Resveratrol protects against 4-hydroxynonenal-induced apoptosis by blocking JNK and c-JUN/AP-1 signaling

Biochemical Investigation of Therapeutic Potential of Resveratrol Against Arsenic Intoxication

Arsenic has been reported to cause damaging effects on different body organs. This study was designed to evaluate the protective effect of resveratrol (RSV) against arsenic trioxide (ATO)–induced intoxication in experimental animals. Twenty-four Wistar rats were allocated in 4 groups: group 1: control group, received normal diet; group 2: received ATO (3 mg/kg); group 3: received RSV (8 mg/kg) 30 minutes before administration of ATO; and group 4: received ascorbic acid (25 mg/kg) 30 minutes before administration of ATO. Treatments were given to experimental rats daily for consecutive 8 days. At the end of experimental period, bioaccumulation of arsenic in liver and kidney was assessed by hydride generation-atomic absorption spectrophotometer to investigate the association of arsenic accumulation with histological aberrations. Following parameters were also investigated: serum biochemical profile (alanine aminotransferase, aspartate transaminase, alkaline phosphatase, blood urea nitrogen, and creatinine) for evaluation of liver and kidney functions and lipid peroxidation and oxidative stress (malondialdehyde, glutathione, superoxide dismutase, catalase, and glutathione peroxidase) in tissue homogenates of liver and kidney for estimation of oxidative status. The findings of this study indicate that RSV remarkably ameliorated the hepatic and renal toxicity in arsenic-exposed rat model due to its strong antioxidant potential.

Mechanisms of deoxynivalenol-induced endocytosis and degradation of tight junction proteins in jejunal IPEC-J2 cells involve selective activation of the MAPK pathways

Mycotoxin contamination in foods is a major risk factor for human and animal health due to its prevalence in cereals and their by-products. Deoxynivalenol (DON), mainly produced by Fusarium genera, is the most common mycotoxin detected in cereal products. Deoxynivalenol disrupts intestinal barrier function and decreases protein levels of tight junction proteins (TJP). However, the overall mechanism by which DON regulates specific TJP turnover and epithelial cell integrity remains unclear. Herein, we show that DON (2 μM) decreases the protein stability and accelerates the degradation of TJP in the lysosome. Interestingly, pretreatment of cells with dynasore (a dynamin-dependent endocytosis inhibitor) protected against DON-induced degradation of claudin-3 and 4. Immunofluorescence analysis also shows that the decreased membrane presence of claudin-4 and ZO-1 induced by DON is reversible with dynamin inhibition, whereas the pretreatment with cytochalasin D (an actin-dependent endocytosis inhibitor) reverses the degradation of claudin-1 and 4 induced by DON. We also show that the endocytosis and degradation of claudin-1 is regulated by p38 mitogen-activated protein kinase (MAPK), whereas the endocytosis of claudin-4 and ZO-1 is mediated by c-Jun-N-terminal kinase (JNK). Resveratrol, with JNK inhibitory activity, also prevents the endocytosis and degradation of claudin-4 and ZO-1 and protects against DON-induced decrease in transepithelial electrical resistance (TEER) and increase in FITC-dextran permeability. Collectively, this study, for the first time, shows that DON accelerates the endocytosis and degradation of TJP and this is regulated by the activation of p38 MAPK and JNK signaling pathways. Therefore, natural bioactive compounds with p38 MAPK and JNK inhibitory activities may be effective in preventing the DON-induced TJP disruption and preserve gut barrier function in vivo.

Neuroprotective Effects of Withania somnifera on 4-Hydroxynonenal Induced Cell Death in Human Neuroblastoma SH-SY5Y Cells Through ROS Inhibition and Apoptotic Mitochondrial Pathway

The antioxidant, anti-inflammatory, and anticancer activities of Withania somnifera (WS) are known for a long time. This study was aimed to examine whether WS also diminishes 4-hydroxy-trans-2-nonenal (HNE)-induced neurotoxicity in human neuroblastoma (SH-SY5Y) cell line. The cytotoxic response of HNE (0.1-50 μM) and WS (6.25-200 μg/ml) was measured by MTT assay after exposing SH-SY5Y cells for 24 h. Then neuroprotective potential was assessed by exposing the cells to biologically safe concentrations of WS (12.5, 25, and 50 μg/ml) then HNE (50 μM). Results showed a concentration-dependent protective effect of WS at 12.5, 25, and 50 μg/ml against HNE (50 μM) induced cytotoxicity and cell inhibition. Pre-exposure to WS resulted in a strong inhibition of 24, 55 and 83% in malondialdehyde (MDA) level; 5, 27 and 60% in glutathione (GSH) level; 12, 36 and 68% in catalase activity; 11, 33 and 67% in LDH leakage; and 40, 80 and 120% in cellular LDH activity at 12.5, 25, and 50 μg/ml, respectively, induced by 50 μM HNE in SH-SY5Y cells. The HNE-mediated cellular changes (cell shrinkage, rounded bodies, and inhibition of outgrowth) and increased caspase-3 activity were also prevented by WS. The HNE-induced upregulation of proapoptotic markers (p53, caspase-3, and -9, and Bax) and downregulation of antiapoptotic marker Bcl-2 genes were also blocked by pretreatment with WS. Altogether, our findings indicate that WS possesses a protective potential against HNE-induced neurotoxicity.

The therapeutic effect of resveratrol: Focusing on the Nrf2 signaling pathway

Resveratrol is a natural polyphenol derived from grapes, berries, red wine, peanuts amongst other fruits and nuts. Beneficial effects such as anti-inflammatory, antioxidant, hepatoprotective, neuroprotective, cardioprotective, renoprotective, anti-obesity, anti-diabetic, and anti-cancer of resveratrol have been demonstrated by preclinical and clinical research. A possibility is that these therapeutical effects are associated with modulation of the Nrf2 signaling pathway in the following way: resveratrol may potentiate Nrf2 signaling through blockage of Keap1, by means of changing the Nrf2 mediators, its expression and its nuclear translocation. This article reviews the evidence of the Nrf2 modulating hypothesis as a possible molecular mechanism underlying the medicinal properties of resveratrol.

