Exploratory evaluation supported by experimental and modeling approaches of Inula viscosa root extract as a potent corrosion inhibitor for mild steel in a 1 M HCl solution.

The corrosion of metals poses a threat to the economy, the environment, and human health due to undesirable reactions and contaminated products. Corrosion inhibitors, including natural products, can play a key role in protecting metallic materials, especially under challenging conditions. In this study, the roots of the Inula viscosa plant were examined for their ability to act as corrosion inhibitors in a 1 M hydrochloric acid (HCl) solution. Different extracts of the plant were evaluated for their corrosion inhibition capacity in a 1 M HCl solution. The effectiveness of different plant extracts was assessed, including an aqueous extract, an ethanolic extract, and a combined water-ethanol extract. Compounds present in the roots of Inula viscosa were identified using high-performance liquid chromatography. The electrochemical properties of the extracts were studied using various techniques such as open circuit potential, electrochemical impedance spectroscopy, and potentiodynamic polarization. Additionally, surface analysis after immersion was performed using scanning electron microscopy. Electrochemical data revealed that Inula viscosa root (IVR) extracts acted as mixed-type corrosion inhibitors with pronounced cathodic characteristics. The inhibitory efficiency was closely related to the concentration of Inula viscosa (I. viscosa), showing a significant increase with higher concentrations. This resulted in a decrease in corrosion current and an increase in polarization resistance. Notably, inhibitory efficiency reached high levels, up to 97.7% in mixed extract which represents a mixture between water and ethanol. In our study, it was observed that the mixed extract (water + ethanol) allowed for a greater corrosion inhibition compared to the other solvents studied, 97.7%. Surface analyses confirmed the formation of an organic film layer on the steel surface, attributed to the bonding of functional groups and heteroatoms in I. viscosa components. Therefore, this study paves the way for the potential integration of I. viscosa as a promising corrosion inhibition material, offering durable protection against steel corrosion and opening avenues for various related applications.

Ultrasonic extraction of Inula viscosa: Enhancing antioxidant bioactivity and its application in sunflower oil as an antioxidant.

The objective of this study was to optimize the ultrasound-assisted extraction (UAE) of Inula viscosa, focusing on the extraction yield, total phenolic content (TPC), total flavonoid content (TFC), and antioxidant capacity and to evaluate its antioxidant effect in sunflower oil (SFO) storage. A water-ethanol binary solvent system was applied to extract bioactive components sustainably. Extraction parameters (temperature, time, ethanol concentration, and solvent-to-solid ratio) were optimized using a central composite rotatable design, achieving high accuracy (R2 > 0.974). Optimum conditions were 54 % (v/v) ethanol concentration, 60 °C, 31 min, and a 15 (mL/g) solvent-to-solid ratio resulting in a yield of 24.72 g/g (%), TPC of 489.54 mg gallic acid/g, TFC of 149.81 mg quercetin/g, and IC50 of 18.21 µg/mL. UAE outperformed Soxhlet extraction in yield, bioactive compound composition, and antioxidant capacity. Strong correlations were found between TPC, TFC, and antioxidant capacity, with TFC having a more significant impact. I. viscosa extract was found to be a potent antioxidant and delay the oxidation of SFO during accelerated storage due to peroxide value and oxidative induction time analysis. Microstructural analysis illuminated the structural changes induced by the extraction methods. In conclusion, this study not only optimized UAE of I.viscosa, showing superior efficiency and antioxidant capacity, but also demonstrated the practical application of I.viscosa in enhancing sunflower oil shelf life, thereby providing valuable insights for the field of food engineering and antioxidant research.

Phytochemical characterization and biological activities of Inula viscosa L. Aiton: a promising plant from Turkey.

