Flavonoids and cancer prevention: a review of the evidence

Several lines of antioxidant defense against oxidative stress: antioxidant enzymes, nanomaterials with multiple enzyme-mimicking activities, and low-molecular-weight antioxidants

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are well recognized for playing a dual role, since they can be either deleterious or beneficial to biological systems. An imbalance between ROS production and elimination is termed oxidative stress, a critical factor and common denominator of many chronic diseases such as cancer, cardiovascular diseases, metabolic diseases, neurological disorders (Alzheimer's and Parkinson's diseases), and other disorders. To counteract the harmful effects of ROS, organisms have evolved a complex, three-line antioxidant defense system. The first-line defense mechanism is the most efficient and involves antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). This line of defense plays an irreplaceable role in the dismutation of superoxide radicals (O2•-) and hydrogen peroxide (H2O2). The removal of superoxide radicals by SOD prevents the formation of the much more damaging peroxynitrite ONOO- (O2•-  + NO• → ONOO-) and maintains the physiologically relevant level of nitric oxide (NO•), an important molecule in neurotransmission, inflammation, and vasodilation. The second-line antioxidant defense pathway involves exogenous diet-derived small-molecule antioxidants. The third-line antioxidant defense is ensured by the repair or removal of oxidized proteins and other biomolecules by a variety of enzyme systems. This review briefly discusses the endogenous (mitochondria, NADPH, xanthine oxidase (XO), Fenton reaction) and exogenous (e.g., smoking, radiation, drugs, pollution) sources of ROS (superoxide radical, hydrogen peroxide, hydroxyl radical, peroxyl radical, hypochlorous acid, peroxynitrite). Attention has been given to the first-line antioxidant defense system provided by SOD, CAT, and GPx. The chemical and molecular mechanisms of antioxidant enzymes, enzyme-related diseases (cancer, cardiovascular, lung, metabolic, and neurological diseases), and the role of enzymes (e.g., GPx4) in cellular processes such as ferroptosis are discussed. Potential therapeutic applications of enzyme mimics and recent progress in metal-based (copper, iron, cobalt, molybdenum, cerium) and nonmetal (carbon)-based nanomaterials with enzyme-like activities (nanozymes) are also discussed. Moreover, attention has been given to the mechanisms of action of low-molecular-weight antioxidants (vitamin C (ascorbate), vitamin E (alpha-tocopherol), carotenoids (e.g., β-carotene, lycopene, lutein), flavonoids (e.g., quercetin, anthocyanins, epicatechin), and glutathione (GSH)), the activation of transcription factors such as Nrf2, and the protection against chronic diseases. Given that there is a discrepancy between preclinical and clinical studies, approaches that may result in greater pharmacological and clinical success of low-molecular-weight antioxidant therapies are also subject to discussion.

Prenylated Flavonoids of the Moraceae Family: A Comprehensive Review of Their Biological Activities

Prenylated flavonoids (PFs) are natural flavonoids with a prenylated side chain attached to the flavonoid skeleton. They have great potential for biological activities such as anti-diabetic, anti-cancer, antimicrobial, antioxidant, anti-inflammatory, enzyme inhibition, and anti-Alzheimer's effects. Medicinal chemists have recently paid increasing attention to PFs, which have become vital for developing new therapeutic agents. PFs have quickly developed through isolation and semi- or full synthesis, proving their high value in medicinal chemistry research. This review comprehensively summarizes the research progress of PFs, including natural PFs from the Moraceae family and their pharmacological activities. This information provides a basis for the selective design and optimization of multifunctional PF derivatives to treat multifactorial diseases.

Nutritive value, biological properties, health benefits and applications of Tetrapleura tetraptera: An updated comprehensive review

Due to the health benefits that medicinal plants present, they are applied in traditional healthcare in developing and developed countries alike. Tetrapleura tetraptera, a flowering plant mostly found in the western part of Africa has an essential chemical composition that gives it nutritive value and medicinal capacities. This review aims to highlight the nutritional attributes, biological properties, health benefits, and applications of T. tetraptera. The fruit of the plant has been revealed to possess about 58.48-63. 86% carbohydrates, 251.22-288.62 mg/g potassium, 182.11-200.02 mg/g calcium, 322.00-342.00 mg/g manganese, and 0.02-4.69 mg/g vitamins. Also, active phytochemical compounds including phenols (3.51 ± 0.03 mgGAE/g), flavonoids (0.87 ± 0.03 mgQE/g), saponins (4.27 ± 0.03 mgDE/g), tannins (23.87 ± 0.44 mg/100 g), and alkaloids (5.03 ± 0.15% w/w) have been discovered in the fruit of T. tetraptera. The plant's abundant phytochemicals account for its antioxidant, antimicrobial, anti-inflammatory, anti-diabetic, anti-parasitic, and anti-proliferative activities. These biological properties in turn translate to health benefits including lower blood pressure, enhanced immune system, malaria treatment, diabetes and hypertension management, and cancer prevention. The health-promoting assets of T. tetraptera underscore its applications in beverage production, food preservation and flavoring, feed supplementation, and pharmaceutical formulations. The data gathered in this piece is crucial for industrial food processing and the creation of potent pharmaceutical products and functional foods with superior health attributes.

A comparative study of secondary metabolites profiling and biological activity of Smyrnium olusatrum L. leaf, flower and fruit

Essential oil (EO) composition of Smyrnium olusatrum was characterised by high proportion of furanosesquiterpenes (51.66-69.35%). The leaf methanolic extract composition was found to be rich with Quercetin-O-hexoside (39.78%). Apigenin 6,8-di-Chexoside represent the major component of flower (18.2%) and fruits (18.82%). Flower extract exhibited the highest contents of total phenolic (48.97 mg GAE/g) and flavonoid (52.63 mg RE/g). The β-carotene and lycopene contents were in the order of 4.55-26.14 mg/100g, and 8.00-49.45 mg/100g, respectively. Methanolic extracts and EOs of different organs were found to possess antioxidant activities, as determined by scavenging effect, chelating activity and β-carotene-linoleic acid model system. Furthermore, Fruit S. olusatrum EO exhibited a potent inhibitory activity against Acetylcholinesterase, while the methanolic extract showed a weaker activity. The methanolic extract displayed inhibitory effects on α-amylase, whereas the EOs was not as efficient in inhibiting this enzyme. The observed level of biological activities varied depending on the specific extracts and organs studied.

Determination of In Vitro and In Vivo Effects of Taxifolin and Epirubicin on Epithelial-Mesenchymal Transition in Mouse Breast Cancer Cells

Background: One of the most significant characteristics of cancer is epithelial-mesenchymal transition and research on the relationship between phenolic compounds and anticancer medications and epithelial-mesenchymal transition is widespread. Methods: In order to investigate the potential effects of Taxifolin on enhancing the effectiveness of Epirubicin in treating breast cancer, specifically in 4T1 cells and an allograft BALB/c model, the effects of Taxifolin and Epirubicin, both individually and in combination, were examined. Cell viability assays and cytotoxicity assays in 4T1 cells were performed. In addition, 4T1 cells were implanted into female BALB/c mice to conduct in vivo studies and evaluate the therapeutic efficacy of Taxifolin and Epirubicin alone or in combination. Tumor volumes and histological analysis were also assessed in mice. To further understand the mechanisms involved, we examined the messenger RNA and protein levels of epithelial-mesenchymal transition-related genes, as well as active Caspase-3/7 levels, using quantitative real-time polymerase chain reaction, western blot, and enzyme-linked immunosorbent assays, respectively. Results: In vitro results demonstrated that the coadministration of Taxifolin and Epirubicin reduced cell viability and cytotoxicity in 4T1 cell lines. In vivo, coadministration of Taxifolin and Epirubicin suppressed tumor growth in BALB/c mice with 4T1 breast cancer cells. Additionally, this combination treatment significantly increased the levels of active caspase-3/7 and downregulated the messenger RNA and protein levels of N-cadherin, β-catenin, vimentin, snail, and slug, but upregulated the E-cadherin gene. It significantly decreased the messenger RNA levels of the Zeb1 and Zeb2 genes. Conclusion: The in vitro and in vivo results of our study indicate that the concurrent use of Epirubicin with Taxifolin has supportive effects on breast cancer treatment.