Resveratrol attenuates diabetes-associated cell centrosome amplification via inhibiting the PKCα-p38 to c-myc/c-jun pathway

Type 2 diabetes increases the risk for cancer. Centrosome amplification can initiate tumorigenesis. We have described that type 2 diabetes increases the centrosome amplification of peripheral blood mononuclear cells, with high glucose, insulin, and palmitic acid as the triggers, which suggests that centrosome amplification is a candidate biological mechanism linking diabetes to cancer. In this study, we aimed to further investigate the signaling pathways of the diabetes-associated centrosome amplification and to examine whether and how resveratrol inhibits the centrosome amplification. The results showed that treatment with high glucose, insulin, and palmitic acid, alone or in combination, could increase the protein levels of phospho-protein kinase C alpha (p-PKCα), phospho-p38 mitogen-activated protein kinases (p-p38), c-myc, and c-jun, as well as the mRNA levels of c-myc and c-jun. PKCα inhibitor could inhibit the treatment-induced increase in the protein levels of p-p38, c-myc, and c-jun. Inhibitor or siRNA of p38 was also able to inhibit the treatment-induced increase in the levels of p-p38, c-myc, and c-jun. Meanwhile, knockdown of c-myc or c-jun did not alter the treatment-induced increase in the phosphorylation of PKCα or p38. Importantly, inhibition of the phosphorylation of PKCα or p38 and knockdown of c-myc or c-jun could attenuate the centrosome amplification. In diabetic mice, the levels of p-PKCα, p-p38, c-myc, and c-jun were all increased in the colon tissues. Interestingly, resveratrol, but not metformin, was able to attenuate the treatment-induced increase in the levels of p-PKCα, p-p38, c-myc, and c-jun, as well as the centrosome amplification. In conclusion, our results suggest that PKCα-p38 to c-myc/c-jun is the signaling pathway of the diabetes-associated centrosome amplification, and resveratrol attenuates the centrosome amplification by inhibiting this signaling pathway.

Modulation of Skin Inflammatory Response by Active Components of Silymarin

In this study, we compared selected silymarin components, such as quercetin (QE), 2,3-dehydrosilybin (DHS) and silybin (SB), with the anti-inflammatory drug indomethacin (IND) in terms of their wound healing potential. In view of the fact that pathological cutaneous wound healing is associated with persistent inflammation, we studied their anti-inflammatory activity against inflammation induced by bacterial lipopolysaccharide (LPS). We investigated the regulation of crucial pro-inflammatory transcription factors—nuclear factor kappa-B (NF-κB) and activator protein 1 (AP-1)—as well as the expression of downstream inflammatory targets by Western blotting, real-time PCR (RT-PCR), electrophoretic mobility shift assay (EMSA), and/or enzyme-linked immunosorbent assay (ELISA) in vitro using primary normal human dermal fibroblasts (NHDF). We demonstrated the greater ability of DHS to modulate the pro-inflammatory cytokines production via the NF-κB and AP-1 signaling pathways when compared to other tested substances. The prolonged exposure of LPS-challenged human dermal fibroblasts to DHS had both beneficial and detrimental consequences. DHS diminished interleukin-6 (IL-6) and interleukin-8 (IL-8) secretion but induced the significant upregulation of IL-8 mRNA associated with NF-κB and AP-1 activation. The observed conflicting results may compromise the main expected benefit, which is the acceleration of the healing of the wound via a diminished inflammation.

4-Hydroxynonenal-induced GPR109A (HCA2 receptor) activation elicits bipolar responses, Gαi -mediated anti-inflammatory effects and Gβγ -mediated cell death

BACKGROUND AND PURPOSE

In this study, we examined the possibility that 4-hydroxynonenal (4-HNE) acting as a ligand for the HCA₂ receptor (GPR109A) elicits both anti-inflammatory and cell death responses.

EXPERIMENTAL APPROACH

Agonistic activity of 4-HNE was determined by observing the inhibition of cAMP generation in CHO-K1-GPR109A-G_i cell line, using surface plasmon resonance (SPR) binding and competition binding assays with [³ H]-niacin. 4-HNE-mediated signalling pathways and cellular responses were investigated in cells expressing GPR109A and those not expressing these receptors.

KEY RESULTS

Agonistic activity of 4-HNE was stronger than that of niacin or 3-OHBA at inhibiting forskolin-induced cAMP production and SPR binding affinity. In ARPE-19 and CCD-841 cells, activation of GPR109A by high concentrations of the agonists 4-HNE (≥10 μM), niacin (≥1000 μM) and 3-OHBA (≥1000 μM) induced apoptosis accompanied by elevated Ca²⁺ and superoxide levels. This 4-HNE-induced cell death was blocked by knockdown of GPR109A or NOX4 genes, or treatment with chemical inhibitors of G_βγ (gallein), intracellular Ca²⁺ (BAPTA-AM), NOX4 (VAS2870) and JNK (SP600125), but not by the cAMP analogue 8-CPT-cAMP. By contrast, low concentrations of 4-HNE, niacin and 3-OHBA down-regulated the expression of pro-inflammatory cytokines IL-6 and IL-8. These 4-HNE-induced inhibitory effects were blocked by a cAMP analogue but not by inhibitors of G_βγ -downstream signalling molecules.

CONCLUSIONS AND IMPLICATIONS

These results revealed that 4-HNE is a strong agonist for GPR109A that induces G_αi -dependent anti-inflammatory and G_βγ -dependent cell death responses. Moreover, the findings indicate that specific intracellular signalling molecules, but not GPR109A, can serve as therapeutic targets to block 4-HNE-induced cell death.

Cyanidin-3-glucoside Alleviates 4-Hydroxyhexenal-Induced NLRP3 Inflammasome Activation via JNK-c-Jun/AP-1 Pathway in Human Retinal Pigment Epithelial Cells

Recently, the NLRP3 inflammasome activation in the eyes has been known to be associated with the pathogenesis of age-related macular degeneration. The aim of this study was to investigate the protective effects of cyanidin-3-glucoside (C3G), an important anthocyanin with great potential for preventing eye diseases, against 4-hydroxyhexenal- (HHE-) induced inflammatory damages in human retinal pigment epithelial cells, ARPE-19. We noticed that C3G pretreatment to the ARPE-19 cells rescued HHE-induced antiproliferative effects. Cell apoptosis ratio induced by HHE was also decreased by C3G, measured by flow cytometry. The activation of NLRP3 inflammasome induced by HHE was found with increases of caspase-1 activity, proinflammatory cytokine releases (IL-1β and IL-18), and NLRP3 inflammasome-related gene expressions (NLRP3, IL-1β, IL-18, and caspase-1). The C3G showed potent inhibitive effects on these NLRP3 inflammasome activation hallmarks induced by HHE. Moreover, we noticed that the C3G's pretreatment leads to a delayed and a decreased JNK activation in HHE-challenged ARPE-19 cells. Finally, using a luciferase reporter gene assay system, we demonstrated that HHE-induced activation protein- (AP-) 1 transcription activity was abolished by C3G pretreatment in a dose-dependent manner. Taken together, these data showed that HHE leads to inflammatory damages to ARPE-19 cells while C3G has great protective effects, highlighting future potential applications of C3G against AMD-associated inflammation.

