A review on the chemotherapeutic potential of fisetin: In vitro evidences

Fisetin is a selective adenosine triphosphate-competitive inhibitor for mitogen-activated protein kinase kinase 4 to inhibit lipopolysaccharide-stimulated inflammation

The mitogen-activated protein kinase kinase 4 (MKK4), a member of the MAP kinase kinase family, directly phosphorylates and activates the c-Jun NH2-terminal kinases (JNK), in response to proinflammatory cytokines and cellular stresses. Regulation of the MKK4 activity is considered to be a novel approach for the prevention and treatment of inflammation. The aim of this study was to identify whether fisetin, a potential anti-inflammatory compound, targets MKK4-JNK cascade to inhibit lipopolysaccharide (LPS)-stimulated inflammatory response. RAW264 macrophage pretreated with fisetin following LPS stimulation was used as a cell model to investigate the transactivation and expression of related-inflammatory genes by transient transfection assay, electrophoretic mobility shift assay (EMSA), or enzyme-linked immunosorbent assay (ELISA), and cellular signaling as well as binding of related-signal proteins by Western blot, pull-down assay and kinase assay, and molecular modeling. The transactivation and expression of cyclooxygenase-2 (COX-2) gene as well as prostaglandin E2 (PGE2) secretion induced by LPS were inhibited by fisetin in a dose-dependent manner. Signaling transduction analysis demonstrated that fisetin selectively inhibited MKK4-JNK1/2 signaling to suppress the phosphorylation of transcription factor AP-1 without affecting the NF-κB and Jak2-Stat3 signaling as well as the phosphorylation of Src, Syk, and TAK1. Furthermore, in vitro and ex vivo pull-down assay using cell lysate or purified protein demonstrated that fisetin could bind directly to MKK4. Molecular modeling using the Molecular Operating Environment™ software indicated that fisetin docked into the ATP-binding pocket of MKK4 with a binding energy of -71.75 kcal/mol and formed a 1.70 Å hydrogen bound with Asp247 residue of MKK4. The IC50 of fisetin against MKK4 was estimated as 2.899 μM in the kinase assay, and the ATP-competitive effect was confirmed by ATP titration. Taken together, our data revealed that fisetin is a potent selective ATP-competitive MKK4 inhibitor to suppress MKK4-JNK1/2-AP-1 cascade for inhibiting LPS-induced inflammation.

Natural flavonoids as promising lactate dehydrogenase A inhibitors: Comprehensive in vitro and in silico analysis

The inhibitory potential of 17 flavonoids on lactate dehydrogenase A (LDHA), a key enzyme in the downstream process of aerobic glycolysis in cancer cells, is investigated. Fisetin exhibited excellent inhibitory activity (IC50 = 0.066 µM). Quercetin 3-β-D-glucoside, quercetin 3-galactoside, luteolin, neoeriocitrin, and luteolin 7-O-β-D-glucoside showed good inhibitory activity (IC50 = 1.397-15.730 µM). Biochanin A, baicalein, quercetin, scutellarein-7-glucuronide, diosmetin, baicalein 7-O-β-D-glucuronide, and apigenin 7-apioglucoside demonstrated moderate inhibitory activity (IC50 = 33.007-86.643 µM). Eriodictyol, quercetin 7-O-β-D-glucoside, apigenin 7-O-β-D-glucoside, and epicatechin were inactive. The Lineweaver-Burk plot showed that fisetin competitively inhibits NADH binding (Ki = 0.024 µM). Ki values for other compounds were calculated using the Cheng-Prusoff equation (Ki = 0.2799-2.1661 µM). The study revealed that the inhibitory effect of flavonoids varies with the number and position of OH groups and bound sugars. Molecular docking analyses indicated that flavonoids exhibited strong interactions with the NADH binding site of LDHA through hydrophobic interactions and hydrogen bonds. Molecular dynamic simulations tested the stability of the fisetin-LDHA complex over 100 ns and showed fisetin's high binding affinity to LDHA, maintaining strong hydrogen bonds. The binding energy of fisetin with LDHA was -33.928 kcal/mol, indicating its effectiveness as an LDHA inhibitor. Consequently, flavonoids identified as strong inhibitors could be potential cancer treatment sources through LDHA inhibition.

Natural bioactive compounds-The promising candidates for the treatment of intestinal failure-associated liver disease

Parenteral nutrition (PN) is a life-saving procedure conducted to maintain a proper nutritional state in patients with severe intestinal failure who cannot be fed orally. A serious complication of PN therapy is liver failure, known as intestinal failure-associated liver disease (IFALD). The pathogenesis of IFALD is multifactorial and includes inhibition of the farnesoid X receptor (FXR) by PN components, bacteria translocation from impaired intestines, and intravenous line-associated bloodstream infection. Currently, the most frequently researched therapeutic option for IFALD is using lipid emulsions based on soy or fish oil and, therefore, free from phytosterols known as FXR antagonists. Nevertheless, the potential side effects of the lack of soybean oil delivery seem to outweigh the benefits, especially in the pediatric population. PN admixture provides all the necessary nutrients; however, it is deprived of exogenous natural bioactive compounds (NBCs) of plant origin, such as polyphenols, characterized by health-promoting properties. Among them, many substances have already been known to demonstrate the hepatoprotective effect in various liver diseases. Therefore, searching for new therapeutic options for IFALD among NBCs seems reasonable and potentially successful. This review summarizes the recent research on polyphenols and their use in treating various liver diseases, especially metabolic dysfunction-associated steatotic liver diseases (MASLD). Furthermore, based on scientific reports, we have described the molecular mechanism of action of selected NBCs that exert hepatoprotective properties. We also summarized the current knowledge on IFALD pathogenesis, described therapeutic options undergoing clinical trials, and presented the future perspective of the potential use of NBCs in PN therapy.

Mini-encyclopedia of mitochondria-relevant nutraceuticals protecting health in primary and secondary care-clinically relevant 3PM innovation

Despite their subordination in humans, to a great extent, mitochondria maintain their independent status but tightly cooperate with the "host" on protecting the joint life quality and minimizing health risks. Under oxidative stress conditions, healthy mitochondria promptly increase mitophagy level to remove damaged "fellows" rejuvenating the mitochondrial population and sending fragments of mtDNA as SOS signals to all systems in the human body. As long as metabolic pathways are under systemic control and well-concerted together, adaptive mechanisms become triggered increasing systemic protection, activating antioxidant defense and repair machinery. Contextually, all attributes of mitochondrial patho-/physiology are instrumental for predictive medical approach and cost-effective treatments tailored to individualized patient profiles in primary (to protect vulnerable individuals again the health-to-disease transition) and secondary (to protect affected individuals again disease progression) care. Nutraceuticals are naturally occurring bioactive compounds demonstrating health-promoting, illness-preventing, and other health-related benefits. Keeping in mind health-promoting properties of nutraceuticals along with their great therapeutic potential and safety profile, there is a permanently growing demand on the application of mitochondria-relevant nutraceuticals. Application of nutraceuticals is beneficial only if meeting needs at individual level. Therefore, health risk assessment and creation of individualized patient profiles are of pivotal importance followed by adapted nutraceutical sets meeting individual needs. Based on the scientific evidence available for mitochondria-relevant nutraceuticals, this article presents examples of frequent medical conditions, which require protective measures targeted on mitochondria as a holistic approach following advanced concepts of predictive, preventive, and personalized medicine (PPPM/3PM) in primary and secondary care.

The characterization of traditional Chinese medicine natures and flavors using network pharmacology integrated strategy

Background and aim

Due to the complexity of TCM ingredients and medication compatibility, TCM cannot be used like chemical medicines. The theory of "Four Natures and five Flavors" provides a theoretical basis for the use of TCM. "Four Natures and five Flavors" are originated from pharmacological rules based on clinical practices. Whereas, How to describe and characterize "Natures"(Warm, Hot, Cold and Cool) and "Flavors" (Pungent, Sour, Sweet, Bitter and Salty) scientifically remain the issue that needs to be solved. The aim of this study is to establish the TCM characterization models based on the integrated pharmacology network strategy and provide a deeper understanding of TCM theory.

Experimental procedure

Five "Pungent-Neutral", nine "Sweet-Neutral and nine "Bitter-Neutral" TCMs were selected to characterize the "Flavors" (Pungent, Sweet and Bitter). Nine "Pungent-Warm" and nine "Bitter-Cold" TCMs were selected to characterize the "Natures" (Warm and Cold). The screened chemical ingredients were analyzed by classification and the screened characteristics targets were analyzed by GO and KEGG enrichment analysis.

