Xanthohumol, a chalcon derived from hops, inhibits hepatic inflammation and fibrosis

Pharmacology of bioactive compounds from plant extracts for improving non-alcoholic fatty liver disease through endoplasmic reticulum stress modulation: A comprehensive review

Background

Non-alcoholic fatty liver disease (NAFLD) is a prevalent chronic liver condition with significant clinical implications. Emerging research indicates endoplasmic reticulum (ER) stress as a critical pathogenic factor governing inflammatory responses, lipid metabolism and insulin signal transduction in patients with NAFLD. ER stress-associated activation of multiple signal transduction pathways, including the unfolded protein response, disrupts lipid homeostasis and substantially contributes to NAFLD development and progression. Targeting ER stress for liver function enhancement presents an innovative therapeutic strategy. Notably, the natural bioactive compounds of plant extracts have shown potential for treating NAFLD by reducing the level of ER stress marker proteins and mitigating inflammation, stress responses, and de novo lipogenesis. However, owing to limited comprehensive reviews, the effectiveness and pharmacology of these bioactive compounds remain uncertain.

Objectives

To address the abovementioned challenges, the current review categorizes the bioactive compounds of plant extracts by chemical structures and properties into flavonoids, phenols, terpenoids, glycosides, lipids and quinones and examines their ameliorative potential for NAFLD under ER stress.

Methods

This review systematically analyses the literature on the interactions of bioactive compounds from plant extracts with molecular targets under ER stress, providing a holistic view of NAFLD therapy.

Results

Bioactive compounds from plant extracts may improve NAFLD by alleviating ER stress; reducing lipid synthesis, inflammation, oxidative stress and apoptosis and enhancing fatty acid metabolism. This provides a multifaceted approach for treating NAFLD.

Conclusion

This review underscores the role of ER stress in NAFLD and the potential of plant bioactive compounds in treating this condition. The molecular mechanisms by which plant bioactive compounds interact with their ER stress targets provide a basis for further exploration in NAFLD management.

Xanthohumol, a prenylated flavonoid from hops (Humulus lupulus L.) exerts multidirectional pro-healing properties towards damaged zebrafish hair cells by regulating the innate immune response

Xanthohumol (XN) is a prominent prenylated flavonoid present in the hop plant (Humulus lupulus L.). Despite undoubted pro-healing properties of hop plant, there is still a need for clinical investigations confirming these effects as well as the underlying molecular mechanisms. The present study was designed to (1) establish the role of XN in non-invasive inflammation induced by chemical damage to zebrafish hair cells, (2) clarify if it influences cell injury severity, neutrophil migration, macrophage activation, cell regeneration, and (3) find out whether it modulates the gene expression profile of chosen immune and stress response markers. All experiments were performed on 3 dpf zebrafish larvae. After fertilization the embryos were transferred to appropriate XN solutions (0.1 μM, 0.3 μM and 0.5 μM). The 40 min 10 μM CuSO4 exposure evoked severe damage to posterior lateral line hair cells triggering a robust acute inflammatory response. Four readouts were selected as the indicators of XN role in the process of inflammation: 1) hair cell death, 2) neutrophil migration towards damaged hair cells, 3) macrophage activation and recruitment to damaged hair cells, 4) hair cell regeneration. The assessments involved in vivo confocal microscopy imaging and qPCR based molecular analysis. It was demonstrated that XN (1) influences death pathway of damaged hair cells by redirecting their severe necrotic phenotype into apoptotic one, (2) impacts the immune response via regulating neutrophil migration, macrophage recruitment and activation (3) modulates gene expression of immune system markers and (4) accelerates hair cell regeneration.

Research Progress Regarding the Effect and Mechanism of Dietary Polyphenols in Liver Fibrosis

The development of liver fibrosis is a result of chronic liver injuries may progress to liver cirrhosis and liver cancer. In recent years, liver fibrosis has become a major global problem, and the incidence rate and mortality are increasing year by year. However, there are currently no approved treatments. Research on anti-liver-fibrosis drugs is a top priority. Dietary polyphenols, such as plant secondary metabolites, have remarkable abilities to reduce lipid metabolism, insulin resistance and inflammation, and are attracting more and more attention as potential drugs for the treatment of liver diseases. Gradually, dietary polyphenols are becoming the focus for providing an improvement in the treatment of liver fibrosis. The impact of dietary polyphenols on the composition of intestinal microbiota and the subsequent production of intestinal microbial metabolites has been observed to indirectly modulate signaling pathways in the liver, thereby exerting regulatory effects on liver disease. In conclusion, there is evidence that dietary polyphenols can be therapeutically useful in preventing and treating liver fibrosis, and we highlight new perspectives and key questions for future drug development.

Xanthohumol attenuates renal ischemia/reperfusion injury by inhibiting ferroptosis

Ischemia/reperfusion injury (IRI) is a notable contributor to kidney injury, but effective prevention and treatment options are limited. The present study aimed to evaluate the impact of xanthohumol (XN), a kind of flavonoid, on renal IRI and its pathological process in rats. Rats and HK-2 cells were divided into five groups: Sham (control), IR [hypoxia-reoxygenation (HR)], IR (HR) + XN, IR (HR) + erastin or IR (HR) + XN + erastin. The effects of XN and erastin (a ferroptosis inducer) on IRI in rats were evaluated using blood urea nitrogen, plasma creatinine, glutathione, superoxide dismutase and malondialdehyde kits, western blotting, cell viability assay, hematoxylin and eosin staining and reactive oxygen species (ROS) detection. Nrf2 small interfering (si)RNA was used to investigate the role of the Nrf2/heme oxygenase (HO)-1 axis in XN-mediated protection against HR injury. Cell viability, ROS levels and expression of ferroptosis-related proteins were analyzed. Following IR, renal function of rats was severely impaired and oxidative stress and ferroptosis levels significantly increased. However, XN treatment decreased renal injury and inhibited oxidative stress and ferroptosis in renal tubular epithelial cells. Additionally, XN upregulated the Nrf2/HO-1 signaling pathway and Nrf2-siRNA reversed the renoprotective effect of XN. XN effectively decreased renal IRI by inhibiting ferroptosis and oxidative stress and its protective mechanism may be associated with the Nrf2/HO-1 signaling pathway.