Tryptophan Metabolism and Gut Microbiota: A Novel Regulatory Axis Integrating the Microbiome, Immunity, and Cancer

Tryptophan metabolism and gut microbiota form an integrated regulatory axis that impacts immunity, metabolism, and cancer. This review consolidated current knowledge on the bidirectional interactions between microbial tryptophan processing and the host. We focused on how the gut microbiome controls tryptophan breakdown via the indole, kynurenine, and serotonin pathways. Dysbiosis of the gut microbiota induces disruptions in tryptophan catabolism which contribute to disorders like inflammatory conditions, neuropsychiatric diseases, metabolic syndromes, and cancer. These disruptions affect immune homeostasis, neurotransmission, and gut-brain communication. Elucidating the mechanisms of microbial tryptophan modulation could enable novel therapeutic approaches like psychobiotics and microbiome-targeted dietary interventions. Overall, further research on the microbiota-tryptophan axis has the potential to revolutionize personalized diagnostics and treatments for improving human health.

Nutrient-Based Approaches for Melanoma: Prevention and Therapeutic Insights

Melanoma, a prevalent and lethal form of skin cancer, remains a formidable challenge in terms of prevention and treatment. While significant progress has been made in understanding its pathogenesis and treatment, the quest for effective prevention strategies and therapeutic approaches remains ongoing. Considering the increased advancements in understanding the dynamic interplay between nutrients and melanoma, we aim to offer a refreshed perspective on nutrient-based approaches for melanoma prevention and adjunctive therapy. In contrast to other studies, we have innovatively provided a detailed exposition of the nutrients' influences on melanoma prognosis and treatment. This review firstly examines various nutrients, including antioxidants (namely vitamins A, D, C, and E; selenium; and caffeine), polyunsaturated fatty acids, and flavonoids, for their effects and underlying mechanisms in reducing melanoma risk. Among these nutrients, caffeine shows the most promising potential, as it is supported by multiple cohort studies for its protective effect against melanoma. In contrast, there is a certain degree of inconsistency in the research of other nutrients, possibly due to inherent differences between animal studies and epidemiological research, as well as variations in the definition of nutrient intake. To comprehensively investigate the impact of nutrients on melanoma progression and therapeutic approaches, the following sections will explore how nutrients influence immune responses and other physiological processes. While there is robust support from cell and animal studies regarding the immunomodulatory attributes of vitamins D and zinc, the anti-angiogenic potential of polyphenols, and the cell growth-inhibitory effects of flavonoids, the limited availability of human-based research substantially constrains their practical relevance in clinical contexts. As for utilizing nutrients in adjuvant melanoma treatments, multiple approaches have garnered clinical research support, including the utilization of vitamin D to decrease the postoperative recurrence rates among melanoma patients and the adoption of a high-fiber diet to enhance the effectiveness of immunotherapy. In general, the effects of most nutrients on reducing the risk of melanoma are not entirely clear. However, several nutrients, including vitamin D and dietary fiber, have demonstrated their potential to improve the melanoma prognosis and enhance the treatment outcomes, making them particularly deserving of clinical attention. A personalized and interdisciplinary approach, involving dermatologists, oncologists, nutritionists, and researchers, holds the promise of optimizing melanoma treatment strategies.

Phloridzin Docosahexaenoate Inhibits Spheroid Formation by Breast Cancer Stem Cells and Exhibits Cytotoxic Effects against Paclitaxel-Resistant Triple Negative Breast Cancer Cells

The eradication of cancer stem cells (CSCs) is vital to successful cancer treatment and overall disease-free survival. CSCs are a sub-population of cells within a tumor that are defined by their capacity for continuous self-renewal and recapitulation of new tumors, demonstrated in vitro through spheroid formation. Flavonoids are a group of phytochemicals with potent anti-oxidant and anti-cancer properties. This paper explores the impact of the flavonoid precursor phloridzin (PZ) linked to the ω-3 fatty acid docosahexaenoate (DHA) on the growth of MCF-7 and paclitaxel-resistant MDA-MB-231-TXL breast cancer cell lines. Spheroid formation assays, acid phosphatase assays, and Western blotting were performed using MCF-7 cells, and the cell viability assays, Annexin-V-488/propidium iodide (PI) staining, and 7-aminoactinomycin D (7-AAD) assays were performed using MDA-MB-231-TXL cells. PZ-DHA significantly reduced spheroid formation, as well as the metabolic activity of MCF-7 breast cancer cells in vitro. Treatment with PZ-DHA also suppressed the metabolic activity of MDA-MB-231-TXL cells and led to apoptosis. PZ-DHA did not have an observable effect on the expression of the drug efflux transporters ATP-binding cassette super-family G member 2 (ABCG2) and multidrug resistance-associated protein 1 (MRP1). PZ-DHA is a potential treatment avenue for chemo-resistant breast cancer and a possible novel CSC therapy. Future pre-clinical studies should explore PZ-DHA as a chemo-preventative agent.

Baicalein Induces G2/M Cell Cycle Arrest Associated with ROS Generation and CHK2 Activation in Highly Invasive Human Ovarian Cancer Cells

Ovarian cancer is a lethal gynecological cancer because drug resistance often results in treatment failure. The CHK2, a tumor suppressor, is considered to be an important molecular target in ovarian cancer due to its role in DNA repair. Dysfunctional CHK2 impairs DNA damage-induced checkpoints, reduces apoptosis, and confers resistance to chemotherapeutic drugs and radiation therapy in ovarian cancer cells. This provides a basis for finding new effective agents targeting CHK2 upregulation or activation to treat or prevent the progression of advanced ovarian cancer. Here, the results show that baicalein (5,6,7-trihydroxyflavone) treatment inhibits the growth of highly invasive ovarian cancer cells, and that baicalein-induced growth inhibition is mediated by the cell cycle arrest in the G₂/M phase. Baicalein-induced G₂/M phase arrest is associated with an increased reactive oxygen species (ROS) production, DNA damage, and CHK2 upregulation and activation. Thus, baicalein modulates the expression of DNA damage response proteins and G₂/M phase regulatory molecules. Blockade of CHK2 activation by CHK2 inhibitors protects cells from baicalein-mediated G₂/M cell cycle arrest. All the results suggest that baicalein has another novel growth inhibitory effect on highly invasive ovarian cancer cells, which is partly related to G₂/M cell cycle arrest through the ROS-mediated DNA breakage damage and CHK2 activation. Collectively, our findings provide a molecular basis for the potential of baicalein as an adjuvant therapeutic agent in the treatment of metastatic ovarian cancer.

Preparation of rutin-loaded mesoporous silica nanoparticles and evaluation of its physicochemical, anticancer, and antibacterial properties

BACKGROUND

The studies have shown that rutin has great potential as an anticancer and antimicrobial plant base agent; nevertheless, poor bioavailability and low aqueous solubility of rutin limit its application. One of the beneficial routes to increase the solubility and bioavailability of rutin is the development of nanoparticulate material. This study aimed to assess the anticancer and antibacterial effects of rutin-loaded mesoporous silica nanoparticles (RUT-MSNs).

METHODS

RUT-MSNs were prepared and physicochemically characterized. The cytotoxicity of RUT-MSNs on the HN5 cells as head and neck cancer cells was evaluated. The expression level of apoptosis-related genes such as Bcl-2 and Bax genes were evaluated. In addition, ROS production of RUT-MSNs treated cells was assessed. In addition, minimum inhibitory concentration (MIC), biofilm, and attachment inhibitory effects of RUT-MSNs compared with free rutin were assessed against different bacterial strains.

RESULTS

Transmission electron microscopy (TEM) showed mesoporous rod-shaped nanoparticles with an average particle size of less than 100 nm. RUT-MSNs displayed the cytotoxic effect with IC₅₀ of 20.23 µM in 48 h of incubation time (p < 0.05). The elevation in the ratio of Bax/Bcl-2 was displayed within the IC₅₀ concentration of RUT-MSNs in 48 h (p < 0.05). The antibacterial action of rutin was improved by loading rutin in MSNs to the nano-sized range in the MIC test.

