Role of Characteristic Components of Humulus lupulus in Promoting Human Health

Exploring the composition and potential uses of four hops varieties through different extraction techniques

Hydrophilic, lipophilic extracts and essential oil of four hops varieties from Slovenia were examined in this study. Lipophilic extracts were obtained by supercritical extraction (SFE), while for hydrophilic extracts ultrasound and microwave extraction were employed. Essential oils were isolated by the hydrodistillation process. The lipophilic composition of essential oils and lipophilic extracts was determined by GC-MS analysis. Monoterpenes and sesquiterpene hydrocarbons were the most abundant class of compounds in oils (62.27-79.65 %), with myrcene being the most abundant constituent. Limonene and trans-caryophyllene were two terpenes determined in all essential oils while only trans-caryophyllene was detected in SFE samples. Antioxidant, antimicrobial, and cytotoxic activity, determined by applying in vitro assays, was more influenced by extraction technique than by varieties. Molecular docking was carried out to gain insight into the potential cancer protein targets BCL-2 and MMP9, whereby humulene epoxide II displayed good binding configuration within the cavities of the two proteins.

Xanthohumol, a prenylated chalcone, regulates lipid metabolism by modulating the LXRα/RXR-ANGPTL3-LPL axis in hepatic cell lines and high-fat diet-fed zebrafish models

Angiopoietin-like 3 (ANGPTL3) acts as an inhibitor of lipoprotein lipase (LPL), impeding the breakdown of triglyceride-rich lipoproteins (TGRLs) in circulation. Targeting ANGPTL3 is considered a novel strategy for improving dyslipidemia and atherosclerotic cardiovascular diseases (ASCVD). Hops (Humulus lupulus L.) contain several bioactive prenylflavonoids, including xanthohumol (Xan), isoxanthohumol (Isoxan), 6-prenylnaringenin (6-PN), and 8-prenylnaringenin (8-PN), with the potential to manage lipid metabolism. The aim of this study was to investigate the lipid-lowering effects of Xan, the effective prenylated chalcone in attenuating ANGPTL3 transcriptional activity, both in vitro using hepatic cells and in vivo using zebrafish models, along with exploring the underlying mechanisms. Xan (10 and 20 μM) significantly reduced ANGPTL3 mRNA and protein expression in HepG2 and Huh7 cells, leading to a marked decrease in secreted ANGPTL3 proteins via hepatic cells. In animal studies, orally administered Xan significantly alleviated plasma triglyceride (TG) and cholesterol levels in zebrafish fed a high-fat diet. Furthermore, it reduced hepatic ANGPTL3 protein levels and increased LPL activity in zebrafish models, indicating its potential to modulate lipid profiles in circulation. Furthermore, molecular docking results predicted that Xan exhibits a higher binding affinity to interact with liver X receptor α (LXRα) and retinoic acid X receptor (RXR) than their respective agonists, T0901317 and 9-Cis-retinoic acid (9-Cis-RA). We observed that Xan suppressed hepatic ANGPTL3 expression by antagonizing the LXRα/RXR-mediated transcription. These findings suggest that Xan ameliorates dyslipidemia by modulating the LXRα/RXR-ANGPTL3-LPL axis. Xan represents a novel potential inhibitor of ANGPTL3 for the prevention or treatment of ASCVD.

Evaluation of the Protoscolicidal Activity of Humulus lupulus Methanolic Extracts on Echinococcus granulosus Sensu Stricto

