Antitumor Effect of Inula viscosa Extracts on DMBA-Induced Skin Carcinoma Are Mediated by Proteasome Inhibition

Inula viscosa (L). Aiton leaves extract ameliorate arthritis by antioxidative and anti-inflammatory effects in formaldehyde-induced arthritis in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Inula viscosa (L.) Aiton is a traditional medicinal plant widely distributed and used in Mediterranean countries, its leaves are prepared by maceration to treat, rheumatic pain, inflammatory diseases, diabetes, anemia and cancer.

AIM OF THE STUDY

The present study purpose to investigate the anti-inflammatory efficacy of I. viscosa leaves methanol extract (IVME) at three different doses on formaldehyde-induced arthritis in NMRI albinos mice.

MATERIALS AND METHODS

Mice were divided into six groups (n = 6) as follows: normal control, disease control, Diclofenac group (10 mg/kg, p.o. daily) and three groups, daily treated with 50, 100 and 200 mg/kg IVME (p.o.); Formaldehyde models were obtained by a sub-plantar administration of 20 μl of formaldehyde (3.75% v/v) into the right hind paws of NMRI albino mice on 1st and 3rd days of the 10 experimental days. Joint diameter was measured, arthritis severity was evaluated by inhibition of paw edema, histological changes, synovial hyperplasia and immune cells infiltration was evaluated by histological and immunohistochemical analyses of CD3+, CD20+ and CD68+. Post-mitochondrial supernatants (PMS) from liver tissues homogenates were collected for the assessment of enzymatic and non-enzymatic antioxidants: Catalase (CAT) & Myeloperoxidase (MPO) activities, glutathione (GSH) and an oxidative stress biomarker (nitric-oxide (NO)) level.

RESULTS

Administration of I. visocsa (at low dose: 50 mg/kg) significantly (∗∗∗p < 0.001) ameliorated the induced arthritis severity, reduced hyperplasia of synovial membrane, bone erosion and immune cells infiltration (∗p < 0.05), resulted by restoration of paw diameter. It also decreased levels of NO (∗∗∗p < 0.001) and MPO activity (∗∗∗p < 0.001), and significantly restored GSH levels (∗p < 0.05) and CAT activity (∗∗∗p < 0.001) in liver tissues.

CONCLUSION

These findings suggest that I. viscosa leaves have an anti-arthritic property. Which is due to the combination of antioxidant activity regulating oxidative stress and anti-inflammatory effect by probably cytokines regulation.

Novel copper complex inhibits the proteasome in skin squamous cell carcinoma induced by DMBA in mice

The proteasomal system is becoming a target for the treatment of several diseases, especially in cancer therapy. The present study aims to develop a novel copper complex that inhibits the proteasome in skin squamous cell carcinoma. New molecules based on the copper complex were synthesized for the first time to assess their potential as proteasome inhibitors, specifically targeting squamous cell carcinoma induced by 7,12-dimethylbenz(a)anthracene (DMBA) in mouse models. Fourier Transform Infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), nuclear magnetic resonance (NMR), and energy dispersive X-ray analysis (EDX) were carried out to characterize this new copper complex. Notably, the presence of a papilloma (skin tumor) was confirmed by histopathological analysis. Subsequent investigation included the quantification of proteasome levels using a sandwich ELISA test, and the catalytic activity of the 20S proteasome was determined by measuring the fluorescence emitted after the cleavage of 7-amino-4-methylcoumarin (AMC). Hence, X-ray crystallography indicates that all Cu atoms are five-coordinated in a square-pyramidal configuration and biological activity of copper Schiff base complex, which exhibits high proteasome inhibitory activities with particular selectivity of β5 subunit. The pharmacokinetic properties (ADMET) of the copper complex named Cu(L1) showed encouraging results with very low toxicity, distribution, and absorption. Structure-activity relationship (SAR) information obtained from Cu(L1) demonstrated its selectivity and potent inhibition for β5 subunit. In this regard, this copper complex has emerged as a novel therapy for skin cancer.

