Quercetin metabolites inhibit MMP-2 expression in A549 lung cancer cells by PPAR-γ associated mechanisms

Harnessing the capacity of phytochemicals to enhance immune checkpoint inhibitor therapy of cancers: A focus on brain malignancies

Brain cancers, particularly glioblastoma multiforme (GBM), are challenging health issues with frequent unmet aspects. Today, discovering safe and effective therapeutic modalities for brain tumors is among the top research interests. Immunotherapy is an emerging area of investigation in cancer treatment. Since immune checkpoints play fundamental roles in repressing anti-cancer immunity, diverse immune checkpoint inhibitors (ICIs) have been developed, and some monoclonal antibodies have been approved clinically for particular cancers; nevertheless, there are significant concerns regarding their efficacy and safety in brain tumors. Among the various tools to modify the immune checkpoints, phytochemicals show good effectiveness and excellent safety, making them suitable candidates for developing better ICIs. Phytochemicals regulate multiple immunological checkpoint-related signaling pathways in cancer biology; however, their efficacy for clinical cancer immunotherapy remains to be established. Here, we discussed the involvement of immune checkpoints in cancer pathology and summarized recent advancements in applying phytochemicals in modulating immune checkpoints in brain tumors to highlight the state-of-the-art and give constructive prospects for future research.

Cold atmospheric plasma attenuates skin cancer via ROS induced apoptosis

BACKGROUND

Cold atmospheric plasma (CAP) has been widely used in biomedical research, especially in vitro cancer therapy. Cutaneous squamous cell carcinoma (CSCC) is a malignant tumor originating from epidermal keratinocytes. However, the mechanism of CAP therapy on CSCC remains unclear.

METHODS AND RESULTS

The animal models of CSCC induced by 7,12-dimethylbenz(a) anthracene (DMBA)/12-O-tetradecanoylphorbol-13-acetate (TPA) were constructed. For the CAP treatment group, after each TPA application, CAP was administered for 3 min twice weekly after drying. HE staining were used to detect the pathological status of tumor tissue in each group. The levels of PCNA, Bcl-2, Bax, MMP2 and MMP9 were evaluated by western blot and qPCR. TUNEL staining were used to detect apoptosis in tumor tissues. In vivo, serum samples were used for ELISA of total ROS. MTT assay was used to detect the viability of A431 cells. Western blot and qPCR were used to detect the levels of PCNA, Bcl-2, Bax, MMP2 and MMP9 in A431 cells. A431 cell proliferation was examined by colony formation assay. The proportions of apoptosis of A431 cells were detected by flow cytometry. Transwell assessed the ability of A431 cells migration and proliferation. We found that CAP could induce skin cancer cells apoptosis and inhibit the progress of skin cancer. Through experiments in vitro, reactive oxygen species (ROS) generated by N-acetylcysteine (NAC) and CAP inhibited the proliferation and migration of A431 skin cancer cells while promoting apoptosis.

CONCLUSIONS

These evidences suggest the protective effect of CAP in CSCC, and CAP has the potential clinical application of CSCC.

Enhancing effect of the coexisting alpha-tocopherol on quercetin absorption and metabolism

The aim of this study is to investigate the modulating effect of coexisting food components on the absorption and metabolism of quercetin and blood plasma antioxidant potentials. The combination of quercetin with α-tocopherol (αT), cellulose, or a commercially available vegetable beverage containing αT and dietary fiber was orally administered to mice. Compared to the single administration of quercetin aglycone, the coadministration of αT with quercetin significantly increased the plasma quercetin concentration at 0.5 h, whereas the combination of quercetin and cellulose decreased it. Interestingly, the administration of quercetin mixed with the vegetable beverage showed no significant change in the quercetin concentration in the mice plasma. The treatment of the cells with the blood plasma after the coadministration of αT with quercetin significantly upregulated the gene expression of the antioxidant enzyme (heme oxygenase-1), whereas the quercetin and cellulose combination did not. In the plasma of the quercetin-administered mice, eight types of quercetin metabolites were detected, and their quantities were affected by the combination with αT. The potentials of the heme oxygenase-1 gene expression by these metabolites were very limited, although several metabolites showed radical scavenging activities comparable to aglycone in the in vitro assays. These results suggested that the combination of αT potentiates the quercetin absorption and metabolism and thus the plasma antioxidant potentials, at least in part, by the quantitative changes in the quercetin metabolites.

Preparation and characterization of lotus root starch based bioactive edible film containing quercetin-encapsulated nanoparticle and its effect on grape preservation

The present work aimed to develop a novel bioactive edible film prepared by adding quercetin-encapsulated carboxymethyl lotus root starch nanoparticles (QNPs)，gellan gum and lotus root starch. The physicochemical characteristics, preservation effect and mechanism on grapes of the prepared film were investigated. SEM results showed that QNPs (5 %) were dispersed uniformly within lotus root starch matrix, indicating the formation of a stable composite nanoparticle film. In addition, the incorporation of QNPs (5 %) effectively improved the mechanical strength, thermal stability, barrier property and antioxidant activity of QNPs/starch film. Moreover, compared with the control, the QNPs/starch (5 %) film showed effective preservation effect on grapes during 21 days of storage at room temperature, based on the characterization by grape appearance, weight loss, firmness, and titratable acidity. Further studies found that QNPs/starch (5 %) film could exhibit enhanced antioxidant activity and potent anti-fungal ability against Botrytis cinerea, thus extending grape shelf life. In conclusion, the obtained QNPs/starch (5 %) film presented a promising application as an edible packing material for fruit preservation by antioxidant and preventing Botrytis cinerea contamination.

Inhibiting G6PD by quercetin promotes degradation of EGFR T790M mutation

EGFRT790M mutation causes resistance to the first-generation tyrosine kinase inhibitors (TKIs) in patients with non-small cell lung cancer (NSCLC). However, the therapeutic options for sensitizing first TKIs and delaying the emergence of EGFRT790M mutant are limited. In this study, we show that quercetin directly binds with glucose-6-phosphate dehydrogenase (G6PD) and inhibits its enzymatic activity through competitively abrogating NADP+ binding in the catalytic domain. This inhibition subsequently reduces intracellular NADPH levels, resulting in insufficient substrate for methionine reductase A (MsrA) to reduce M790 oxidization of EGFRT790M and inducing the degradation of EGFRT790M. Quercetin synergistically enhances the therapeutic effect of gefitinib on EGFRT790M-harboring NSCLCs and delays the acquisition of the EGFRT790M mutation. Notably, high levels of G6PD expression are correlated with poor prognosis and the emerging time of EGFRT790M mutation in patients with NSCLC. These findings highlight the potential implication of quercetin in overcoming EGFRT790M-driven TKI resistance by directly targeting G6PD.

Involvement of the peroxisome proliferator-activated receptor gamma (Pparγ) and matrix metalloproteinases-2 and -9 (Mmp-2 and -9) in the mechanism of action of di(2-ethylhexyl)phthalate (DEHP) in cultured mouse brain astrocytes and neurons

Di(2-ethylhexyl)phthalate (DEHP) is one of the most widely used phthalates in industry. It has been shown that, after entering the body, DEHP has the ability to cross the blood-placenta and blood-brain barriers. One of the proposed mechanisms of action of DEHP is the activation of peroxisome proliferator-activated receptors (PPARs). Many different functions of PPARγ in cells have been demonstrated, one of which is the modulation of the activation of matrix metalloproteinases (MMPs). The aim of this study was to investigate the role of Pparγ, Mmp-2, and Mmp-9 in the mechanism of action of DEHP. The experiments were performed on in vitro primary murine neurons and astrocytes. The results showed that DEHP has a pro-apototic effect on neurons, causing an increase in caspase-3 activity and in the number of apoptotic bodies. However, in astrocytes, the increase in caspase-3 activity was not related to the apoptosis process, as no increase in the formation of apoptotic bodies was observed. Moreover, DEHP increased the proliferation of astrocytes, which was confirmed by the increase in the amount and expression of the Ki-67 protein. In astrocytes, DEHP decreased the expression of the Pparγ and Mmp-9 proteins but increased the expression of the Mmp-2 protein. In DEHP neurons, it increased the expression of the Pparγ protein but decreased the expression of the Mmp-2 and Mmp-9 proteins.

