeks of treatment, BDNF values were higher in the resveratrol group compared to control 1.64 ± 0.31 ng/mL and 1.32 ± 0.26 ng/mL, respectively (p = 0.031). EC₅₀ values obtained for PHE in resveratrol pretreated arteries were significantly higher than controls (5.33 ± 1.7 × 10⁻⁷M/L versus 4.53 ± 1.2 × 10⁻⁸M/L, p < 0.05). These results show a significant increase in BDNF concentration in the resveratrol pretreated group. The reactivity of resistant arteries was significantly reduced for resveratrol pretreated vessels and this effect was partially NOS-3 independent.

Vincristine and ɛ-viniferine-loaded PLGA-b-PEG nanoparticles: pharmaceutical characteristics, cellular uptake and cytotoxicity

The objective of this study was to prepare the ɛ-viniferine and vincristine-loaded PLGA-b-PEG nanoparticle and to investigate advantages of these formulations on the cytotoxicity of HepG2 cells. Prepared nanoparticle has shown a homogeneous distribution with 113 ± 0.43 nm particle size and 0.323 ± 0.01 polydispersity index. Zeta potential was determined as -35.03 ± 1.0 mV. The drug-loading percentages were 6.01 ± 0.23 and 2.01 ± 0.07 for ɛ-viniferine and vincristine, respectively. The cellular uptake efficiency of coumarin-6-loaded nanoparticles was increased up to 87.8% after 4 h. Nanoparticles loaded with high concentrations of both drugs showed a cytotoxic effect on HepG2 cells, having the percentage of cell viability of between 43.23% and 47.37%. Unfortunately, the percentage of apoptotic cells after treated with drugs-loaded nanaoparticles (10.93%) was similar to free forms of drugs (12.1%) that might be due to low ɛ-viniferine release in biological pH at 24 h.

Resveratrol, Potential Therapeutic Interest in Joint Disorders: A Critical Narrative Review

Trans-resveratrol (t-Res) is a natural compound of a family of hydroxystilbenes found in a variety of spermatophyte plants. Because of its effects on lipids and arachidonic acid metabolisms, and its antioxidant activity, t-Res is considered as the major cardioprotective component of red wine, leading to the “French Paradox” health concept. In the past decade, research on the effects of resveratrol on human health has developed considerably in diverse fields such as cancer, neurodegenerative and cardiovascular diseases, and metabolic disorders. In the field of rheumatic disorders, in vitro evidence suggest anti-inflammatory, anti-catabolic, anti-apoptotic and anti-oxidative properties of t-Res in various articular cell types, including chondrocytes and synoviocytes, along with immunomodulation properties on T and B lymphocytes. In preclinical models of osteoarthritis and rheumatoid arthritis, resveratrol has shown joint protective effects, mainly mediated by decreased production of pro-inflammatory and pro-degradative soluble factors, and modulation of cellular and humoral responses. Herein, we comprehensively reviewed evidence supporting a potential therapeutic interest of t-Res in treating symptoms related to rheumatic disorders.

Anti-metastatic potential of resveratrol and its metabolites by the inhibition of epithelial-mesenchymal transition, migration, and invasion of malignant cancer cells

BACKGROUND

Increased epithelial-mesenchymal transition (EMT) and cell migration and invasion abilities of cancer cells play important roles in the metastatic process of cancer. Resveratrol is a stilbenoid, a type of natural polyphenol found in the skin of grapes, berries, and peanuts. A number of experiments have examined resveratrol's ability to target diverse pathways associated with carcinogenesis and cancer progression.

PURPOSE

This article aims to present updated overview of the knowledge that resveratrol and its metabolites or analogs have the potential to inhibit metastasis of cancer via affecting many signaling pathways related with EMT, cancer migration, and invasion in diverse organs of the body.

CHAPTERS

This article starts with a short introduction describing diverse beneficial effects of resveratrol including cancer prevention and the aim of the present study. To address the effects of resveratrol on cancer metastasis, mechanisms of EMT, migration, invasion, and their relevance with cancer metastasis, anti-metastatic effects of resveratrol through EMT-related signaling pathways and inhibitory effects of resveratrol on migration and invasion are highlighted. In addition, anti-metastatic potential of resveratrol metabolites and analogs is addressed.

CONCLUSION

Resveratrol was demonstrated to turn back the EMT process induced by diverse signaling pathways in several cellular and animal cancer models. In addition, resveratrol can exert chemopreventive efficacies on migration and invasion of cancer cells by inhibiting the related pathways and target molecules. Although these findings display the anti-metastatic potential of resveratrol, more patient-oriented clinical studies demonstrating the marked efficacies of resveratrol in humans are still needed.

