In Vitro Mechanistic Studies of a Standardized Sustainable Grape Seed Extract for Potential Application as a Mood-Modulating and Cognition-Enhancing Supplement.

BACKGROUND: Grape seed extract (GSE) from Vitis vinifera L. is rich in polyphenols and oligomeric proanthocyanidin complexes (OPCs), and it has shown potential benefits in managing low mood and cognitive function. In this study, we investigated the potential bioactivities of Enovita®, a standardized GSE extract (GSEe herein) rich in OPCs, in key mechanistic pathways related to low mood conditions and cognitive function. METHODS: In vitro assays were conducted to assess GSEe's inhibitory effects on γ-aminobutyric acid transaminase (GABA-T) and monoamine oxidase A (MAO-A), its binding affinity to the GABA site of GABA-A receptors, and its effects on acetylcholinesterase (AChE). Its neuroprotective effects on human SH-SY5Y neuroblastoma cells under oxidative stress (induced by H2O2) were assessed using MTT and LDH release assays. Its antioxidant activities were evaluated using DPPH, ABTS, FRAP, ORAC, HORAC, total phenolic content, and TAS assays. Its cytotoxicity was also evaluated. RESULTS: GSEe showed significant GABA-T inhibitory activity. It also exhibited MAO-A and AChE inhibition, along with moderate binding affinity to the GABA-A receptor. In neuroprotective assays, GSEe provided significant protection to SH-SY5Y cells against oxidative stress. GSEe demonstrated robust antioxidant activity in all assays, including scavenging of DPPH and ABTS radicals, high ferric-reducing power, high polyphenolic contents, and a substantial total antioxidant capacity. CONCLUSIONS: GSEe exhibits promising bioactivities, highlighting its potential as a supplement for modulating mood and enhancing cognitive function. Overall, the promising results from these in vitro studies provide a strong foundation for the continued exploration and development of GSEe as a viable natural supplement for enhancing mental health and cognitive function.

Effects of grape seed proanthocyanidin extract on cholesterol metabolism and antioxidant status in finishing pigs.

Grape seed proanthocyanidin extract (GSPE) is a natural polyphenolic compound, which plays an important role in anti-inflammatory and antioxidant. The present study aimed to investigate the effects of GSPE supplementation on the cholesterol metabolism and antioxidant status of finishing pigs. In longissimus dorse (LD) muscle, the data showed that GSPE significantly decreased the contents of total cholesterol (T-CHO) and triglyceride (TG), and decreased the mRNA expression of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoAR) and Fatty acid synthase (FAS), while increased the mRNA expression of carnitine palmitoyl transferase-1b (CPT1b), peroxisome proliferator-activated receptors (PPARα) and peroxisome proliferator activated receptor-γ coactivator-1α (PGC-1α). GSPE also reduced the enzyme activities of HMG-CoAR and FAS, and meanwhile amplified the activity of CPT1b in LD muscle of finishing pigs. Furthermore, dietary GSPE supplementation increased the serum catalase (CAT) and total antioxidant capacity (T-AOC), serum and liver total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-Px) levels, while reduced serum and liver malondialdehyde (MDA) level in finishing pigs. In the liver, Superoxide Dismutase 1 (SOD1), catalase (CAT), glutathione peroxidase 1 (GPX1), Nuclear Factor erythroid 2-Related Factor 2 (NRF2) mRNA levels were increased by GSPE. In conclusion, this study showed that GSPE might be an effective dietary supplement for improving cholesterol metabolism and antioxidant status in finishing pigs.

Determination of the combined effect of grape seed extract and cold atmospheric plasma on foodborne pathogens and their environmental stress knockout mutants.