Design, Synthesis, and Biological Evaluation of Novel Quercetin Derivatives as PPAR-γ Partial Agonists by Modulating Epithelial-Mesenchymal Transition in Lung Cancer Metastasis

Epithelial-to-mesenchymal transition (EMT) is responsible for driving metastasis of multiple cancer types including lung cancer. Peroxisome proliferator-activated receptor (PPAR)-γ, a ligand-activated transcription factor, controls expression of variety of genes involved in EMT. Although several synthetic compounds act as potent full agonists for PPAR-γ, their long term application is restricted due to serious adverse effects. Therefore, partial agonists involving reduced and balanced PPAR-γ activity are more effective and valued. A previous study discerned the efficacy of quercetin and its derivatives to attain favorable stabilization with PPAR-γ. Here this work is extended by synthesizing five novel quercetin derivatives (QDs) namely thiosemicarbazone (QUETSC)) and hydrazones (quercetin isonicotinic acid hydrazone (QUEINH), quercetin nicotinic acid hydrazone (QUENH), quercetin 2-furoic hydrazone (QUE2FH), and quercetin salicyl hydrazone (QUESH)) and their effects are analyzed in modulating EMT in lung cancer cell lines via PPAR-γ partial activation. QDs-treated A549 cells diminish cell proliferation strongly at nanomolar concentration compared to NCI-H460 cells. Of the five screened derivatives, QUETSC, QUE2FH, and QUESH exhibit the property of partial activation as compared to the overexpressive level of rosiglitazone. Consistently, these QDs also suppress EMT process by markedly downregulating the levels of mesenchymal markers (Snail, Slug, and zinc finger E-box binding homeobox 1) and concomitant upregulation of epithelial marker (E-cadherin).

Nano Drug Delivery Strategies for an Oral Bioenhanced Quercetin Formulation

Quercetin, a naturally occurring flavonoid, has been credited with a wide spectrum of therapeutic properties. However, the oral use of quercetin is limited due to its poor water solubility, low bioavailability, rapid metabolism, and rapid plasma clearance. Quercetin has been studied extensively when used with various nanodelivery systems for enhancing quercetin bioavailability. To enhance its oral bioavailability and efficacy, various quercetin-loaded nanosystems such as nanosuspensions, polymer nanoparticles, metal nanoparticles, emulsions, liposomes or phytosomes, micelles, solid lipid nanoparticles, and other lipid-based nanoparticles have been investigated in in-vitro cells, in-vivo animal models, and humans. Among the aforementioned nanosystems, quercetin phytosomes are attracting more interest and are available on the market. The present review covers insights into the possibilities of harnessing quercetin for several therapeutic applications and a special focus on anticancer applications and the clinical benefits of nanoquercetin formulations.

The potential anti-cancer effects of quercetin on blood, prostate and lung cancers: An update

Cancer is caused by abnormal proliferation of cells and aberrant recognition of the immune system. According to recent studies, natural products are most likely to be effective at preventing cancer without causing any noticeable complications. Among the bioactive flavonoids found in fruits and vegetables, quercetin is known for its anti-inflammatory, antioxidant, and anticancer properties. This review aims to highlight the potential therapeutic effects of quercetin on some different types of cancers including blood, lung and prostate cancers.

PPAR-γ Partial Agonists in Disease-Fate Decision with Special Reference to Cancer

Peroxisome proliferator-activated receptor-γ (PPAR-γ) has emerged as one of the most extensively studied transcription factors since its discovery in 1990, highlighting its importance in the etiology and treatment of numerous diseases involving various types of cancer, type 2 diabetes mellitus, autoimmune, dermatological and cardiovascular disorders. Ligands are regarded as the key determinant for the tissue-specific activation of PPAR-γ. However, the mechanism governing this process is merely a contradictory debate which is yet to be systematically researched. Either these receptors get weakly activated by endogenous or natural ligands or leads to a direct over-activation process by synthetic ligands, serving as complete full agonists. Therefore, fine-tuning on the action of PPAR-γ and more subtle modulation can be a rewarding approach which might open new avenues for the treatment of several diseases. In the recent era, researchers have sought to develop safer partial PPAR-γ agonists in order to dodge the toxicity induced by full agonists, akin to a balanced activation. With a particular reference to cancer, this review concentrates on the therapeutic role of partial agonists, especially in cancer treatment. Additionally, a timely examination of their efficacy on various other disease-fate decisions has been also discussed.

Impact of Phytochemicals on PPAR Receptors: Implications for Disease Treatments

Peroxisome proliferator-activated receptors (PPARs) are members of the ligand-dependent nuclear receptor family. PPARs have attracted wide attention as pharmacologic mediators to manage multiple diseases and their underlying signaling targets. They mediate a broad range of specific biological activities and multiple organ toxicity, including cellular differentiation, metabolic syndrome, cancer, atherosclerosis, neurodegeneration, cardiovascular diseases, and inflammation related to their up/downstream signaling pathways. Consequently, several types of selective PPAR ligands, such as fibrates and thiazolidinediones (TZDs), have been approved as their pharmacological agonists. Despite these advances, the use of PPAR agonists is known to cause adverse effects in various systems. Conversely, some naturally occurring PPAR agonists, including polyunsaturated fatty acids and natural endogenous PPAR agonists curcumin and resveratrol, have been introduced as safe agonists as a result of their clinical evidence or preclinical experiments. This review focuses on research on plant-derived active ingredients (natural phytochemicals) as potential safe and promising PPAR agonists. Moreover, it provides a comprehensive review and critique of the role of phytochemicals in PPARs-related diseases and provides an understanding of phytochemical-mediated PPAR-dependent and -independent cascades. The findings of this research will help to define the functions of phytochemicals as potent PPAR pharmacological agonists in underlying disease mechanisms and their related complications.

Systematic characterization of Puerariae Flos metabolites in vivo and assessment of its protective mechanisms against alcoholic liver injury in a rat model

Puerariae Flos, a representative homology plant of medicine and food for alcoholism, has a long history of clinical experience and remarkable curative effect in the treatment of alcoholic liver disease (ALD). However, its effective forms and hepatoprotective mechanisms remain unknown. In the present study, a strategy based on UPLC-QTOF MS combined with mass defect filtering technique was established for comprehensive mapping of the metabolic profile of PF in rat plasma, urine, bile, and feces after oral administration. Furthermore, the absorbed constituents into plasma and bile with a relatively high level were subjected to the network analysis, functional enrichment analysis, and molecular docking to clarify the potential mechanism. Finally, the therapeutic effect of PF on ALD and predicted mechanisms were further evaluated using a rat model of alcohol-induced liver injury and Western blot analysis. In total, 25 prototype components and 82 metabolites, including 93 flavonoids, 13 saponins, and one phenolic acid, were identified or tentatively characterized in vivo. In addition, glucuronidation, sulfation, methylation, hydroxylation, and reduction were observed as the major metabolic pathways of PF. The constructed compound–target–pathway network revealed that 11 absorbed constituents associated with the 16 relevant targets could be responsible for the protective activity of PF against ALD by regulating nine pathways attributable to glycolysis/gluconeogenesis, amino acid metabolism, and lipid regulation as well as inflammation and immune regulation. In addition, four active ingredients (6″-O-xylosyltectoridin, genistein-7-glucuronide-4′-sulfate, tectoridin-4′-sulfate, and 6″-O-xylosyltectoridin-4′-sulfate) as well as two target genes (MAO-A and PPAR-α) were screened and validated to play a crucial role with a good molecular docking score. The present results not only increase the understanding on the effective form and molecular mechanisms of PF-mediated protection against ALD but also promote better application of PF as a supplement food and herbal medicine for the treatment of ALD.