Resveratrol suppresses hyperglycemia-induced activation of NF-κB and AP-1 via c-Jun and RelA gene regulation

Background: Resveratrol (RSV) provides several important biological functions in wide variety of cells. In this study, we investigated the molecular mechanisms underlying anti-inflammatory effect of RSV on HepG2 cells by assessing the gene expression of RelA and c-Jun- subunits of NF-κB and AP-1 transcription factors.

Methods: HepG2 cells were settled in a serum- free medium with high concentrations of glucose (30 mM) and insulin (1 µM) overnight and were then incubated with RSV (5, 10, and 20 µM) for 24 and 48 hours. Real time quantitative polymerase chain reaction (qRT-PCR) was used to determine RelA and c-Jun expression.

Results: RSV diminished hyperglycemia/hyperinsulinemia stimulated expression of c-Jun dose- dependently after 24 and 48 hours (p<0.05). In addition, RelA gene expression was decreased dose-dependently in all RSV doses after 48-hour incubation (p<0.05). Our results indicated that RSV may reduce NF-κB and AP-1 activity via RelA and c-Jun gene regulation.

Conclusion: The findings of the present study demonstrated that RSV may be considered as a preventative and therapeutic agent for antagonizing inflammation in Hepatocellular carcinoma (HCC).

Mitochondrial dysfunction and oxidative stress in aging and cancer

Aging and cancer are the most important issues to research. The population in the world is growing older, and the incidence of cancer increases with age. There is no doubt about the linkage between aging and cancer. However, the molecular mechanisms underlying this association are still unknown. Several lines of evidence suggest that the oxidative stress as a cause and/or consequence of the mitochondrial dysfunction is one of the main drivers of these processes. Increasing ROS levels and products of the oxidative stress, which occur in aging and age-related disorders, were also found in cancer. This review focuses on the similarities between ageing-associated and cancer-associated oxidative stress and mitochondrial dysfunction as their common phenotype.

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 alleviates diabetes-induced testicular dysfunction by inhibiting oxidative stress and c-Jun N-terminal kinase signaling in rats

Diabetes adversely affects reproductive functions in humans and animals. The present study investigated the effects of Resveratrol on diabetes-induced alterations in oxidative stress, c-Jun N-terminal kinase (JNK) signaling and apoptosis in the testis. Adult male Wistar rats (13-15 weeks; n=6/group) were segregated into 1) normal control, 2) Resveratrol-treated (5mg/kg; ip; given during last 3 weeks), 3) Streptozotocin-induced diabetic and, 4) Resveratrol-treated diabetic groups, and euthanized on day 42 after the confirmation of diabetes. Resveratrol did not normalize blood glucose levels in diabetic rats. Resveratrol supplementation recovered diabetes-induced decreases in reproductive organ weights, sperm count and motility, intra-testicular levels of superoxide dismutase, catalase, and glutathione peroxidase and an increase in 4-hydroxynonenal activities (P<0.05). Resveratrol also recovered diabetes-induced increases in JNK signaling pathway proteins, namely, ASK1 (apoptosis signal-regulating kinase 1), JNKs (46 and 54 kDa isoforms) and p-JNK to normal control levels (P<0.05). Interestingly, the expression of a down-stream target of ASK1, MKK4 (mitogen-activated protein kinase kinase 4) and its phosphorylated form (p-MKK4) did not change in experimental groups. Resveratrol inhibited diabetes-induced increases in AP-1 (activator protein-1) components, c-Jun and ATF2 (activating transcription factor 2), but not their phosphorylated forms, to normal control levels (P<0.05). Further, Resveratrol inhibited diabetes-induced increase in cleaved-caspase-3 to normal control levels. In conclusion, Resveratrol alleviates diabetes-induced apoptosis in testis by modulating oxidative stress, JNK signaling pathway and caspase-3 activities, but not by inhibiting hyperglycemia, in rats. These results suggest that Resveratrol supplementation may be a useful strategy to treat diabetes-induced testicular dysfunction.

Protective effect of resveratrol against caspase 3 activation in primary mouse fibroblasts

Aim

To study the effect of resveratrol on survival and caspase 3 activation in non-transformed cells after serum deprivation.

Methods

Apoptosis was induced by serum deprivation in primary mouse embryonic fibroblasts. Caspase 3 activation and lactate dehydrogenase release were assayed as cell viability measure by using their fluorogenic substrates. The involvement of PI3K, ERK, JNK, p38, and SIRT1 signaling pathways was also examined.

Results

Serum deprivation of primary fibroblasts induced significant activation of caspase 3 within 3 hours and reduced cell viability after 24 hours. Resveratrol dose-dependently prevented caspase activation and improved cell viability with 50% inhibitory concentration (IC₅₀) = 66.3 ± 13.81 µM. It also reduced the already up-regulated caspase 3 activity when it was added to the cell culture medium after 3 hour serum deprivation, suggesting its rescue effect. Among the major signaling pathways, p38 kinase was critical for the protective effect of resveratrol which was abolished completely in the presence of p38 inhibitor.

Conclusion

Resveratrol showed protective effect against cell death in a rather high dose. Involvement of p38 kinase in this effect suggests the role of mild stress in its cytoprotective action. Furthermore due to its rescue effect, resveratrol may be used not only for prevention, but also treatment of age-related degenerative diseases, but in the higher dose than consumed in conventional diet.