Results and conclusion

In the "Pungent" group, flavonoids are the most. "Pungent" may have immune-regulatory effects and potential anticancer activity. In the "Sweet" group, isoflavones are the most. "Sweet" are related to effectively invigorate health. Fatty acids in the "Warm" group are the most. Flavonoids in the "Cold' group are far more than other components. "Warm" and "Cold" are both related to fatty acid and energy metabolism.

The development of nanocarriers for natural products

Natural bioactive compounds from plants exhibit substantial pharmacological potency and therapeutic value. However, the development of most plant bioactive compounds is hindered by low solubility and instability. Conventional pharmaceutical forms, such as tablets and capsules, only partially overcome these limitations, restricting their efficacy. With the recent development of nanotechnology, nanocarriers can enhance the bioavailability, stability, and precise intracellular transport of plant bioactive compounds. Researchers are increasingly integrating nanocarrier-based drug delivery systems (NDDS) into the development of natural plant compounds with significant success. Moreover, natural products benefit from nanotechnological enhancement and contribute to the innovation and optimization of nanocarriers via self-assembly, grafting modifications, and biomimetic designs. This review aims to elucidate the collaborative and reciprocal advancement achieved by integrating nanocarriers with botanical products, such as bioactive compounds, polysaccharides, proteins, and extracellular vesicles. This review underscores the salient challenges in nanomedicine, encompassing long-term safety evaluations of nanomedicine formulations, precise targeting mechanisms, biodistribution complexities, and hurdles in clinical translation. Further, this study provides new perspectives to leverage nanotechnology in promoting the development and optimization of natural plant products for nanomedical applications and guiding the progression of NDDS toward enhanced efficiency, precision, and safety. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Nanotechnology Approaches to Biology > Nanoscale Systems in Biology.

Folate conjugated albumin as a targeted nanocarrier for the delivery of fisetin: in silico and in vitro biological studies

Fisetin (FST), a natural flavonoid compound derived from various fruits and vegetables, including apple, strawberry, and onion, demonstrates potential for a wide range of pharmaceutical applications, including potential anticancer properties. However, challenges such as low bioavailability, poor aqueous solubility, and limited permeability restrict the use of FST in the pharmaceutical sector. Nowadays, targeted nanomedicines have garnered attention to overcome limitations associated with phytochemicals, including FST. In the present study, we have designed and successfully prepared folate-targeted FST nanoparticles (FFNPs). Characterization through DLS and FE-SEM revealed the successful preparation of monodisperse (PDI: 0.117), nanoscale-sized (150 nm), and spherical nanoparticles. Physicochemical characterization including FTIR, XRD, DSC, and TGA analysis, confirmed the encapsulation of the FST within the Folic acid (FA) - conjugated nanoparticles (CNPs) and revealed its amorphous nature. Molecular docking analysis revealed the strong binding affinity and specific amino acid interactions involved in the BSA-FST-FA complex, suggesting the potential synergistic effect of FST and FA in enhancing the therapeutic activity of the FFANPs. Cytotoxic assessments by the MTT assay, migration assay, AO-EtBr staining assay, colony formation assay, and cellular uptake study demonstrated enhanced anticancer efficacy, apoptosis induction, and enhanced uptake of FFNPs compared to pure FST. These findings propose prepared FFNPs as a promising targeted drug delivery nanocarrier for effective FST delivery in cancer therapy.

Therapeutic Potential Evaluation of Silk Sericin Stabilized Fisetin to Ulcerative Colitis

Ulcerative colitis is a chronic inflammatory bowel disease with a high recurrence rate. Natural phytochemical compounds are increasingly being considered as preventative and supportive treatments for this condition. However, the poor water solubility and stability of many of these compounds limit their effectiveness in vivo. To address this issue, fisetin (FT), a natural phytochemical with poor solubility, is stabilized using silk sericin (SS) to create a composite (SS/FT). The therapeutic potential of the SS/FT on ulcerative colitis is extensively investigated, and the results showed that it effectively alleviated the body weight loss and colon length shortening induced by dextran sulfate sodium. Notably, SS/FT downregulated the immune response, decreased colonic histopathological lesions, and reduced the cGAS/STING signal activation. This suggests that SS/FT may offer a promising therapy for treating ulcerative colitis.

Novel PEGylated cholephytosomes for targeting fisetin to breast cancer: in vitro appraisal and in vivo antitumoral studies

Fisetin (FIS) is a multifunctional bioactive flavanol that has been recently exploited as anticancer drug against various cancers including breast cancer. However, its poor aqueous solubility has constrained its clinical application. In the current work, fisetin is complexed for the first time with soy phosphatidylcholine in the presence of cholesterol to form a novel biocompatible phytosomal system entitled "cholephytosomes." To improve fisetin antitumor activity against breast cancer, stearylamine bearing cationic cholephytosomes (mPHY) were prepared and furtherly modified with hyaluronic acid (HPHY) to allow their orientation to cancer cells through their surface exposed phosphatidylserine and CD-44 receptors, respectively. In vitro characterization studies revealed promising physicochemical properties of both modified vesicles (mPHY and HPHY) including excellent FIS complexation efficiency (˷100%), improved octanol/water solubility along with a sustained drug release over 24 h. In vitro cell line studies against MDA-MB-231 cell line showed about 10- and 3.5-fold inhibition in IC50 of modified vesicles compared with free drug and conventional drug-phospholipid complex, respectively. Preclinical studies revealed that both modified cholephytosomes (mPHY and HPHY) had comparable cytotoxicity that is significantly surpassing free drug cytotoxicity. TGF-β1and its non-canonical related signaling pathway; ERK1/2, NF-κB, and MMP-9 were involved in halting tumorigenesis. Thus, tailoring novel phytosomal nanosystems for FIS could open opportunity for its clinical utility against cancer.

Molecular mechanisms involved in the destabilization of two types of R3-R4 tau fibrils associated with chronic traumatic encephalopathy by Fisetin

Chronic traumatic encephalopathy is a neurodegenerative tauopathy pathologically characterized by fibrillary tau aggregates in the depth of sulci. Clearing fibrous tau aggregates is considered a promising strategy in the treatment of CTE. Fisetin (FS), a natural polyphenolic small molecule, was confirmed to disassociate the tau filaments in vitro. However, the molecular mechanisms of FS in destabilizing the CTE-related R3-R4 tau fibrils remain largely unknown. In this study, we compared the atomic-level structural differences of the two types of CTE-related R3-R4 tau fibrils and explored the influence and molecular mechanisms of FS on the two types of fibrils by conducting multiple molecular dynamics (MD) simulations. The results reveal that the type 1 fibril displays higher structural stability than the type 2 fibril, with a lower root-mean-square-fluctuation value and higher β-sheet structure probability. FS can destabilize both types of fibrils by decreasing the β-sheet structure content, interrupting the mainchain H-bond network, and increasing the solvent accessible surface area and β7-β8 angle of the fibrils. H-bonding, π-π stacking and cation-π are the common interactions driving FS molecules binding on the two types of fibrils, while the hydrophobic interaction occurs only in the type 2 fibril. Due to the relatively short simulation time, our study captures the early molecular mechanisms. However, it does provide beneficial information for the design of drugs to prevent or treat CTE.

Inhibition mechanism of fisetin on acetylcholinesterase and its synergistic effect with galantamine

The search for acetylcholinesterase (AChE) inhibitors produced by natural sources is of great significance for the prevention and therapy of Alzheimer's disease and has been widely concerned. In this study, fisetin, a flavonoid compound of plant origin, displayed a mixed inhibition mode on AChE (IC50 = 8.88 ± 0.14 μM). Fluorescence spectra analysis revealed that fisetin statically quenched AChE fluorescence, and the ground state complex was formed by hydrogen bonds and hydrophobic interactions. Circular dichroism assays showed that fisetin induced AChE structure loosened with a decrease in α-helix structure (from 20.6 % to 19.5 %). Computer simulation exhibited that fisetin bound to both the peripheral anionic site (PAS) and the catalytic active site (CAS) and increased the stability of the AChE. Interestingly, the combination of fisetin and galantamine enhanced the binding affinity between AChE and galantamine and induced AChE structure further loosened, while the inhibition mode was still the mixed type. The heatmap analysis indicated that galantamine (0.2 μM) combined with fisetin (2.25 μM) had a significant synergy on AChE inhibition, probably because fisetin binding at the PAS-AChE induced conformation changes of the gorge and CAS, which enhanced galantamine binding affinity with CAS, and a further loose structure of AChE was induced by the mixture, so finally the interaction between the substrate and AChE was strongly affected. This work may offer a theoretical reference for the functional research of fisetin as a potential AChE inhibitor and an enhanced supplement for galantamine.

