Development of dietary small molecules as multi-targeting treatment strategies for Alzheimer's disease

Cognitive dysfunction can occur both in normal aging and age-related neurological disorders, such as mild cognitive impairment and Alzheimer's disease (AD). These disorders have few treatment options due to side effects and limited efficacy. New approaches to slow cognitive decline are urgently needed. Dietary interventions (nutraceuticals) have received considerable attention because they exhibit strong neuroprotective properties and may help prevent or minimize AD symptoms. Biological aging is driven by a series of interrelated mechanisms, including oxidative stress, neuroinflammation, neuronal apoptosis, and autophagy, which function through various signaling pathways. Recent clinical and preclinical studies have shown that dietary small molecules derived from natural sources, including flavonoids, carotenoids, and polyphenolic acids, can modulate oxidative damage, cognitive impairments, mitochondrial dysfunction, neuroinflammation, neuronal apoptosis, autophagy dysregulation, and gut microbiota dysbiosis. This paper reviews research on different dietary small molecules and their bioactive constituents in the treatment of AD. Additionally, the chemical structure, effective dose, and specific molecular mechanisms of action are comprehensively explored. This paper also discusses the advantages of using nanotechnology-based drug delivery, which significantly enhances oral bioavailability, safety, and therapeutic effect, and lowers the risk of adverse effects. These agents have considerable potential as novel and safe therapeutic agents that can prevent and combat age-related AD.

Dysfunction of the Brown Adipose Organ in HFD-Obese Rats and Effect of Tart Cherry Supplementation

Obesity has a great impact on adipose tissue biology, based on its function as a master regulator of energy balance. Brown adipose tissue (BAT) undergoes remodeling, and its activity declines in obese subjects due to a whitening process. The anti-obesity properties of fruit extracts have been reported. The effects of tart cherry against oxidative stress, inflammation, and the whitening process in the BAT of obese rats were investigated. Intrascapular BAT (iBAT) alterations and effects of Prunus cerasus L. were debated in rats fed for 17 weeks with a high-fat diet (DIO), in DIO supplemented with seed powder (DS), and with seed powder plus the juice (DJS) of tart cherry compared to CHOW rats fed with a normo-caloric diet. iBAT histologic observations revealed a whitening process in DIO rats that was reduced in the DS and DJS groups. A modulation of uncoupling protein-1 (UCP-1) protein and gene expression specifically were detected in the obese phenotype. An upregulation of UCP-1 and related thermogenic genes after tart cherry intake was detected compared to the DIO group. Metabolic adjustment, endoplasmic reticulum stress, protein carbonylation, and the inflammatory microenvironment in the iBAT were reported in DIO rats. The analysis demonstrated an iBAT modulation that tart cherry promoted. In addition to our previous results, these data confirm the protective impact of tart cherry consumption on obesity.

Tumor microenvironment remodeling in oral cancer: Application of plant derived-natural products and nanomaterials

Oral cancers consist of squamous cell carcinoma (SCC) and other malignancies in the mouth with varying degrees of invasion and differentiation. For many years, different modalities such as surgery, radiation therapy, and classical chemotherapy drugs have been used to control the growth of oral tumors. Nowadays, studies have confirmed the remarkable effects of the tumor microenvironment (TME) on the development, invasion, and therapeutic resistance of tumors like oral cancers. Therefore, several studies have been conducted to modulate the TME in various types of tumors in favor of cancer suppression. Natural products are intriguing agents for targeting cancers and TME. Flavonoids, non-flavonoid herbal-derived molecules, and other natural products have shown promising effects on cancers and TME. These agents, such as curcumin, resveratrol, melatonin, quercetin and naringinin have demonstrated potency in suppressing oral cancers. In this paper, we will review and discuss about the potential efficacy of natural adjuvants on oral cancer cells. Furthermore, we will review the possible therapeutic effects of these agents on the TME and oral cancer cells. Moreover, the potential of nanoparticles-loaded natural products for targeting oral cancers and TME will be reviewed. The potentials, gaps, and future perspectives for targeting TME by nanoparticles-loaded natural products will also be discussed.

Co-administration of curcumin with other phytochemicals improves anticancer activity by regulating multiple molecular targets

Natural plant phytochemicals are effective against different types of diseases, including cancer. Curcumin, a powerful herbal polyphenol, exerts inhibitory effects on cancer cell proliferation, angiogenesis, invasion, and metastasis through interaction with different molecular targets. However, the clinical use of curcumin is limited due to poor solubility in water and metabolism in the liver and intestine. The synergistic effects of curcumin with some phytochemicals such as resveratrol, quercetin, epigallocatechin-3-gallate, and piperine can improve its clinical efficacy in cancer treatment. The present review specifically focuses on anticancer mechanisms related to the co-administration of curcumin with other phytochemicals, including resveratrol, quercetin, epigallocatechin-3-gallate, and piperine. According to the molecular evidence, the phytochemical combinations exert synergistic effects on suppressing cell proliferation, reducing cellular invasion, and inducing apoptosis and cell cycle arrest. This review also emphasizes the significance of the co-delivery vehicles-based nanoparticles of such bioactive phytochemicals that could improve their bioavailability and reduce their systemic dose. Further high-quality studies are needed to firmly establish the clinical efficacy of the phytochemical combinations.

