Trans-, cis-, and dihydro-resveratrol: a comparative study

Sustained-Release Microspheres of Cyclodextrin-Resveratrol Complex Using Fenugreek Galactomannan Hydrogels: A Green Approach to Phytonutrient Delivery

Food matrices are becoming increasingly complex with the impregnation of phytonutrients with health-beneficial pharmacological effects. Herein, we report the preparation, characterization, and functional application of soluble and stable microspheres of trans-resveratrol (t-RES) developed through a water-based green process involving cyclodextrin (CD) and fenugreek galactomannan (FG). Spectroscopic and thermodynamic calculations identified γ-CD as the best CD to form a stable cyclodextrin-resveratrol inclusion complex (CD-R, 49-fold enhanced solubility); however, it exhibited a burst release profile. The sustained release of resveratrol was achieved by further encapsulating the inclusion complex within the fenugreek galactomannan hydrogel scaffold by a gel-phase dispersion process, resulting in an amorphous powder (FG-CD-R) as evident from powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) studies. Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) studies confirmed the formation of the inclusion complex with no chemical alterations. When dissolved in water, FG-CD-R swelled and released stable cuboid structures with an average particle size of 500 ± 53 nm with a zeta potential of -52 ± 5.3 mV. FG-CD-R demonstrated a sustained-release profile upon in vitro release studies. Accelerated study demonstrated its stability for a shelf-life of two years. Further it was shown to be suitable for the preparation of transparent gummies with improved sensory attributes compared to unformulated t-RES. In summary, FG-CD-R is simple to prepare and easily scalable, providing a sustained-release t-RES with a natural, food-grade, and clean label status (non-genetically modified, allergen-free, vegan, and free from residual solvents) for nutritional applications.

Resveratrol-Loaded Polydimethylsiloxane-Silica Hybrid Materials: Synthesis, Characterization, and Antitumoral Activity

In this work, hybrid materials within the polydimethylsiloxane-silica (PDMS-SiO2) system, synthesized via the sol-gel method, were developed and characterized for their potential to incorporate and release the bioactive compound resveratrol (RES). RES was incorporated into the materials with a high loading efficiency (>75%) using the rotary evaporator technique. This incorporation induced the amorphization of RES, resulting in enhanced solubility and in vitro release when compared to the free polyphenolic compound. The release profiles displayed pH dependence, exhibiting notably faster release at pH 5.2 compared to pH 7.4. The gradual release of RES over time demonstrated an initial time lag of approximately 4 h, being well described by the Weibull model. In vitro cytotoxicity studies were conducted on human osteosarcoma cells (MG-63), revealing a concentration-dependent decrease in cell viability for RES-loaded samples (for concentrations >50 µg mL-1).

Genotoxic and genoprotective effects of phytoestrogens: a systematic review

Phytoestrogens are xenoestrogens found in plants with a myriad of health benefits. However, various studies reported the genotoxic effects of these substances. Thus, we reviewed in vitro and in vivo studies published in PubMed, Scopus, and Web of Science to evaluate the genotoxic and the genoprotective potential of phytoestrogens. Only studies written in English and intended to study commercially available phytoestrogens were included. The screening was performed manually. Moreover, the underlying mechanism of action of phytoestrogens was described. Around half of those studies (43%) reported genoprotective results. However, several studies revealed positive results for genotoxicity with specific model organisms and with dose/concentration dependence. The assessment of the selected articles showed substantial differences in the used concentrations and a biphasic response was recorded in some phytoestrogens. As far as we know, this is the first study to assess the genotoxic and genoprotective effects of phytoestrogens systematically.

Copolymeric Micelles of Poly(ε-caprolactone) and Poly(methacrylic acid) as Carriers for the Oral Delivery of Resveratrol

In this study, we report the development of a micellar system based on a poly(methacrylic acid)-b-poly(ε-caprolactone)-b-poly(methacrylic acid) triblock copolymer (PMAA16-b-PCL35-b-PMAA16) for the oral delivery of resveratrol. The micellar nanocarriers were designed to comprise a PCL core for solubilizing the poorly water-soluble drug and a hydrated PMAA corona with bioadhesive properties for providing better contact with the gastrointestinal mucosa. The micelles were first formed in an aqueous media via the solvent evaporation method and then loaded with resveratrol (72% encapsulation efficiency). Studies by transmission electron microscopy (TEM) and dynamic and electrophoretic light scattering (DLS and PALS) revealed a spherical shape, nanoscopic size (100 nm) and a negative surface charge (-30 mV) of the nanocarriers. Loading of the drug slightly decreased the hydrodynamic diameter (Dh) and increased the ƺ-potential of micelles. In vitro dissolution tests showed that 80% and 100% of resveratrol were released in 24 h in buffers with pH 1.2 and 6.8, respectively, whereas for the same time, not more than 10% of pure resveratrol was dissolved. A heat-induced albumin denaturation assay demonstrated the advantage of the aqueous micellar formulation of resveratrol, which possessed anti-inflammatory potential as high as that of the pure drug. Further, the micellar resveratrol (5 µM) exerted a strong protective effect and maintained viability of mucosa epithelial HT-29 cells in a co-cultural model, representing the production of inflammatory cytokines. For comparison, the pure resveratrol at the same concentration did not protect the damaged HT-29 cells at all. Thus, the present study revealed that the PMAA-b-PCL-b-PMAA copolymeric micelles might be considered appropriate nanocarriers for the oral delivery of resveratrol.

Therapeutic Potential and Predictive Pharmaceutical Modeling of Stilbenes in Cannabis sativa

Cannabis sativa is a plant used for recreational and therapeutic purposes; however, many of the secondary metabolites in the plant have not been thoroughly investigated. Stilbenes are a class of compounds with demonstrated anti-inflammatory and antioxidant properties and are present in cannabis. Many stilbenes present in cannabis have been investigated for their therapeutic effects. Fourteen stilbenes have been identified to be present in cannabis, all of which are structurally dihydrostilbenoids, with half possessing a prenylated moiety. The stilbenes summarized in this analysis show varying degrees of therapeutic benefits ranging from anti-inflammatory, antiviral, and anti-cancer to antioxidant effects. Many of the identified stilbenes have been researched to a limited extent for potential health benefits. In addition, predictive in silico modeling was performed on the fourteen identified cannabis-derived stilbenes. This modeling provides prospective activity, pharmacokinetic, metabolism, and permeability data, setting the groundwork for further investigation into these poorly characterized compounds.