The methanol extract of Inula viscosa (IVM) was investigated for its antioxidant potential using the DPPH and ABTS radical scavenging as well as iron chelating assays (ICA). The total phenol (TPC) and flavonoid contents (TFC) of IVM were determined using the Folin-Ciocalteu and aluminum trichloride methods, respectively. Antimicrobial activity of different concentrations of I. viscosa methanol extract was investigated by disc diffusion and broth microdilution method. The IVM extract was found to be containing TPC (236.78 ± 7.63 mg GAE/g) and TFC (94.36 ± 1.86 mg QE/g). Antioxidant activity IC50 values for the DPPH, ABTS and ICA assays were found to be 277.7 ± 3.68, 2.44 ± 0.02, and 222.1 ± 0.71 µg/mL, respectively. The MIC values of the IVM on the tested microorganisms ranged from 0.48 to 7.81 mg/mL. Furthermore, IVM extract was demonstrated 18.32 ± 1.37%, 23.06 ± 1.05%, 4.72 ± 0.13%, 15.13 ± 0.37% and 37.64 ± 4.02% inhibition against tyrosinase, α-amylase, α-glucosidase, AChE and BChE, respectively. In the results of LC-MS/MS analysis, acacetin, quercetin, chlorogenic acid and protocatechuic acid were determined as most dominant compounds. These findings suggested that this plant may be a natural resource for creating novel medicinal compounds.

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.

Apoptotic and antiproliferative effects of Inula viscosa L. water extract in the expression of microRnas on HCT 116 cell line: an in vitro study.

In this study, the antiproliferative and apoptotic effects of Inula viscosa L. water extract (IVE) on HCT 116 has been examined, and the change in the expression of miRNAs. Phenolic compounds of IVE were determined as µg/g extract using by HPLC-DAD. Quantitative determination of apoptosis, cell viability, IC50 values and miRNAs of the cells were determined during 24, and 48 hours. IVE contain coumarin, rosmarinic acid and chlorogenic acid. According to the findings of our study, the expression of miR-21 and miR-135a1 was upregulated, and miR-145 was downregulated in HCT 116 cells (Control). Additionally, IVE was found to have significant potential in regulating miRNAs, downregulating miR-21, miR-31 and miR-135a1, and upregulating miR-145 in HCT-116 cells. All these results show that the anticancer effect of IVE via regulating miRNAs' expression has been demonstrated for the first time, and may be candidate biomarkers in colorectal cancer.

Biofilm Inhibition of Inula viscosa (L.) Aiton and Globularia alypum L. Extracts Against Candida Infectious Pathogens and In Vivo Action on Galleria mellonella Model.

The increasing importance of fungal infections has fueled the search for new beneficial alternatives substance from plant extracts. The current study investigates the antifungal and antibiofilm activity of Inula viscosa (L.) Aiton and Globularia alypum (L.) leaves extracts against Candida both in vitro and in vivo. The inhibition of planktonic and sessile Candida albicans and Candida glabrata growth using both leaf extracts are evaluated. Moreover; an in vivo infection model using Galleria mellonella larvae; infected and treated with the extracts are performed. All extracts show fungicidal activity; with a minimum fungicidal concentration (MFC) ranging from 128 to 512 µg mL-1 against the two selected strains of Candida. In particular, the best results are obtained with methanolic extract of I. viscosa and G. alypum with an MFC value of 128 µg mL-1 . The extracts are capable to prevent 90% of biofilm development at minor concentrations ranging from 100.71 ± 2.49 µg mL-1 to 380.4 ± 0.92 µg mL-1 . In vivo, tests on Galleria mellonella larvae show that the extracts increase the survival of the larvae infected with Candida. The attained results reveal that I. viscosa and G. alypum extracts may be considered as new antifungal agents and biofilm inhibiting agents for the pharmaceutical and agro-food field.

Phytochemical Extracts of Dittrichia viscosa (L.) Greuter from Agroecological Systems: Seed Antigerminative Properties and Effectiveness in Counteracting Alternaria Leaf Spot Disease on Baby-Leaf Spinach.