The Hepatic Antisteatosis Effect of Xanthohumol in High-Fat Diet-Fed Rats Entails Activation of AMPK as a Possible Protective Mechanism

Obesity is the leading cause of non-alcoholic fatty liver disease by provoking hyperglycemia, hyperlipidemia, insulin resistance, oxidative stress, and inflammation. Low activity of AMP-activated protein kinase (AMPK) is linked to obesity, liver injury, and NAFLD. This study involves examining if the anti-steatosis effect of Xanthohumol (XH) in high-fat diet (HFD)-fed rats involves the regulation of AMPK. Adult male rats were divided into five groups (n = 8 each) as control (3.85 kcal/g); XH (control diet + 20 mg/kg), HFD (4.73 kcl/g), HFD + XH (20 mg/kg), and HFD + XH (30 mg/kg) + compound c (cc) (0.2 mg/kg). All treatments were conducted for 12 weeks. Treatment with XH attenuated the gain in body weight, fat pads, fasting glucose, and insulin in HFD rats. It also lowered serum leptin and free fatty acids (FFAs) and improved glucose and insulin tolerances in these rats. It also attenuated the increase in serum livers of liver marker enzymes and reduced serum and hepatic levels of triglycerides (TGs), cholesterol (CHOL), FFAs, as well as serum levels of low-density lipoproteins cholesterol (LDL-c) oxidized LDL-c. XH also reduced hepatic levels of malondialdehyde (MDA), nuclear accumulation of NF-κB, and the levels of tumor necrosis-factor-α (TNF-α) and interleukin-6 (IL-6) while stimulating the nuclear levels of Nrf2 and total levels of glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) in these HFD-fed rats. At the molecular levels, XH increased hepatic mRNA expression and phosphorylation of AMPK (Thr72) and reduced the expression of lipogenic genes SREBP1c and ACC-1. In concomitance, XH reduced hepatic liver droplet accumulation, reduced the number of apoptotic nuclei, and improved the structures of nuclei, mitochondria, and rough endoplasmic reticulum. Co-treatment with CC, an AMPK inhibitor, completely abolished all these effects of XH. In conclusion, XH attenuates obesity and HFD-mediated hepatic steatosis by activating hepatic AMPK.

A comprehensive review of the benefits of drinking craft beer: Role of phenolic content in health and possible potential of the alcoholic fraction

Currently, there is greater production and consumption of craft beer due to its appreciated sensory characteristics. Unlike conventional beer, craft beers provide better health benefits due to their varied and high content of phenolic compounds (PCs) and also due to their alcohol content, but the latter is controversial. The purpose of this paper was to report on the alcoholic fraction and PCs present in craft beers and their influence on health. Despite the craft beer boom, there are few studies on the topic; there is a lot of field to explore. The countries with the most research are the United States > Italy > Brazil > United Kingdom > Spain. The type and amount of PCs in craft beers depends on the ingredients and strains used, as well as the brewing process. It was determined that it is healthier to be a moderate consumer of alcohol than to be a teetotaler or heavy drinker. Thus, studies in vitro, with animal models and clinical trials on cardiovascular and neurodegenerative diseases, cancer, diabetes and obesity, osteoporosis and even the immune system suggest the consumption of craft beer. However, more studies with more robust designs are required to obtain more generalizable and conclusive results. Finally, some challenges in the production of craft beer were detailed and some alternative solutions were mentioned.

Xanthohumol-Enriched Beer Does Not Exert Antitumorigenic Effects on HeLa Cell Line In Vivo

Xanthohumol is a hop-derived flavonoid that has been widely examined for its health-protecting and antitumorigenic properties, but not yet in a natural beer matrix. The aim of the study was to investigate the antitumorigenic potential of a xanthohumol-enriched beer in vivo. Four groups of 4 × 10 nude mice were formed. Following the injection of HeLa tumorigenic cell lines, the treatment groups were administered a xanthohumol supplementation for 100 days, either dissolved in beer or in an ethanolic solution with the same alcohol strength as beer. The control groups received un-supplemented material. The terminal tumor masses, liver weights, and plasma antioxidant capacities (FRAP and ABTS methods) were measured. For the statistical analysis, a two-way ANOVA test was performed (p < 0.05). There were no statistically significant differences in tumor size between the groups. Xanthohumol did not induce higher levels of plasma antioxidant capacity, neither in beer nor in the water-ethanol matrix. The terminal liver weights were significantly higher in the control group receiving the unsupplemented ethanol solution. Xanthohumol dissolved in beer or in the water-alcohol matrix did not have a protective effect on tumor growth, nor did it have a positive effect on plasma antioxidant capacity either. However, beer with added xanthohumol had a less harmful effect on the liver compared to the supplemented water-ethanol solution. Our results indicate the possible negative countereffect of ethanol; however, further investigations are needed.

Xanthohumol Interferes with the Activation of TGF-β Signaling in the Process Leading to Intestinal Fibrosis

Fibrosis has various biological processes and affects almost every organ, especially in patients with inflammatory bowel disease, including Crohn's disease, who experience discomfort caused by intestinal fibrosis, which is a problem that needs to be resolved. TGF-β signaling is known to act as a key regulator of intestinal fibrosis, and its modulation could be an excellent candidate for fibrosis therapy. Xanthohumol (XN) has various effects, including anti-inflammation and anti-cancer; however, the detailed mechanism of TGF-β signaling has not yet been studied. The purpose of this study was to investigate the mechanism underlying the anti-fibrotic effect of XN on TGF-β1-induced intestinal fibrosis using primary human intestinal fibroblasts (HIFs). In this study, to check the anti-fibrotic effects of XN on intestinal fibrosis, we assessed the expression of fibrosis-related genes in TGF-β1-stimulated HIFs by qPCR, immunoblotting, and immunofluorescence staining. As a result, XN showed the ability to reduce the expression of fibrosis-associated genes increased by TGF-β1 treatment in HIFs and restored the cell shape altered by TGF-β1. In particular, XN repressed both NF-κB- and Smad-binding regions in the α-SMA promoter, which is important in fibrosis. In addition, XN inhibited NF-κB signaling, including phosphorylated-IkBα and cyclooxygenase-2 expression, and TNF-α-stimulated transcriptional activity of NF-κB. XN attenuated TGF-β1-induced phosphorylation of Smad2 and Smad3, and the transcriptional activity of CAGA. Particularly, XN interfered with the binding of TGF-Receptor I (TβRI) and Smad3 by binding to the kinase domain of the L45 loop of TβRI, thereby confirming that the fibrosis mechanism did not proceed further. In conclusion, XN has an inhibitory effect on TGF-β1-induced intestinal fibrosis in HIFs, significantly affecting TGF-β/Smad signaling.

A Xanthohumol-Rich Hop Extract Diminishes Endotoxin-Induced Activation of TLR4 Signaling in Human Peripheral Blood Mononuclear Cells: A Study in Healthy Women

Infections with Gram-negative bacteria are still among the leading causes of infection-related deaths. Several studies suggest that the chalcone xanthohumol (XN) found in hop (Humulus lupulus) possesses anti-inflammatory effects. In a single-blinded, placebo controlled randomized cross-over design study we assessed if the oral intake of a single low dose of 0.125 mg of a XN derived through a XN-rich hop extract (75% XN) affects lipopolysaccharide (LPS)-induced immune responses in peripheral blood mononuclear cells (PBMCs) ex vivo in normal weight healthy women (n = 9) (clinicaltrials.gov: NCT04847193) and determined associated molecular mechanisms. LPS-stimulation of PBMCs isolated from participants 1 h after the intake of the placebo for 2 h resulted in a significant induction of pro-inflammatory cytokine release which was significantly attenuated when participants had consumed XN. The XN-dependent attenuation of proinflammatory cytokine release was less pronounced 6 h after the LPS stimulation while the release of sCD14 was significantly reduced at this timepoint. The LPS-dependent activation of hTLR4 transfected HEK293 cells was significantly and dose-dependently suppressed by the XN-rich hop extract which was attenuated when cells were co-challenged with sCD14. Taken together, our results suggest even a one-time intake of low doses of XN consumed in a XN-rich hop extract can suppress LPS-dependent stimulation of PBMCs and that this is related to the interaction of the hop compound with the CD14/TLR4 signaling cascade.