Plant-Derived Nutraceuticals Involved in Body Weight Control by Modulating Gene Expression

Obesity is the most prevalent health problem in the Western world, with pathological body weight gain associated with numerous co-morbidities that can be the main cause of death. There are several factors that can contribute to the development of obesity, such as diet, sedentary lifestyle, and genetic make-up. Genetic predispositions play an important role in obesity, but genetic variations alone cannot fully explain the explosion of obesity, which is why studies have turned to epigenetics. The latest scientific evidence suggests that both genetics and environmental factors contribute to the rise in obesity. Certain variables, such as diet and exercise, have the ability to alter gene expression without affecting the DNA sequence, a phenomenon known as epigenetics. Epigenetic changes are reversible, and reversibility makes these changes attractive targets for therapeutic interventions. While anti-obesity drugs have been proposed to this end in recent decades, their numerous side effects make them not very attractive. On the other hand, the use of nutraceuticals for weight loss is increasing, and studies have shown that some of these products, such as resveratrol, curcumin, epigallocatechin-3-gallate, ginger, capsaicin, and caffeine, can alter gene expression, restoring the normal epigenetic profile and aiding weight loss.

Resveratrol activates CD8+ T cells through IL-18 bystander activation in lung adenocarcinoma

Resveratrol, a natural product, has demonstrated anti-tumor effects in various kinds of tumor types, including colon, breast, and pancreatic cancers. Most research has focused on the inhibitory effects of resveratrol on tumor cells themselves rather than resveratrol’s effects on tumor immunology. In this study, we found that resveratrol inhibited the growth of lung adenocarcinoma in a subcutaneous tumor model by using the β-cyclodextrin-resveratrol inclusion complex. After resveratrol treatment, the proportion of M2-like tumor-associated macrophages (TAMs) was reduced and tumor-infiltrating CD8T cells showed significantly increased activation. The results of co-culture and antibody neutralization experiments suggested that macrophage-derived IL-18 may be a key cytokine in the resveratrol anti-tumor effect of CD8T cell activation. The results of this study demonstrate a novel view of the mechanisms of resveratrol tumor suppression. This natural product could reprogram TAMs and CD8T effector cells for tumor treatment.

The Anticancer Potential of Plant-Derived Nutraceuticals via the Modulation of Gene Expression

Current studies show that approximately one-third of all cancer-related deaths are linked to diet and several cancer forms are preventable with balanced nutrition, due to dietary compounds being able to reverse epigenetic abnormalities. An appropriate diet in cancer patients can lead to changes in gene expression and enhance the efficacy of therapy. It has been demonstrated that nutraceuticals can act as powerful antioxidants at the cellular level as well as anticarcinogenic agents. This review is focused on the best studies on worldwide-available plant-derived nutraceuticals: curcumin, resveratrol, sulforaphane, indole-3-carbinol, quercetin, astaxanthin, epigallocatechin-3-gallate, and lycopene. These compounds have an enhanced effect on epigenetic changes such as histone modification via HDAC (histone deacetylase), HAT (histone acetyltransferase) inhibition, DNMT (DNA methyltransferase) inhibition, and non-coding RNA expression. All of these nutraceuticals are reported to positively modulate the epigenome, reducing cancer incidence. Furthermore, the current review addresses the issue of the low bioavailability of nutraceuticals and how to overcome the drawbacks related to their oral administration. Understanding the mechanisms by which nutraceuticals influence gene expression will allow their incorporation into an “epigenetic diet” that could be further capitalized on in the therapy of cancer.

Targeting microbiota-host interactions with resveratrol on cancer: Effects and potential mechanisms of action

Resveratrol (RSV) is a natural polyphenolic compound detected in grapes, berries, and red wine. The anticancer activities of RSV have been observed in vivo and in vitro studies. However, the pharmacology mechanism of RSV is confusing due to its low bioavailability. According to studies of the metabolic characteristics of RSV, the gut intestine is a crucial site of its health benefits. Dietary RSV exhibits a profound effect on the gut microbiota structure and metabolic function. In addition, emerging evidence demonstrates a protective effect of RSV metabolites against carcinogenesis. Therefore, to better understand the anticancer mechanisms of dietary RSV, it is vital to evaluate the role of RSV-microbiota-host interactions in cancer therapy. In this review, we summarized significant findings on the anticancer activities of RSV based on epidemiological, experimental and clinical studies involved in investigating the metabolic characteristics and the traditional anticancer mechanisms of RSV. Special attention is given to the putative mechanisms involving microbiota-host interactions, such as the modulation of gut microecology and the anticancer effects of RSV metabolites. The changes in microbiota-host interactions after RSV supplementation play vital roles in cancer prevention and thus offering a new perspective on nutritional interventions to treat cancer.

Applications of resveratrol in the treatment of gastrointestinal cancer

Natural product compounds have lately attracted interest in the scientific community as a possible treatment for gastrointestinal (GI) cancer, due to their anti-inflammatory and anticancer properties. There are many preclinical, clinical, and epidemiological studies, suggesting that the consumption of polyphenol compounds, which are abundant in vegetables, grains, fruits, and pulses, may help to prevent various illnesses and disorders from developing, including several GI cancers. The development of GI malignancies follows a well-known path, in which normal gastrointestinal cells acquire abnormalities in their genetic composition, causing the cells to continuously proliferate, and metastasize to other sites, especially the brain and liver. Natural compounds with the ability to affect oncogenic pathways might be possible treatments for GI malignancies, and could easily be tested in clinical trials. Resveratrol is a non-flavonoid polyphenol and a natural stilbene, acting as a phytoestrogen with anti-cancer, cardioprotective, anti-oxidant, and anti-inflammatory properties. Resveratrol has been shown to overcome resistance mechanisms in cancer cells, and when combined with conventional anticancer drugs, could sensitize cancer cells to chemotherapy. Several new resveratrol analogs and nanostructured delivery vehicles with improved anti-GI cancer efficacy, absorption, and pharmacokinetic profiles have already been developed. This present review focuses on the in vitro and in vivo effects of resveratrol on GI cancers, as well as the underlying molecular mechanisms of action.