Dittrichia viscosa (L.) Greuter subsp. viscosa (Asteraceae) is a perennial species naturally distributed in arid and marginal areas whose agroecological cultivation could be a useful innovation to produce quality biomass to extract phenolic-rich phytochemical blends. Here, biomass-yield trends were profiled at different growth stages under direct cropping, and inflorescences, leaves, and stems were submitted to water extraction and hydrodistillation. Then, four extracts were investigated for their biological activities in invitro and in planta assays. Extracts inhibited cress (Lepidium sativum)- and radish (Raphanus sativus)-seed germination and root elongation. All samples showed dose-dependent antifungal activity in the plate experiments, inhibiting up to 65% of the growth of the fungal pathogen Alternaria alternata, a leaf-spot disease agent of baby spinach (Spinacea oleracea). However, only the extracts from dried green parts and fresh inflorescences at the highest concentration significantly reduced (54%) the extent of Alternaria necrosis on baby spinach. UHPLC-HRMS/MS analysis revealed that the main specialized metabolites of the extracts are caffeoyl quinic acids, methoxylated flavonoids, sesquiterpene compounds such as tomentosin, and dicarboxylic acids, which may explain the observed bioactivity. Plant extracts obtained through sustainable methodology can be effective in biological agricultural applications.

Inula viscosa ameliorates acetic acid induced ulcerative colitis in rats.

Increased pro-inflammatory cytokines and oxidative stress contribute to the pathophysiology of ulcerative colitis (UC). Inula viscosa is a plant with antioxidant and anti-inflammatory properties. We investigated the effect of an ethanolic extract of I. viscosa on an experimental UC model created using acetic acid. Rats were divided into four groups of eight: group 1, control; group 2, 3% acetic acid group; group 3, 100 mg/kg sulfasalazine + 3% acetic acid group; group 4, 400 mg/kg I. viscosa + 3% acetic acid. I. viscosa and sulfasalazine were administered by oral gavage and 3% acetic acid was administered per rectum. We found that I. viscosa treatment decreased colon malondialdehyde, tumor necrosis factor-α, interleukin-1 beta and nuclear factor kappa B levels; it increased reduced glutathione, nuclear factor erythroid 2-related factor 2, heme oxygenase-1 and kelch-like ECH-associated protein 1 levels and glutathione peroxidase enzyme activity. Group 1 colon exhibited normal histological structure. Slight inflammatory cell infiltration and edema and insignificant slight erosion in crypts were detected in colon tissues of group 4. We found that I. viscosa reduced oxidative stress and inflammation, which was protective against UC by inducing the Nrf-2/Keap-1/HO-1 pathway in the colon.

Biosorption of zinc (II) from synthetic wastewater by using Inula Viscosa leaves as a low-cost biosorbent: Experimental and molecular modeling studies.

The use of biosorption as a strategy for lowering the amount of pollution caused by heavy metals is particularly encouraging. In this investigation, a low-cost and efficient biosorbent, Inula Viscosa leaves were used to remove zinc ions (Zn2+) from synthetic wastewater. A Fourier transform infrared spectroscopy experiment, a scanning electron microscopy experiment, and an energy dispersive X-ray spectroscopy experiment were used to describe the support. Several different physicochemical factors, such as the beginning pH value, contact duration, initial zinc concentration, biosorbent dose, and temperature, were investigated in this study. When the Langmuir, Freundlich, Temkin, Toth, and Redlich-Peterson models were used to match the data from the Inula Viscosa leaves biosorption isotherms, it was found that the biosorption isotherms correspond most closely with the Langmuir isotherm. On the other hand, the kinetic biosorption process was investigated using pseudo-first-order, pseudo-second-order (PS2), and Elovich models. The PS2 model was the one that provided the most accurate description of the biosorption kinetics. The thermodynamics process shows the spontaneous and endothermic character of Zn2+ sorption on Inula Viscosa leaves, which also entails the participation of physical interactions. In addition, the atom-in-molecule analysis, density functional theory, and the conductor like screening model for real solvents, were used to investigate the relationship that exists between quantum calculations and experimental outcomes.

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.

Investigation on the influence of ultrasonic pretreatment on color, quality and antioxidant attributes of microwave dried Inula viscosa (L.).