[Anthocyanins as functional food components]

Среди встречающихся в природе пигментов антоцианы являются, пожалуй, одной из наиболее изученных групп. Начиная с первых исследований о физико-химических свойствах антоцианов, проведенных еще в XVII в. британским естествоиспытателем Р. Бойлем, наука об этих уникальных соединениях сделала огромный шаг вперед. На сегодняшний день достаточно хорошо исследованы структура и функции антоцианов в растительных клетках, а путь их биосинтеза – один из самых полно охарактеризованных путей биосинтеза вторичных метаболитов как на биохимическом, так и на генетическом уровне. Наряду с этими фундаментальными достижениями, мы начинаем осознавать потенциал антоцианов как соединений промышленного значения, как пигментов самих по себе, а также в качестве компонентов функционального питания, способствующих предупреждению и снижению риска развития хронических заболеваний. Долгое время биологическая активность антоцианов была недооценена, в частности, из-за данных об их низкой биодоступности. Однако в ходе исследований было показано, что в организме человека и животных эти соединения активно метаболизируются и биодоступность, оцененная с учетом их метаболитов, превышала 12 %. Экспериментально подтверждено, что антоцианы обладают антиоксидантными, противовоспалительными, гипогликемическими, антимутагенными, антидиабетическими, противораковыми, нейропротекторными свойствами, а также полезны для здоровья глаз. Однако проведенные исследования не всегда могут объяснить молекулярные механизмы действия антоцианов в организме человека. По некоторым данным, наблюдаемые эффекты объясняются действием не антоцианов, а их метаболитов, которые, благодаря своей повышенной биодоступности, могут быть более биологически активными, чем исходные соединения. Высказывается также предположение о положительном эффекте на здоровье человека всего комплекса полифенольных соединений, поступающего в организм в составе растительной пищи. В представленном обзоре суммированы результаты основных направлений исследований антоцианов в качестве компонентов функционального питания. Отдельное внимание уделено результатам генетических исследований синтеза пигментов, данные которых приобретают особую важность в связи с актуализацией селекционных программ, направленных на повышение содержания антоцианов у культурных растений. Ключевые слова: растения; пигменты; вторичные метаболиты; флавоноиды; антоцианы; регуляторные гены; структурные гены; антиоксиданты; биологическая активность.

Evaluation of the target-specific therapeutic potential of herbal compounds for the treatment of cancer

Cancer is among one of the most fatal diseases leading to millions of death around the globe. Chemotherapy is the most popular conventional approach for the treatment of cancer. However, this is usually associated with various side effects and puts the patients under extreme physical and mental stress. Besides, there are increasing concerns about drug resistance. Thus, to surmount these limitations, there is a need to explore some alternative treatments. Studies related to plant-derived compounds are crucial in the search for safer and more efficient treatments. Plants and their associated secondary metabolites have been a revolutionary approach in the field of cancer treatment, as they give answers to almost all the constraints faced by synthetic drugs. Various plants and associated secondary metabolites display a great prospective as cytotoxic anticancer agents due to their specific interference with validated drug targets, such as inhibitors of mitosis, topoisomerase I and II inhibitor, DNA interactive agent, protein kinase inhibitors, inhibitors of DNA synthesis. In this review, the therapeutic potential of various natural compounds and their derivatives are presented based on their molecular targets. These herbal compounds and their derivatives could provide a rich resource for novel anticancer drug development.

Critical discovery and synthesis of novel antibacterial and resistance-modifying agents inspired by plant phytochemical defense mechanisms

Antimicrobial resistance is at increasing risk worldwide since it is threatening the ability to control common infectious diseases, resulting in prolonged illness, disability, and death. Herein, we inspired by the effective plant phytochemical mechanisms evolved to overcome microbial pathogenesis and evolved resistance. Cuminaldehyde is previously reported as the main antibacterial component in Calligonum comosum essential oil. The toxicity of cuminaldehyde limits its medical application for human use. On the other hand, compared to cuminaldehyde, the plant total extract showed similar antibacterial activities, while maintained lower toxicity, although it contains 22 times less cuminaldehyde. Thus, we assumed that other components in the plant extracts specifically affect bacteria but not mammalian cells. Bioassay-guided fractionations combined with comparative metabolomics analysis of different plant extracts were employed. The results revealed the presence of bacterial species-specific phytochemicals. Cinnamyl linoleate and linoleic acid enhanced the antibacterial activities of cuminaldehyde and ampicillin against S. aureus including MRSA, while decanal and cinnamyl linoleate enhanced the activities against E. coli. Computational modeling and enzyme inhibition assays indicated that cinnamyl linoleate selectively bind to bacterial ribosomal RNA methyltransferase, an important enzyme involved in the virulence and resistance of multidrug resistant bacteria. The results obtained can be employed for the future preparation of pharmaceutical formula containing cinnamyl linoleate in order to overcome evolved multidrug resistance behaviors by microbes.

Delineating effect of corn microRNAs and matrix, ingested as whole food, on gut microbiota in a rodent model

Dietary microRNAs (miRNAs) are thought to regulate a wide range of biological processes, including the gut microbiota. However, it is difficult to separate specific effect(s) of miRNA from that of the food matrix. This study aims to elucidate the specific effect(s) of dietary corn miRNAs, ingested as a whole food, on the gut microbiota. We developed an autoclave procedure to remove 98% of miRNA from corn. A mouse feeding study was conducted comparing autoclaved corn to nonautoclaved corn and purified corn miRNA. Compared to nonspecific nucleotides and corn devoid of miRNAs, feeding purified corn miRNAs or corn to C57BL/6 mice via gavage or diet supplementation for two weeks lead to a decrease in total bacteria in the cecum. The effect appeared to be due to changes in Firmicutes. Additionally, corn matrix minus miRNA and processing also affected gut bacteria. In silico analysis identified corn miRNAs that aligned to Firmicutes genome sequences lending further support to the interaction between corn miRNAs and this bacterium. These data support interactions between plant food miRNA, as well as matrix, and the gut microbiota exist but complex. However, it provides additional support for mechanism by which bioactive dietary components interact with the gut microbiota.