CONCLUSION

The anticancer and antibacterial effects of RUT-MSNs were considerably more than rutin. RUT-MSNs inhibited the growth of HN5 cells by inducing apoptosis and producing ROS. These results suggest that RUT-MSNs may be useful in the treatment of cancers and infections.

Cerium improves the physiology and medicinal components of Dendrobium nobile Lindl. under copper stress

Heavy metal stress affects the quality of medicinal plants, and rare earth elements can effectively alleviate heavy metal stress. In this paper, we investigated the effects of rare earth element cerium (0, 5, 10, 20, 40, 80, and 160 mg/L) on the physiological and medicinal components of Dendrobium nobile Lindl. under copper (200 mg/L) stress. The results revealed that cerium (Ce) had a good alleviating effect on copper (Cu) stress, low concentrations of Ce (10-20 mg/L) significantly improved the resistance and medicinal qualities of the plant such as polysaccharide, polyphenol and flavonoid, it also increased the content of photosynthetic pigment, proline, soluble sugar and soluble protein of D. nobile Lindl., effectively balance the osmotic pressure and the generation and removal of reactive oxygen species in the plant, thereby the toxic effect of copper on D. nobile Lindl. is alleviated. From the point of view of the treatment time when the optimal relieving concentration appeared, the optimal concentration for relieving antioxidant enzyme activity all appeared at the treatment time of 10 d, the optimum concentrations of other indicators all appeared at the treatment time of 15 d. Overall, this study suggests that the optimum level of Ce (10-20 mg/L) might be promising for alleviating the adverse impacts of copper stress and promoting the accumulation of medicinal components in D. nobile Lindl.

Naringin and Naringenin Polyphenols in Neurological Diseases: Understandings from a Therapeutic Viewpoint

The glycosides of two flavonoids, naringin and naringenin, are found in various citrus fruits, bergamots, tomatoes, and other fruits. These phytochemicals are associated with multiple biological functions, including neuroprotective, antioxidant, anticancer, antiviral, antibacterial, anti-inflammatory, antiadipogenic, and cardioprotective effects. The higher glutathione/oxidized glutathione ratio in 3-NP-induced rats is attributed to the ability of naringin to reduce hydroxyl radical, hydroperoxide, and nitrite. However, although progress has been made in treating these diseases, there are still global concerns about how to obtain a solution. Thus, natural compounds can provide a promising strategy for treating many neurological conditions. Possible therapeutics for neurodegenerative disorders include naringin and naringenin polyphenols. New experimental evidence shows that these polyphenols exert a wide range of pharmacological activity; particular attention was paid to neurodegenerative diseases such as Alzheimer's and Parkinson's diseases, as well as other neurological conditions such as anxiety, depression, schizophrenia, and chronic hyperglycemic peripheral neuropathy. Several preliminary investigations have shown promising evidence of neuroprotection. The main objective of this review was to reflect on developments in understanding the molecular mechanisms underlying the development of naringin and naringenin as potential neuroprotective medications. Furthermore, the configuration relationships between naringin and naringenin are discussed, as well as their plant sources and extraction methods.

Antileukemic, Antioxidant, Anti-Inflammatory and Healing Activities Induced by a Polyphenol-Enriched Fraction Extracted from Leaves of Myrtus communis L

Natural products have offered a number of exciting approaches in cancer treatment over the years. In this study, we investigated the prophylactic and therapeutic effects of the polyphenol-enriched fraction extracted from Myrtus communis (PEMC) on acute and chronic leukemia. According to the UHPLC-MSⁿ, the fraction is rich in flavonoids. Protective activity of the PEMC was assessed by evaluating the antioxidant, anti-inflammatory, wound healing, and hemolysis potential in a series of in vivo and in vitro assays, while the therapeutic approach consisted of the evaluation of cytotoxic activity of the PEMC against HL60 and K562 leukemia cell lines. Safety of the fraction was also evaluated on a non-cancerous Vero cell line and by an acute toxicity test performed in mice. The PEMC demonstrated a significant anti-inflammatory and healing potential. The activities found at the dose of 100 mg/kg were better than those observed using a reference drug. The PEMC demonstrated a significant antioxidant effect and a specific cytotoxicity towards HL60 (IC₅₀ = 19.87 µM) and K562 (IC₅₀ = 29.64 µM) cell lines being non-toxic to the Vero cell line. No hemolytic activity was observed in vitro and no toxicity effect was found in mice. Thus, the PEMC has a pharmacological potential as both preventive and therapeutic agent. However, further research is necessary to propose its mechanism of action.

Flavonoids as regulators of TIMPs expression in cancer: Consequences, opportunities, and challenges

Cancer is one of the leading causes of death in patients worldwide, where invasion and metastasis are directly responsible for this statement. Although cancer therapy has progressed in recent years, current therapeutic approaches are ineffective due to toxicity and chemoresistance. Therefore, it is essential to evaluate other treatment options, and natural products are a promising alternative as they show antitumor properties in different study models. This review describes the regulation of tissue inhibitors of metalloproteinases (TIMPs) expression and the role of flavonoids as molecules with the antitumor activity that targets TIMPs therapeutically. These inhibitors regulate tissue extracellular matrix (ECM) turnover; they inhibit matrix metalloproteinases (MMPs), cell migration, invasion, and angiogenesis and induce apoptosis in tumor cells. Data obtained in cell lines and in vivo models suggest that flavonoids are chemopreventive and cytotoxic against various types of cancer through several mechanisms. Flavonoids also regulate crucial signaling pathways such as focal adhesion kinase (FAK), phosphatidylinositol-3-kinase (PI3K)-Akt, signal transducer and activator of transcription 3 (STAT3), nuclear factor κB (NFκB), and mitogen-activated protein kinase (MAPK) involved in cancer cell migration, invasion, and metastasis. All these data reposition flavonoids as excellent candidates for use in cancer therapy.

Crystal structure of 3,5,6,7-tetramethoxy-3′,4′-methylenedioxy-flavone, C20H18O8

C20H18O8, monoclinic, P21/c (no. 14), a = 7.3855(2) Å, b = 28.1424(9) Å, c = 8.5863(3) Å, β = 98.4040(10)°, V = 1765.46(10) Å3, Z = 4, R gt (F) = 0.0545, wR ref (F 2) = 0.1641, T = 273(2) K.

Diet, Microbes, and Cancer Across the Tree of Life: a Systematic Review

PURPOSE OF REVIEW

Cancers are a leading cause of death in humans and for many other species. Diet has often been associated with cancers, and the microbiome is an essential mediator between diet and cancers. Here, we review the work on cancer and the microbiome across species to search for broad patterns of susceptibility associated with different microbial species.

RECENT FINDINGS

Some microbes, such as Helicobacter bacteria, papillomaviruses, and the carnivore-associated Fusobacteria, consistently induce tumorigenesis in humans and other species. Other microbes, such as the milk-associated Lactobacillus, consistently inhibit tumorigenesis in humans and other species. We systematically reviewed over a thousand published articles and identified links between diet, microbes, and cancers in several species of mammals, birds, and flies. Future work should examine a larger variety of host species to discover new model organisms for human preclinical trials, to better understand the observed variance in cancer prevalence across species, and to discover which microbes and diets are associated with cancers across species. Ultimately, this could help identify microbial and dietary interventions to diagnose, prevent, and treat cancers in humans as well as other animals.

Evaluation of the cytotoxic, anticancer, and genotoxic activities of Acacia nilotica flowers and their effects on N-methyl-N-nitrosourea-induced genotoxicity in mice

Purpose

In this study, two main research objectives were examined: (1) the cytotoxic and anticancer activities of the aqueous methanol extract from Acacia nilotica flowers on three human cancer cells, namely lung A549, breast MCF-7, and leukemia THP-1 cells, and (2) the genotoxic effects of A. nilotica extract and its influence on DNA damage induced by N-methyl-N-nitrosourea (MNU) in mice.

