Nrf2 regulates downstream genes by targeting miR-29b in severe asthma and the role of grape seed proanthocyanidin extract in a murine model of steroid-insensitive asthma

CONTEXT

Grape seed proanthocyanidin extract (GSPE) is effective in treating severe asthma (SA).

OBJECTIVE

To examine the relationship between Nrf2-miR-29b axis and SA, and to detect whether preventive use of GSPE relieves SA via it.

MATERIALS AND METHODS

We recruited 10 healthy controls, 10 patients with non-severe asthma (nSA), and 9 patients with SA from February 2017 to December 2017. Peripheral blood mononuclear cells from these volunteers were extracted. A murine model of steroid-insensitive asthma was established in six-week-old female BALB/c mice that were sensitised and challenged with OVA, Al(OH)₃ and LPS for 31 days. Mice in the treated groups were injected with DXM (5 mg/kg/d), with or without GSPE (100 mg/kg/d). Control group received PBS. We performed quantitative real-time PCR, western blot and luciferase reporter assay in animal and cell models.

RESULTS

SA group demonstrated significantly lower concentrations of Nrf2 protein, Nrf2 mRNA, and miR-29b than nSA group and control group. Conversely, higher levels of platelet derived growth factor C (PDGFC), phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1), and collagen type III alpha 1 (COL3A1) were measured in SA than in the other two groups. PDGFC, PIK3R1, and COL3A1 were the target genes of miR-29b. GSPE + DXM significantly elevated the expression of Nrf2 (+188%), Nrf2 mRNA (+506%), and miR-29b (+201%), and significantly reduced the expression of PDGFC (-72%), PIK3R1 (-40%), and COL3A1 (-65%) compared with OVA + LPS.

CONCLUSIONS

Nrf2-miR-29b axis is involved in the pathogenesis of SA. GSPE, as an adjuvant drug, maybe a potential therapeutic agent for SA.

Emu oil and grape seed extract reduce tumour burden and disease parameters in murine colitis-associated colorectal cancer

Ulcerative colitis is an incurable condition whereby patients are at an increased risk of developing colorectal cancer (CRC). We aimed to investigate the combination of Emu oil (EO) and grape seed extract (GSE) in an azoxymethane (AOM)/dextran sulphate sodium (DSS) model of colitis-associated CRC (CA-CRC). C57BL/6 mice (n = 10/group) were injected i.p. with saline or AOM (7.4 mg/kg) and underwent three DSS/water cycles. Mice were orally-gavaged thrice weekly with water (80 μl), EO (80 μl), GSE (80 μl; 400 mg/kg) or combined EO/GSE (160 μl). Mice were euthanized on day 63. AOM/DSS induced significant bodyweight loss (max -21%) and increased disease activity index (DAI) (max +83%) throughout the trial (P < 0.05). EO (max -53%), GSE (max -51%) and EO/GSE (max -71%) reduced DAI scores in AOM/DSS mice in all DSS cycles (P < 0.05). EO/GSE-treatment in AOM/DSS mice resulted in further DAI reduction compared with EO (max -62%) and GSE (max -71%) alone (P < 0.05). AOM/DSS mice presented with severe colonoscopically-assessed colitis at all time-points, which was reduced by EO, GSE and EO/GSE (P < 0.05). EO, GSE and EO/GSE reduced the number of colonic tumours compared with AOM/DSS controls (P < 0.05). Myeloperoxidase (acute inflammation) and fluorescein isothiocyanate-dextran levels (intestinal permeability) were increased in AOM/DSS controls (P < 0.05). EO (-58%) and EO/GSE (-77%) reduced fluorescein isothiocyanate-dextran compared with AOM/DSS controls (P < 0.05), with no effect on myeloperoxidase. Histologically-assessed severity scores were increased in the distal colon of AOM/DSS mice compared with saline (P < 0.05), with no effect observed following treatment. The combination of EO and GSE improved clinical indicators and reduced colonic tumours in AOM/DSS treated mice, suggesting potential in CA-CRC management.

Glucagon Shows Higher Sensitivity than Insulin to Grapeseed Proanthocyanidin Extract (GSPE) Treatment in Cafeteria-Fed Rats

The endocrine pancreas plays a key role in metabolism. Procyanidins (GSPE) targets β-cells and glucagon-like peptide-1 (GLP-1)-producing cells; however, there is no information on the effects of GSPE on glucagon. We performed GSPE preventive treatments administered to Wistar rats before or at the same time as they were fed a cafeteria diet during 12 or 17 weeks. We then measured the pancreatic function and GLP-1 production. We found that glucagonemia remains modified by GSPE pre-treatment several weeks after the treatment has finished. The animals showed a higher GLP-1 response to glucose stimulation, together with a trend towards a higher GLP-1 receptor expression in the pancreas. When the GSPE treatment was administered every second week, the endocrine pancreas behaved differently. We show here that glucagon is a more sensitive parameter than insulin to GSPE treatments, with a secretion that is highly linked to GLP-1 ileal functionality and dependent on the type of treatment.

Entelon (vitis vinifera seed extract) reduces degenerative changes in bovine pericardium valve leaflet in a dog intravascular implant model

Background and aims

Inflammation and calcification are major factors responsible for degeneration of bioprosthetic valve and other substitute heart valve implantations. The objective of this study was to evaluate the anti-inflammatory and anti-calcification effects of Entelon150^® (consisting of grape-seed extract) in a beagle dog model of intravascular bovine pericardium implantation.

Methods

In total, 8 healthy male beagle dogs were implanted with a bovine pericardium bilaterally in the external jugular veins and divided into two groups. Animals in the Entelon150^® group (n = 4) were treated with 150 mg of Entelon150^® twice daily for six weeks after surgery. The negative control (NC) group (n = 4) was treated with 5 ml of saline using the same method. After six weeks, we measured the calcium content, performed histological examination, and performed molecular analysis.

Results

The calcium content of implanted tissue in the Entelon150^® group (0.56±0.14 mg/g) was significantly lower than that in the NC group (1.48±0.57 mg/g) (p < 0.05). Histopathological examination showed that infiltration of chronic inflammatory cells, such as fibroblasts and macrophages, occurred around the graft in all groups; however, the inflammation level of the implanted tissue in the Entelon150^® group was s lower than that in the NC group. Both immunohistochemical and western blot analyses revealed that bone morphogenetic protein 2 expression was significantly attenuated in the Entelon150^® group.

Conclusions

Our results indicate that Entelon150^® significantly attenuates post-implantation inflammation and degenerative calcification of the bovine pericardium in dogs. Therefore, Entelon150^® may increase the longevity of the bovine pericardium after intravascular implantation.