Chemical Composition, Antioxidant Capacity, and Anticancerous Effects against Human Lung Cancer Cells of a Terpenoid-Rich Fraction of Inula viscosa

Inula viscosa is a widely used plant in traditional Mediterranean and Middle Eastern medicine for various illnesses. I. viscosa has been shown to have anticancer effects against various cancers, but its effects against lung cancer have been under limited investigation. At the same time, I. viscosa is rich in terpenoids whose anti-lung cancer effects have been poorly investigated. This study aimed to examine the potential anticancer properties of methanolic and aqueous extracts of stems and leaves of I. viscosa and its terpenoid-rich fraction against human lung cancer A549 cells. Results showed that the methanolic extracts of I. viscosa had significantly higher polyphenol and flavonoid content and radical scavenging capacity than the aqueous extracts. In addition, leaves methanolic extracts (IVLM) caused the highest reduction in viability of A549 cells among all the extracts. IVLM also reduced the viability of human ovarian SK-OV-3, breast MCF-7, liver HepG2, and colorectal HCT116 cancer cells. A terpenoid-rich I. viscosa fraction (IVL DCM), prepared by liquid-liquid separation of IVLM in dichloromethane (DCM), displayed a substantial reduction in the viability of A549 cells (IC50 = 27.8 ± 1.5 µg/mL at 48 h) and the panel of tested cancerous cell lines but was not cytotoxic to normal human embryonic fibroblasts (HDFn). The assessment of IVL DCM phytochemical constituents using GC-MS analysis revealed 21 metabolites, highlighting an enrichment in terpenoids, such as lupeol and its derivatives, caryophyllene oxide, betulin, and isopulegol, known to exhibit proapoptotic and antimetastatic functions. IVL DCM also showed robust antioxidant capacity and decent polyphenol and flavonoid contents. Furthermore, Western blotting analysis indicated that IVL DCM reduced proliferation (reduction of proliferation marker Ki67 and induction of proliferation inhibitor proteins P21 and P27), contaminant with P38 MAP kinase activation, and induced the intrinsic apoptotic pathway (P53/BCL2/BAX/Caspase3/PARP) in A549 cells. IVL DCM also reduced the migration of A549 cells, potentially by reducing FAK activation. Future identification of anticancer metabolites of IVL DCM, especially terpenoids, is recommended. These data place I. viscosa as a new resource of herbal anticancer agents.

In silico identification of 20S proteasome-β5 subunit inhibitors using structure-based virtual screening

Proteasome inhibitors have effective anti-tumor activity in cell culture and can induce apoptosis by interfering with the degradation of cell cycle proteins. 20S Proteasome is acknowledged to be a satisfactory target that has persistent properties against the human immune defense and is obligatory for the degradation of some vital proteins. This study aimed to identify potential inhibitors against 20S proteasome, specifically the β5 subunit, using structure-based virtual screening and molecular docking to reduce the number of ligands that should be eligible for experimental assays. A total of 4961 molecules with anticancer activity were screened from the ASINEX database. The filtered compounds that showed higher docking affinity were then used in more sophisticated molecular docking simulations with AutoDock Vina for validation. Finally, six drug molecules (BDE 28974746, BDE 25657353, BDE 29746159, BDD 27844484, BDE 29746109, and BDE 29746162) exhibited highly significant interactions compared to the positive controls were retained. Among these six molecules, three molecules (BDE 28974746, BDE 25657353, and BDD 27844484) showed high binding affinity and binding energy compared with Carfilzomib and Bortezomib. Molecular simulation and dynamics studies of the top three drug molecules in each case allowed us to draw further conclusions about their stability with the β5 subunit. Computed absorption, distribution, metabolism, excretion and toxicity studies on these derivatives showed encouraging results with very low toxicity, distribution, and absorption. These compounds may serve as potential hits for further biological evaluation in the development of new proteasome inhibitors.Communicated by Ramaswamy H. Sarma.

