A systematic review on hepatoprotective activity of quercetin against various drugs and toxic agents: Evidence from preclinical studies

New Insights into Quercetin Restoring the Impairment of Testicular Angiogenesis Induced by Silicon Dioxide Particles in Food: Inhibiting ROS/PPARγ-Mediated Ferroptosis

Silicon dioxide particles (SiO2) have been widely used in food additives. Increasing data demonstrate that SiO2 can cause multisystem damage through oxidative stress. Quercetin (Que) is one of the most popular nutritional antioxidants. Ferroptosis reduces the level of angiogenesis. However, whether Que alleviates the inhibition of testicular angiogenesis by relieving SiO2-induced ferroptosis via ROS/PPARγ is unclear. Based on this, we established SiO2-exposed mice testicular and C166 cell models and added oxidative stress activators Sanguinarine chloride (SAN), PPARγ inhibitor GW9662, and ferroptosis activator Erastin to the models in vitro. The results showed that the SiO2 exposure group had antioxidant dysfunction; PPARγ was significantly downregulated; ferroptosis levels were increased; and angiogenesis was reduced. Que treatment can alleviate these changes. The addition of SAN, GW9662, and Erastin reduced the effects of Que by activating oxidative stress, inhibiting PPARγ, and activating ferroptosis, respectively. In general, Que can alleviate SiO2-induced ferroptosis through ROS/PPARγ, thus restoring testicular angiogenesis in mice.

Unveiling the hepatoprotective mechanisms of Desmodium heterocarpon (L.) DC: Novel flavonoid identification and Keap1/Nrf2 pathway activation

BACKGROUND

The pathophysiology of liver diseases is significantly influenced by oxidative stress, making its alleviation a key strategy for treatment. The Keap1/Nrf2 signaling pathway is the body's most crucial antioxidant defense mechanism. Traditional Chinese medicine, Desmodium heterocarpon (L.) DC, has shown promising hepatoprotective effects, however, the specific active components and underlying mechanisms of its liver-protective properties remain inadequately understood. Further investigation into the bioactive constituents and mechanisms of its hepatoprotective action is therefore essential.

OBJECTIVE

This study aims to identify the active ingredients in D. heterocarpon and to explore its hepatoprotective properties and underlying mechanisms.

METHODS

The hepatoprotective activity of the ethyl acetate fraction (JEAE) from D. heterocarpon was first evaluated utilizing a mouse model of acute liver damage (ALI) caused by CCl4. Molecular and histological analyses, including H&E staining, ELISA, and Western blot, were used to assess liver protection. The chemical constituents of JEAE were further identified using UPLC-MS/MS, and the molecular network of the JEAE fraction was analyzed. Compounds were isolated through column chromatography, and their antioxidant and hepatoprotective effects were assessed in an H₂O₂-induced HepG2 cell model using molecular assays. Additionally, binding interactions between active compounds and Keap1 were evaluated using molecular docking, molecular dynamics simulations, and surface plasmon resonance.

RESULTS

The ethyl acetate fraction of Desmodium heterocarpon (JEAE) showed remarkable antioxidant activity, with the highest flavonoid contents among extract fractions. In CCl₄-induced liver injury models, JEAE improved liver function, reduced ALT and AST levels, and enhanced antioxidant enzyme activities, suggesting hepatoprotective effects via the Keap1/Nrf2 pathway. 47 compounds were identified in JEAE, and fourteen flavonoids, including two novel compounds (1 and 2), were isolated from the JEAE fraction. Compounds 1, 3, 5, 8, and 14 notably protected HepG2 cells from oxidative damage, reduced ROS levels, and maintained mitochondrial function. These compounds also showed strong binding affinities to Keap1 and other antioxidant receptors, with molecular dynamics simulations confirming their stability and binding potential as effective hepatoprotective agents.

CONCLUSION

This study demonstrates that the ethyl acetate fraction of Desmodium heterocarpon (JEAE) exhibits significant hepatoprotective effects, largely attributed to its flavonoid-rich composition. The protective effects are mediated through antioxidant pathways, particularly the Keap1/Nrf2 signaling pathway. Newly identified isoflavanes and other flavonoids in JEAE show strong potential as bioactive compounds, with stability and binding affinities supporting their role in reducing oxidative stress. These findings suggest D. heterocarpon as a promising source of hepatoprotective agents and provide a foundation for further exploration of its therapeutic applications.

The tradeoff between the efficacy of calcineurin inhibitors: prevention of allograft rejection vs. post-transplant renal and cardiovascular complications

Solid organ transplantation has emerged as a crucial intervention in the field of medicine. During transplantation, our human body perceives the organ as an exogenous entity or graft, initiating an immune reaction to eliminate it. This immune response ultimately culminates in the rejection of the graft. So, to mitigate the possibility of graft rejection, implementing immune suppression is imperative. In this context, the utilization of calcineurin inhibitors (CNIs) assumes a pivotal role. Calcineurin inhibitors significantly preserve immunosuppression following solid organ transplantation. Calcineurin inhibitors have considerably improved short-term results in renal transplantation by reducing acute rejection rates. Concerning the limited therapeutic window of these medications, careful monitoring of pharmacological treatment and individual doses is required. However, a significant number of patients do experience CNI toxicity. Side effects of CNIs include renal failure, hypertension, respiratory disorders, gastrointestinal damage, gingivitis, and so on. Higher trough level of the drug causes acute nephrotoxicity, which is of three types: functional toxicity, tubular toxicity, and vascular toxicity. Acute nephrotoxicity, if untreated, leads to irreversible, progressive deterioration of allograft function, leading to chronic nephrotoxicity. Cardiovascular toxicity of CNIs includes atrial hypertension caused by vasoconstriction of the afferent arteriole, vascular remodeling, hypertrophy, dyslipidemia, and also the onset of diabetes. Such clinical complications further affect the patient's survivability and subjective well-being, possibly leading to graft loss. This review focuses on the most severe side effects of CNIs: renal and cardiovascular toxicity.

In vitro, in vivo and in silico antiplasmodial profiling of the aqueous extract of Hibiscus asper HOOK F. Leaf (Malvaceae)

ETHNOPHARMACOLOGICAL RELEVANCE

Plasmodium resistance to antimalarial drugs raises the urgent need to seek for alternative treatments. Aqueous extract of Hibiscus asper leaves is currently used in malaria management but remains less documented.

AIM OF THE STUDY

The study aims to evaluate antimalarial effects of the aqueous extract of Hibiscus asper. UHPLC/MS, was used to identify some likely compounds present in the plant that were thereafter docked to some malaria parasite proteins.