Fisetin, a dietary flavonoid, promotes transintestinal cholesterol excretion through the activation of PPARδ

Fisetin, a dietary polyphenol abundantly found in strawberries, exhibits a broad spectrum of health-promoting activities, including antihyperlipidemic effects. This study aimed to investigate the regulatory effect of fisetin on cholesterol elimination through novel transintestinal cholesterol excretion (TICE) pathway. A hypercholesterolemic mouse model and human colon epithelial cancer cell line Caco-2 were utilized to conduct the study. In hypercholesterolemic mice, fisetin (25 mg/kg) treatment reduced serum total cholesterol by 46.48% and significantly decreased lipid accumulation in the liver. Furthermore, fisetin administration led to a substantial increase in the fecal neutral sterol contents, including coprostanol, coprostanone, dihydrocholesterol, and cholesterol. Specifically, these sterol contents increased by approximately 224.20%, 151.40%, 70.40% and 50.72% respectively. The fluorescence intensity of 22-NBD-cholesterol in intestinal perfusion increased by 95.94% in fisetin group (25 mg/kg), indicating that fisetin stimulated TICE. In high cholesterol-induced Caco-2 cells, fisetin at a concentration of 30 μM reduced total cholesterol and free cholesterol by 37.21% and 45.30% respectively, stimulated cholesterol excretion, and inhibited cholesterol accumulation. Additionally, fisetin upregulated the gene and protein expression of cholesterol efflux transporters ABCG5/G8 and ABCB1, while downregulating the cholesterol uptake regulator NPC1L1. Furthermore, fisetin increased LDLR protein expression and decreased PCSK9 expression. Notably, fisetin significantly activated nuclear receptor PPARδ in Caco-2 cells. PPARδ antagonist pretreatment counteracted the regulatory effects of fisetin on TICE regulators, suggesting fisetin lowered cholesterol through enhancing TICE by activation of intestinal PPARδ. Fisetin could be used as functional dietarysupplement for eliminating cholesterol and reducing the incidence of cardiovascular diseases.

Sensitizing chemotherapy for glioma with fisetin mediated by a microenvironment-responsive nano-drug delivery system

Drug resistance has become an obstacle to successful cancer chemotherapies, with therapeutic agents effectively traversing the blood-brain barrier (BBB) remaining a great challenge. A microenvironment responsive and active targeting nanoparticle was constructed to enhance the penetration of drugs, leading to improved therapeutic effects. Dynamic light scattering demonstrated that the prepared nanoparticle had a uniform size. The cRGD modification renders the nanoparticle with active targeting capabilities to traverse the BBB for chemotherapy. The disulfide-bond-containing nanoparticle can be disintegrated in response to a high concentration of endogenous glutathione (GSH) within the tumor microenvironment (TME) for tumor-specific drug release, resulting in more effective accumulation. Notably, the released fisetin further increased the uptake of doxorubicin by glioma cells and exerted synergistic effects to promote apoptosis, induce cellular G2/M cycle arrest, and inhibit cell proliferation and migration in vitro. Moreover, the nanoparticle showed favorable anti-glioma effects in vivo. Our study provides a new strategy to overcome drug resistance by utilizing a natural product to sensitize conventional chemotherapeutics with well-designed targeted nanodelivery systems for cancer treatment.

Natural compounds: Wnt pathway inhibitors with therapeutic potential in lung cancer

The Wnt/β-catenin pathway is abnormally activated in most lung cancer tissues and considered to be an accelerator of carcinogenesis and lung cancer progression, which is closely related to increased morbidity rates, malignant progression, and treatment resistance. Although targeting the canonical Wnt/β-catenin pathway shows significant potential for lung cancer therapy, it still faces challenges owing to its complexity, tumor heterogeneity and wide physiological activity. Therefore, it is necessary to elucidate the role of the abnormal activation of the Wnt/β-catenin pathway in lung cancer progression. Moreover, Wnt inhibitors used in lung cancer clinical trials are expected to break existing therapeutic patterns, although their adverse effects limit the treatment window. This is the first study to summarize the research progress on various compounds, including natural products and derivatives, that target the canonical Wnt pathway in lung cancer to develop safer and more targeted drugs or alternatives. Various natural products have been found to inhibit Wnt/β-catenin in various ways, such as through upstream and downstream intervention pathways, and have shown encouraging preclinical anti-tumor efficacy. Their diversity and low toxicity make them a popular research topic, laying the foundation for further combination therapies and drug development.

Fisetin's Promising Antitumor Effects: Uncovering Mechanisms and Targeting for Future Therapies

Background  Cancer remains a critical global health challenge and a leading cause of mortality. Flavonoids found in fruits and vegetables have gained attention for their potential anti-cancer properties. Fisetin, abundantly present in strawberries, apples, onions, and other plant sources, has emerged as a promising candidate for cancer prevention. Epidemiological studies linking a diet rich in these foods to lower cancer risk have sparked extensive research on fisetin's efficacy. Objective  This review aims to comprehensively explore the molecular mechanisms of fisetin's anticancer properties and investigate its potential synergistic effects with other anticancer drugs. Furthermore, the review examines the therapeutic and preventive effects of fisetin against various cancers. Methods  A systematic analysis of the available scientific literature was conducted, including research articles, clinical trials, and review papers related to fisetin's anticancer properties. Reputable databases were searched, and selected studies were critically evaluated to extract essential information on fisetin's mechanisms of action and its interactions with other anticancer drugs. Results  Preclinical trials have demonstrated that fisetin inhibits cancer cell growth through mechanisms such as cell cycle alteration, induction of apoptosis, and activation of the autophagy signaling pathway. Additionally, fisetin reduces reactive oxygen species levels, contributing to its overall anticancer potential. Investigation of its synergistic effects with other anticancer drugs suggests potential for combination therapies. Conclusion  Fisetin, a bioactive flavonoid abundant in fruits and vegetables, exhibits promising anticancer properties through multiple mechanisms of action. Preclinical trials provide a foundation for further exploration in human clinical trials. Understanding fisetin's molecular mechanisms is vital for developing novel, safe, and effective cancer prevention and treatment strategies. The potential synergy with other anticancer drugs opens new avenues for combination therapies, enhancing cancer management approaches and global health outcomes.

Fisetin induces apoptosis in human skin cancer cells through downregulating MTH1

Fisetin, a natural flavonoid molecule, has been shown to have anticancer properties against various malignancies. In this investigation, we discovered that Fisetin decreased cell viability of both the treated skin cancer cell lines A375 and A431 in a dose and time-dependent manner. The IC50 values ranging from 57.60 µM ± 6.59 to 41.70 µM ± 1.25 in A375 and 48.70 µM ± 5.49 to 33.67 µM ± 1.03 for A431 at the observed time ranging between 24 h to 72 h of treatment remained quite enthusiastic when compared with the normal HEK 293 cells. Fisetin significantly decreased colony formation and migratory ability of the cancer cells. Flow cytometry analysis revealed that Fisetin significantly restricted the progression of skin cancer cells in the G0/G1 phase of the cell cycle and induced cells to undergo apoptosis by increasing reactive oxygen species, decreasing mitochondrial membrane potential, and elevating the count of early and late apoptotic cells. Our in silico studies of molecular docking followed by molecular dynamics simulation found that the interactions and stability of MTH1 protein with Fisetin further showed a considerable binding affinity for MTH1 (-11.4 kcal/mol) and developed stable complexes maintained throughout 100 ns trajectories. Our western blot analysis endorsed this. We found that Fisetin downregulated the expression levels of MTH1 also in addition, it played a crucial role in regulation of apoptotic events in cancer cells. We therefore, conclude that Fisetin anticancer properties against skin cancer cells are mediated through MTH1 inhibition followed by ATM and P53 upregulation.Communicated by Ramaswamy H. Sarma.