Lysosomes, Autophagy, and Hormesis in Cell Physiology, Pathology, and Age-Related Disease

Autophagy has been strongly linked with hormesis, however, it is only relatively recently that the mechanistic basis underlying this association has begun to emerge. Lysosomal autophagy is a group of processes that degrade proteins, protein aggregates, membranes, organelles, segregated regions of cytoplasm, and even parts of the nucleus in eukaryotic cells. These degradative processes are evolutionarily very ancient and provide a survival capability for cells that are stressed or injured. Autophagy and autophagic dysfunction have been linked with many aspects of cell physiology and pathology in disease processes; and there is now intense interest in identifying various therapeutic strategies involving its regulation. The main regulatory pathway for augmented autophagy is the mechanistic target of rapamycin (mTOR) cell signaling, although other pathways can be involved, such as 5'-adenosine monophosphate-activated protein kinase. Mechanistic target of rapamycin is a key player in the many highly interconnected intracellular signaling pathways and is responsible for the control of cell growth among other processes. Inhibition of mTOR (specifically dephosphorylation of mTOR complex 1) triggers augmented autophagy and the search is on the find inhibitors that can induce hormetic responses that may be suitable for treating many diseases, including many cancers, type 2 diabetes, and age-related neurodegenerative conditions.

Essential Oil Phytocomplex Activity, a Review with a Focus on Multivariate Analysis for a Network Pharmacology-Informed Phytogenomic Approach

Thanks to omic disciplines and a systems biology approach, the study of essential oils and phytocomplexes has been lately rolling on a faster track. While metabolomic fingerprinting can provide an effective strategy to characterize essential oil contents, network pharmacology is revealing itself as an adequate, holistic platform to study the collective effects of herbal products and their multi-component and multi-target mediated mechanisms. Multivariate analysis can be applied to analyze the effects of essential oils, possibly overcoming the reductionist limits of bioactivity-guided fractionation and purification of single components. Thanks to the fast evolution of bioinformatics and database availability, disease-target networks relevant to a growing number of phytocomplexes are being developed. With the same potential actionability of pharmacogenomic data, phytogenomics could be performed based on relevant disease-target networks to inform and personalize phytocomplex therapeutic application.

Synergy and antagonism in natural product extracts: when 1 + 1 does not equal 2

Covering: 2000 to 2019 According to a 2012 survey from the Centers for Disease Control and Prevention, approximately 18% of the U.S. population uses natural products (including plant-based or botanical preparations) for treatment or prevention of disease. The use of plant-based medicines is even more prevalent in developing countries, where for many they constitute the primary health care modality. Proponents of the medicinal use of natural product mixtures often claim that they are more effective than purified compounds due to beneficial "synergistic" interactions. A less-discussed phenomenon, antagonism, in which effects of active constituents are masked by other compounds in a complex mixture, also occurs in natural product mixtures. Synergy and antagonism are notoriously difficult to study in a rigorous fashion, particularly given that natural products chemistry research methodology is typically devoted to reducing complexity and identifying single active constituents for drug development. This report represents a critical review with commentary about the current state of the scientific literature as it relates to studying combination effects (including both synergy and antagonism) in natural product extracts. We provide particular emphasis on analytical and Big Data approaches for identifying synergistic or antagonistic combinations and elucidating the mechanisms that underlie their interactions. Specific case studies of botanicals in which synergistic interactions have been documented are also discussed. The topic of synergy is important given that consumer use of botanical natural products and associated safety concerns continue to garner attention by the public and the media. Guidance by the natural products community is needed to provide strategies for effective evaluation of safety and toxicity of botanical mixtures and to drive discovery in botanical natural product research.

Antioxidant and Hepatoprotective Effects of Croton hypoleucus Extract in an Induced-Necrosis Model in Rats

The aim of this study was to evaluate the antioxidant and hepatoprotective activity of Croton hypoleucus (EC). The present work reports the first pharmacological, toxicological, and antioxidant studies of EC extract on liver injury. Liver necrosis was induced by thioacetamide (TAA). Five groups were established: Croton Extract (EC), thioacetamide (TAA), Croton extract with thioacetamide (EC + TAA), vitamin E with thioacetamide (VE + TAA) and the positive control and vehicle (CT). For EC and EC + TAA, Wistar rats (n = 8) were intragastrically pre-administered for 4 days with EC (300 mg/kg.day) and on the last day, EC + TAA received a single dose of TAA (400 mg/kg). At 24 h after damage induction, animals were sacrificed. In vitro activity and gene expression of superoxide dismutase (SOD), catalase (Cat), and Nrf2 nuclear factor were measured. The results show that EC has medium antioxidant properties, with an IC₅₀ of 0.63 mg/mL and a ferric-reducing power of 279.8 µM/mg. Additionally, EC reduced hepatic damage markers at 24 h after TAA intoxication; also, it increased SOD and Cat gene expression against TAA by controlling antioxidant defense levels. Our findings demonstrated the hepatoprotective effect of EC by reducing hepatic damage markers and controlling antioxidant defense levels. Further studies are necessary to identify the mechanism of this protection.

Aonla phytochemicals: extraction, identification and quantification

Methanolic, ethanolic and ethyl acetate extracts of five aonla varieties were analyzed for phytochemical characterization using RP-HPLC. Five compounds viz. ascorbic acid, gallic acid, ellagic acid, ethyl gallate and quercetin were identified in aonla extracts by RP-HPLC at 270 nm. Significant variations were observed in amount of identified phytochemical among the varieties. The highest level of phytochemical was observed in methanolic extract of variety Desi followed by varieties Kanchan, NA-7, Banarasi and Chakaiya. Among the solvent, methanol extracted the maximum phytochemicals while yield was least in ethyl acetate extract of aonla varieties. Gallic acid and ellagic acid were the most abundant phenolic compounds in extracts of aonla varieties. Ellagic acid (349.51 mg/100 g) and gallic acid (233.49 mg/100 g) were found maximum in methanolic extract of Desi variety. Results of the present study suggested that aonla is a good source of phenolic and flavonoid compounds.