STUDY DESIGN

In vitro anti-plasmodium and antioxidant, UHPLC/Ms analysis, in vivo antimalarial of the plant extract, and in silico molecular docking prediction of some identified compounds were performed to investigate the pharmacological effects of H. asper.

MATERIAL AND METHODS

The in vitro antiplasmodial activity of the extract was carried out on Plasmodium falciparum strains using SYBR-green dye; then, the curative antimalarial activity was conducted on Plasmodium berghei NK65-infected male Wistar rats. The UHPLC/MS analysis was used to identify plant compounds, followed by interactions (docking affinity) between some compounds and parasitic enzymes such as P. falciparum purine nucleoside phosphorylase (2BSX) and 6-phosphogluconate dehydrogenase (6FQY) to explore potential mechanisms of action at the molecular level.

RESULTS

No hemolysis effect of the extract was observed at concentrations up to 100 mg/mL. In vitro test of the aqueous leaves extract of H. asper showed inhibitory activity against P. falciparum Dd2 and 3D7 strains with IC50 values of 19.75 and 21.97 μg/mL, respectively. The curative antimalarial test of the H. asper extract in infected rats exhibited significant inhibition of the parasite growth (p < 0.001) with inhibition percentage of 95.11%, 97.68% and 95.59% at all the doses (50, 100 and 200 mg/kg) respectively. The extract corrected major physiological alterations such as liver and kidney impairments, oxidative stress and architectural disorganization in liver, spleen and kidneys tissues. The UHPLC/MS analysis identified 7 compounds, namely chlorogenic acid, azulene, quercetin, rhodine, 1-ethyl-2,4-dimethyl benzene and phthalan. Out of seven compounds identified in the extract quercetin and phthalan showed higher in silico inhibitory activity against P. falciparum purine nucleoside phosphorylase and Plasmodium falciparum 6-phosphosgluconate dehydrogenase parasite enzymes.

CONCLUSION

These findings indicate that H. asper could be a promising complementary medicine to manage malaria. Meanwhile, the affinity of annoted compounds with these enzymes should be further confirmed.

The Effectiveness of Levamisole and Broccoli in Lead Poisoning: Hematobiochemical Changes and Tissue Damage in the Liver, Kidney, and Spleen of Wistar Rats

Lead, a heavy metal, has emerged as one of the most significant pollutants, bearing irreversible consequences on human and animal health in conjunction with industrial development. Presently, the use of medicinal plants to alleviate the adverse effects of heavy metal toxicity has captured the attention of researchers. Hence, the objective of this study was to assess the impact of levamisole and broccoli extract on the electrophoretic pattern of serum proteins, hematological parameters, and histopathological alterations in the liver, kidney, and spleen tissues within a lead poisoning model of rats. This experimental investigation spanned 28 days, involving 42 male Wistar rats categorized into seven groups: a control group, a lead acetate (AL) group administered at 1000 ppm in drinking water, a broccoli (B) group at 300 mg/kg/day, a levamisole (LE) group at 2.5 mg/kg/day, and combination groups of lead and broccoli (AL + B), lead and levamisole (AL + LE), and lead, broccoli, and levamisole (AL + LE + B). Upon completion of the study, hematological and biochemical parameters were assessed, and serum protein concentrations were analyzed using electrophoresis. Liver, kidney, and spleen tissues were fixed and subjected to histopathological examination with H&E staining. The findings indicated a significant decrease in white blood cells (WBC), red blood cells (RBC), and hemoglobin (Hb) levels in the AL group compared to other groups (p < 0.01). Conversely, the B group exhibited a notable increase in RBC and WBC compared to the AL group (p < 0.05). The most pronounced lead-induced damage was observed in the liver, resulting in elevated levels of specific enzymes such as AST and ALT in the AL group, accompanied by a decline in albumin and total protein (p < 0.001). A reduction in globulin levels, including Beta-2 globulin, was noted in the AL + B and AL + LE groups compared to the AL group (p < 0.001,  p < 0.05). Histopathological findings also unveiled increased infiltration of inflammatory cells and hemorrhage in the liver tissue, followed by the spleen, significantly higher in the AL group compared to other experimental groups (p < 0.05). Additionally, congestion and inflammation were evident in the spleen tissue compared to other groups. These tissue damages were mitigated in other combination treatment groups. Based on the aforementioned results, the combination of broccoli and levamisole is deemed effective in ameliorating liver and spleen injuries caused by lead and enhancing biochemical parameters and serum proteins.

Phenolic Composition of Crataegus monogyna Jacq. Extract and Its Anti-Inflammatory, Hepatoprotective, and Antileukemia Effects

Crataegus monogyna (C. monogyna) is a prominent plant used in Moroccan traditional medicine. This study investigated the phenolic composition and the anti-inflammatory, the hepatoprotective, and the anticancer activities of a hydroethanolic extract of C. monogyna leaves and stems. Ultra-high-performance liquid chromatography identified the phenolic profile. The in vitro anticancer activity was evaluated using the MTT assay on HL-60 and K-562 myeloleukemia cells and liver (Huh-7) cell lines. The anti-inflammatory effect was assessed in vivo using carrageenan-induced paw edema in rats. The hepatoprotective effect at 300 and 1000 mg/kg doses against the acetaminophen-induced hepatotoxicity on rats was studied for seven days. Additionally, molecular docking simulations were performed to evaluate the extract's inhibitory potential against key targets: lipoxygenase, cytochrome P450, tyrosine kinase, and TRADD. The extract exhibited significant cytotoxic activity against K-562 and HL-60 cells, but not against lung cancer cells (Huh-7 line). The 1000 mg/kg dose demonstrated the most potent anti-inflammatory effect, inhibiting edema by 99.10% after 6 h. C. monogyna extract displayed promising hepatoprotective properties. Procyanidin (-7.27 kcal/mol), quercetin (-8.102 kcal/mol), and catechin (-9.037 kcal/mol) were identified as the most active molecules against lipoxygenase, cytochrome P450, and tyrosine kinase, respectively. These findings highlight the untapped potential of C. monogyna for further exploration in treating liver damage, inflammation, and leukemia.