Targeting Cell Signaling Pathways in Lung Cancer by Bioactive Phytocompounds

Lung cancer is a heterogeneous group of malignancies with high incidence worldwide. It is the most frequently occurring cancer in men and the second most common in women. Due to its frequent diagnosis and variable response to treatment, lung cancer was reported as the top cause of cancer-related deaths worldwide in 2020. Many aberrant signaling cascades are implicated in the pathogenesis of lung cancer, including those involved in apoptosis (B cell lymphoma protein, Bcl-2-associated X protein, first apoptosis signal ligand), growth inhibition (tumor suppressor protein or gene and serine/threonine kinase 11), and growth promotion (epidermal growth factor receptor/proto-oncogenes/phosphatidylinositol-3 kinase). Accordingly, these pathways and their signaling molecules have become promising targets for chemopreventive and chemotherapeutic agents. Recent research provides compelling evidence for the use of plant-based compounds, known collectively as phytochemicals, as anticancer agents. This review discusses major contributing signaling pathways involved in the pathophysiology of lung cancer, as well as currently available treatments and prospective drug candidates. The anticancer potential of naturally occurring bioactive compounds in the context of lung cancer is also discussed, with critical analysis of their mechanistic actions presented by preclinical and clinical studies.

Effect and mechanism of Fisetin on myocardial damage induced by Patulin

OBJECTIVES OF THE STUDY

The aim of this study is to investigate whether fisetin can effectively reduce the myocardial damage induced by patulin. This study also aims to reveal the mechanism and target of fisetin in inhibiting myocardial damage.

MATERIALS AND METHODS

Network pharmacology was used to screen the targets of fisetin on myocardial damage and the regulatory network of active ingredients-drug targets was constructed. GO and KEGG enrichment analyses were performed to screen out the key pathways and targets of fisetin on myocardial damage. Patulin induced apoptosis in H9c2 cardiomyocytes to verify the key targets. The mechanism of fisetin in inhibiting myocardial damage was determined.

RESULTS

FIS can reduce the apoptosis of cardiomyocytes by protecting cardiomyocytes from PAT injury. According to the results of network pharmacology analysis, combined with enzyme activity detection and WB experiment, it was found that the mechanism of FIS to reduce myocardial damage may be related to the P53 signaling pathway, Caspase3/8/9 and Bax/Bcl-2.

CONCLUSION

FIS plays a protective role in PAT-induced myocardial damage. On the one hand, FIS inhibits the protein overexpression of P53, Caspase-9 and Bax. On the other hand, FIS enhances the protein expression of Bcl-2.

Self-assembled fisetin-phospholipid complex: Fisetin-integrated phytosomes for effective delivery to breast cancer

Nowadays, fisetin (FIS) is extensively studied as potent anticancer surrogate with a multitarget actions against various types of cancers including breast cancer. However, its poor aqueous solubility handicapped its clinical utility. The current work endeavored, for the first time, to develop FIS phytosomes (FIS-PHY) for improving its physicochemical properties and subsequently its anticancer activity. Optimization of FIS- phytosomes involved different preparation techniques (Thin film hydration and ethanol injection) and different FIS: phospholipid molar ratios (1:1, 1:2, and 1:3). Complex formation was confirmed by complexation efficiency, infrared spectroscopy (IR), solubility studies and transmission electron microscope. The optimized FIS-PHY of 1:1 M ratio (PHY1) exhibited a nanometric particle size of 233.01 ± 9.46 nm with homogenous distribution (PDI = 0.27), negative zeta potential of - 29.41 mV, 100% complexation efficiency and controlled drug release over 24 h. In-vitro cytotoxicity study showed 2.5-fold decrease in IC50 of PHY1 compared with free FIS. Also, pharmacodynamic studies confirmed the promoted cytotoxicity of PHY1 against breast cancer through modulating TGF-β1/MMP-9 molecular pathways of tumorigenesis. Overall, overcoming FIS drawbacks were successfully achieved through development of innovative biocompatible phytosomal system.

Fisetin Delays Postovulatory Oocyte Aging by Regulating Oxidative Stress and Mitochondrial Function through Sirt1 Pathway

The quality of oocytes determines the development potential of an embryo and is dependent on their timely fertilization after ovulation. Postovulatory oocyte aging is an inevitable factor during some assisted reproduction technology procedures, which results in poor fertilization rates and impairs embryo development. We found that fisetin, a bioactive flavonol contained in fruits and vegetables, delayed postovulatory oocyte aging in mice. Fisetin improved the development of aged oocytes after fertilization and inhibited the Sirt1 reduction in aged oocytes. Fisetin increased the GSH level and Sod2 transcription level to inhibit ROS accumulation in aged oocytes. Meanwhile, fisetin attenuated aging-induced spindle abnormalities, mitochondrial dysfunction, and apoptosis. At the molecular level, fisetin decreased aging-induced aberrant expression of H3K9me3. In addition, fisetin increased the expression levels of the mitochondrial transcription factor Tfam and the mitochondrial genes Co2 and Atp8 by upregulating Sirt1 in aged oocytes. Finally, inhibition of Sirt1 reversed the anti-aging effects of fisetin. Taken together, fisetin delayed postovulatory oocyte aging by upregulating Sirt1.

Antiproliferative Mechanisms of a Polyphenolic Combination of Kaempferol and Fisetin in Triple-Negative Breast Cancer Cells

Herein, we investigate the combinatorial therapeutic effects of naturally occurring flavonoids kaempferol (K) and fisetin (F) on triple-negative breast cancer (TNBC: MDA-MB-231 cell line). Dose-dependent MTT assay results show that K and F exhibited cytotoxicity in MDA-MB-231 cells at 62 and 75 μM (IC50), respectively, after 24 h. However, combined K + F led to 40% and more than 50% TNBC cell death observed at 10 and 20 μM, respectively, which revealed the synergistic association of both. The combination of K and F was determined to be more effective in inhibiting cell viability than either of the agents alone. The morphological changes associated with significant apoptotic cell death were observed under a fluorescent microscope, strongly supporting the synergistic association between K and F. We also proposed that combining the effects of both polyphenols, as opposed to their individual effects, would increase their in vitro efficacy. Furthermore, we assessed the cell death pathway by the combinational treatment via reactive oxygen species-induced DNA damage and the mitochondrially mediated apoptotic pathway. This study reveals the prominent synergistic role of phytochemicals, which helps in elevating the therapeutic efficacy of dietary nutrients and that anticancer effects may be a result of nutrients that act in concert.

Targeting cellular senescence with senotherapeutics: senolytics and senomorphics

The concept of geroscience is that since ageing is the greatest risk factor for many diseases and conditions, targeting the ageing process itself will have the greatest impact on human health. Of the hallmarks of ageing, cellular senescence has emerged as a druggable therapeutic target for extending healthspan in model organisms. Cellular senescence is a cell state of irreversible proliferative arrest driven by different types of stress, including oncogene-induced stress. Many senescent cells (SnCs) develop a senescent-associated secretory phenotype (SASP) comprising pro-inflammatory cytokines, chemokines, proteases, bioactive lipids, inhibitory molecules, extracellular vesicles, metabolites, lipids and other factors, able to promote chronic inflammation and tissue dysfunction. SnCs up-regulate senescent cell anti-apoptotic pathways (SCAPs) that prevent them from dying despite the accumulation of damage to DNA and other organelles. These SCAPs and other pathways altered in SnCs represent therapeutic targets for the development of senotherapeutic drugs that induce selective cell death of SnCs, specifically termed senolytics or suppress markers of senescence, in particular the SASP, termed senomorphics. Here, we review the current state of the development of senolytics and senomorphics for the treatment of age-related diseases and disorders and extension of healthy longevity. In addition, the challenges of documenting senolytic and senomorphic activity in pre-clinical models and the current state of the clinical application of the different senotherapeutics will be discussed.