Protective effect of resveratrol against nigrostriatal pathway injury in striatum via JNK pathway

Nigrostriatal pathway injury is one of the traumatic brain injury models that usually lead to neurological dysfunction or neuron necrosis. Resveratrol-induced benefits have recently been demonstrated in several models of neuronal degeneration diseases. However, the protective properties of resveratrol against neurodegeneration have not been explored definitely. Thus, we employ the nigrostriatal pathway injury model to mimic the insults on the brain. Resveratrol decreased the p-ERK expression and increased the p-JNK expression compared to the DMSO group, but not alter the p38 MAPK proteins around the lesion site by Western blot. Prior to the injury, mice were infused with resveratrol intracerebroventricularly with or without JNK-IN-8, a specific c-JNK pathway inhibitor for JNK1, JNK2 and JNK4. The study assessed modified improved neurological function score (mNSS) and beam/walking test, the level of inflammatory cytokines IL-1β, IL-6 and TNF-α, and striatal expression of Bax and Bcl-2 proteins associated with neuronal apoptosis. The results revealed that resveratrol exerted a neuroprotective effect as shown by the improved mNSS and beam latency, anti-inflammatory effects as indicated by the decreased level of IL-1β, TNF-α and IL-6. Furthermore, resveratrol up-regulated the protein expression of p-JNK and Bcl-2, down-regulated the expression of Bax and the number of Fluoro-Jade C (FJC) positive neurons. However, these advantages of resveratrol were abolished by JNK-IN-8 treatment. Overall, we demonstrated that resveratrol treatment attenuates the nigrostriatal pathway injury-induced neuronal apoptosis and inflammation via activation of c-JNK signaling.

Resveratrol counteracts lipopolysaccharide-induced depressive-like behaviors via enhanced hippocampal neurogenesis

Radial glial-like cells (RGLs) in the adult dentate gyrus (DG) function as progenitor cells for adult hippocampal neurogenesis, a process involved in the stress-related pathophysiology and treatment efficiency of depression. Resveratrol (RSV) has been demonstrated to be a potent activator of neurogenesis. The present study investigated whether chronic RSV treatment has antidepressant potential in relation to hippocampal neurogenesis. Mice received two weeks of RSV (20 mg/kg) or dimethylsulfoxide (DMSO) treatment, followed by lipopolysaccharide (LPS; 1 mg/kg) or saline injections for 5 days. We found that RSV treatment abrogated the increased immobility in the forced swimming test and tail suspension test induced by LPS. Immunohistochemical staining revealed that RSV treatment reversed the increase in microglial activation and the inhibition in DG neurogenesis. RSV treatment also attenuated LPS-induced defects in the expanding of RGLs through promoting symmetric division. In addition, RSV ameliorated LPS-induced NF-κB activation in the hippocampus coincides with the up-regulation levels of Sirt1 and Hes1. Taken together, these data indicated that RSV-induced Sirt1 activation counteracts LPS-induced depression-like behaviors via a neurogenic mechanism. A new model to understand the role of RSV in treating depression may result from these findings.

Resveratrol mitigates hepatic injury in rats by regulating oxidative stress, nuclear factor-kappa B, and apoptosis

Resveratrol is a naturally occurring polyphenol, possesses several pharmacological activities including anticancer, antioxidant, antidiabetic, antinociceptive, and antiasthmatic activity. Little is known about its hepatoprotective action mechanisms. This study was conceived to explore the possible protective mechanisms of resveratrol compared with the hepatoprotective silymarin in thioacetamide (TAA)-induced hepatic injury in rats. Thirty-two rats were equally divided into four groups; normal control (i), TAA (100 mg/kg) (ii), TAA + silymarin (50 mg/kg) (iii), and TAA + resveratrol (10 mg/kg) (iv). Liver function and histopathology, pro-inflammatory cytokines, oxidative stress, and apoptotic markers were examined. Data were analyzed using ANOVA test followed by Tukey post hoc test. Compared to TAA-intoxicated group, resveratrol mitigated liver damage, and inflammation as noted by less inflammatory infiltration, hydropic degeneration with decreased levels of tumor necrosis factor-alpha, interleukin-6, and interferon-gamma by 78.83, 18.12, and 64.49%, respectively. Furthermore, it reduced (P < 0.05) alanine and aspartate aminotransferases by 36.64 and 48.09%, respectively, restored hepatic glutathione content and normalized superoxide dismutase and malondialdehyde levels. While it inhibited nuclear factor-kappa B, cytochrome 2E1, and enhanced apoptosis of necrotic hepatocytes via increasing caspase-3 activity. Our findings indicated that the potential hepatoprotective mechanisms of resveratrol are associated with inhibition of inflammation, enhancing the apoptosis of necrotic hepatocytes, and suppression of oxidative stress.

