Synergistic Anticancer Activity of Plumbagin and Xanthohumol Combination on Pancreatic Cancer Models.

Among diverse cancers, pancreatic cancer is one of the most aggressive types due to inadequate diagnostic options and treatments available. Therefore, there is a necessity to use combination chemotherapy options to overcome the chemoresistance of pancreatic cancer cells. Plumbagin and xanthohumol, natural compounds isolated from the Plumbaginaceae family and Humulus lupulus, respectively, have been used to treat various cancers. In this study, we investigated the anticancer effects of a combination of plumbagin and xanthohumol on pancreatic cancer models, as well as the underlying mechanism. We have screened in vitro numerous plant-derived extracts and compounds and tested in vivo the most effective combination, plumbagin and xanthohumol, using a transgenic model of pancreatic cancer KPC (KrasLSL.G12D/+; p53R172H/+; PdxCretg/+). A significant synergistic anticancer activity of plumbagin and xanthohumol combinations on different pancreatic cancer cell lines was found. The combination treatment of plumbagin and xanthohumol influences the levels of B-cell lymphoma (BCL2), which are known to be associated with apoptosis in both cell lysates and tissues. More importantly, the survival of a transgenic mouse model of pancreatic cancer KPC treated with a combination of plumbagin and xanthohumol was significantly increased, and the effect on BCL2 levels has been confirmed. These results provide a foundation for a potential new treatment for pancreatic cancer based on plumbagin and xanthohumol combinations.

Xanthohumol ameliorates drug-induced hepatic ferroptosis via activating Nrf2/xCT/GPX4 signaling pathway.

BACKGROUND: As a canonical iron-dependent form of regulated cell death (RCD), ferroptosis plays a crucial role in chemical-induced liver injuries. Previous studies have demonstrated that xanthohumol (Xh), a natural prenylflavonoid isolated from hops, exhibits anti-inflammatory, anti-antioxidative and hepatoprotective properties. However, the regulatory effects of Xh on hepatic ferroptosis and the underlying mechanism have not yet been fully elucidated. PURPOSE: To investigate the hepatoprotective effects of Xh against drug-induced liver injury (DILI) and the regulatory effects of Xh on hepatic ferroptosis, as well as to reveal the underlying molecular mechanisms. METHODS/STUDY DESIGN: The hepatoprotective benefits of Xh were investigated in APAP-induced liver injury (AILI) mice and HepaRG cells. Xh was administered intraperitoneally to assess its in vivo effects. Histological and biochemical studies were carried out to evaluate liver damage. A series of ferroptosis-related markers, including intracellular Fe2+ levels, ROS and GSH levels, the levels of MDA, LPO and 4-HNE, as well as the expression levels of ferroptosis-related proteins and modulators were quantified both in vivo and in vitro. The modified peptides of Keap1 by Xh were characterized utilizing nano LC-MS/MS. RESULTS: Xh remarkably suppresses hepatic ferroptosis and ameliorates AILI both in vitro and in vivo, via suppressing Fe2+ accumulation, ROS formation, MDA generation and GSH depletion, these observations could be considerably mitigated by the ferroptosis inhibitor ferrostatin-1 (Fer-1). Mechanistically, Xh could significantly activate the Nrf2/xCT/GPX4 signaling pathway to counteract AILI-induced hepatocyte ferroptosis. Further investigations showed that Xh could covalently modify three functional cysteine residues (cys151, 273, 288) of Keap1, which in turn, reduced the ubiquitination rates of Nrf2 and prolonged its degradation half-life. CONCLUSIONS: Xh evidently suppresses hepatic ferroptosis and ameliorates AILI via covalent modifying three key cysteines of Keap1 and activating Nrf2/xCT/GPX4 signaling pathway.

Compounds derived from Humulus lupulus inhibit SARS-CoV-2 papain-like protease and virus replication.