Pathophysiological Basis for Nutraceutical Supplementation in Heart Failure: A Comprehensive Review

There is evidence demonstrating that heart failure (HF) occurs in 1–2% of the global population and is often accompanied by comorbidities which contribute to increasing the prevalence of the disease, the rate of hospitalization and the mortality. Although recent advances in both pharmacological and non-pharmacological approaches have led to a significant improvement in clinical outcomes in patients affected by HF, residual unmet needs remain, mostly related to the occurrence of poorly defined strategies in the early stages of myocardial dysfunction. Nutritional support in patients developing HF and nutraceutical supplementation have recently been shown to possibly contribute to protection of the failing myocardium, although their place in the treatment of HF requires further assessment, in order to find better therapeutic solutions. In this context, the Optimal Nutraceutical Supplementation in Heart Failure (ONUS-HF) working group aimed to assess the optimal nutraceutical approach to HF in the early phases of the disease, in order to counteract selected pathways that are imbalanced in the failing myocardium. In particular, we reviewed several of the most relevant pathophysiological and molecular changes occurring during the early stages of myocardial dysfunction. These include mitochondrial and sarcoplasmic reticulum stress, insufficient nitric oxide (NO) release, impaired cardiac stem cell mobilization and an imbalanced regulation of metalloproteinases. Moreover, we reviewed the potential of the nutraceutical supplementation of several natural products, such as coenzyme Q10 (CoQ10), a grape seed extract, Olea Europea L.-related antioxidants, a sodium–glucose cotransporter (SGLT2) inhibitor-rich apple extract and a bergamot polyphenolic fraction, in addition to their support in cardiomyocyte protection, in HF. Such an approach should contribute to optimising the use of nutraceuticals in HF, and the effect needs to be confirmed by means of more targeted clinical trials exploring the efficacy and safety of these compounds.

A Ten-Day Grape Seed Procyanidin Treatment Prevents Certain Ageing Processes in Female Rats over the Long Term

Adaptive homeostasis declines with age and this leads to, among other things, the appearance of chronic age-related pathologies such as cancer, neurodegeneration, osteoporosis, sarcopenia, cardiovascular disease and diabetes. Grape seed-derived procyanidins (GSPE) have been shown to be effective against several of these pathologies, mainly in young animal models. Here we test their effectiveness in aged animals: 21-month-old female rats were treated with 500 mg GSPE/kg of body weight for ten days. Afterwards they were kept on a chow diet for eleven weeks. Food intake, body weight, metabolic plasma parameters and tumor incidence were measured. The GSPE administered to aged rats had an effect on food intake during the treatment and after eleven weeks continued to have an effect on visceral adiposity. It prevented pancreas dysfunction induced by ageing and maintained a higher glucagon/insulin ratio together with a lower decrease in ketonemia. It was very effective in preventing age-related tumor development. All in all, this study supports the positive effect of GSPE on preventing some age-related pathologies.

The effect of grape seed and green tea extracts on the pharmacokinetics of imatinib and its main metabolite, N-desmethyl imatinib, in rats

BACKGROUND

Imatinib is mainly metabolized by CYP3A4 and to a lesser extent by other isoenzymes, with N-desmethyl imatinib being its major equipotent metabolite. Being a CYP3A4 substrate, imatinib co-administration with CYP3A4 modulators would change its pharmacokinetic profile. The cancer chemoprevention potential and anticancer efficacy of many herbal products such as grape seed (GS) and green tea (GT) extracts had led to an increase in their concomitant use with anticancer agents. GS and GT extracts were demonstrated to be potent inhibitors of CYP3A4. The aim of this study is to investigate the effect of standardized GS and/or GT extracts at two different doses on the pharmacokinetics of imatinib and its metabolite, N-desmethyl imatinib, in SD-rats.

METHODS

Standardized GS and/or GT extracts were administered orally once daily for 21 days, at low (l) and high (h) doses, 50 and 100 mg/kg, respectively, before the administration of a single intragastric dose of imatinib. Plasma samples were collected and analyzed for imatinib and N-desmethyl imatinib concentrations using LC-MS/MS method, then their non-compartmental pharmacokinetic parameters were determined.

RESULTS

h-GS dose significantly decreased imatinib's Cmax and the [Formula: see text] by 61.1 and 72.2%, respectively. Similar effects on N-desmethyl imatinib's exposure were observed as well, in addition to a significant increase in its clearance by 3.7-fold. l-GT caused a significant decrease in imatinib's Cmax and [Formula: see text] by 53.6 and 63.5%, respectively, with more significant effects on N-desmethyl imatinib's exposure, which exhibited a significant decrease by 79.2 and 81.1%, respectively. h-GT showed similar effects as those of l-GT on the kinetics of imatinib and its metabolite. However, when these extracts were co-administered at low doses, no significant effects were shown on the pharmacokinetics of imatinib and its metabolite. Nevertheless, increasing the dose caused a significant decrease in Cmax of N-desmethyl imatinib by 71.5%.

CONCLUSIONS

These results demonstrated that the pharmacokinetics of imatinib and N-desmethyl imatinib had been significantly affected by GS and/or GT extracts, which could be partially explained by the inhibition of CYP3A-mediated metabolism. However, the involvement of other kinetic pathways such as other isoenzymes, efflux and uptake transporters could be involved and should be characterized.

Grape Seed Proanthocyanidin Extract Prevents Bone Loss via Regulation of Osteoclast Differentiation, Apoptosis, and Proliferation

Dietary procyanidin has been shown to be an important bioactive component that regulates various pharmacological activities to maintain metabolic homeostasis. In particular, grape seed proanthocyanidin extract (GSPE) is a commercially available medicine for the treatment of venous and lymphatic dysfunction. This study aimed to investigate whether GSPE protects against lipopolysaccharide (LPS)-induced bone loss in vivo and the related mechanism of action in vitro. The administration of GSPE restored the inflammatory bone loss phenotype stimulated by acute systemic injection of LPS in vivo. GSPE strongly suppressed receptor activator of nuclear factor kappa-B ligand (RANKL)-induced osteoclast differentiation and bone resorption activity of mature osteoclasts by decreasing the RANKL-induced nuclear factor-κB transcription activity. GSPE mediates this effect through decreased phosphorylation and degradation of NF-κB inhibitor (IκB) by IκB kinaseβ, subsequently inhibiting proto-oncogene cellular Fos and nuclear factor of activated T cells. Additionally, GSPE promotes osteoclast proliferation by increasing the phosphorylation of components of the Akt and mitogen-activated protein kinase signaling pathways and it also inhibits apoptosis by decreasing the activity of caspase-8, caspase-9, and caspase-3, as corroborated by a decrease in the Terminal deoxynucleotidyl transferase dUTP nick end labeling -positive cells. Our study suggests a direct effect of GSPE on the proliferation, differentiation, and apoptosis of osteoclasts and reveals the mechanism responsible for the therapeutic potential of GSPE in osteoclast-associated bone metabolism disease.