Xanthohumol exerts anti-inflammatory effects in an in vitro model of mechanically stimulated cementoblasts

Xanthohumol (XN) is a prenylated plant polyphenol that naturally occurs in hops and its products, e.g. beer. It has shown to have anti-inflammatory and angiogenesis inhibiting effects and it prevents the proliferation of cancer cells. These effects could be in particular interesting for processes within the periodontal ligament, as previous studies have shown that orthodontic tooth movement is associated with a sterile inflammatory reaction. Based on this, the study evaluates the anti-inflammatory effect of XN in cementoblasts in an in vitro model of the early phase of orthodontic tooth movement by compressive stimulation. XN shows a concentration-dependent influence on cell viability. Low concentrations between 0.2 and 0.8 µM increase viability, while high concentrations between 4 and 8 µM cause a significant decrease in viability. Compressive force induces an upregulation of pro-inflammatory gene (Il-6, Cox2, Vegfa) and protein (IL-6) expression. XN significantly reduces compression related IL-6 protein and gene expression. Furthermore, the expression of phosphorylated ERK and AKT under compression was upregulated while XN re-established the expression to a level similar to control. Accordingly, we demonstrated a selective anti-inflammatory effect of XN in cementoblasts. Our findings provide the base for further examination of XN in modulation of inflammation during orthodontic therapy and treatment of periodontitis.

The importance of natural chalcones in ischemic organ damage: Comprehensive and bioinformatic analysis review

Over the last few decades, extensive research has been conducted, yielding a detailed account of thousands of newly discovered compounds of natural origin and their biological activities, all of which have the potential to be used for a wide range of therapeutic purposes. There are multiple research papers denoting the central objective of chalcones, which have been shown to have therapeutic potential against various forms of ischemia. The various aspects of chalcones are discussed in this review regarding molecular mechanisms involved in the promising anti-ischemic potential of these chalcones. The main mechanisms involved in these protective effects are Nrf2/Akt activation and NF-κB/TLR4 suppression. Furthermore, in-silico studies were carried out to discover the probable binding of these chalcones to Keap-1 (an inhibitor of Nrf2), Akt, NF-κB, and TLR4 protein molecules. Besides, network pharmacology analysis was conducted to predict the interacting partners of these signals. The obtained results indicated that Nrf2, Akt, NF-κB, and TLR4 are involved in the beneficial anti-ischemic actions of chalcones. Conclusively, the present findings show that chalcones as anti-ischemic agents have a valid rationale. The discussed studies will provide a comprehensive viewpoint on chalcones and can help to optimize their effects in different ischemia. PRACTICAL APPLICATIONS: Ischemic organ damage is an unavoidable pathological condition with a high worldwide incidence. According to the current research progress, natural chalcones have been proved to treat and/or prevent various types of ischemic organ damage by alleviating oxidative stress, inflammation, and apoptosis by different molecular mechanisms. This article displays the comprehensive research progress and the molecular basis of ischemic organ damage pathophysiology and introduces natural chalcones' mechanism in the ischemic organ condition.

Oral intake of xanthohumol attenuates lipoteichoic acid-induced inflammatory response in human PBMCs

PURPOSE

The aim of the study was to determine if xanthohumol, a prenylated chalcone found in Hop (Humulus lupulus), has anti-inflammatory effects in healthy humans if applied in low doses achievable through dietary intake.

METHODS

In a placebo-controlled single-blinded cross-over design study, 14 healthy young men and women either consumed a beverage containing 0.125 mg xanthohumol or a placebo. Peripheral blood mononuclear cells (PBMCs) were isolated before and 1 h after the intake of the beverages. Subsequently, PBMCs were stimulated with or without lipoteichoic acid (LTA) for 24 and 48 h. Concentrations of interleukin-1β (IL-1β), interleukin-6 (IL-6) and soluble cluster of differentiation (sCD14) protein were determined in cell culture supernatant. Furthermore, hTLR2 transfected HEK293 cells were stimulated with LTA in the presence or absence of xanthohumol and sCD14.

RESULTS

The stimulation of PBMCs with LTA for 24 and 48 h resulted in a significant induction of IL-1β, IL-6, and sCD14 protein release in PBMCs of both, fasted subjects and subjects after the ingestion of the placebo. In contrast, after ingesting xanthohumol, LTA-dependent induction of IL-1β, IL-6, and sCD14 protein release from PBMCs was not significantly higher than in unstimulated cells after 48 h. In hTLR2 transfected HEK293 cells xanthohumol significantly suppressed the LTA-dependent activation of cells, an effect attenuated when cells were co-incubated with sCD14.

CONCLUSION

The results of our study suggest that an ingestion of low doses of xanthohumol can suppress the LTA-dependent stimulation of PBMCs through mechanisms involving the interaction of CD14 with TLR2. Study registered at ClinicalTrials.gov (NCT04847193, 22.03.2022).

The Pathogenesis of HCC Driven by NASH and the Preventive and Therapeutic Effects of Natural Products

Nonalcoholic steatohepatitis (NASH) is a clinical syndrome with pathological changes that are similar to those of alcoholic hepatitis without a history of excessive alcohol consumption. It is a specific form of nonalcoholic fatty liver disease (NAFLD) that is characterized by hepatocyte inflammation based on hepatocellular steatosis. Further exacerbation of NASH can lead to cirrhosis, which may then progress to hepatocellular carcinoma (HCC). There is a lack of specific and effective treatments for NASH and NASH-driven HCC, and the mechanisms of the progression of NASH to HCC are unclear. Therefore, there is a need to understand the pathogenesis and progression of these diseases to identify new therapeutic approaches. Currently, an increasing number of studies are focusing on the utility of natural products in NASH, which is likely to be a promising prospect for NASH. This paper reviews the possible mechanisms of the pathogenesis and progression of NASH and NASH-derived HCC, as well as the potential therapeutic role of natural products in NASH and NASH-derived HCC.

Synthesis and Evaluation of Coumarin-Chalcone Derivatives as α-Glucosidase Inhibitors

Coumarin and chalcone, two important kinds of natural product skeletons, both exhibit α-glucosidase inhibitory activity. In this work, coumarin-chalcone derivatives 3 (a∼v) were synthesized, and their α-glucosidase inhibitory activity was screened. The results showed that all synthetic derivatives (IC50: 24.09 ± 2.36 to 125.26 ± 1.18 μM) presented better α-glucosidase inhibitory activity than the parent compounds 3-acetylcoumarin (IC50: 1.5 × 105 μM) and the positive control acarbose (IC50: 259.90 ± 1.06 μM). Among them, compound 3t displayed the highest α-glucosidase inhibitory activity (IC50: 24.09 ± 2.36 μM), which was approximately 10 times stronger than that of acarbose. The kinetic assay of 3t (KI = 18.82 μM, KIS = 59.99 μM) revealed that these compounds inhibited α-glucosidase in a mixed-type manner. Molecular docking was used to simulate the interaction between α-glucosidase and compound 3t.