Prevention of Male Late-Onset Hypogonadism by Natural Polyphenolic Antioxidants

Androgen production primarily occurs in Leydig cells located in the interstitial compartment of the testis. In aging males, testosterone is crucial for maintaining muscle mass and strength, bone density, sexual function, metabolic health, energy levels, cognitive function, as well as overall well-being. As men age, testosterone production by Leydig cells of the testes begins to decline at a rate of approximately 1% per year starting from their 30s. This review highlights recent findings concerning the use of natural polyphenolics compounds, such as flavonoids, resveratrol, and phenolic acids, to enhance testosterone production, thereby preventing age-related degenerative conditions associated with testosterone insufficiency. Interestingly, most of the natural polyphenolic antioxidants having beneficial effects on testosterone production tend to enhance the expression of the steroidogenic acute regulatory protein (Star) gene in Leydig cells. The STAR protein facilitates the entry of the steroid precursor cholesterol inside mitochondria, a rate-limiting step for androgen biosynthesis. Natural polyphenolic compounds can also improve the activities of steroidogenic enzymes, hypothalamus-pituitary gland axis signaling, and testosterone bioavailability. Thus, many polyphenolic compounds such as luteolin, quercetin, resveratrol, ferulic acid phenethyl ester or gigantol may be promising in delaying the initiation of late-onset hypogonadism accompanying aging in males.

Quercetin attenuates cisplatin-induced mitochondrial apoptosis via PI3K/Akt mediated inhibition of oxidative stress in pericytes and improves the blood labyrinth barrier permeability

Cisplatin (CDDP) is broadly employed to treat different cancers, whereas there are no drugs approved by the Food and Drug Administration (FDA) for preventing its side effects, including ototoxicity. Quercetin (QU) is a widely available natural flavonoid compound with anti-tumor and antioxidant properties. The research was designed to explore the protective effects of QU on CDDP-induced ototoxicity and its underlying mechanisms in male C57BL/6 J mice and primary cultured pericytes (PCs). Hearing changes, morphological changes of stria vascularis, blood labyrinth barrier (BLB) permeability and expression of apoptotic proteins were observed in vivo by using the auditory brainstem response (ABR) test, HE staining, Evans blue staining, immunohistochemistry, western blotting, etc. Oxidative stress levels, mitochondrial function and endothelial barrier changes were observed in vitro by using DCFH-DA probe detection, flow cytometry, JC-1 probe, immunofluorescence and the establishment in vitro BLB models, etc. QU pretreatment activates the PI3K/AKT signaling pathway, inhibits CDDP-induced oxidative stress, protects mitochondrial function, and reduces mitochondrial apoptosis in PCs. However, PI3K/AKT specific inhibitor (LY294002) partially reverses the protective effects of QU. In addition, in vitro BLB models were established by coculturing PCs and endothelial cells (ECs), which suggests that QU both reduces the CDDP-induced apoptosis in PCs and improves the endothelial barrier permeability. On the whole, the research findings suggest that QU can be used as a novel treatment to reduce CDDP-induced ototoxicity.

Hovenia dulcis: a Chinese medicine that plays an essential role in alcohol-associated liver disease

Globally, alcohol-associated liver disease (ALD) has become an increased burden for society. Disulfirams, Benzodiazepines (BZDs), and corticosteroids are commonly used to treat ALD. However, the occurrence of side effects such as hepatotoxicity and dependence, impedes the achievement of desirable and optimal therapeutic efficacy. Therefore, there is an urgent need for more effective and safer treatments. Hovenia dulcis is an herbal medicine promoting alcohol removal clearance, lipid-lowering, anti-inflammatory, and hepatoprotective properties. Hovenia dulcis has a variety of chemical components such as dihydromyricetin, quercetin and beta-sitosterol, which can affect ALD through multiple pathways, including ethanol metabolism, immune response, hepatic fibrosis, oxidative stress, autophagy, lipid metabolism, and intestinal barrier, suggesting its promising role in the treatment of ALD. Thus, this work aims to comprehensively review the chemical composition of Hovenia dulcis and the molecular mechanisms involved in the process of ALD treatment.

Boldine protects against carbon tetrachloride-induced chronic liver injury by regulating NF-κB signaling pathway

Sustained liver injuries predominantly promote oxidative stress and inflammation that lead to the progression of chronic liver disease (CLD), including fibrosis, cirrhosis, and hepatocellular carcinoma. Boldine, an alkaloid isolated from Peumus boldus, has been shown to have antioxidant and anti-inflammatory effects. Currently, there is no definitive treatment option available for CLD. Therefore, we investigated the hepatoprotective effect of boldine against carbon tetrachloride (CCl4 )-induced chronic liver injury in rats. CCl4 (2 mL/kg., b.w., i.p.) was administered twice weekly for 5 weeks to induce chronic liver injury in rats. Separate groups of rats were given boldine (20 mg/kg b.w., and 40 mg/kg b.w.) and silymarin (100 mg/kg b.w.) orally, daily. Serum transaminases, lipid peroxidation, and antioxidant levels were measured, and nuclear factor-κB (NF-κB), tumor necrosis factor-α (TNF-α), cyclooxygenase-2 (cox-2), interleukin-1 β (IL-1β), and α-smooth muscle actin (α-SMA) gene and protein expressions were evaluated. CCl4 administration increased liver marker enzymes of hepatotoxicity in serum and oxidative stress markers, inflammatory genes and α-smooth muscle actin expression in liver tissue. Boldine concurrent treatment suppressed CCl4 -induced elevation of transaminase levels in serum, restored enzymic and non-enzymic antioxidants, and downregulated NF-κB, TNF-α, Cox-2 and IL-1β expressions, thereby suppressing hepatic inflammation. Boldine administration also repressed α-SMA expression. The results of this study demonstrate the antioxidant, anti-inflammatory, and antifibrotic properties of boldine, and it can be a potential therapeutic candidate in the treatment of CLD.

Therapeutic detoxification of quercetin for aflatoxin B1-related toxicity: Roles of oxidative stress, inflammation, and metabolic enzymes

Aflatoxins (AFTs), a type of mycotoxin mainly produced by Aspergillus parasiticus and Aspergillus flavus, could be detected in food, feed, Chinese herbal medicine, grain crops and poses a great threat to public health security. Among them, aflatoxin B1 (AFB1) is the most toxic one. Exposure to AFB1 poses various health risks to both humans and animals, including the development of chronic inflammatory diseases, cardiovascular diseases, neurodegenerative diseases, and cancer. The molecular mechanisms underlying these risks are intricate and dependent on specific contexts. This review primarily focuses on summarizing the protective effects of quercetin, a natural phenolic compound, in mitigating the toxic effects induced by AFB1 in both in vitro experiments and animal models. Additionally, the review explores the molecular mechanisms that underlie these protective effects. Quercetin has been demonstrated to not only have the direct inhibitory action on the production of AFTs from Aspergillus, both also possess potent ameliorative effects against AFB1-induced cytotoxicity, hepatotoxicity, and neurotoxicity. These effects are attributed to the inhibition of oxidative stress, mitochondrial dysfunction, mitochondrial apoptotic pathway, and inflammatory response. It could also directly target several metabolic enzymes (i.e., CYP3As and GSTA1) to reduce the production of toxic metabolites of AFB1 within cells, then reduce AFB1-induced cytotoxicity. In conclusion, this review highlights quercetin is a promising detoxification agent for AFB1. By advancing our understanding of the protective mechanisms offered by quercetin, we aim to contribute to the development of effective detoxification agents against AFB1, ultimately promoting better health outcomes.