Methods

Mice were orally treated with A. nilotica extract (200, 500, and 800 mg/kg for 4 days) with or without MNU (80 mg/kg intraperitoneally for 24 h).

Results

In vitro experiments showed that A549 cells were the most sensitive to A. nilotica extract among the tested cell lines. A. nilotica extract inhibited A549 cell proliferation by blocking the cell cycle at the G₂/M phase and accumulating apoptotic cells in the sub-G₀/G₁ phase in A549 cells. In vivo experiments showed that MNU induced positive and negative genotoxicity in bone marrow cells and spermatocytes, respectively. Negative genotoxicity was observed in A. nilotica extract-treated groups only. However, A. nilotica extract (800 mg/kg) remarkably increased comet tail formation in bone marrow cells. Unexpectedly, the absence of antigenotoxicity was observed in three cotreated groups with A. nilotica extract and MNU compared with the MNU-treated group. Astonishingly, cotreatment with MNU and A. nilotica extract at a dose above 200 mg/kg remarkably increased micronucleus and comet tail formation in bone marrow cells compared with the MNU-treated group.

Conclusions

A. nilotica extract possessed anticancer activity with relative genotoxic effects at high doses.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11033-022-07662-0.

Subchronic Toxicity Study of Alternanthera philoxeroides in Swiss Albino Mice Having Antioxidant and Anticoagulant Activities

Alternanthera philoxeroides, a tropical herb and edible vegetable, has been popular as a medicinal plant. Applying in vitro approach, we initially attempted to assess the phytochemicals, bioactive chemicals, as well as antioxidant and anticoagulant activities of this plant. Following that, the in vivo toxicological effects of methanolic extracts of A. philoxeroides using different doses on the kidney, heart, lung, liver, stomach, brain, and blood of female Swiss Albino mice were investigated. We estimated phytochemicals content as well as antioxidant activity through DPPH, NO, CUPRAC, and reducing power assays, followed by the anticoagulant activities of PT  and aPTT  and bioactive compounds using HPLC. To confirm the biocompatibility of A. philoxeroides extracts, histopathological and hematological parameters were examined in a mice model. Total phenol, flavonoid, and tannin content in A. philoxeroides was 181.75 ± 2.47 mg/g, 101.5 ± 3 .53 mg/g, and 68.58 ± 0.80 mg/g, respectively. Furthermore, the HPLC study confirmed the presence of four phenolic compounds: catechin, tannic acid, gallic acid, and vanillic acid. The methanolic extract of A. philoxeroides showed considerable antioxidant activity in all four antioxidant assay methods when compared to the standard. In comparison to ascorbic acid, A. philoxeroides also demonstrated a minor concentration-dependent ferric and cupric reduction activity. In vivo evaluation indicated that A. philoxeroides extracts (doses: 250, 500, and 1000 mg/kg) had no negative effects on the relative organ or body weight, or hematological indicators. Our study concluded that A. philoxeroides had significant antioxidant and anticoagulant activities and demonstrated no negative effects on the body or relative organ weight, histopathological, and hematological indices in the mouse model.

In vitro anticancer properties of anthocyanins: A systematic review

Anthocyanins have been associated with beneficial effects on human health. Cancer has been one of the main public health issues due to its aggressiveness and high mortality rate. This systematic review aimed to address recent research (from January 2000 to September 2021) on the anticancer activity of anthocyanins assessed by in vitro assays. The selected studies revealed that anthocyanins have anticancer potential by inhibiting cancer cell viability and proliferation, controlling cell cycle, and promoting apoptosis.

Prospective multifunctional roles and pharmacological potential of dietary flavonoid narirutin

Plant-based phytochemicals are now being used to treat plenty of physiological diseases. Herbal drugs have gained popularity in recent years because of their strength, purity, and cheap cost-effectiveness. Citrus fruits contain significant amounts of flavanones, which falls to the category of polyphenols. Flavanones occupy a major fraction of the total polyphenols present in the plasma when orange juice is taken highly or in moderate states. Narirutin is a disaccharide derivative available in citrus fruits, primarily dihydroxy flavanone. From a pharmacological viewpoint, narirutin is a bioactive phytochemical with therapeutic efficacy. Many experimental researches were published on the use of narirutin. Anticancer activity, neuroprotection, stress relief, hepatoprotection, anti-allergic activity, antidiabetic activity, anti-adipogenic activity, anti-obesity action, and immunomodulation are a couple of the primary pharmacological properties. Narirutin also has antioxidant, and anti-inflammatory activities. The ultimate goal of this review is to provide the current scenario of pharmacological research with narirutin; to make a better understanding for therapeutic potential of narirutin, as well as its biosynthesis strategies and side effects. Extensive literature searches and studies were undertaken to determine the pharmacological properties of narirutin.

Antioxidant Activity and Multi-Elemental Analysis of Dark Chocolate

Cocoa beans are part of the cocoa plant fruit (Theobroma cacao L.) used to prepare various products such as chocolate, cocoa butter, jelly, liqueurs, cosmetics, etc. Dark chocolate is consumed worldwide by different populations and is known for its good taste, making it one of the most favoured food products. This work aimed to determine the content of total polyphenols (TPC), total flavonoids (TFC), and the antioxidant potential measured through the ability to scavenge DPPH free radicals (DPPH), ferric reducing power (FRAP), and total antioxidant capacity (TAC), as well as major and trace elements contained in twelve commercially available dark chocolate samples, with cocoa content ranging from 40% to 99%. The total polyphenols content ranged between 10.55 and 39.82 mg/g GAE, while the total flavonoid content was from 10.04 to 37.85 mg/g CE. All applied antioxidant assays indicate that the sample with the highest cocoa percentage shows the greatest antioxidant activity (DPPH: 48.34% of inhibition; FRAP: 89.00 mg/g GAE; TAC: 83.86 mg/g AAE). Statistical methods were applied to establish the differences between the samples concerning TPC, TFC, DPPH, FRAP and TAC, as well as to differentiate the samples according to the mineral content. The results indicated that the differences in TPC and TFC between different samples depended on the cocoa content and the addition of dried fruit pieces. A good correlation between antioxidant potency composite index (ACI) and declared cocoa content was noticed (R² = 0.8034), indicating that the declared percentage of cocoa is a reliable indicator for antioxidant activity of analysed dark chocolate samples. The nutritional evaluation proved that the studied chocolate samples were an excellent source of Mg, Fe, Mn and Cu.

Boronate affinity-based template-immobilization surface imprinted quantum dots as fluorescent nanosensors for selective and sensitive detection of myricetin

In order to prepare a kind of efficient fluorescence sensors for determination of cis-diol-containing flavonoids, novel imprinted quantum dots for myricetin (Myr) were prepared based on boronate affinity-based template-immobilization surface imprinting. The obtained boronate affinity-based surface imprinted silica (imprinted APBA-functionalized CdTe QDs) was used as recognition elements. The quantum dots were used as signal-transduction materials. Under the optimum conditions, according to fluorescence quenching of imprinted APBA-functionalized CdTe QDs by Myr, the imprinting factor (IF) for Myr was evaluated to be 7.88. The result indicated that the boronate affinity functionalized quantum dots coated with imprinted silica were successfully prepared. The prepared imprinted APBA-functionalized CdTe QDs exhibited good sensitivity and selectivity for Myr. The fluorescence intensity was inversely proportional to the concentration of Myr in the 0.30-40 μM concentration range. And its detection limit was obtained to be 0.08 μM. Using the fluorescence sensors, the detection of Myr in real samples was successfully carried out, and the concentration of Myr in green tea and apple juice samples was evaluated to be 2.26 mg/g and 0.73 mg/g, respectively. The recoveries for the spiked green tea and apple juice samples were 95.2-105.0% and 91.5-111.0%, respectively. This study also provides an efficient fluorescent detection method for cis-diol-containing flavonoids in real samples.