Impact of various ultrasound pretreatment and microwave drying parameters on the qualitative and antioxidant characteristics of Inula viscosa (L.) was investigated in this study. The leaves of Inula viscosa (L.) were sonicated for 10, 20, and 30 min in an ultrasonic bath (37 kHz, 150 Watts). Microwave drying was done at three distinct times (1, 3, and 5 min) and with three different microwave power levels (100, 180, and 300 Watts). Microwave dried samples were tested for color characteristics (L*, a*, b*), chlorophyll, carotenoid, total phenol, and antioxidant content. All dried samples were prepared by infusing them in hot water as tea, and the sensorial properties of teas including odor, color, aroma, and overall acceptability were evaluated by panelists. For 10, 20, and 30 min of ultrasound pretreatment, the L* values of leaves varied from 37.70 to 49.76, 34.97 to 46.25, and 27.88 to 43.34, respectively. The total carotenoid concentration ranged from 0.12 to 0.32 mg/g DW, while the total chlorophyll content was from 0.44 to 0.94 mg/g DW. The antioxidant activity of Inula viscosa (L.) leaves that were dried at 300 Watts for 5 min did not change significantly as a result of ultrasound pretreatment. There was a significant positive correlation between aroma and TPC, as well as between color and overall acceptability. The darkest-colored teas were deemed preferable by the panelists.

A new specific method for isolation of tomentosin with a high yield from Inula viscosa (L.) and determination of its bioactivities.

INTRODUCTION: Tomentosin, the characteristic component of Inula viscosa (L.) is an important sesquiterpene lactone with anticarcinogenic effects. Methods of obtaining pure tomentosin are not sufficient for anticancer drug research. OBJECTIVES: This study aims to develop a specific method to isolate tomentosin from I. viscosa with high yield. It also aims to investigate the inhibitory effects of tomentosin on human carbonic anhydrase I (hCAI), human carbonic anhydrase II (hCAII), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), α-glucosidase, and α-amylase enzymes. MATERIAL AND METHODS: Tomentosin was purified by a specific column chromatography method. The content of tomentosin in dichloromethane, dichloromethane by Soxhlet method, ethanol and ethanol by Soxhlet method extracts of I. viscosa was determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Half maximal inhibitory concentration (IC50 ) and inhibition constant (Ki ) values were calculated to determine in vitro enzyme inhibition effects. RESULTS: Tomentosin was isolated in high yield (0.64%). The IC50 and Ki values for tomentosin were calculated as 5.00 ± 0.19 (r = 0.9688) and 4.62 ± 0.10 µM for hCAI, 5.40 ± 0.26 (r = 0.9677) and 5.22 ± 0.31 µM for hCAII, 6.75 ± 0.208 (r = 0.9891) and 3.75 ± 0.27 µM for AChE, 6.67 ± 0.307 (r = 0.9820) and 0.51 ± 0.11 µM for BChE, 26.61 ± 0.236 (r = 0.9815) and 2.61 ± 0.71 µM for α-glucosidase and 26.89 ± 1.54 µM (r = 0.9670) for α-amylase, respectively. CONCLUSION: Tomentosin was isolated in high yield from the paste-like extract of I. viscosa compared to the positive controls, it was determined that tomentosin was weakly effective against hCAI, hCAII, AChE and BChE, but thoroughly effective against α-glucosidase and α-amylase. These results suggested that tomentosin has α-glucosidase and α-amylase inhibitor potential.

Inula viscosa phenolic extract suppresses colon cancer cell proliferation and ulcerative colitis by modulating oxidative stress biomarkers.