BACKGROUND: Selected natural compounds exhibit very good antiviral properties. Especially, the medicinal plant Humulus lupulus (hop) contains several secondary plant metabolites some of which have previously shown antiviral activities. Among them, the prenylated chalcone xanthohumol (XN) demonstrated to be a potent inhibitor of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) main protease (Mpro). HYPOTHESIS/PURPOSE: Following the finding that xanthohumol (XN) is a potent inhibitor of SARS-CoV-2 Mpro, the effect of XN and its major derivatives isoxanthohumol (IXN), 6-prenylnaringenin (6-PN), and 8-prenylnaringenin (8-PN) from hops on SARS-CoV-2 papain-like protease (PLpro) were investigated. STUDY DESIGN: The modulatory effect of the hop compounds on PLpro were studied first in silico and then in vitro. In addition, the actual effect of hop compounds on the replication of SARS-CoV-2 in host cells was investigated. METHODS: In silico docking analysis was used to predict the binding affinity of hop compounds to the active site of PLpro. A recombinant PLpro was cloned, purified, characterized, and analyzed by small-angle X-ray scattering (SAXS), deISGylation assays, and kinetic analyses. Antiviral activity of hop compounds was assessed using the fluorescently labeled wildtype SARS-CoV-2 (icSARS-CoV-2-mNG) in Caco-2 host cells. RESULTS: Our in silico docking suggests that the purified hop compounds bind to the active site of SARS-CoV-2 PLpro blocking the access of its natural substrates. The hop-derived compounds inhibit SARS-CoV-2 PLpro with half maximal inhibitory concentration (IC50) values in the range of 59-162 µM. Furthermore, we demonstrate that XN and 6-PN, in particular, impede viral replication with IC50 values of 3.3 µM and 7.3 µM, respectively. CONCLUSION: In addition to the already known inhibition of Mpro by XN, our results show, for the first time, that hop-derived compounds target also SARS-CoV-2 PLpro which is a promising therapeutic target as it contributes to both viral replication and modulation of the immune system. These findings support the possibility to develop new hop-derived antiviral drugs targeting human coronaviruses.

Chemical compositions and sleep-promoting activities of hop (Humulus lupulus L.) varieties.

Among natural products with sleep-promoting activity, hops have been used since ancient times as a tranquilizer and hypnotic agent. This study investigated the sleep-promoting effects of extracts of various hop (Humulus lupulus L.) varieties in invertebrate and vertebrate models. The content of α-acids, ß-acids, and xanthohumol was higher in hop 70% alcohol extracts than in hop hot water extracts. Among the alcohol extracts, Citra contained a high α-acid content (229.32 µg/mg), while Saphir showed high ß-acid and xanthohumol content (66.37 and 4.23 µg/mg, respectively). In Drosophila melanogaster, Simcoe and Mosaic water extracts and Saphir and Simcoe alcohol extracts significantly increased total nighttime sleep. Total sleep time of mice with pentobarbital-induced sleep was significantly increased by Simcoe and Mosaic water extracts and Saphir and Simcoe ethanol extracts compared to the normal group. Oral administration of Simcoe water extract and Saphir alcohol extract improved sleep in the caffeine-induced insomnia model and upregulated the mRNA expression of GABAA (gamma 2 subunit) and GABAB receptors in mouse brains. Additionally, Saphir alcohol extract significantly increased the GABA content in mouse brains. Simcoe water extract and Saphir ethanol extract modulated GABAergic signaling to improve sleep-related behaviors, including sleep duration.

Preparation of green colorimetric pH sensor using Humulus lupulus L. (common hop) biomolecular extract for sweat monitoring.

Novel smart cotton diagnostic assay was developed toward onsite sensing of sweat pH variations for possible medical applications such as drug test and healthcare purposes. Humulus lupulus L. extract was obtained according to previously reported procedure. As reported by high-performance liquid chromatography (HPLC), the extract demonstrated the presence of hop acids, prenylchalcones, and prenylflavanones, which is responsible for the colorimetric changes. The extract was applied to cellulose fibers employing potassium aluminum sulfate as mordant. This was observed by the formation of mordant/xanthohumol nanoparticles onto cotton surface. The absorption spectra and CIE (Commission Internationale de l'Eclairage) Lab screening of the prepared cotton assay showed colorimetric changes in association with hypsochromic shift from 600 nm to 433 nm upon exposure to sweat simulant fluid (pH < 7). The biochromic activity of the xanthohumol-finished cotton depends mainly on the halochromic performance of the xanthohumol chromophore to show a colorimetric switch from yellow to white owing to intramolecular charge transfer in the xanthohumol molecule. No substantial defects were detected in gas-permeability and stiffness of the treated fabrics. Satisfactory fastness was approved for the xanthohumol-dyed diagnostic cotton assay.