Development of botanicals to combat antibiotic resistance

The discovery of antibiotics in the previous century lead to reduction in mortality and morbidity due to infectious diseases but their inappropriate and irrational use has resulted in emergence of resistant microbial populations. Alteration of target sites, active efflux of drugs and enzymatic degradations are the strategies employed by the pathogenic bacteria to develop intrinsic resistance to antibiotics. This has led to an increased interest in medicinal plants since 25-50% of current pharmaceuticals are plant derived. Crude extracts of medicinal plants could serve as an alternate source of resistance modifying agents owing to the wide variety of secondary metabolites. These metabolites (alkaloids, tannins, polyphenols etc.) could act as potentials for antimicrobials and resistance modifiers. Plant extracts have the ability to bind to protein domains leading to modification or inhibition protein-protein interactions. This enables the herbals to also present themselves as effective modulators of host related cellular processes viz immune response, mitosis, apoptosis and signal transduction. Thus they may exert their activity not only by killing the microorganism but by affecting key events in the pathogenic process, thereby, the bacteria, fungi and viruses may have a reduced ability to develop resistance to botanicals. The article is meant to stimulate research wherein the cidal activity of the extract is not the only parameter considered but other mechanism of action by which plants can combat drug resistant microbes are investigated. The present article emphasizes on mechanisms involved in countering multi drug resistance.

Looking to nature for a new concept in antimicrobial treatments: isoflavonoids from Cytisus striatus as antibiotic adjuvants against MRSA

The spread of multidrug-resistant Staphylococcus aureus strains, including methicillin-resistant S. aureus (MRSA), has shortened the useful life of anti-staphylococcal drugs enormously. Two approaches can be followed to address this problem: screening various sources for new leads for antibiotics or finding ways to disable the resistance mechanisms to existing antibiotics. Plants are resistant to most microorganisms, but despite extensive efforts to identify metabolites that are responsible for this resistance, no substantial progress has been made. Plants possibly use multiple strategies to deal with microorganisms that evolved over time. For this reason, we searched for plants that could potentiate the effects of known antibiotics. From 29 plant species tested, Cytisus striatus clearly showed such an activity and an NMR-based metabolomics study allowed the identification of compounds from the plant extracts that could act as antibiotic adjuvants. Isoflavonoids were found to potentiate the effect of ciprofloxacin and erythromycin against MRSA strains. For the structure-activity relationship (SAR), 22 isoflavonoids were assessed as antibiotic adjuvants. This study reveals a clear synergy between isoflavonoids and the tested antibiotics, showing their great potential for applications in the clinical therapy of infections with antibiotic-resistant microorganisms such as MRSA.

Potentiation of the bioavailability of blueberry phenolic compounds by co-ingested grape phenolic compounds in mice, revealed by targeted metabolomic profiling in plasma and feces

The low bioavailability of dietary phenolic compounds, resulting from poor absorption and high rates of metabolism and excretion, is a concern as it can limit their potential beneficial effects on health. Targeted metabolomic profiling in plasma and feces of mice supplemented for 15 days with a blueberry extract, a grape extract or their combination revealed significantly increased plasma concentrations (3-5 fold) of blueberry phenolic metabolites in the presence of a co-ingested grape extract, associated with an equivalent decrease in their appearance in feces. Additionally, the repeated daily administration of the blueberry-grape combination significantly increased plasma phenolic concentrations (2-3-fold) compared to animals receiving only a single acute dose, with no such increase being observed with individual extracts. These findings highlight a positive interaction between blueberry and grape constituents, in which the grape extract enhanced the absorption of blueberry phenolic compounds. This study provides for the first time in vivo evidence of such an interaction occurring between co-ingested phenolic compounds from fruit extracts leading to their improved bioavailability.

Review on mechanisms and interactions in concomitant use of herbs and warfarin therapy

The effectiveness of warfarin, an oral anticoagulant originally derived from a plant, is strongly affected by patient's characteristics such as the age, presence of comorbidities, and concomitant use of another drug. Warfarin has the potential to interact with many drugs, medicinal plants, and food, which increases the risk of adverse events. A critical analysis of scientific literature was conducted to assess the interferences of medicinal plants with blood haemostasis and then with warfarin anticoagulation. We found 58 different plants that may alter the blood haemostasis and anticoagulation with warfarin. The herbs that showed the greatest potential to interact with warfarin include garlic, ginger, ginkgo, St. John's wort, and ginseng, i.e. plants normally consumed as food and also used for therapeutic purposes. The interactions between drugs and herbs are varied because of the complex chemical matrix of plants. Mainly coumarins, quinones, xanthones, terpenes, lignans, and vitamin K showed significant influence on warfarin treatment. In general, these plants can potentiate the effect of warfarin by stimulating anticoagulation in multiple ways, and the clinical outcome associated with this interaction is the increase of bleeding risk. Moreover, potential interactions between herbal products and drugs are a safety concern, especially for drugs with a narrow therapeutic index or for patients receiving drug treatment for chronic diseases, and both of these apply to warfarin pharmacotherapy. Therefore, this review article summarises the data on the influence of medicinal plants on warfarin treatment and analyses this information in view of the interaction targets. The relevant plants were categorised according to their target, and their effects are discussed in order to organise the isolated information and to highlight the need of further discussion and new studies on the safety of herbal medicines and warfarin.