Grape Seed Proanthocyanidin Extract Mitigates Titanium Dioxide Nanoparticle (TiO2-NPs)-Induced Hepatotoxicity Through TLR-4/NF-κB Signaling Pathway

With the progress of nanotechnology, the adverse effects of nanoscale materials are receiving much attention. Inhibition of toll-like receptor 4 (TLR-4)/nuclear factor kappa B (NF-κB) signaling is a hallmark for downregulating the expression of many inflammatory genes implicated in oxidative stress. Therefore, the present study aimed to demonstrate the influence of grape seed proanthocyanidin extract (GSE) on the hepatic TLR-4/ NF-κB signaling pathway in TiO₂-NP-induced liver damage in rats. Forty male Albino rats were divided into 4 groups (n = 10): G1 was used as a control, G2 received TiO₂-NPs (500 mg/kg/day orally) from the 17th to 30th day (acute toxicity), G3 received GSE (75 mg/kg/day orally) for 30 days, and G4 pre- and co-treated with GSE (for 30 days) and TiO₂-NPs (from the 17th to 30th day), with the aforementioned doses. TiO₂-NPs induced severe hepatic injury that was indicated by biochemical alterations in serum liver markers (acetylcholinesterase, ALT, ALP, total proteins, albumin, and direct bilirubin), oxidative stress indicators (MDA, GSH, and catalase), and histopathological alterations as well. Moreover, TiO₂-NPs triggered an inflammatory response via the upregulation of TLR-4, NF-κB, NIK, and TNF-α mRNA expressions. Pre- and co-treatments with GSE alleviated the detrimental effects of TiO₂-NPs which were enforced by the histopathological improvements. These results indicated that GSE effectively protected against TiO₂-NP-induced hepatotoxicity via the inhibition of TLR-4/NF-κB signaling and hence suppressed the production of pro inflammatory cytokines such as TNF-α and improved the antioxidant status of the rats.

Effects of grape seed extract on performance, immunity, antioxidant capacity, and meat quality in Pekin ducks

This study was conducted to evaluate the effects of grape seed extract (GSE) on growth performance, immunity, antioxidant capacity, relative organ weight, jejunum morphology, ileal microflora, and meat quality in Pekin ducks. A total of 1,500 female 1-day-old Pekin ducklings (52.0 ± 0.2 g) were blocked based on body weight (BW) and randomly allocated into 3 treatments with 10 replicates of 50 birds each. The experiment lasted for 6 wk, and dietary treatments included corn-soybean meal-based diet supplemented with 0, 0.01, and 0.02% GSE. The supplementation of GSE increased (P < 0.05) body weight gain (BWG) and final BW linearly but decreased (P < 0.05) feed-to-gain ratio (F/G) linearly during day (D) 22 to 42 and the entire experiment. The inclusion of GSE increased (P < 0.05) serum superoxide dismutase, glutathione peroxidase, total antioxidative capacity, catalase, complement4, immunoglobin G, interleukin-2, and interferon-γ linearly but decreased (P < 0.05) serum malondialdehyde linearly. The relative weight of carcass, breast meat, and spleen in GSE treatments was increased (P < 0.05) linearly, whereas the relative weight of abdominal fat was decreased linearly (P < 0.05). Birds fed GSE1 and GSE2 diets had lower (P < 0.05) cook loss, 2-thiobarbituric acid reactive substances, and drip loss on day 3 and 5 linearly but higher (P < 0.05) pH24h and water-holding capacity. The addition of GSE decreased (P < 0.05) jejunum crypt depth and ileal Escherichia coli counts linearly but increased (P < 0.05) jejunum villus height: crypt depth ratio and ileal Lactobacilli linearly. Taken together, the inclusion of GSE increased final BW and BWG, decreased F/G during day 22 to 42 and day 1 to 42, partially improved antioxidant activities, immunity, meat quality, and gut health in Pekin ducks.

Alleviation Effect of Grape Seed Proanthocyanidins on Neuronal Apoptosis in Rats with Iron Overload

We aimed to evaluate the effect of grape seed proanthocyanidins (GSPCs) on neuronal apoptosis, particularly through their roles in maintaining divalent mineral element balance and resisting oxidation in rats with iron overload. A total of 40 Sprague-Dawley rats were randomly divided into control, iron overload, GSPCs, and iron overload + GSPCs groups. The iron, calcium, zinc, magnesium, and copper contents in the brain tissue of the rats were measured using inductively coupled plasma mass spectrometry. Their oxidative stress state was determined using the relevant kit. The number of apoptotic neurons was evaluated using the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, and synaptosome numbers were determined using the immunohistochemical approach. Fas, Bax, and Bcl-2 gene expressions in the cortex and hippocampus were detected using quantitative real-time polymerase chain reaction. After 7 weeks, compared with the control group, the zinc and magnesium contents; superoxide dismutase, glutathione peroxidase, and catalase activities; and synaptophysin and Bcl-2 gene expressions in the iron overload group were significantly decreased, whereas the iron, calcium contents, and malondialdehyde contents; TUNEL-positive cell numbers; and Fas and Bax gene expressions were significantly increased. There were no significant changes in the copper content. Conversely, the rats exhibited better recovery when GSPCs were used instead of iron alone. In summary, GSPCs protected against iron overload induced neuronal apoptosis in rats by maintaining the divalent mineral element balance, reducing oxidative stress, and regulating apoptotic genes expressions.

Long-Lasting Effects of GSPE on Ileal GLP-1R Gene Expression Are Associated with a Hypomethylation of the GLP-1R Promoter in Female Wistar Rats

Flavonoids have been shown to modulate GLP-1 in obesity. GLP-1 induces some of its effects through the intestinal GLP-1 receptor (GLP-1R), though no data exist on how flavonoids affect this receptor. Here, we examine how a dose of grape seed proanthocyanidin extract (GSPE) with anti-obesity activity affects intestinal GLP-1R and analyze whether epigenetics play a role in the long-lasting effects of GSPE. We found that 10-day GSPE administration prior to the cafeteria diet upregulated GLP-1R mRNA in the ileum 17 weeks after the GSPE treatment. This was associated with a hypomethylation of the GLP-1R promoter near the region where the SP1 transcription factor binds. In the colon, the cafeteria diet upregulated GLP-1R without showing any GSPE effect. In conclusion, we have identified long-lasting GSPE effects on GLP-1R gene expression in the ileum that are partly mediated by hypomethylation at the gene promoter and may affect the SP1 binding factor.

Effects of Grape Seed Proanthocyanidin Extract on Vascular Endothelial Function in Participants with Prehypertension: A Randomized, Double-Blind, Placebo-Controlled Study

This study aimed to investigate the effects of grape seed proanthocyanidin extract (GSPE) on blood pressure and vascular endothelial function in middle-aged Japanese adults with prehypertension. We conducted a randomized, double-blind, placebo-controlled study on 6 men and 24 women aged 40-64 years old. The participants were randomized to receive tablets containing either low-dose (200 mg/day) or high-dose (400 mg/day) GSPE, or placebo, for 12 weeks. Systolic and diastolic blood pressures (SBP and DBP, respectively), brachial flow-mediated dilation (FMD), and other cardiovascular parameters were measured before and after 4, 8, and 12 weeks of treatment. The mean SBP in the high-dose group significantly decreased by 13 mmHg after 12 weeks (P = 0.028), although FMD did not change. In an ad hoc analysis of non-smoking participants (n = 21), the mean SBP, DBP, stiffness parameter β, distensibility, incremental elastic modulus (Einc), and pulse wave velocity (PWV) also significantly improved in the high-dose group after 12 weeks. Changes in Einc and PWV from baseline to 12 weeks were significantly greater in the high-dose group than in the placebo group (Einc, P = 0.023; PWV, P = 0.03). GSPE consumption could help maintain vascular elasticity and normal blood pressure in this population.