Microbiome in cancer: Role in carcinogenesis and impact in therapeutic strategies

Cancer is the world's second-leading cause of death, and the involvement of microbes in a range of diseases, including cancer, is well established. The gut microbiota is known to play an important role in the host's health and physiology. The gut microbiota and its metabolites may activate immunological and cellular pathways that kill invading pathogens and initiate a cancer-fighting immune response. Cancer is a multiplex illness, characterized by the persistence of several genetic and physiological anomalies in malignant tissue, complicating disease therapy and control. Humans have coevolved with a complex bacterial, fungal, and viral microbiome over millions of years. Specific long-known epidemiological links between certain bacteria and cancer have recently been grasped at the molecular level. Similarly, advances in next-generation sequencing technology have enabled detailed research of microbiomes, such as the human gut microbiome, allowing for the finding of taxonomic and metabolomic linkages between the microbiome and cancer. These investigations have found causative pathways for both microorganisms within tumors and bacteria in various host habitats far from tumors using direct and immunological procedures. Anticancer diagnostic and therapeutic solutions could be developed using this review to tackle the threat of anti-cancer medication resistance as well through the wide-ranging involvement of the microbiota in regulating host metabolic and immunological homeostasis. We reviewed the significance of gut microbiota in cancer initiation as well as cancer prevention. We look at certain microorganisms that may play a role in the development of cancer. Several bacteria with probiotic qualities may be employed as bio-therapeutic agents to re-establish the microbial population and trigger a strong immune response to remove malignancies, and further study into this should be conducted.

Variation in Population and Solvents as Factors Determining the Chemical Composition and Antioxidant Potential of Arctostaphylos uva-ursi (L.) Spreng. Leaf Extracts

The bearberry Arctostaphylos uva-ursi (L.) Spreng. has a long history of ethnopharmacological use. This species has been used in folk medicine for centuries as a rich source of raw material abundant in secondary metabolites and is important for medicinal and pharmacological purposes. The plant is a source of herbal material—Uvae ursi folium, which is highly valued and sought by pharmaceutical and cosmetic industries. The studied bearberry leaves can be classified as a suitable herbal material for use in pharmacy; therefore, the investigated populations can be a potentially valuable source of plant material for cultivation and can be used in in vitro cultures and in biotechnological processes. The objective of this study was to characterize the variability of the phytochemical composition and antioxidant activity of water and ethanol bearberry extracts from raw material collected from different natural populations. In each of the twelve A. uva-ursi sites, three leaf samples were collected and analyzed. The water extracts from bearberry leaves were characterized by similar concentration of arbutin (77.64–105.56 mg g⁻¹) and a significantly higher concentration of hydroquinone (6.96–13.08 mg g⁻¹) and corilagin (0.83–2.12 mg g⁻¹) in comparison with the ethanol extracts −77.21–103.38 mg g⁻¹, 10.55–16.72 mg g⁻¹, 0.20–1.54 mg g⁻¹, respectively. The concentration of other metabolites in the water extracts was significantly lower in comparison with the ethanol extracts. In the case of the water extracts, a significant effect of not only total phenolic compounds, but also hydroquinone on the antioxidant parameters, was observed, which indicates the solvent-related activity of these metabolites. Therefore, it is suggested that special attention should be paid to the concentration of not only arbutin, but also hydroquinone in Uvae ursi folium. The latter metabolite serving a very important function as an active bearberry ingredient should be controlled not only in alcoholic extracts but also in water extracts, since bearberry leaves are applied as infusions and decoctions. The results presented in this paper can contribute to appropriate selection of plant material for pharmaceutical, cosmetic, and food industries, with special emphasis on the antioxidant activity of different types of extracts.

The Biphasic Effect of Flavonoids on Oxidative Stress and Cell Proliferation in Breast Cancer Cells

Flavonoids have been reported to play an essential role in modulating processes of cellular redox homeostasis such as scavenging ROS. Meanwhile, they also induce oxidative stress that exerts potent antitumor bioactivity. However, the contradiction between these two aspects still remains unclear. In this study, four typical flavonoids were selected and studied. The results showed that low-dose flavonoids slightly promoted the proliferation of breast cancer cells under normal growth via gradually reducing accumulated oxidative products and demonstrated a synergistic effect with reductants NAC or VC. Besides, low-dose flavonoids significantly reduced the content of ROS and MDA induced by LPS or Rosup but restored the activity of SOD. However, high-dose flavonoids markedly triggered the cell death via oxidative stress as evidenced by upregulated ROS, MDA and downregulated SOD activity that could be partly rescued by NAC pretreatment, which was also confirmed by antioxidative gene expression levels. The underlying mechanism of such induced cell death was pinpointed as apoptosis, cell cycle arrest, accumulated mitochondrial superoxide, impaired mitochondrial function and decreased ATP synthesis. Transcriptomic analysis of apigenin and quercetin uncovered that high-dose flavonoids activated TNF-α signaling, as verified through detecting inflammatory gene levels in breast cancer cells and RAW 264.7 macrophages. Moreover, we identified that BRCA1 overexpression effectively attenuated such oxidative stress, inflammation and inhibited ATP synthesis induced by LPS or high dose of flavonoids possibly through repairing DNA damage, revealing an indispensable biological function of BRCA1 in resisting oxidative damage and inflammatory stimulation caused by exogenous factors.

Quercetin- and rutin-based nano-formulations for cancer treatment: A systematic review of improved efficacy and molecular mechanisms

BACKGROUND

Natural products, with incredible chemical diversity, have been widely studied for their antitumor potential. Quercetin (QU) and quercetin glycoside (rutin), both polyphenolic flavonoids, stick out amongst the natural products, through various studies. Rutin (RU) and its aglycone (QU) have various biological properties that include antioxidant, anti-inflammatory, and anticarcinogenic activities. However, several side effects have restricted the efficacy of these polyphenolic flavonoids, which makes it necessary to use new strategies involving low and pharmacological doses of QU and RU, either alone or in combination with other anticancer drugs.

PURPOSE

The aim of this study is to present a comprehensive and critical evaluation of the anticancer ability of different nano-formulations of RU and QU for improved treatment of various malignancies.

METHODS

Studies were recognized via systematic searches of ScienceDirect, PubMed, and Scopus databases. Eligibility checks were conducted based upon predefined selection criteria. Ninety articles were included in this study.

RESULTS

There was conclusive evidence for the association between anticancer activity and treatment with RU or QU. Furthermore, studies indicated that nano-formulations of RU and QU have greater anticancer activities in comparison to either agent alone, which leads to increased efficiency for treating cancer.

CONCLUSION

The results of this systematic review demonstrate the anticancer activities of nano-formulations of RU and QU and their molecular mechanisms through preclinical studies. This paper also attempts to contribute to further research by addressing the current limitations/challenges and proposing additional studies to realize the full potential of RU- and QU-based formulations for cancer treatment.

The Potential Role of Nutrition in Lung Cancer Establishment and Progression

Lung cancer is a devastating disease with a high incidence and low survival rates, so recent studies have focused on analyzing the risk factors that might prevent this disease from developing or have protective/therapeutic effects. Nutrition is an important key factor in the prevention and treatment of lung cancer. Various factors appear to be involved in the development of the latter, such as cigarette smoking or certain external environmental factors. The increase in oxidative stress is therefore an integral part of the carcinogenesis process. The biological role of bioactive factors derived from adipose tissue, mainly adipokines, is implicated in various cancers, and an increasing body of evidence has shown that certain adipocytokines contribute to the development, progression and prognosis of lung cancer. Not all adipokines stimulate tumor growth; in fact, adiponectin inhibits carcinogenesis by regulating both cell growth and the levels of inflammatory cytokines. Adiponectin expression is deregulated in several cancer types. Many nutritional factors have been shown to increase adiponectin levels and therefore could be used as a new therapeutic strategy for combating lung cancer. In addition, foods with antioxidant and anti-inflammatory properties play a key role in the prevention of many human diseases, including lung cancer. The purpose of this review is to analyze the role of diet in lung cancer in order to recommend dietary habit and lifestyle changes to prevent or treat this pathology.