The larval stage of the parasite Echinococcus granulosus sensu lato (s.l) is responsible for cystic echinococcosis (CE), a long-term infection affecting humans and animals worldwide, and constitutes a serious public health concern. If left untreated, CE can cause serious damage to multiple organs, especially the liver and lungs. Regarding the treatment, in the last few years, the use of pharmacological treatment has increased, suggesting that in the future, drug therapy may replace surgery for uncomplicated cysts. However, the only available anthelmintic drug to treat this infection is the albendazole, which has an efficacy that does not exceed 50%. On the basis of the above-mentioned evidence, new and improved alternative treatments are urgently needed. The use of natural products and their active fractions and components holds great promise as a valuable resource for the development of novel and effective therapies. Hop (Humulus lupulus L.) is a bittering agent in the brewing industry for which the sedative, digestive, anti-inflammatory, and antimicrobial effects have been reported. The purpose of this study was to assess the in vitro efficacy of methanolic extracts from the leaves of hop varieties against E. granulosus sensu stricto (s.s) protoscoleces. Varieties Mapuche and Victoria caused a stronger protoscolicidal effect compared to the Bullion, Cascade, and Traful varieties (P < 0.01), coinciding with their highest content of flavonoids, total polyphenols, and saponins. The viability of protoscoleces treated with the varieties Mapuche and Victoria decreased to approximately 50% at days 5 y 8, respectively, showing alterations such as soma contraction and impaired microtriches. After 18 days of treatment with both varieties, protoscoleces were completely altered both structurally and ultrastructurally. In conclusion, the methanolic extracts of the H. lupulus varieties Mapuche and Victoria demonstrated a marked in vitro effect against E. granulosus s.s. protoscoleces. The beer-making industry exclusively uses hop cones, leaving behind large amounts of hop leaves as an agricultural by-product that is not being utilized. On the basis of our study, we propose that hop leaves could also be used as a source of secondary metabolites with anthelmintic activity.

Eco-friendly managements and molecular mechanisms for improving postharvest quality and extending shelf life of kiwifruit: A review

Kiwifruit (Actinidia spp.) is a commercially important horticultural fruit crop worldwide. Kiwifruit contains numerous minerals, vitamins, and dietary phytochemicals, that not only responsible for the flavor but can also serve as adjuncts in the treatment of diabetes, digestive disorders, cardiovascular system, cancer and heart disease. However, fruit quality and shelf life affect consumer's acceptance and production chain. Understanding the methods of fruit storage preservation, as well as their biochemical, physiological, and molecular basis is essential. In recent years, eco-friendly (comprehensive and environmentally friendly) treatments such as hot water, ozone, chitosan, quercetin, and antifungal additive from biocontrol bacteria or yeast have been applied to improve postharvest fruit quality with longer shelf life. This review provides a comprehensive overview of the latest advancements in control measures, applications, and mechanisms related to water loss, chilling injury, and pathogen diseases in postharvest kiwifruit. Further studies should utilize genome editing techniques to enhance postharvest fruit quality and disease resistance through site-directed bio-manipulation of the kiwifruit genome.

Characteristics and Antimicrobial Activities of Iron Oxide Nanoparticles Obtained via Mixed-Mode Chemical/Biogenic Synthesis Using Spent Hop (Humulus lupulus L.) Extracts

Iron oxide nanoparticles (IONPs) have many practical applications, ranging from environmental protection to biomedicine. IONPs are being investigated due to their high potential for antimicrobial activity and lack of toxicity to humans. However, the biological activity of IONPs is not uniform and depends on the synthesis conditions, which affect the shape, size and surface modification. The aim of this work is to synthesise IONPs using a mixed method, i.e., chemical co-precipitation combined with biogenic surface modification, using extracts from spent hops (Humulus lupulus L.) obtained as waste product from supercritical carbon dioxide hop extraction. Different extracts (water, dimethyl sulfoxide (DMSO), 80% ethanol, acetone, water) were further evaluated for antioxidant activity based on the silver nanoparticle antioxidant capacity (SNPAC), total phenolic content (TPC) and total flavonoid content (TFC). The IONPs were characterised via UV-vis spectroscopy, scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS) and Fourier-transform infrared (FT-IR) spectroscopy. Spent hop extracts showed a high number of flavonoid compounds. The efficiency of the solvents used for the extraction can be classified as follows: DMSO > 80% ethanol > acetone > water. FT-IR/ATR spectra revealed the involvement of flavonoids such as xanthohumol and/or isoxanthohumol, bitter acids (i.e., humulones, lupulones) and proteins in the surface modification of the IONPs. SEM images showed a granular, spherical structure of the IONPs with diameters ranging from 81.16 to 142.5 nm. Surface modification with extracts generally weakened the activity of the IONPs against the tested Gram-positive and Gram-negative bacteria and yeasts by half. Only the modification of IONPs with DMSO extract improved their antibacterial properties against Gram-positive bacteria (Staphylococcus epidermidis, Staphylococcus aureus, Micrococcus luteus, Enterococcus faecalis, Bacillus cereus) from a MIC value of 2.5-10 mg/mL to 0.313-1.25 mg/mL.