A Pilot Study of a Grape Seed Procyanidin Extract for Lung Cancer Chemoprevention

Grape seed procyanidin extract (GSE) had been reported to exert antineoplastic properties in preclinical studies. A modified phase I, open-label, dose-escalation clinical study was conducted to evaluate the safety, tolerability, MTD, and potential chemopreventive effects of leucoselect phytosome (LP), a standardized GSE complexed with soy phospholipids to enhance bioavailability, in heavy active and former smokers. Eight subjects ages 46-68 years were enrolled into the study and treated with escalating oral doses of LP for 3 months. Bronchoscopies with bronchoalveolar lavage and bronchial biopsies were performed before and after 3 months of LP treatment. Hematoxylin and eosin stain for histopathology grading and IHC examination for Ki-67 proliferative labeling index (Ki-67 LI) were carried out on serially matched bronchial biopsy samples from each subject to determine responses to treatment. Two subjects were withdrawn due to issues unrelated to the study medication, and a total of 6 subjects completed the full study course. In general, 3 months of LP, reaching the highest dose per study protocol was well tolerated and no dosing adjustment was necessary. Such a treatment regimen significantly decreased bronchial Ki-67 LI by an average of 55% (P = 0.041), with concomitant decreases in serum miR-19a, -19b, and -106b, which were oncomirs previously reported to be downregulated by GSE, including LP, in preclinical studies. In spite of not reaching the original enrollment goal of 20, our findings nonetheless support the continued clinical translation of GSE as an antineoplastic and chemopreventive agent against lung cancer.

Effect of grape seed proanthocyanidin extract on hard exudates in patients with non-proliferative diabetic retinopathy

PURPOSE

To evaluate the efficacy and safety of orally administered grape seed proanthocyanidin extract (GSPE) in patients with non-proliferative diabetic retinopathy (NPDR).

METHODS

In this randomized (1:2:2), multicentre, double-blind trial, patients (n = 124; age: 40-78 years) were administered placebo, calcium dobesilate (CD; 750 mg/d), or GSPE (150 mg/d) orally for up to 12 months. All patients had retinal thickening with hard exudates (HEs) that met predefined criteria; the median best-corrected visual acuity was 0.8, as assessed using the Snellen visual acuity card. The main outcome measure was an improvement in HEs by at least 1 grade on a 10-grade severity scale. This was evaluated using fundus photography over 1 year.

RESULTS

The rate of improvement in the HE severity was higher in the GSPE group than in the CD group. No statistically significant difference existed among the study groups in optical coherence tomography parameters, such as central subfield macular thickness and total macular volume (TMV). However, in the GSPE group, TMV after 9 months of treatment was significantly decreased compared with that at baseline. The GSPE group showed a significantly greater improvement in HE severity than did the placebo or CD group. Four cases in the GSPE group and 2 in the CD group were determined to have developed potential treatment-related adverse reactions, which were all gastrointestinal in nature.

CONCLUSIONS

Oral GSPE therapy for 1 year improved HEs in patients with NPDR. The efficacy of GSPE for HEs was higher than that of oral CD in the study patients.

Lipophilic Grape Seed Proanthocyanidin Exerts Anti-Proliferative and Pro-Apoptotic Effects on PC3 Human Prostate Cancer Cells and Suppresses PC3 Xenograft Tumor Growth in Vivo

The in vitro antiprostate cancer activity of lipophilic grape seed proanthocyanidin (LGSP) against the PC3 cell line was evaluated by MTT assay, flow cytometry, and immunoblot analysis, and the in vivo antiprostate cancer effect was evaluated by a PC3-derived mouse xenograft model via oral gavage LGSP. Ki67 and cleaved caspase 3 immunostaining experiments were performed in tumor tissues. LGSP exhibited a strong inhibitory effect on PC3 cell proliferation by inducing apoptosis. Treatment with LGSP resulted in a G1 phase cell cycle arrest in PC3 cells, which was further confirmed by decreasing the expression of cyclin D1 and CDK 4 and increasing the expression of the tumor suppressors p21 and p27. Furthermore, activation of cleaved fragments of caspases 3, caspases 9, and PARP indicated that LGSP-induced apoptosis is caspase-dependent. Upstream of caspase cascade, LGSP increased the cytochrome c release in cytoplasm. After treatment with LGSP, the Bcl-2/Bax ratio also decreased in PC3 cells. In tumor studies, LGSP inhibited the growth of PC3-derived mouse xenografts by inhibiting tumor cell proliferation and inducing apoptosis. Our findings suggest that LGSP is an effective antiprostate cancer component and deserves further study.

Protective effect of grape seed and skin extract against high-fat diet-induced dyshomeostasis of energetic metabolism in rat lung

BACKGROUND

Obesity is currently one of the major epidemics of this millennium and affects poeples throughout the world. It causes multiple systemic complications as it significantly interferes with respiratory function.

OBJECTIVE

We aimed in the present work to study the effect of high fat diet (HFD) on lung oxidative stress and energy metabolism alterations, as well as the putative protection afforded by grape seed and skin extract (GSSE).

METHODS

We started by characterizing the GSSE and its composition using gas chromatography coupled to mass spectrometry (GC-MS). We used a rat model of high-fat-diet and we evaluated the effect of GSSE on oxidative stress and energetic disturbances induced by HFD. We analyzed the effect of HFD on lung oxidative status by assessing lipid oxidation level, non-protein thiols (NPSH) and superoxide anion level… We also evaluated the effect of HFD on creatine kinase (CK), malate dehydrogenase (MDH) and mitochondrial complex IV.

RESULTS

HFD induced body weight gain, increased lung weight and lipid content without affecting insulinemia and dropped adiponectemia. HFD also provoked on lung oxidative stress characterized by increased carbonylation (+ 95%; p = 0.0045), decreased of NPSH (- 32%; p = 0.0291) and inhibition of antioxidant enzyme activities such as glutathione peroxidase (- 25%; p = 0.0074). HFD also altered lung intracellular mediators as superoxide anion O2¯ (+ 59%; p = 0.0027) and increased lung xanthine oxidase activity (+ 27%; p = 0.0122). HFD induced copper depletion (- 24%; p = 0.0498) and lead (- 51%: p = 0.0490) from the lung. Correlatively HFD decreased the copper associated enzyme tyrosinase (- 29%; p = 0.0500) and decreased glutamine synthetase activity (- 31%; p = 0.0027). HFD altered also lung energy metabolism by increasing CK activity (+ 22%; p = 0.0108) and decreasing MDH and mitochondrial complex IV activities (- 28%; p = 0.0120, - 31%; p = 0.0086 respectively). Importantly all these alterations were efficiently corrected with GSSE treatment.

CONCLUSION

In conclusion, GSSE has the potential to alleviate the deleterious lipotoxic effect of HFD on lung and it could find potential application in the protection against HFD-induced lung complications.