Xanthohumol inhibits non-small cell lung cancer via directly targeting T-lymphokine-activated killer cell-originated protein kinase.

Xanthohumol is a principal prenylated chalcone isolated from hops. Previous studies have shown that xanthohumol was effective against various types of cancer, but the mechanisms, especially the direct targets for xanthohumol to exert an anticancer effect, remain elusive. Overexpression of T-lymphokine-activated killer cell-originated protein kinase (TOPK) promotes tumorigenesis, invasion and metastasis, implying the likely potential for targeting TOPK in cancer prevention and treatment. In the present study, we found that xanthohumol significantly inhibited the cell proliferation, migration and invasion of non-small cell lung cancer (NSCLC) in vitro and suppressed tumor growth in vivo, which is well correlated with inactivating TOPK, evidenced by reduced phosphorylation of TOPK and its downstream signaling histone H3 and Akt, and decreased its kinase activity. Moreover, molecular docking and biomolecular interaction analysis showed that xanthohumol was able to directly bind to the TOPK protein, suggesting that TOPK inactivation by xanthohumol is attributed to its ability to directly interact with TOPK. The findings of the present study identified TOPK as a direct target for xanthohumol to exert its anticancer activity, revealing novel insight into the mechanisms underlying the anticancer activity of xanthohumol.

Humulus lupulus L. extract and its active constituent xanthohumol attenuate oxidative stress and nerve injury induced by iron overload via activating AKT/GSK3ß and Nrf2/NQO1 pathways.

Hops, the dried female clusters from Humulus lupulus L., have traditionally been used as folk medicines for treating insomnia, neuralgia, and menopausal disorders. However, its pharmacological action on iron overload induced nerve damage has not been investigated. This study aims to evaluate the protective effects of hops extract (HLE) and its active constituent xanthohumol (XAN) on nerve injury induced by iron overload in vivo and in vitro, and to explore its underlying mechanism. The results showed that HLE and XAN significantly improved the memory impairment of iron overload mice, mainly manifested as shortened latency time, increased crossing platform times and spontaneous alternation ratio, and increased the expression of related proteins. Additionally, HLE and XAN significantly increased superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) activities, and remarkably decreased malondialdehyde (MDA) level in hippocampus. Also, HLE and XAN apparently reduced reactive oxygen species (ROS) content of PC12 cells induced by iron dextran (ID), and improved the oxidative stress level. Moreover, HLE and XAN significantly upregulated the expression of nuclear factor E2-related factor (Nrf2), NAD(P)H quinone oxidoreductase (NQO1), heme oxygenase-1 (HO-1), SOD, phosphorylated AKT (p-AKT), and phosphorylated GSK3ß (p-GSK3ß) both in hippocampus and PC12 cells. These findings demonstrated the protective effect of HLE and XAN against iron-induced memory impairment, which is attributed to its antioxidant profile by activation of AKT/GSK3ß and Nrf2/NQO1 pathways. Also, it was suggested that hops could be a potential candidate for iron overload-related neurological diseases treatment.

Cell death regulation: A new way for natural products to treat osteoporosis.

Osteoporosis is a common metabolic bone disease that results from the imbalance of homeostasis within the bone. Intra-bone homeostasis is dependent on a precise dynamic balance between bone resorption by osteoclasts and bone formation by mesenchymal lineage osteoblasts, which comprises a series of complex and highly standardized steps. Programmed cell death (PCD) (e.g., apoptosis, autophagy, ferroptosis, pyroptosis, and necroptosis) is a cell death process that involves a cascade of gene expression events with tight structures. These events play a certain role in regulating bone metabolism by determining the fate of bone cells. Moreover, existing research has suggested that natural products derived from a wide variety of dietary components and medicinal plants modulate the PCDs based on different mechanisms, which show great potential for the prevention and treatment of osteoporosis, thus revealing the emergence of more acceptable complementary and alternative drugs with lower costs, fewer side effects and more long-term application. Accordingly, this review summarizes the common types of PCDs in the field of osteoporosis. Moreover, from the perspective of targeting PCDs, this review also discussed the roles of currently reported natural products in the treatment of osteoporosis and the involved mechanisms. Based on this, this review provides more insights into new molecular mechanisms of osteoporosis and provides a reference for developing more natural anti-osteoporosis drugs in the future.