Fisetin Ameliorates Diabetic Nephropathy-Induced Podocyte Injury by Modulating Nrf2/HO-1/GPX4 Signaling Pathway

Diabetic nephropathy (DN) is one of the most severe microvascular complications of diabetes and has become the leading cause of end-stage renal disease formation. The pathogenesis of diabetic nephropathy is very complex and is still not fully understood. Fisetin is a flavonoid polyphenolic compound that is widely found in different fruits, vegetables, and medicinal plants. Many studies have indicated that it has a variety of pharmacological activities. In this study, we investigated the mechanism of action of fisetin in the protection of DN-induced podocyte injury both in vivo and in vitro. Results showed that fisetin could reduce high glucose (HG)-induced podocyte injury and streptozotocin (STZ)-induced diabetic nephropathy in mice. According to the histopathological staining results, fisetin ameliorated DN-induced glomerular injury in a dose-dependent manner. Western blot and immunofluorescence results showed that fisetin effectively promoted the expression of podocyte functional integrity marker proteins and inhibited the expression of podocyte injury marker proteins. In addition, according to the Western blot and RT-qPCR results, fisetin activates the nuclear translocation of Nrf2 to exert antioxidative stress ability and affects the expression of downstream antioxidant enzymes HO-1, GPX4, and other ferroptosis-related markers, thereby protecting against HG-induced podocyte ferroptosis and oxidative stress injury in DN mice. In summary, this study demonstrated that fisetin could enhance the antioxidative stress capacity of DN mice by promoting the activation of the Nrf2/HO-1/GPX4 signaling pathway in renal tissues, and attenuated HG-induced podocytes injury and STZ-induced DN in mice.

New Trends in Aging Drug Discovery

Aging is considered the main risk factor for many chronic diseases that frequently appear at advanced ages. However, the inevitability of this process is being questioned by recent research that suggests that senescent cells have specific features that differentiate them from younger cells and that removal of these cells ameliorates senescent phenotype and associated diseases. This opens the door to the design of tailored therapeutic interventions aimed at reducing and delaying the impact of senescence in life, that is, extending healthspan and treating aging as another chronic disease. Although these ideas are still far from reaching the bedside, it is conceivable that they will revolutionize the way we understand aging in the next decades. In this review, we analyze the main and well-validated cellular pathways and targets related to senescence as well as their implication in aging-associated diseases. In addition, the most relevant small molecules with senotherapeutic potential, with a special emphasis on their mechanism of action, ongoing clinical trials, and potential limitations, are discussed. Finally, a brief overview of alternative strategies that go beyond the small molecule field, together with our perspectives for the future of the field, is provided.

Increase in Anticancer Drug-Induced Toxicity by Fisetin in Lung Adenocarcinoma A549 Spheroid Cells Mediated by the Reduction of Claudin-2 Expression

Claudin-2 (CLDN2), a component of tight junction, is involved in the reduction of anticancer drug-induced toxicity in spheroids of A549 cells derived from human lung adenocarcinoma. Fisetin, a dietary flavonoid, inhibits cancer cell growth, but its effect on chemosensitivity in spheroids is unknown. Here, we found that fisetin (20 μM) decreases the protein level of CLDN2 to 22.3%. Therefore, the expression mechanisms were investigated by real-time polymerase chain reaction and Western blotting. Spheroids were formed in round-bottom plates, and anticancer drug-induced toxicity was measured by ATP content. Fisetin decreased the phosphorylated-Akt level, and CLDN2 expression was decreased by a phosphatidylinositol 3-kinase (PI3K) inhibitor, suggesting the inhibition of PI3K/Akt signal is involved in the reduction of CLDN2 expression. Hypoxia level, one of the hallmarks of tumor microenvironment, was reduced by fisetin. Although fisetin did not change hypoxia inducible factor-1α level, it decreased the protein level of nuclear factor erythroid 2-related factor 2, a stress response factor, by 25.4% in the spheroids. The toxicity of doxorubicin (20 μM) was enhanced by fisetin from 62.8% to 40.9%, which was rescued by CLDN2 overexpression (51.7%). These results suggest that fisetin can enhance anticancer drug toxicity in A549 spheroids mediated by the reduction of CLDN2 expression.

Recent advances in potential of Fisetin in the management of myocardial ischemia-reperfusion injury-A systematic review

BACKGROUND

The primary therapeutic strategy in managing ischemic heart diseases is to restore the perfusion of the myocardial ischemic area by surgical methods that often result in an unavoidable injury called ischemia-reperfusion injury (IR). Fisetin is an effective flavonoid with antioxidant and anti-inflammatory properties, proven to be cardioprotective against IR injury in both in-vitro and invivo models, apart from its promising health benefits against cancer, diabetes, and neurodegenerative ailments.

PURPOSE

The potential of fisetin in attenuating myocardial IR is inconclusive as the effectiveness of fisetin needs more understanding in terms of its possible target sites and underlying different mechanisms. Considering the surge in recent scientific interests in fisetin as a pharmacological agent, this review not only updates the existing preclinical and clinical studies with fisetin and its underlying mechanisms but also summarizes its possible targets during IR protection.

METHODS

We performed a literature survey using search engines Pubmed, PMC, Science direct, Google, and research gate published across the years 2006-2021. The relevant studies were extracted from the databases with the combinations of the following keywords and summarized: myocardial ischemia-reperfusion injury, natural products, flavonoid, fisetin, PI3K, JAK-STAT, Nrf2, PKC, JNK, autophagy.

RESULTS

Fisetin is reported to be effective in attenuating IR injury by delaying the clotting time, preserving the mitochondrial function, reducing oxidative stress, and inhibiting GSK 3β. But it failed to protect diseased cardiomyocytes challenged to IR. As discussed in the current review, fisetin not only acts as a conventional antioxidant and anti-inflammatory agent to exert its biological effect but may also exert modulatory action on the cellular metabolism and adaptation via direct action on various signalling pathways that comprise PI3K, JAK-STAT, Nrf2, PKC, JNK, and autophagy. Moreover, the dosage of fisetin and co-morbidities like diabetes and obesity are found to be detrimental factors for cardioprotection.

CONCLUSION

For further evaluation and smooth clinical translation of the fisetin molecule in IR treatment, researchers should pay close attention to the potential of fisetin to possibly alter the key cardioprotective pathways and dosage, as the efficacy of fisetin is tissue and cell type-specific and varies with different doses.

Exploration of Potential Targets and Mechanisms of Fisetin in the Treatment of Non-Small-Cell Lung Carcinoma via Network Pharmacology and In Vitro Validation

Purpose

The morbidity and fatality rates of non-small-cell lung cancer (NSCLC) were high, although a combination of multiple treatments was used. Fisetin, a small flavonoid compound, had shown anticancer activities. Thus, we aimed at exploring the mechanisms of Fisetin in the treatment of NSCLC.

Methods

TCMSP and Swiss target tools were used to screen the targets of Fisetin, and GeneCards was used to collect the genes related to NSCLC. The genes common to Fisetin and NSCLC were obtained by Venn analysis, whose possible functions were further annotated. A “Compound-Target-Disease” network was then constructed and hub genes were filtered. Also, molecular docking was performed to predict the binding abilities between Fisetin and the hub genes. Then, the effects of Fisetin on the expression of hub genes in lung adenocarcinoma cells were preliminarily evaluated in vitro.

Results

A total of 131 genes common to Fisetin and NSCLC were filtered out, which might be enriched in several biological processes including antioxidation, cell proliferation, and various signaling pathways, such as PI3K-Akt and IL-17 signaling pathways. Among them, PIK3R1, CTNNB1, JUN, EGFR, and APP might be the hub genes. Molecular docking indicated the close bond between Fisetin and them. Experiments implied a possible effect of Fisetin on the expression of hub genes in A549 cells.

Conclusion

The present study found a series of novel targets and pathways for Fisetin treating NSCLC. Multiple angles, targets, and pathways were involved in the biological processes, which need to be verified in further experiments.

Exploring the role of senescence inducers and senotherapeutics as targets for anticancer natural products

During the last few decades, cancer has remained one of the deadliest diseases that endanger human health, emphasizing urgent drug discovery. Cellular senescence has gained a great deal of attention in recent years because of its link to the development of cancer therapy. Senescent cells are incapable of proliferating due to irreversibly inhibited the initiation of the cell cycle pathways. However, senescent cells aggregate in tissues and produce a pro-inflammatory secretome called senescence-associated secretory phenotype (SASP) that can cause serious harmful effects if not managed properly. There is mounting evidence that senescent cells lead to various phases of tumorigenesis in various anatomical sites, owing mostly to the paracrine activities of the SASP. Therefore, a new treatment field called senotherapeutics has been established. Senotherapeutics are newly developed anticancer agents that have been demonstrated to inhibit cancer effectively. In light of recent findings, several promising natural products have been identified as senescence inducers and senotherapeutics, including, miliusanes, epigallocatechin gallate, phloretin, silybin, resveratrol, genistein, sulforaphane, quercetin, allicin, fisetin, piperlongumine, berberine, triptolide, tocotrienols and curcumin analogs. Several of them have already been validated through preclinical trials and exert an enormous potential for clinical trials. This review article focuses on and summarises the latest advances on cellular senescence and its potential as a target for cancer treatment and highlights the well-known natural products as senotherapeutics for cancer treatment.