Preparation and characterization of particle-filled microgels by chemical cross-linking based on zein and carboxymethyl starch for delivering the quercetin

This work aimed to develop novel particle-filled microgels based on zein and carboxymethyl starch for delivering quercetin (Que). The anti-solvent precipitation and chemical cross-linking methods were combined to produce the zein-carboxymethyl starch particle-filled microgels (SM-Z). The critical finding of the study was that adding zein nanoparticles significantly improved the strength, water holding capacity, and thermal stability of carboxymethyl starch microgel (SM). Besides, SM-Z had good biodegradability, and the particle size was about 44-61 μm. SM-Z successfully encapsulated Que with a high encapsulation efficiency of 86.7 %. Que-loaded SM-Z (Q/SM-Z) significantly enhanced 30 d storage and UV light stability (up to 89.4 % retention rate) of Que than the Que-loaded SM (Q/SM). Q/SM-Z exhibited pH-responsive swelling behavior, and the swelling was greatest in the simulated intestinal fluid (pH = 7). Besides, the Q/SM-Z showed good stability in simulated gastric fluids and sustained release of Que in simulated intestinal fluids, 72.5 % Que was released at 8 h. During Que transport in Caco-2 cell monolayers, Q/SM (5.8 %) and Q/SM-Z (9.7 %) were significantly higher than free Que (1.93 %). Therefore, as an oral delivery system for hydrophobic active substances, SM-Z possesses good biodegradability and pH-responsive intestinal-targeted delivery capability, providing a new strategy for designing starch-based encapsulation materials.

Quercetin protects cadmium-induced renal injuries in mice by inhibiting cell pyroptosis

The toxic heavy metal cadmium (Cd) has a significant impact on kidney health. Documents manifested that non-toxic flavonoid quercetin can reduce Cd-induced kidney damage by reducing oxidative stress and inhibiting apoptosis, while the effect of quercetin on Cd-induced renal cell pyroptosis has not been elucidated. In this study, we established a model of Cd poisoning treated with quercetin both in vitro and in vivo. Results revealed that quercetin effectively reversed the decrease in Cd-induced cell viability. Furthermore, Cd increased blood urea nitrogen while reducing GPX and SOD levels, caused histopathological injuries in kidney with a significantly elevated cell pyroptosis characterized by enhanced levels of proteins representing assembly (NLRP3) and activation (pro IL-1β, cleaved IL-1β, and IL-18) of NLRP3 inflammasome as well as pyroptosis executor (pro caspase-1, cleaved caspase-1). However, quercetin administration alleviated kidney injuries above by decreasing cell pyroptosis. Overall, it suggests that kidney cells are susceptible to pyroptotic cell death due to Cd exposure; while quercetin exhibits protective effects through cell pyroptosis inhibition.

Advance in the pharmacological effects of quercetin in modulating oxidative stress and inflammation related disorders

Numerous pharmacological effects of quercetin have been illustrated, including antiinflammation, antioxidation, and anticancer properties. In recent years, the antioxidant activity of quercetin has been extensively reported, in particular, its impacts on glutathione, enzyme activity, signaling transduction pathways, and reactive oxygen species (ROS). Quercetin has also been demonstrated to exert a striking antiinflammatory effect mainly by inhibiting the production of cytokines, reducing the expression of cyclooxygenase and lipoxygenase, and preserving the integrity of mast cells. By regulating oxidative stress and inflammation, which are regarded as two critical processes involved in the defense and regular physiological operation of biological systems, quercetin has been validated to be effective in treating a variety of disorders. Symptoms of these reactions have been linked to degenerative processes and metabolic disorders, including metabolic syndrome, cardiovascular, neurodegeneration, cancer, and nonalcoholic fatty liver disease. Despite that evidence demonstrates that antioxidants are employed to prevent excessive oxidative and inflammatory processes, there are still concerns regarding the expense, accessibility, and side effects of agents. Notably, natural products, especially those derived from plants, are widely accessible, affordable, and generally safe. In this review, the antioxidant and antiinflammatory abilities of the active ingredient quercetin and its application in oxidative stress-related disorders have been outlined in detail.

Nutritional intervention is promising in alleviating liver injury during tuberculosis treatment: a review

Liver injury is a main adverse effect of first-line tuberculosis drugs. Current management of tuberculosis-drug-induced liver injury (TBLI) mainly relies on withdrawing tuberculosis drugs when necessary. No effective treatment exists. Various nutrients and functional food ingredients may play a protective role in TBLI. However, a comprehensive review has not been conducted to compare the effects of these nutrients and functional food ingredients. We searched Pubmed and Web of Science databases from the earliest date of the database to March 2023. All available in-vitro, animal and clinical studies that examined the effects of nutritional intervention on TBLI were included. The underlying mechanism was briefly reviewed. Folic acid, quercetin, curcumin, Lactobacillus casei, spirulina and Moringa oleifera possessed moderate evidence to have a beneficial effect on alleviating TBLI mostly based on animal studies. The evidence of other nutritional interventions on TBLI was weak. Alleviating oxidative stress and apoptosis were the leading mechanisms for the beneficial effects of nutritional intervention on TBLI. In conclusion, a few nutritional interventions are promising for alleviating TBLI including folic acid, quercetin, curcumin, L. casei, spirulina and M. oleifera, the effectiveness and safety of which need further confirmation by well-designed randomized controlled trials. The mechanisms for the protective role of these nutritional interventions on TBLI warrant further study, particularly by establishing the animal model of TBLI using the tuberculosis drugs separately.