Highly efficient separation and enrichment of polyphenols by 6-aminopyridine-3-boronic acid-functionalized magnetic nanoparticles assisted by polyethylenimine

Polyphenols have found a lot of therapeutic effects and potential applications such as antioxidant, anti-inflammatory, mutant resistance, immunosuppressant and anti-tumor properties. They can be divided into five main classes, namely flavonoids, phenolic acids, stilbenes, lignans, and others. Thus, the content detection of polyphenols in real samples such as fruit juice and tea is of great significance. Due to the presence of complex interfering components in actual samples, separation and enrichment of polyphenols prior to analysis is key. Therefore, it is quite necessary to establish a simple, low-cost and efficient purification method for cis-diol-containing polyphenols from real samples. Boronate affinity materials are able to reversibly bind cis-diol-containing compounds by forming a five- or six-membered boronic cyclic ester in aqueous media. However, conventional boronate affinity materials exhibited low binding capacity and high binding pH. In this study, the polyethyleneimine (PEI)-assisted 6-aminopyridine-3-boronic acid functionalized magnetic nanoparticles (MNPs) were developed to capture efficiently cis-diol-containing polyphenols under neutral condition. PEI was applied as a scaffold to amplify the number of boronic acid moieties. While 6-aminopyridine-3-boronic acid was used as an affinity ligand due to low pK_a value and excellent water solubility toward polyphenols. The results indicated that the prepared boronic acid-functionalized MNPs provided high binding capacity and fast binding kinetics under neutral conditions. In addition, the obtained MNPs exhibited relatively high binding affinity (K_d ≈ 10⁻⁴ M), low binding pH (pH ≥ 6.0) and tolerance of the interference of abundant sugars.

Synthesis routes of 6-aminopyridine-3-boronic acid-functionalized magnetic nanoparticles assisted by polyethylenimine (Fe₃O₄@PEI@PYBA).

Effect of Ultrasound-Assisted Pretreatment on Extraction Efficiency of Essential Oil and Bioactive Compounds from Citrus Waste By-Products

Waste or by-product use is in focus for reducing the environmental threat and acquiring wealth out of waste. The current study aim was to investigate the effects of ultrasound pretreatment on the extraction of bioactive compounds and composition of essential oils extracted from citrus waste. The response surface methodology (RSM) was used to optimize higher yield extraction parameters. Pretreatment of ultrasound-assisted extraction recovered 33% enhanced yield with reduced time and was economical as compared to conventional hydro-distilled process. The functional quality of essential oil was determined using FTIR and GC-MS. Antioxidants from citrus peel and pulp/pomace were extracted and analyzed by spectroscopic techniques. The quantification of bioactive compounds from citrus waste was performed using high performance liquid chromatography (HPLC). Mass transfer rate of antioxidants from peel and pomace were 30% increased as a result of ultrasound-assisted treatment. The significantly (p ≤ 0.05) higher TPC (735.54 mg/100 g) and antioxidant activity (44.26%) was recorded in Citrus sinensis Pulp and peel respectively. The bioactive compounds such as hesperidin (31.52 mg/100 g) was significantly higher in (p ≤ 0.05) in Citrus sinensis pulnd extract. Vanillin was found 1.21 mg/100 g in peel extract of citrus fruit, moreover vanillin was not detected in pulp extract. Myrecitin was not detected in both the samples. The bioactive natural compounds extracted from citrus peel can be used in food and pharma sector as natural anti-oxidantcompounds.

Assessment of the phytochemical profile and antioxidant activities of eight kiwi berry (Actinidia arguta (Siebold & Zuccarini) Miquel) varieties in China

The kiwi berry (Actinidia arguta) is a new product on the market that expanding worldwide acceptance and consumption. This widespread interest has created an increasing demand to identify the nutritional and health benefits of kiwi berry. Many studies are being actively conducted to investigate the composition and health-promoting effects of kiwi berry. In this study, the phytochemical content of free and bound fractions of eight kiwi berry varieties were systematically investigated in order to better understand the potential of this superfood crop. Nine phenolic monomers were identified and quantified by ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry and ultrahigh-performance liquid chromatography-PAD. Antioxidant activity was further determined via peroxyl radical scavenging capacity and cellular antioxidant activity assays. The free extracts had higher phytochemical contents and antioxidant activities than the corresponding bound extracts among the eight kiwi berry varieties. Bivariate Pearson's and multivariate correlation analyses showed that antioxidant activities were most related to the total phenolic, flavonoid, vitamin C, and phenolic acids contents. The results provide a theoretical basis for the selection of kiwi berry varieties and the utilization of functional foods.

Multifaceted antiviral therapeutic potential of dietary flavonoids: Emerging trends and future perspectives

Phytochemicals are the natural biomolecules produced by plants via primary or secondary metabolism, which have been known to have many potential health benefits to human beings. Flavonoids or phytoestrogens constitute a major group of such phytochemicals widely available in variety of vegetables, fruits, herbs, tea, and so forth, implicated in a variety of bio-pharmacological and biochemical activities against diseases including bacterial, viral, cancer, inflammatory, and autoimmune disorders. More recently, these natural biomolecules have been shown to have effective antiviral properties via therapeutically active ingredients within them, acting at different stages of infection. Current review emphasizes upon the role of these flavonoids in physiological functions, prevention and treatment of viral diseases. More so the review focuses specifically upon the antiviral effects exhibited by these natural biomolecules against RNA viruses including coronaviruses. Furthermore, the article would certainly provide a lead to the scientific community for the effective therapeutic antiviral use of flavonoids using potential cost-effective tools for improvement of the pharmacokinetics, bioavailability, and biodistribution of such compounds for the concrete action along with the promotion of human health.

Diosmin Inhibits Glioblastoma Growth through Inhibition of Autophagic Flux

Diosmin, a natural flavone glycoside acquired through dehydrogenation of the analogous flavanone glycoside hesperidin, is plentiful in many citrus fruits. Glioblastoma multiforme (GBM) is the most malignant primary brain tumor; the average survival time of GBM patients is less than 18 months after standard treatment. The present study demonstrated that diosmin, which is able to cross the blood-brain barrier, inhibited GBM cell growth in vitro and in vivo. Diosmin also impeded migration and invasion by GBM8401and LN229 GBM cells by suppressing epithelial-mesenchymal transition, as indicated by increased expression of E-cadherin and decreased expression of Snail and Twist. Diosmin also suppressed autophagic flux, as indicated by increased expression of LC3-II and p62, and induced cell cycle arrest at G1 phase. Importantly, diosmin did not exert serious cytotoxic effects toward control SVG-p12 astrocytes, though it did reduce astrocyte viability at high concentrations. These findings provide potentially helpful support to the development of new therapies for the treatment of GBM.

Role of microRNAs in the anticancer effects of the flavonoid luteolin: a systematic review

Flavonoids, a broad class of polyphenolic compounds, can potentially have several therapeutic properties in human diseases, including protective effects against oxidative stress, inflammation, cardiovascular disease, diabetes, neurodegenerative disorders, and cancers. Luteolin as a member of flavonoids has been found to exhibit several anticancer properties mainly through cell apoptosis induction, inhibition of invasion, cell proliferation, network formation, and migration. Recent studies have revealed that phytochemicals such as luteolin may exert therapeutic properties through microRNAs (miRNAs or miRs), which have been emerged as important molecules in cancer biology in recent years. miRNAs, as a class of noncoding RNAs, have several important roles in cancer progression or regression. In this review, we aimed to summarize and discuss the role of miRNAs in the luteolin effects on different cancers. This review can be in line with the studies, which have shown that miRNAs may be potential therapeutic targets in cancer treatment.