A New Risk Model Based on 7 Quercetin-Related Target Genes for Predicting the Prognosis of Patients With Lung Adenocarcinoma

Background: Studies have reported that quercetin inhibits the growth and migration of lung adenocarcinoma (LUAD). This study aimed to explore the roles and mechanisms of quercetin target genes in the progression of LUAD.

Methods: The quercetin structure and potential target genes of quercetin were explored in the Traditional Chinese Medicine Systems Pharmacology and SwissTargetPrediction databases. The differentially expressed quercetin target genes were identified in The Cancer Genome Atlas (TCGA) database, and the clinical values of quercetin target genes were explored. Subsequently, a risk model was constructed via the Cox regression and survival analysis to evaluate the potential effects and possible mechanisms of quercetin target genes.

Results: The quercetin differential target genes involved in biological processes such as the oxidation-reduction process, cell proliferation, G2/M transition of the mitotic cell cycle, and were related to the lung cancer. NEK2, TOP2A, PLK1, CA4, CDK5R1, AURKB, and F2 were related to the prognosis, and were independent factors influencing the prognosis of LUAD patients. The risk model was related to the gender, clinical stage, T stage, lymph node metastasis, and survival status of LUAD patients, and was independent risk factor associated with poor prognosis. In the high-risk group, the risk model involved signaling pathways such as cell cycle, DNA replication, spliceosome, and homologous recombination.

Conclusion: The quercetin potential target genes NEK2, TOP2A, PLK1, CA4, CDK5R1, AURKB, and F2 were related to the diagnosis and prognosis of LUAD patients. A risk model based on 7 quercetin target genes could be used to assess the prognosis of patients with LUAD.

Targeted delivery of quercetin by biotinylated mixed micelles for non-small cell lung cancer treatment

Lung cancer is the leading cause of cancer death world-wide and its treatment remains a challenge in clinic, especially for non-small cell lung cancer (NSCLC). Thus, more effective therapeutic strategies are required for NSCLC treatment. Quercetin (Que) as a natural flavonoid compound has gained increasing interests due to its anticancer activity. However, poor water solubility, low bioavailability, short half-life, and weak tumor accumulation hinder in vivo applications and antitumor effects of Que. In this study, we developed Que-loaded mixed micelles (Que-MMICs) assembled from 1,2-distearoyl-sn-glycero-3-phosphoethanolamine–poly(ethylene glycol)–biotin (DSPE–PEG–biotin) and poly(ethylene glycol) methyl ether methacrylate–poly[2-(dimethylamino) ethyl acrylate]–polycaprolactone (PEGMA–PDMAEA–PCL) for NSCLC treatment. The results showed that Que was efficiently encapsulated into the mixed micelles and the encapsulation efficiency (EE) was up to 85.7%. Cellular uptake results showed that biotin conjugation significantly improved 1.2-fold internalization of the carrier compared to that of non-targeted mixed micelles. In vitro results demonstrated that Que-MMICs could improve cytotoxicity (IC₅₀ = 7.83 μg/mL) than Que-MICs (16.15 μg/mL) and free Que (44.22 μg/mL) to A549 cells, which efficiently induced apoptosis and arrested cell cycle. Furthermore, Que-MMICs showed satisfactory tumor targeting capability and antitumor efficacy possibly due to the combination of enhanced permeability and retention (EPR) and active targeting effect. Collectively, Que-MMICs demonstrated high accumulation at tumor site and exhibited superior anticancer activity in NSCLC bearing mice model.

Quercetin Enhances the Suppressive Effects of Doxorubicin on the Migration of MDA-MB-231 Breast Cancer Cell Line

Background: Cancer cell metastasis is facilitated by matrix-metalloproteinases through degradation of extracellular matrix (ECM) proteins and is a major cause of mortality. One of the most common remedies for cancer is chemotherapy, which has many side effects. Therefore, it seems necessary to find a way to reduce the side effects of these drugs while maintaining their anticancer effects. Quercetin (que) is a natural substance that has been reported to have anticancer activities. Objectives: This study aims at evaluating the effect of que in combination with doxorubicin (dox) on the migration of the MDA-MB-231 breast cancer cell line. Methods: The effects of que and dox on cell viability in 24h and 48 h was assessed by MTT assay. Also, the effects of the same drugs on the cancer cells migration were evaluated, using the wound healing assay. Lastly, the effects of que and dox were assessed on the expression of MMP-2 and MMP-9 genes. Results: The combination of 50 µM of que with 32 nM of dox was selected by CI comparison. The viability and migration of cancer cells and the gelatinases genes expression were decreased after treatment with individual drugs. The migration and the expression of MMP-2 and MMP-9 genes after treatment with the combination of que and dox was significantly reduced compared to the treatment with que and dox alone. Conclusions: Que inhibits the viability and migration of MDA-MB-231 cancer cells and synergistically enhances the effects of dox on the survival and migration of these cells. Hence, we propose this drug combination as a path for further research on breast cancer therapy.

Anethum sowa Roxb. ex fleming: A review on traditional uses, phytochemistry, pharmacological and toxicological activities

ETHNOPHARMACOLOGICAL RELEVANCE

Anethum sowa Roxb. ex Fleming (Syn. Peucedanum sowa Roxb. ex Fleming, Family: Apiaceae) is a pharmacologically important as aromatic and medicinal plant. Various parts of this plant are used in traditional medicine systems for carminative, uterine and colic pain, digestion disorder, flatulence in babies, appetite-stimulating agent and used to treat mild flue and cough. The essential oil is used for aromatherapy. It is also used as a spice for food flavouring and culinary preparations in many Asian and European countries.

AIM OF THE REVIEW

This review aims to provide a comprehensive and critical assessment from the reported traditional and pharmaceutical uses and pharmacological activities of the extracts, essential oil and phytoconstituents with emphasis on its therapeutic potential as well as toxicological evaluation of A. sowa.

MATERIALS AND METHODS

Online search engines such as SciFinder®, GoogleScholar®, ResearchGate®, Web of Science®, Scopus®, PubMed and additional data from books, proceedings and local prints were searched using relevant keywords and terminologies related to A. sowa for critical analyses.

RESULTS

The literature studies demonstrated that A. sowa possesses several ethnopharmacological activities, including pharmaceutical prescriptions, traditional applications, and spice in food preparations. The phytochemical investigation conducted on crude extracts has been characterized and identified various classes of compounds, including coumarins, anthraquinone, terpenoids, alkaloid, benzodioxoles, phenolics, polyphenols, phenolic and polyphenols, fatty acids, phthalides and carotenoids. The extracts and compounds from the different parts of A. sowa showed diverse in vitro and in vivo biological activities including antioxidant, antiviral, antibacterial, analgesic and anti-inflammatory, Alzheimer associating neuromodulatory, cytotoxic, anticancer, antidiabetes, insecticidal and larvicidal.