Dietary flavonoids and nitrate: effects on nitric oxide and vascular function

Emerging evidence highlights dietary flavonoids and nitrate as candidates that may explain at least part of the cardioprotective effect of a fruit and vegetable diet. Nitric oxide plays a pivotal role in cardiovascular health. Components of a fruit and vegetable diet that are cardioprotective, in part through effects on nitric oxide status, could substantially reduce the cardiovascular risk profile of the general population with increased intake of such a diet. Epidemiological evidence suggests that dietary flavonoids and nitrate have a cardioprotective effect. Clinical trials with flavonoid- and nitrate-rich foods have shown benefits on measures of vascular health. While the molecular mechanisms by which flavonoids and nitrate are cardioprotective are not completely understood, recent evidence suggests both nonspecific and specific effects through nitric oxide pathways. This review presents an overview of nitric oxide and its key role in cardiovascular health and discusses the possible vascular benefits of flavonoids and nitrate, individually and in combination, through effects on nitric oxide status.

Alteration of anti-inflammatory activity of Harpagophytum procumbens (devil's claw) extract after external metabolic activation with S9 mix

OBJECTIVES

Extracts of the tubers of Harpagophytum procumbens (devil's claw, DC) inhibit different proinflammatory mediators important in the pathophysiology of osteoarthritis. Many plant-derived preparations interfere with cytochrome P450 liver enzymes, which influence their different biological activities. Therefore, the present study was designed to investigate the influence of an external metabolic activation of a DC extract on the cytotoxicity and the release of proinflammatory cytokines.

METHODS

A screening experiment with a panel of 12 inflammatory cytokines identified three as suitable for the study: tumour necrosis factor-α (TNF-α), interleukin (IL) IL-6 and IL-8. They were determined using enzyme-linked immunosorbent assays in lipopolysaccharide (LPS)-stimulated monocytic THP-1 cells, which were treated with rat liver S9 mix metabolically activated DC extract (DCm). For the cytotoxity experiments, a WST-1 assay was used.

KEY FINDINGS

DC dose-dependently suppressed the release of TNF-α, IL-6 and IL-8 in LPS-stimulated monocytic THP-1 cells at non-cytotoxic concentrations (50-250 μg/ml). The metabolic activation of the DC extract by S9 mix did not alternate its cytotoxicity and did not diminish its inhibitory effect. This effect was improved in the case of TNF-α inhibition as reflected by their EC50 values of 116 ± 8.2 μg/ml and 49 ± 3.5 μg/ml for DC and DCm (P < 0.01).

CONCLUSIONS

Cytokines inhibitory activity of DC was not affected after its external metabolic activation. However, the amount of harpagoside and caffeic acid derivates was decreased. Other components of the extract might have contributed to its anti-inflammatory effect.

Evaluation of the best method to assess antibiotic potentiation by phytochemicals against Staphylococcus aureus

The increasing occurrence of bacterial resistance to antibiotics has now reached a critical level. Finding antibiotic coadjuvants capable to inhibit the bacterial resistance mechanisms would be a valuable mid-term solution, until new classes of antibiotics are discovered. Selected plant alkaloids were combined with 5 antibiotics against 10 Staphylococcus aureus strains, including strains expressing distinct efflux pumps and methicillin-resistant S. aureus strains. The efficacy of each combination was assessed using the microdilution checkerboard, time-kill, Etest, and disc diffusion methods. The cytotoxicity of the alkaloids was evaluated in a mouse fibroblast cell line. Potentiation was obtained in 6% of all 190 combinations, especially with the combination of: ciprofloxacin with reserpine (RES), pyrrolidine (PYR), and quinine (QUIN); tetracycline with RES; and erythromycin with PYR. The highest cytotoxicity values were found for QUIN (half maximal inhibitory concentration [IC50] = 25 ± 2.2 mg/L) and theophylline (IC50 = 100 ± 4.7 mg/L).

Combination of low dose of genistein and daidzein has synergistic preventive effects on isogenic human prostate cancer cells when compared with individual soy isoflavone

The reduced incidence of prostate cancer (PCa) in Asia countries has been attributed to high soy diets, and major soy isoflavones, in particular daidzein and genistein, are thought to be the source of the beneficial and anti-cancer effects of soy foods. However, attention has been drawn to the safety of using high levels of soy isoflavones in humans, which is especially the concern for consumers taking regular soy isoflavone dietary supplements. The main objective of this study is thus to identify a soy isoflavone combination with lower levels of daidzein and genistein to be a more efficacious and safer chemo-preventive agent for PCa. The anticancer effects of daidzein and genistein, and their combinations on early-stage androgen-dependent PCa cells (LNCaP) and bone metastatic LNCaP-derivative PCa cells (C4-2B) were compared. Cells were treated with varying concentrations of daidzein, genistein (25-200 μM) or their combinations (25 or 50 μM) and cell proliferation, apoptosis, cell cycles and cellular uptakes of the isoflavones were measured after 48 h. Daidzein and genistein showed a synergistic effect on inhibiting cell proliferation and inducing apoptosis of both PCa cells. Twenty-five μM daidzein/50 μM genistein and 50 μM daidzein/50 μM genistein significantly increased the apoptotic effects on C4-2B cells although they did not show any effect when used individually. Except 50 μM daidzein/50 μM genistein, all other combinations had no impacts on cell cycles. For treatment with soy isoflavone combination, genistein was always better taken up than daidzein by both LNCaP and C4-2B cells.