Novel Antihypertensive Prodrug from Grape Seed Proanthocyanidin Extract via Acid-Mediated Depolymerization in the Presence of Captopril: Synthesis, Process Optimization, and Metabolism in Rats

Grape seed extract contains a high content of proanthocyanidins that can be depolymerized into C-4-substituted (epi)catechin derivatives in the presence of nucleophiles. However, the biological and medicinal values of depolymerization products have been rarely investigated. Recently, we developed a novel depolymerization product (-)-epicatechin-4β- S-captopril methyl ester (ECC) derived from the reaction of grape seed proanthocyanidin extract with captopril in the presence of acidified methanol. A central composite design was employed to select the most appropriate depolymerization temperature and time to obtain the target product ECC with a high yield. A total of 16 metabolites of ECC in rat urine, feces, and plasma were identified using liquid chromatography quadrupole time-of-flight tandem mass spectrometry. The in vivo results suggested that ECC could release captopril methyl ester and epicatechin, followed by the generation of further metabolites captopril and epicatechin sulfate conjugates. Therefore, ECC may be used as a potential prodrug with synergistic or additive hypotensive effects.

Effect of different concentrations and application times of proanthocyanidin gels on dentin erosion

PURPOSE

To analyze the effect of different concentrations and application times of proanthocyanidin gels on dentin before an erosive challenge in order to evaluate if there is a dose-response or application time-response relationship in the use of these gels for erosion prevention.

METHODS

80 bovine root dentin blocks were randomly and equally divided into 10 groups and treated according to the two factors under study (purified grape seed proanthocyanidin gel concentration and time of application): 0.05P1: 0.05% proanthocyanidin gel during 1 minute; 0.05P5: 0.05% proanthocyanidin gel during 5 minutes; 1P1: 1% proanthocyanidin gel during 1 minute; 1P5: 1% proanthocyanidin gel during 5 minutes; 5P1: 5% proanthocyanidin gel during 1 minute; 5P5: 5% proantho-cyanidin gel during 5 minutes; 10P1: 10% proanthocyanidin gel during 1 minute; 10P5: 10% proanthocyanidin gel during 5 minutes; Control 1: placebo gel during 1 minute; and Control 5: placebo gel during 5 minutes. The gels were applied over dentin blocks once before the first erosive challenge. After that, the blocks were subjected to three erosive cycles per day, during 5 days. Profilometry was used to quantify the dentin loss (µm). Data were analyzed by two-way ANOVA and Fisher's test (P< 0.05).

RESULTS

Statistical analysis showed that there was no significant difference between the application times. The different concentrations of proanthocianidin gels presented similar results (P> 0.05). All tested gels resulted in significantly less wear when compared to the placebo gel.

CLINICAL SIGNIFICANCE

Grape seed proanthocyanidin gels could be considered as a promising therapy to diminish erosive dentin wear because it may interact with the exposed collagen, enhancing the demineralized organic matrix stabilization, which acts as a barrier against the diffusion of the acids from erosion.

Resveratrol and Grape Extract-loaded Solid Lipid Nanoparticles for the Treatment of Alzheimer's Disease

The aggregation of amyloid-β peptide (Aβ) has been linked to the formation of neuritic plaques, which are pathological hallmarks of Alzheimer's disease (AD). Various natural compounds have been suggested as therapeutics for AD. Among these compounds, resveratrol has aroused great interest due to its neuroprotective characteristics. Here, we provide evidence that grape skin and grape seed extracts increase the inhibition effect on Aβ aggregation. However, after intravenous injection, resveratrol is rapidly metabolized into both glucuronic acid and sulfate conjugations of the phenolic groups in the liver and intestinal epithelial cells (within less than 2 h), which are then eliminated. In the present study, we show that solid lipid nanoparticles (SLNs) functionalized with an antibody, the anti-transferrin receptor monoclonal antibody (OX26 mAb), can work as a possible carrier to transport the extract to target the brain. Experiments on human brain-like endothelial cells show that the cellular uptake of the OX26 SLNs is substantially more efficient than that of normal SLNs and SLNs functionalized with an unspecific antibody. As a consequence, the transcytosis ability of these different SLNs is higher when functionalized with OX-26.

Defining Conditions for Optimal Inhibition of Food Intake in Rats by a Grape-Seed Derived Proanthocyanidin Extract

Food intake depends on homeostatic and non-homeostatic factors. In order to use grape seed proanthocyanidins (GSPE) as food intake limiting agents, it is important to define the key characteristics of their bioactivity within this complex function. We treated rats with acute and chronic treatments of GSPE at different doses to identify the importance of eating patterns and GSPE dose and the mechanistic aspects of GSPE. GSPE-induced food intake inhibition must be reproduced under non-stressful conditions and with a stable and synchronized feeding pattern. A minimum dose of around 350 mg GSPE/kg body weight (BW) is needed. GSPE components act by activating the Glucagon-like peptide-1 (GLP-1) receptor because their effect is blocked by Exendin 9-39. GSPE in turn acts on the hypothalamic center of food intake control probably because of increased GLP-1 production in the intestine. To conclude, GSPE inhibits food intake through GLP-1 signaling, but it needs to be dosed under optimal conditions to exert this effect.

Anti-hyperalgesic and anti-nociceptive potentials of standardized grape seed proanthocyanidin extract against CCI-induced neuropathic pain in rats

BACKGROUND

Neuropathic pain is associated with severe chronic sensory disturbances characterized by spontaneous pain, increased responsiveness to painful stimuli (hyperalgesia) and pain perceived in response to non-noxious stimuli (allodynia). Morphine is effective treatment for neuropathic pain but produces tolerance on chronic use. The present study was designed to explore the anti-nociceptive and anti-hyperalgesic effect of grape seed extract using sciatic nerve ligation-induced neuropathic pain in rats.

METHODS

Chronic constructive injury (CCI) was performed under anesthesia, on one side leg exposed by making a skin incision, and chromic gut ligatures were tied loosely around the sciatic nerve at 1 mm intervals. The treatment with grape seed proanthocyanidin extract (GSPE) (100 and 200 mg/kg, p.o.) was initiated on 7th day post-surgery and continued for next 14 days. Morphine (10 mg/kg, s.c.) alone and morphine in combination with GSPE (100 mg/kg, p.o.) were administered in CCI rats for 5 days starting from 7th day. On 3rd, 7th, 14th and 21st day, behavioral parameters (mechanical allodynia and thermal hyperalgesia) were assessed. Then the animals were killed on 22nd day and biochemical parameters [reduced glutathione (GSH), lipid peroxidation (LPO), catalase, nitrite, superoxide dismutase (SOD)] were assessed.

RESULTS

Ligation of the sciatic nerve significantly induced mechanical allodynia and thermal hyperalgesia and induces oxidative stress (increase in LPO and nitrite) and decline of anti-oxidant enzyme levels (catalase, SOD, GSH) in sciatic nerve homogenate. GSPE (100 and 200 mg/kg, p.o.) attenuated all the behavioural and biochemical parameters. Morphine also significantly reversed the symptoms of neuropathic pain but produced tolerance after 5 days. Further, co-treatment of GSPE (100 mg/kg) with morphine (10 mg/kg, s.c.) in CCI rats significantly reversed the morphine tolerance and enhanced its anti-hyperalgesic effect as compared to the morphine-alone-treated group.

CONCLUSIONS

In the present set of experiments, GSPE showed a significant anti-hyperalgesic and anti-nociceptive effect in rats.