Lactobacillus casei-derived postbiotics inhibited digestion of triglycerides, glycerol phospholipids and sterol lipids via allosteric regulation of BSSL, PTL and PLA2 to prevent obesity: perspectives on deep learning integrated multi-omics

The anti-obesity potential of probiotics has been widely reported, however their utilization in high-risk patients and potential adverse reactions have led researchers to focus their attention on postbiotics. Herein, pseudo-targeted lipidomics linked with deep learning-based metabolomics was utilized to dynamically characterize the postbiotic potential of heat-inactivated Lactobacillus casei JCM1134 supplementation after a high-fat diet in treating obesity. MG (ranged from 423.0 ± 1.4 mg L-1 to 331.45 ± 2.3 mg L-1), LPC (ranged from 13.1 ± 0.08 mg L-1 to 10.2 ± 0.1 mg L-1) and Cho (ranged from 9.0 ± 0.3 mg L-1 to 5.7 ± 0.2 mg L-1) in intestinal digestive products were significantly decreased, indicating that the digestion of lipid was inhibited. 8-C-glucosylorobol, from Lactobacillus casei, was confirmed from quantitative results and molecular simulation calculations to inhibit the transformation of TG, DG, and ChE through weakening hydrogen bonds between enzymes and substrates and reducing the binding energy. Pristimerin and 2,4-quinolinediol can effectively reduce the hydrogen bonding force between PC and phospholipase A2, which were related to the obstruction of phosphatidylcholine digestion. This research deepened the understanding of the mechanism underlying the inactivated probiotics affecting lipid digestion, establishing the critical groundwork for clinical application of probiotics in inhibiting obesity.

An Updated Review of the Genus Humulus: A Valuable Source of Bioactive Compounds for Health and Disease Prevention

The medicinal potential of hop (Humulus lupulus L.) is widely cited in ancient literature and is also allowed in several official pharmacopoeias for the treatment of a variety of ailments, mainly related to anxiety states. This is due to the plethora of phytoconstituents (e.g., bitter acids, polyphenols, prenyl flavonoids) present in the female inflorescences, commonly known as cones or strobili, endowed with anti-inflammatory, antioxidant, antimicrobial, and phytoestrogen activities. Hop has recently attracted the interest of the scientific community due to the presence of xanthohumol, whose strong anti-cancer activity against various types of cancer cells has been well documented, and for the presence of 8-prenyl naringenin, the most potent known phytoestrogen. Studies in the literature have also shown that hop compounds can hinder numerous signalling pathways, including ERK1/2 phosphorylation, regulation of AP-1 activity, PI3K-Akt, and nuclear factor NF-κB, which are the main targets of the antiproliferative action of bitter acids and prenylflavonoids. In light of these considerations, the aim of this review was to provide an up-to-date overview of the main biologically active compounds found in hops, as well as their in vitro and in vivo applications for human health and disease prevention. To this end, a quantitative literature analysis approach was used, using VOSviewer software to extract and process Scopus bibliometric data. In addition, data on the pharmacokinetics of bioactive hop compounds and clinical studies in the literature were analysed. To make the information more complete, studies on the beneficial properties of the other two species belonging to the genus Humulus, H. japonicus and H. yunnanensis, were also reviewed for the first time.

Evaluating hop extract concentrations found in commercial beer to inhibit Streptococcus mutans biofilm formation

AIMS

The purpose of this study was to compare the effect of hop extracts with diverse β-acid concentrations on Streptococcus mutans biofilm formation.

METHODS AND RESULTS

Ten different hop extracts, with α-acid concentrations similar to those found in commercial beer products and β-acid concentrations ranging from 2.6 to 8.1%, were added to distilled water to make standardized concentrations. S. mutans isolates were treated with hop extract dilutions varying from 1:2 to 1:256. The minimum inhibitory, minimum bactericidal, and minimum biofilm inhibitory concentrations were determined and the optical density was evaluated. Live/dead staining confirmed the bactericidal effects. Biofilm formation of several strains of S. mutans was significantly inhibited by hop extract dilutions of 1:2, 1:4, 1:8, 1:16, and 1:32. Strong negative correlations were observed between α- and β-acid concentrations of the hop extracts and S. mutans total growth and biofilm formation.

CONCLUSIONS

The use of hop extracts prepared similarly to commercial beer decreased S. mutans biofilm formation.