Chemical composition, biological activities, and molecular mechanism of Inula viscosa (L.) bioactive compounds: a review

Inula viscosa is an herbaceous plant mainly found in Mediterranean regions, predominantly, used in developing countries as a folk remedy for treating numerous diseases using different traditional methods of preparation that includes infusion, decoction, and external application. Researchers have been interested in studying the antioxidant, anti-inflammatory, antifungal, antibacterial, antidiabetic, and antitumor effects of I. viscosa extracts, due to its high countenance of bioactive molecules. The chemical studies of ethanol, methanol, chloroform, aqueous, petroleum ether, dichloromethane, and ethyl acetate extracts from different parts of I. viscosa, growing around the world, and analyzed by different analytical techniques allowed to isolate and identify a great number of secondary metabolites from terpenes, flavonoids, phenylpropanoids, and polyketides, and complementary in vitro and in vivo studies indicated the pharmacological activities of an isolated compound, a mixture, or the crude extract. I. viscosa extracts had a great in vivo potential reducing mice paw, ear, and the severity of pulmonary edema, and the occurrence of skin carcinoma growing; in vitro recent study results showed, in addition, the high antioxidant, α-glucosidase, and α-amylase inhibitory activity, and neuroprotectivity effects; a correlation with the in vivo studies confirming the anti-inflammatory and antitumor proprieties, elucidating some molecular mechanisms: showing that tomentosin reduced pro-inflammatory cytokine secretion (IFNγ, IL-1, IL-2, TNF-α, and IL-6) via the suppression of transcription factor NF-κB and MAP kinase (p38/JNK) activation, and that the two phenolic compounds banaxanthone E and paxanthone inhibited the antiapoptotic protein BCL-2, activating the apoptotic process leading to the antiproliferative effect.

Methanolic Extracts of D. viscosa Specifically Affect the Cytoskeleton and Exert an Antiproliferative Effect on Human Colorectal Cancer Cell Lines, According to Their Proliferation Rate

Numerous studies have reported the pharmacological effects exhibited by Dittrichia viscosa, (D. viscosa) including antioxidant, cytotoxic, antiproliferative, and anticancer properties. In our research, our primary objective was to validate a prescreening methodology aimed at identifying the fraction that demonstrates the most potent antiproliferative and anticancer effects. Specifically, we investigated the impact of various extract fractions on the cytoskeleton using a screening method involving transgenic plants. Tumors are inherently heterogeneous, and the components of the cytoskeleton, particularly tubulin, are considered a strategic target for antitumor agents. To take heterogeneity into account, we used different lines of colorectal cancer, specifically one of the most common cancers regardless of gender. In patients with metastasis, the effectiveness of chemotherapy has been limited by severe side effects and by the development of resistance. Additional therapies and antiproliferative molecules are therefore needed. In our study, we used colon-like cell lines characterized by the expression of gastrointestinal differentiation markers (such as the HT-29 cell line) and undifferentiated cell lines showing the positive regulation of epithelial-mesenchymal transition and TGFβ signatures (such as the DLD-1, SW480, and SW620 cell lines). We showed that all three of the D. viscosa extract fractions have an antiproliferative effect but the pre-screening on transgenic plants anticipated that the methanolic fraction may be the most promising, targeting the cytoskeleton specifically and possibly resulting in fewer side effects. Here, we show that the preliminary use of screening in transgenic plants expressing subcellular markers can significantly reduce costs and focus the advanced characterization only on the most promising therapeutic molecules.

Functional and quantitative evaluation of the 20S proteasome in serum and intracellular in145 moroccan patients with hematologic malignancies

BACKGROUND

Regulatory degradation of intracellular proteins plays an essential role in most biological processes, particularly in the control of cell proliferation and differentiation. In eukaryotes, intracellular proteolysis is largely provided by the Ubiquitin / Proteasome system. Alterations and dysfunction of protein degradation by the Ubiquitin / Proteasome system, such as transcription factors, cell cycle regulators or tumor suppressor proteins, have been linked to human. Pathologies, including blood cancers. Mainly localized in the nucleus and cytoplasm of cells, the proteasome can be detected in the cell culture supernatant or in the peripheral blood of patients. This study deals with the problems of the search for serum markers specific to certain pathologies and which would be useful in the prevention, diagnosis and monitoring of cancers and which could be used as a therapeutic tool.