CONCLUSION

A. sowa is a valuable medicinal plant which is especially used in food flavouring and culinary preparations. This review summarized the pertinent information on A. sowa and its traditional and culinary uses, as well as potential pharmacological properties of essential oils, extracts and isolated compounds. The traditional uses of A. sowa are supported by in vitro/vivo pharmacological studies; however, further investigation on A. sowa should be focused on isolation and identification of more active compounds and establish the links between the traditional uses and reported pharmacological activities with active compounds, as well as structure-activity relationship and in vivo mechanistic studies before integrated into the medicine. The toxicological report confirmed its safety. Nonetheless, pharmacokinetic evaluation tests to validate its bioavailability should be encouraged.

Growth Suppression in Lung Cancer Cells Harboring EGFR-C797S Mutation by Quercetin

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are approved treatments for non-small-cell lung cancer (NSCLC) patients harboring activating EGFR mutations. The EGFR C797S mutation is one of the known acquired-resistance mutations to the latest third-generation TKIs. At present, there are no clear options for treating patients who acquire resistance to third-generation TKIs. The acquisition of the EGFR C797S mutation was shown to upregulate the expression of AXL, a receptor tyrosine kinase of the TAM (TYRO3-AXL-MER) family, and the suppression of AXL is effective in reducing the growth of NSCLC cells harboring EGFR C797S. As quercetin was recently shown to inhibit AXL, quercetin may be effective in treating NSCLC cells harboring the EGFR C797S mutation. In this work, the cytotoxic effects of quercetin and its ability to inhibit tumor growth were examined in TKI-resistant NSCLC cells harboring the EGFR C797S mutation. We demonstrated that quercetin exhibited potent cytotoxic effects on NSCLC cells harboring the EGFR C797S mutation by inhibiting AXL and inducing apoptosis. Quercetin inhibited the tumor growth of xenografted NSCLC cells harboring the EGFR C797S mutation and appeared to act synergistically with brigatinib to inhibit of tumor growth in vivo. In summary, herein, we revealed that quercetin is an effective inhibitor for the treatment of non-small-cell lung cancer harboring the EGFR C797S mutation.

PPAR Gamma and Viral Infections of the Brain

Peroxisome Proliferator-Activated Receptor gamma (PPARγ) is a master regulator of metabolism, adipogenesis, inflammation and cell cycle, and it has been extensively studied in the brain in relation to inflammation or neurodegeneration. Little is known however about its role in viral infections of the brain parenchyma, although they represent the most frequent cause of encephalitis and are a major threat for the developing brain. Specific to viral infections is the ability to subvert signaling pathways of the host cell to ensure virus replication and spreading, as deleterious as the consequences may be for the host. In this respect, the pleiotropic role of PPARγ makes it a critical target of infection. This review aims to provide an update on the role of PPARγ in viral infections of the brain. Recent studies have highlighted the involvement of PPARγ in brain or neural cells infected by immunodeficiency virus 1, Zika virus, or human cytomegalovirus. They have provided a better understanding on PPARγ functions in the infected brain, and revealed that it can be a double-edged sword with respect to inflammation, viral replication, or neuronogenesis. They unraveled new roles of PPARγ in health and disease and could possibly help designing new therapeutic strategies.

Variation of PPARG Expression in Chemotherapy-Sensitive Patients of Hypopharyngeal Squamous Cell Carcinoma

Our previous study showed that the upregulation of peroxisome proliferator-activated receptor gamma (PPARG) could promote chemosensitivity of hypopharyngeal squamous cell carcinoma (HSCC) in chemotherapeutic treatments. Here, we acquired two more independent expression data of PPARG to validate the expression levels of PPARG in chemotherapy-sensitive patients (CSP) and its individualized variations compared to chemotherapy-non-sensitive patients (CNSP). Our results showed that overall PPARG expression was mildly downregulated (log fold change = −0.55; p value = 0.42; overexpression in three CSPs and reduced expression in four CSPs), which was not consistent with previous results (log fold change = 0.50; p = 0.22; overexpression in nine CSPs and reduced expression in three CSPs). Both studies indicated that PPARG expression variation was significantly associated with the Tumor-Node-Metastasis (TNM) stage (p = 7.45e − 7 and 6.50e − 4, for the first and second studies, respectively), which was used as one of the predictors of chemosensitivity. The new dataset analysis revealed 51 genes with significant gene expression changes in CSPs (LFC > 1 or <-1; p value < 0.01), and two of them (TMEM45A and RBP1) demonstrated strong coexpression with PPARG (Pearson correlation coefficient > 0.6 or <-0.6). There were 21 significant genes in the data from the first study, with no significant association with PPARG and no overlap with the 51 genes revealed in this study. Our results support the connection between PPARG and chemosensitivity in HSCC tumor cells. However, significant PPARG variation exists in CSPs, which may be influenced by multiple factors, including the TNM stage.

Effects of quercetin on cell differentiation and adipogenesis in 3T3-L1 adipocytes

BACKGROUND/OBJECTIVES

Adipocytes undergo angiogenesis to receive nutrients and oxygen needed for adipocyte' growth and differentiation. No study relating quercetin with angiogenesis in adipocytes exists. Therefore, this study investigated the role of quercetin on adipogenesis in 3T3-L1 cells, acting through matrix metalloproteinases (MMPs).

MATERIALS/METHODS

After proliferating preadipocytes into adipocytes, various quercetin concentrations were added to adipocytes, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays were performed to evaluate cell proliferation. Glycerol-3-phosphate dehydrogenase (GPDH) activity was investigated as an indicator of fat accumulation. The mRNA expressions of transcription factors related to adipocyte differentiation, CCAAT/enhancer-binding proteins (C/EBPs), peroxisomal proliferator-activated receptors (PPAR)-γ, and adipocyte protein 2 (aP2), were investigated. The mRNA expressions of proteins related to angiogenesis, vascular endothelial growth factor (VEGF)-α, vascular endothelial growth factor receptor (VEGFR)-2, MMP-2, and MMP-9, were investigated. Enzyme activities and concentrations of MMP-2 and MMP-9 were also measured.

RESULTS

Quercetin treatment suppressed fat accumulation and the expressions of adipocyte differentiation-related genes (C/EBPα, C/EBPβ, PPAR-γ, and aP2) in a concentration-dependent manner in 3T3-L1 cells. Quercetin treatments reduced the mRNA expressions of VEGF-α, VEGFR-2, MMP-2, and MMP-9 in 3T3-L1 cells. The activities and concentrations of MMP-2 and MMP-9 were also decreased significantly as the concentration of quercetin increased.

CONCLUSIONS

The results confirm that quercetin inhibits adipose tissue differentiation and fat accumulation in 3T3-L1 cells, which could occur through inhibition of the angiogenesis process related to MMPs.