The Protective Effect of Grape-Seed Proanthocyanidin Extract on Oxidative Damage Induced by Zearalenone in Kunming Mice Liver

Although grape-seed proanthocyanidin extract (GSPE) demonstrates strong anti-oxidant activity, little research has been done to clearly reveal the protective effects on the hepatotoxicity caused by zearalenone (ZEN). This study is to explore the protective effect of GSPE on ZEN-induced oxidative damage of liver in Kunming mice and the possible protective molecular mechanism of GSPE. The results indicated that GSPE could greatly reduce the ZEN-induced increase of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities. GSPE also significantly decreased the content of MDA but enhanced the activities of antioxidant enzymes SOD and GSH-Px. The analysis indicated that ZEN decreased both mRNA expression levels and protein expression levels of nuclear erythroid2-related factor2 (Nrf2). Nrf2 is considered to be an essential antioxidative transcription factor, as downstream GSH-Px, γ-glutamyl cysteine synthetase (γ-GCS), hemeoxygenase-1 (HO-1), and quinone oxidoreductase 1 (NQO1) decreased simultaneously, whereas the pre-administration of GSPE groups was shown to elevate these expressions. The results indicated that GSPE exerted a protective effect on ZEN-induced hepatic injury and the mechanism might be related to the activation of the Nrf2/ARE signaling pathway.

Cytoprotective effects of grape seed extract on human gingival fibroblasts in relation to its antioxidant potential

Cytoprotective effects of short-term treatment with grape seed extract (GSE) upon human gingival fibroblasts (hGFs) were evaluated in relation to its antioxidant properties and compared with those of a water-soluble analog of vitamin E: trolox (Tx). GSE and Tx showed comparable antioxidant potential in vitro against di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (DPPH; a stable radical), hydroxyl radical (^•OH), singlet oxygen (¹O₂), and hydrogen peroxide (H₂O₂). Pretreatment or concomitant treatment with GSE for 1 min protected hGFs from oxidative stressors, including H₂O₂, acid-electrolyzed water (AEW), and ¹O₂, and attenuated the intracellular formation of reactive oxygen species induced by H₂O₂ and AEW. Tx also reduced the H₂O₂- and AEW-induced intracellular formation of reactive oxygen species, but showed no cytoprotective effects on hGFs exposed to H₂O₂, AEW, or ¹O₂. These results suggest that the cytoprotective effects of GSE are likely exerted independently of its antioxidant potential.

[The effects of grape seed and coriander oil on biochemical parameters of oral fluid in patients with periodontitis]

Biochemical changes that are taking place in patients with periodontitis 1 and 2 the quality of the individuals place in a laqtatdegidrogenazis, alkaline phosphatase activity increase and reduced activity amilazais. Therefore we can conclude that, there is an increase in superoxide substances, which causes an increase in the oral cavity patobakteriebis and quality of periodontitis. The grape seed and coriander oil is of vegetable origin and antioxidant drugs. Their action causes a statistically significant increase in the amilazis, alkaline phosphatase and laqtatdegidrogenazis reduction, while the latter leads pH - rate of return to oral fluid. It should be noted that the positive effect of coriander oil, but less effective.

A rapid method to determine colonic microbial metabolites derived from grape flavanols in rat plasma by liquid chromatography-tandem mass spectrometry

This study describes the development and validation of a liquid chromatography-mass spectrometry method for determination of a large number of flavanol colonic derivatives in biological samples. The method was validated with rat plasma after the intake of grape seed flavanols. The minimum plasma volume necessary to maintain good recovery values within the range of 83-110% for all of the standards was determined by micro solid-phase extraction (μ-SPE). In total, 16 commercial standards were used to measure 30 different phenolic compounds present at low concentration levels (micromolar). The chromatographic method enabled reliable quantification of plasma colonic flavanol derivatives with low limits of detection and quantification, achieving values of 0.03 nM and 0.10 nM, respectively. The developed method can be readily applied to determine all of the flavanol metabolites that are most likely responsible for the majority of biological effects of poorly absorbed flavanols.

Dietary flavanols modulate the transcription of genes associated with cardiovascular pathology without changes in their DNA methylation state

Background

In a recent intervention study, the daily supplementation with 200 mg monomeric and oligomeric flavanols (MOF) from grape seeds for 8 weeks revealed a vascular health benefit in male smokers. The objective of the present study was to determine the impact of MOF consumption on the gene expression profile of leukocytes and to assess changes in DNA methylation.

Methodology/Principal Findings

Gene expression profiles were determined using whole genome microarrays (Agilent) and DNA methylation was assessed using HumanMethylation450 BeadChips (Illumina). MOF significantly modulated the expression of 864 genes. The majority of the affected genes are involved in chemotaxis, cell adhesion, cell infiltration or cytoskeleton organisation, suggesting lower immune cell adhesion to endothelial cells. This was corroborated by in vitro experiments showing that MOF exposure of monocytes attenuates their adhesion to TNF-α-stimulated endothelial cells. Nuclear factor kappa B (NF-κB) reporter gene assays confirmed that MOF decrease the activity of NF-κB. Strong inter-individual variability in the leukocytes' DNA methylation was observed. As a consequence, on group level, changes due to MOF supplementation could not be found.

Conclusion

Our study revealed that an 8 week daily supplementation with 200 mg MOF modulates the expression of genes associated with cardiovascular disease pathways without major changes of their DNA methylation state. However, strong inter-individual variation in leukocyte DNA methylation may obscure the subtle epigenetic response to dietary flavanols. Despite the lack of significant changes in DNA methylation, the modulation of gene expression appears to contribute to the observed vascular health effect of MOF in humans.

Grape seed procyanidin extract reduces the endotoxic effects induced by lipopolysaccharide in rats

Acute inflammation is a response to injury, infection, tissue damage, or shock. Bacterial lipopolysaccharide (LPS) is an endotoxin implicated in triggering sepsis and septic shock, and LPS promotes the inflammatory response, resulting in the secretion of proinflammatory and anti-inflammatory cytokines such as the interleukins (IL-6, IL-1β, and IL-10) and tumor necrosis factor-α by the immune cells. Furthermore, nitric oxide and reactive oxygen species levels increase rapidly, which is partially due to the activation of inducible nitric oxide synthase in several tissues in response to inflammatory stimuli. Previous studies have shown that procyanidins, polyphenols present in foods such as apples, grapes, cocoa, and berries, have several beneficial properties against inflammation and oxidative stress using several in vitro and in vivo models. In this study, the anti-inflammatory and antioxidant effects of two physiological doses and two pharmaceutical doses of grape seed procyanidin extract (GSPE) were analyzed using a rat model of septic shock by the intraperitoneal injection of LPS derived from Escherichia coli. The high nutritional (75mg/kg/day) and the high pharmacological doses (200mg/kg/day) of GSPE showed anti-inflammatory effects by decreasing the proinflammatory marker NOx in the plasma, red blood cells, spleen, and liver. Moreover, the high pharmacological dose also downregulated the genes Il-6 and iNos; and the high nutritional dose decreased the glutathione ratio (GSSG/total glutathione), further illustrating the antioxidant capability of GSPE. In conclusion, several doses of GSPE can alleviate acute inflammation triggered by LPS in rats at the systemic and local levels when administered for as few as 15 days before the injection of endotoxin.