Resveratrol prevents cadmium activation of Erk1/2 and JNK pathways from neuronal cell death via protein phosphatases 2A and 5

Cadmium (Cd), a toxic environmental contaminant, induces neurodegenerative disorders. Resveratrol, a natural product, has been found to exert neuroprotective effects. However, little is known regarding the effect of resveratrol on Cd-evoked neurotoxicity. Here, we show that resveratrol effectively reversed Cd-elicited cell viability reduction, morphological change, nuclear fragmentation and condensation, as well as activation of caspase-3 in neuronal cells, implying neuroprotection against Cd-poisoning by resveratrol. Further research revealed that both c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinases 1/2 (Erk1/2) were involved in the inhibitory effect of resveratrol on Cd-induced cell death, as selective inhibitors of Erk1/2 (U0126) and JNK (SP600125), or over-expression of dominant negative mitogen-activated protein kinase kinase 1 (MKK1) or dominant negative c-Jun potentiated resveratrol's prevention of Cd-induced phosphorylation of JNK and Erk1/2, as well as cell death in neuronal cells. Interestingly, resveratrol potently rescued the cells from Cd-induced suppression of protein phosphatases 2A (PP2A) and 5 (PP5) activity. Over-expression of PP2A or PP5 strengthened the inhibitory effects of resveratrol on Cd-induced activation of Erk1/2 and/or JNK, as well as cell death. The results indicate that resveratrol prevents Cd-induced activation of Erk1/2 and JNK pathways and neuronal cell death in part via activating PP2A and PP5. Our findings strongly support the notion that resveratrol may serve as a potential therapeutic agent in the prevention of Cd-induced neurodegenerative diseases.

RNAi-mediated knockdown of the c-jun gene sensitizes radioresistant human nasopharyngeal carcinoma cell line CNE-2R to radiation

This study aimed to investigate the effect of RNA interference (RNAi)-mediated downregulation of the expression of the c-jun gene (a proto-oncogene) on the radiosensitivity of a radioresistant human nasopharyngeal carcinoma cell line (CNE-2R) and to validate its potential as an anticancer target. A lentiviral vector with c-jun small hairpin RNA (shRNA) was constructed and transfected into CNE-2R cells. The gene silencing efficiency of these recombinants was confirmed by RT-PCR and western blotting. Radiosensitivity, cell proliferation, cell cycle profile and apoptosis were assessed using colony formation assay, CCK-8 assay and flow cytometry, respectively. The lentiviral shRNA efficiently knocked down the expression of c-jun at both the mRNA and protein levels (P<0.05). c-jun-downregulated CNE-2R cells exhibited significantly decreased cell proliferation and enhanced radiosensitivity compared to the control group (P<0.05), and the effects were likely due to G2/M phase arrest and enhanced cell apoptosis. These data provide evidence that c-jun may be involved in the radioresistance of nasopharyngeal carcinoma (NPC) and knockdown of the c-jun gene may be a potential strategy to enhance the radiation sensitivity of NPC.

Cell death and diseases related to oxidative stress: 4-hydroxynonenal (HNE) in the balance

During the last three decades, 4-hydroxy-2-nonenal (HNE), a major α,β-unsaturated aldehyde product of n-6 fatty acid oxidation, has been shown to be involved in a great number of pathologies such as metabolic diseases, neurodegenerative diseases and cancers. These multiple pathologies can be explained by the fact that HNE is a potent modulator of numerous cell processes such as oxidative stress signaling, cell proliferation, transformation or cell death. The main objective of this review is to focus on the different aspects of HNE-induced cell death, with a particular emphasis on apoptosis. HNE is a special apoptotic inducer because of its abilities to form protein adducts and to propagate oxidative stress. It can stimulate intrinsic and extrinsic apoptotic pathways and interact with typical actors such as tumor protein 53, JNK, Fas or mitochondrial regulators. At the same time, due to its oxidant status, it can also induce some cellular defense mechanisms against oxidative stress, thus being involved in its own detoxification. These processes in turn limit the apoptotic potential of HNE. These dualities can imbalance cell fate, either toward cell death or toward survival, depending on the cell type, the metabolic state and the ability to detoxify.

Apoptosis signalling by 4-hydroxynonenal: a role for JNK–c-Jun/AP-1 pathway

4-Hydroxynonenal (HNE) is one of the most abundant aldehyde components of ox-LDL and it exerts various effects on intracellular and extracellular signaling cascades. In this mini-review, a brief synopsis of HNE-modulated signaling pathways will be presented mainly focused on cell death, including recent studies from our laboratory. The results of a number of studies demonstrate the ability of HNE to induce apoptosis and ROS formation in a dose-dependent manner. Several signaling pathways have been shown to be modulated by HNE, including MAP kinases, PKC isoforms, cell-cycle regulators, receptor tyrosine kinases and caspases. In order to get insight into the mechanisms of apoptotic response by HNE, MAP kinase and caspase activation pathways have been studied in 3T3 fibroblasts; HNE induced early activation of JNK and p38 proteins but down-regulated the basal activity of ERK-1/2. We have shown that HNE-induced release of cytochrome c from mitochondria, caspase-9 and caspase-3 activation. Activation of AP-1 along with increased c-Jun and phospho-c-Jun levels could be inhibited by pretreatment of cells with certain molecules such as resveratrol. Additionally, overexpression of dominant negative c-Jun and JNK1 in 3T3 fibroblasts prevented HNE-induced apoptosis, which indicated a role for JNK-c-Jun/AP-1 pathway. JNK-dependent induction of c-Jun/AP-1 activation data in the literature indicates a critical potential role for JNK in the cellular response against toxic products of lipid peroxidation.

Inactivation of Bcl-2 through IκB kinase (IKK)-dependent phosphorylation mediates apoptosis upon exposure to 4-hydroxynonenal (HNE)

Apoptosis of macrophage foam cells loaded with modified/oxidized lipids is implicated in destabilization of advanced atherosclerotic plaques in humans. Concentration of HNE, main aldehydic product of plasma LDL peroxidation, elevates in atherosclerotic lesions as well as in cultured cells under oxidative stress. Although this reactive aldehyde has been shown to promote apoptosis with the involvement of p38 MAPK and JNK in various mammalian cell lines, roles of B-cell lymphoma 2 (Bcl-2) family proteins remain to be deciphered. We demonstrated that HNE-induced apoptosis was accompanied by concurrent downregulations of antiapoptotic Bcl-x(L) and Mcl-1 as well as upregulation of proapoptotic Bak. Furthermore, phoshorylation of Bcl-2 at Thr56, Ser70, and probably more phosphorylation sites located on N-terminal loop domain associated with HNE-induced apoptosis in both U937 and HeLa cells while ectopic expression of a phospho-defective Bcl-2 mutant significantly attenuated apoptosis. In parallel to this, HNE treatment caused release of proapoptotic Bax from Bcl-2. Pharmacological inhbition of IKK inhibited HNE-induced Bcl-2 phosphorylation. Similarly, silencing IKKα and -β both ended up with abrogation of Bcl-2 phosphorylation along with attenuation of apoptosis. Moreover, both IKKα and -β coimmunoprecipitated with Bcl-2 and in vitro kinase assay proved the ability of IKK to phosphorylate Bcl-2. In view of these findings and considering HNE inhibits DNA-binding activity of nuclear factor-κB (NF-κB) through prevention of IκB phosphorylation/ubiquitination/proteolysis, IKK appears to directly interfere with Bcl-2 activity through phosphorylation in HNE-mediated apoptosis independent of NF-κB signaling.