Complexation of phytochemicals with cyclodextrins and their derivatives- an update

Bioactive phytochemicals from natural source have gained tremendous interest over several decades due to their wide and diverse therapeutic activities playing key role as functional food supplements, pharmaceutical and nutraceutical products. Nevertheless, their application as therapeutically active moieties and formulation into novel drug delivery systems are hindered due to major drawbacks such as poor solubility, bioavailability and dissolution rate and instability contributing to reduction in bioactivity. These drawbacks can be effectively overcome by their complexation with different cyclodextrins. Present article discusses complexation of phytochemicals varying from flavonoids, phenolics, triterpenes, and tropolone with different natural and synthetic cyclodextrins. Moreover, the article summarizes complexation methods, complexation efficiency, stability, stability constants and enhancement in rate and extent of dissolution, bioavailability, solubility, in vivo and in vitro activities of reported complexed phytochemicals. Additionally, the article presents update of published patent details comprising of complexed phytochemicals of therapeutic significance. Thus, phytochemical cyclodextrin complexes have tremendous potential for transformation into drug delivery systems as substantiated by significant outcome of research findings.

Fisetin Attenuates Doxorubicin-Induced Cardiomyopathy In Vivo and In Vitro by Inhibiting Ferroptosis Through SIRT1/Nrf2 Signaling Pathway Activation

Doxorubicin (DOX) is an anthracycline antibiotic that is used extensively for the management of carcinoma; however, its clinical application is limited due to its serious cardiotoxic side effects. Ferroptosis represents iron-dependent and reactive oxygen species (ROS)-related cell death and has been proven to contribute to the progression of DOX-induced cardiomyopathy. Fisetin is a natural flavonoid that is abundantly present in fruits and vegetables. It has been reported to exert cardioprotective effects against DOX-induced cardiotoxicity in experimental rats. However, the underlying mechanisms remain unknown. The present study investigated the cardioprotective role of fisetin and the underlying molecular mechanism through experiments in the DOX-induced cardiomyopathy rat and H9c2 cell models. The results revealed that fisetin treatment could markedly abate DOX-induced cardiotoxicity by alleviating cardiac dysfunction, ameliorating myocardial fibrosis, mitigating cardiac hypertrophy in rats, and attenuating ferroptosis of cardiomyocytes by reversing the decline in the GPX4 level. Mechanistically, fisetin exerted its antioxidant effect by reducing the MDA and lipid ROS levels and increasing the glutathione (GSH) level. Moreover, fisetin exerted its protective effect by increasing the SIRT1 expression and the Nrf2 mRNA and protein levels and its nuclear translocation, which resulted in the activation of its downstream genes such as HO-1 and FTH1. Selective inhibition of SIRT1 attenuated the protective effects of fisetin in the H9c2 cells, which in turn decreased the GSH and GPX4 levels, as well as Nrf2, HO-1, and FTH1 expressions. In conclusion, fisetin exerts its therapeutic effects against DOX-induced cardiomyopathy by inhibiting ferroptosis via SIRT1/Nrf2 signaling pathway activation.

Fisetin alleviates thioacetamide-induced hepatic fibrosis in rats by inhibiting Wnt/β-catenin signaling pathway

BACKGROUND

Liver fibrosis is a chronic wound-healing response to liver injury of various origins and represents a major health problem.

OBJECTIVE

The current study endeavored to investigate the repressing effect of fisetin on hepatic fibrosis induced by thioacetamide (TAA) in rats.

MATERIALS AND METHODS

Rats were injected with TAA (200 mg/kg) intraperitoneally twice per week for 6 weeks to induce liver fibrosis. Fisetin (50 and 100 mg/kg/day) or silymarin (50 mg/kg/day) were given orally on a daily basis along with TAA. Liver function parameters, oxidative stress, inflammatory and fibrogenic biomarkers as well as wnt3a, β-catenin, glycogen synthase kinase 3 (GSK-3β) and cyclin D1 were estimated. Histoapthological and immunohistochemical examinations were performed.

RESULTS

Fisetin restored normal liver functions, increased reduced glutathione (GSH) level and decreased malondialdehyde (MDA), as well as inflammatory biomarkers including; tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6). Additionally, it lessened transforming growth factor β1 (TGF-β1), collagen I and tissue inhibitor of metalloproteinase-1 (TIMP-1) levels as well as elevated matrix metalloproteinase-9 (MMP-9) hepatic content. Furthermore, fisetin significantly suppressed wnt3a gene expression associated with decreased β-catenin and increased GSK-3β levels. Moreover, fisetin decreased the progress of histologic hepatic fibroplasia and diminished hepatic expression of α-SMA and cyclin D1.

CONCLUSION

Fisetin curbed liver fibrosis and exhibited superior activity over silymarin through inhibition of hepatic stellate cells (HSCs) activation and proliferation via suppressing the Wnt/β-catenin pathway, modulating MMP-9 and TIMP-1, and inhibiting multiple profibrogenic factors, besides its antioxidant and anti-inflammatory effects. Therefore, fisetin is a promising therapeutic candidate for hepatic fibrosis.

Regulation of micro-RNA, epigenetic factor by natural products for the treatment of cancers: Mechanistic insight and translational Association

From onset to progression, cancer is a ailment that might take years to grow. All common epithelial malignancies, have a long latency period, frequently 20 years or more, different gene may contain uncountable mutations if they are clinically detectable. MicroRNAs (miRNAs) are around 22nt non-coding RNAs that control gene expression sequence-specifically through translational inhibition or messenger degradation of RNA (mRNA). Epigenetic processes of miRNA control genetic variants through genomic DNA methylation, post-translation histone modification, rework of the chromatin, and microRNAs. The field of miRNAs has opened a new era in understanding small non-coding RNAs since discovering their fundamental mechanisms of action. MiRNAs have been found in viruses, plants, and animals through molecular cloning and bioinformatics approaches. Phytochemicals can invert the epigenetic aberrations, a leading cause of the cancers of various organs, and act as an inhibitor of these changes. The advantage of phytochemicals is that they only function on cells that cause cancer without affecting normal cells. Phytochemicals appear to play a significant character in modulating miRNA expression, which is linked to variations in oncogenes, tumor suppressors, and cancer-derived protein production, according to several studies. In addition to standard anti-oxidant or anti-inflammatory properties, the initial epigenetic changes associated with cancer prevention may be modulated by many polyphenols. In correlation with miRNA and epigenetic factors to treat cancer some of the phytochemicals, including polyphenols, curcumin, resveratrol, indole-3-carbinol are studied in this article.

Fisetin Deters Cell Proliferation, Induces Apoptosis, Alleviates Oxidative Stress and Inflammation in Human Cancer Cells, HeLa

Background: Fisetin, a flavonol profusely found in vegetables and fruits, exhibited a myriad of properties in preclinical studies to impede cancer growth. Purpose: This study was proposed to delineate molecular mechanisms through analysing the modulated expression of various molecular targets in HeLa cells involved in proliferation, apoptosis and inflammation. Methods: MTT assay, flow cytometry, nuclear morphology, DNA fragmentation and Annexin–Pi were performed to evaluate the anti-cancer potential of fisetin. Furthermore, qPCR and proteome profiler were performed to analyse the expression of variety of gene related to cell death, cell proliferation, oxidative stress and inflammation and cancer pathways. Results: Fisetin demonstrated apoptotic inducing ability in HeLa cells, which was quite evident through nuclear morphology, DNA ladder pattern, decreased TMRE fluorescent intensity, cell cycle arrest at G₂/M and increased early and late apoptosis. Furthermore, fisetin treatment modulated pro-apoptotic genes such as APAF1, Bad, Bax, Bid and BIK at both transcript and protein levels and anti-apoptotic gene Bcl-2, BIRC8, MCL-1, XIAP/BIRC4, Livin/BIRC7, clap-2/BIRC3, etc. at protein levels to mitigate cell proliferation and induce apoptosis. Interestingly, the aforementioned alterations consequently led to an elevated level of Caspase-3, Caspase-8 and Caspase-9, which was found to be consistent with the transcript and protein level expression. Moreover, fisetin downregulated the expression of AKT and MAPK pathways to avert proliferation and enhance apoptosis of cancer cells. Fisetin treatment also improves oxidative stress and alleviates inflammation by regulating JAK-STAT/NF-kB pathways. Conclusion: Together, these studies established that fisetin deters human cervical cancer cell proliferation, enhances apoptosis and ameliorates inflammation through regulating various signalling pathways that may be used as a therapeutic regime for better cancer management.