Resveratrol improves reproductive parameters of adult rats varicocelized in peripuberty

The aim of this study was to investigate the protective action of resveratrol against the reproductive damage caused by left-sided experimental varicocele. There was a reduction of testicular major axis in the varicocele group when compared with the other groups; the testicular volume was reduced in varicocele group in comparison to the sham–control and resveratrol groups. The frequency of morphologically abnormal sperm was higher in varicocele and varicocele treated with resveratrol groups than in sham–control and resveratrol groups. The frequency of sperm with 100% of mitochondrial activity and normal acrosome integrity were lower in varicocele group than in varicocele treated with resveratrol, sham–control and resveratrol groups. Sperm motility was also reduced in varicocele group than in other groups. The sperm DNA fragmentation was higher in varicocele group than in other groups. Testicular levels of malondialdehyde were higher in varicocele and varicocele treated with resveratrol groups. The varicocele and varicocele treated with resveratrol groups had a significantly higher frequency of TUNEL-positive cells than sham–control and resveratrol groups; however, immunolabeling of the testes from varicocele treated with resveratrol group showed a lower number of apoptotic germ cells in comparison with the left testis of rats of the varicocele group. Reproductive alterations produced by varicocele from peripuberty were reduced by resveratrol in adulthood. Resveratrol should be better investigated as an adjuvant in the treatment of varicocele. Daily administration of resveratrol to rats with varicocele from peripuberty improves sperm quality in the adulthood.

Pharmacokinetics, bioavailability, metabolism and excretion of δ-viniferin in rats

A highly rapid and sensitive liquid chromatographic-electrospray ionization tandem mass spectrometric (LC-ESI-MS/MS) method was developed and validated for the determination of trans-δ-viniferin (Rs-1) in rat plasma, urine and feces. All biological samples were prepared by liquid-liquid extraction and hesperetin was included as an internal standard (IS). Chromatographic separation was achieved on a shim-pack XR-ODS column using a gradient mobile phase. MS/MS detection was performed by negative ion electrospray ionization. The method was sensitive with a lower limit of quantification of 1.42 ng/mL and linear over the range of 1.42-2172 ng/mL in all matrices. The method was applied to study the pharmacokinetics, bioavailability, metabolism, and excretion of Rs-1 in rats following a single oral or intravenous dose. Two metabolites, Rs-1 glucuronide and Rs-1 sulfate, were detected in plasma and in urine after administration of Rs-1. The absolute oral bioavailability of Rs-1 was 2.3%, and the total absorption rose to 31.5% with addition of its glucuronide and sulfate metabolites. Only 0.09% of the gavaged dose, including Rs-1 and metabolites, was excreted in the urine, while 60.3% was found in the feces in unchanged form. The results indicate that both poor absorption and extensive metabolism were the important factors that led to the poor bioavailability of Rs-1, which can provide a basis for further studies on structural modification and dosage form design.

Neuroprotective effects of resveratrol against traumatic brain injury in rats: Involvement of synaptic proteins and neuronal autophagy

Traumatic brain injury (TBI) involves primary and secondary injury cascades that underlie delayed neuronal dysfunction and death, leading to long‑term cognitive deficits, and effective therapeutic strategies targeting neuronal death remain elusive. The present study aimed to determine whether the administration of resveratrol (100 mg/kg) was able to significantly enhance functional recovery in a rat model of TBI and whether resveratrol treatment was able to upregulate synaptic protein expression and suppress post‑TBI neuronal autophagy. The results demonstrated that daily treatment with resveratrol attenuated TBI‑induced brain edema and improved spatial cognitive function and neurological impairment in rats. The expression of synaptic proteins was downregulated following TBI and this phenomenon was partly reversed by treatment with resveratrol. In addition, resveratrol was observed to significantly reduce the levels of the autophagic marker proteins, microtubule‑associated protein light chain 3‑II and Beclin1, in the hippocampus compared with the TBI group. Therefore, these results suggest that resveratrol may represent a novel therapeutic strategy for TBI, and that this protection may be associated with the upregulation of synaptophysin, postsynaptic density protein 95 and the suppression of neuronal autophagy.

Partial dealcoholization of red wine by nanofiltration and its effect on anthocyanin and resveratrol levels

The present work studies the use of nanofiltration for the production of red wine concentrate with low alcohol content. Factorial design was applied to measure the influences of transmembrane pressure (10-20 bar) and temperature (20-40 ℃) on the retention of valuable components such as anthocyanins and resveratrol, and on the nanofiltration membrane performance. The highest retention of anthocyanin and resveratrol was achieved at low temperature (20 ℃), while the high transmembrane pressure (20 bar) was found to increase the permeate flux considerably. The experiments demonstrated that nanofiltration appears as a valid technique for the production of low alcohol content red wine concentrate. Reduction of volume by a factor of 4, leads to 2.5-3 times more anthocyanins and resveratrol in the wine concentrates. The final new wine products - obtained by using various forms of reconstitution of the concentrated wine - had low alcohol content (4-6 % by volume) and their sensory attributes were similar to those of the original wine.