The Potential Effects of Quercetin-Loaded Nanoliposomes on Amoxicillin/Clavulanate-Induced Hepatic Damage: Targeting the SIRT1/Nrf2/NF-κB Signaling Pathway and Microbiota Modulation

Amoxicillin/clavulanate (Co-Amox), a commonly used antibiotic for the treatment of bacterial infections, has been associated with drug-induced liver damage. Quercetin (QR), a naturally occurring flavonoid with pleiotropic biological activities, has poor water solubility and low bioavailability. The objective of this work was to produce a more bioavailable formulation of QR (liposomes) and to determine the effect of its intraperitoneal pretreatment on the amelioration of Co-Amox-induced liver damage in male rats. Four groups of rats were defined: control, QR liposomes (QR-lipo), Co-Amox, and Co-Amox and QR-lipo. Liver injury severity in rats was evaluated for all groups through measurement of serum liver enzymes, liver antioxidant status, proinflammatory mediators, and microbiota modulation. The results revealed that QR-lipo reduced the severity of Co-Amox-induced hepatic damage in rats, as indicated by a reduction in serum liver enzymes and total liver antioxidant capacity. In addition, QR-lipo upregulated antioxidant transcription factors SIRT1 and Nrf2 and downregulated liver proinflammatory signatures, including IL-6, IL-1β, TNF-α, NF-κB, and iNOS, with upregulation in the anti-inflammatory one, IL10. QR-lipo also prevented Co-Amox-induced gut dysbiosis by favoring the colonization of Lactobacillus, Bifidobacterium, and Bacteroides over Clostridium and Enterobacteriaceae. These results suggested that QR-lipo ameliorates Co-Amox-induced liver damage by targeting SIRT1/Nrf2/NF-κB and modulating the microbiota.

Impact of antioxidant supplementation during in vitro culture of ovarian preantral follicles: A review

The in vitro culture systems of ovarian preantral follicles have been developed for studying follicular and oocyte growth, for future use of immature oocytes as sources of fertilizable oocytes and for screening ovarian toxic substances. One of the key limitations of the in vitro culture of preantral follicles is the oxidative stress by accumulation of reactive oxygen species (ROS), which can impair follicular development and oocyte quality. Several factors are associated with oxidative stress in vitro, which implies the need for a rigorous control of the conditions as well as addition of antioxidant agents to the culture medium. Antioxidant supplementation can minimize or eliminate the damage caused by ROS, supporting follicular survival and development and producing mature oocytes competent for fertilization. This review focuses on the use of antioxidants and their role in preventing follicular damage caused by oxidative stress in the in vitro culture of preantral follicles.

Current and emerging applications of saccharide-modified chitosan: a critical review

Chitin, as the main component of the exoskeleton of Arthropoda, is a highly available natural polymer that can be processed into various value-added products. Its most important derivative, i.e., chitosan, comprising β-1,4-linked 2-amino-2-deoxy-β-d-glucose (deacetylated d-glucosamine) and N-acetyl-d-glucosamine units, can be prepared via alkaline deacetylation process. Chitosan has been used as a biodegradable, biocompatible, non-antigenic, and nontoxic polymer in some in-vitro applications, but the recently found potentials of chitosan for in-vivo applications based on its biological activities, especially antimicrobial, antioxidant, and anticancer activities, have upgraded the chitosan roles in biomaterials. Chitosan approval, generally recognized as a safe compound by the United States Food and Drug Administration, has attracted much attention toward its possible applications in diverse fields, especially biomedicine and agriculture. Even with some favorable characteristics, the chitosan's structure should be customized for advanced applications, especially due to its drawbacks, such as low drug-load capacity, low solubility, high viscosity, lack of elastic properties, and pH sensitivity. In this context, derivatization with relatively inexpensive and highly available mono- and di-saccharides to soluble branched chitosan has been considered a "game changer". This review critically reviews the emerging technologies based on the synthesis and application of lactose- and galactose-modified chitosan as two important chitosan derivatives. Some characteristics of chitosan derivatives and biological activities have been detailed first to understand the value of these natural polymers. Second, the saccharide modification of chitosan has been discussed briefly. Finally, the applications of lactose- and galactose-modified chitosan have been scrutinized and compared to native chitosan to provide an insight into the current state-of-the research for stimulating new ideas with the potential of filling research gaps.

Therapeutic Potential of Quercetin and its Derivatives in Epilepsy: Evidence from Preclinical Studies

Quercetin is a polyphenolic bioactive compound highly enriched in dietary fruits, vegetables, nuts, and berries. Quercetin and its derivatives like rutin and hyperoside are known for their beneficial effects in various neurological conditions including epilepsy. The clinical studies of quercetin and its derivatives in relation to epilepsy are limited. This review provides the evidence of most recent knowledge of anticonvulsant properties of quercetin and its derivatives on preclinical studies. Additionally, the studies demonstrating antiseizure potential of various plants extracts enriched with quercetin and its derivatives has been included in this review. Herein, we have also discussed neuroprotective effect of these bioactive compound and presented underlying mechanisms responsible for anticonvulsant properties in brief. Finally, limitations of quercetin and its derivatives as antiseizure compounds as well as possible strategies to enhance efficacy have also been discussed.

Improving Lipophagy by Restoring Rab7 Cycle: Protective Effects of Quercetin on Ethanol-Induced Liver Steatosis

Chronic alcohol consumption retards lipophagy, which contributes to the pathogenesis of liver steatosis. Lipophagy-related Rab7 has been presumed as a crucial regulator in the progression of alcohol liver disease despite elusive mechanisms. More importantly, whether or not hepatoprotective quercetin targets Rab7-associated lipophagy disorder is unknown. Herein, alcoholic fatty liver induced by chronic-plus-single-binge ethanol feeding to male C57BL/6J mice was manifested by hampering autophagosomes formation with lipid droplets and fusion with lysosomes compared with the normal control, which was normalized partially by quercetin. The GST-RILP pulldown assay of Rab7 indicated an improved GTP-Rab7 as the quercetin treatment for ethanol-feeding mice. HepG2 cells transfected with CYP2E1 showed similar lipophagy dysfunction when exposed to ethanol, which was blocked when cells were transfected with siRNA-Rab7 in advance. Ethanol-induced steatosis and autophagic flux disruption were aggravated by the Rab7-specific inhibitor CID1067700 while alleviated by transfecting with the Rab7Wt plasmid, which was visualized by immunofluorescence co-localization analysis and mCherry-GFP-LC3 transfection. Furthermore, TBC1D5, a Rab GTPase-activating protein for the subsequent normal circulation of Rab7, was downregulated after alcohol administration but regained by quercetin. Rab7 circulation retarded by ethanol and corrected by quercetin was further revealed by fluorescence recovery after photobleaching (FRAP). Altogether, quercetin attenuates hepatic steatosis by normalizing ethanol-imposed Rab7 turnover disorders and subsequent lipophagy disturbances, highlighting a novel mechanism and the promising prospect of quercetin-like phytochemicals against the crucial first hit from alcohol.