METHODS

The functional and quantitative analysis of the proteasome is carried out at the serum and subcellular level during a pathological phenomenon in a population of 145 Moroccan patients (sex ratio: 1.10 / average age: 47.9 ± 15, 3 years) using an indirect ELISA test and a follow-up of the fluorescence emitted after enzymatic digestion of specific peptides by proteolytic activity (chymotrypsin-like).

RESULTS

The evolutionary trend proteasome subcellular is significantly linked to the rate of chymotrypsin-like activity. The entire population of 60 patients called back for a second blood test. After three months of treatment reported a significant drop in the rate and the activity of the proteasome in serum and intracellular level.

CONCLUSIONS

Although the serum proteasome level is a potential new tool for the monitoring of. Patientswithliquid cancer.

TRIAL REGISTRATION

retrospectively registered.

Antineoplastic Properties by Proapoptotic Mechanisms Induction of Inula viscosa and Its Sesquiterpene Lactones Tomentosin and Inuviscolide

Cancer is a complex disease including approximately 200 different entities that can potentially affect all body tissues. Among the conventional treatments, radiotherapy and chemotherapy are most often applied to different types of cancers. Despite substantial advances in the development of innovative antineoplastic drugs, cancer remains one of the most significant causes of death, worldwide. The principal pitfall of successful cancer treatment is the intrinsic or acquired resistance to therapeutic agents. The development of more effective or synergistic therapeutic approaches to improve patient outcomes and minimize toxicity has become an urgent issue. Inula viscosa is widely distributed throughout Europe, Africa, and Asia. Used as a medicinal plant in different countries, I. viscosa has been characterized for its complex chemical composition in order to identify the bioactive compounds responsible for its biological activities, including anticancer effects. Sesquiterpene lactones (SLs) are natural, biologically active products that have attracted considerable attention due to their biological activities. SLs are alkylating agents that form covalent adducts with free cysteine residues within enzymes and key proteins favoring cancer cell cytotoxicity. They are effective inducers of apoptosis in several cancer cell types through different molecular mechanisms. This review focuses on recent advances in the cytotoxic effects of I. viscosa and SLs in the treatment of neoplastic diseases, with a special emphasis on their proapoptotic molecular mechanisms.

Antioxidant Activities and Mechanisms of Tomentosin in Human Keratinocytes

Tomentosin, one of natural sesquiterpene lactones sourced from Inula viscosa L., exerts therapeutic effects in various cell types. Here, we investigated the antioxidant activities and the underlying action mechanisms of tomentosin in HaCaT cells (a human keratinocyte cell line). Specifically, we examined the involvement of tomentosin in aryl hydrocarbon receptor (AhR) and nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathways. Treatment with tomentosin for up to 60 min triggered the production of reactive oxygen species (ROS), whereas treatment for 4 h or longer decreased ROS production. Tomentosin treatment also induced the nuclear translocation of Nrf2 and upregulated the expression of Nrf2 and its target genes. These data indicate that tomentosin induces ROS production at an early stage which activates the Nrf2 pathway by disrupting the Nrf2–Keap1 complex. However, at a later stage, ROS levels were reduced by tomentosin-induced upregulation of antioxidant genes. In addition, tomentosin induced the phosphorylation of mitogen-activated protein kinases (MAPKs) including p38 MAPK and c-Jun N-terminal kinase (JNK). SB203580 (a p38 MAPK inhibitor) and SP600125 (a JNK inhibitor) attenuated the tomentosin-induced phosphorylation of Nrf2, suggesting that JNK and p38 MAPK signaling pathways can contribute to the tomentosin-induced Nrf2 activation through phosphorylation of Nrf2. Furthermore, N-acetyl-_L-cysteine (NAC) treatment blocked both tomentosin-induced production of ROS and the nuclear translocation of Nrf2. These data suggest that tomentosin-induced Nrf2 signaling is mediated both by tomentosin-induced ROS production and the activation of p38 MAPK and JNK. Moreover, tomentosin inhibited the AhR signaling pathway, as evidenced by the suppression of xenobiotic-response element (XRE) reporter activity and the translocation of AhR into nucleus induced by urban pollutants, especially benzo[a]pyrene. These findings suggest that tomentosin can ameliorate skin damage induced by environmental pollutants.