The study aimed to explore the antimicrobial efficacy of grape seed extract (GSE) and cold atmospheric plasma (CAP) individually or in combination against L. monocytogenes and E. coli wild type (WT) and their isogenic mutants in environmental stress genes. More specifically, we examined the effects of 1% (wt/vol) GSE, 4 min of CAP treatment, and their combined effect on L. monocytogenes 10403S WT and its isogenic mutants ΔsigB, ΔgadD1, ΔgadD2, ΔgadD3, as well as E. coli K12 and its isogenic mutants ΔrpoS, ΔoxyR, and ΔdnaK. In addition, the sequence of the combined treatments was tested. A synergistic effect was achieved for all L. monocytogenes strains when exposure to GSE was followed by CAP treatment. However, the same effect was observed against E. coli strains, only for the reversed treatment sequence. Additionally, L. monocytogenes ΔsigB was more sensitive to the individual GSE and the combined GSE/CAP treatment, whereas ΔgadD2 was more sensitive to CAP, as compared to the rest of the mutants under study. Individual GSE exposure was unable to inhibit E. coli strains, and individual CAP treatment resulted in higher inactivation of E. coli in comparison to L. monocytogenes with the strain ΔrpoS appearing the most sensitive among all studied strains. Our findings provide a step toward a better understanding of the mechanisms playing a role in the tolerance/sensitivity of our model Gram-positive and Gram-negative bacteria toward GSE, CAP, and their combination. Therefore, our results contribute to the development of more effective and targeted antimicrobial strategies for sustainable decontamination.IMPORTANCEAlternative approaches to conventional sterilization are gaining interest from the food industry, driven by (i) the consumer demand for minimally processed products and (ii) the need for sustainable, environmentally friendly processing interventions. However, as such alternative approaches are milder than conventional heat sterilization, bacterial pathogens might not be entirely killed by them, which means that they could survive and grow, causing food contamination and health hazards. In this manuscript, we performed a systematic study of the impact of antimicrobials derived from fruit industry waste (grape seed extract) and cold atmospheric plasma on the inactivation/killing as well as the damage of bacterial pathogens and their genetically modified counterparts, for genes linked to the response to environmental stress. Our work provides insights into genes that could be responsible for the bacterial capability to resist/survive those novel treatments, therefore, contributing to the development of more effective and targeted antimicrobial strategies for sustainable decontamination.

Comparative Evaluation of Various Antioxidants on the Shear Bond Strength of Composite Resin to Bleached Enamel - An In Vitro Study.

AIM: To evaluate and compare the effect of various antioxidants on the shear bond strength of composite resin to bleached enamel. MATERIALS AND METHODS: Labial enamel surfaces of 90 extracted human maxillary central incisors were randomly divided into five groups based on the antioxidant used as follows: Group I ( n = 20): Bleaching with 40% hydrogen peroxide gel for 10 min, without the use of an antioxidant; Group II ( n = 20): Bleaching followed by the use of 10% sodium ascorbate solution; Group III ( n = 20): Bleaching followed by the use of 5% grape seed extract solution; Group IV ( n =20): Bleaching followed by the use of 5% pine bark extract solution; and Group V ( n =20): Control group in which no bleaching was done. Groups I-IV were further subdivided into two subgroups of 10 teeth each, whether the antioxidant application and composite build-up was done immediately (subgroup A) or after 2 weeks of postbleaching (subgroup B). Shear bond strength of the specimens was tested under a universal testing machine. RESULTS: One-way analysis of variance followed by Mann-Tukey posthoc multiple comparison test was used to analyse the data. The level of significance was established at P < 0.05. CONCLUSION: Within the limitations of this study, it was observed that the use of antioxidants effectively reversed the compromised bond strength of bleached enamel. Among the antioxidants, 5% pine bark extract application after bleaching showed better bond strength.

Evaluation of inhibitory activity of essential oils and natural extracts on foodborne viruses.

AIMS: Enteric viruses are recognized as a major concern in health care and in the food sector in Canada. Novel clean-label strategies for controlling enteric viruses are sought in the food industry. In this study, we examined the antiviral potential of plant extracts and essential oils on murine norovirus 1 (MNV-1), hepatitis A virus (HAV), and herpes simplex virus 1 (HSV-1). METHODS AND RESULTS: Inactivation of the viruses by grape seed, blueberry, green tea, and cranberry extracts and by rosemary and thyme essential oils was measured using plaque formation assay. Concentrations ranging from 50 to 200 000 ppm with a contact time of 90 min were tested. Grape seed extract at 10 000 ppm was the most effective (P < 0.05) at reducing MNV-1 and HAV infectious titers, respectively, by 2.85 ± 0.44 log10 and 1.94 ± 0.17 log10. HSV-1 titer was reduced by 3.81 ± 0.40 log10 at 1000 ppm grape seed extract. CONCLUSIONS: Among the plant products tested, grape seed extract was found the most effective at reducing the infectious titers of MNV-1, HAV, and HSV.