Genetic transformation of a fruit-specific, highly expressed stilbene synthase gene from Chinese wild Vitis quinquangularis

The stilbene synthase gene VqSTS6, from Chinese wild type Vitis quinquangularis accession Danfeng-2, increases the resveratrol content and pathogen resistance of transgenic plants of V. vinifera Thompson Seedless. This study successfully created transgenic plants of V. vinifera Thompson Seedless which overexpressed VqSTS6, cloned from Chinese wild type V. quinquangularis accession Danfeng-2. Western blot and qRT-PCR showed a variable range in transcript levels among transgenic lines. The resistance to powdery mildew (Uncinula necator) was particularly enhanced in lines most highly expressing VqSTS6. Compared with the non-transformed controls, trans-resveratrol and other stilbene compounds were significantly increased in the transgenic lines. The correlation between high resveratrol content and high pathogen resistance in transgenic grapes is discussed. We hypothesize that the fruit-specific, highly expressed gene VqSTS6 from Chinese wild V. quinquangularis accession Danfeng-2, is directly involved in the resveratrol synthesis pathway in grapes, and plays an important role in the plant's defense against pathogens. Genetic transformation of VqSTS6 explored the potential of the wild Chinese grape species for use in breeding, the results of which would raise both the disease resistance and the fruit quality of V. vinifera grapevines.

Protective effects of resveratrol on aging-induced cognitive impairment in rats

Resveratrol, a polyphenol phytoalexine, has been shown to play a neuroprotective role in the neurodegenerative process in Alzheimer's disease (AD) and improve memory function in dementia. However, the in vivo effect of resveratrol in normal aging models of learning and memory has not yet been evaluated. Therefore, the present neurobehavioral study was undertaken to evaluate the effect of resveratrol on cognitive impairment induced by aging in passive avoidance and Morris water maze (MWM) tests. Male Wistar albino rats were divided into four groups: young control (4month), young resveratrol (4month+RESV), old control (24month) and old resveratrol (24month+RESV). Resveratrol (50mg/kg/day) was given to the 4month+RESV and 24month+RESV groups orally for 12weeks. There was no significant difference between the groups for the first day of latency, while in aged rats, the second day of latency was significantly shortened compared to the young group in the passive avoidance test (p<0.05). Additionally, in the MWM test, the results showed a decrease in the time spent in the escape platform's quadrant in the probe test in aged rats (p<0.05). The administration of resveratrol at 50mg/kg/day increased the retention scores in the passive avoidance test and the time spent in the escape platform's quadrant in the MWM task (p<0.05). Furthermore resveratrol attenuated the protein levels of TNFα and IL1β in the 24-month group. These findings indicate that aging impairs emotional and spatial learning-memory and resveratrol reverses the effect of age-related learning and memory impairment. The results of this study suggest that resveratrol is effective in preventing cognitive deficit in aged rats by inhibiting the production of inflammatory cytokines.

The Potential of Plant Phenolics in Prevention and Therapy of Skin Disorders

Phenolic compounds constitute a group of secondary metabolites which have important functions in plants. Besides the beneficial effects on the plant host, phenolic metabolites (polyphenols) exhibit a series of biological properties that influence the human in a health-promoting manner. Evidence suggests that people can benefit from plant phenolics obtained either by the diet or through skin application, because they can alleviate symptoms and inhibit the development of various skin disorders. Due to their natural origin and low toxicity, phenolic compounds are a promising tool in eliminating the causes and effects of skin aging, skin diseases, and skin damage, including wounds and burns. Polyphenols also act protectively and help prevent or attenuate the progression of certain skin disorders, both embarrassing minor problems (e.g., wrinkles, acne) or serious, potentially life-threatening diseases such as cancer. This paper reviews the latest reports on the potential therapy of skin disorders through treatment with phenolic compounds, considering mostly a single specific compound or a combination of compounds in a plant extract.

Grapes (Vitis vinifera) as a Potential Candidate for the Therapy of the Metabolic Syndrome

Metabolic syndrome is associated with several disorders, including hypertension, diabetes, hyperlipidemia as well as cardiovascular diseases and stroke. Plant-derived polyphenols, compounds found in numerous plant species, play an important role as potential treatments for components of metabolic syndrome. Studies have provided evidence for protective effects of various polyphenol-rich foods against metabolic syndrome. Fruits, vegetables, cereals, nuts, and berries are rich in polyphenolic compounds. Grapes (Vitis vinifera), especially grape seeds, stand out as rich sources of polyphenol potent antioxidants and have been reported helpful for inhibiting the risk factors involved in the metabolic syndrome such as hyperlipidemia, hyperglycemia, and hypertension. There are also many studies about gastroprotective, hepatoprotective, and anti-obesity effects of grape polyphenolic compounds especially proanthocyanidins in the literature. The present study investigates the protective effects of grape seeds in metabolic syndrome. The results of this study show that grape polyphenols have significant effects on the level of blood glucose, lipid profile, blood pressure, as well as beneficial activities in liver and heart with various mechanisms. In addition, the pharmacokinetics of grape polyphenols is discussed. More detailed mechanistic investigations and phytochemical studies for finding the exact bioactive component(s) and molecular signaling pathways are suggested.