Computation-Assisted Identification of Bioactive Compounds in Botanical Extracts: A Case Study of Anti-Inflammatory Natural Products from Hops.

The slow pace of discovery of bioactive natural products can be attributed to the difficulty in rapidly identifying them in complex mixtures such as plant extracts. To overcome these hurdles, we explored the utility of two machine learning techniques, i.e., Elastic Net and Random Forests, for identifying the individual anti-inflammatory principle(s) of an extract of the inflorescences of the hops (Humulus lupulus) containing hundreds of natural products. We fractionated a hop extract by column chromatography to obtain 40 impure fractions, determined their anti-inflammatory activity using a macrophage-based bioassay that measures inhibition of iNOS-mediated formation of nitric oxide, and characterized the chemical composition of the fractions by flow-injection HRAM mass spectrometry and LC-MS/MS. Among the top 10 predictors of bioactivity were prenylated flavonoids and humulones. The top Random Forests predictor of bioactivity, xanthohumol, was tested in pure form in the same bioassay to validate the predicted result (IC50 7 µM). Other predictors of bioactivity were identified by spectral similarity with known hop natural products using the Global Natural Products Social Networking (GNPS) algorithm. Our machine learning approach demonstrated that individual bioactive natural products can be identified without the need for extensive and repetitive bioassay-guided fractionation of a plant extract.

Analysis of the Leaves and Cones of Lithuanian Hops (Humulus lupulus L.) Varieties by Chromatographic and Spectrophotometric Methods.

This work involves a comprehensive chemical composition analysis of leaf and cone samples of Lithuanian hop varieties. This study aimed to determine the chemometric properties of the leaves and cones of five Lithuanian hop varieties. Determined properties were the following: (a) xanthohumol content, (b) phenolic compounds, (c) flavonoids, (d) radical scavenging activity, and (e) the qualitative composition of volatile compounds. The total content of phenolic compounds in aqueous 75% methanolic extracts varied between 31.4-78.2 mg of rutin equivalents (RE)/g, and the concentration of flavonoids was between 11.0-23.3 mg RE/g. Radical scavenging activity varied between 34.4-87.2 mg RE/g. A QUENCHER analysis procedure showed 91.7-168.5 mg RE/g of the total phenolic compound content, 12.7-21.4 mg RE/g of flavonoids, and 48.4-121.0 mg RE/g of radical scavenging activity. 'Fredos taurieji' and 'Fredos derlingieji' varieties have shown maximum values of phenolic compounds and radical scavenging activity both in leaf and cone suspensions. These varieties accumulated a higher amount of xanthohumol in leaves. The concentration of xanthohumol in the samples varied between 0.0014-0.2136% of dry mass, with the highest concentration in the cones of 'Kauno grazieji'. We identified 19 volatile compounds in leaves, and in cones, we identified 32. In both of them, α-humulene and ß caryophyllene dominated. 'Raudoniai' leaves were exceptional in their aroma due to dominating compound nagina ketone (Kovats index 1306). The QUENCHER procedure has shown a great potential for the unextractable residue of hop raw material. Further investigation and valorization of different hop biomass components, not only cones, are essential.

Xanthohumol: An underestimated, while potent and promising chemotherapeutic agent in cancer treatment.

Today, there is a growing interest nowadays in the use of herbal substances as cancer therapeutic agents. Over recent years, Xanthohumol (XTL) has been brought out as a prenylated chalcone that is found in hops (Humulus lupulus) and beer. XTL is being investigated for its potential properties, and it has been found to have various biological effects, including anti-microbial, anti-viral, and immunomodulatory. Other than these biological effects, it has also been found that XTL exerts anti-tumor effects. In the beginning, XTL, by modulating cell signaling pathways, including ERK, AKT, NF-κB, AMPK, Wnt/ß-catenin, and Notch signaling in cancer cells, inhibits tumor cell functions. Moreover, XTL, by inducing apoptotic pathways, either intrinsic or extrinsic, promotes cancer cell death and arrests the cell cycle. Furthermore, XTL inhibits metastasis, angiogenesis, cancer stemness, drug resistance, cell respiration, etc., which results in tumor aggressiveness inhibition. XTL has low solubility in water, and it has been hypothesized that some modifications, including biotinylation, can improve its pharmacogenetic characteristics. Additionally, XTL derivates such as dihydroXTL and tetrahydroXTL can be helpful for more anti-tumor activities. Using XTL with other anti-tumor agents is another approach to overcome tumor cell resistance. XTL or its derivatives, it is believed, might provide novel chemotherapeutic methods in future cancer therapy.