Sex Differences in the Absorption, Disposition, Metabolism, and Excretion of Grape Seed Proanthocyanidins in Prepubescent Rats.

SCOPE: The absorption, disposition, metabolism, and excretion (ADME) of phenolic compounds are key factors in determining their bioactivity. The group demonstrates that the ADME of a Grape Seed Proanthocyanidin Extract (GSPE) depends on sex in adult rats and specifically, methylated metabolites are only quantified in brain male adult rats. The aim of this study is to determine whether these differences exist before puberty. METHODS AND RESULTS: Prepubescent 4-week-old male and female Wistar rats are administered GSPE at a dose of 1000 mg kg-1. Plasma, liver, mesenteric white adipose tissue (MWAT), brain, and kidneys are extracted excised 2 h after GSPE administration, and the PAs metabolite profile is studied by HPLC-ESI-MS/MS. Moreover, plasma estradiol and brain and liver catechol-O-methyltransferase (COMT) protein levels are also studied. Results showed that there are no differences in plasma and brain among sexes and only differences are observed in liver, MWAT, and kidney with individual metabolites. This agrees with the lack of differences in estradiol and COMT levels among sexes. However, the ADME of PAs metabolites is higher in male rats. CONCLUSIONS: The results demonstrate lack of sex-dependence in metabolite profile in prepubescent rats, suggesting that sex differences in the metabolism of GSPE occur due to puberty.

Procyanidin B2-3'-O-Gallate Derived from Grape Seed Polymeric Procyanidins via the Galloyl-Attached Nucleophilic Degradation as a Potential Hepatoprotective Agent.

An effective method was developed for preparing galloylated procyanidins (GPCs) using galloyl-attached nucleophilic degradation. Under degradation conditions optimized through Box-Behnken design and single-factor experiments, two dimeric and three tetrameric GPCs were produced, with the yield of procyanidin B2-3'-O-gallate (B2-3'-G) reaching up to 232 mg/g (PPCs). The structure of B2-3'-G was identified by UV, FTIR, NMR, CD, MS, and phloroglucinolysis. Furthermore, the protective effect of B2-3'-G against alcohol-induced liver injury (ALI) was investigated. Compared with the parent compounds, B2-3'-G exhibited a stronger capacity for inhibiting ALI, attributed to its polymerization degree and galloyl group. Subsequent experiments revealed that the pretreatment of BRL-3A cells with B2-3'-G prior to ethanol improved ALI through activation of the Nrf2-HO-1/NQO1 pathway and initiation of enzymatic antioxidant systems. These findings suggest that GPC B2-3'-G is a potential hepatoprotective agent, which provides a new perspective for functional development of GPCs.

Time-of-Day Adrenal Modulation of Corticosterone Synthesis is Affected by Sex and Diet but Not by Proanthocyanidins in Rat.

SCOPE: The aim of this study is to investigate the effect of time-of-day on serum hormones and gene expression in adrenal glands, studying the impact of sex, obesogenic diet, and timing of proanthocyanidins administration, with a focus on glucocorticoids synthesis by this gland. METHODS AND RESULTS: Female and male rats, assigned to a standard chow or a cafeteria diet-fed group, receive a daily oral dose of a grape seed proanthocyanidin extract (GSPE), or a vehicle (when light is turned on, or when light is turned off). Corticosterone, estradiol, and testosterone serum levels, and the expression analysis of clock genes and genes related to corticosterone synthesis pathway, are assessed. Serum hormone levels exhibited a marked time-of-day effect also see in the expression of scavenger receptor class B member 1 (Scarb1) and cyp11b genes. The correlation between these two genes and period circadian regulator 2 (Per2) is also extended to other clock genes, although to a lesser extent: cryptochrome (Cry) and nuclear receptor subfamily 1 group D member 1 (Rev-erba). CONCLUSION: The strong correlations found suggest an important role of local Per2 (but also of Cry and Rev-erbA) in regulating the expression of the enzymes involved in the corticosterone synthesis pathway. The expression of clock genes in adrenals is influenced by sex and diet but not by GSPE.