Resveratrol preconditioning modulates inflammatory response in the rat hippocampus following global cerebral ischemia

Considerable evidence has been accumulated to suggests that blocking the inflammatory reaction promotes neuroprotection and shows therapeutic potential for clinical treatment of ischemic brain injury. Consequently, anti-inflammatory therapies are being explored for prevention and treatment of these diseases. Induction of brain tolerance against ischemia by pretreatment with resveratrol has been found to influence expression of different molecules. It remains unclear, however, whether and how resveratrol preconditioning changes expression of inflammatory mediators after subsequent global cerebral ischemia/reperfusion (I/R). Therefore, we investigated the effect of resveratrol pretreatment on NF-κB inflammatory cascade, COX-2, iNOS and JNK levels in experimental I/R. Adult male rats were subjected to 10 min of four-vessel occlusion and sacrificed at selected post-ischemic time points. Resveratrol (30 mg/kg) pretreatment was injected intraperitoneally 7 days prior to I/R induction. We found that resveratrol treatment before insult remarkably reduced astroglial and microglial activation at 7 days after I/R. It greatly attenuated I/R-induced NF-κB and JNK activation with decreased COX-2 and iNOS production. In conclusion, the neuroprotection of resveratrol preconditioning may be due in part to the suppression of the inflammatory response via regulation of NF-κB, COX-2 and iNOS induced by I/R. JNK was also suggested to play a protective role through in neuroprotection of resveratrol, which may also be contributing to reduction in neuroinflammation. The study adds to a growing literature that resveratrol can have important anti-inflammatory actions in the brain.

Resveratrol prevents impairment in activation of retinoic acid receptors and MAP kinases in the embryos of a rodent model of diabetic embryopathy

Diabetes induces impairments in gene expression during embryonic development that leads to premature and improper tissue specialization. Retinoic acid receptors (RARs and retinoid X receptor [RXRs]) and mitogen-activated protein kinases (MAPKs) play crucial roles during embryonic development, and their suppression or activation has been shown as a determinant of the fate of embryonic organogenesis. We studied the activation of RARs and MAPKs in embryonic day 12 (E12) in embryos of rats under normal, diabetic, and diabetic treated with resveratrol ([RSV]; 100 mg/kg body weight) conditions. We found downregulation of RARs and RXRs expressions as well as their DNA-binding activities in the embryos exhibiting developmental delays due to diabetes. Furthermore, the phosphorylation of extracellular signal-regulated kinase (ERK) 1/2 was decreased and phosphorylation of c-Jun N-terminal kinase (JNK) 1/2 and p38 was increased. Interestingly, embryos of diabetic rats treated with RSV showed normalized patterns of RARs, RXRs, neuronal markers, and ERK, JNK and p38 phosphorylation.

Resveratrol inhibition of inducible nitric oxide synthase in skeletal muscle involves AMPK but not SIRT1

The plant-derived polyphenol resveratrol (RSV) modulates life span and metabolism, and it is thought that these effects are largely mediated by activating the deacetylase enzyme SIRT1. However, RSV also activates the cell energy sensor AMP-activated protein kinase (AMPK). We have previously reported that AMPK activators inhibit inducible nitric oxide synthase (iNOS), a key proinflammatory mediator of insulin resistance in endotoxemia and obesity. The aim of this study was to evaluate whether RSV inhibits iNOS induction in insulin target tissues and to determine the role of SIRT1 and AMPK activation in this effect. We found that RSV (40 mg/kg ip) treatment decreased iNOS induction and NO production in skeletal muscle and white adipose tissue, but not in liver, of endotoxin (LPS)-challenged mice. This effect of the polyphenol was recapitulated in vitro, where RSV (10-80 μM) robustly inhibited iNOS protein induction and NO production in cytokine/LPS-treated L6 myocytes and 3T3-L1 adipocytes. However, no effect of RSV was observed on iNOS induction in FAO hepatocytes. Further studies using inhibitors of SIRT1 revealed that the deacetylase enzyme is not involved in RSV action on iNOS. In marked contrast, RSV activates AMPK in L6 myocytes, and blunting its activation using Compound C or RNA interference partly blocked the inhibitory effect of RSV on NO production. These results show that RSV specifically inhibits iNOS induction in muscle through a mechanism involving AMPK but not SIRT1 activation. This anti-inflammatory action of RSV likely contributes to the therapeutic effect of this plant polyphenol.

Resveratrol inhibits Cdk5 activity through regulation of p35 expression

Background

We have previously reported that cyclin-dependent kinase 5 (Cdk5) participates in the regulation of nociceptive signaling. Through activation of the ERK1/2 pathway, Tumor Necrosis Factor-α (TNF-α) induces expression of Egr-1. This results in the sustained and robust expression of p35, a coactivator of Cdk5, in PC12 cells, thereby increasing Cdk5 kinase activity. The aim of our present study was to test whether resveratrol, a polyphenolic compound with known analgesic activity, can regulate Cdk5/p35 activity.

Results

Here we used a cell-based assay in which a p35 promoter-luciferase construct was stably transfected in PC12 cells. Our studies demonstrate that resveratrol inhibits p35 promoter activity and also blocks the TNF-α mediated increase in Cdk5 activity in PC12 cells. Resveratrol also inhibits p35 expression and blocks the TNF-α mediated increase in Cdk5 activity in DRG neurons. In the presence of resveratrol, the MEK inhibitor decreased p35 promoter activity, whereas the inhibitors of p38 MAPK, JNK and NF-κB increased p35 promoter activity, indicating that these pathways regulate p35 expression differently. The TNF-α-mediated increase in Egr-1 expression was decreased by resveratrol treatment with a concomitant reduction in p35 expression and protein levels, resulting in reduced Cdk5 kinase activity.