Apoptotic effects of cooked and in vitro digested soy on human prostate cancer cells

Previous laboratory and animal studies reported that soy isoflavones were major bioactive compounds in soy to exert chemoprotection of prostate cancer. However, these studies cannot reflect the realistic effects that soy may induce through diets, and little is known about the bioavailability of isoflavones from whole soy food and their bioactivities after cooking and digestion. In this study, cooking and in vitro digestion were used to prepare soy extracts and the effects of cooking and digestion on the isoflavone contents and bioactivities of the whole soy extracts were examined. The cooking procedure generally increased the amount of daidzin, genistin and daidzein, but decreased that of genistein. Digestion process significantly lowered contents of daidzin and genistin in 60min cooked sample, while increased the contents of daidzin and daidzein and decreased the content of genistein in the uncooked sample. Antioxidant activities of soy extracts increased after cooking and in vitro digestion, while no consistent increase of the four soy isoflavones was determined. The apoptotic effects of soy extracts on both LNCaP and C4-2B cells were generally in a dose-dependent manner. Compared to purified single isoflavones, cooked and digested soy were more effective on induction of prostate cancer cell apoptosis, which indicated synergistic interactions between various bioactive compounds in the whole soy.

Investigation on the protective effects of cranberry against the DNA damage induced by benzo[a]pyrene

There are few reports that demonstrate the antigenotoxic potential of cranberries. Although the types of berry fruits consumed worldwide are many, this paper focuses on cranberries that are commonly consumed in Mexico (Vaccinium macrocarpon species). The purpose of the present study is to determine whether cranberry ethanolic extract (CEE) can prevent the DNA damage produced by benzo[a]pyrene (B[a]P) using an in vivo mouse peripheral blood micronucleus assay. The experimental groups were organized as follows: a negative control group (without treatment), a positive group treated with B[a]P (200 mg/kg), a group administered with 800 mg/kg of CEE, and three groups treated with B[a]P and CEE (200, 400, and 800 mg/kg) respectively. The CEE and benzo[a]pyrene were administered orally for a week, on a daily basis. During this period the body weight, the feed intake, and the determination of antigenotoxic potential were quantified. At the end of this period, we continued with the same determinations for one week more (recovery period) but anymore administration of the substances. The animals treated with B[a]P showed a weight increase after the first week of administration. The same phenomenon was observed in the lots combined with B[a]P and CEE (low and medium doses). The dose of 800 mg/kg of CEE showed similar values to the control group at the end of the treatment period. In the second part of the assay, when the substances were not administered, these experimental groups regained their normal weight. The dose of CEE (800 mg/kg) was not genotoxic nor cytotoxic. On the contrary, the B[a]P increases the frequency of micronucleated normochromatic erythrocytes (MNNE) and reduces the rate of polychromatic erythrocytes (PE) at the end of the treatment period. With respect to the combined lots, a significant decrease in the MN rate was observed from the sixth to the eighth day of treatment with the two high doses applied; the highest protection (60%) was obtained with 800 mg/kg of CEE. The same dose showed an anticytotoxic effect which corresponded to an improvement of 62.5% in relation to the animals administered with the B[a]P. In the second period, all groups reached values that have been seen in the control group animals. Our results suggest that the inhibition of clastogenicity of the cranberry ethanolic extract against B[a]P is related to the antioxidant capacity of the combination of phytochemicals present in its chemical composition.

An update on the strategies in multicomponent activity monitoring within the phytopharmaceutical field

Background

To-date modern drug research has focused on the discovery and synthesis of single active substances. However, multicomponent preparations are gaining increasing importance in the phytopharmaceutical field by demonstrating beneficial properties with respect to efficacy and toxicity.

Discussion

In contrast to single drug combinations, a botanical multicomponent therapeutic possesses a complex repertoire of chemicals that belong to a variety of substance classes. This may explain the frequently observed pleiotropic bioactivity spectra of these compounds, which may also suggest that they possess novel therapeutic opportunities. Interestingly, considerable bioactivity properties are exhibited not only by remedies that contain high doses of phytochemicals with prominent pharmaceutical efficacy, but also preparations that lack a sole active principle component. Despite that each individual substance within these multicomponents has a low molar fraction, the therapeutic activity of these substances is established via a potentialization of their effects through combined and simultaneous attacks on multiple molecular targets. Although beneficial properties may emerge from such a broad range of perturbations on cellular machinery, validation and/or prediction of their activity profiles is accompanied with a variety of difficulties in generic risk-benefit assessments. Thus, it is recommended that a comprehensive strategy is implemented to cover the entirety of multicomponent-multitarget effects, so as to address the limitations of conventional approaches.

Summary

An integration of standard toxicological methods with selected pathway-focused bioassays and unbiased data acquisition strategies (such as gene expression analysis) would be advantageous in building an interaction network model to consider all of the effects, whether they were intended or adverse reactions.

Isoflavones-Enriched Soy Protein Prevents CCL(4)-Induced Hepatotoxicity in Rats

The burden of liver disease in Egypt is exceptionally high due to the highest prevalence of hepatitis C virus (HCV) resulting in rising rates of hepatocellular carcinoma (HCC). The aim of the current study was to determine the isoflavones in soy and to evaluate the protective role of soy against CCl₄-induced liver damage in rats. Four experimental groups were treated for 8 weeks and included the control group, soy-supplemented diet (20% w/w) group, the group treated orally with CCl₄ (100 mg/kg bw) twice a week, and the group fed soy-supplemented diet and treated with CCl₄. Blood and liver tissue samples were collected for biochemical analyses and histological examination. The results indicated that protein content was 45.8% and the total isoflavones recorded 167.3 mg/100 g soy. Treatment with CCl₄ resulted in a significant biochemical changes in serum liver tissue accompanied with severe oxidative stress and histological changes. Supplementation with soy succeeded to restore the elevation of liver enzymes activities and improved serum biochemical parameters. Moreover, soy supplementation improved the antioxidant enzymes, decreased lipid peroxidation, and improved the histological picture of the liver tissue. It could be concluded that soy-protein-enriched isoflavones may be a promising agent against liver diseases.