Elevating Skincare Science: Grape Seed Extract Encapsulation for Dermatological Care.

The skin is the largest organ in the human body and serves multiple functions such as barrier protection and thermoregulation. The maintenance of its integrity and healthy structure is of paramount importance. Accordingly, technological advances in cosmetic sciences have been directed towards optimizing these factors. Plant-derived ingredients have been explored for their bioactivity profiles and sustainable sources. Grape by-products contain a group of bioactive molecules that display important biological activities. Nonetheless, many of these molecules (e.g., phenolic compounds) are unstable and susceptible to degradation. So, their encapsulation using nano/microsystems (i.e., microdispersions) has been explored as a promising solution. In this work, two grape seed extracts were obtained, one from a single grape variety (GSE-Ov) and another from a mix of five grape varieties (GSE-Sv). These extracts were analysed for their antioxidant and antimicrobial activities, as well as their chemical composition and molecular structure. The extract that showed the most promising properties was GSE-Ov with a DPPH IC50 of 0.079 mg mL-1. This extract was encapsulated in soy lecithin microdispersions coated with pectin, with an encapsulation efficiency of 88.8%. They showed an in vitro release of polyphenols of 59.4% during 24 h. The particles displayed a zeta potential of -20.3 mV and an average diameter of 13.6 µm. Microdispersions proved to be safe under 5 and 2.5 mg mL-1 in HaCaT and HDF cell models, respectively. Additionally, they demonstrated anti-inflammatory activity against IL-1α when tested at 2 mg mL-1. This work enabled the valorisation of a by-product from the wine industry by using natural extracts in skincare products.

Enzyme-esterified grape seed proanthocyanidin derivatives as novel lipid-lowering agents.

Grape seed proanthocyanidin (GSP), as a natural antioxidant, has great potential to be developed into a lipid-lowering agent, but its low lipophilicity and stability greatly limit its application. In this study, an enzymatic esterification strategy was developed to introduce fatty acid chains into GSP, resulting in the successful synthesis of a series of new GSP derivatives. The results showed that up to 85% conversion of GSP and 35% TAG inhibition rate of GSP derivatives were achieved. The structures of GSP derivatives were identified by UPLC-MS/MS, and seven derivatives were confirmed as catechin-3'-O-laurate, epicatechin-3'-O-laurate, epicatechin gallate-3″,5″-di-O-laurate, epicatechin gallate-3',3″,5″-tri-O-laurate, procyanidin B1-3',3″-di-O-laurate, procyanidin B2-3',3″-di-O-laurate and procyanidin C1-3',3″,3‴-tri-O-laurate by NMR. GSP derivatives exhibited higher inhibitory effects on lipid accumulation, intracellular TAG and TC than parent GSP. These results indicate that GSP derivatives have potential as lipid-lowering agents for utilization in the food industry.

Grape Seed Proanthocyanidin Extract Attenuates Cafeteria-Diet-Induced Liver Metabolic Disturbances in Rats: Influence of Photoperiod.

This study investigated the influence of photoperiod (day length) on the efficacy of grape seed proanthocyanidin extract (GSPE) in mitigating metabolic disorders in obese rats fed a cafeteria diet. Rats were exposed to standard (L12), long (L18), or short (L6) photoperiods and treated with GSPE or vehicle. In the standard photoperiod, GSPE reduced body weight gain (50.5%), total cholesterol (37%), and triglycerides (34.8%), while increasing the expression of hepatic metabolic genes. In the long photoperiod, GSPE tended to decrease body weight gain, increased testosterone levels (68.3%), decreased liver weight (12.4%), and decreased reverse serum amino acids. In the short photoperiod, GSPE reduced glycemia (~10%) and lowered triglyceride levels (38.5%), with effects modified by diet. The standard photoperiod showed the greatest efficacy against metabolic syndrome-associated diseases. The study showed how day length affects GSPE's benefits and underscores considering biological rhythms in metabolic disease therapies.