Proanthocyanidin-rich grape seed extract reduces leg swelling in healthy women during prolonged sitting

BACKGROUND

Leg swelling is a modern-day affliction of sedentary working women. The aim of this study was to evaluate the effectiveness of the intake of grape seed extract (GSE) on leg swelling in healthy Japanese women while sitting.

RESULTS

Single intake trials and 14 day intake trials were held in a double-blind, placebo-controlled, crossover clinical study. A prolonged sedentary position was maintained for 6 h after GSE or placebo administration. Leg volume distension, increase in body extracellular fluid, and leg water were significantly suppressed in the GSE groups.

CONCLUSION

The intake of GSE is a contributing factor in the inhibition of leg swelling in healthy women during prolonged sitting.

Bioavailability of intact proanthocyanidins in the rat colon after ingestion of grape seed extract

Current evidence shows that monomeric flavonoids are known to be only slightly absorbed in the small intestine, but the metabolism of oligomeric and polymeric proanthocyanidins (PAC) in the colon is poorly understood. The objective of this study was to optimize the analysis of grape seed extract (GSE) in feces and use that method to assess the presence of PAC in the colon after ingestion of GSE. Rats were fed a diet ad libitum containing 0.25% (w/w) GSE for 10 days. Feces were collected daily and colonic contents at sacrifice on day 10, respectively. The recovery of fecal PAC using a solid-phase extraction (SPE) method was >70%. PAC were separated by normal-phase HPLC with fluorescence detection, and subsequent peak confirmation was done by MS-ion trap. The concentration of colonic contents at day 10 was 13.9 mg/kg for monomer, and those for oligomers (dimers-hexamers) were 33.4, 84.6, 87.2, 57.3, and 35.7 mg/kg, respectively. The concentration of monomeric and oligomeric PAC in daily feces was similar among days. In the mass balance analysis, approximately 11% of ingested PAC was recovered in the feces. These findings indicate that ingested PAC were present in the colon as the intact parent compounds and thus may contribute to the health of the gastrointestinal tract.

Effect of prophylactic supplementation with grape polyphenolics on endotoxin-induced serum secretory phospholipase A2 activity in rats

This study investigated whether dietary supplementation of polyphenolics-rich grape extract (GE) could attenuate endotoxin-induced serum secretory phospholipase A(2) (sPLA(2)) activity, a modulator of inflammation. Male Sprague-Dawley rats were fed a control diet or the diet supplemented with polyphenolic-rich GE (100 or 300 mg/kg daily) for 3 wk prior to intraperitoneal injection of 3 or 15 mg/kg LPS. A fluorometric assay was used to measure serum sPLA(2) activity during a 5-d period before and after LPS injection. Body weight, hematocrit, and serum C-reactive protein level were also measured. Administration of LPS induced a rapid increase in sPLA(2) activity, which peaked 1 to 2 d after LPS injection and resolved to near-baseline values on days 4 to 5. Marked declines in body weight and hematocrit, increases in C-reactive protein levels, and effects on health status also occurred. GE supplementation significantly attenuated the LPS-induced increase in sPLA(2) activity and decline in hematocrit, but its effects on the loss of body weight and C-reactive protein levels were not significant. Among the measurements, serum sPLA(2) was the only marker that showed a dose-dependent response to both LPS and GE supplementation. The current findings show that oral consumption of polyphenolic-rich GE suppresses endotoxin-induced sPLA(2) activity.

[Fatty acids of grape seed oil and its biological activity as 1,0% and 2,5% food-additive]

Using high-performance liquid chromatography were qualitatively and quantitatively identified high fatty acids contained in grape seed oil and compare its biological activity as 1,0% and 2,5% food-additive an fatty acids composition contained in lipids of mice livers. Investigation were carried out on 90 inbred mice 5,0 g weight. Using high-performance liquid chromatography methods in grape seed oil is identified linoleic (65,0%), linolenic (1,5%), oleic (17,0%), palmitic (8,0%), stearic (4,4%) and arachidonic (0,6%) acids. After 15 days fatty acids are carried out from mouse liver and individual identified. In paper is showed that 1,0% and 2,5% grape seed oil food-additive have a different biological activity. The investigation demonstrated that after 15 days the grape seed oil takes marked part in lipid metabolism of biological necessary components.

Grape seed proanthocyanidins inhibit the invasiveness of human HNSCC cells by targeting EGFR and reversing the epithelial-to-mesenchymal transition

Head and neck squamous cell carcinoma (HNSCC) is responsible for approximately 20,000 deaths per year in the United States. Most of the deaths are due to the metastases. To develop more effective strategies for the prevention of metastasis of HNSCC cells, we have determined the effect of grape seed proanthocyanidins (GSPs) on the invasive potential of HNSCC cell and the mechanisms underlying these effects using OSC19 cells as an in vitro model. Using cell invasion assays, we established that treatment of the OSC19 cells with GSPs resulted in a dose-dependent inhibition of cell invasion. EGFR is over-expressed in 90% of HNSCCs and the EGFR inhibitors, erlotinib and gefitinib, are being explored as therapies for this disease. We found that GSPs treatment reduced the levels of expression of EGFR in the OSC19 cells as well as reducing the activation of NF-κB/p65, a downstream target of EGFR, and the expression of NF-κB-responsive proteins. GSPs treatment also reduced the activity of ERK1/2, an upstream regulator of NF-κB and treatment of the cells with caffeic acid phenethyl ester, an inhibitor of NF-κB, inhibited cell invasion. Overexpression of EGFR and high NF-κB activity play a key role in the epithelial-to-mesenchymal transition, which is of critical importance in the processes underlying metastasis, and we found treatment with GSPs enhanced the levels of epithelial (E-cadherin, cytokeratins and desmoglein-2) and reduced the levels of mesenchymal (vimentin, fibronectin, N-cadherin and Slug) biomarkers in the OSC19 cells. These results indicate that GSPs have the ability to inhibit HNSCC cell invasion, and do so by targeting the expression of EGFR and activation of NF-κB as well as inhibiting the epithelial-to-mesenchymal transition.

Immunomodulatory and antitumor activities of grape seed proanthocyanidins

Proanthocyanidins are naturally occurring compounds that are widely available in many kinds of plants; particularly, the grape seeds are a rich source of proanthocyanidins. Grape seed proanthocyanidins (GSPs) have been demonstrated to possess a wide range of health beneficial properties. This study was carried out to elucidate the molecular mechanisms involved in the antitumor therapeutic and immunomodulating effects of GSPs through in vivo and in vitro models. The results showed that GSPs could significantly inhibit the growth of Sarcoma 180 tumor cells in vivo and remarkably increase thymus and spleen weight of Sarcoma 180-bearing mice and upgrade the secretion level of tumor necrosis factor-α (TNF-α) in serum. Moreover, GSPs could stimulate lymphocyte transformation, enhance lysosomal enzyme activity and phagocytic capability of peritoneal macrophages, and remarkably promote the production of TNF-α. These results suggested that GSPs could improve functional activation of the immune system, and the antitumor effects of GSPs were achieved by immunostimulating properties.