SIGNIFICANCE AND IMPACT OF THE STUDY

The inclusion of hops in the commercial beer products may provide beneficial health effects. Further studies are warranted to determine an effect in vivo on the development of dental caries.

Predictive Multi Experiment Approach for the Determination of Conjugated Phenolic Compounds in Vegetal Matrices by Means of LC-MS/MS

Polyphenols (PCs) are a numerous class of bioactive molecules and are known for their antioxidant activity. In this work, the potential of the quadrupole/linear ion trap hybrid mass spectrometer (LIT-QqQ) was exploited to develop a semi-untargeted method for the identification of polyphenols in different food matrices: green coffee, Crocus sativus L. (saffron) and Humulus lupulus L. (hop). Several conjugate forms of flavonoids and hydroxycinnamic acid were detected using neutral loss (NL) as a survey scan coupled with dependent scans with enhanced product ion (EPI) based on information-dependent acquisition (IDA) criteria. The presented approach is focused on a specific class of molecules and provides comprehensive information on the different conjugation models that are related to specific base molecules, thus allowing a quick and effective identification of all possible combinations, such as mono-, di-, or tri-glycosylation or another type of conjugation such as quinic acid esters.

QuEChERS extraction for quantitation of bitter acids and xanthohumol in hops by HPLC-UV

We hypothesised that QuEChERS could be successfully applied to the extraction of bitter acids and xanthohumol from hops, which would be less time consuming, cheaper, and more eco-friendly by the severe reduction of solvent use. High performance liquid chromatography was used to separate the compounds after extraction and quantitation was evaluated against standard calibration curves for bitter acids prepared from an International calibration extract (ICE-4) and an authentic standard of xanthohumol. The standard QuEChERS method was compared to mini and micro-versions including clean-up and spiking procedures. The quantitative analyzes indicate the applicability of the QuEChERS method for the quantitation of bitter acids compared to Soxhlet extraction. The statistical data confirm reproducibility of the total alpha- and beta- acids measured by the standard method and the modified mini- and micro-QuEChERS procedures. Our hypothesis is supported by the data described and is consistent with other previous methods described in the literature.

Dietary Phytoestrogens and Their Metabolites as Epigenetic Modulators with Impact on Human Health

The impact of dietary phytoestrogens on human health has been a topic of continuous debate since their discovery. Nowadays, based on their presumptive beneficial effects, the amount of phytoestrogens consumed in the daily diet has increased considerably worldwide. Thus, there is a growing need for scientific data regarding their mode of action in the human body. Recently, new insights of phytoestrogens’ bioavailability and metabolism have demonstrated an inter-and intra-population heterogeneity of final metabolites’ production. In addition, the phytoestrogens may have the ability to modulate epigenetic mechanisms that control gene expression. This review highlights the complexity and particularity of the metabolism of each class of phytoestrogens, pointing out the diversity of their bioactive gut metabolites. Futhermore, it presents emerging scientific data which suggest that, among well-known genistein and resveratrol, other phytoestrogens and their gut metabolites can act as epigenetic modulators with a possible impact on human health. The interconnection of dietary phytoestrogens’ consumption with gut microbiota composition, epigenome and related preventive mechanisms is discussed. The current challenges and future perspectives in designing relevant research directions to explore the potential health benefits of dietary phytoestrogens are also explored.

Modulation of Adenosine Receptors by Hops and Xanthohumol in Cell Cultures

Adenosine receptors (ARs) have been involved in neurodegenerative diseases such as Alzheimer disease, where oxidative stress contributes to neurodegeneration and cell death. Therefore, there is increasing interest in developing antioxidative strategies to avoid or reduce neurodegeneration. We have previously described that different beer extracts modulate ARs and protect glioma and neuroblastoma cells from oxidative stress. The present work aimed to analyze the possible protective effect of hops (Humulus lupulus L.), a major component of beer, and xanthohumol on cell death elicited by oxidative stress and their modulation of ARs in rat C6 glioma and human SH-SY5Y neuroblastoma cells. Different extraction methods were employed in two hops varieties (Nugget and Columbus). Cell viability was determined by the XTT method in cells exposed to these hops extracts and xanthohumol. ARs were analyzed by radioligand binding and real-time PCR assays. Hops extract reverted the cell death observed under oxidative stress and modulated adenosine A₁ and A₂ receptors in both cell types. Xanthohumol was unable to revert the effect of oxidative stress in cell viability but it also modulated ARs similarly to hops. Therefore, healthy effects of beer described previously could be due, at least in part, to their content of hops and the modulation of ARs.