Inula viscosa is a perennial herbaceous plant native to the Mediterranean Basin, which is used topically for the treatment of various diseases in folk medicine. This study aimed to evaluate the in vivo intestinal anti-inflammatory activity of the ethanolic extract of I. viscosa (EEIV) and to test its effect on a colorectal cancer cell line. EEIV was administered to rats orally and daily at 100 and 200 mg/kg body weight for 7 days, and then colitis was induced by intrarectal instillation of 2 ml of 4% (v/v) acetic acid (AA) solution. At the end of the experiment, clinical examinations of the rats were conducted by evaluating macroscopic and histological signs of colonic tissues and measuring erythrocyte sedimentation rate (ESR) and the levels of C-reactive protein, fibrinogen, myeloperoxidase (MPO), malondialdehyde (MDA) and nitric oxide (NO). Using MTS assay, the antiproliferative effect of EEIV against human colon carcinoma HT29 cells and cytotoxicity on nondifferentiated Caco-2 cell line was evaluated. EEIV significantly decreased the ESR and fibrinogen levels as compared to control colitic rats (P < 0.001). It also significantly decreased the NO, MDA, and MPO levels in the colon tissue compared with the untreated colitic group (P < 0.001). These results were confirmed by macroscopic and histological examination, which showed significant protection against AA-induced ulcerative colitis. Furthermore, EEIV at a concentration of 369.88 µg/ml did not show cytotoxicity on confluent Caco-2 cells, with significant inhibition of colorectal cancer cell (HT29) growth (EC50 = 62.39 µg/ml). These results demonstrate that EEIV plays a potential role as a pharmacological tool in the management of inflammatory bowel disease and prevention of colorectal cancer.

Isolation, identification, and activity evaluation of antioxidant components from Inula viscosa: A bioguided approach.

Oxidative stress is linked to several invasive diseases which causes significant clinical and economic impact, therefore, there is a need to develop new antioxidants. The natural products could play an important role in overcoming the current need. In the present work, the antioxidant bioassay-guided fractionation of the ethanolic extract of Inula viscosa leaves (Asteraceae) was performed using DPPH and ABTS assays affording three known compounds, which were successfully characterized as ilicic acid (1), taxifolin (2) and quercetin (3) based on 1D, 2D NMR. Compounds 2 and 3 were identified as the most active, displaying similar or higher potency against ABTS (value 41.27 for quercetin and 142.58 for taxifolin) and similar activity against DPPH (value 41.27 for quercetin and 142.58 for taxifolin) than the well-known reference, ascorbic acid (value 65.36 for quercetin and 58.43 for taxifolin) but less potency than the standard gallic acid. The discussion of SAR of the antioxidant potential revealed that the type of natural product is crucial for the activity and the substitution pattern on the flavonoid skeleton modulate the antioxidant profile. Our findings show that I. viscosa leaves may be a natural source of antioxidants and once again the role of flavonoids health benefits is more strongly endorsed.

Antimicrobial Effects of Inula viscosa Extract on the In Situ Initial Oral Biofilm.

Given the undesirable side effects of commercially used mouth rinses that include chemically synthesized antimicrobial compounds such as chlorhexidine, it is essential to discover novel antimicrobial substances based on plant extracts. The aim of this study was to examine the antimicrobial effect of Inula viscosa extract on the initial microbial adhesion in the oral cavity. Individual test splints were manufactured for the participants, on which disinfected bovine enamel samples were attached. After the initial microbial adhesion, the biofilm-covered oral samples were removed and treated with different concentrations (10, 20, and 30 mg/mL) of an I. viscosa extract for 10 min. Positive and negative controls were also sampled. Regarding the microbiological parameters, the colony-forming units (CFU) and vitality testing (live/dead staining) were examined in combination with fluorescence microscopy. An I. viscosa extract with a concentration of 30 mg/mL killed the bacteria of the initial adhesion at a rate of 99.99% (log10 CFU value of 1.837 ± 1.54). Compared to the negative control, no killing effects were determined after treatment with I. viscosa extract at concentrations of 10 mg/mL (log10 CFU value 3.776 ± 0.831; median 3.776) and 20 mg/mL (log10 CFU value 3.725 ± 0.300; median 3.711). The live/dead staining revealed a significant reduction (p < 0.0001) of vital adherent bacteria after treatment with 10 mg/mL of I. viscosa extract. After treatment with an I. viscosa extract with a concentration of 30 mg/mL, no vital bacteria could be detected. For the first time, significant antimicrobial effects on the initial microbial adhesion in in situ oral biofilms were reported for an I. viscosa extract.

Phytochemical Profile, Antioxidant Capacity, α-Amylase and α-Glucosidase Inhibitory Potential of Wild Moroccan Inula viscosa (L.) Aiton Leaves.