Antiangiogenic Phytochemicals Constituent of Diet as Promising Candidates for Chemoprevention of Cancer

Despite the extensive knowledge on cancer nature acquired over the last years, the high incidence of this disease evidences a need for new approaches that complement the clinical intervention of tumors. Interestingly, many types of cancer are closely related to dietary habits associated with the Western lifestyle, such as low fruit and vegetable intake. Recent advances around the old-conceived term of chemoprevention highlight the important role of phytochemicals as good candidates for the prevention or treatment of cancer. The potential to inhibit angiogenesis exhibited by many natural compounds constituent of plant foods makes them especially interesting for their use as chemopreventive agents. Here, we review the antitumoral potential, with a focus on the antiangiogenic effects, of phenolic and polyphenolic compounds, such as quercetin or myricetin; terpenoids, such as ursolic acid or kahweol; and anthraquinones from Aloe vera, in different in vitro and in vivo assays, and the available clinical data. Although clinical trials have failed to assess the preventive role of many of these compounds, encouraging preclinical data support the efficacy of phytochemicals constituent of diet in the prevention and treatment of cancer, but a deeper understanding of their mechanisms of action and better designed clinical trials are urgently needed.

Identification of Inhibitory Activities of Dietary Flavonoids against URAT1, a Renal Urate Re-Absorber: In Vitro Screening and Fractional Approach Focused on Rooibos Leaves

Hyperuricemia, a lifestyle-related disease characterized by elevated serum urate levels, is the main risk factor for gout; therefore, the serum urate-lowering effects of human diets or dietary ingredients have attracted widespread interest. As Urate transporter 1 (URAT1) governs most urate reabsorption from primary urine into blood, URAT1 inhibition helps decrease serum urate levels by increasing the net renal urate excretion. In this study, we used a cell-based urate transport assay to investigate the URAT1-inhibitory effects of 162 extracts of plant materials consumed by humans. Among these, we focused on Aspalathus linearis, the source of rooibos tea, to explore its active ingredients. Using liquid–liquid extraction with subsequent column chromatography, as well as spectrometric analyses for chemical characterization, we identified quercetin as a URAT1 inhibitor. We also investigated the URAT1-inhibitory activities of 23 dietary ingredients including nine flavanols, two flavanonols, two flavones, two isoflavonoids, eight chalcones, and a coumarin. Among the tested authentic chemicals, fisetin and quercetin showed the strongest and second-strongest URAT1-inhibitory activities, with IC₅₀ values of 7.5 and 12.6 μM, respectively. Although these effects of phytochemicals should be investigated further in human studies, our findings may provide new clues for using nutraceuticals to promote health.

Angioprevention of Urologic Cancers by Plant-Derived Foods

The number of cancer cases worldwide keeps growing unstoppably, despite the undeniable advances achieved by basic research and clinical practice. Urologic tumors, including some as prevalent as prostate, bladder or kidney tumors, are no exceptions to this rule. Moreover, the fact that many of these tumors are detected in early stages lengthens the duration of their treatment, with a significant increase in health care costs. In this scenario, prevention offers the most cost-effective long-term strategy for the global control of these diseases. Although specialized diets are not the only way to decrease the chances to develop cancer, epidemiological evidence support the role of certain plant-derived foods in the prevention of urologic cancer. In many cases, these plants are rich in antiangiogenic phytochemicals, which could be responsible for their protective or angiopreventive properties. Angiogenesis inhibition may contribute to slow down the progression of the tumor at very different stages and, for this reason, angiopreventive strategies could be implemented at different levels of chemoprevention, depending on the targeted population. In this review, epidemiological evidence supporting the role of certain plant-derived foods in urologic cancer prevention are presented, with particular emphasis on their content in bioactive phytochemicals that could be used in the angioprevention of cancer.

Fisetin Ameliorates Alcohol-Induced Liver Injury through Regulating SIRT1 and SphK1 Pathway

Alcoholic liver disease (ALD) often leads to hepatitis, hepatic cirrhosis, and even hepatocellular carcinoma. Fisetin has been shown to confer protection against liver injury. Herein, we investigated whether fisetin could prevent ethanol-induced hepatotoxicity. Mice were fed on 5% (v/v) Lieber–DeCarli ethanol diet. Human primary hepatic stellate cells (HSCs) co-cultured with ethanol were used to verify the therapeutic effect of fisetin. The results of alanine/aspartate aminotransferase (ALT/AST), Triglyceride (TG), total cholesterol (TC) in serum, Oil O Red and Masson staining revealed that fisetin (80[Formula: see text]mg/kg) ameliorated ethanol-induced mice liver injury and fibrosis. Besides, immunofluorescence results of [Formula: see text]-SMA revealed that fisetin suppressed HSCs activation. The suppression was dose-dependent. Furthermore, fisetin promoted SIRT1-mediated autophagy and inhibited Sphk1-mediated endoplasmic reticulum stress (ER stress) both in vitro and in vivo. Molecular docking results indicated potential interaction of fisetin with SIRT1 and SphK1. The inhibitory effect of fisetin on HSCs activation was reversed on co-culturing with EX-527, a specific inhibitor against STIR1 overexpression. Thus, fisetin has the potential to ameliorate alcohol-induced liver injury through suppression of HSCs activation, SIRT1-mediated autophagy and Sphk1-mediated ER stress.

Cellular Senescence: Mechanisms and Therapeutic Potential

Cellular senescence is a complex and multistep biological process which cells can undergo in response to different stresses. Referring to a highly stable cell cycle arrest, cellular senescence can influence a multitude of biological processes-both physiologically and pathologically. While phenotypically diverse, characteristics of senescence include the expression of the senescence-associated secretory phenotype, cell cycle arrest factors, senescence-associated β-galactosidase, morphogenesis, and chromatin remodelling. Persistent senescence is associated with pathologies such as aging, while transient senescence is associated with beneficial programmes, such as limb patterning. With these implications, senescence-based translational studies, namely senotherapy and pro-senescence therapy, are well underway to find the cure to complicated diseases such as cancer and atherosclerosis. Being a subject of major interest only in the recent decades, much remains to be studied, such as regarding the identification of unique biomarkers of senescent cells. This review attempts to provide a comprehensive understanding of the diverse literature on senescence, and discuss the knowledge we have on senescence thus far.

Recent advances in the discovery of senolytics

The demonstration in model organisms that cellular senescence drives aging and age-related diseases has led to widespread efforts to identify compounds able to selectively kill senescent cells, termed senolytics. Approaches used to identify senolytics include bioinformatic analysis of senescent cell anti-apoptotic pathways (SCAPs) for drug development and screening of drugs libraries on different senescent cell types in culture. Alternatively, cytotoxic compounds can be made specific to senescent cells through a prodrug strategy such as linking the compound to a galactose moiety where toxicity is activated by lysosomal β-galactosidase. Identified senolytics can then be optimized through medicinal chemistry or linking to E3 targeting moieties to facilitate proteolysis of their targets. This review will provide an overview of approaches to identify senolytics and an update of the classes of senolytics identified to date.

Fisetin Inhibits NLRP3 Inflammasome by Suppressing TLR4/MD2-Mediated Mitochondrial ROS Production

Fisetin has numerous therapeutic properties, such as anti-inflammatory, antioxidative, and anticancer effects. However, the mechanism by which fisetin inhibits NLRP3 inflammasome remains unclear. In this study, we observed that fisetin bound to TLR4 and occluded the hydrophobic pocket of MD2, which in turn inhibited the binding of LPS to the TLR4/MD2 complex. This prevented the initiation of scaffold formation by the inhibition of MyD88/IRAK4 and subsequently downregulated the NF-κB signaling pathway. The result also demonstrated that fisetin downregulated the activation of the NLRP3 inflammasome induced by LPS and ATP (LPS/ATP) and the subsequent maturation of IL-1β. Fisetin also activated mitophagy and prevented the accumulation of damaged mitochondria and the excessive production of mitochondrial reactive oxygen species. The transient knockdown of p62 reversed the inhibitory activity of fisetin on the LPS/ATP-induced formation of the NLRP3 inflammasome. This indicated that fisetin induces p62-mediated mitophagy for eliminating damaged mitochondria. Recently, the existence of inflammasomes in non-mammalian species including zebrafish have been identified. Treatment of an LPS/ATP-stimulated zebrafish model with fisetin aided the recovery of the impaired heart rate, decreased the recruitment of macrophage to the brain, and gradually downregulated the expression of inflammasome-related genes. These results indicated that fisetin inhibited the TLR4/MD2-mediated activation of NLRP3 inflammasome by eliminating damaged mitochondria in a p62-dependent manner.