Antioxidant capacity interactions and a chemical/structural model of phenolic compounds found in strawberries

The interactive antioxidant capacity of phenolic compounds from specific foods has not been well explored. The antioxidant capacity of a whole fruit exceeds the sum of the antioxidant capacities of individual antioxidants within that fruit, suggesting synergism among compounds. The interactions of seven phenolic compounds (p-coumaric acid, cyanidin, catechin, quercetin-3-glucoside, kaempferol, pelargonidin and ellagic acid) at relative concentrations found in strawberries were tested using the oxygen radical absorbance capacity assay. Statistically significant synergism was found for three combinations of two phenolic compounds, and among five combinations of three phenolic compounds. Statistically significant antagonism was observed among two combinations of two phenolic compounds and among one combination of three compounds. A chemical/structural model that best explained the results included reduction potentials, relative concentration, and the presence or absence of catechol (o-dihydroxy benzene) groups. This work demonstrates unique interactions that occur in a complex environment within the framework of strawberries. The synergism discovered at food-based antioxidant ratios could be applied to food preservation.

The complex links between dietary phytochemicals and human health deciphered by metabolomics

A large variety of phytochemicals commonly consumed with the human diet, influence health and may contribute to the prevention of diseases. However, it is still difficult to make nutritional recommendations for these bioactive compounds. Current studies of phytochemicals are generally focused on specific compounds and their effects on a limited number of markers. New approaches are needed to take into account both the diversity of phytochemicals found in the diet and the complexity of their biological effects. Recent progress in high-throughput analytical technologies and in bioinformatics now allows the simultaneous analysis of the hundreds or more metabolites constituting the metabolome in urine or plasma. These analyses give complex metabolic fingerprints characteristic of a given phenotype. The exploitation of the wealth of information it contains, in randomized controlled trials and cohort studies, should lead to the discovery of new markers of intake for phytochemicals and new markers of effects. In this paper, we briefly review the current methods used to evaluate intake of phytochemicals and their effects on health. We then describe the applications of metabolomics in this field. Recent metabolomics studies illustrate the potential of such a global approach to explore the complex relationships linking phytochemical intake and metabolism and health.

Differential effects of whole soy extract and soy isoflavones on apoptosis in prostate cancer cells

Previous studies have suggested that soy isoflavones exert anticarcinogenic effects against prostate cancer. We propose that soy extracts, containing a mixture of soy isoflavones and other bioactive components, would be a more potent chemo-preventive agent than individual soy isoflavones. We compared the apoptotic effects of whole soy extracts and individual soy isoflavones, genistein and daidzein, on prostate cancer cells. The soy extract contained 50% w/w of total isoflavones with approximately 1:5.5:3.5 ratios of genistin, daidzin and glycitin, respectively. Benign prostate hyperplasia (BPH-1), LnCap and PC3 cells were treated with varying concentrations of soy extract, genistein or daidzein and analyzed for cell cycle alterations and induction of apoptosis. At equal concentrations (25 micromol/L), soy extract induced a significantly higher percentage of cells undergoing apoptosis than genistein or daidzein (P < 0.001). No significant changes in cell cycle arrest or apoptosis were observed in non-cancerous BPH-1 cells treated with soy extract, suggesting that the effects of soy extract may be tumor cell specific. On the contrary, both genistein and daidzein induced apoptosis in BPH-1 cells, suggesting that individual isoflavones may have cytotoxicity in non-cancerous cells. Soy extracts also increased Bax expression in PC3 cells, but no significant changes in nuclear factor kappaB (NF kappaB) activation were detected, suggesting that the induction of apoptosis was independent of the NF kappaB pathway. Food products that bear a combination of active compounds may be more efficacious and safer as chemo-preventive agents than individual compounds. This 'whole-food'-based approach is significant for the development of public health recommendations for prostate cancer prevention.

Modulation of inflammatory genes by natural dietary bioactive compounds

Several epidemiologic studies have shown that chronic inflammation predisposes individuals to various types of cancer. Many cancers arise from sites of infection, chronic irritation, and inflammation. Conversely, an oncogenic change induces an inflammatory microenvironment that promotes the development of tumors. Natural bioactive compounds in dietary plant products including fruits, vegetables, grains, legumes, tea, and wine are claimed to help prevent cancer, degenerative diseases, and chronic and acute inflammation. Modern methods in cell and molecular biology allow us to understand the interactions of different natural bioactive compounds with basic mechanisms of inflammatory response. The molecular pathways of this cancer-related inflammation are now unraveled. Natural bioactive compounds exert anti-inflammatory activity by modulating pro-inflammatory gene expressions have shown promising chemopreventive activity. This review summarizes current knowledge on natural bioactive compounds that act through the signaling pathways and modulate inflammatory gene expressions, thus providing evidence for these substances in cancer chemopreventive action.

Aged garlic extract stimulates p-glycoprotein and multidrug resistance associated protein 2 mediated effluxes

The growing concomitant consumption of drugs and herbal preparations such as garlic, and the numerous reports about the influence of herbal preparations on intestinal transport, led us to evaluate the influence of aged garlic extract on the transport function and electrophysiological parameters of the small intestinal mucosa. Aged garlic extract induced increase of the absolute value of the transepithelial potential difference and of the short-circuit current in both permeability models tested (rat jejunum, Caco-2 cell monolayers) without affecting transepithelial electrical resistance. It also caused a significant increase of the P-glycoprotein and multidrug resistance associated protein 2 mediated effluxes through rat jejunum of marker substrates Rhodamine 123 and 2,4-dinitrophenyl-S-glutathione, respectively. Rhodamine 123 efflux through the Caco-2 cell monolayers was not altered by aged garlic extract, whereas the efflux of 2,4-dinitrophenyl-S-glutathione increased significantly. So altered activity of the important transport proteins could significantly change the pharmacokinetic properties of conventional medicines taken concomitantly with aged garlic extract.