Medicinal plants offer imperative sources of innovative chemical substances with important potential therapeutic effects. Among them, the members of the genus Inula have been widely used in traditional medicine for the treatment of several diseases. The present study investigated the antioxidant (DPPH, ABTS and FRAP assays) and the in vitro anti-hyperglycemic potential of aerial parts of Inula viscosa (L.) Aiton (I. viscosa) extracts through the inhibition of digestive enzymes (α-amylase and α-glucosidase), responsible of the digestion of poly and oligosaccharides. The polyphenolic profile of the Inula viscosa (L.) Aiton EtOAc extract was also investigated using HPLC-DAD/ESI-MS analysis, whereas the volatile composition was elucidated by GC-MS. The chemical analysis resulted in the detection of twenty-one polyphenolic compounds, whereas the volatile profile highlighted the occurrence of forty-eight different compounds. Inula viscosa (L.) Aiton presented values as high as 87.2 ± 0.50 mg GAE/g and 78.6 ± 0.55mg CE/g, for gallic acid and catechin, respectively. The EtOAc extract exhibited the higher antioxidant activity compared to methanol and chloroform extracts in different tests with (IC50 = 0.6 ± 0.03 µg/mL; IC50 = 8.6 ± 0.08 µg/mL; 634.8 mg ± 1.45 AAE/g extract) in DPPH, ABTS and FRAP tests. Moreover, Inula viscosa (L.) Aiton leaves did show an important inhibitory effect against α-amylase and α-glucosidase. On the basis of the results achieved, such a species represents a promising traditional medicine, thanks to its remarkable content of functional bioactive compounds, thus opening new prospects for research and innovative phytopharmaceuticals developments.

Tomentosin inhibits cell proliferation and induces apoptosis in MOLT-4 leukemia cancer cells through the inhibition of mTOR/PI3K/Akt signaling pathway.

Leukemia is amongst the cancers accountable for substantial mortality around the world. Tomentosin is a bioactive compound with a pharmacological significance, and its anticancer property against human leukemia MOLT-4 cell line has never been reported. Hence, the objective of this study was to explore the anticancer activity of tomentosin in MOLT-4 human leukemia cells. In the current investigation, the cytotoxic effects of tomentosin ensuing potent toxicity (IC50 : 10 µM) in MOLT-4 cells after incubation at 24 h have been presented. Furthermore, tomentosin triggered intracellular reactive oxygen species production and showed the induction of intrinsic/mitochondrial pathways in treated MOLT-4 cells, revealing a significant cytotoxicity activity. Also, fluorescent microscopic studies using acridine orange/ethidium bromide and propidium iodide staining confirmed the occurrence of apoptosis in tomentosin-treated MOLT-4 cells. Quantitative reverse transcription polymerase chain reaction presented a negative regulation of cyclin D1 and BcL-2 expression and a positive regulated BAX and caspase-3 messenger RNA expression in tomentosin-treated MOLT-4 cells. Tomentosin further inhibited the inflammatory transcription factors such as nuclear factor κB (NF-κB), tumor necrosis factor α, interleukin 1ß (IL-1ß), and IL-6. Additionally, inhibition of the m-TOR/PI3K/AKT protein expression by tomentosin in MOLT-4 cells was confirmed. Overall, these findings lead to a conclusion that tomentosin induces apoptosis in MOLT-4 cells through caspase-facilitated proapoptotic pathway, and inhibition of the NF-κB-stimulated Bcl-2 facilitated the antiapoptotic pathway.

Exploring the Anti-Infective Value of Inuloxin A Isolated from Inula viscosa against the Brain-Eating Amoeba (Naegleria fowleri) by Activation of Programmed Cell Death.