Probing intermolecular interactions and binding stability of kaempferol, quercetin and resveratrol derivatives with PPAR-γ: docking, molecular dynamics and MM/GBSA approach to reveal potent PPAR- γ agonist against cancer

Peroxisome Proliferator-Activated Receptors-γ (PPAR-γ), a ligand-activated transcription factor, suggested having anti-inflammatory effects by activating the target genes when bound to the ligand. Herein, we examined a conformational analysis of 8708 derivatives of Kaempferol, Quercetin, and Resveratrol, the prime activators of PPAR-γ molecular target by employing molecular docking and dynamic simulation pipeline to screen out potential agonists. The structure-based docking procedure performed by FlexX tool shortlisted high binding affinities of these derivatives of Kaempferol, Quercetin and Resveratrol with the protein receptor with a score of -38.94 kcal/mol (4'-Carboxy-5, 7-Dihydroxyflavone-CDHF), -41.63 kcal/mol (Demethyltorosaflavone D- DMTF) and -31.52 kcal/mol (Resveratrol-O-disulphate- RD) respectively, signifying the selected derivatives forms interactions like H-bond, Aromatic H-Bond, Pi-Pi stacking and salt bridges with PPAR-γ. The PPAR-γ-derivative complex was stabilized by intermolecular hydrogen bonds and stacking interactions. A greater interaction was significantly observed between the binding affinities of derivatives compared to the standards. Based on the root mean square deviation (RMSD) and root mean square fluctuation (RMSF) carried by the means of high-speed molecular dynamics (MD) and simulation of best-docked poses, the ligand, DMTF attained the most favored interaction with PPAR-γ. Thus, it appeared to have high chemical scaffold diversity and may confer high drug-likeness. The binding free energy (ΔG) led us to manifest Quercetin derivative to have a key role for PPAR-γ receptor. The result obtained clearly indicates the exploitation of the promising new drug leads that may further influence in synthesizing and analyzing the development as anti-cancer agonists.Communicated by Ramaswamy H. Sarma.

Biosynthesis of bioactive tamarixetin in recombinant Escherichia coli

Tamarixetin, a monomethylated derivative of quercetin, has been reported to possess many important biological activities. In the present study, a whole cell biotransformation system was used for regiospecific methylation of quercetin to produce 4'-O-methylated quercetin (tamarixetin) using methyltransferase from Streptomyces sp. KCTC 0041BP in Escherichia coli Bl21 (DE3). Its production was enhanced by adding a plasmid containing S-adenosine-l-methionine (SAM) synthase from E. coli K12 (MetK) with subsequent feeding of l-methionine and glycerol in the culture. The best condition produced ∼279 μM (88.2 mg/L) of tamarixetin. The biological activity of tamarixetin was tested and compared with quercetin, 7-O-methylated quercetin, and 3-O-methylated quercetin. Results showed that the growth of all tested cancer cell lines (AGS, B16F10, C6, and HeLa) were inhibited by tamarixetin more effectively than other methylated derivatives of quercetin or quercetin. Tamarixetin also exhibited the best antimelanogenic activity among all compounds tested.

Inhibition of matrix metalloproteinases: a troubleshooting for dentin adhesion

Matrix metalloproteinases (MMPs) are enzymes that can degrade collagen in hybrid layer and reduce the longevity of adhesive restorations. As scientific understanding of the MMPs has advanced, useful strategies focusing on preventing these enzymes' actions by MMP inhibitors have quickly developed in many medical fields. However, in restorative dentistry, it is still not well established. This paper is an overview of the strategies to inhibit MMPs that can achieve a long-lasting material-tooth adhesion. Literature search was performed comprehensively using the electronic databases: PubMed, ScienceDirect and Scopus including articles from May 2007 to December 2019 and the main search terms were “matrix metalloproteinases”, “collagen”, and “dentin” and “hybrid layer”. MMPs typical structure consists of several distinct domains. MMP inhibitors can be divided into 2 main groups: synthetic (synthetic-peptides, non-peptide molecules and compounds, tetracyclines, metallic ions, and others) and natural bioactive inhibitors mainly flavonoids. Selective inhibitors of MMPs promise to be the future for specific targeting of preventing dentin proteolysis. The knowledge about MMPs functionality should be considered to synthesize drugs capable to efficiently and selectively block MMPs chemical routes targeting their inactivation in order to overcome the current limitations of the therapeutic use of MMPs inhibitors, i.e., easy clinical application and long-lasting effect.

Development of stimuli-responsive intelligent polymer micelles for the delivery of doxorubicin

Doxorubicin is still used as a first-line drug in current therapeutics for numerous types of malignant tumours (including lymphoma, transplantable leukaemia and solid tumour). Nevertheless, to overcome the serious side effects like cardiotoxicity and myelosuppression caused by effective doses of doxorubicin remains as a world-class puzzle. In recent years, the usage of biocompatible polymeric nanomaterials to form an intelligently sensitive carrier for the targeted release in tumour microenvironment has attracted wide attention. These different intelligent polymeric micelles (PMs) could change the pharmacokinetics process of drugs or respond in the special microenvironment of tumour site to maximise the efficacy and reduce the toxicity of doxorubicin in other tissues and organs. Several intelligent PMs have already been in the clinical research stage and planned for market. Therefore, related research remains active, and the latest nanotechnology approaches for doxorubicin delivery are always in the spotlight. Centring on the model drugs doxorubicin, this review summarised the mechanisms of PMs, classified the polymers used in the application of doxorubicin delivery and discussed some interesting and imaginative smart PMs in recent years.

Pparg may Promote Chemosensitivity of Hypopharyngeal Squamous Cell Carcinoma

The upregulation of peroxisome proliferator-activated receptor gamma (PPARG) has been shown to increase the chemosensitivity of several human cancers. This study is aimed at studying if PPARG sensitizes hypopharyngeal squamous cell carcinoma (HSCC) in chemotherapeutic treatments and at dissecting possible mechanisms of observed effects. We integrated large-scale literature data and HSCC gene expression data to identify regulatory pathways that link PPARG and chemosensitivity in HSCC. Expression levels of molecules within the PPARG regulatory pathways were compared in 21 patients that underwent chemotherapy for primary HSCC, including 12 chemotherapy-sensitive patients (CSP) and 9 chemotherapy-nonsensitive patients (CNSP). In the CPS group, expression levels of PPARG were higher than that in the CNSP group (log‐fold‐change = 0.50). Structured text mining identified two chemosensitivity-related regulatory pathways driven by PPARG. In the CSP group, expression levels for 7 chemosensitivity-promoting genes were increased, while for 13 chemosensitivity suppressing the gene expression levels were decreased. Our results support the chemosensitivity-promoting role of PPARG in HSCC tumor cells, most likely by affecting both cell proliferation and cell motility pathways.

Alpinumisoflavone suppresses human Glioblastoma cell growth and induces cell cycle arrest through activating peroxisome proliferator-activated receptor-γ

As a common subtype of malignant gliomas, glioblastoma multiforme (GBM) is associated with poor prognosis. This study is aimed to examine the anticancer activities of alpinumisoflavone (AIF) and its underlying mechanisms. Our results demonstrated that AIF inhibited the proliferation of GBM cells (U373 and T98G) in a time and dose-dependent manner. In addition, flow cytometry analysis not only confirmed AIF arrested cell cycle at the G0/G1 phase but also the induced apoptosis of U373 and T98G cells. Western blotting also confirmed that AIF altered the expression levels of cell cycle-related proteins. Further mechanism studies revealed that AIF inhibited cell proliferation, induced G0/G1 phase arrest and induced apoptosis of U373 and T98G cells through activating PPARγ, as evidenced by the fact that GW9662 (PPARγ inhibitor) could effectively reverse the effects of AIF on U373 and T98G cells. Furthermore, the in vivo study also revealed that AIF suppressed tumor growth and caused cell cycle arrest. Collectively, these results highlighted the potential use of AIF in the treatment of GBM.