Resveratrol ameliorates muscle atrophy in chronic kidney disease via the axis of SIRT1/FoxO1

Chronic kidney disease (CKD) is often associated with muscle atrophy. However, the underlying molecular mechanisms are still not well understood. Here, we treated 5/6-nephrectomized (5/6Nx) rats with resveratrol and found that this treatment greatly improves renal function as evidenced by reduced proteinuria and cystatin C. Moreover, resveratrol ameliorates renal fibrosis by reducing transforming growth factor β (TGF-β) and connective tissue growth factor (CTGF). Meanwhile, muscle atrophy in these 5/6Nx rats was largely attenuated by resveratrol. Immunoprecipitation revealed that SIRT1 physically interacts with FoxO1 in muscle, and this interaction was weakened in 5/6Nx rats. As a consequence, acetylated FoxO1 was increased in muscle of 5/6Nx rats. The application of resveratrol markedly reverses this trend. These data point out that SIRT1 is a key factor for linking renal disease and muscle atrophy. Indeed, both renal dysfunction and muscle atrophy were further aggravated by 5/6Nx in Sirt1^+/- mice. Taken together, our data indicate that SIRT1 plays a pivotal role in muscle atrophy in CKD, and FoxO1 might be a substrate of SIRT1 in this process. Furthermore, resveratrol, together with other agonists of SIRT1, may hold great therapeutic potentials for treating CKD and its related muscle atrophy.

Recent Developments of Nanostructures for the Ocular Delivery of Natural Compounds

Ocular disorders comprising various diseases of the anterior and posterior segments are considered as the main reasons for blindness. Natural products have been identified as potential treatments for ocular diseases due to their anti-oxidative, antiangiogenic, and anti-inflammatory effects. Unfortunately, most of these beneficial compounds are characterised by low solubility which results in low bioavailability and rapid systemic clearance thus requiring frequent administration or requiring high doses, which hinders their therapeutic applications. Additionally, the therapeutic efficiency of ocular drug delivery as a popular route of drug administration for the treatment of ocular diseases is restricted by various anatomical and physiological barriers. Recently, nanotechnology-based strategies including polymeric nanoparticles, micelles, nanofibers, dendrimers, lipid nanoparticles, liposomes, and niosomes have emerged as promising approaches to overcome limitations and enhance ocular drug bioavailability by effective delivery to the target sites. This review provides an overview of nano-drug delivery systems of natural compounds such as thymoquinone, catechin, epigallocatechin gallate, curcumin, berberine, pilocarpine, genistein, resveratrol, quercetin, naringenin, lutein, kaempferol, baicalin, and tetrandrine for ocular applications. This approach involves increasing drug concentration in the carriers to enhance drug movement into and through the ocular barriers.

Therapeutic potential of resveratrol in diabetic nephropathy according to molecular signaling

BACKGROUND

Diabetic nephropathy (DN) as a severe complication of diabetes mellitus (DM), is a crucial menace for human health and survival and remarkably elevates the healthcare systems' costs. Therefore, it is worth noting to identify novel preventive and therapeutic strategies to alleviate the disease conditions. Resveratrol, as a well-defined anti-diabetic/ antioxidant agent has capabilities to counteract diabetic complications. It has been predicted that resveratrol will be a fantastic natural polyphenol for diabetes therapy in the next few years.

OBJECTIVE

Accordingly, the current review aims to depict the role of resveratrol in the regulation of different signaling pathways that are involved in the reactive oxygen species (ROS) production, inflammatory processes, autophagy, and mitochondrial dysfunction, as critical contributors to DN pathophysiology.

RESULTS

The pathogenesis of DN can be multifactorial; hyperglycemia is one of the prominent risk factors of DN development that is closely related to oxidative stress. Resveratrol, as a well-defined polyphenol, has various biological and medicinal properties, including anti-diabetic, anti-inflammatory, and anti-oxidative effects.

CONCLUSION

Resveratrol prevents kidney damages that are caused by oxidative stress, enhances antioxidant capacity, and attenuates the inflammatory and fibrotic responses. For this reason, resveratrol is considered an interesting target in DN research due to its therapeutic possibilities during diabetic disorders and renal protection.

Effect of Resveratrol Treatment on Human Pancreatic Cancer Cells through Alterations of Bcl-2 Family Members

Pancreatic cancers are among of the most lethal types of neoplasms, and are mostly detected at an advanced stage. Conventional treatment methods such as chemotherapy or radiotherapy often do not bring the desired therapeutic effects. For this reason, natural compounds are increasingly being used as adjuvants in cancer therapy. Polyphenolic compounds, including resveratrol, are of particular interest. The aim of this study is to analyze the antiproliferative and pro-apoptotic mechanisms of resveratrol on human pancreatic cells. The study was carried out on three human pancreatic cancer cell lines: EPP85-181P, EPP85-181RNOV (mitoxantrone-resistant cells) and AsPC-1, as well as the normal pancreatic cell line H6c7. The cytotoxicity of resveratrol in the tested cell lines was assessed by the colorimetric method (MTT) and the flow cytometry method. Three selected concentrations of the compound (25, 50 and 100 µM) were tested in the experiments during a 48-h incubation. TUNEL and Comet assays, flow cytometry, immunocytochemistry, confocal microscopy, real-time PCR and Western Blot analyses were used to evaluate the pleiotropic effect of resveratrol. The results indicate that resveratrol is likely to be anticarcinogenic by inhibiting human pancreatic cancer cell proliferation. In addition, it affects the levels of Bcl-2 pro- and anti-apoptotic proteins. However, it should be emphasized that the activity of resveratrol was specific for each of the tested cell lines, and the most statistically significant changes were observed in the mitoxantrone-resistant cells.