Investigating the efficiency and tolerability of traditional Chinese formulas combined with antiarrhythmic agents for paroxysmal atrial fibrillation: A systematic review and Bayesian network meta-analysis

BACKGROUND

The combination of antiarrhythmic drugs with traditional Chinese formulas are used treatments for the management of paroxysmal atrial fibrillation (PAF). However, the most effective treatment for PAF has yet to be been determined. A Bayesian network meta-analysis study was thus performed for comparing the relative efficacy and tolerability of different treatment alternatives.

METHODS

A comprehensive literature review of randomized controlled trials (RCTs) is performed from eight database. Maintenance rate of sinus rhythm (MRSR), p-wave dispersion (Pd), left atrium diameter (LAD), left ventricular ejection fraction (LVEF), and adverse events (AEs) were used as outcomes. We also estimated treatment rank based on the surface under the cumulative ranking curve (SUCRA). This study was performed using a Bayesian network meta-analysis with a random-effects model.

FINDINGS

After screening, 59 RCTs involving 5,543 patients and 16 treatments were included. The results showed that Shensong-Yangxin capsule (SSYX) plus amiodarone (81%) was the most effective treatment for MRSR according to the value of SUCRA, followed by Wenxin-Keli granules (WXKL) plus amiodarone (73%). Meanwhile, SSYX plus amiodarone (7%) was most likely to reduce Pd, followed by SSYX plus metoprolol (23%), WXKL plus amiodarone (26%), WXKL plus bisoprolol (27%). Furthermore, SSYX plus amiodarone (4%) was more effective in improving LAD. WXKL plus amiodarone was preferred because it had the lowest toxicity. For benefit-risk ratio, amiodarone combined with WXKL or SSYX appeared to be the best option.

CONCLUSION

Antiarrhythmic agents combined with traditional Chinese formulas had higher efficacy and lower toxicity than other treatment alternatives. This study might provide reference to help find the better treatment options for PAF.

Quercetin loaded liposomes modified with galactosylated chitosan prevent LPS/D-GalN induced acute liver injury

Quercetin (Que) has been proved to have various biological activities, including anti-oxidation, anti-inflammation and anti-virus, showing great potential in liver protection. However, its water insolubility leads to low bioavailability. Therefore, the development of a suitable drug delivery fashion is imminent. In recent years, liposomes have been widely used in the fields of drug delivery and gene transfer thanks to the cell membrane like structure, easy surface-modification and high encapsulation efficiency. Herein, we fabricated Que loaded anionic liposomes. Galactosylated chitosan (GC) was simply attached to the surfaces of liposomes through electrostatic adsorption to achieve targeted delivery by binding to asialoglycoprotein receptor (ASGPR). The results showed that Que loaded liposomes modified with GC (GC-Que-Lipo) could enrich the liver in mice through tail vein injection. Liposomes could achieve sustained drug release and GC-Que-Lipo promoted M2 polarization of macrophages. More importantly, it could maintain low content of AST, ALT, ALP and high level of GSH while reducing lipid oxidation, thereby protecting the liver from damage in acute liver injury model. In general, we expect to be able to acquire targeted and efficient delivery of quercetin through a facile approach, thus fulfill the prevention and treatment of liver diseases.

Hepatotoxicity of food-borne mycotoxins: molecular mechanism, anti-hepatotoxic medicines and target prediction

Mycotoxins are metabolites produced by fungi. The widespread contamination of food and feed by mycotoxins is a global food safety problem and a serious threat to people's health. Most food-borne mycotoxins have strong hepatotoxicity. However, no effective methods have been found to prevent or treat Mycotoxin- Induced Liver Injury (MILI) in clinical and animal husbandry. In this paper, the molecular mechanisms and potential anti-MILI medicines of six food-borne MILI are reviewed, and their targets are predicted by network toxicology, which provides a theoretical basis for further study of the toxicity mechanism of MILI and the development of effective strategies to manage MILI-related health problems in the future and accelerate the development of food safety.

Dietary Intake of Vegetables and Cooking Oil Was Associated With Drug-Induced Liver Injury During Tuberculosis Treatment: A Preliminary Cohort Study

Background and Purpose: Drug-induced liver injury is challenging during tuberculosis treatment. There is no epidemiological data investigating the relation between dietary intake and the risk of drug-induced liver injury during tuberculosis treatment. The aim of this study is to investigate the association of food and nutrient intake with the incidence of tuberculosis-drug-induced liver injury.

Methods: A cohort study was conducted in two city-level tuberculosis-specialized hospitals in Linyi City and Qingdao City, China from January 2011 to December 2013. The dietary intake was assessed by a 3-day 24-h food recall survey and a standard food-frequency questionnaire. The liver functions including aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were monitored throughout the 6-month tuberculosis therapy. Liver injury was defined as ALT or AST higher than two times of the upper limit of normal (ULN). Liver dysfunction was defined as ALT or AST higher than the ULN. The ULN for ALT and AST is 40 U/L. Multivariate logistic regression analyses were performed to determine the dietary factors associated with the incidence of liver injury and liver dysfunction.

Results: A total of 605 patients were included in the analysis. During the treatment, 8.1% patients exhibited liver injury and 23.3% patients exhibited liver dysfunction. A lower intake of vegetables was associated with a higher risk of liver injury [OR (95% CI): 3.50 (1.52–8.08), P = 0.003) and liver dysfunction [OR (95% CI): 2.37 (1.31–4.29), P = 0.004], while a lower intake of cooking oil was associated with a lower risk of liver injury [OR (95% CI): 0.44 (0.20–0.96), P = 0.040)] and liver dysfunction [OR (95% CI): 0.51 (0.31–0.85), P = 0.009].

Conclusion: The current study indicated that the higher risks of tuberculosis-drug-induced liver injury and liver dysfunction were statistically associated with decreased vegetable intake and increased cooking oil intake.

Quercetin promotes osteogenic differentiation and antioxidant responses of mouse bone mesenchymal stem cells through activation of the AMPK/SIRT1 signaling pathway

Decrepitude and apoptosis of bone mesenchymal stem cells (BMSCs) induced by reactive oxygen species (ROS) lead to inhibited osteogenic differentiation, causing decreased bone density and osteoporosis. Quercetin, a bioactive component of Solanum muricatum extracts, promotes the osteogenic differentiation of BMSCs and ameliorates the symptoms of osteoporosis in vivo. However, the detailed mechanism underlying this process remains unclear. The study aims to reveal the regulatory mechanism of quercetin in BMSCs. Mouse BMSCs (mBMSCs) were isolated from the bone marrow and characterized by flow cytometry. QRT-PCR and western blot assays were performed to evaluate the expression levels of related genes and proteins. Alkaline phosphatase (ALP) staining and Oil Red O staining of lipids were used to estimate the osteogenesis and adipogenesis levels of mBMSCs, respectively. Quercetin treatment (2 and 5 μM) induced significant upregulation of antioxidant enzymes, SOD1 and SOD2, in mBMSCs. Quercetin promoted osteogenic differentiation and inhibited adipogenic differentiation of mBMSCs. Quercetin treatment enhanced the phosphorylation of AMPK protein and upregulated the expression of SIRT1, thus activating the AMPK/SIRT1 signaling pathway in mBMSCs. Quercetin promoted osteogenic differentiation and antioxidant responses of mBMSCs by activating the AMPK/SIRT1 signaling pathway.