Antibacterial effects of biologically active ingredients in hop provide promising options to fight infections by pathogens including multi-drug resistant bacteria.

Antibiotic resistance constitutes a global threat to the health care systems. The number of infections due to multidrug-resistant (MDR) bacteria increases progressively resulting in an estimated annual number of 750,000 fatal cases worldwide. Additionally, the lack of novel antibiotic compounds worsens the dilemma. Hence, there is an urgent need for alternative ways to fight antibiotic resistance. One option may be natural compounds with antibacterial properties such as hop and its biologically active ingredients which are used in traditional medicine since ancient times. This prompted us to perform an actual literature survey regarding the antibacterial properties of biologically active ingredients in hop including humulone, lupulone and xanthohumol. The 20 included studies revealed that lupulone and xanthohumol do in fact inhibit the growth of Gram-positive bacteria in vitro. In combination with distinct antibiotic compounds the hop ingredients can even exert synergistic effects resulting in enhanced antibiotic activities against defined Gram-positive and Gram-negative bacteria. In conclusion, biologically active ingredients in hop including lupulone and xanthohumol may be potential antibiotic compounds which either alone or in combination with other antibacterial substances open novel avenues in the combat of infections caused by pathogenic including MDR bacteria.

The Potent Phytoestrogen 8-Prenylnaringenin: A Friend or a Foe?

8-prenylnaringenin (8-PN) is a prenylated flavonoid, occurring, in particular, in hop, but also in other plants. It has proven to be one of the most potent phytoestrogens in vitro known to date, and in the past 20 years, research has unveiled new effects triggered by it in biological systems. These findings have aroused the hopes, expectations, and enthusiasm of a "wonder-drug" for a host of human diseases. However, the majority of 8-PN effects require such high concentrations that they cannot be reached by normal dietary exposure, only pharmacologically; thus, adverse impacts may also emerge. Here, we provide a comprehensive and up-to-date review on this fascinating compound, with special reference to the range of beneficial and untoward health consequences that may ensue from exposure to it.

Hops extract and xanthohumol ameliorate bone loss induced by iron overload via activating Akt/GSK3ß/Nrf2 pathway.

INTRODUCTION: Osteoporosis is closely related to iron metabolism. This study aimed to investigate whether hops extract (HLE) and its active component xanthohumol (XAN) could ameliorate bone loss caused by iron overload, and explored its potential mechanism. MATERIALS AND METHODS: Iron overload mice induced by iron dextran (ID) were used in vivo, and were treated with HLE and XAN for 3 months. Bone micro-structure and bone morphology parameters were determined by Micro-CT and TRAP staining. Bone metabolism markers and oxidation indexes in serum and bone tissue were evaluated. For in vitro experiment, bone formation indexes were determined. Moreover, the expression of key proteins in protein kinase B (Akt)/glycogen synthetase kinase 3ß (GSK3ß)/nuclear factor E2-related (Nrf2) pathway was evaluated by Western blotting. RESULTS: HLE and XAN effectively improved the bone micro-structure of the femur in mice, altered bone metabolism biomarkers, and regulated the expression of proteins related to bone metabolism. Additionally, they significantly promoted cell proliferation, runt-related gene 2 (Runx2) expression, and increased ALP activity in ID-induced osteoblasts. Moreover, HLE and XAN markedly inhibited the increase of oxidative stress caused by iron overload in vivo and in vitro. Further studies showed that they significantly up-regulated the expression of p-Akt, p-GSK3ß, nuclear-Nrf2, NAD(P)H: quinone oxidoreductase 1 (NQO1), and heme oxygenase-1 (HO-1) in ID-induced osteoblasts. CONCLUSION: These findings indicated hops and xanthohumol could ameliorate bone loss induced by iron overload via activating Akt/GSK3ß/Nrf2 pathway, which brought up a novel sight for senile osteoporosis therapy.