Resveratrol and liver: A systematic review

Background:

Recent studies demonstrated that resveratrol has many therapeutic effects on liver disorders. Resveratrol significantly increased survival after liver transplantation, decreased fat deposition, necrosis, and apoptosis which induced by ischemia in Wistar rats. It provided liver protection against chemical, cholestatic, and alcohol injury. Resveratrol can improve glucose metabolism and lipid profile and decrease liver fibrosis and steatosis. Furthermore, it was able to alter hepatic cell fatty acid composition. According to extension of liver disease around the world and necessity of finding new threat, this review critically examines the current preclinical in vitro and in vivo studies on the preventive and therapeutic effects of resveratrol in liver disorders.

Materials and Methods:

A search in PubMed, Google Scholar, and Scopus was undertaken to identify relevant literature using search terms, including “liver,” “hepatic,” and “Resveratrol.” Both in vivo and in vitro studies were included. No time limiting considered for this search.

Results:

A total of 76 articles were eligible for this review. In these articles, resveratrol shows antioxidative properties in different models of hepatitis resulting in reducing of hepatic fibrosis.

Conclusion:

Resveratrol could reduce hepatic steatosis through modulating the insulin resistance and lipid profile in animals. These high quality preclinical studies propose the potential therapeutic implication of resveratrol in liver disorders especially those with hepatic steatosis. Resveratrol can play a pivotal role in prevention and treatment of liver disorders by reducing hepatic fibrosis.

Upregulation of miR-328 and inhibition of CREB-DNA-binding activity are critical for resveratrol-mediated suppression of matrix metalloproteinase-2 and subsequent metastatic ability in human osteosarcomas

Osteosarcomas, the most common malignant bone tumors, show a potent capacity for local invasion and pulmonary metastasis. Resveratrol (RESV), a phytochemical, exhibits multiple tumor-suppressing activities and has been tested in clinical trials. However, the antitumor activities of RESV in osteosarcomas are not yet completely defined. In osteosarcoma cells, we found that RESV inhibited the migration/invasion in vitro and lung metastasis in vivo by suppressing matrix metalloproteinase (MMP)-2. We identified that RESV exhibited a transcriptional inhibitory effect on MMP-2 through reducing CREB-DNA-binding activity. Moreover, a microRNA (miR) analysis showed that miR-328 was predominantly upregulated after RESV treatment. Inhibition of miR-328 significantly relieved MMP-2 and motility suppression imposed by RESV treatment. Furthermore, ectopic miR-328 expression in highly invasive cells decreased MMP-2 expression and invasive abilities. Mechanistic investigations found that JNK and p38 MAPK signaling pathways were involved in RESV-regulated CREB-DNA-binding activity, miR328 expression, and cell motility. Clinical samples indicated inverse expression between MMP-2 and miR-328 in normal bone and osteosarcoma tissues. The inverse correlation of MMP-2 and miR-328 was also observed in tumor specimens, and MMP-2 expression was linked to tumor metastasis. Taken together, our results provide new insights into the role of RESV-induced molecular and epigenetic regulation in suppressing tumor metastasis.

Resveratrol Protects against Helicobacter pylori-Associated Gastritis by Combating Oxidative Stress

Helicobacter pylori (H. pylori)-induced oxidative stress has been shown to play a very important role in the inflammation of the gastric mucosa and increases the risk of developing gastric cancer. Resveratrol has many biological functions and activities, including antioxidant and anti-inflammatory effect. The purpose of this study was to probe whether resveratrol inhibits H. pylori-induced gastric inflammation and to elucidate the underlying mechanisms of any effect in mice. A mouse model of H. pylori infection was established via oral inoculation with H. pylori. After one week, mice were administered resveratrol (100 mg/kg body weight/day) orally for six weeks. The mRNA and protein levels of iNOS and IL-8 were assessed using RT-PCR, Western blot and ELISA. The expression levels of IκBα and phosphorylated IκBα (which embodies the level and activation of NF-κB), Heme Oxygenase-1 (HO-1; a potent antioxidant enzyme) and nuclear factor-erythroid 2 related factor 2 (Nrf2) were determined using Western blot, and lipid peroxide (LPO) level and myeloperoxidase (MPO) activity were examined using an MPO colorimetric activity assay, thiobarbituric acid reaction, and histological-grade using HE staining of the gastric mucosa. The results showed that resveratrol improved the histological infiltration score and decreased LPO level and MPO activity in the gastric mucosa. Resveratrol down-regulated the H. pylori-induced mRNA transcription and protein expression levels of IL-8 and iNOS, suppressed H. pylori-induced phosphorylation of IκBα, and increased the levels of HO-1 and Nrf2. In conclusion, resveratrol treatment exerted significant effects against oxidative stress and inflammation in H. pylori-infected mucosa through the suppression of IL-8, iNOS, and NF-κB, and moreover through the activation of the Nrf2/HO-1 pathway.