Comparative Analysis of the Antitumor Activity of Cis- and Trans-Resveratrol in Human Cancer Cells with Different p53 Status

Resveratrol, a natural plant phytoalexin, is produced in response to fungal infection or- UV irradiation. It exists as an isomeric pair with cis- and trans-conformation. Whereas multiple physiological effects of the trans-form, including a pronounced anti-tumoral activity, are nowadays elucidated, much less knowledge exists concerning the cis-isomer. In our work, we analyzed the antiproliferative and cytotoxic properties of cis-resveratrol in four different human tumor entities in direct comparison to trans-resveratrol. We used human cell lines as tumor models for hepatocellular carcinoma (HCC; HepG2, Hep3B), colon carcinoma (HCT-116, HCT-116/p53(-/-)), pancreatic carcinoma (Capan-2, MiaPaCa-2), and renal cell carcinoma (A498, SN12C). Increased cytotoxicity in all investigated tumor cells was observed for the trans-isomer. To verify possible effects of the tumor suppressor p53 on resveratrol-induced cell death, we used wild type and p53-deleted or -mutated cell lines for every tested tumor entity. Applying viability and cytotoxicity assays, we demonstrated a differential, dose-dependent sensitivity towards cis- or trans-resveratrol among the respective tumor types.

Enhancing Bioavailability of Nutraceutically Used Resveratrol and Other Stilbenoids

Stilbenoids are interesting natural compounds with pleiotropic in vitro and in vivo activity. Their well-documented biological properties include anti-inflammatory effects, anticancer effects, effects on longevity, and many others. Therefore, they are nowadays commonly found in foods and dietary supplements, and used as a part of treatment strategy in various types of diseases. Bioactivity of stilbenoids strongly depends on different types of factors such as dosage, food composition, and synergistic effects with other plant secondary metabolites such as polyphenols or vitamins. In this review, we summarize the existing in vitro, in vivo, and clinical data from published studies addressing the optimization of bioavailability of stilbenoids. Stilbenoids face low bioavailability due to their chemical structure. This can be improved by the use of novel drug delivery systems or enhancers, which are discussed in this review. Current in vitro and in vivo evidence suggests that both approaches are very promising and increase the absorption of the original substance by several times. However, data from more clinical trials are required.

Cytotoxic and Proapoptotic Effects of Resveratrol in In Vitro Studies on Selected Types of Gastrointestinal Cancers

Cancer diseases are currently one of the greatest health challenges in clinical medicine worldwide. Classic methods of treatment often lead to numerous side effects, including the development of multidrug resistance. For this reason, increasing hope is being placed on compounds of natural origin, mainly due to their pleiotropic effect on different types of cells, protective effect on normal cells and toxic effect on cancerous ones. The most studied group are the polyphenolic compounds, which include resveratrol. The effectiveness of polyphenols in the treatment and prevention of many diseases, including cancer of various origins, has become the basis of many scientific studies. The anticancer effect of resveratrol has been demonstrated at all stages of the carcinogenesis process. Additionally, whether administered by itself or in combination with cytostatics, it may play a significant role in the process of reversing multidrug resistance. A review of the effects of resveratrol in in vitro conditions proves that it has a stronger or weaker antiproliferative and proapoptotic effect on the cells of certain neoplasms of the gastrointestinal tract. Despite the differences in the effect of this compound on different types of cancer, a similar tendency can be observed especially regarding the correlation between the concentration of the compound and the incubation time on the one hand and the antitumour effect on the other hand. The information included in this review may prove helpful in planning in vivo and clinical studies in the future.

The Use of Micro- and Nanocarriers for Resveratrol Delivery into and across the Skin in Different Skin Diseases-A Literature Review

In recent years, polyphenols have been extensively studied due to their antioxidant, anticancer, and anti-inflammatory properties. It has been shown that anthocyanins, flavonols, and flavan-3-ols play an important role in the prevention of bacterial infections, as well as vascular or skin diseases. Particularly, resveratrol, as a multi-potent agent, may prevent or mitigate the effects of oxidative stress. As the largest organ of the human body, skin is an extremely desirable target for the possible delivery of active substances. The transdermal route of administration of active compounds shows many advantages, including avoidance of gastrointestinal irritation and the first-pass effect. Moreover, it is non-invasive and can be self-administered. However, this delivery is limited, mainly due to the need to overpassing the stratum corneum, the possible decomposition of the substances in contact with the skin surface or in the deeper layers thereof. In addition, using resveratrol for topical and transdermal delivery faces the problems of its low solubility and poor stability. To overcome this, novel systems of delivery are being developed for the effective transport of resveratrol across the skin. Carriers in the micro and nano size were demonstrated to be more efficient for safe and faster topical and transdermal delivery of active substances. The present review aimed to discuss the role of resveratrol in the treatment of skin abnormalities with a special emphasis on technologies enhancing transdermal delivery of resveratrol.

Polyphenols in foods: Classification, methods of identification, and nutritional aspects in human health

Polyphenols widely exists in various foods, including main crops, fruits, beverages and some wines. Famous representatives of polyphenols, such as resveratrol in red wine, (-)-epigallocatechin gallate in green tea, chlorogenic acid in coffee, anthocyanins in colored fruits, procyanidins in grape seed have become hot research topics in food science and nutrition. There have been thousands of papers on the biochemistry, chemistry, nutritional values and population-based investigations of dietary polyphenols. In this chapter, we reviewed the published articles and database of dietary polyphenols to draw a profile for the classification, structural identification, and biological activities mainly based on enzymes, cell bioassay and animal models, as well as the population-based investigation results. The typical compound and its health benefits for each category of polyphenols was also introduced. The identification of dietary polyphenols could be solved by combined spectroscopy methods, of which the liquid chromatography tandem mass spectrometry is highlighted to greatly increase the efficiency on structural identification. Although the population-based investigation showed some controversial results for health benefits, the multi-functions of dietary polyphenols on preventing metabolic syndromes, various cancers and neurodegenerative disease have attracted much attention.