Effects of ultrasonic-assisted natural deep eutectic solvent on the extraction rate, stability and antifungal ability of polyphenols from Cabernet Sauvignon seeds.

Ultrasonic-assisted extraction using a natural deep eutectic solvent (UAE-NADES) is an efficient method for extracting grape seed polyphenols (GSPs). In this study, response surface methodology was used to optimize the extraction of GSPs with UAE-NADES, and the theoretical extraction rate of GSPs was 139.014 mg GAE/g, the actual extraction rate was 135.78 ± 1.3 mg GAE/g. A pseudo-second-order kinetic extraction fitting was established to simulate the extraction process and mechanism (R2 > 0.99). Analysis of antioxidant capacity, Fourier-infrared spectroscopy and scanning electron microscopy revealed that UAE-NADES works synergetically to maintain the stability of extracted GSPs. The results of high-performance liquid chromatography showed that catechin (41.14 mg/g) is the main component of GSPs in the extract. The UAE-NADES extraction of GSPs can inhibit the growth of Alternaria alternata at 0.25 mg GAE/g, while the GSPs extracted by other methods can effectively inhibit the growth of Alternaria alternata at 0.35 mg GAE/g. Thus, this study demonstrates that UAE-NADES is a high-efficiency means of extracting GSPs and, in a wider sense, is a promising extraction technology for the green utilization of waste resources.

Vitis Vinifera Seed Extract Versus Micronized Purified Flavonoid Fraction for Patients with Chronic Venous Disease: A Randomized Noninferiority Trial.

BACKGROUND: Venoactive drugs (VADs) based on Vitis vinifera extract are widely used in Korea. However, studies on the clinical effects and head-to-head comparisons with other groups of VADs are limited. This trial aimed to evaluate whether Vitis vinifera seed extract was noninferior to the micronized purified flavonoid fraction (MPFF) in relieving venous symptoms and improving quality of life in patients with chronic venous disease. METHODS: In this double-blind prospective randomized trial, patients from 13 hospitals, who were diagnosed with venous incompetence by duplex ultrasound and classified as clinical class 1, 2, or 3 in the Clinical, Etiological, Anatomical, and Pathophysiological classifications were enrolled. The primary outcome was the change in the Chronic Venous Disease Quality of Life Questionnaire (CIVIQ-20) score at 8 weeks from baseline. Secondary outcomes included changes in the Aberdeen Varicose Vein Questionnaire, visual analog scale, and Venous Clinical Severity Score at 4 and 8 weeks from baseline. Moreover, the change in leg circumferences was measured at 8 weeks and compared to baseline. RESULTS: In total, 303 patients were enrolled and randomly assigned to receive either Vitis vinifera seed extract (n = 154) or MPFF (n = 149). The CIVIQ-20 scores at 8 weeks were significantly reduced compared to those at baseline in both groups. No significant intergroup difference in the change of CIVIQ-20 at 8 weeks from baseline was observed (-8.31 ± 14.63 vs. -10.35 ± 14.38, P = 0.29, 95% confidence interval -1.65 to 5.72). The lower limit of the 95% confidence interval was within the predefined noninferiority margin of 6.9. Furthermore, the Aberdeen Varicose Vein Questionnaire, visual analog scale, and Venous Clinical Severity Score scores significantly decreased at 4 and 8 weeks after randomization compared with baseline in both groups. No significant differences were observed in the reduction of each score between groups. The calf circumference measured at 8 weeks was significantly reduced compared to that at baseline in patients receiving Vitis vinifera seed extract. CONCLUSIONS: Vitis vinifera seed extract was noninferior to MPFF in relieving venous symptoms and improving the quality of life in patients with chronic venous disease.