Redox and Anti-Inflammatory Properties from Hop Components in Beer-Related to Neuroprotection.

Beer is a fermented beverage widely consumed worldwide with high nutritional and biological value due to its bioactive components. It has been described that both alcoholic and non-alcoholic beer have several nutrients derived from their ingredients including vitamins, minerals, proteins, carbohydrates, and antioxidants that make beer a potential functional supplement. Some of these compounds possess redox, anti-inflammatory and anticarcinogenic properties making the benefits of moderate beer consumption an attractive way to improve human health. Specifically, the hop cones used for beer brewing provide essential oils, bitter acids and flavonoids that are potent antioxidants and immune response modulators. This review focuses on the redox and anti-inflammatory properties of hop derivatives and summarizes the current knowledge of their neuroprotective effects.

Xanthohumol ameliorates memory impairment and reduces the deposition of ß-amyloid in APP/PS1 mice via regulating the mTOR/LC3II and Bax/Bcl-2 signalling pathways.

OBJECTIVES: Xanthohumol (XAN) is a unique component of Humulus lupulus L. and is known for its diverse biological activities. In this study, we investigated whether Xanthohumol could ameliorate memory impairment of APP/PS1 mice, and explored its potential mechanism of action. METHODS: APP/PS1 mice were used for in vivo test and were treated with N-acetylcysteine and Xanthohumol for 2 months. Learning and memory levels were evaluated by the Morris water maze. Inflammatory and oxidative markers in serum and hippocampus and the deposition of Aß in the hippocampus were determined. Moreover, the expression of autophagy and apoptosis proteins was also evaluated by western blot. KEY FINDINGS: Xanthohumol significantly reduced the latency and increased the residence time of mice in the target quadrant. Additionally, Xanthohumol increased superoxide dismutase level and reduced Interleukin-6 and Interleukin-1ß levels both in serum and hippocampus. Xanthohumol also significantly reduced Aß deposition in the hippocampus and activated autophagy and anti-apoptotic signals. CONCLUSIONS: Xanthohumol effectively ameliorates memory impairment of APP/PS1 mice by activating mTOR/LC3 and Bax/Bcl-2 signalling pathways, which provides new insight into the neuroprotective effects of Xanthohumol.

Pharmacokinetics of xanthohumol in rats of both sexes after oral and intravenous administration of pure xanthohumol and prenylflavonoid extract.

BACKGROUND: Female inflorescences of hops (Humulus lupulus L.) are wildly used in the brewing industry. Hops have been also used for ages in folk medicine. Xanthohumol (XN) is a most abundant prenylated flavonoid present in hops. OBJECTIVES: To determine pharmacokinetic parameters and bioavailability of pure XN and XN given in prenylflavonoid extract obtained from spent hops (HOP). MATERIAL AND METHODS: Fifty-six Wistar rats (28 females and 28 males) were administered with XN or HOP. Xanthohumol was administered either intravenously (iv.) (10 mg/kg) or orally (per os (p.o.)) (40, 100 and 200 mg/kg). Extract obtained from spent hops was administered p.o. and its doses were based on XN content (doses were equivalent to XN dose of 40, 100 and 200 mg/kg, respectively). After administration of XN or HOP serum, XN concentration was measured at different time points (0, 0.25, 0.5, 1, 2, 4, 6, 12, 24, 48, 72, and 96 h). Non-compartmental analysis was used to assess the pharmacokinetics (PK) of XN in rats. RESULTS: The XN PK in rats after intravenous administration is characterized by extensive distribution followed by delayed elimination from the body. Enterohepatic recirculation is likely to play a role in XN PK. Some fraction of the orally administered XN reaches central compartment rapidly; however, the overall absorption is very limited and probably saturable. The formulation-dependent factors also play an important role in the bioavailability of the drug. Although the CMAX concentration was higher in female rats receiving XN orally comparing to males, the other pharmacokinetic parameters were unaffected by the rats' sex. CONCLUSIONS: The same doses of XN may be administered to male and female subjects, as its pharmacokinetics is not affected by sex.