Grape proanthocyanidins induce apoptosis by loss of mitochondrial membrane potential of human non-small cell lung cancer cells in vitro and in vivo

Lung cancer remains the leading cause of cancer-related deaths worldwide, and non-small cell lung cancer (NSCLC) represents approximately 80% of total lung cancer cases. The use of non-toxic dietary phytochemicals can be considered as a chemotherapeutic strategy for the management of the NSCLC. Here, we report that grape seed proanthocyanidins (GSPs) induce apoptosis of NSCLC cells, A549 and H1299, in vitro which is mediated through increased expression of pro-apoptotic protein Bax, decreased expression of anti-apoptotic proteins Bcl2 and Bcl-xl, disruption of mitochondrial membrane potential, and activation of caspases 9, 3 and poly (ADP-ribose) polymerase (PARP). Pre-treatment of A549 and H1299 cells with the caspase-3 inhibitor (z-DEVD-fmk) significantly blocked the GSPs-induced apoptosis of these cells confirmed that GSPs-induced apoptosis is mediated through activation of caspases-3. Treatments of A549 and H1299 cells with GSPs resulted in an increase in G1 arrest. G0/G1 phase of the cell cycle is known to be controlled by cyclin dependent kinases (Cdk), cyclin-dependent kinase inhibitors (Cdki) and cyclins. Our western blot analyses showed that GSPs-induced G1 cell cycle arrest was mediated through the increased expression of Cdki proteins (Cip1/p21 and Kip1/p27), and a simultaneous decrease in the levels of Cdk2, Cdk4, Cdk6 and cyclins. Further, administration of 50, 100 or 200 mg GSPs/kg body weight of mice by oral gavage (5 d/week) markedly inhibited the growth of s.c. A549 and H1299 lung tumor xenografts in athymic nude mice, which was associated with the induction of apoptotic cell death, increased expression of Bax, reduced expression of anti-apoptotic proteins and activation of caspase-3 in tumor xenograft cells. Based on the data obtained in animal study, human equivalent dose of GSPs was calculated, which seems affordable and attainable. Together, these results suggest that GSPs may represent a potential therapeutic agent for the non-small cell lung cancer.

Improvement of mitochondrial function in muscle of genetically obese rats after chronic supplementation with proanthocyanidins

The aim of this study was to determine the effect of chronic dietary supplementation of a grape seed proanthocyanidin extract (GSPE) at a dose of 35 mg/kg body weight on energy metabolism and mitochondrial function in the skeletal muscle of Zucker obese rats. Three groups of 10 animals each were used: lean Fa/fa lean group (LG) rats, a control fa/fa obese group (OG) of rats, and an obese supplemented fa/fa proanthocyanidins obese group (POG) of rats, which were supplemented with a dose of 35 mg GSPE/kg of body weight/day during the 68 days of experimentation. Skeletal muscle energy metabolism was evaluated by determining enzyme activities, key metabolic gene expression, and immunoblotting of oxidative phosphorylation complexes. Mitochondrial function was analyzed by high-resolution respirometry using both a glycosidic and a lipid substrate. In muscle, chronic GSPE administration decreased citrate synthase activity, the amount of oxidative phosphorylation complexes I and II, and Nrf1 gene expression, without any effects on the mitochondrial oxidative capacity. This situation was associated with lower reactive oxygen species (ROS) generation. Additionally, GSPE administration enhanced the ability to oxidize pyruvate, and it also increased the activity of enzymes involved in oxidative phosphorylation including cytochrome c oxidase. There is strong evidence to suggest that GSPE administration stimulates mitochondrial function in skeletal muscle specifically by increasing the capacity to oxidize pyruvate and contributes to reduced muscle ROS generation in obese Zucker rats.

Effect of grape seed extract, Cistus ladanifer L., and vegetable oil supplementation on fatty acid composition of abomasal digesta and intramuscular fat of lambs

Thirty-six lambs were used in a 6 week experiment to evaluate the effect of vegetable oil blend supplementation (0 vs 60 g/kg of dry matter (DM)) and two dietary condensed tannin sources, grape seed extract (0 vs 25 g/kg of DM) and Cistus ladanifer L. (0 vs 250 g/kg of DM), on fatty acid (FA) composition of abomasal digesta and intramuscular polar and neutral lipids. Grape seed extract did not affect the FA profile of abomasal digesta or muscle lipid fractions. C. ladanifer had a minor effect in lambs fed diets with no oil but greatly changed the abomasal and muscle FA profiles in oil-supplemented lambs. It decreased 18:0 and increased 18:1 trans-11 in abomasal digesta and increased 18:1 trans-11 and 18:2 cis-9,trans-11 (P = 0.062) in muscle neutral lipids, resulting in an important enrichment of meat 18:2 cis-9,trans-11 when compared to other oil-supplemented diets (19.2 vs 41.7 mg/100 g of muscle).

Amelioration of tamoxifen-induced liver injury in rats by grape seed extract, black seed extract and curcumin

Liver injury was induced in female rats using tamoxifen (TAM). Grape seeds (Vitis vinifera) extract (GSE), black seed (Nigella sativa) extract (NSE), curcumin (CUR) or silymarin (SYL) were orally administered to TAM-intoxicated rats. Liver histopathology of TAM-intoxicated:rats showed pathological changes. TAM-intoxication elicited declines in liver antioxidant enzymes levels (glutathione peroxidase, glutathione reductase, superoxide dismutase and catalase), reduced glutathione (GSH) and GSH/GSSG ratio plus the hepatic elevations in lipid peroxides, oxidized glutathione (GSSG), tumor necrosis factor-alpha (TNF-alpha) and serum liver enzymes; alanine transaminase, aspartate transaminase, alkaline phosphatase, lactate dehydrogenase and gamma glutamyl transferase levels. Oral intake of NSE, GSE, CUR or SYL to TAM-intoxicated rats, attenuated histopathological changes and corrected all parameters mentioned above. Improvements were prominent in case of NSE (similarly SYL) > CUR > GSE. Data indicated that NSE, GSE or CUR act as free radicals scavengers and protect TAM-induced liver injury in rats.

Influence of dietary feeding of low monomer content grape seed extract on vitellogenin production and cholesterol levels in goldfish, Carassius auratus

Grape seed extract (GSE) is a source of naturally occurring compounds known as proanthocyanidins and flavan-3-ols, which are recognized to exert a protective effect on human health, so GSE is widely used mainly as a nutritional supplement. However, polyphenols may have, in some cases, estrogenic effects or may interfere with the endocrine system. For that reason, it was considered of interest to investigate the beneficial or detrimental effects induced by low monomer content grape seed extract (LMC-GSE) in a teleost experimental model, the juvenile goldfish (Carassius auratus); therefore, biomarkers of estrogenic exposure together with cholesterol titers were assessed in both plasma and tissue samples taken from fish fed with different doses of LMC-GSE for 4 weeks. Dietary LMC-GSE (71 or 35 mg/g diet) did not affect vitellogenin (VTG) synthesis; on the contrary, VTG production was exclusively induced in fish fed with an estradiol-17beta (E2)-incorporated diet. In addition, it was found that both plasma E2 levels and hepatic total cholesterol were not affected by LMC-GSE dietary regimens.