Network pharmacology modeling identifies synergistic interaction of therapeutic and toxicological mechanisms for Tripterygium hypoglaucum Hutch

Background

Tripterygium hypoglaucum Hutch (THH) both has prominent efficacy and unwarranted toxicity in the treatment of autoimmune diseases. Nevertheless, its pharmacological and toxicological profiles still remain to be elucidated. In the current study, the network pharmacology approach was applied to identify synergistic interaction and mechanism of efficacy and toxicity for THH from a holistic perspective.

Methods

The compounds from THH were collected using literature retrieval and relevant databases. After the production of putative therapeutic targets for dominant diseases and harmful targets of adverse reactions (ADRs) induced by THH, the protein-protein interactions (PPIs), topological analysis and pathway enrichment were established to distinguish the hub targets and pathways. Additionally, the binding activity of candidate ingredients with core targets were revealed by molecular docking simulation.

Results

A total of eight bioactive components in THH were enrolled, and 633 targets were responsible for rheumatoid arthritis (RA), 1067 targets were corresponding to systemic lupus erythematosus (SLE), 1318 targets of ADRs were obtained. The results of enrichment analysis among THH-RA, THH-SLE and THH-ADR networks indicated that pathway in cancer, hepatitis B, rheumatoid arthritis, and PI3K-Akt signaling pathway might participate in THH for treating RA and SLE. Besides, the mechanism of ADRs that induced by THH were associated with viral carcinogenesis, p53 signaling pathway, PI3K-Akt signaling pathway, and so on. Whereas, these active ingredients of THH exerted the superior binding activities with crucial targets including STAT3, VEGFA, TP53 and MMP9 that functioned synergistically efficacy and toxicity as observed via molecular docking simulation.

Conclusion

The present research preliminarily interpreted the synergistic interaction of therapeutic and toxicological mechanisms for THH through the comprehensive analysis of relationship and binding activity between primary components and core targets, providing a feasible and promising approach to facilitate the development of toxic and irreplaceable herbs.

Boldine treatment protects acetaminophen-induced liver inflammation and acute hepatic necrosis in mice

Drug-induced liver injury (DILI) is a frequent cause responsible for acute liver failure (ALF). Acetaminophen (APAP) is a known hepatotoxin predictably causing intrinsic DILI. At high doses, APAP causes acute liver necrosis and responsible for ALF and liver transplant cases in 50% and 20% of patients, respectively, in the United States alone. Oxidative stress and glutathione depletion are implicated in APAP-induced liver necrosis. Boldine, a plant-derived compound is shown to have promising antioxidant potential. Therefore, this study investigates the protective effect of boldine against APAP-induced acute hepatic necrosis in mice. A single toxic dose of APAP (300 mg/kg b.w. p.o.) was administered in overnight-fasted mice to induce acute liver necrosis. Separately, APAP + boldine and APAP + N-acetylcysteine (NAC) simultaneous treatments were also given. Serum transaminases and reduced glutathione, enzymic antioxidants, tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and, IL-6 were evaluated in liver tissue. Acute APAP intoxication significantly elevated serum marker enzymes of hepatotoxicity. APAP administration increased lipid peroxidation, TNF-α, IL-1β, and IL-6 protein expressions. The enzymic antioxidants and reduced glutathione levels were decreased in liver tissue of APAP intoxicated mice. Boldine and NAC simultaneous treatments prevented APAP-induced oxidative stress, inflammation, and necrosis. The results of this study suggest the crucial role of boldine to protect against APAP induced hepatotoxicity by virtue of its antioxidant and anti-inflammatory properties.

Antiviral Role of Phenolic Compounds against Dengue Virus: A Review

Phenolic compounds have been related to multiple biological activities, and the antiviral effect of these compounds has been demonstrated in several viral models of public health concern. In this review, we show the antiviral role of phenolic compounds against dengue virus (DENV), the most widespread arbovirus globally that, after its re-emergence, has caused multiple epidemic outbreaks, especially in the last two years. Twenty phenolic compounds with anti-DENV activity are discussed, including the multiple mechanisms of action, such as those directed against viral particles or viral proteins, host proteins or pathways related to the productive replication viral cycle and the spread of the infection.

Metabolomics analysis of the effects of quercetin on renal toxicity induced by cadmium exposure in rats

This study aims to explore the protective effects of quercetin against cadmium-induced nephrotoxicity utilizing metabolomics methods. Male Sprague-Dawley rats were randomly assigned to six groups: control, different dosages of quercetin (10 and 50 mg/kg·bw, respectively), CdCl2 (4.89 mg/kg·bw) and different dosages quercetin plus CdCl2 groups. After 12 weeks, the kidneys were collected for metabolomics analysis and histopathology examination. In total, 11 metabolites were confirmed, the intensities of which significantly changed (up-regulated or down-regulated) compared with the control group (p < 0.00067). These metabolites include xanthosine, uric acid (UA), guanidinosuccinic acid (GSA), hypoxanthine (Hyp), 12-hydroxyeicosatetraenoic acid (tetranor 12-HETE), taurocholic acid (TCA), hydroxyphenylacetylglycine (HPAG), deoxyinosine (DI), ATP, formiminoglutamic acid (FIGLU) and arachidonic acid (AA). When high-dose quercetin and cadmium were given to rats concurrently, the intensities of above metabolites significantly restored (p < 0.0033 or p < 0.00067). The results showed quercetin attenuated Cd-induced nephrotoxicity by regulating the metabolism of lipids, amino acids, and purine, inhibiting oxidative stress, and protecting kidney functions.