Curative effect of xanthohumol supplementation during liver fluke-associated cholangiocarcinogenesis: Potential involvement of autophagy.

Xanthohumol (XH), a plant flavonoid, was shown to attenuate cholangiocarcinoma (CCA) development induced by the liver fluke Opisthorchis viverrini (Ov) and N-dinitrosomethylamine (NDMA) in the hamster model. We investigated the possible involvement of autophagy, a self-degrading process dysregulated in cancer, in XH chemotherapeutic effect. During cholangiocarcinogenesis, the expression of LC3 (an autophagic marker) was increased in the precancerous stage and decreased in the cancerous stage. The XH-treated ON (Ov plus NDMA) group showed retarded progression of CCA along with increased expression of LC3. The possible relation between autophagy and cell death was investigated in cultured human CCA cells. XH induced apoptosis associated with reduced expression of BCL-2 and increased expression of BAX. In parallel, XH induced the autophagy flux, as testified by increased LC3-II and decreased p62, along with induction of BECLIN1 and Vps34. Inhibition of BECLIN1-dependent autophagy greatly limited XH toxicity in CCA cells. These data suggest that XH attenuates the development of CCA through overstimulation of autophagy which then precipitates apoptosis.

Micellar solubilization enhances the anti-inflammatory effect of xanthohumol.

BACKGROUND: Xanthohumol is known to exert anti-inflammatory properties but has poor oral bioavailability. Using advanced micellization technology, it has been possible to markedly enhance its bioavailability. PURPOSE: In the present study, we compared the chronic anti-inflammatory activities of native and micellar xanthohumol in the rat adjuvant arthritis model, using diclofenac as a reference drug. METHODS: Adjuvant arthritis was induced by injecting Freund's complete adjuvant into the right hind paw of rats and monitoring paw volume over 3 weeks. The drugs were given daily for 3 weeks, starting from the day of adjuvant inoculation. Serum was collected at the end of the experiment to measure inflammatory and oxidative stress parameters. Statistical comparisons between different groups were carried out by one-way analysis of variance followed by Tukey-Kramer multiple comparison test. RESULTS: Micellar solubilized xanthohumol showed a better anti-inflammatory activity than its native form. The reduction in paw volume was reflected in corresponding changes in relevant mediators of inflammation like tumor necrosis factor-α, interleukin-6 and C-reactive protein, myloperoxidase and lipid peroxidation markers. CONCLUSION: The findings confirm that micellar solubilization of xanthohumol enhances its anti-inflammatory activity, probably as a result of improving its bioavailabilty. The solubilized xanthohumol may prove to be a promising adjuvant tool for anti-inflammatory treatment and a potential anti-inflammatory alternative to synthetic drugs.

Determination of Xanthohumol in Hops, Food Supplements and Beers by HPLC.

Xanthohumol (XN) is the main prenylated chalcone present in hops (Humulus lupulus) with high biological activity, and it is of great importance for human health because of its antioxidant, anti-inflammatory, immunosuppressive and chemopreventive properties. This polyphenol can be included in the diet through foods in which hops are used, such as beer or food supplements. Because of their health benefits and the increasing interest of using hops as a novel nutraceutical, the aim of this work was the identification and quantification of XN in different types of samples using a method based on high resolution liquid chromatography with a diode array detector (HPLC-DAD). The method was validated in terms of linearity, limits of detection (LOD) and quantification (LOQ), repeatability and recovery. Acceptable linearity (r2 0.9999), adequate recovery (>90% in the most of cases) and good sensitivity (LOD 16 µg/L) were obtained. Furthermore, the presence of XN in all samples was confirmed using liquid chromatography coupled to mass spectrometry (LC-MS/MS) operated in negative ESI (electrospray system ionization) mode. The concentrations of XN determined in hop flowers and food supplements were above the LOQ, in a range between 0.106 and 12.7 mg/g. Beer may also represent an important source of dietary prenylflavonoids, with between 0.028 and 0.062 mg/L of XN. The results showed that the methodology proposed was suitable for the determination of XN in the different types of samples studied, and the amounts of XN varied significantly according to the selected product.