Grape seed extract protects rat offspring hippocampus from the silicon dioxide nanoparticles' neurotoxicity.

Silicon dioxide nanoparticles (SiO2-NPs) can be found in many products, such as composites, paints, ceramics, consumer products, and food additives. We recently demonstrated that via breastfeeding, SiO2-NPs transfer to the offspring's brain, interfering negatively with hippocampus development. In this work, we evaluated the protective effect of grape seed extract (GSE) against the adverse effects of SiO2-NPs. After delivery, animals were administered 25 mg/kg SiO2-NPs with/without GSE (300 mg/kg) for 20 days (from 2nd to 21st days post-delivery) by gavage. SiO2-NPs increased malondialdehyde concentration and decreased antioxidant activity in the offspring's hippocampi. The mean number of dark neurons (DNs) was significantly higher in the hippocampi of the SiO2-NPs group, whereas the mean number of DCX + cells was significantly lower than in the control group. The offspring in the SiO2-NPs groups had a weak cognitive performance in adulthood. Interestingly, these adverse effects of SiO2-NPs were alleviated in the GSE-treated groups. Therefore, GSE can attenuate the damaging effects of maternal exposure to SiO2-NPs during lactation.

Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus mutans: a systematic review of in vitro studies.

OBJECTIVE: To provide an overview of the available scientific evidence from in vitro studies regarding the effect induced by the flavonoids contained in grape seed extracts (GSE) and cranberry on the microbiological activity of Streptococcus mutans (S. mutans). METHODS: This systematic review was performed following the parameters of the PRISMA statement (Preferred Reporting Items for Systematic Reviews and Meta-Analysis). Electronic and manual searches were conducted using PubMed, ScienceDirect, Web of Science, EBSCO, and Cochrane databases. Reference lists of selected articles were reviewed to identify relevant studies. The search was not limited by year and was conducted solely in English. Eligible studies comprised publications describing in vitro studies that evaluated the effect of flavonoids derived from GSE and cranberry extracts on the microbiological activity of S. mutans. Common variables were identified to consolidate the data. Authors of this review independently screened search results, extracted data, and assessed the risk of bias. RESULTS: Of the 420 studies identified from the different databases, 22 publications were finally selected for review. The risk of bias was low in 13 articles and moderate in 9. The studies analyzed in this review revealed that cranberry extract has an inhibitory effect on the bacterial growth of S. mutans in ranges from 0.5 mg/mL to 25 mg/mL, and GSE exerts a similar effect from 0.5 mg/mL to 250 mg/mL. Additionally, the extracts or their fractions showed reduced biofilm formation capacity, decreased polymicrobial biofilm biomass, deregulation of glycosyltransferases (Gtf) B and C expression, and buffering of pH drop. In addition to adequate antioxidant activity related to polyphenol content. CONCLUSIONS: The overall results showed that the extracts of cranberry and grape seed were effective in reducing the virulence factors of the oral pathogen. According to the data, proanthocyanidins are the active components in cranberry and grape seed that effectively resist S. mutans. They can inhibit the formation of insoluble polysaccharides in the extracellular matrix and prevent glycan-mediated adhesion, cohesion, and aggregation of the proteins in S. mutans. This suggests that these natural extracts could play an important role in the prevention of cariogenic bacterial colonization, as well as induce a decrease in their microbiological activity.

Grape seed extract prevents oestrogen deficiency-induced bone loss by modulating the gut microbiota and metabolites.

Proanthocyanidin-rich grape seed extract (GSE) has been shown to have the potential to protect bones, although the underlying mechanism remains unknown. The current study aims to explore GSE's preventive and therapeutic impact on bone loss induced by oestrogen deficiency and the underlying mechanism through the gut microbiota (GM) and metabolomic responses. In oestrogen-deficient ovariectomized (OVX) mice, GSE ameliorated bone loss by inhibiting the expansion of bone marrow adipose tissue (BMAT), restoring BMAT lipolysis and promoting bone formation. GSE regulated OVX-induced GM dysbiosis by reducing the abundance of opportunistic pathogenic bacteria, such as Alistipes, Turicibacter and Romboutsia, while elevating the abundance of beneficial bacteria, such as Bifidobacterium. The modified GM primarily impacted lipid and amino acid metabolism. Furthermore, the serum metabolites of GSE exhibited a significant enrichment in lipid metabolism. In summary, GSE shows potential as a functional food for preventing oestrogen deficiency-induced bone loss by modulating GM and metabolite-mediated lipid metabolism.