Bone morphogenetic protein 13 in hepatic stellate cells and hepatic fibrosis

Hepatic fibrosis can be considered as a deregulated wound healing process in response to chronic liver injury. Bone morphogenetic protein 13 (BMP13) has been described to promote bone and tendon repair. In this study, we aimed to analyze the expression and function of BMP13 in hepatic fibrosis. We found increased BMP13 expression during the activation of hepatic stellate cells (HSCs), which is known as the key event of hepatic fibrosis. Fitting to this, BMP13 was elevated in murine models of hepatic fibrosis, and immunofluorescence staining showed colocalization of BMP13 and α-smooth muscle actin (α-SMA), a marker for activated HSC, in cirrhotic human liver tissue. BMP13 depletion in activated human HSC reduced the phosphorylation of smad1/5/9 and the expression of the transcription factor inhibitor of differentiation 1 (ID1), a known BMP target gene and profibrogenic factor. Furthermore, BMP13-depletion led to reduced proliferation and downregulation of collagen I α1 (COL1A1) and α-SMA, and, interestingly, also reduced phosphorylation of extracellular signal-regulated kinases (ERK). Conversely, stimulation with recombinant BMP13 induced the phosphorylation of smad1/5/9 and ERK, as well as the proliferation and the expression of ID1, COL1A1, and α-SMA in HSCs. These stimulatory effects were inhibited by dorsomorphin 1, a small-molecule inhibitor of the BMP-type I receptors activin receptor-like kinase-2 and -3, which are both expressed by HSC. In summary, these data indicate increased BMP13 expression in hepatic fibrosis as a profibrogenic factor. Thus, this soluble growth factor might have the potential as a new fibrosis marker and antifibrogenic therapeutic target in patients with chronic liver disease.

Bioavailability and Cardiometabolic Effects of Xanthohumol: Evidence from Animal and Human Studies

Xanthohumol is the main prenylflavonoid in hops and has been associated with a wide range of health benefits, due to its anti-inflammatory, anti-oxidative, and cancer-preventive properties. Increasing evidence suggests that xanthohumol positively affects biomarkers associated with metabolic syndrome and cardiovascular diseases (CVDs). This review summarizes the effects of xanthohumol supplementation on body weight, lipid and glucose metabolism, systemic inflammation, and redox status. In addition, it provides insights into the pharmacokinetics of xanthohumol intake. Animal studies show that xanthohumol exerts beneficial effects on body weight, lipid profile, glucose metabolism, and other biochemical parameters associated with metabolic syndrome and CVDs. Although in vitro studies are increasingly elucidating the responsible mechanisms, the overall in vivo results are currently inconsistent and quantitatively insufficient. Pharmacokinetic and safety studies confirm that intake of xanthohumol is safe and well tolerated in both animals and humans. However, little is known about the metabolism of xanthohumol in the human body, and even less about its effects on body weight and CVD risk factors. There is an urgent need for studies investigating whether the effects of xanthohumol on body weight and cardiometabolic parameters observed in animal studies are reproducible in humans, and what dosage, formulation, and intervention period are required. This article is protected by copyright. All rights reserved.

Xanthohumol alleviates T2DM-induced liver steatosis and fibrosis by mediating the NRF2/RAGE/NF-κB signaling pathway

Hyperglycemia-associated advanced glycation end products (AGEs) and the receptor for AGE (RAGE) contribute to nonalcoholic fatty liver disease (NAFLD). Xanthohumol (XH) exhibits protective activities against liver diseases. Aim: To investigate the effects of XH on Type II diabetes mellitus (T2DM)-induced liver steatosis and fibrosis. Methods: NAFLD rat models were duplicated. Biomolecular markers were detected. Quantitative real-time PCR (RT-PCR) and western blot were used to detect mRNA and protein expression. Immunofluorescence assays were employed to identify the subcellular locations. Results: XH significantly ameliorated hyperglycemia and hyperlipidemia in rats. XH attenuated the expression of RAGE and NF-κB signaling. XH significantly alleviated inflammation and oxidation by upregulating NRF2 expression. Knockdown of NRF2 blocked XH protection in hepatocytes. Conclusion: XH protected against T2DM-induced liver steatosis and fibrosis by mediating NRF2/AGE/RAGE/NF-κB signaling.

Tetrahydroxanthohumol, a xanthohumol derivative, attenuates high-fat diet-induced hepatic steatosis by antagonizing PPARγ

We previously reported xanthohumol (XN), and its synthetic derivative tetrahydro-XN (TXN), attenuates high-fat diet (HFD)-induced obesity and metabolic syndrome in C57Bl/6J mice. The objective of the current study was to determine the effect of XN and TXN on lipid accumulation in the liver. Non-supplemented mice were unable to adapt their caloric intake to 60% HFD, resulting in obesity and hepatic steatosis; however, TXN reduced weight gain and decreased hepatic steatosis. Liver transcriptomics indicated that TXN might antagonize lipogenic PPARγ actions in vivo. XN and TXN inhibited rosiglitazone-induced 3T3-L1 cell differentiation concomitant with decreased expression of lipogenesis-related genes. A peroxisome proliferator activated receptor gamma (PPARγ) competitive binding assay showed that XN and TXN bind to PPARγ with an IC50 similar to pioglitazone and 8-10 times stronger than oleate. Molecular docking simulations demonstrated that XN and TXN bind in the PPARγ ligand-binding domain pocket. Our findings are consistent with XN and TXN acting as antagonists of PPARγ.

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 protect cognitive performance in diabetic model rats by inhibiting protein kinase B/nuclear factor kappa-B pathway

Xanthohumol (XN, 2', 4', 4-trihydroxy-6'-methoxy-3'-prenylchalcone), a polyphenol chalcone from hops (Humulus lupulus), has received increasing attention due to its multiple pharmacologic activities. As an active component in beers, its presence has been suggested to be linked to the epidemiologic observation of the beneficial effect of regular beer drinking. But regarding cardiovascular and immunologic effects of polyphenols and ethanol, benefits of beer drinking in patients with diabetes were still in doubt. Diabetes was induced in male Sprague-Dawley rats by administering a high-fat diet and an intraperitoneal 30 mg/kg streptozotocin injection. The animals were treated orally with saline or XN at 50 mg/kg/d for 4 weeks. At the end of the treatment, hippocampus from different groups were collected for biochemical examination. In this study, we found XN inhibit phosphorylation of protein kinase B and nuclear factor kappa-B which was overactivated in diabetic rats, followed by decreased blood glucose and increased body weight. Additionally, XN treatment significantly increased freezing time in a fear memory test. In further research, we found XN increased synaptic plasticity and dendritic spine density, while decreased reactive oxygen species in hippocampus slices from diabetic rats. All these results indicate that XN might be a promising drug to treat diabetic encephalopathy.