Conclusions

We demonstrate here that resveratrol regulates p35 promoter activity in PC12 cells and DRG neurons. Most importantly, resveratrol blocks the TNF-α-mediated increase in p35 promoter activity, thereby reducing p35 expression and subsequent Cdk5 kinase activity. This new molecular mechanism adds to the known analgesic effects of resveratrol and confirms the need for identifying new analgesics based on their ability to inhibit Cdk5 activity for effective treatment of pain.

Multifaceted approach to resveratrol bioactivity: Focus on antioxidant action, cell signaling and safety

Resveratrol (RVT) is a naturally occurring trihydroxy stilbene that displays a wide spectrum of physiological activity. Its ability to behave therapeutically as a component of red wine has attracted wide attention. The phenol acts as a protective agent involving various body constituents. Most attention has been given to beneficial effects in insults involving cancer, aging, cardiovascular system, inflammation and the central nervous system. One of the principal modes of action appears to be as antioxidant. Other mechanistic pathways entail cell signaling, apoptosis and gene expression. There is an intriguing dichotomy in relation to pro-oxidant property. Also discussed are metabolism, receptor binding, rationale for safety and suggestions for future work. This is the first comprehensive review of RVT based on a broad, unifying mechanism.

Functional aspects of redox control during neuroinflammation

Neuroinflammation is a CNS reaction to injury in which some severe pathologies, regardless of their origin, converge. The phenomenon emphasizes crosstalk between neurons and glia and reveals a complex interaction with oxidizing agents through redox sensors localized in enzymes, receptors, and transcription factors. When oxidizing pressures cause reversible molecular changes, such as minimal or transitory proinflammatory cytokine overproduction, redox couples provide a means of translating the presence of reactive oxygen or nitrogen species into useful signals in the cell. Additionally, thiol-based redox sensors convey information about localized changes in redox potential induced by physiologic or pathologic situations. They are susceptible to oxidative changes and become key events during neuroinflammation, altering the course of a signaling response or the behavior of specific transcription factors. When oxidative stress augments the pressure on the intracellular environment, the effective reduction potential of redox pairs diminishes, and cell signaling shifts toward proinflammatory and proapoptotic signals, creating a vicious cycle between oxidative stress and neuroinflammation. In addition, electrophilic compounds derived from the oxidative cascade react with key protein thiols and interfere with redox signaling. This article reviews the relevant functional aspects of redox control during the neuroinflammatory process.

Resveratrol attenuates radiation damage in Caenorhabditis elegans by preventing oxidative stress

Resveratrol, a member of a class of polyphenolic compounds known as flavonols, has been extensively studied for its anticancer, antiviral, anti-inflammatory, and neuroprotective roles. Caenorhabidits elegans is a well-established animal for investigating responses to radiation. We found that resveratrol may provide protection against hazardous radiation. Pre-treatment with resveratrol extended both the maximum and mean life span of irradiated C. elegans. Resveratrol acted as a strong radical scavenger and regulated superoxide dismutase (SOD) expression. In addition, resveratrol was shown to be capable of alleviating gamma-ray radiation exposure-induced reduction in mitochondrial SOD expression. Ultimately, a correlation may exist between dietary intake of trace amounts of resveratrol and anti-aging effects. A specific response mechanism may be activated after the administration of resveratrol in irradiated animals. Our results suggest the protective effect of resveratrol is due to its strong ability to protect from oxidative stress and protective effects in mitochondria. Therefore, resveratrol is potentially an effective protecting agent against irradiative damage.

Lifestyle-induced metabolic inflexibility and accelerated ageing syndrome: insulin resistance, friend or foe?

The metabolic syndrome may have its origins in thriftiness, insulin resistance and one of the most ancient of all signalling systems, redox. Thriftiness results from an evolutionarily-driven propensity to minimise energy expenditure. This has to be balanced with the need to resist the oxidative stress from cellular signalling and pathogen resistance, giving rise to something we call 'redox-thriftiness'. This is based on the notion that mitochondria may be able to both amplify membrane-derived redox growth signals as well as negatively regulate them, resulting in an increased ATP/ROS ratio. We suggest that 'redox-thriftiness' leads to insulin resistance, which has the effect of both protecting the individual cell from excessive growth/inflammatory stress, while ensuring energy is channelled to the brain, the immune system, and for storage. We also suggest that fine tuning of redox-thriftiness is achieved by hormetic (mild stress) signals that stimulate mitochondrial biogenesis and resistance to oxidative stress, which improves metabolic flexibility. However, in a non-hormetic environment with excessive calories, the protective nature of this system may lead to escalating insulin resistance and rising oxidative stress due to metabolic inflexibility and mitochondrial overload. Thus, the mitochondrially-associated resistance to oxidative stress (and metabolic flexibility) may determine insulin resistance. Genetically and environmentally determined mitochondrial function may define a 'tipping point' where protective insulin resistance tips over to inflammatory insulin resistance. Many hormetic factors may induce mild mitochondrial stress and biogenesis, including exercise, fasting, temperature extremes, unsaturated fats, polyphenols, alcohol, and even metformin and statins. Without hormesis, a proposed redox-thriftiness tipping point might lead to a feed forward insulin resistance cycle in the presence of excess calories. We therefore suggest that as oxidative stress determines functional longevity, a rather more descriptive term for the metabolic syndrome is the 'lifestyle-induced metabolic inflexibility and accelerated ageing syndrome'. Ultimately, thriftiness is good for us as long as we have hormetic stimuli; unfortunately, mankind is attempting to remove all hormetic (stressful) stimuli from his environment.