Enzymatic Metabolism of Flavonoids by Gut Microbiota and Its Impact on Gastrointestinal Cancer

Gastrointestinal (GI) cancer is a prevalent global health disease with a massive burden on health care providers. Internal and external factors such as obesity, smoking, diet (red meat), low socioeconomic status and infection with Helicobacter pylori are the critical risk factors of GI cancers. Flavonoids are natural phenolic compounds found abundantly in fruits and vegetables. Upon ingestion, 90% of flavonoids consumed require further enzymatic metabolism by the gut microbiome to enhance their bioavailability and absorption. Several epidemiological studies reported that consumption of flavonoids and their enzymatic conversion by gut microbes is strongly associated with the reduced risk of GI cancer development. This review summarizes the current knowledge on the enzymatic conversion of flavonoids by the human gut microbiome. It also addresses the underlying anti-GI cancer effects on metabolic pathways such as apoptosis and cellular proliferation. Overall, metabolites produced from flavonoid's enzymatic conversion illustrate anti-GI cancer effects, but the mechanisms of action need further clarification.

Bioactivity Studies of Hesperidin and XAV939

The present work aimed to evaluate the reactivity of natural bioflavonoid hesperidin (HSP) and synthetically derived XAV939 (XAV) against human hepatocellular carcinoma (HepG2), human breast cancer (MDA-MB231) cancer cell lines, and related molecular and pathological profiles. Data recorded revealed that the cytotoxic potential of the tested products was found to be cell type- and concentration-dependent. The half-maximal inhibitory concentration (IC₅₀) value of the HSP-XAV mixture against MDA-MB231 was significantly decreased in the case of using the HSP-XAV mixture against the HepG2 cell line. Also, there was a significant upregulation of the phosphotumor suppressor protein gene (P53) and proapoptotic genes such as B-cell lymphoma-associated X-protein (Bax, CK, and Caspase-3), while antiapoptotic gene B-cell lymphoma (Bcl-2) was significantly downregulated compared with the untreated cell control. The cell cycle analysis demonstrated that DNA accumulation was detected mainly during the G2/M phase of the cell cycle accompanied with the elevated reactive oxygen species level in the treatment of HepG2 and MDA-MB231 cell lines by the HSP-XAV mixture, more significantly than that in the case of cell control. Finally, our finding suggests that both HSP and XAV939 and their mixture may offer an alternative in human liver and breast cancer therapy.

Phenolics Profile and Antioxidant Activity Analysis of Kiwi Berry (Actinidia arguta) Flesh and Peel Extracts From Four Regions in China

The kiwi berry (Actinidia arguta) has been widely studied because of its rich phenolic, flavonoid, and vitamin C contents. Numerous reports have demonstrated that fruit peels contain higher phenolic content and antioxidant activity than that of flesh. In this study, the phytochemical content and antioxidant activities of peel and flesh extracts of six kiwi berries were analyzed from four regions (namely, Dandong, Benxi, Taian, and Tonghua) in China. The antioxidant activity was determined using the peroxyl radical scavenging capacity (PSC) and cellular antioxidant activity (CAA) assays. The phenolic, flavonoid, and vitamin C contents of kiwi berry peel were 10.77, 13.09, and 10.38 times richer than that of kiwi berry flesh, respectively. In addition, the PSC and CAA values of kiwi berry peel were higher than those of kiwi berry flesh. The analysis of the separation and contents of phenolics were performed by the high-performance liquid chromatography (HPLC)-diode-array detectormass spectrometry/mass (DAD-MS/MS) system, and the results illustrated that protocatechuic acid, caffeic acid, chlorogenic acid, and quinic acid were the major phenolic compounds. In conclusion, this study indicated that kiwi berry peel contains a rich source of antioxidants. These data are of great significance for the full development and utilization of kiwi berries in these four regions of China to produce nutraceutical and functional foods.

Safflower Extract Inhibits ADP-Induced Human Platelet Aggregation

Safflower extract is commonly used as a traditional Chinese medicine to promote blood circulation and remove blood stasis. The antioxidant and anticancer properties of safflower extracts have been extensively studied, but their antiaggregative effects have been less analyzed. We found that safflower extract inhibited human platelet aggregation induced by ADP. In addition, we further analyzed several safflower extract compounds, such as hydroxysafflor yellow A, safflower yellow A, and luteolin, which have the same antiaggregative effect. In addition to analyzing the active components of the safflower extract, we also analyzed their roles in the ADP signaling pathways. Safflower extract can affect the activation of downstream conductors of ADP receptors (such as the production of calcium ions and cAMP), thereby affecting the expression of activated glycoproteins on the platelet membrane and inhibiting platelet aggregation. According to the results of this study, the effect of safflower extract on promoting blood circulation and removing blood stasis may be related to its direct inhibition of platelet activation.

The protective effects of dietary intake of flavonoids and its subclasses on metabolic syndrome incidence

This study aimed to evaluate the association between the intake of total flavonoids and flavonoid subclasses and metabolic syndrome (MetS) risk and to assess the modulating effects of lifestyle factors on these associations. A total of 1915 participants from the Tehran Lipid and Glucose Study were followed-up during 2006-2008 and 2016-2018. Their dietary intake was assessed by a food frequency questionnaire at baseline and within three-year intervals afterward. Moreover, the modifying effect of weight gain on the association between total flavonoids and MetS was assessed by Cox regression analysis. Participants in the highest tertile of flavonoid, flavonol, and flavone had a significantly lower MetS risk as compared to those in the lowest tertile. Also, in participants with weight gain <7%, all flavonoid subclasses had a more pronounced risk-reducing effect. Overall, the total flavonoid, flavonol, and flavone reduced the risk of MetS; this association could be modified by weight gain.

Flavonoid-Based Cancer Therapy: An Updated Review

As cancers are one of the most important causes of human morbidity and mortality worldwide, researchers try to discover novel compounds and therapeutic approaches to decrease survival of cancer cells, angiogenesis, proliferation and metastasis. In the last decade, use of special phytochemical compounds and flavonoids was reported to be an interesting and hopeful tactic in the field of cancer therapy. Flavonoids are natural polyphenols found in plant, fruits, vegetables, teas and medicinal herbs. Based on reports, over 10,000 flavonoids have been detected and categorized into several subclasses, including flavonols, anthocyanins, flavanones, flavones, isoflavones and chalcones. It seems that the anticancer effect of flavonoids is mainly due to their antioxidant and anti inflammatory activities and their potential to modulate molecular targets and signaling pathways involved in cell survival, proliferation, differentiation, migration, angiogenesis and hormone activities. The main aim of this review is to evaluate the relationship between flavonoids consumption and cancer risk, and discuss the anti-cancer effects of these natural compounds in human cancer cells. Hence, we tried to collect and revise important recent in vivo and in vitro researches about the most effective flavonoids and their main mechanisms of action in various types of cancer cells.

The Potential Protective Effect of Orange Peel and Selenium against 17β-Estradiol- Induced Chronic Non-Bacterial Prostatitis in Rats

BACKGROUND

Prostate Cancer (PCa) is defined as a major health problem faced by the male population.

AIM

We aimed to investigate the protective effects of Orange Peel Extract (OPE) and/or Selenium (Se) on chronic non-bacterial prostatitis in a rat model.

METHODS

Fifty-six adult male Wistar albino rats were castrated; after 5 days, they were divided randomly into eight groups (n= 7). The control group received saline treatment; while 17β-estradiol (E2) (0.25mg/kg) was injected subcutaneously in rats from Groups V, VI, VII, and VIII to induce chronic non-bacterial prostatitis. They were then treated with OPE (400mg/kg body weight; Groups II, IV, VI, and VIII) and/or sodium selenite (0.5mg/kg body weight; Groups III, IV, VII, and VIII) for 30 days. Interleukin-2 (IL2) and Prostate Cancer Antigen 3 (PCA3) mRNA expressions were determined using qPCR; Prostate-Specific Antigen (PSA) protein expression was determined immunohistochemically. Prostate tissue histology was examined by hematoxylin and eosin staining, and the levels of oxidative stress markers and antioxidant enzymes were measured.

RESULTS

E2 administration significantly increased IL2 and PCA3 mRNA expressions, and PSA protein expression. It also increased the prostate wet weight and body weight, and lipid peroxidation, nitric oxide, TNF-α, and IL-1β levels, decreased the glutathione and antioxidant enzyme levels and caused distinct histological alterations in the prostate gland. OPE and/or Se markedly improved all the studied parameters due to their antioxidant properties and anti-inflammatory effects.