Xanthohumol: A Metabolite with Promising Anti-Neoplastic Potential

The overwhelming globalburden of cancer has posed numerous challenges and opportunities for developing anti-cancer therapies. Phytochemicalshave emerged as promising synergistic compounds with potential anti-cancer effects to supplement chemo- and immune-therapeutic regimens. Anti cancer synergistic effects have been investigated in the interaction between phytocompounds derived from flavonoids such as quercetin, apigenin, kaempferol, hesperidin, emodin etc., and conventional drugs. Xanthohumol is one of the prenylatedphytoflavonoid that has demonstrated key anti-cancer activities in in vitro (anti proliferation of cancer cell lines) and in vivo(animal models of xenograft tumours)studies, and has been explored from different dimensions for targeting cancer subtypes. In the last decade, xanthohumol has been investigated how it induces the anti-cancer effects at cellular and molecular level.The different signalling cascades and targets of xanthohumolare summarized in thisreview.Overall, this reviewsummarizes the current advances made in the field of natural compounds with special reference to xanthohumol and its promising anti-cancer effectsto inhibit tumour progression.The present review hasalso touched upon the potential of xanthohumol transitioning into a lead candidate from nano-therapy viewpoint along with the challenges which need to be addressed for extensive pre-clinical and clinical anti-cancer studies.

Xanthohumol, a Prenylated Chalcone Derived from Hops, Inhibits Growth and Metastasis of Melanoma Cells

Melanoma is one of the most aggressive and lethal cancers worldwide. Despite recent progress in melanoma therapy, the prognosis for metastasized melanoma continues to be poor. Xanthohumol (XN), a prenylated chalcone derived from hop cones, is known to possess a broad spectrum of chemopreventive and anticancer activities. However, few studies have analyzed functional XN effects on melanoma cells and there have been no previous in vivo studies of its effects on metastasis. The aim of this study was to investigate the impact of XN on the tumorigenic and liver metastatic activity of melanoma cells. XN exhibited dose-dependent cytotoxic effects on human melanoma cell lines (Mel Ju; Mel Im) in vitro. Functional analysis in the subtoxic dose-range revealed that XN dose-dependently inhibited proliferation, colony formation, and migratory activity of melanoma cells. Subtoxic XN doses also induced markers of endoplasmic reticulum stress but inhibited the phosphorylation of the protumorigenic c-Jun N-terminal kinases (JNK). Furthermore, XN effects on hepatic metastasis were analyzed in a syngeneic murine model (splenic injection of murine B16 melanoma cells in C57/BL6 mice). Here, XN significantly reduced the formation of hepatic metastasis. Metastases formed in the liver of XN-treated mice revealed significantly larger areas of central necrosis and lower Ki67 expression scores compared to that of control mice. In conclusion, XN inhibits tumorigenicity of melanoma cells in vitro and significantly reduced hepatic metastasis of melanoma cells in mice. These data, in conjunction with an excellent safety profile that has been confirmed in previous studies, indicate XN as a promising novel agent for the treatment of hepatic (melanoma) metastasis.

Molting method alternative and detection of estrogen receptors by immunohistochemical methods on molted layers

Three experiments were designed to evaluate the effects of different molting methods on the growth performance, detection of estrogen receptors (ERs), and immunohistochemical properties of some tissues in pre-, during, and post-molting of layers. In experiment 1, 302 Hy-line W-36 were reared from 75 to 76 weeks. In experiment 2, a total of 252 Hy-line W-36 were randomly allocated to 7 groups, with 6 replications and 6 birds in each. Hens fed in the E and D groups reached 30% of loss weight sooner (P < 0.05). Egg production was also sooner stopped in the FW group than in other ones (P < 0.05). In experiment 3, after inducing molting, each group in experiment 2 was divided into 2 groups with and without Humulus lupulus (Hop). The E group feed intake was increased, as compared to groups F and C (P < 0.05). A significant increase in egg weight was found by applying Hop and molting methods (P < 0.05). Days for return to the initial egg production and 10% egg laying were significantly decreased in the birds fed by Hop in the E and D groups (P < 0.05). The W-D, N-D, W-E, and N-E groups sooner returned to 50% egg laying, in comparison to other treatments (P < 0.05). Plasma estrogen and ERs were decreased by the molting programs, as compared with pre-molting; however, Hop increased their post-molting. After the molting period, egg production and ERs were increased significantly, as compared with the pre-molting period. To conclude, the white button mushroom residual, through decreasing ERs, could be used successfully for forced molting, and Hop could lead to a good performance by increasing ERs in the second laying cycle.

Pathogenesis of NASH and Promising Natural Products

Nonalcoholic steatohepatitis (NASH) is a common clinical condition that can lead to advanced liver diseases. The mechanism of the diaease progression, which is lacking effective therapy, remains obsure. Therefore, there is a need to understand the pathogenic mechanisms responsible for disease development and progression in order to develop innovative therapies. To accomplish this goal, experimental animal models that recapitulate the human disease are necessary. Currently, an increasing number of studies have focused on natural constituents from medicinal plants which have been emerged as a new hope for NASH. This review summarized the pathogenesis of NASH, animal models commonly used, and the promising targets for therapeutics. We also reviewed the natural constituents as potential NASH therapeutic agents.

Xanthohumol Inhibits TGF-β1-Induced Cardiac Fibroblasts Activation via Mediating PTEN/Akt/mTOR Signaling Pathway

Background

Xanthohumol (Xn) is the most abundant prenylated flavonoid in Hops (Humulus lupulus L.), and exhibits a range of pharmacological activities. This study aimed to investigate the effect of Xn on TGF-β1-induced cardiac fibroblasts activation and elucidate the underlying mechanism.

Materials and Methods

The cellTiter 96^® AQueous one solution cell proliferation assay kit was adopted to determine the cell viability of cardiac fibroblasts, and the proliferation was detected through 5-ethynyl-2'-deoxyuridine (EdU) incorporation assay. The α-SMA protein expression was measured by using immunofluorescence and Western blotting. Western blotting was conducted to test the protein expressions of collagen I and III, PTEN, p-Akt, Akt, p-mTOR, mTOR, p-Smad3, Smad3 and GAPDH. The mRNA levels of α-SMA, collagen I and III were determined by quantitative real-time polymerase chain reaction (PCR).

Results

Xn inhibited the TGF-β1-induced proliferation, differentiation and collagen overproduction of cardiac fibroblasts. TGF-β1 induced the down-regulated PTEN expression, Akt and mTOR phosphorylation. These effects of TGF-β1 were suppressed by Xn, while blocking of PTEN reduced Xn-mediated inhibitory effect on cardiac fibroblasts activation induced by TGF-β1.

Conclusion

Xn inhibits TGF-β1-induced cardiac fibroblasts activation via mediating PTEN/Akt/mTOR signaling pathway.

Discovery and Development of Inflammatory Inhibitors from 2-Phenylchromonone (Flavone) Scaffolds

Flavonoids are compounds based on a 2-phenylchromonone scaffold. Flavonoids can be divided into flavonoids, flavonols, dihydroflavones, anthocyanins, chalcones and diflavones according to the oxidation degree of the central tricarbonyl chain, the connection position of B-ring (2-or 3-position), and whether the tricarbonyl chain forms a ring or not. There are a variety of biological activities about flavonoids, such as anti-inflammatory activity, anti-oxidation and anti-tumor activity, and the antiinflammatory activity is apparent. This paper reviews the anti-inflammatory activities and mechanisms of flavonoids and their derivatives reported in China and abroad from 2011 till date (2011-2020), in order to find a good drug scaffold for the study of anti-inflammatory activities.