Ferulaldehyde, a water-soluble degradation product of polyphenols, inhibits the lipopolysaccharide-induced inflammatory response in mice

Antiinflammatory properties of polyphenols in natural products, traditional medicines, and healthy foods were recently attributed to highly soluble metabolites produced by the microflora of the intestines rather than the polyphenols themselves. To provide experimental basis for this hypothesis, we measured antiinflammatory properties of ferulaldehyde (FA), a natural intermediate of polyphenol metabolism of intestinal microflora, in a murine lipopolysaccharide (LPS)-induced septic shock model. We found that intraperitoneally administered FA (6 mg/kg) prolonged the lifespan of LPS-treated (40 mg/kg) mice, decreased the inflammatory response detected by T(2)-weighted in vivo MRI, decreased early proinflammatory cytokines such as tumor necrosis factor-alpha and interleukin (IL)-1beta, and increased the antiinflammatory IL-10 in the sera of the mice. Additionally, FA inhibited LPS-induced activation of nuclear factor kappaB transcription factor in the liver of the mice. According to our data, these effects were probably due to attenuating LPS-induced activation of c-Jun N-terminal kinase and Akt. Furthermore, FA decreased free radical and nitrite production in LPS plus interferon-gamma-treated primary mouse hepatocytes, whose effects are expected to contribute to its antiinflammatory property. These data provide direct in vivo evidence, that a water-soluble degradation product of polyphenols could be responsible for, or at least could significantly contribute to, the beneficial antiinflammatory effects of polyphenol-containing healthy foods, natural products, and traditional medicines.

Substituted trans-stilbenes can inhibit or enhance the TPA-induced up-regulation of activator protein-1

Background

The activator protein-1 (AP-1) family of transcription factors contributes to regulation of numerous genes involved in proliferation, apoptosis, and tumorigenesis. A wide array of stimuli can activate AP-1, including pro-inflammatory cytokines, growth factors, tumor promoters and stress. Numerous plant polyphenols have been shown to inhibit the activation of AP-1, which often is ascribed to the anti-oxidant properties of these natural products.

Methods

In the present study, a library of substituted trans-stilbenes, including polyphenols, was screened for activity against the TPA-induced activation of AP-1 using the Panomics AP-1 Reporter 293 Stable Cell Line, which is designed for screening potential inhibitors or activators.

Results

Several trans-stilbenes were identified that inhibit TPA-induced activation of AP-1, with IC₅₀ values as low as 0.5 μM. Moreover, some other trans-stilbenes were able to enhance the effects of TPA 2 to 3-fold. Many of the trans-stilbenes identified as inhibitors or enhancers are devoid of anti-oxidant properties.

Conclusion

The ability of trans-stilbenes to inhibit or enhance the effects of TPA does not depend upon their anti-oxidant properties.

Decreased iPLA2gamma expression induces lipid peroxidation and cell death and sensitizes cells to oxidant-induced apoptosis

Our previous studies showed that renal proximal tubular cells (RPTC) express Ca(2+)-independent phospholipase A(2)gamma (iPLA(2)gamma) in endoplasmic reticulum (ER) and mitochondria and that iPLA(2)gamma prevents and/or repairs lipid peroxidation induced by oxidative stress. Our present studies determined the importance of iPLA(2)gamma in mitochondrial and cell function using an iPLA(2)gamma-specific small hairpin ribonucleic acid (shRNA) adenovirus. iPLA(2)gamma expression and activity were decreased in the ER by 24 h and in the mitochondria by 48 h compared with scrambled shRNA adenovirus-treated cells. Lipid peroxidation was elevated by 2-fold at 24 h and remained elevated through 72 h in cells with decreased iPLA(2)gamma. Using electrospray ionization-mass spectrometry, primarily phosphatidylcholines and phosphatidylethanolamines were increased in iPLA(2)gamma-shRNA-treated cells. At 48 h after exposure to the iPLA(2)gamma shRNA, uncoupled oxygen consumption was inhibited by 25% and apoptosis was observed at 72 and 96 h. RPTC with decreased iPLA(2)gamma expression underwent apoptosis when exposed to a nonlethal concentration of the oxidant tert-butyl hydroperoxide (TBHP). Exposure of control cells to a nonlethal concentration of TBHP induced iPLA(2)gamma expression in RPTC. These results suggest that iPLA(2)gamma is required for the prevention and repair of basal lipid peroxidation and the maintenance of mitochondrial function and viability, providing further evidence for a cytoprotective role for iPLA(2)gamma from oxidative stress.

Phytochemical regulation of UDP-glucuronosyltransferases: implications for cancer prevention

Uridine 5'-diphospho-glucuronosyltransferases (UGTs) are Phase II biotransformation enzymes that metabolize endogenous and exogenous compounds, some of which have been associated with cancer risk. Many phytochemicals have been shown to induce UGTs in humans, rodents, and cell culture systems. Because UGTs maintain hormone balance and facilitate excretion of potentially carcinogenic compounds, regulation of their expression and activity may affect cancer risk. Phytochemicals regulate transcription factors such as the nuclear factor-erythroid 2-related factor 2 (Nrf2), aryl hydrocarbon, and pregnane X receptors as well as proteins in several signal transduction cascades that converge on Nrf2 to stimulate UGT expression. This induction can be modified by several factors, including phytochemical dose and bioavailability and interindividual variation in enzyme expression. In this review, we summarize the knowledge of dietary modulation of UGTs, particularly by phytochemicals, and discuss the potential mechanisms by which phytochemicals regulate UGT transcription.

Polypeptide from Chlamys farreri attenuates murine thymocytes damage induced by ultraviolet B

AIM

Polypeptide from Chlamys farreri (PCF, molecular mass is 879) is a new marine polypeptide compound isolated from Chlamys farreri. This study investigates the possible protective roles and the mechanism of PCF against ultraviolet B (UVB)-induced apoptosis in murine thymocytes.

METHODS

The rate of apoptosis and caspase-3 activation was measured by flow cytometry. The expression of stress-response genes c-fos and c-jun was observed by RT-PCR. Western blot analysis was performed to determine the release of cytochrome c.

RESULTS

It was found that UVB induced murine thymocyte death. The cells treated with UVB showed an increase in cytochrome c release, caspase-3 activity, as well as in the expression of c-fos and c-jun. In addition, all were involved in UVB-induced cell apoptosis.

CONCLUSION

Our present observations pointed to the ability of PCF to avert UVB-induced apoptosis in thymocytes by modulating c-fos and c-jun expression, cytochrome c release, and the consequent activation of caspase-3, which were essential components of the UV-induced cell apoptotic pathway. The results suggested that PCF is a promising protective substance against UV radiation.