Biocompatible and biodegradable nanoparticles for enhancement of anti-cancer activities of phytochemicals

Many phytochemicals show promise in cancer prevention and treatment, but their low aqueous solubility, poor stability, unfavorable bioavailability, and low target specificity make administering them at therapeutic doses unrealistic. This is particularly true for (-)-epigallocatechin gallate, curcumin, quercetin, resveratrol, and genistein. There is an increasing interest in developing novel delivery strategies for these natural products. Liposomes, micelles, nanoemulsions, solid lipid nanoparticles, nanostructured lipid carriers and poly (lactide-co-glycolide) nanoparticles are biocompatible and biodegradable nanoparticles. Those nanoparticles can increase the stability and solubility of phytochemicals, exhibit a sustained release property, enhance their absorption and bioavailability, protect them from premature enzymatic degradation or metabolism, prolong their circulation time, improve their target specificity to cancer cells or tumors via passive or targeted delivery, lower toxicity or side-effects to normal cells or tissues through preventing them from prematurely interacting with the biological environment, and enhance anti-cancer activities. Nanotechnology opens a door for developing phytochemical-loaded nanoparticles for prevention and treatment of cancer.

Analysis of trans-2,6-difluoro-4'-(N,N-dimethylamino)stilbene (DFS) in biological samples by liquid chromatography-tandem mass spectrometry: metabolite identification and pharmacokinetics

The metabolism of a promising antineoplastic agent, trans-2,6-difluoro-4'-(N,N-dimethylamino)stilbene (DFS), was studied in mouse, rat, and human liver microsomes using liquid chromatography-tandem mass spectrometry (LC-MS/MS) with the multiple reaction monitoring-information-dependent acquisition-enhanced product ion scan (MRM-IDA-EPI) method. Ten putative metabolites were identified and the structures of four metabolites were confirmed using authentic standards. Since trans-2,6-difluoro-4'-(N-methylamino)stilbene (DMDFS, M1) was present in all species as metabolite and displayed in vitro growth inhibition superior to DFS, its pharmacokinetic profiles were examined in Sprague-Dawley rats using DFS as a comparator. A reliable LC-MS/MS multiple reaction monitoring (MRM) method was subsequently developed and validated for the simultaneous quantification of both DFS and DMDFS in rat plasma for this purpose. Upon intravenous administration (4 mg/kg), DFS had a moderate clearance (Cl = 62.7 ± 23.2 mL/min/kg), terminal elimination half-life (t 1/2 λZ  = 299 ± 73 min), and mean transit time (MTT = 123 ± 14 min) with demethylation metabolism accounting for about 10 % of its total clearance. DMDFS possessed an intravenous pharmacokinetic profile similar to DFS. During oral dosing (10 mg/kg) where both DFS and DMDFS were absorbed rapidly, the oral bioavailability of DFS was approximately 2-fold greater than that of DMDFS (DFS: F = 42.1 ± 12.8 %; DMDFS: F = 18.7 ± 3.9 %). Interestingly, the DMDFS exposure after oral dosing of DFS (10 mg/kg) was comparable to that after oral administration of DMDFS (10 mg/kg) alone. As DFS displayed potent anticancer activities and excellent pharmacokinetic profiles, it appears to be a favorable candidate for further pharmaceutical development.

Bioavailability of dietary polyphenols: Factors contributing to their clinical application in CNS diseases

The anatomical location of the central nervous system (CNS) renders it immunologically and pharmacologically privileged due to the blood brain barrier (BBB). Although this limits the transport of unfavorable molecules to the CNS, the ensuing privilege could be disadvantageous for therapeutic compounds. Hence, the greatest challenge in the pharmacotherapy of CNS diseases is to ensure efficient brain targeting and drug delivery. Research evidences indicate that dietary polyphenols have neuroprotective potential against CNS diseases. However, their selective permeability across BBB, poor absorption, rapid metabolism and systemic elimination limit their bioavailability and therapeutic efficacy. Consequently, the beneficial effects of these orally administered agents in the CNS still remain a subject of debate. This has also limited its clinical application either as independent or adjunctive therapy. Improving the in vivo bioavailability by novel methods could improve the therapeutic feasibility of polyphenols and assist in evolving novel drugs and their derivatives with improved efficacy in vivo. Here we review the mechanistic and pharmacological issues related to the bioavailability of polyphenols with therapeutic implications for CNS diseases. We surmise that improving the bioavailability of polyphenols entails efficient in vivo transport across BBB, biochemical stability, improved half-life and persistent neuroprotection in the CNS.