Metabolic Impact of Flavonoids Consumption in Obesity: From Central to Peripheral

The prevention and treatment of obesity is primary based on the follow-up of a healthy lifestyle, which includes a healthy diet with an important presence of bioactive compounds such as polyphenols. For many years, the health benefits of polyphenols have been attributed to their anti-oxidant capacity as free radical scavengers. More recently it has been described that polyphenols activate other cell-signaling pathways that are not related to ROS production but rather involved in metabolic regulation. In this review, we have summarized the current knowledge in this field by focusing on the metabolic effects of flavonoids. Flavonoids are widely distributed in the plant kingdom where they are used for growing and defensing. They are structurally characterized by two benzene rings and a heterocyclic pyrone ring and based on the oxidation and saturation status of the heterocyclic ring flavonoids are grouped in seven different subclasses. The present work is focused on describing the molecular mechanisms underlying the metabolic impact of flavonoids in obesity and obesity-related diseases. We described the effects of each group of flavonoids in liver, white and brown adipose tissue and central nervous system and the metabolic and signaling pathways involved on them.

The Modulation of Phase II Drug-Metabolizing Enzymes in Proliferating and Differentiated CaCo-2 Cells by Hop-Derived Prenylflavonoids

Prenylflavonoids in the human organism exhibit various health-beneficial activities, although they may interfere with drugs via the modulation of the expression and/or activity of drug-metabolizing enzymes. As intestinal cells are exposed to the highest concentrations of prenylflavonoids, we decided to study the cytotoxicity and modulatory effects of the four main hop-derived prenylflavonoids on the activities and mRNA expression of the main drug-conjugating enzymes in human CaCo-2 cells. Proliferating CaCo-2 cells were used for these purposes as a model of colorectal cancer cells, and differentiated CaCo-2 cells were used as an enterocyte-like model. All the tested prenylflavonoids inhibited the CaCo-2 cells proliferation, with xanthohumol proving the most effective (IC₅₀ 8.5 µM). The prenylflavonoids modulated the activities and expressions of the studied enzymes to a greater extent in the differentiated, as opposed to the proliferating, CaCo-2 cells. In the differentiated cells, all the prenylflavonoids caused a marked increase in glutathione S-transferase and catechol-O-methyltransferase activities, while the activity of sulfotransferase was significantly inhibited. Moreover, the prenylflavonoids upregulated the mRNA expression of uridine diphosphate (UDP)-glucuronosyl transferase 1A6 and downregulated that of glutathione S-transferase 1A1/2.

Hop bioactive compounds in prevention of nutrition-related noncommunicable diseases

Nutrition-related noncommunicable diseases (NR-NCDs) such as cardiovascular disease and type 2 diabetes both negatively impact the quality of life of many individuals and generate a substantial burden on society, demonstrating a need for intervention. Phytochemicals are investigated as a potential approach for combating NR-NCDs, and those found in hops have gained increased attention in recent decades. Hops, the strobile of the plant Humulus lupulus, are grown primarily for the brewing industry as they confer taste and increased shelf-life. The bitter acids represent the main compounds of interest for improving beer quality. Additionally, bitter acids as well as the prenylated chalcone xanthohumol, exhibit a wide range of health beneficial properties. This review summarizes those beneficial effects of bitter acids and xanthohumol on NR-NCDs, including inflammatory and immune diseases, obesity and metabolic disorders, as well as cancer prevention.

The Effect of Hops (Humulus lupulus L.) Extract Supplementation on Weight Gain, Adiposity and Intestinal Function in Ovariectomized Mice

Estrogen decline during menopause is associated with altered metabolism, weight gain and increased risk of cardiometabolic diseases. The gut microbiota also plays a role in the development of cardiometabolic dysfunction and is also subject to changes associated with age-related hormone changes. Phytoestrogens are plant-based estrogen mimics that have gained popularity as dietary supplements for the treatment or prevention of menopause-related symptoms. These compounds have the potential to both modulate and be metabolized by the gut microbiota. Hops (Humulus lupulus L.) contain potent phytoestrogen precursors, which rely on microbial biotransformation in the gut to estrogenic forms. We supplemented ovariectomized (OVX) or sham-operated (SHAM) C57BL/6 mice, with oral estradiol (E2), a flavonoid-rich extract from hops, or a placebo carrier oil, to observe effects on adiposity, inflammation, and gut bacteria composition. Hops extract (HE) and E2 protected against increased visceral adiposity and liver triglyceride accumulation in OVX animals. Surprisingly, we found no evidence of OVX having a significant impact on the overall gut bacterial community structure. We did find differences in the abundance of Akkermansia muciniphila, which was lower with HE treatment in the SHAM group relative to OVX E2 treatment and to placebo in the SHAM group.

Beneficial and Deleterious Effects of Female Sex Hormones, Oral Contraceptives, and Phytoestrogens by Immunomodulation on the Liver

The liver is considered the laboratory of the human body because of its many metabolic processes. It accomplishes diverse activities as a mixed gland and is in continuous cross-talk with the endocrine system. Not only do hormones from the gastrointestinal tract that participate in digestion regulate the liver functions, but the sex hormones also exert a strong influence on this sexually dimorphic organ, via their receptors expressed in liver, in both health and disease. Besides, the liver modifies the actions of sex hormones through their metabolism and transport proteins. Given the anatomical position and physiological importance of liver, this organ is evidenced as an immune vigilante that mediates the systemic immune response, and, in turn, the immune system regulates the hepatic functions. Such feedback is performed by cytokines. Pro-inflammatory and anti-inflammatory cytokines are strongly involved in hepatic homeostasis and in pathological states; indeed, female sex hormones, oral contraceptives, and phytoestrogens have immunomodulatory effects in the liver and the whole organism. To analyze the complex and interesting beneficial or deleterious effects of these drugs by their immunomodulatory actions in the liver can provide the basis for either their pharmacological use in therapeutic treatments or to avoid their intake in some diseases.

Therapeutic Application of Micellar Solubilized Xanthohumol in a Western-Type Diet-Induced Mouse Model of Obesity, Diabetes and Non-Alcoholic Fatty Liver Disease

Xanthohumol (XN), a prenylated chalcone from hops, has been reported to exhibit a variety of health-beneficial effects. However, poor bioavailability may limit its application in the prevention and therapy of diseases. The objective of this study was to determine whether a micellar solubilization of xanthohumol could enhance the bioavailability and biological efficacy of xanthohumol in a Western-type diet (WTD) induced model of obesity, diabetes and non-alcoholic fatty liver disease (NAFLD). After 3 weeks feeding with WTD, XN was additionally applied per oral gavage as micellar solubilizate (s-XN) or native extract (n-XN) at a daily dose of 2.5 mg/kg body weight for a further 8 weeks. Control mice received vehicle only in addition to the WTD. WTD-induced body weight-gain and glucose intolerance were significantly inhibited by s-XN application. Furthermore, WTD-induced hepatic steatosis, pro-inflammatory gene expression (MCP-1 and CXCL1) and immune cell infiltration as well as activation of hepatic stellate cells (HSC) and expression of collagen alpha I were significantly reduced in the livers of s-XN-treated mice compared to WTD controls. In contrast, application of n-XN had no or only slight effects on the WTD-induced pathological effects. In line with this, plasma XN concentration ranged between 100–330 nmol/L in the s-XN group while XN was not detectable in the serum samples of n-XN-treated mice. In conclusion, micellar solubilization enhanced the bioavailability and beneficial effects of xanthohumol on different components of the metabolic syndrome including all pathological steps of NAFLD. Notably, this was achieved in a dose more than 10-fold lower than effective beneficial doses of native xanthohumol reported in previous in vivo studies.