Resveratrol Delivery from Implanted Cyclodextrin Polymers Provides Sustained Antioxidant Effect on Implanted Neural Probes

Intracortical microelectrodes are valuable tools used to study and treat neurological diseases. Due in large part to the oxidative stress and inflammatory response occurring after electrode implantation, the signal quality of these electrodes decreases over time. To alleviate this response, resveratrol, a natural antioxidant which elicits neuroprotective effects through reduction of oxidative stress, was utilized. This work compares traditional systemic delivery of resveratrol to the novel cyclodextrin polymer (pCD) local delivery approach presented herein, both in vitro and in vivo. The pCD displayed an extended resveratrol release for 100 days, as well as 60 days of free radical scavenging activity in vitro. In vivo results indicated that our pCD delivery system successfully delivered resveratrol to the brain with a sustained release for the entire short-duration study (up to 7 days). Interestingly, significantly greater concentrations of resveratrol metabolites were found at the intracortical probe implantation site compared to the systemic administration of resveratrol. Together, our pilot results provide support for the possibility of improving the delivery of resveratrol in an attempt to stabilize long-term neural interfacing applications.

Deciphering the Role of Polyphenols in Sports Performance: From Nutritional Genomics to the Gut Microbiota toward Phytonutritional Epigenomics

The individual response to nutrients and non-nutrient molecules can be largely affected by three important biological layers. The gut microbiome can alter the bioavailability of nutrients and other substances, the genome can influence molecule kinetics and dynamics, while the epigenome can modulate or amplify the properties of the genome. Today the use of omic techniques and bioinformatics, allow the construction of individual multilayer networks and thus the identification of personalized strategies that have recently been considered in all medical fields, including sports medicine. The composition of each athlete’s microbiome influences sports performance both directly by acting on energy metabolism and indirectly through the modulation of nutrient or non-nutrient molecule availability that ultimately affects the individual epigenome and the genome. Among non-nutrient molecules polyphenols can potentiate physical performances through different epigenetic mechanisms. Polyphenols interact with the gut microbiota, undergoing extensive metabolism to produce bioactive molecules, which act on transcription factors involved in mitochondrial biogenesis, antioxidant systems, glucose and lipid homeostasis, and DNA repair. This review focuses on polyphenols effects in sports performance considering the individual microbiota, epigenomic asset, and the genomic characteristics of athletes to understand how their supplementation could potentially help to modulate muscle inflammation and improve recovery.

Role of Resveratrol in Transmitochondrial AMD RPE Cells

Resveratrol is a phytoalexin, stilbenoid compound with antioxidant properties attributable to its bioactive trans-resveratrol content. This study characterized the effects of over-the-counter (OTC) resveratrol nutritional supplements and a HPLC-purified resveratrol formulation, in human transmitochondrial age-related macular degeneration (AMD) retinal pigment epithelial (RPE) patient cell lines. These cell lines, which were created by fusing blood platelets obtained from dry and wet AMD patients with mitochondria-deficient (Rho0) ARPE-19 cells, had identical nuclei (derived from ARPE-19 cells) but different mitochondria that were derived from AMD patients. After resveratrol treatment, the levels of cell viability and reactive oxygen species production were measured. Results demonstrated that treatment with different resveratrol formulations improved cell viability and decreased reactive oxygen species generation in each AMD patient cell line. Although further studies are required to establish the cytoprotective potential of resveratrol under different physiological conditions, this novel study established the positive effects of OTC resveratrol supplements in macular degeneration patient cybrid cell lines in vitro.

Development of resveratrol-conjugated gold nanoparticles: interrelationship of increased resveratrol corona on anti-tumor efficacy against breast, pancreatic and prostate cancers

Background: As part of our continuing quest to enhance the efficacy of bioactive phytochemicals in cancer therapy, we report an innovative green nanotechnology approach toward the use of resveratrol for the production of biocompatible resveratrol-conjugated gold nanoparticles (Res-AuNPs). Our overarching aim is to exploit the inherent pro-apoptotic properties of gold nanoparticles (AuNPs) through synergistic anti-tumor characteristics of resveratrol, with the aim of developing a new class of green nanotechnology-based phytochemical-embedded AuNPs for applications in oncology.

Method: Resveratrol was used to reduce Au³⁺ to Au⁰ for the synthesis of Res-AuNPs at room temperature and gum arabic (GA) was used to further encapsulate the nanoparticulate surface to increase the overall stability of the AuNPs. This comprehensive study involves the synthesis, full characterization and in vitro stability of Res-AuNPs in various biological media for their ultimate applications as anti-cancer agents against human breast (MDAMB-231), pancreatic (PANC-1) and prostate (PC-3) cancers.

Results: This strategy to systematically increase the corona of resveratrol on AuNPs, in order to gain insights into the interrelationship of the phytochemical corona on the overall anti-tumor activities of Res-AuNPs, proved successful. The increased resveratrol corona on Res-AuNPs showed superior anti-cancer effects, attributed to an optimal cellular uptake after 24-hour incubation, while GA provided a protein matrix support for enhanced trans-resveratrol loading onto the surface of the AuNPs.

Conclusion: The approach described in this study harnesses the benefits of nutraceuticals and nanoparticles toward the development of Res-AuNPs. We provide compelling evidence that the increased corona of resveratrol on AuNPs enhances the bioavailability of resveratrol so that therapeutically active species can be optimally available in vivo for applications in cancer therapy.

Natural products: An upcoming therapeutic approach to cancer

Cancer is one of the leading causes of death across the world. Different environmental and anthropogenic factors initiate mutations in different functional genes of growth factors and their receptors, anti-apoptotic proteins, self-renewal developmental proteins, tumor suppressors, transcription factors, etc. This phenomenon leads to altered protein homeostasis of the cell which in turn induces cancer initiation, development, progression and survival. From ancient times various natural products have been used as traditional medicine against different diseases. Natural products are readily applicable, inexpensive, accessible and acceptable therapeutic approach with minimum cytotoxicity. As most of the target-specific anticancer drugs failed to achieve the expected result so far, new multi-targeted therapies using natural products have become significant. In this review, we have summarized the efficacy of different natural compounds against cancer. They are capable of modulating cancer microenvironment and diverse cell signaling cascades; thus playing a major role in combating cancer. These compounds are found to be effective against several signaling pathways, mainly cell death pathways (apoptosis and autophagy) and embryonic developmental pathways (Notch pathway, Wnt pathway and Hedgehog pathway). This review article is expected to be helpful in understanding the recent progress of natural product research for the development of anticancer drug.