Pharmacological concentration of resveratrol suppresses aromatase in JEG-3 cells

Estrogen is crucial in preparing of pregnancy, and its role in the maintenance of pregnancy has yet to be elucidated. During the course of pregnancy, the placenta is responsible for the provision of estrogen. The hormone biosynthesis is catalyzed by cytochrome P450 (CYP) 19 or aromatase. In the present study, we screened several common dietary components and identified the grape polyphenol resveratrol to be a potential inhibitor in the hormone synthesis. In a recombinant protein system resveratrol inhibited the aromatase activity with an IC(50) value of approximately 40 microM. Subsequent analysis was performed in the human placental JEG-3 cells, and 25 microM resveratrol significantly reduced the mRNA abundance in these cells. Since the transcriptional control of CYP19 gene is tissue-specific and the proximal promoter region of exon Ia has previously been shown to be crucial in CYP19 expression in placental cells, we also evaluated the promoter activity of this gene. Reporter gene assays revealed that resveratrol repressed the transcriptional control of promoter Ia. The present study illustrated the possibility that dietary supplementation of resveratrol interfered with the normal functioning of placental cells.

Nrf2 is involved in the effect of tanshinone IIA on intracellular redox status in human aortic smooth muscle cells

Tanshinone IIA is the major antioxidant component in the traditional Chinese medicine Salvia miltiorrhiza. Transcription factor nuclear-factor-E2-related factor (Nrf2) regulates a battery of antioxidant response element (ARE)-regulated genes. The aim of this study was to determine the effect of tanshinone IIA on Nrf2 activation and intracellular redox status in human aortic smooth muscle cells. Tanshinone IIA potentiated tumor necrosis factor alpha (TNF-alpha)-mediated nuclear accumulation of Nrf2 and expression of ARE-related genes, while it reversed TNF-alpha-induced down-regulation of intracellular glutathione (GSH), NADPH and glucose 6-phosphate dehydrogenase (G6PDH) levels. Specific silence of Nrf2 by siRNA down-regulated tanshinone IIA-induced Nrf2 activation and increased of intracellular GSH, NADPH and G6PDH levels. Tanshinone IIA-induced Nrf2 activation was association with activation of ERK and PKB, which was prevented by treatment with PD098059 or wortmannin. Tanshinone IIA attenuated TNF-alpha, angiotensin II, H(2)O(2)-mediated reactive oxygen species (ROS) production. These results demonstrated that tanshinone IIA-induced Nrf2 activation is the major regulatory pathway of cytoprotective gene expression against oxidative stress via ERK and PKB signaling pathways.

Role of peroxisome proliferator-activated receptor-γ in resveatrol-induced proliferation inhibition of gastric cancer cell line SGC-7901

AIM: To investigate the role of peroxisome proliferator-activated receptor-γ (PPAR-γ) in the inhibitory effects of resveratrol (Res) on gastric cancer cell SGC-7901 proliferation in vitro.

METHODS: After human gastric cancer cell SGC-7901 was cultured in vitro, MTT assay was used to detect the inhibitory effect of Res and GW9662 (specific blocker of PPAR-γ) on cell proliferation. Flow cytometry was used to detect cell cycle, and PPAR-γ, Cyclin D1 mRNA was measured quantitatively by reverse transcription-polymerase chain reaction (RT-PCR). The expression of PPAR-γ protein was measured quantitatively by Western blot, and the expression of Cyclin D1 protein in gastric cancer cells was detected by immunohistochemistry.

RESULTS: Res inhibited the proliferation of SGC-7901 cells in a dose- and time-dependent manner (P < 0.05), and flow cytometry analysis revealed that the cell cycle was blocked at G₁-phase. RT-PCR and Western blot showed that both PPAR-γ mRNA and protein were expressed in SGC-7901 cells, and Res enhanced PPAR-γ mRNA expression. After SGC-7901 cells were treated by Res with the concentration of 25, 50, 75 and 100 μmol/L, the relative percentages of PPAR-γ mRNA expression were 122.2%, 195.1%, 232.9% and 277.1% of those in the controls (P < 0.05), but the expression of PPAR-γ protein didn't changed. The high levels of Cyclin D1 mRNA and protein expression were detected in SGC-7901 cells, while Res significantly decreased the expression of Cyclin D1. After SGC-7901 cells were treated by Res with the concentration of 25, 50, 75 and 100 mmol/L, the inhibitory rates of Cyclin D1 mRNA were 11.3%, 24.3%, 35.4% and 59.5%, respectively, while GW9662 markedly decreased the above effects of Res.

CONCLUSION: Res can significantly inhibit Cyclin D1 expression partly by activating PPAR-γ in gastric cancer cells SGC-7901, which results in the blockage of cell cycle at G₁ phase and inhibition of cell proliferation.

Differential proteomic profiling to study the mechanism of cardiac pharmacological preconditioning by resveratrol

Recent studies demonstrated that resveratrol, a grape-derived polyphenolic phytoalexin, provides pharmacological preconditioning of the heart through a NO-dependent mechanism. To further explore the molecular mechanisms involved in resveratrol-mediated cardioprotection, we monitored the effects of resveratrol treatment after ischemia-reperfusion on the protein profile by implementation of proteomic analysis. Two groups of rats were studied; one group of animals was fed resveratrol for 7 days, while the other group was given vehicle only. The rats were sacrificed for the isolated working heart preparation and for isolation of cytoplasmic fraction from left ventricle homogenates to carry out the proteomic as well as immunoblot at baseline and at the end of 30 min ischemia/2-h perfusion. The results demonstrate significant cardioprotection with resveratrol evidenced by improved ventricular recovery and reduced infarct size and cardiomyocyte apoptosis. The left ventricular cytoplasmic fractions were separated by two-dimensional electrophoresis (2-DE). Differentially regulated proteins were detected with quantitative computer analysis of the Coomassie blue stained 2-DE images and identified by MALDI-TOF (MS) and nanoLC-ESI-Q-TOF mass spectrometry (MS/MS). Five redox-regulated and preconditioning- related proteins were identified that were all upregulated by resveratrol: MAPKK, two different alphaB-crystallin species, HSP 27 and PE binding protein. Another HSP27 species and aldose reductase were downregulated and peroxiredoxin- 2 remained constant. The results of the immunoblot analysis of phosphorylated MAPKK, -HSP27 and -alphaB-crystallin and PE binding protein were consistent with the proteomic findings, but not with peroxiredoxin-2. The proteomic analysis showed also downregulation of some proteins in the mitochondrial respiratory chain and matrix and the myofilament regulating protein MLC kinase-2. The results of the present study demonstrate that proteomic profiling enables the identification of resveratrol induced preconditioning-associated proteins which reflects not only changes in their expression level but also isoforms, post-translational modifications and regulating binding or activating partner proteins.