Clarifying the molecular mechanism of tomentosin‑induced antiproliferative and proapoptotic effects in human multiple myeloma via gene expression profile and genetic interaction network analysis

Multiple myeloma (MM) is an aggressive B cell malignancy. Substantial progress has been made in the therapeutic context for patients with MM, however it still represents an incurable disease due to drug resistance and recurrence. Development of more effective or synergistic therapeutic approaches undoubtedly represents an unmet clinical need. Tomentosin is a bioactive natural sesquiterpene lactone extracted by various plants with therapeutic properties, including anti‑neoplastic effects. In the present study, the potential antitumor activity of tomentosin was evaluated on the human RPMI‑8226 cell line, treated with increasing tomentosin concentration for cytotoxicity screening. The data suggested that both cell cycle arrest and cell apoptosis could explain the antiproliferative effects of tomentosin and may result in the inhibition of RPMI‑8226 cell viability. To assess differentially expressed genes contributing to tomentosin activity and identify its mechanism of action, a microarray gene expression profile was performed, identifying 126 genes deregulated by tomentosin. To address the systems biology and identify how tomentosin deregulates gene expression in MM from a systems perspective, all deregulated genes were submitted to enrichment and molecular network analysis. The Protein‑Protein Interaction (PPI) network analysis showed that tomentosin in human MM induced the downregulation of genes involved in several pathways known to lead immune‑system processes, such as cytokine‑cytokine receptor interaction, chemokine or NF‑κB signaling pathway, as well as genes involved in pathways playing a central role in cellular neoplastic processes, such as growth, proliferation, migration, invasion and apoptosis. Tomentosin also induced endoplasmic reticulum stress via upregulation of cyclic AMP‑dependent transcription factor ATF‑4 and DNA damage‑inducible transcript 3 protein genes, suggesting that in the presence of tomentosin the protective unfolded protein response signaling may induce cell apoptosis. The functional connections analysis executed using the Connectivity Map tool, suggested that the effects of tomentosin on RPMI‑8226 cells might be similar to those exerted by heat shock proteins inhibitors. Taken together, these data suggested that tomentosin may be a potential drug candidate for the treatment of MM.

Anticancer and Anti-Inflammatory Effects of Tomentosin: Cellular and Molecular Mechanisms

Tomentosin is a natural compound known for its presence in some medicinal plants of the Asteraceae family such as Inula viscosa. Recent studies have highlighted its anticancer and anti-inflammatory properties. Its anticancer mechanisms are unique and act at different levels ranging from cellular organization to molecular transcriptional factors and epigenetic modifications. Tomentosin’s possession of the modulatory effect on telomerase expression on tumor cell lines has captured the interest of researchers and spurred a more robust study on its anticancer effect. Since inflammation has a close link with cancer disease, this natural compound appears to be a potential cancer-fighting drug. Indeed, its recently demonstrated anti-inflammatory action can be considered as a starting point for its evaluation as an anticancer chemo-preventive agent

The role of the ubiquitin-proteasome pathway in skin cancer development: 26S proteasome-activated NF-κB signal transduction

The Ubiquitin-Proteasome System plays a central role in signal transduction associated with stress, in the skin in particular by the control of NF-κB pathways. Under normal conditions, the inhibitory protein IκB is phosphorylated by kinases, then ubiquitinated and ends up at the proteasome to be degraded. The present short review discusses recent progress in the inhibition of NF-κB activation by proteasome inhibitors prevents the degradation of protein IκB, which accumulates in the cytosol, and there by the activation of NF-κB. Moreover, would not only limit the expression of adhesion molecules and cytokines involved in metastatic processes, but also increase the sensitivity of cancer cells to apoptosis. Considering this fact, the activity of NF-κB is regulated by the phosphorylation and proteasome-dependent degradation of its inhibitor Iκb. In this scenario, the use of a proteasome inhibitor might be an effective strategy in the treatment of skin cancer with constitutive activation of NF-κB.