Optimized Supercritical CO2 Extraction Enhances the Recovery of Valuable Lipophilic Antioxidants and Other Constituents from Dual-Purpose Hop (Humulus lupulus L.) Variety Ella

The article presents the optimization of supercritical CO₂ extraction (SFE-CO₂) parameters using response surface methodology (RSM) with central composite design (CCD) in order to produce single variety hop (cv. Ella) extracts with high yield and strong in vitro antioxidant properties. Optimized SFE-CO₂ (37 MPa, 43 °C, 80 min) yielded 26.3 g/100 g pellets of lipophilic fraction. This extract was rich in biologically active α- and β-bitter acids (522.8 and 345.0 mg/g extract, respectively), and exerted 1481 mg TE/g extract in vitro oxygen radical absorbance capacity (ORAC). Up to ~3-fold higher extraction yield, antioxidant recovery (389.8 mg TE/g pellets) and exhaustive bitter acid extraction (228.4 mg/g pellets) were achieved under the significantly shorter time compared to the commercially used one-stage SFE-CO₂ at 10–15 MPa and 40 °C. Total carotenoid and chlorophyll content was negligible, amounting to <0.04% of the total extract mass. Fruity, herbal, spicy and woody odor of extracts could be attributed to the major identified volatiles, namely β-pinene, β-myrcene, β-humulene, α-humulene, α-selinene and methyl-4-decenoate. Rich in valuable bioactive constituents and flavor compounds, cv. Ella hop SFE-CO₂ extracts could find multipurpose applications in food, pharmaceutical, nutraceutical and cosmetics industries.

Xanthohumol prolongs lifespan and decreases stress-induced mortality in Drosophila melanogaster

Aging is a significant risk factor that links to the genesis of human diseases. The capacity to scavenge free radicals and adapt to various stresses is essential for expanding living organisms' lifespan. The evidences on the promotion of longevity by dietary supplementation are growing. Drosophila or fruit fly is one of the most effective models for the evaluation of anti-aging compounds. Xanthohumol (XN) is a potential bioactive substance for the prevention and treatment of many diseases. The previous studies have reported its potent activities as antioxidant, anticancer, anti-inflammatory, antiviral, antibacterial antiplasmodial, and antiobesity. In this study, the effect of XN supplementation on the lifespan extension was investigated in Drosophila melanogaster. The effects of XN on the improvement of the recovery from cold and heat shock, the resistance to starvation stress, and free radical-induced oxidative stress in XN-treated flies were also evaluated. Results showed that supplementation with XN at 0.5 mg/mL diet extended the mean lifespan by 14.89%. This was consistent with a significant improvement of locomotor activity of the Drosophila fed with an XN-mixed diet compared with those fed with a control diet. XN supplementation significantly increased the antioxidant enzyme activities at both 25 and 40 days. Drosophila treated with XN exhibited increased survival after exposure to hydrogen peroxide and paraquat. Finally, XN supplementation improved the recovery from cold and heat shock, the resistance to starvation stress, and acetic acid-induced stress. The present study shows that dietary supplementation with XN revealed the longevity effect and ameliorated stress-induced mortality in Drosophila.

Adult Male Rats Show Resilience to Adolescent Bisphenol A Effects on Hormonal and Behavioral Responses While Co-Exposure With Hop Extracts Supports Synergistic Actions