Association between obesity and breast cancer: Molecular bases and the effect of flavonoids in signaling pathways

Obesity is an abnormal or excessive accumulation of fat that leads to different health problems, such as cancer, where the adipocytes promote the proliferation, migration, and invasion of cancer cells, especially in the breast, where the epithelial cells are immersed in a fatty environment, and the interactions between these two types of cells involve, not only adipokines but also local pro-inflammatory mechanisms and hypoxic processes generating anti-apoptotic signals, which are a common result in leptin signaling. The expression of the Vascular Endothelial Growth Factor (VEGF) and cyclin D1, results in the decrease in phosphorylation of AMPK, increasing the activity of the aromatase enzyme; alternatively, the adiponectin activates AMPK to reduce inflammation. Nevertheless, alterations of the JAK/STAT pathways contribute to mammary carcinogenesis, while the PI3K/AKT/mTOR pathway controls most of the cancer's characteristics such as the cell cycle, survival, differentiation, proliferation, motility, metabolism, and genetic stability. Therefore, the purpose of the present review is, through the accumulated scientific evidence, to find the concordance between the signaling pathways involved among obesity and breast cancer, which can be modulated by using flavonoids.

Systems Pharmacology Uncovers Multiple Mechanisms of Erxian Decoction () for Treatment of Premature Ovarian Failure

OBJECTIVE

To predict the chemical compositions and drug targets and to systematically dissect the pharmacological mechanism of Erxian Decoction (, EXD) as a treatment for premature ovarian failure (POF) using a systems pharmacology approach.

METHODS

The compounds present in EXD were obtained from three databases. The active ingredient was identified by analyzing the values of oral bioavailability (OB), drug-likeness (DL), and Lipinski's rule (LR). The active ingredients were further searched in research articles, drug targets in the DrugBank database, and the C-T and T-P networks, as well as by pathway analysis using the Cytoscape platform.

RESULTS

A total of 728 compounds were identified in EXD. Of these, 59 were identified as active compounds that conformed to the criteria with OB ⩾30% and DL ⩾0.18. By further searches in the literature, 126 related targets were identified that could interact with the active compounds. Additionally, it was found that the beneficial effects of EXD in POF are probably exerted via regulation of the immune system, modulation of estrogen levels, and anti-oxidative activities, and that it may act in a synergistic or cooperative manner with other therapeutic agents.

CONCLUSIONS

The systems pharmacology approach is a comprehensive system that was used to elucidate the pharmacological mechanism of EXD as a treatment for POF. The results of this study will also facilitate the application of traditional medicine in modern treatment strategies.

Role of Key Micronutrients from Nutrigenetic and Nutrigenomic Perspectives in Cancer Prevention

Regarding cancer as a genetic multi-factorial disease, a number of aspects need to be investigated and analyzed in terms of cancer's predisposition, development and prognosis. One of these multi-dimensional factors, which has gained increased attention in the oncological field due to its unelucidated role in risk assessment for cancer, is diet. Moreover, as studies advance, a clearer connection between diet and the molecular alteration of patients is becoming identifiable and quantifiable, thereby replacing the old general view associating specific phenotypical changes with the differential intake of nutrients. Respectively, there are two major fields concentrated on the interrelation between genome and diet: nutrigenetics and nutrigenomics. Nutrigenetics studies the effects of nutrition at the gene level, whereas nutrigenomics studies the effect of nutrients on genome and transcriptome patterns. By precisely evaluating the interaction between the genomic profile of patients and their nutrient intake, it is possible to envision a concept of personalized medicine encompassing nutrition and health care. The list of nutrients that could have an inhibitory effect on cancer development is quite extensive, with evidence in the scientific literature. The administration of these nutrients showed significant results in vitro and in vivo regarding cancer inhibition, although more studies regarding administration in effective doses in actual patients need to be done.

Antiasthmatic activity of quercetin glycosides in neonatal asthmatic rats

The present study investigated the anti-asthmatic activity of quercetin glycosides in neonatal asthmatic rats. Rats were divided into four groups: sham (non-asthmatic), asthmatic control, quercetin (25 mg/kg), and quercetin (50 mg/kg). Inflammatory cells in bronchoalveolar lavage fluid (BALF), inflammatory markers, apoptosis, fibrinogen level, prothrombin time, thrombin time, activated partial thromboplastin time, coagulation factor activity, and histopathology were monitored. Quercetin significantly reduced total leukocytes, eosinophils, tumor necrosis factor-α (TNF-α), interleukin (IL-6), nitric oxide (NO), and apoptosis. It also considerably reduced blood coagulation time and coagulation factor activity compared to the controls. The mRNA expression levels of TNF-α, IL-6, and inducible nitric oxide synthase (iNOS) were elevated in asthmatic rats by 1.3-, 1.04-, and 1.1-fold, respectively. However, treatment with 50 mg/kg quercetin glycosides significantly reduced the mRNA expression of TNF-α, IL-6, and iNOS by more than 40%. Quercetin considerably reduced the protein expression of iNOS. Airway and blood vessel narrowing, as well as the accumulation of eosinophils in the lungs were observed in neonatal asthmatic rats. However, treatment with quercetin glycosides significantly reduced inflammation and eosinophil infiltration. In summary, quercetin glycosides significantly attenuated levels of inflammatory markers, demonstrating its protective effects against neonatal asthma in rats.

Quercetin suppresses the proliferation and metastasis of metastatic osteosarcoma cells by inhibiting parathyroid hormone receptor 1

Osteosarcoma is an aggressive malignant neoplasm and cancerous bone tumor. Quercetin is a well-known flavonoid abundant in vegetables, fruits, grains, leaves, and red onions. In the present study, we evaluated the effects of quercetin-induced inhibition of parathyroid hormone receptor 1 (PTHR1) on proliferation, migration, and invasion in U2OS and Saos^-2 cells. Following incubation with quercetin (20, 40, 60, 80, or 100 μM) for 48 h, the cell viability of U2OS and Saos^-2 cells were significantly reduced in a dose-dependent manner. Additionally, there were significant decreases in cell adhesion, invasion, and migration as well as reduced cell viability at higher concentrations of quercetin. Furthermore, the mRNA expression levels of matrix metalloproteinases (MMP)-2 and -9 were attenuated, whereas the mRNA expression levels of tissue inhibitors of metalloproteinases (TIMP)-1 and -2 were elevated. Quercetin treatment also significantly reduced the mRNA expression levels of PTHR1 by 0.27-, and 0.55-fold at 80, and 100 μM, respectively, whereas 0.19 and 0.41 folds in Saos^-2 cells. PTHR1 protein expression in U2OS cells was reduced by 0.19-, and 0.43-fold at 80, and 100 μM of quercetin, respectively (P < 0.05), whereas 0.17 and 0.35 folds in Saos-2 cells. Immunofluorescence analyses revealed reduced expression of PTHR1 following treatment with quercetin. PTHR1 expression in U2OS cells was reduced by 0.18-, and 0.41-fold at 80, and 100 μM, respectively, whereas 0.15 and 0.38 folds in Saos^-2 cells. The knockdown of PTHR1enhanced quercetin-inhibited proliferation and invasion. Taken together, the present findings indicate that quercetin reduced human metastatic osteosarcoma cell invasion, adhesion, proliferation, and migration by inhibiting PTHR1.