Anwulignan Alleviates Carbon Tetrachloride-Induced Acute Liver Injury in Mice

Acute liver injury is a serious threat to human health. Complementary therapy including a traditional Chinese herb has been used for the prevention and treatment of liver injuries. Schisandrae sphenantherae fructus (Schisandra) is the mature dry fruit of Schisandra sphenanthera Rehd. et Wils. Wuzhi capsule, a preparation containing Schisandra and its main component anwulignan, is used to treat hepatitis and hepatic insufficiency caused by viruses and drugs in the clinic. However, to date, there has been little study to reveal the effect of anwulignan in the protection of the liver. Therefore, in this study, we hypothesized that anwulignan could protect carbon tetrachloride (CCl4)-induced acute liver injury in mice. Anwulignan was shown to reduce significantly the liver index, decrease liver histopathological injury, decrease the serum level of aspartate aminotransferase and alanine aminotransferase, increase the activities of superoxide dismutase (SOD) and glutathione peroxidase, reduce liver malondialdehyde content, and downregulate the expression levels of interleukin (IL)-6, IL-1β, and tumor necrosis factor-α in the liver tissue, as well as the protein expression levels of receptor-interacting serine/threonine-protein kinase 1 (RIPK1), RIPK3, and phosphorylated mixed lineage kinase domain-like protein. All these results suggest that anwulignan can alleviate the CCl4-induced acute liver injury in mice, which may be related to its antioxidant, anti-inflammation, and inhibition of liver cell necroptosis effects.

In Vivo Anti-inflammatory Potential of Viscozyme®-Treated Jujube Fruit

The fruit of Ziziphus jujuba, commonly called jujube, has long been consumed for its health benefits. The aim of this study was to examine the protective effect of dietary supplementation of enzymatically hydrolyzed jujube against lung inflammation in mice. The macerated flesh of jujube was extracted with aqueous ethanol before and after Viscozyme treatment. The extract of enzyme-treated jujube, called herein hydrolyzed jujube extract (HJE), contained higher levels of quercetin, total phenolics, and flavonoids, and exhibited more effective radical-scavenging abilities in comparison to non-hydrolyzed jujube extract (NHJE). HJE treatment decreased production of inflammation-associated molecules, including nitric oxide and pro-inflammatory cytokines from activated Raw 264.7 or differentiated THP-1 cells. HJE treatment also reduced expression of nuclear factor-κB and its downstream proteins in A549 human lung epithelial cells. Moreover, oral supplementation of 1.5 g of HJE per kg of body weight (BW) attenuated histological lung damage, decreased plasma cytokines, and inhibited expression of inflammatory proteins and oxidative stress mediators in the lungs of mice exposed to benzo(a)pyrene at 50 mg/kg BW. Expression levels of antioxidant and cytoprotective factors, such as nuclear factor erythroid-derived 2-related factor 2 and heme oxygenase-1, were increased in lung and liver tissues from mice treated with HJE, compared to mice fed NHJE. These findings indicate that dietary HJE can reduce benzo(a)pyrene-induced lung inflammation by inhibiting cytokine release from macrophages and promoting antioxidant defenses in vivo.

Stereological and histopathological evaluation of doxorubicin-induced toxicity in female rats' ovary and uterus and palliative effects of quercetin and vitamin E

Doxorubicin (DOX) is a widely used chemotherapeutic agent with demonstrated reproductive toxicity. This study sought to determine the DOX-induced toxicity in the ovary and uterus and the preventive effects of quercetin (QCT) and vitamin E (Vit.E). Female rats were divided into six groups as follows: control, QCT (20 mg/kg), Vit.E (200 mg/kg), DOX (accumulative 15 mg/kg), DOX/QCT, and DOX/Vit.E. After 3 weeks, the toxicity of DOX in ovarian and uterine tissues and the potential palliative effects of QCT and Vit.E were evaluated by histopathological-stereological methods. The findings indicate a dramatic decline in the number of ovarian follicles (p < 0.001), ovarian and its associated structures volume, the volume of the uterus, its layers, and related structures (p < 0.05). Coadministration of QCT and Vit.E with DOX-treated rats demonstrated an alleviative effect on most of the studied parameters. Nevertheless, few adverse effects were recognized concerning these antioxidants administration (p < 0.05). In conclusion, the findings of this study support the protective role of these dietary supplements in the prevention of DOX-induced toxicity in uterine and ovarian tissues.

Biochemical Characterization of Traditional Varieties of Sweet Pepper (Capsicum annuum L.) of the Campania Region, Southern Italy

Bioactive compounds of different Campania native sweet pepper varieties were evaluated. Polyphenols ranged between 1.37 mmol g-1 and 3.42 mmol g-1, β-carotene was abundant in the red variety "Cazzone" (7.05 μg g-1). Yellow and red varieties showed a content of ascorbic acid not inferior to 0.82 mg g-1, while in some green varieties the presence of ascorbic acid was almost inconsistent. Interrelationships between the parameters analyzed and the varieties showed that ascorbic acid could represent the factor mostly influencing the antioxidant activity. Polyphenol profile was different among the varieties, with a general prevalence of acidic phenols in yellow varieties and of flavonoids in red varieties. Principal Component Analysis, applied to ascorbic acid, total polyphenols and β-carotene, revealed that two of the green varieties ("Friariello napoletano" and "Friariello Sigaretta") were well clustered and that the yellow variety "Corno di capra" showed similarity with the green varieties, in particular with "Friariello Nocerese". This was confirmed by the interrelationships applied to polyphenol composition, which let us to light on a clustering of several red and yellow varieties, and that mainly the yellow "Corno di capra" was closer to the green varieties of "Friariello".

Evaluation of Antioxidant Activity of Spice-Derived Phytochemicals Using Zebrafish

Various dietary phytochemicals seem to display antioxidant activity through the NF-E2-related factor 2 (Nrf2) pathway. However, few studies have demonstrated its antioxidant effect and Nrf2 dependency at the animal level. We constructed a zebrafish-based assay system to analyze the in vivo antioxidant activity of phytochemicals and examined the activity of 10 phytochemicals derived from spices, using this system as a pilot study. Hydrogen peroxide and arsenite were used as oxidative stressors, and Nrf2 dependency was genetically analyzed using an Nrf2-mutant zebrafish line. The activities of curcumin, diallyl trisulfide and quercetin were involved in the reduction of hydrogen peroxide toxicity, while those of cinnamaldehyde, isoeugenol and 6-(methylsulfinyl)hexyl isothiocyanate were involved in the reduction of arsenite toxicity. The antioxidant activities of these phytochemicals were all Nrf2 dependent, with the exception of cinnamaldehyde, which showed strong antioxidant effects even in Nrf2-mutant zebrafish. In summary, we succeeded in constructing an assay system to evaluate the in vivo antioxidant activity of various phytochemicals using zebrafish larvae. Using this system, we found that each spice-derived phytochemical has its own specific property and mechanism of antioxidant action.