The adolescence period, marked by sexual and brain maturation, has shown sensitivity to various environmental disruptors. Exposure to the xenoestrogen bisphenol A (BPA) is known to alter physiological and behavioral responses although its role at this critical period remains largely unknown. Recent research further suggests biochemical and genomic effects of BPA to be mitigated by various natural compounds, while effects on behavior have not been examined. This study aimed to characterize (1) the effects of dietary BPA during adolescence on endogenous corticosterone (CORT) secretion, emotional behavior, and testosterone (T) in adulthood, and (2) the impact of combined exposure to BPA with hop extracts (Hop), a phytoestrogen with anxiolytic properties. To do so, four groups of male Wistar rats [postnatal day (PND) 28] were administered corn oil (control), BPA (40 mg/kg), hops (40 mg/kg), or BPA-hops by oral gavage for 21 days (PND 28–48). Blood droplets collected on PND 28, 48, and 71 served to measure CORT and T changes. As adults, rats were tested in the elevated plus maze (EPM), the social interaction test, and the forced swim test. Our findings demonstrated elevated anxiety and a trend toward depressive-like behaviors in BPA- compared to hops-exposed rats. However, BPA intake had no impact on basal CORT levels, or adulthood T secretion and sociability. Of note, BPA's anxiogenic effect manifested through decreased EPM open arm entries was abolished by hops co-supplementation. Together, our observations suggest the adolescence period to be less sensitive to deleterious effects of BPA than what has been reported upon gestational and perinatal exposure.

Xanthohumol for Human Malignancies: Chemistry, Pharmacokinetics and Molecular Targets

Xanthohumol (XH) is an important prenylated flavonoid that is found within the inflorescence of Humulus lupulus L. (Hop plant). XH is an important ingredient in beer and is considered a significant bioactive agent due to its diverse medicinal applications, which include anti-inflammatory, antimicrobial, antioxidant, immunomodulatory, antiviral, antifungal, antigenotoxic, antiangiogenic, and antimalarial effects as well as strong anticancer activity towards various types of cancer cells. XH acts as a wide ranging chemopreventive and anticancer agent, and its isomer, 8-prenylnaringenin, is a phytoestrogen with strong estrogenic activity. The present review focuses on the bioactivity of XH on various types of cancers and its pharmacokinetics. In this paper, we first highlight, in brief, the history and use of hops and then the chemistry and structure–activity relationship of XH. Lastly, we focus on its prominent effects and mechanisms of action on various cancers and its possible use in cancer prevention and treatment. Considering the limited number of available reviews on this subject, our goal is to provide a complete and detailed understanding of the anticancer effects of XH against different cancers.

Functional polysaccharide-based film prepared from chitosan and β-acids: Structural, physicochemical, and bioactive properties

β-Acids are natural antibacterial and antioxidant ingredients, obtained from supercritical CO₂ hop extract. In this study, β-acids/chitosan complex films were prepared using the casting method. Complex films were characterized using scanning electron microscopy (SEM), atomic force microscope (AFM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction analysis (XRD). Structure analysis revealed that β-acids can be successfully combined with the chitosan matrix. Mechanical tests demonstrated that the tensile strength of the films showed a significant upward trend (1.9 MPa to 9.6 MPa) with increase in β-acids content (0.1%-0.3%). Interestingly, the chitosan-based films showed excellent UV barrier capability below 400 nm. The release of β-acids from the film followed Fickian diffusion (n < 0.45). In addition, the complex films inhibited the growth of five food-borne pathogens (Escherichia coli, Staphylococcus aureus, Bacillus subtilis, Salmonella enteritidis and Listeria monocytogenes). This study highlights the promising nature of composite film as a desirable alternative for active packaging.

Quantitative Analysis of Prenylated Constituents in Commercial Hops Samples Using Ultrahigh-Performance Supercritical Fluid Chromatography

The importance of hops (the flowers of Humulus lupulus) as food and an herbal remedy is reflected by a large number of analytical methods published. However, supercritical fluid chromatography, a highly efficient, rapid, and "green" separation technique, has not been considered for hops samples so far. This prompted us to establish the first supercritical fluid chromatography-based protocol for the separation, identification, and quantitation of five prenylated constituents of hops. Hulupinic acid ( 1: ), a prominent oxidation product of hop acids, three flavanones, i.e., 8-prenylnaringenin ( 2: ), 6-prenylnaringenin ( 3: ), and isoxanthohumol ( 4: ), as well as the chalcone xanthohumol ( 5: ) could be baseline separated in less than 5 minutes using a Viridis BEH 2-EP column (3.0 × 100 mm; 1.7 µm particle size) and a mobile phase consisting of CO₂ and isopropanol. Good results regarding selectivity, accuracy (recovery rates: 85.0 - 113.1%), precision (intra-day ≤ 2.1%, inter-day ≤ 3.5%), and linearity (R² ≥ 0.99) were obtained for both photodiode array and mass detection. The lowest detection limit at 220 nm was at 0.1 µg/mL ( 1, 3: , and 4: ), with mass detection even at 0.001 µg/mL ( 4: ). As an application example of the validated method, the five hops constituents were quantified in three dietary supplements, one herbal medicinal product, and two batches of hop flowers (Lupuli flos). In most samples analyzed, the major component was 5: (0.01 - 1.02%), whereas the major component in Lupuli flos samples was compound 1: (0.12 - 0.21%). This protocol offers a fast and environmentally friendly alternative to liquid chromatography for the quality control of hops.