Moderate consumption of fermented alcoholic beverages diminishes diet-induced non-alcoholic fatty liver disease through mechanisms involving hepatic adiponectin signaling in mice

PURPOSE

Results of some epidemiological studies suggest that moderate alcohol consumption may be associated with a decreased risk to develop NAFLD. Here, the effect of the consumption of moderate beer and diluted ethanol, respectively, on the development of NAFLD were assessed.

METHODS

Female C57BL/6J mice were fed a control diet (C-D) or a diet rich in fructose, fat and cholesterol (FFC) enriched isocalorically and isoalcoholically with beer (FFC + B) or plain ethanol (FFC + E) (2.5 g ethanol/kg body weight/day) for 7 weeks. Liver damage was assessed by histology using NAFLD activity score. Markers of inflammation, insulin resistance and adiponectin signaling were measured at mRNA and protein levels. Using J774A.1 cells as a model of Kupffer cells, the effect of alcoholic beverages on adiponectin receptor 1 (Adipor1) was assessed.

RESULTS

Hepatic triglyceride concentration, neutrophil granulocytes, iNOS protein concentrations and early signs of insulin resistance found in FFC-fed mice were significantly attenuated in FFC+ B-fed mice (P < 0.05 for all). These findings were associated with a super-induction of Adipor1 mRNA expression (+ ~ 18-fold compared to all other groups) and a decrease of markers of lipid peroxidation in liver tissue of FFC + B-fed mice when compared to FFC-fed animals. Similar differences were not found between FFC- and FFC+ E-fed mice. Expression of Adipor1 was also super-induced (7.5-fold) in J774A.1 cells treated with beer (equivalent to 2 mmol/L ethanol).

CONCLUSIONS

These data suggest that moderate intake of fermented alcoholic beverages such as beer at least partially attenuates NAFLD development through mechanisms associated with hepatic AdipoR1 expression.

Potential Role of Flavonoids in Treating Chronic Inflammatory Diseases with a Special Focus on the Anti-Inflammatory Activity of Apigenin

Inflammation has been reported to be intimately linked to the development or worsening of several non-infectious diseases. A number of chronic conditions such as cancer, diabetes, cardiovascular disorders, autoimmune diseases, and neurodegenerative disorders emerge as a result of tissue injury and genomic changes induced by constant low-grade inflammation in and around the affected tissue or organ. The existing therapies for most of these chronic conditions sometimes leave more debilitating effects than the disease itself, warranting the advent of safer, less toxic, and more cost-effective therapeutic alternatives for the patients. For centuries, flavonoids and their preparations have been used to treat various human illnesses, and their continual use has persevered throughout the ages. This review focuses on the anti-inflammatory actions of flavonoids against chronic illnesses such as cancer, diabetes, cardiovascular diseases, and neuroinflammation with a special focus on apigenin, a relatively less toxic and non-mutagenic flavonoid with remarkable pharmacodynamics. Additionally, inflammation in the central nervous system (CNS) due to diseases such as multiple sclerosis (MS) gives ready access to circulating lymphocytes, monocytes/macrophages, and dendritic cells (DCs), causing edema, further inflammation, and demyelination. As the dearth of safe anti-inflammatory therapies is dire in the case of CNS-related disorders, we reviewed the neuroprotective actions of apigenin and other flavonoids. Existing epidemiological and pre-clinical studies present considerable evidence in favor of developing apigenin as a natural alternative therapy against chronic inflammatory conditions.

Protective effects of selenium-glutathione-enriched probiotics on CCl4-induced liver fibrosis

Hepatic fibrosis is a common pathological basis of liver cirrhosis and hepatocellular carcinomas. So, prevention and treatment of liver fibrosis is one of the crucial therapeutic goals in hepatology. Organic selenium, glutathione or probiotics supplementation could ameliorate hepatic fibrosis, respectively. The purpose of this study is to develop a novel selenium-glutathione-enriched probiotics (SGP) and to investigate its protective effect on CCl₄-induced liver fibrosis in rats. Yeast strains with the high-yield glutathione were isolated and identified by analysis of 26S ribosomal DNA sequences. The fermentation parameters of SGP were optimized through single-factor, Plackett-Burman (PB) design and response surface methodology (RSM). The final SGP contained 38.4 μg/g of organic selenium, 34.1 mg/g of intracellular glutathione, approximately 1×10¹⁰ CFU/g live Saccharomyces cerevisiae and 1×10¹² CFU/g live Lactobacillus acidophilus. SGP had better protective effects on liver fibrosis than selenium, glutathione or probiotics, respectively. The hepatic silent information regulator 1 (SIRT1) level was down-regulated and oxidative stress, endoplasmic reticulum (ER) stress, inflammation and phosphorylated MAPK was increased in CCl₄-treated rats. However, SGP can significantly reverse these changes caused by CCl₄. Our findings suggest that SGP was effective in attenuating liver fibrosis by the activation of SIRT1 signaling and attenuating hepatic oxidative stress, ER stress, inflammation and MAPK signaling.

Rice Protein Matrix Enhances Circulating Levels of Xanthohumol Following Acute Oral Intake of Spent Hops in Humans

SCOPE

Xanthohumol (XN), a prenylated flavonoid found in hops, exhibits anti-inflammatory and antioxidant properties. However, poor bioavailability may limit therapeutic applications. As food components are known to modulate polyphenol absorption, the objective is to determine whether a protein matrix could enhance the bioavailability of XN post oral consumption in humans.

METHODS AND RESULTS

This is a randomized, double-blind, crossover study in healthy participants (n = 6) evaluating XN and its major metabolites (isoxanthohumol [IX], 6- and 8-prenylnaringenin [6-PN, 8-PN]) for 6 h following consumption of 12.4 mg of XN delivered via a spent hops-rice protein matrix preparation or a control spent hops preparation. Plasma XN and metabolites are measured by LC-MS/MS. C_max , T_max , and area-under-the-curve (AUC) values were determined. Circulating XN and metabolite response to each treatment was not bioequivalent. Plasma concentrations of XN and XN + metabolites (AUC) are greater with consumption of the spent hops-rice protein matrix preparation.

CONCLUSION

Compared to a standard spent hops powder, a protein-rich spent hops matrix demonstrates enhanced plasma levels of XN and metabolites following acute oral intake.