Isoflavones and the prevention of breast and prostate cancer: new perspectives opened by nutrigenomics

Epidemiological evidence together with preclinical data from animal and in vitro studies strongly support a correlation between soy isoflavone consumption and protection towards breast and prostate cancers. The biological processes modulated by isoflavones, and especially by genistein, have been extensively studied, yet without leading to a clear understanding of the cellular and molecular mechanisms of action involved. This review discusses the existing gaps in our knowledge and evaluates the potential of the new nutrigenomic approaches to improve the study of the molecular effects of isoflavones. Several issues need to be taken into account for the proper interpretation of the results already published for isoflavones. Too often knowledge on isoflavone bioavailability is not taken into account; supra-physiological doses are frequently used. Characterization of the individual variability as defined by the gut microflora composition and gene polymorphisms may also help to explain the discrepancies observed so far in the clinical studies. Finally, the complex inter-relations existing between tissues and cell types as well as cross-talks between metabolic and signalling pathways have been insufficiently considered. By appraising critically the abundant literature with these considerations in mind, the mechanisms of action that are the more likely to play a role in the preventive effects of isoflavones towards breast and prostate cancers are reviewed. Furthermore, the new perspectives opened by the use of genetic, transcriptomic, proteomic and metabolomic approaches are highlighted.

A natural history of botanical therapeutics

Plants have been used as a source of medicine throughout history and continue to serve as the basis for many pharmaceuticals used today. Although the modern pharmaceutical industry was born from botanical medicine, synthetic approaches to drug discovery have become standard. However, this modern approach has led to a decline in new drug development in recent years and a growing market for botanical therapeutics that are currently available as dietary supplements, drugs, or botanical drugs. Most botanical therapeutics are derived from medicinal plants that have been cultivated for increased yields of bioactive components. The phytochemical composition of many plants has changed over time, with domestication of agricultural crops resulting in the enhanced content of some bioactive compounds and diminished content of others. Plants continue to serve as a valuable source of therapeutic compounds because of their vast biosynthetic capacity. A primary advantage of botanicals is their complex composition consisting of collections of related compounds having multiple activities that interact for a greater total activity.

Evaluation of botanicals for improving human health

Botanical preparations have been used medicinally for thousands of years. Many commercially available botanical products are being marketed in the United States with little or no publicly available scientific validation of efficacy or consistency. For botanicals to be reliable for research purposes and consumer products, they must be standardized with sufficient quality controls to ensure consistent composition, safety, and potency. This includes uniform cultivation of source plants with controls to monitor for contamination from other species, pesticides, and environmental toxins. The active components of botanicals must be identified by activity-guided fractionation with the use of in vitro assays that require little test material followed by validation in vivo. Concentrations of active compounds within the botanicals can then be accurately measured to ensure the delivery of a dependable dose in the final product. The use of bioenhancing agents may be considered for compounds with poor bioavailability. Standardization of botanical therapeutics can only be achieved when the active compounds are identified and biological activity is confirmed, thus ensuring a consistent product.

Pharmacogenomics and nutrigenomics: synergies and differences

The success of the Human Genome Project and the spectacular development of broad genomics tools have catalyzed a new era in both medicine and nutrition. The terms pharmacogenomics and nutrigenomics are relatively new. Both have grown out of their genetic forbears as large-scale genomics technologies have been developed in the last decade. The aim of both disciplines is to individualize or personalize medicine and food and nutrition, and ultimately health, by tailoring the drug or the food to the individual genotype. This review article provides an overview of synergies and differences between these two potentially powerful science areas. Individual genetic variation is the common factor on which both pharmacogenomics and nutrigenomics are based. Each human is genetically (including epigenetics) unique and phenotypically distinct. One of the expectations of both technologies is that a wide range of gene variants and related single-nucleotide polymorphism will be identified as to their importance in health status, validated and incorporated into genotype based strategies for the optimization of health and the prevention of disease. Pharmacogenomics requires rigorous genomic testing that will be regulated and analyzed by professionals and acted on by medical practitioners. As further information is obtained on the importance of the interaction of food and the human genotype in disease prevention and health, pharmacogenomics can provide an opportunity driver for nutrigenomics. As we move from disease treatment to disease prevention, the two disciplines will become more closely aligned.

Chemical and biological characterisation of nutraceutical compounds of broccoli

People's diet offers a greater and more diverse group of plant bioactives than do drugs, and they often do not realise that many drugs are derived from the compounds originally discovered in plant foods. Numerous epidemiological studies indicate that Brassica vegetables in general, and broccoli in particular, protect humans against cancer since they are rich sources of glucosinolates as well as possessing a high content of flavonoids, vitamins and mineral nutrients. One unusual phytotherapeutic role of broccoli is for skin diseases--the juice of the leaves is used to treat warts. However, the main use of broccoli stems from its health-promoting properties. Some criteria have been proposed to evaluate the possibilities of developing new "functional foods" to reduce the risk of specific cancers; largely in broccoli, which is associated with cancer protection. Processing conditions, transport, domestic cooking, etc., affect the health-promoting properties of broccoli and these have been widely studied. This review makes an in-depth study of the chemical and biological characterization of the phytochemicals of broccoli and the effects on the bioactive composition of broccoli.