Dietary supplementation with grape seed extract from Vitus vinifera prevents suppression of GABAergic protein expression in female Sprague Dawley trigeminal ganglion in a model of chronic temporomandibular joint disorder.

OBJECTIVE: To investigate cellular changes in protein expression in the trigeminal ganglion in an established preclinical chronic model of temporomandibular joint disorder (TMD) in response to grape seed extract (GSE) supplementation based on its beneficial use in preclinical chronic orofacial pain models. DESIGN: Three experimental conditions included female Sprague-Dawley rats as naïve controls, and animals subjected to neck muscle inflammation and prolonged jaw opening with and without daily supplementation of GSE in the drinking water prior to inflammation. Changes were evaluated in mechanical sensitivity to von Frey filaments and protein expression in the trigeminal ganglion of animals 14 days post jaw opening. RESULTS: Calcitonin-gene related peptide and protein kinase A, proteins positively associated with peripheral sensitization and enhanced nociception, did not show elevated expression at day 14 in the model compared to naïve or GSE supplemented animals. However, neuronal levels of glutamate decarboxylase (GAD) 65/67, which are enzymes responsible for the synthesis of the inhibitory neurotransmitter GABA that functions to suppress neuronal excitability, were significantly decreased on day 14 post jaw opening. Similarly, a significant decrease in neuronal expression of the GABA receptor subunits GABAB1 and GABAB2, but not GABAA, was observed in the TMD model. Importantly, GSE prevented suppression of GAD 65/67 and GABAB subunits, maintaining levels similar to naïve animals. CONCLUSION: Results from our study provide evidence of the downregulation of inhibitory GABAergic proteins in trigeminal ganglion neurons in a preclinical chronic TMD model and the benefits of GSE supplementation in preventing their suppression and maintaining normal levels.

Grape seed-derived procyanidins decreases neuropathic pain and nerve regeneration by suppression of toll-like receptor 4-myeloid differentiation factor-88 signaling.

Background: Recent studies have shown that peripheral nerve regeneration process is closely related to neuropathic pain. Toll-like receptor 4 (TLR4) signaling was involved in different types of pain and nerve regeneration. TLR4 induced the recruitment of myeloid differentiation factor-88 adaptor protein (MyD88) and NF-κB-depended transcriptional process in sensory neurons and glial cells, which produced multiple cytokines and promoted the induction and persistence of pain. Our study aimed to investigate procyanidins's effect on pain and nerve regeneration via TLR4-Myd88 signaling. Methods: Spinal nerve ligation (SNL) model was established to measure the analgesic effect of procyanidins. Anatomical measurement of peripheral nerve regeneration was measured by microscopy and growth associated protein 43 (GAP43) staining. Western blotting and/or immunofluorescent staining were utilized to detect TLR4, myeloid differentiation factor-88 adaptor protein (MyD88), ionized calcium-binding adapter molecule 1 (IBA1) and nuclear factor kappa-B-p65 (NF-κB-p65) expression, as well as the activation of astrocyte and microglia. The antagonist of TLR4 (LPS-RS-Ultra, LRU) were intrathecally administrated to assess the behavioral effects of blocking TLR4 signaling on pain and nerve regeneration. Result: Procyanidins reduced mechanical allodynia, thermal hyperalgesia and significantly suppressed the number of nerve fibers regenerated and the degree of myelination in SNL model. Compared with sham group, TLR4, MyD88, IBA1 and phosphorylation of NF-κB-p65 were upregulated in SNL rats which were reversed by procyanidins administration. Additionally, procyanidins also suppressed activation of spinal astrocytes and glial cells. Conclusion: Suppression of TLR4-MyD88 signaling contributes to the alleviation of neuropathic pain and reduction of nerve regeneration by procyanidins.