Protective effect of xanthohumol against age-related brain damage

It has been recently shown that xanthohumol, a flavonoid present in hops, possesses antioxidant, anti-inflammatory and chemopreventive properties. However, its role in the aging brain has not been addressed so far. Therefore, this study aimed to investigate the possible neuroprotective activity of xanthohumol against age-related inflammatory and apoptotic brain damage in male senescence-accelerated prone mice (SAMP8). Animals were divided into 4 groups: Untreated young mice, untreated old mice and old mice treated either with 1 mg kg^-1 day^-1 or 5 mg kg^-1 day^-1 xanthohumol. Young and old senescence accelerated resistant mice (SAMR1) were used as controls. After 30 days of treatment, animals were sacrificed and their brains were collected and immediately frozen in liquid nitrogen. mRNA (GFAP, TNF-α, IL-1β, AIF, BAD, BAX, XIAP, NAIP and Bcl-2) and protein (GFAP, TNF-α, IL-1β, AIF, BAD, BAX, BDNF, synaptophysin and synapsin) expressions were measured by RT-PCR and Western blotting, respectively. Significant increased levels of pro-inflammatory (TNF-α, IL-1β) and pro-apoptotic (AIF, BAD, BAX) markers were observed in both SAMP8 and SAMR1 old mice compared to young animals (P<.05) and also in SAMP8 untreated old mice compared to SAMR1 (P<.05). These alterations were significantly less evident in animals treated with both doses of xanthohumol (P<.05). Also, a reduced expression of synaptic markers was observed in old mice compared to young ones (P<.05) but it significantly recovered with 5 mg kg^-1 day^-1 xanthohumol treatment (P<.05). In conclusion, xanthohumol treatment modulated the inflammation and apoptosis of aged brains, exerting a protective effect on damage induced by aging.

Xanthohumol improves dysfunctional glucose and lipid metabolism in diet-induced obese C57BL/6J mice

Xanthohumol (XN) is a prenylated flavonoid found in hops (Humulus lupulus) and beer. The dose-dependent effects of XN on glucose and lipid metabolism in a preclinical model of metabolic syndrome were the focus of our study. Forty-eight male C57BL/6J mice, 9 weeks of age, were randomly divided into three XN dose groups of 16 animals. The mice were fed a high-fat diet (60% kcal as fat) supplemented with XN at dose levels of 0, 30, or 60 mg/kg body weight/day, for 12 weeks. Dietary XN caused a dose-dependent decrease in body weight gain. Plasma levels of glucose, total triglycerides, total cholesterol, and MCP-1 were significantly decreased in mice on the 60 mg/kg/day treatment regimen. Treatment with XN at 60 mg/kg/day resulted in reduced plasma LDL-cholesterol (LDL-C), IL-6, insulin and leptin levels by 80%, 78%, 42%, and 41%, respectively, compared to the vehicle control group. Proprotein Convertase Subtilisin Kexin 9 (PCSK-9) levels were 44% lower in the 60 mg/kg dose group compared to the vehicle control group (p ≤ 0.05) which may account for the LDL-C lowering activity of XN. Our results show that oral administration of XN improves markers of systemic inflammation and metabolic syndrome in diet-induced obese C57BL/6J mice.

Hepatoprotective and Anti-fibrotic Agents: It's Time to Take the Next Step

Hepatic fibrosis and cirrhosis cause strong human suffering and necessitate a monetary burden worldwide. Therefore, there is an urgent need for the development of therapies. Pre-clinical animal models are indispensable in the drug discovery and development of new anti-fibrotic compounds and are immensely valuable for understanding and proofing the mode of their proposed action. In fibrosis research, inbreed mice and rats are by far the most used species for testing drug efficacy. During the last decades, several hundred or even a thousand different drugs that reproducibly evolve beneficial effects on liver health in respective disease models were identified. However, there are only a few compounds (e.g., GR-MD-02, GM-CT-01) that were translated from bench to bedside. In contrast, the large number of drugs successfully tested in animal studies is repeatedly tested over and over engender findings with similar or identical outcome. This circumstance undermines the 3R (Replacement, Refinement, Reduction) principle of Russell and Burch that was introduced to minimize the suffering of laboratory animals. This ethical framework, however, represents the basis of the new animal welfare regulations in the member states of the European Union. Consequently, the legal authorities in the different countries are halted to foreclose testing of drugs in animals that were successfully tested before. This review provides a synopsis on anti-fibrotic compounds that were tested in classical rodent models. Their mode of action, potential sources and the observed beneficial effects on liver health are discussed. This review attempts to provide a reference compilation for all those involved in the testing of drugs or in the design of new clinical trials targeting hepatic fibrosis.

Chalcones from Angelica keiskei attenuate the inflammatory responses by suppressing nuclear translocation of NF-κB

The ethyl acetate-soluble fraction from the ethanolic extract of Angelica keiskei showed potent inhibitory activity against the production of nitric oxide (NO) in lipopolysaccharide (LPS)-activated RAW 264.7 cells. We identified seven chalcones (1-7) from EtOAc-soluble fractions through the activity-guided separation. Four active principles, identified as 4-hydroxyderrcine (1), xanthoangelol E (2), xanthokeismin A (4), and xanthoangelol B (5), inhibited the production of NO and the expression of proinflammatory cytokines, interleukin (IL)-1β and IL-6, in LPS-activated macrophages. Western blotting and reverse transcription-polymerase chain reaction analysis demonstrated that these chalcones attenuated protein and mRNA levels of inflammatory enzymes such as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Moreover, these active compounds suppressed the degradation of inhibitory-κBα (I-κBα) and the translocation of nuclear factor κB (NF-κB) into nuclei of LPS-activated macrophages. These data demonstrate that four chalcones (1, 2, 4, and 5) from A. keiskei can suppress the LPS-induced production of NO and the expression of iNOS/COX-2 genes by inhibiting the degradation of I-κBα and nuclear translocation of NF-κB. Taken together, four chalcones from A. keiskei may have efficacy as anti-inflammatory agents.

The hop constituent xanthohumol exhibits hepatoprotective effects and inhibits the activation of hepatic stellate cells at different levels

Xanthohumol is the principal prenylated flavonoid of the female inflorescences of the hop plant. In recent years, various beneficial xanthohumol effects including anti-inflammatory, antioxidant, hypoglycemic activities, and anticancer effects have been revealed. This review summarizes present studies indicating that xanthohumol also inhibits several critical pathophysiological steps during the development and course of chronic liver disease, including the activation and pro-fibrogenic genotype of hepatic stellate cells. Also the various mechanism of action and molecular targets of the beneficial xanthohumol effects will be described. Furthermore, the potential use of xanthohumol or a xanthohumol-enriched hop extract as therapeutic agent to combat the progression of chronic liver disease will be discussed. It is notable that in addition to its hepatoprotective effects, xanthohumol also holds promise as a therapeutic agent for treating obesity, dysregulation of glucose metabolism and other components of the metabolic syndrome including hepatic steatosis. Thus, therapeutic xanthohumol application appears as a promising strategy, particularly in obese patients, to inhibit the development as well as the progression of non-alcoholic fatty liver disease.