Traditional Chinese medicine may be further explored as candidate drugs for pancreatic cancer: A review

Pancreatic cancer is a disease with a high mortality rate. Although survival rates for different types of cancers have improved in recent years, the five-year survival rate of pancreatic cancer stands at 8%. Moreover, the current first-line therapy, gemcitabine, results in low remission rates and is associated with drug resistance problems. Alternative treatments for pancreatic cancer such as surgery, chemotherapy and radiation therapy provide marginal remission and survival rates. This calls for the search of more effective drugs or treatments. Traditional Chinese medicine contains numerous bioactive ingredients some of which show activity against pancreatic cancer. In this review, we summarize the mechanisms of five types of traditional Chinese medicine monomers. In so-doing, we provide new potential drug candidates for the treatment of pancreatic cancer.

Flavonoids as Phytoestrogenic Components of Hops and Beer

The value of hops (Humulus lupulus L.) in beer production has been undisputed for centuries. Hops is rich in humulones and lupulones which gives the characteristic aroma and bitter taste, and preserves this golden drink against growing bacteria and molds. Besides α- and β-acids, the lupulin glands of hop cones excrete prenylated flavonoids, which exhibit a broad spectrum of biological activities and therefore has therapeutic potential in humans. Recently, interest in hops was raised due to hop prenylated flavanones which show extraordinary estrogen activities. The strongest known phytoestrogen so far is 8-prenylnaringenin (8-PN), which along with 6-prenylanaringenin (6-PN), 6,8-diprenylnaringenin (6,8-DPN) and 8-geranylnaringenin (8-GN) are fundamental for the potent estrogen activity of hops. This review provides insight into the unusual hop phytoestrogens and shows numerous health benefits associated with their wide spectrum of biological activities including estrogenic, anticancer, neuropreventive, antinflamatory, and antimicrobial properties, which were intensively studied, and potential applications of these compounds such as, as an alternative to hormone replacement therapy (HRT).

Xanthohumol Inhibits the Growth of Keratin 18-Overexpressed Esophageal Squamous Cell Carcinoma in vitro and in vivo

Esophageal squamous cell carcinoma (ESCC) is a leading cause of cancer-related death worldwide. Xanthohumol is a prenylated flavonoid isolated from hops. Although xanthohumol has been reported to exert anti-obesity, hypoglycemic, anti-hyperlipidemia and anti-cancer activities, the mechanisms underlying its chemotherapeutic activity are yet to be elucidated. In the present study, we found that xanthohumol inhibited ESCC cell proliferation in vitro and in vivo by targeting keratin (KRT)-18. Xanthohumol suppressed the proliferation, foci formation, and anchorage-independent colony growth of KYSE30 cells. Using xanthohumol-sepharose conjugated bead pull-down and mass/mass analysis, we found that KRT18 is a novel target of xanthohumol in KYSE30 cells. KRT18 protein was highly expressed in patient ESCC tissues compared to adjunct tissues. Anti-proliferative activity of xanthohumol was abrogated or enhanced according to the knockdown or overexpression of KRT18 protein, respectively. Xanthohumol also induced apoptosis and cell cycle arrest at G1 phase which was associated with the modulation of expression of related makers including cyclin D1, cyclin D3, and cleaved-PARP, Bcl-2, cytochrome c and Bax. While xanthohumol attenuated KRT18 protein expression, it failed to cause any change in the KRT18 mRNA level. Furthermore, oral administration of xanthohumol decreased tumor volume and weight in patient-derived xenografts (PDXs) tumors having overexpressed KRT18. Overall these results suggest that xanthohumol acts as a KRT18 regulator to suppress the growth of ESCC.