Antigenotoxic effects of resveratrol: assessment of in vitro and in vivo response

Experiments were performed to evaluate the in vitro and in vivo dose response for antigenotoxic effects of resveratrol (RES). For the in vitro study, HL-60 cells were co-treated with the test genotoxin and three concentrations of RES. Thereafter, genotoxic effects were assessed in the cytokinesis-block micronucleus test. Results of the in vitro experiments using genotoxins nitroquinoline-1-oxide (NQO) and mitomycin C (MMC) showed maximum inhibition of genotoxicity with the lowest test concentration of RES. The mouse bone marrow micronucleus assay was used for evaluating the in vivo antigenotoxic effects of RES against genotoxins diepoxybutane (DEB), MMC, methyl methanesulfonate and procarbazine (PCB). The experimental animals received RES pre-treatment by gavage 30min, 24 and 48h before injecting the genotoxin intraperitoneally. The in vivo studies demonstrated efficacy of the lowest test dose of RES for exerting maximum protection against chromosomal damage induced by all four genotoxins. The antigenotoxic effect observed with 6.25mg/kg RES was significantly higher than that of 100mg/kg RES against PCB and DEB. In conclusion, the findings from the present study indicate that lower test concentrations/doses of RES are more effective in exerting antigenotoxic effects.

Synthesis of Stilbene Derivatives: A Comparative Study of their Antioxidant Activities

A series of structurally simple compounds belonging to thestilbene family were synthesized by means of a Ti(III)-mediated methodology that allows access, in an efficient manner, to derivatives of dihydrostilbene, E-stilbene, and stilbene oxide, with high yields. The antioxidant activity of these compounds has been evaluated by means of two electrochemical assays, which provide complementary information, showing that the majority of these stilbene analogs exhibit significant antioxidant activity dependent on the electronic structure and functionalization of the molecule in each case.

The Protective Effect of Resveratrol on Concanavalin-A-Induced Acute Hepatic Injury in Mice

Pharmacologic Relevance. Resveratrol, an antioxidant derived from grapes, has been reported to modulate the inflammatory process. In this study, we investigated the effects of resveratrol and its mechanism of protection on concanavalin-A- (ConA-) induced liver injury in mice. Materials and Methods. Acute autoimmune hepatitis was induced by ConA (20 mg/kg) in Balb/C mice; mice were treated with resveratrol (10, 20, and 30 mg/kg) daily by oral gavage for fourteen days prior to a single intravenous injection of ConA. Eight hours after injection, histologic grading, proinflammatory cytokine levels, and hedgehog pathway activity were determined. Results. After ConA injection, the cytokines IL-2, IL-6, and TNF-α were increased, and Sonic hedgehog (Shh), Glioblastoma- (Gli-) 1, and Patched (Ptc) levels significantly increased. Pretreatment with resveratrol ameliorated the pathologic effects of ConA-induced autoimmune hepatitis and significantly inhibited IL-2, IL-6, TNF-α, Shh, Gli-1, and Ptc. The effects of resveratrol on the hedgehog pathway were studied by western blotting and immunohistochemistry. Resveratrol decreased Shh expression, possibly by inhibiting Shh expression in order to reduce Gli-1 and Ptc expression. Conclusion. Resveratrol protects against ConA-induced autoimmune hepatitis by decreasing cytokines expression in mice. The decreases seen in Gli-1 and Ptc may correlate with the amelioration of hedgehog pathway activity.

Anti-inflammatory effect of resveratrol in old mice liver

Inflammation is a hallmark of aging. Caloric restriction and resveratrol (RSV) have shown important effects on prevention of oxidative stress and inflammation. Here, we investigate the progression of proinflammatory markers in liver during aging and the effect of RSV on inflammation markers in the liver of old male C57BL/6J mice. Young (2 months), mature (12 months) and old (18 months) mice were fed during 6 months with RSV. Levels of IL-1β, IL-6, IL-10, IL-17 and TNF-α were evaluated by ELISA in mice liver. Levels of pro-inflammatory cytokines, IL-1β, IL-6, IL-17 and TNF-α and also their respective mRNA increased in the liver from old mice. However, RSV decreased these levels in the case of IL-1β and TNF-α but only in old mice showing no effect on young and mature animals. This reduction was also found at the mRNA level. Levels of mRNA of the components of NALP-3 inflammasome, ASC, CASP-1, NALP-1 and NALP-3, also showed an age-dependent increase that was reversed by RSV. Furthermore, cyclooxygenase 2 levels, a marker of proinflammatory innate immune activity, were also upregulated in aged liver and reversed again by RSV. In conclusion, our study confirms that aging is accompanied by an increase in the proinflammatory pattern in the liver and that RSV reduces this pattern in old mice liver.