ESI-TOF MS analysis of complexes formed between quercetin and five metal ions in hot water and a study into their DNA cleavage activity

Quercetin is a flavonoid compound widely found in vegetables, fruits, and medicinal plants. It has carbonyl and phenolic hydroxyl groups in its structure that can easily form complexes with metal ions. In this study, we reacted quercetin in water at 95 °C with five metal trace elements commonly found in plants, namely calcium, magnesium, zinc, iron(III), and copper. Each supernatant was then examined by electrospray ionization-time-of-flight mass spectrometry (ESI-TOF MS). The results showed that quercetin can form complexes with Ca²⁺, Mg²⁺, Zn²⁺, and Cu²⁺ in ratios of 2:1, 3:1, and 3:2. Interestingly, after reaction with Fe³⁺ in water at 95 °C, not only can quercetin‑iron(III) complexes be formed in ratios of 2:1 and 3:1, but small amounts of quercetin‑iron(II) complexes can also be formed in the same ratios. Furthermore, DNA cleavage experiments showed that when acting alone, quercetin and Cu²⁺ have weak or no cleavage effects on DNA, but the complex formed after reaction in hot water cleaves DNA in a time- and concentration-dependent manner. These results indicate that complexes may form between quercetin and a variety of metal trace elements in a water decoction of plants, and that these metal complexes may be the material basis for the health-promoting and therapeutic effects of edible or medicinal plants.

Effects of Quercetin Metabolites on Triglyceride Metabolism of 3T3-L1 Preadipocytes and Mature Adipocytes

Quercetin (Q) has rapid metabolism, which may make it worthwhile to focus on the potential activity of its metabolites. Our aim was to evaluate the triglyceride-lowering effects of Q metabolites in mature and pre-adipocytes, and to compare them to those induced by Q. 3T3-L1 mature and pre-adipocytes were treated with 0.1, 1 and 10 µM of Q, tamarixetin (TAM), isorhamnetin (ISO), quercetin-3-O-glucuronide (3G), quercetin-3-O-sulfate (3S), as well as with 3S and quercetin-4-O-sulfate (4S) mixture (3S+4S). Triglyceride (TG) content in both cell types, as well as free fatty acid (FFA) and glycerol in the incubation medium of mature adipocytes were measured spectrophotometrically. Gene expression was assessed by RT-PCR. In mature adipocytes, Q decreased TG at 1 and 10 µM, 3S metabolite at 1 and 10 µM, and 3S+4S mixture at 10 µM. 3S treatment modified the glucose uptake, and TG assembling, but not lipolysis or apoptosis. During differentiation, only 10 µM of ISO reduced TG content, as did Q at physiological doses. In conclusion, 3S metabolite but not ISO, 3G, 4S and TAM metabolites can contribute to the in vivo delipidating effect of Q.

In vivo administration of quercetin ameliorates sperm oxidative stress, inflammation, preserves sperm morphology and functions in streptozotocin-nicotinamide induced adult male diabetic rats

INTRODUCTION

Diabetes mellitus (DM) has been associated with sperm damage. In view of the fact that quercetin possesses antioxidant and anti-inflammatory activities, this compound may help to protect sperm against damage in DM. In this study, in-vivo effects of quercetin on sperm parameters in DM were investigated.

MATERIAL AND METHODS

Quercetin (10, 25 and 50 mg/kg/b.w.) was given orally to streptozotocin-nicotinamide induced adult male diabetic rats for 28 days. Following treatment completion, rats were sacrificed and sperm were harvested from the cauda epididymis. Sperm count, motility, viability, hyperosmotic swelling (HOS) tail-coiled sperm and morphology were assessed. Levels of lipid peroxidation (LPO) and anti-oxidative enzymes (SOD, CAT and GPx) in sperm with and without H₂O₂ incubation were determined by biochemical assays. Expression levels of SOD, CAT and GPx mRNAs in sperm were evaluated by qPCR. Sperm DNA integrity was estimated by flow cytometry while expression levels of the inflammatory markers NF-κβ and TNF-α in sperm were determined by Western blotting.

RESULTS

In diabetic rats receiving quercetin, sperm count and motility, viability and HOS tail-coiled sperm increased (p < 0.05) while sperm with abnormal morphology decreased. Moreover, sperm SOD, CAT, GPx activities and their mRNA expression levels increased while sperm LPO, NF-κβ and TNF-α levels decreased. In normal and diabetic rat sperm incubated with H₂O₂, a further increase in MDA and further decreases in SOD, CAT and GPx were observed, and these were ameliorated by quercetin treatment.

CONCLUSIONS

In-vivo administration of quercetin to diabetic rats helps to ameliorate sperm damage and improves sperm morphology and functions in DM.

Vesicular systems employing natural substances as promising drug candidates for MMP inhibition in glioblastoma: A nanotechnological approach

Glioblastoma multiforme (GBM), one of the most lethal Brain tumors, characterized by its high invasive nature and increased mortality rates forms a major bottleneck in transport of therapeutics across the Blood Brain Barrier (BBB). Matrix metalloproteinases (MMPs) are classified as enzymes, which are found to be up regulated in the Glioma tumor microenvironment and thus can be considered as a target for inhibition for curbing GBM. Many chemotherapeutics and techniques have been employed for inhibiting MMPs till now but all of them failed miserably and were withdrawn in clinical trials due to their inability in restricting the tumor growth or increasing the overall survival rates. Thus, the quest for finding the suitable MMP inhibitor is still on and there is a critical need for identification of novel compounds which can alter the BBB permeability, restrain tumor growth and prevent tumor recurrence. Currently, naturally derived substances are gaining widespread attention as tumor inhibitors and many studies have been reported by far highlighting their importance in restricting MMP expression thus serving as chemotherapeutics for cancer due to their minimal toxicity. These substances may serve as probable candidates for inhibiting MMP expression in GBM. However, targeting and delivering the inhibitor to its target site is an issue that needs to be overcome in order to attain maximum specificity and sustained release. The birth of nanotechnology served as a boon in delivering drugs to the most complicated areas thus paving way for Nano drug delivery. An efficient Nano carrier with ability to cross the BBB and competently kill the Glioma cells forms the prerequisite for GBM chemotherapy. Vesicular drug delivery systems are one such class of carriers, which have the capacity to release the drug at a predetermined rate at the target site thus minimizing any undesirable side effects. Exploiting vesicular systems as promising Nano drug carriers to formulate naturally derived substances, that can bypass the BBB and act as an inhibitor against MMPs in GBM is the main theme of this review.

A Sterol from Soft Coral Induces Apoptosis and Autophagy in MCF-7 Breast Cancer Cells

The peroxisome proliferator-activated receptor γ (PPARγ) is a nuclear receptor that plays a key role in regulating cellular metabolism, and is a therapeutic target for cancer therapy. To search for potential PPARγ activators, a compound library comprising 11 marine compounds was examined. Among them, a sterol, 3β,11-dihydroxy-9,11-secogorgost-5-en-9-one (compound 1), showed the highest PPARγ activity with an IC₅₀ value of 8.3 μM for inhibiting human breast adenocarcinoma cell (MCF-7) growth. Western blotting experiments showed that compound 1 induces caspase activation and PARP cleavage. In addition, compound 1 modulated the expression of various PPARγ-regulated downstream biomarkers including cyclin D1, cyclin-dependent kinase (CDK)6, B-cell lymphoma 2 (Bcl-2), p38, and extracellular-signal-regulated kinase (ERK). Moreover, compound 1 increased reactive oxygen species (ROS) generation, upregulated the phosphorylation and expression of H2AX, and induced autophagy. Interestingly, pre-treatment with the autophagy inhibitor 3-methyladenine rescued cells from compound 1-induced growth inhibition, which indicates that the cytotoxic effect of compound 1 is, in part, attributable to its ability to induce autophagy. In conclusion, these findings suggest the translational potential of compound 1 in breast cancer therapy.