Resveratrol Modulates Desaturase Expression and Fatty Acid Composition of Cultured Hepatocytes

This study aimed to evaluate whether resveratrol (RSV) and its microbial metabolites dihydro-resveratrol (DHR) and lunularin (LUN) affected fatty acid metabolism and omega-3 polyunsaturated fatty acid (n3-PUFA) synthesis in cultured hepatocytes. To this end, cultured human HepG2 hepatocytes were treated with non-toxic concentrations of these polyphenols (40 μM) and Δ5- and Δ6-desaturase (FADS1 and FADS2, respectively) expression was measured. Resveratrol induced both genes but DHR and LUN showed no effect. Co-incubation of RSV with α-linolenic acid (ALA) also induced FADS1 and FADS2 expression. Moreover, transcription of carnitine palmitoyltransferase 1A and fatty acid synthase expression was increased, indicating induction of β-oxidation and fatty acid synthesis, respectively. Using gas chromatography to measure fatty acid levels, we observed the impact of RSV with and without ALA treatment on fatty acid composition. However, RSV reduced unsaturated while increasing saturated fatty acid levels. We found lower amounts of monounsaturated fatty acids (16:1n-7c, 18:1n-9c, 18:1n7c, and 20:1n-9) and n3-PUFA docosahexaenoic acid whereas unsaturated fatty acid levels, especially of stearic acid, were elevated. Of interest, once we co-incubated the cells with RSV together with bovine serum albumin, we found no differences in gene expression compared to cells without RSV treatment. Although we found no positive effect of RSV on n3-PUFA synthesis, the stilbene could possibly prevent cellular stress by decreasing unsaturated fatty acid levels.

Resveratrol: A Double-Edged Sword in Health Benefits

Resveratrol (3,5,4'-trihydroxy-trans-stilbene) belongs to polyphenols' stilbenoids group, possessing two phenol rings linked to each other by an ethylene bridge. This natural polyphenol has been detected in more than 70 plant species, especially in grapes' skin and seeds, and was found in discrete amounts in red wines and various human foods. It is a phytoalexin that acts against pathogens, including bacteria and fungi. As a natural food ingredient, numerous studies have demonstrated that resveratrol possesses a very high antioxidant potential. Resveratrol also exhibit antitumor activity, and is considered a potential candidate for prevention and treatment of several types of cancer. Indeed, resveratrol anticancer properties have been confirmed by many in vitro and in vivo studies, which shows that resveratrol is able to inhibit all carcinogenesis stages (e.g., initiation, promotion and progression). Even more, other bioactive effects, namely as anti-inflammatory, anticarcinogenic, cardioprotective, vasorelaxant, phytoestrogenic and neuroprotective have also been reported. Nonetheless, resveratrol application is still being a major challenge for pharmaceutical industry, due to its poor solubility and bioavailability, as well as adverse effects. In this sense, this review summarized current data on resveratrol pharmacological effects.

Modular pathway engineering for resveratrol and piceatannol production in engineered Escherichia coli

Resveratrol and its ortho-hydroxylated derivative piceatannol were biosynthesized by modular pathway engineering in Escherichia coli. The biosynthetic pathway was divided into three different modules. Module I includes polyketide biosynthetic genes; module II genes include acetyl-CoA and malonyl-CoA pool-enhancing genes from three different organisms; and module III genes are regiospecific 3'-hydroxylating enzymes. E. coli BL21(DE3) with module I produced 8.6 mg/L of resveratrol from exogenously fed 1 mM p-coumaric acid after 72 h. Combination of module I and acetyl-CoA supplementing module IIb genes from N. farcinica IFM10152 produced 2.5-fold higher (60 mg/L) titer of resveratrol than the module IIa genes from E. coli. The exogenous supplementation of sodium acetate further enhanced production to 64 mg/L. Furthermore, module I with module IIc harboring matBC from S. coelicolor A3(2) produced 73 mg/L of resveratrol, which was elevated to 151 mg/L upon supplementing disodium malonate exogenously. This increment is 17.5-fold higher than module I harboring E. coli BL21(DE3). The combination of module I and two different module II genes yielded 137 mg/L resveratrol when supplemented with both sodium acetate and disodium malonate. The high resveratrol-producing combination module was further modified with incorporation of hpaBC for the ortho-hydroxylation of resveratrol to produce piceatannol. The engineered strain harboring modules I, IIc and III produced 124 mg/L of piceatannol, the highest titer after 72 h in disodium malonate-supplemented strain, which is 2-fold higher than in non-supplemented strain. The remaining resveratrol was about 30 mg/L. Furthermore, caffeic acid (85.5 mg/L) was also produced in the same strain. Resveratrol and piceatannol were biosynthesized along with caffeic acid by three different modules overexpressing acetate and malonate assimilation pathway genes from three different sources. The production titer of both resveratrol and piceatannol could be achieved higher upon blocking acetyl-CoA and malonyl-CoA utilizing pathway genes in host strain.

Resveratrol and Related Stilbenoids, Nutraceutical/Dietary Complements with Health-Promoting Actions: Industrial Production, Safety, and the Search for Mode of Action

This paper reviews the potential of stilbenoids as nutraceuticals. Stilbenoid compounds in wine are considered key factors in health-promoting benefits. Resveratrol and resveratrol-related compounds are found in a large diversity of vegetal products. The stilbene composition varies from wine to wine and from one season to another. Therefore, the article also reviews how food science and technology and wine industry may help in providing wines and/or food supplements with efficacious concentrations of stilbenes. The review also presents results from clinical trials and those derived from genomic/transcriptomic studies. The most studied stilbenoid, resveratrol, is a very safe compound. On the other hand, the potential benefits of stilbene intake are multiple and are apparently due to downregulation more than upregulation of gene expression. The field may take advantage from identifying the mechanism of action(s) and from providing useful data to show evidence for specific health benefits in a given tissue or for combating a given disease.