CONCLUSION

OPE and Se showed protective effects against 17β-estradiol-induced chronic non-bacterial prostatitis. These results suggest that protection of chronic non-bacterial prostatitis by OPE+Se combination involves anti-oxidation and anti-inflammation. Moreover, their synergistic mechanism was mostly achieved via the regulation of oxidative stress and inflammation processes.

Iridin Induces G2/M Phase Cell Cycle Arrest and Extrinsic Apoptotic Cell Death through PI3K/AKT Signaling Pathway in AGS Gastric Cancer Cells

Iridin is a natural flavonoid found in Belamcanda chinensis documented for its broad spectrum of biological activities like antioxidant, antitumor, and antiproliferative effects. In the present study, we have investigated the antitumor potential of iridin in AGS gastric cancer cells. Iridin treatment decreases AGS cell growth and promotes G2/M phase cell cycle arrest by attenuating the expression of Cdc25C, CDK1, and Cyclin B1 proteins. Iridin-treatment also triggered apoptotic cell death in AGS cells, which was verified by cleaved Caspase-3 (Cl- Caspase-3) and poly ADP-ribose polymerase (PARP) protein expression. Further apoptotic cell death was confirmed by increased apoptotic cell death fraction shown in allophycocyanin (APC)/Annexin V and propidium iodide staining. Iridin also increased the expression of extrinsic apoptotic pathway proteins like Fas, FasL, and cleaved Caspase-8 in AGS cells. On the contrary, iridin-treated AGS cells did not show variations in proteins related to an intrinsic apoptotic pathway such as Bax and Bcl-xL. Besides, Iridin showed inhibition of PI3K/AKT signaling pathways by downregulation of (p-PI3K, p-AKT) proteins in AGS cells. In conclusion, these data suggest that iridin has anticancer potential by inhibiting PI3K/AKT pathway. It could be a basis for further drug design in gastric cancer treatment.

Flavonoids increase melanin production and reduce proliferation, migration and invasion of melanoma cells by blocking endolysosomal/melanosomal TPC2

Two-pore channel 2 (TPC2) resides in endolysosomal membranes but also in lysosome-related organelles such as the melanin producing melanosomes. Gain-of-function polymorphisms in hTPC2 are associated with decreased melanin production and blond hair color. Vice versa genetic ablation of TPC2 increases melanin production. We show here an inverse correlation between melanin production and melanoma proliferation, migration, and invasion due to the dual activity of TPC2 in endolysosomes and melanosomes. Our results are supported by both genetic ablation and pharmacological inhibition of TPC2. Mechanistically, our data show that loss/block of TPC2 results in reduced protein levels of MITF, a major regulator of melanoma progression, but an increased activity of the melanin-generating enzyme tyrosinase. TPC2 inhibition thus provides a twofold benefit in melanoma prevention and treatment by increasing, through interference with tyrosinase activity, the synthesis of UV blocking melanin in melanosomes and by decreasing MITF-driven melanoma progression by increased GSK3β-mediated MITF degradation.

Plant Occurring Flavonoids as Modulators of the Aryl Hydrocarbon Receptor

The aryl hydrocarbon receptor (AhR) is a transcription factor deeply implicated in health and diseases. Historically identified as a sensor of xenobiotics and mainly toxic substances, AhR has recently become an emerging pharmacological target in cancer, immunology, inflammatory conditions, and aging. Multiple AhR ligands are recognized, with plant occurring flavonoids being the largest group of natural ligands of AhR in the human diet. The biological implications of the modulatory effects of flavonoids on AhR could be highlighted from a toxicological and environmental concern and for the possible pharmacological applicability. Overall, the possible AhR-mediated harmful and/or beneficial effects of flavonoids need to be further investigated, since in many cases they are contradictory. Similar to other AhR modulators, flavonoids commonly exhibit tissue, organ, and species-specific activities on AhR. Such cellular-context dependency could be probably beneficial in their pharmacotherapeutic use. Flavones, flavonols, flavanones, and isoflavones are the main subclasses of flavonoids reported as AhR modulators. Some of the structural features of these groups of flavonoids that could be influencing their AhR effects are herein summarized. However, limited generalizations, as well as few outright structure-activity relationships can be suggested on the AhR agonism and/or antagonism caused by flavonoids.

The Anticancer Effects of Flavonoids through miRNAs Modulations in Triple-Negative Breast Cancer

Triple- negative breast cancer (TNBC) incidence rate has regularly risen over the last decades and is expected to increase in the future. Finding novel treatment options with minimum or no toxicity is of great importance in treating or preventing TNBC. Flavonoids are new attractive molecules that might fulfill this promising therapeutic option. Flavonoids have shown many biological activities, including antioxidant, anti-inflammatory, and anticancer effects. In addition to their anticancer effects by arresting the cell cycle, inducing apoptosis, and suppressing cancer cell proliferation, flavonoids can modulate non-coding microRNAs (miRNAs) function. Several preclinical and epidemiological studies indicate the possible therapeutic potential of these compounds. Flavonoids display a unique ability to change miRNAs' levels via different mechanisms, either by suppressing oncogenic miRNAs or activating oncosuppressor miRNAs or affecting transcriptional, epigenetic miRNA processing in TNBC. Flavonoids are not only involved in the regulation of miRNA-mediated cancer initiation, growth, proliferation, differentiation, invasion, metastasis, and epithelial-to-mesenchymal transition (EMT), but also control miRNAs-mediated biological processes that significantly impact TNBC, such as cell cycle, immune system, mitochondrial dysregulation, modulating signaling pathways, inflammation, and angiogenesis. In this review, we highlighted the role of miRNAs in TNBC cancer progression and the effect of flavonoids on miRNA regulation, emphasizing their anticipated role in the prevention and treatment of TNBC.

A new flavonoid derivative exerts antitumor effects against androgen-sensitive to cabazitaxel-resistant prostate cancer cells

BACKGROUND

Our previous report has shown that the flavonoid 2'-hydroxyflavanone (2'-HF) showed inhibition of androgen receptor (AR) activity against androgen-sensitive prostate cancer (PCa) cells, LNCaP, and exhibited antitumor effects against androgen-insensitive PCa cells, PC-3, and DU145. In the present study, we prepared a derivative of 2'-HF, 16MS7F1924, and confirmed the effects of this derivative on PCa cells.

METHODS

The antiproliferation effects of 16MS7F1924 were investigated in PCa cells using LNCaP, PC-3, DU145 and docetaxel-resistant and cabazitaxel-resistant cell lines of PC-3-TxR/CxR and DU145-TxR/CxR. Prostate-specific antigen (PSA) and AR expression level in whole cells and the nucleus were confirmed in LNCaP by reverse transcriptase polymerase chain reaction and Western blot analysis. AR activity in LNCaP cells was confirmed by luciferase assay using PSA promoter-driven reporter. To analyze the antiproliferative effects, cell-based assays using flow cytometry, immunocytochemistry, and TUNEL assay as well as Western blot analysis were employed. Furthermore, PC-3, DU145 and each chemoresistant strain of human PCa cells were subcutaneously xenografted. The antitumor effects of 16MS7F1924 were evaluated in vivo.

RESULTS

16MS7F1924 showed antitumor effect on all PCa cells in a dose-dependent manner. 16MS7F1924 reduced the expression of PSA messenger RNA (mRNA) and protein and inhibited AR activity in a dose-dependent manner, while expression of AR protein and mRNA was reduced by 16MS7F1924. 16MS7F1924 induced mitotic catastrophe and apoptosis. Apoptotic cells were increased in a dose-dependent manner, and the apoptosis was mediated through the Akt pathway. Tumor growth was safely and significantly inhibited by both intraperitoneal and oral administration of 16MS7F1924 in vivo.

CONCLUSION

16MS7F1924 had sufficient antitumor activity against androgen-sensitive and cabazitaxel-resistant PCa cells and may be useful as a novel therapeutic agent overcoming hormone- and chemoresistant PCas.