Anti-tumor effects of a nonsteroidal anti-inflammatory drug zaltoprofen on chondrosarcoma via activating peroxisome proliferator-activated receptor gamma and suppressing matrix metalloproteinase-2 expression

Surgical resection is the only treatment for chondrosarcomas, because of their resistance to chemotherapy and radiotherapy; therefore, additional strategies are crucial to treat chondrosarcomas. Peroxisome proliferator-activated receptor gamma (PPARγ) is a ligand-activated transcription factor, which has been reported as a possible therapeutic target in certain malignancies including chondrosarcomas. In this study, we demonstrated that a nonsteroidal anti-inflammatory drug, zaltoprofen, could induce PPARγ activation and elicit anti-tumor effects in chondrosarcoma cells. Zaltoprofen was found to induce expressions of PPARγ mRNA and protein in human chondrosarcoma SW1353 and OUMS27 cells, and induce PPARγ-responsible promoter reporter activities. Inhibitory effects of zaltoprofen were observed on cell viability, proliferation, migration, and invasion, and the activity of matrix metalloproteinase-2 (MMP2); these effects were dependent on PPARγ activation and evidenced by silencing PPARγ. Moreover, we showed a case of a patient with cervical chondrosarcoma (grade 2), who was treated with zaltoprofen and has been free from disease progression for more than 2 years. Histopathological findings revealed enhanced expression of PPARγ and reduced expression of MMP2 after administration of zaltoprofen. These findings demonstrate that zaltoprofen could be a promising drug against the malignant phenotypes in chondrosarcomas via activation of PPARγ and inhibition of MMP2 activity.

Exploring the Mechanism of Dangguiliuhuang Decoction Against Hepatic Fibrosis by Network Pharmacology and Experimental Validation

Dangguiliuhuang decoction (DGLHD) has been demonstrated to be effective in treating inflammatory, hepatic steatosis, and insulin resistance. In the study, we tried to elucidate the pharmacological efficacy and mechanism of DGLHD against liver fibrosis and predicate potential active ingredients and targets via network analysis and experimental validation. In the formula, we totally discovered 76 potential active ingredients like baicalein, berberine, and wogonin, and 286 corresponding targets including PTGS (prostaglandin-endoperoxide synthase) 2, PPAR (peroxisome proliferator-activated receptors) -γ, and NF-κB (nuclear factor-κB). Pathway and functional enrichment analysis of these putative targets indicated that DGLHD obviously influenced NF-κB and PPAR signaling pathway. Consistently, DGLHD downregulated levels of ALT (alanine transaminase) and AST (aspartate transaminase), reduced production of proinflammatory cytokines-TNF (tumor necrosis factor) -α and IL (Interleukin) -1β in serum and liver from mice with hepatic fibrosis, and inhibited hepatic stellate cell (HSC)-T6 cells proliferation. DGLHD decreased TGF (transforming growth factor) -β1 and α-SMA (smooth muscle actin) expression as well, maintained MMP (matrix metalloprotein) 13-TIMP (tissue inhibitor of metalloproteinases) 1 balance, leading to mitigated ECM (extracellular matrix) deposition in vivo and in vitro. Moreover, our experimental data confirmed that the alleviated inflammation and ECM accumulation were pertinent to NF-κB inhibition and PPAR-γ activation. Overall, our results suggest that DGLHD aims at multiply targets and impedes the progression of hepatic fibrosis by ameliorating abnormal inflammation and ECM deposition, thereby serving as a novel regimen for treating hepatic fibrosis in clinic.

Unravelling the role of fatty acid metabolism in cancer through the FOXO3-FOXM1 axis

Obesity and cachexia represent divergent states of nutritional and metabolic imbalance but both are intimately linked to cancer. There is an extensive overlap in their signalling pathways and molecular components involved such as fatty acids (FAs), which likely play a crucial role in cancer. Forkhead box (FOX) proteins are responsible of a wide range of transcriptional programmes during normal development, and the FOXO3-FOXM1 axis is associated with cancer initiation, progression and drug resistance. Free fatty acids (FFAs), FA synthesis and β-oxidation are associated with cancer development and progression. Meanwhile, insulin and some adipokines, that are up-regulated by FAs, are also involved in cancer development and poor prognosis. In this review, we discuss the role of FA metabolism in cancer and how FA metabolism integrates with the FOXO3-FOXM1 axis. These new insights may provide leads to better cancer diagnostics as well as strategies for tackling cancer development, progression and drug resistance.

Apo-10'-lycopenoic acid inhibits cancer cell migration and angiogenesis and induces peroxisome proliferator-activated receptor γ

SCOPE

We have previously shown that apo-10'-lycopenoic acid (ALA), a derivative of lycopene through cleavage by carotene-9',10'-oxygenase, inhibits tumor progression and metastasis in both liver and lung cancer animal models. The underlying mechanism remains unknown. We hypothesized that ALA inhibits cancer cell motility and angiogenesis by up-regulating peroxisome proliferator-activated receptor γ (PPARγ) which is involved in controlling angiogenesis, tumor progression and metastasis.

METHODS AND RESULTS

ALA treatment, in dose-dependent manner, was effective at inhibiting migration and invasion of liver and lung cancer cells (HuH7 and A549) in both Transwell and wound-healing models, as well as suppressing actin remodeling and ruffling/lamellipodia formation in HuH7 and immortalized lung BEAS-2B cells. ALA treatment resulted in suppression of angiogenesis in both tube formation and aortic ring assays and inhibition of matrix metalloproteinase-2 expression and activation in both HuH7 and A549 cells. Additionally, ALA dose-dependently increased the mRNA expression and protein levels of PPARγ in human THLE-2 liver cells.

CONCLUSION

ALA inhibits cancer cell motility and angiogenesis and induces PPARγ expression, which could be one of the potential mechanisms for ALA protecting against tumor progression.

Anti-metastatic effects of isolinderalactone via the inhibition of MMP-2 and up regulation of NM23-H1 expression in human lung cancer A549 cells

Metastatic lung cancer is a leading cause of mortality and has a mortality rate of ≥90%. Isolinderalactone (ILL) is a sesquiterpene lactone compound that has been used in traditional Chinese medicine. Research has demonstrated that ILL has anti-inflammatory and anti-proliferative properties; however, to the best of our knowledge, studies investigating whether ILL can inhibit lung cancer cell metastasis have not been conducted. In the present study, 1-10 µM ILL was applied in the culturing of the A549 lung cancer cell line to investigate the effects of ILL on the invasion and migration of lung cancer cells, including whether the possible mechanisms of ILL are associated with the expression of matrix metalloproteinase (MMP)-2 and NME/NM23 nucleoside diphosphate kinase 1 (NM23-H1) genes. The results of the present study indicated that ILL inhibited the invasion and migration of the A549 cancer cells and exhibited a dose-response association. ILL also significantly inhibited the protein expression and activity of MMP-2 (P<0.05), exhibiting a trend similar to that of its invasion- and migration-associated properties. Further research revealed that ILL significantly increased the expression of NM23-H1 protein and inhibited the expression of β-catenin protein (P<0.05). The results of the present study is, to the best of our knowledge, the first to confirm that ILL can inhibit the invasion and migration of A549 cancer cells, with the possible mechanisms potentially involving the inhibition of MMP-2 and β-catenin protein expression resulting from the up regulation of NM23-H1 expression.