Slightly viscous dispersions of mucoadhesive polymers as vehicles for nasal administration of dopamine and grape seed extract-loaded solid lipid nanoparticles.

With the aim to find an alternative vehicle to the most used thermosensitive hydrogels for efficient nanotechnology-based nose-to-brain delivery approach for Parkinson's disease (PD) treatment, in this work we evaluated the Dopamine (DA) and the antioxidant grape seed-derived pro-anthocyanidins (Grape Seed Extract, GSE) co-loaded solid lipid nanoparticles (SLNs) put in slight viscous dispersions (SVDs). These SVDs were prepared by dispersion in water at low concentrations of mucoadhesive polymers to which SLN pellets were added. For the purpose, we investigated two polymeric blends, namely Poloxamer/Carbopol (PF-127/Carb) and oxidized alginate/Hydroxypropylmethyl cellulose (AlgOX/HPMC). Rheological studies showed that the two fluids possess Newtonian behaviour with a viscosity slightly higher that water. The pH values of the SVDs were mainly within the normal range of nasal fluid as well as almost no osmotic effect was associated to both SVDs. All the SVDs were capable to provide DA permeation through nasal porcine mucosa. Moreover, it was found that PF-127/Carb blend possesses penetration enhancer capability better than the Alg OX/HPMC combination. Flow cytometry studies demonstrated the uptake of viscous liquids incorporating fluorescent SLNs by human nasal RPMI 2650 cell in time-dependent manner. In conclusion, the SVD formulations may be considered promising alternatives to thermosensitive hydrogels strategy. Moreover, in a broader perspective, such SVD formulations may be also hopeful for treating various neurological diseases beyond PD treatment.

The effects of grape seed extract supplementation on cardiovascular risk factors, liver enzymes and hepatic steatosis in patients with non-alcoholic fatty liver disease: a randomised, double-blind, placebo-controlled study.

BACKGROUND: Despite the high antioxidant potential of grape seed extract (GSE), very limited studies have investigated its effect on non-alcoholic fatty liver disease (NAFLD). Therefore, this study was conducted with the aim of investigating the effect of GSE on metabolic factors, blood pressure and steatosis severity in patients with NAFLD. METHODS: In this double-blind randomized clinical trial study, 50 NAFLD patients were divided into two groups of 25 participants who were treated with 520 mg/day of GSE or the placebo group for 2 months. The parameters of glycemic, lipid profile, blood pressure and steatohepatitis were measured before and after the intervention. RESULTS: The GSE group had an average age of 43.52 ± 8.12 years with 15 women and 10 men, while the placebo group had an average age of 44.88 ± 10.14 years with 11 women and 14 men. After 2 months of intervention with GSE, it was observed that insulin, HOMA-IR, TC, TG, LDL-c, ALT, AST, AST/ALT, SBP, DBP and MAP decreased and QUICKi and HDL-c increased significantly (p-value for all < 0.05). Also, before and after adjustment based on baseline, the average changes indicated that the levels of insulin, HOMA-IR, TC, TG, LDL-c, SBP, DBP, MAP in the GSE group decreased more than in the control group (p for all < 0.05). Furthermore, the changes in HDL-c were significantly higher in the GSE group (p < 0.05). The between-groups analysis showed a significant decrease in the HOMA-ß and AST before and after adjustment based on baseline levels (p < 0.05). Moreover, the changes in QUICKi after adjustment based on baseline levels were higher in the GSE group than in the control group. Also, between-groups analysis showed that the severity of hepatic steatosis was reduced in the intervention group compared to the placebo group (P = 0.002). CONCLUSIONS: It seems that GSE can be considered one of the appropriate strategies for controlling insulin resistance, hyperlipidemia, hypertension and hepatic steatosis in NAFLD patients. TRIAL REGISTRATION: The clinical trial was registered in the Iranian Clinical Trial Registration Center (IRCT20190731044392N1). https://irct.behdasht.gov.ir/trial/61413 . (The registration date: 30/03/2022).