Current Insight into the Therapeutic Potential of Phytocompounds and their Nanoparticle-based Systems for Effective Management of Lung Cancer

Lung cancer is the second most common cancer and the primary cause of cancer-related death in both men and women worldwide. Due to diagnosis at an advanced stage, it is associated with high mortality in the majority of patients. At present, various treatment approaches are available such as chemotherapy, surgery, and radiotherapy. However, all these approaches usually cause serious side effects like degeneration of normal cells, bone marrow depression, alopecia, extensive vomiting, etc. To overcome the aforementioned problems, researchers have focused on the alternative therapeutic approach in which various natural compounds are reported, which possessed anti-lung cancer activity. Phytocompounds exhibit their anti-lung cancer activity via targeting various cell-signaling pathways, apoptosis, cell cycle arrest, and regulating antioxidant status and detoxification. Apart from the excellent anti-cancer activity, clinical administration of phytocompounds is confined because of their high lipophilicity and low bioavailability. Therefore, researchers show their concern in the development of a stable, safe, and effective approach of treatment with minimal side effects by the development of nanoparticle-based delivery of these phytocompounds to the target site. Targeted delivery of phytocompound through nanoparticles overcomes the aforementioned problems. In this article, the molecular mechanism of phytocompounds, their emerging combination therapy, and their nanoparticles-based delivery systems in the treatment of lung cancer have been discussed.

Natural-Derived Molecules as a Potential Adjuvant in Chemotherapy: Normal Cell Protectors and Cancer Cell Sensitizers

BACKGROUND

Cancer is a global threat to humans and a leading cause of death worldwide. Cancer treatment includes, among other things, the use of chemotherapeutic agents, compounds that are vital for treating and preventing cancer. However, chemotherapeutic agents produce oxidative stress along with other side effects that would affect the human body.

OBJECTIVE

To reduce the oxidative stress of chemotherapeutic agents in cancer and normal cells by naturally derived compounds with anti-cancer properties, and protect normal cells from the oxidation process. Therefore, the need to develop more potent chemotherapeutics with fewer side effects has become increasingly important.

METHOD

Recent literature dealing with the antioxidant and anticancer activities of the naturally naturally-derived compounds: morin, myricetin, malvidin, naringin, eriodictyol, isovitexin, daidzein, naringenin, chrysin, and fisetin has been surveyed and examined in this review. For this, data were gathered from different search engines, including Google Scholar, ScienceDirect, PubMed, Scopus, Web of Science, Scopus, and Scifinder, among others. Additionally, several patient offices such as WIPO, CIPO, and USPTO were consulted to obtain published articles related to these compounds.

RESULT

Numerous plants contain flavonoids and polyphenolic compounds such as morin, myricetin, malvidin, naringin, eriodictyol, isovitexin, daidzein, naringenin, chrysin, and fisetin, which exhibit ‎antioxidant, anti-inflammatory, and anti-carcinogenic actions via several mechanisms. These compounds show sensitizers of cancer cells and protectors of healthy cells. Moreover, these compounds can reduce oxidative stress, which is accelerated by chemotherapeutics and exhibit a potent anticancer effect on cancer cells.

CONCLUSIONS

Based on these findings, more research is recommended to explore and evaluate such flavonoids and polyphenolic compounds.

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 Interaction of the Flavonoid Fisetin with Human Glutathione Transferase A1-1

Glutathione transferases (GSTs) are a family of Phase II detoxification enzymes that are involved in the development of the multidrug resistance (MDR) mechanism in cancer cells and therefore affect the clinical outcome of cancer chemotherapy. The discovery of nontoxic natural compounds as inhibitors for GSTs is a promising approach for chemosensitizing and reversing MDR. Fisetin (7,3′,4′-flavon-3-ol) is a plant flavonol present in many plants and fruits. In the present work, the interaction of fisetin with human glutathione transferase A1-1 (hGSTA1-1) was investigated. Kinetic analysis revealed that fisetin is a reversible inhibitor for hGSTA1-1 with IC₅₀ 1.2 ± 0.1 μΜ. It functions as a mixed-type inhibitor toward glutathione (GSH) and as a noncompetitive inhibitor toward the electrophile substrate 1-chloro-2,4-dinitrobenzene (CDNB). In silico molecular modeling and docking predicted that fisetin binds at a distinct location, in the solvent channel of the enzyme, and occupies the entrance of the substrate-binding sites. Treatment of proliferating human epithelial colorectal adenocarcinoma cells (CaCo-2) with fisetin causes a reduction in the expression of hGSTA1-1 at the mRNA and protein levels. In addition, fisetin inhibits GST activity in CaCo-2 cell crude extract with an IC₅₀ (2.5 ± 0.1 μΜ), comparable to that measured using purified recombinant hGSTA1-1. These actions of fisetin can provide a synergistic role toward the suppression and chemosensitization of cancer cells. The results of the present study provide insights into the development of safe and effective GST-targeted cancer chemosensitizers.

Fisetin inhibits tau aggregation by interacting with the protein and preventing the formation of β-strands

Alzheimer's disease is a neurodegenerative disease which severely impacts the health of the elderly. Current treatments are only able to alleviate symptoms, but not prevent or cure the disease. The neurofibrillary tangles formed by tau protein aggregation are one of the defining characteristics of Alzheimer's disease, so tau protein has become a key target for the drug design. In this study, we show that fisetin, a plant-derived polyphenol compound, can inhibit aggregation of the tau fragment, K18, and can disaggregate tau K18 filaments in vitro. Meanwhile it is able to prevent the formation of tau aggregates in cells. Both experimental and computational studies indicate that fisetin could directly interact with tau K18 protein. The binding is mainly created by hydrogen bond and van der Waal force, prevents the formation of β-strands at the two hexapeptide motifs, and does not perturb the secondary structure or the tubulin binding ability of tau protein. In summary, fisetin might be a candidate for further development as a potential preventive or therapeutic drug for Alzheimer's disease.

A bird's eye view of the advanced approaches and strategies for overshadowing triple negative breast cancer

Triple negative breast cancer (TNBC) is one of the most aggressive form of breast cancer. It is characterized by the absence of estrogen, progesterone and human epidermal growth factor receptors. The main issue with TNBC is that it exhibits poor prognosis, high risk of relapse, short progression-free survival and low overall survival in patients. This is because the conventional therapy used for managing TNBC has issues pertaining to poor bioavailability, lower cellular uptake, increased off-target effects and development of resistance. To overcome such pitfalls, several other approaches are explored. In this context, the present manuscript showcases three of the most widely used approaches which are (i) nanotechnology-based approach; (ii) gene therapy approach and (iii) Phytochemical-based approach. The ultimate focus is to present and explain the insightful reports based on these approaches. Further, the review also expounds on the identified molecular targets and novel targeting ligands which are explored for managing TNBC effectively. Thus, in a nutshell, the review tries to highlight these existing treatment approaches which might inspire for future development of novel therapies with a potential of overshadowing TNBC.

New tricks of old drugs: Repurposing non-chemo drugs and dietary phytochemicals as adjuvants in anti-tumor therapies

Combination therapy has long been applied to enhance therapeutic effect and deal with the occurrence of multi-drug resistance in cancer treatment. However, the overlapping toxicity of multiple anticancer drugs to healthy tissues and increasing financial burden on patients emerged as major concerns. As promising alternatives to chemo agents, repurposed non-chemo drugs and dietary phytochemicals have been investigated as adjuvants to conventional anti-tumor therapeutics, offering a safe and economic strategy for combination therapy. In this review, we aim to highlight the advances in research about combination therapy using conventional therapeutics and repurposed drugs or phytochemicals for an enhanced anti-tumor efficacy, along with the mechanisms involved in the synergism. Beyond these, we outlined the potential challenges and solutions for clinical translation of the proposed combination therapy, providing a safe and affordable strategy to improve the reach of cancer therapy to low income regions with such new tricks of old drugs.