Dosis Facit Sanitatem-Concentration-Dependent Effects of Resveratrol on Mitochondria

The naturally occurring polyphenol, resveratrol (RSV), is known for a broad range of actions. These include a positive impact on lifespan and health, but also pro-apoptotic anti-cancer properties. Interestingly, cell culture experiments have revealed a strong impact of RSV on mitochondrial function. The compound was demonstrated to affect mitochondrial respiration, structure and mass of mitochondria as well as mitochondrial membrane potential and, ultimately, mitochondria-associated cell death pathways. Notably, the mitochondrial effects of RSV show a very strict and remarkable concentration dependency: At low concentrations, RSV (<50 μM) fosters cellular antioxidant defense mechanisms, activates AMP-activated protein kinase (AMPK)- and sirtuin 1 (SIRT1)-linked pathways and enhances mitochondrial network formation. These mechanisms crucially contribute to the cytoprotective effects of RSV against toxins and disease-related damage, in vitro and in vivo. However, at higher concentrations, RSV (>50 μM) triggers changes in (sub-)cellular Ca²⁺ homeostasis, disruption of mitochondrial membrane potential and activation of caspases selectively yielding apoptotic cancer cell death, in vitro and in vivo. In this review, we discuss the promising therapeutic potential of RSV, which is most probably related to the compound’s concentration-dependent manipulation of mitochondrial function and structure.

RES-loaded pegylated CS NPs: for efficient ocular delivery

The objective of this study is to develop resveratrol (RES) loaded polyethylene glycols (PEGs) modified chitosan (CS) nanoparticles (NPs) by ionic gelation method for the treatment of glaucoma. While increasing the concentration of PEG, the particle size and polydispersity index of the formulations increased. Entrapment efficiency and RES loading (RL) of NPs decreased while increasing PEG concentration. The in vitro release of NPs showed an initial burst release of RES (45%) followed by controlled release. Osmolality of formulations revealed that the prepared NPs were iso-osmolar with the tear. Ocular tolerance of the NPs was evaluated using hen's egg test on the chorioallantoic membrane and it showed that the NPs were non-irritant. RES-loaded PEG-modified CS NPs shows an improved corneal permeation compared with RES dispersion. Fluorescein isothiocyanate loaded CS NPs accumulated on the surface of the cornea but the PEG-modified CS NPs crossed the cornea and reached retinal choroid. RES-loaded PEG-modified CS NPs reduced the intra-ocular pressure (IOP) by 4.3 ± 0.5 mmHg up to 8 h in normotensive rabbits. These results indicate that the developed NPs have efficient delivery of RES to the ocular tissues and reduce the IOP for the treatment of glaucoma.

Anti-proliferative and anti-metastasis effects of ten oligostilbenes from the seeds of Paeonia suffruticosa on human cancer cells

Paeonia suffruticosa from the section Moutan of the genus Paeonia is an important Chinese medicinal herb. In our previous study, 10 oligostilbenes from the seeds of P. suffruticosa, including trans-resveratrol and its dimers and trimers, were isolated and identified. In the present study, the anti-proliferative effects of these 10 oligostilbenes were systemically evaluated in a panel of human lung, breast and bone cancer cell lines, and their apoptotic effects were analyzed using a high-content multiplex apoptosis assay and a fluorescent caspase-3/7 assay. Furthermore, their anti-metastasis effects were examined in an invasive breast cancer cell line. Among the ten compounds, two resveratrol dimers, trans- and cis-gnetin H, showed the most potent anti-proliferative and anti-metastasis effects. All trans-oligostilbenes were more effective than their cis-forms, and trimers of resveratrol were more effective than dimers and the resveratrol isomer. The structure-activity relationships revealed that the polymerization degree, the double bond in the stilbene skeleton, and the steric arrangement and conformation of oligostilbenes obviously affected their antitumor potential. The results from this study provide valuable information for future semi-synthesis of resveratrol derivatives to develop novel cancer chemopreventive agents.

Co-encapsulated resveratrol and quercetin in chitosan and peg modified chitosan nanoparticles: For efficient intra ocular pressure reduction

Natural anti-oxidants resveratrol (RES) and quercetin (QUR) posses the ability to reduce intra ocular pressure efficiently. Concurrent administration of RES and QUR was able to enhance the bioavailability of RES. Present research work describes upsurge of QUR in RES loaded chitosan (CS) nanoparticles (NPs) and polyethylene glycol (PEG) modified CS NPs for improved delivery and synergic effects on reducing intra ocular pressure for the treatment of glaucoma. CS NPs and PEG modified CS NPs were prepared by ionic gelation of tripolyphosphate and CS. The synthesised NPs were spherical in shape and RES entrapment and loading efficiency in the formulation decreased with increasing PEG concentration. Particle size of the formulation increased while incorporating PEG and drugs. The crystalline nature of RES and QUR changed in the NPs and that was confirmed by XRD study. Free radical neutralising efficiency improved while incorporating QUR in the formulation. Ex-vivo corneal permeation of RES was higher from RES and QUR loaded formulation than RES alone containing NPs and free RES dispersion. RES and QUR loaded PEG modified CS NPs showed sustained and enhanced reduction of intra ocular pressure (5.5±0.5mmHg) in normotensive rabbits.

Dominant Carbons in trans- and cis-Resveratrol Isomerization

A comprehensive analysis for isomerization of geometric isomers in the case of resveratrol (R) has been presented. As an important red wine molecule, only one geometric isomer of resveratrol, i.e., trans-R rather than cis-R, is primarily associated with health benefit. In the present study, density function theory (DFT) provides accurate descriptions of isomerization of resveratrol. The nearly planar trans-R forms a relatively rigid and less flexible conjugate network, but the nonplanar cis-R favors a more flexible structure with steric through space interaction. The calculated carbon nuclear magnetic resonance (NMR) chemical shift indicates that all carbons are different in the isomers; it further reveals that four carbon sites, i.e., C₍₆₎, C₍₈₎═C₍₉₎, and C₍₁₁₎, have a significant response to the geometric isomerization. Here C₍₆₎ is related to the steric effect in cis-R, whereas C₍₁₁₎ may indicate the isomerization proton transfer on C₍₉₎ linking with the resorcinol ring. The excess orbital energy spectrum (EOES) confirms the NMR "bridge of interest" carbons and reveals that five valence orbitals of 34a, 35a, 46a, 55a, and 60a respond to the isomerization most significantly. The highest occupied molecular orbital (HOMO), 60a, of the isomer pair is further studied using dual space analysis (DSA) for its orbital momentum distributions, which exhibit p-electron dominance for trans-R but hybridized sp-electron dominance for cis-R. Finally, energy decomposition analysis (EDA) highlights that trans-R is preferred over cis-R by -4.35 kcal·mol^-1, due to small electrostatic energy enhancement of the attractive orbital energy with respect to the Pauli repulsive energy.