Effect of resveratrol on behavioral performance of streptozotocin-induced diabetic mice in anxiety tests

The aim of this study was to evaluate with anxiety tests the effect of resveratrol (RSV) on streptozotocin (STZ)-induced diabetic mouse behavioral performance at the second and fourth week of treatment. Confirmed diabetic mice (>250 mg/dl of glucose in blood after STZ injection) were treated with RSV (RDM, n=12) or control treated (DM, n=12) for 4 weeks. DM and RDM were tested in the Open Field Test (OFT) and Elevated Plus Maze (EPM). In the second week of RSV treatment, a higher grooming frequency (P<0.05) and a lower defecation and rearing frequency (P<0.05) were detected in the OFT in the RDM group compared with the DM. There was a higher grooming frequency (P<0.05) and higher percentage of entries in open arms (P<0.05) in the RDM group than in the DM group in the EPM. However, in the fourth week of RSV treatment, the only effect observed was a higher grooming frequency in the RDM group than in the DM group (P<0.05) in the EPM. In conclusion, RSV treatment in diabetic mice provoked anxiolytic-like effects in both tests (OFT and EPM), and these effects were observed in a short time window (2 weeks). It is suggested that RSV may help diabetic animals to adapt to new stressing and anxiety situations and thus to improve their welfare.

Resveratrol Represses Pokemon Expression in Human Glioma Cells

POK erythroid myeloid ontogenic factor (Pokemon), an important proto-oncoprotein, is a transcriptional repressor that regulates the expression of many genes and plays an important role in tumorigenesis. Resveratrol (RSV), a natural polyphenolic compound, has many beneficial biological effects on health. In this study, we investigated the role of Pokemon in RSV-induced biological effects and the effect of RSV on the expression of Pokemon in glioma cells. We found that overexpression of Pokemon decreased RSV-induced cell apoptosis, senescence, and anti-proliferative effects. Moreover, we showed that RSV could efficiently decrease the activity of the Pokemon promoter and the expression of Pokemon. Meanwhile, RSV also inhibited Sp1 DNA binding activity to the Pokemon promoter; whereas, it did not influence the expression and nuclear translocation of Sp1. In addition, we found that RSV could increase the recruitment of HDAC1, but decreased p300 to the Pokemon promoter. Taken together, all these results extended our understanding on the anti-cancer mechanism of RSV in glioma cells.

Natural polyphenols and spinal cord injury

Polyphenols have been shown to have some of the neuroprotective effects against neurodegenerative diseases. These effects are attributed to a variety of biological activities, including free radical scavenging/antioxidant and anti-inflammatory and anti-apoptotic activities. In this regard, many efforts have been made to study the effects of various well-known dietary polyphenols on spinal cord injury (SCI) and to explore the mechanisms behind the neuroprotective effects. The aim of this paper is to present the mechanisms of neuroprotection of natural polyphenols used in animal models of SCI.

Sulfamethoxazole-trimethoprim associated with resveratrol for the treatment of toxoplasmosis in mice: Influence on the activity of enzymes involved in brain neurotransmission

This study aimed to investigate the influence of sulfamethoxazole-trimethoprim (ST) associated with resveratrol on the enzymatic activities of acetylcholinesterase (AChE), adenylate kinase (AK), pyruvate kinase (PK), and creatine kinase (CK) in the brain of mice experimentally infected by Toxoplasma gondii. For that, 60 mice were divided into ten groups with 6 animals each: groups A to D composed by healthy mice and groups E to J consisting of animals infected by T. gondii (VEG strain). Animals started treatment 20 days post-infection for 10 consecutive days with oral doses of 0.5 mg kg(-1) of ST (groups B and F), 100 mg kg(-1) of free resveratrol (groups C and G) and inclusion complex of resveratrol (nanoparticles containing resveratrol) (groups D and H), as well as with an association of both drugs (groups I and J). The results showed increased (P < 0.001) AChE activity on infected animals (groups E-J) when compared to not-infected (A) animals, and also uninfected animals treated with ST (group B) had increased AChE activity. AK activity decreased (P < 0.001) in the infected and untreated (group E), differently from the other groups that did not differ. PK activity did not differ between groups (P > 0.05). When comparing control groups (uninfected (A) and infected (E)), we verified a significant (P < 0.001) increase in CK activity in the brain, and it is noteworthy that the animals treated with resveratrol associated with ST (group I and J) had similar CK activity to those animals from the group A. Treatment with the combination of ST and resveratrol was able to reduce (P < 0.05) the number of parasitic cysts in the brain, thus reduced inflammatory infiltrates in the liver, and prevented the occurrence of hepatocytes lesions due to toxoplasmosis in mice. Based on these results, it is possible to conclude that increased AChE and CK activities after T. gondii infection did not change with the treatment of ST-resveratrol association. In addition, decreased AK activity caused by T. gondii infection was normalized by ST-resveratrol treatment. T. gondii infection and treatment does not affect PK activity in brain.

Theoretical study of complexation of resveratrol with cyclodextrins and cucurbiturils: structure and antioxidative activity

The inclusion complexation of resveratrol with cyclodextrins and cucurbiturils and the influence of complexation on the antioxidative activity of resveratrol have been theoretically studied.