Xanthohumol regulates miR-4749-5p-inhibited RFC2 signaling in enhancing temozolomide cytotoxicity to glioblastoma

AIMS

Xanthohumol (XN), a natural prenylated flavonoid isolated from Humulus lupulus L. (hops), possess the therapeutic effects in glioblastoma multiforme (GBM), which is a grade IV aggressive glioma in adults. However, low bioavailability and extractive yield limit the clinical applications of XN. To comprehensively investigate XN-mediated gene networks in inducing cell death is helpful for drug development and cancer research. Therefore, we aim to identify the detailed molecular mechanisms of XN's effects on exhibiting cytotoxicity for GBM therapy.

METHODS AND KEY FINDINGS

XN significantly induced GBM cell death and enhanced temozolomide (TMZ) cytotoxicity, a first-line therapeutic drug of GBM. XN-mediated transcriptome profiles and canonical pathways were identified. DNA repair signaling, a well-established mechanism against TMZ cytotoxicity, was significantly correlated with XN-downregulated genes. Replication factor C subunit 2 (RFC2), a DNA repair-related gene, was obviously downregulated in XN-treated cells. Higher RFC2 levels which occupied poor patient survival were also observed in high grade GBM patients and tumors. Inhibition of RFC2 reduced cell viability, induced cell apoptosis, and enhanced both XN and TMZ cytotoxicity. By intersecting array data, bioinformatic prediction, and in vitro experiments, microRNA (miR)-4749-5p, a XN-upregulated microRNA, was identified to target to RFC2 3'UTR and inhibited RFC2 expression. A negative correlation existed between miR-4749-5p and RFC2 in GBM patients. Overexpression of miR-4749-5p significantly promoted XN- and TMZ-mediated cytotoxicity, and reduced RFC2 levels.

SIGNIFICANCE

Consequently, we suggest that miR-4749-5p targeting RFC2 signaling participates in XN-enhanced TMZ cytotoxicity of GBM. Our findings provide new potential therapeutic directions for future GBM therapy.

Promotion of ubiquitination-dependent survivin destruction contributes to xanthohumol-mediated tumor suppression and overcomes radioresistance in human oral squamous cell carcinoma

Background

Overexpression of survivin plays a crucial role in tumorigenesis and correlates with poor prognosis in human malignancies. Thus, survivin has been proposed as an attractive target for new anti-tumor interventions.

Methods

A natural product library was used for natural compound screening through MTS assay. The expression of survivin in oral squamous cell carcinoma (OSCC) and the inhibitory effect of xanthohumol (XN) on OSCC were examined by anchorage-dependent and -independent growth assays, immunoblot, immunofluorescence, immunohistochemical staining, ubiquitination analysis, co-immunoprecipitation assay, CRISPR-Cas9-based gene knockout, and xenograft experiment.

Results

Survivin is highly expressed in OSCC patient-derived tissues and cell lines. Knockout of survivin reduced the tumorigenic properties of OSCC cells in vitro and in vivo. With a natural compound screening, we identified that xanthohumol inhibited OSCC cells by reducing survivin protein level and activating mitochondrial apoptotic signaling. Xanthohumol inhibited the Akt-Wee1-CDK1 signaling, which in turn decreased survivin phosphorylation on Thr34, and facilitated E3 ligase Fbxl7-mediated survivin ubiquitination and degradation. Xanthohumol alone or in combination with radiation overcame radioresistance in OSCC xenograft tumors.

Conclusion

Our findings indicate that targeting survivin for degradation might a promising strategy for OSCC treatment.

A New Perspective on the Health Benefits of Moderate Beer Consumption: Involvement of the Gut Microbiota

Beer is the most widely consumed fermented beverage in the world. A moderate consumption of beer has been related to important healthy outcomes, although the mechanisms have not been fully understood. Beer contains only a few raw ingredients but transformations that occur during the brewing process turn beer into a beverage that is enriched in micronutrients. Beer also contains an important number of phenolic compounds and it could be considered to be a source of dietary polyphenols. On the other hand, gut microbiota is now attracting special attention due to its metabolic effects and as because polyphenols are known to interact with gut microbiota. Among others, ferulic acid, xanthohumol, catechins, epicatechins, proanthocyanidins, quercetin, and rutin are some of the beer polyphenols that have been related to microbiota. However, scarce literature exists about the effects of moderate beer consumption on gut microbiota. In this review, we focus on the relationship between beer polyphenols and gut microbiota, with special emphasis on the health outcomes.