Selective partial hydrogenation of alkynes to (Z)-alkenes with ionic liquid-doped nickel nanocatalysts at near ambient conditions

A selective hydrogenation method for forming (Z)-alkenes from alkynes has been developed using a catalyst system of cheap Ni-NPs in a nitrile functionalised imidazolium based ionic liquid (IL) operating under very mild reaction conditions of 30–50 °C and 1–4 bar H₂ pressure.

Enzymatic Biosynthesis of Novel Resveratrol Glucoside and Glycoside Derivatives

A UDP glucosyltransferase from Bacillus licheniformis was overexpressed, purified, and incubated with nucleotide diphosphate (NDP) d- and l-sugars to produce glucose, galactose, 2-deoxyglucose, viosamine, rhamnose, and fucose sugar-conjugated resveratrol glycosides. Significantly higher (90%) bioconversion of resveratrol was achieved with α-d-glucose as the sugar donor to produce four different glucosides of resveratrol: resveratrol 3-O-β-d-glucoside, resveratrol 4'-O-β-d-glucoside, resveratrol 3,5-O-β-d-diglucoside, and resveratrol 3,5,4'-O-β-d-triglucoside. The conversion rates and numbers of products formed were found to vary with the other NDP sugar donors. Resveratrol 3-O-β-d-2-deoxyglucoside and resveratrol 3,5-O-β-d-di-2-deoxyglucoside were found to be produced using TDP-2-deoxyglucose as a donor; however, the monoglycosides resveratrol 4'-O-β-d-galactoside, resveratrol 4'-O-β-d-viosaminoside, resveratrol 3-O-β-l-rhamnoside, and resveratrol 3-O-β-l-fucoside were produced from the respective sugar donors. Altogether, 10 diverse glycoside derivatives of the medically important resveratrol were generated, demonstrating the capacity of YjiC to produce structurally diverse resveratrol glycosides.

Role of adenosine receptors in resveratrol-induced intraocular pressure lowering in rats with steroid-induced ocular hypertension

BACKGROUND

Steroid-induced ocular hypertension is currently treated in the same way as primary open-angle glaucoma. However, the treatment is often suboptimal and is associated with adverse effects. We evaluated the oculohypotensive effects of topical trans-resveratrol in rats with steroid-induced ocular hypertension and involvement of adenosine receptors (AR) in intraocular pressure (IOP) lowering effect of trans-resveratrol.

METHODS

The oculohypotensive effect of unilateral single-drop application of various concentrations of trans-resveratrol was first studied in oculonormotensive rats. Concentration with maximum effect was similarly studied in rats with steroid-induced ocular hypertension. Involvement of AR was studied by observing the alterations of IOP in response to trans-resveratrol after pretreating animals with AR subtype-specific antagonists. Additionally, we used computational methods, including 3D modelling, 3D structure generation and protein-ligand interaction, to determine the AR-trans-resveratrol interaction.

RESULTS

All concentrations of trans-resveratrol produced significant IOP reduction in normotensive rat eyes. Maximum mean IOP reduction of 15.1% was achieved with trans-resveratrol 0.2%. In oculohypertensive rats, trans-resveratrol 0.2% produced peak IOP reduction of 25.2%. Pretreatment with A₁ antagonist abolished the oculohypotensive effect of trans-resveratrol. Pretreatment with A₃ and A₂A AR antagonists produced significant IOP reduction in both treated and control eyes, which was further augmented by trans-resveratrol application in treated eyes. Computational studies showed that trans-resveratrol has highest affinity for A₂B and A₁, followed by A2A and A₃ AR.

CONCLUSION

Topically applied trans-resveratrol reduces IOP in rats with steroid-induced ocular hypertension. Trans-resveratrol-induced oculohypotension involves its agonistic activity at the A₁ AR.

Resveratrol in prostate diseases - a short review

Introduction

Resveratrol is a plant–derived polyphenol suggested to have many beneficial health effects, including antioxidant, anti–inflammatory, anti–proliferative, proapoptotic, and anti–angiogenic. It is even specu- lated that uptake of resveratrol by red wine consumption could be behind the so–called French paradox the lower incidence of cardiovascular diseases in the French population. These properties, together with good absorption and tolerance, would make it an attractive agent in prostatic diseases, especially in cancer prevention and treatment.

Material and methods

MEDLINE search (keywords “prostate res- veratrol”) resulted in 39 research papers published since 2007. It has been shown that resveratol down–regulate androgen receptor expression, inhibit proliferation, and promote apop- tosis in prostate cancer cell lines and enhance their sensitivity to ionizing radiation. Several studies on animal prostate cancer development also suggest that resveratrol is able do delay or prevent carcino- genesis in prostate. Despite these promising results, there is no proof of any therapeutic properties of resveratrol in prostate diseases from human clinical trials nor any information about ongoing trials in this field.

Conclusions

Resveratrol is produced and sold as a nutritional supplement, there is not enough clinical evidence to justify a recommendation for the administration of resveratrol in humans at present.

Resveratrol and related stilbenes: their anti-aging and anti-angiogenic properties

Dietary stilbenes comprise a class of natural compounds that display significant biological activities of medicinal interest. Among them, their antioxidant, anti-aging and anti-angiogenesic properties are well established and subjects of numerous research endeavors. This mini-review aspires to account and present the literature reports published on research concerning various natural and synthetic stilbenes, such as trans-resveratrol. Special focus was given to most recent research findings, while the mechanisms underlying their anti-aging and anti-angiogenic effects as well as the respective signaling pathways involved were also presented and discussed.