Primary amoebic meningoencephalitis (PAM), caused by the pathogenic free-living amoeba Naegleria fowleri, is a rare but fatal disease. Nowadays, no fully effective therapy is available to erradicate or prevent this disease. Natural products could constitute a promising source of useful bioactive compounds in drug discovery. The present study is a characterization of main active compounds from the ethanolic extract of Inula viscosa (Asteraceae) leaves against N. fowleri trophozoites. Four compounds (1-4) were successfully identified by spectroscopic techniques, but only inuloxin A displayed a potential antiamoebic activity with an IC50 of 21.27 µM. The specificity of this compound toward the studied strain leads us to analyze the insight into its mechanism of action by performing in vitro assays of programmed cell death markers and to discuss the structure-activity relationship (SAR). The obtained results demonstrated that inuloxin A interferes with various processes leading to membrane damage, mitochondria alteration, chromatin condensation, and ROS accumulation, which highlight features specific to apoptosis. The current findings could be a promising step for developing new effective drugs against PAM.

Sesquiterpenoids and flavonoids from Inula viscosa induce programmed cell death in kinetoplastids.

Neglected tropical diseases such as leishmaniasis and American trypanosomiasis represent an increasing health problem. Current treatments are not satisfactory which remains an urgent need for novel, cheap and safe chemotherapies. In the course of our ongoing search for new potential anti-protozoal agents, this study aimed to perform a bio-guided fractionation of Inula viscosa (Asteraceae) using in vitro assays against three strains of Leishmania and Trypanosma genus. Eight known compounds were identified from the ethanolic extract of leaves, sesquiterpenoids (3 and 4) and flavonoids (5 and 6) were characterized as the main bioactive constituents. Sesquiterpene lactones 3 and 4 (IC50 values between 4.99 and 14.26 µM) showed promising antiparasitic activity against promastigotes of L. donovani, L. amazonensis and epimastigotes of T. cruzi. Their structures were successfully characterized by spectroscopic techniques including 1D and 2D NMR experiments. Furthermore, the main bioactive compounds 4, 5 and 6 displayed higher potency (IC50 values between 0.64 and 2.13 µM) against amastigotes of L. amazonensis than miltefosine (IC50 3.11 µM), and a low toxicity on macrophages cell line (SI > 45). The analysis of structure-activity relationship (SAR) of the anti-protozoal activity revealed that lactonization or oxidation enhanced the biological profile, suggesting that the hydrophobic moiety was presumably involved in the activity by increasing the affinity and/or cell membrane permeability. In order to get an insight into the mechanism of action of these compounds, programmed cell death (PCD) experiments were performed, and the obtained results suggest that the reported compounds induced PCD in the treated parasites. These results highlight that sesquiterpenoids and flavonoids from I. viscosa could constitute an interesting scaffold for the development of novel antikinetoplastid agents.

Antiproliferative and proapoptotic effects of Inula viscosa extract on Burkitt lymphoma cell line.

Burkitt lymphoma is a very aggressive B-cell non-Hodgkin lymphoma. Although remarkable progress has been made in the therapeutic scenario for patients with Burkitt lymphoma, search and development of new effective anticancer agents to improve patient outcome and minimize toxicity has become an urgent issue. In this study, the antitumoral activity of Inula viscosa, a traditional herb obtained from plants collected on the Asinara Island, Italy, was evaluated in order to explore potential antineoplastic effects of its metabolites on Burkitt lymphoma. Raji human cell line was treated with increasing Inula viscosa extract concentration for cytotoxicity screening and subsequent establishment of cell cycle arrest and apoptosis. Moreover, gene expression profiles were performed to identify molecular mechanisms involved in the anticancer activities of this medical plant. The Inula viscosa extract exhibited powerful antiproliferative and cytotoxic activities on Raji cell line, showing a dose- and time-dependent decrease in cell viability, obtained by cell cycle arrest in the G2/M phase and an increase in cell apoptosis. The treatment with Inula viscosa caused downregulation of genes involved in cell cycle and proliferation (c-MYC, CCND1) and inhibition of cell apoptosis (BCL2, BCL2L1, BCL11A). The Inula viscosa extract causes strong anticancer effects on Burkitt lymphoma cell line. The molecular mechanisms underlying such antineoplastic activity are based on targeting and downregulation of genes involved in cell cycle and apoptosis. Our data suggest that Inula viscosa natural metabolites should be further exploited as potential antineoplastic agents against Burkitt lymphoma.