Eucalyptus globulus Labill. decoction extract inhibits the growth of NCI-H460 cells by increasing the p53 levels and altering the cell cycle profile

Chemosensitizing effect of pentoxifylline in sensitive and multidrug-resistant non-small cell lung cancer cells

Aim: Multidrug resistance (MDR) is frequent in non-small cell lung cancer (NSCLC) patients, which can be due to its fibrotic stroma. This work explores the combination of pentoxifylline, an anti-fibrotic and chitinase 3-like-1 (CHI3L1) inhibitor drug, with conventional chemotherapy to improve NSCLC treatment. Methods: The effect of pentoxifylline in the expression levels of P-glycoprotein (P-gp), CHI3L1 and its main downstream proteins, as well as on cell death, cell cycle profile, and P-gp activity was studied in two pairs of sensitive and MDR counterpart NSCLC cell lines (NCI-H460/NCI-H460/R and A549/A549-CDR2). Association studies between CHI3L1 gene expression and NSCLC patients' survival were performed using The Cancer Genome Atlas (TCGA) analysis. The sensitizing effect of pentoxifylline to different drug regimens was evaluated in both sensitive and MDR NSCLC cell lines. The cytotoxicity of the drug combinations was assessed in MCF10A non-tumorigenic cells. Results: Pentoxifylline slightly decreased the expression levels of CHI3L1, β-catenin and signal transducer and activator of transcription 3 (STAT3), and caused a significant increase in the G1 phase of the cell cycle in both pairs of NSCLC cell lines. A significant increase in the % of cell death was observed in the sensitive NCI-H460 cell line. TCGA analysis revealed that high levels of CHI3L1 are associated with low overall survival (OS) in NSCLC patients treated with vinorelbine. Moreover, pentoxifylline sensitized both pairs of sensitive and MDR NSCLC cell lines to the different drug regimens, without causing significant toxicity to non-tumorigenic cells. Conclusion: This study suggests the possibility of combining pentoxifylline with chemotherapy to increase NSCLC therapeutic response, even in cases of MDR.

E. globulus leaf EO exhibits anti-inflammatory effects by regulating GSDMD-mediated pyroptosis, thereby alleviating neurological impairment and neuroinflammation in experimental stroke mice

ETHNOPHARMACOLOGICAL RELEVANCE

Aromatic and medicinal plants continue to be a major component of alternative and traditional medicine in the developing countries. Eucalyptus globulus (Labill.) is being employed to cultivation and production in China. However, few studies have reported the chemical composition and anti-inflammatory activity of Eucalyptus globulus (Labill.) leaf essential oil (E. globulus leaf EO) extracted from Eucalyptus globulus.

AIM OF THE STUDY

This study aimed to assess the composition of E. globulus leaf EO and identify its bacteriostatic action as well as anti-inflammatory activity. Importantly, we evaluated the effect of E. globulus leaf EO on neurological impairment and neuroinflammation in experimental stroke mice.

MATERIALS AND METHODS

Gas Chromatography-Mass Spectrometer (GC-MS) analyses was employed to evaluate the chemical components of E. globulus leaf EO, and the relative content of each component was determined by area normalization method. The antimicrobial activity of E. globulus leaf EO was determined by Oxford cup method and microbroth dilution assay. Cytotoxic activity of E. globulus leaf EO on THP-1 cells or BV2 cells in vitro was determined by CCK8 assay. In addition, the lipopolysaccharide (LPS)/ATP-induced inflammation model in THP-1 cells or BV2 cells were established, and the relative expression of TNF-α, IL-1β, MCP-1and IL-6 were confirmed by RT-PCR. Furthermore, the expression of protein GSDMD, IL-lβ, NLRP3 and NFκB signaling pathway were assessed by immunoblotting. In vivo,the experimental stroke model constructed by middle cerebral artery occlusion/reperfusion (MCAO/R) in mice was employed and subsequently treated with E. globulus leaf EO (50,100 mg/kg, subcutaneous injection) for 3 days to assess neurological impairment and neuroinflammation. Behavioral and neuronal damage were assessed using grip strength test, rod trarod test, and Nissl staining. Pro-inflammatory factors in serum or ischemic brain tissue was detected by ELISA kits.

RESULTS

GC-MS analyses revealed that the major compound in E. globulus leaf EO was eudesmol (71.967%). E. globulus leaf EO has antimicrobial activity against Staphylococcus aureus (gram positive bacteria, MIC = 0.0625 mg/mL), Escherichia coli (gram negative bacteria, MIC = 1 mg/mL), and Candida albicans (MIC = 4 mg/mL). E. globulus leaf EO (0.5312, 1.0625, and 2.15 mg/mL) significantly decreased the expression of inflammation-related genes, including IL-1β, TNF-α, MCP-1, and IL-6. Furthermore, reduced levels of TLR4, Myd88, phosphorylated NF-κB P65, and IκBα were found in the E. globulus leaf EO group for BV2 cells (1.025, and 2.125 mg/mL). In addition, the expression levels of GSDMD, NLRP3, IL-1β and AIM2 were significantly decreased in the E. globulus leaf EO group when compared with the LPS -stimulated group, regulating GSDMD-mediated pyroptosis. In vivo, E. globulus leaf EO improved neurological functional deficits, inhibited excessive activation of microglia, and reduced the secretion of pro-inflammatory factors IL-1β, TNF-α in the ischemic tissue and serum after MCAO/R.

CONCLUSION

E. globulus leaf EO has strong antibacterial and anti-inflammatory activity, which has been implicated in blocking GSDMD-mediated pyroptosis. Moreover, E. globulus leaf EO could exert neuroprotective effect on cerebral ischemia-reperfusion injury.

Plant extracts as biocontrol agents against Aspergillus carbonarius growth and ochratoxin A production in grapes

Aspergillus carbonarius (Bainier) Thom. is an important pathogen and ochratoxin A (OTA) producer in grapes that can be controlled by adopting sustainable approaches. Here we evaluate the application of natural plant extracts as an alternative to synthetic fungicides to reduce OTA contamination and to prevent infection of grapes by two isolates of A. carbonarius. In a preliminary screening, natural extracts of chestnut flower, cistus, eucalyptus, fennel, and orange peel were evaluated for their antifungal and anti-mycotoxigenic efficiency in a grape-based medium at concentrations of 10 and 20 mg/mL. Cistus and orange peel extracts demonstrated the best antifungal activity at both concentrations. Although the eucalyptus extract demonstrated no significant effect on Aspergillus vegetative growth, it significantly reduced OTA by up to 85.75 % at 10 mg/mL compared to the control. Chestnut flower, cistus, eucalyptus, and orange peel extracts were then tested at the lowest concentration (10 mg/mL) for their antifungal activity in artificially inoculated grape berries. The cistus and orange peel extracts demonstrated the greatest antifungal activity and significantly reduced mold symptoms in grapes. Moreover, all tested natural extracts were able to reduce OTA content in grape berries (17.7 ± 8.3 % - 82.3 ± 3.85 % inhibition), although not always significantly. Eucalyptus extract was particularly efficient, inhibiting OTA production by both strains of A. carbonarius by up to >80 % with no effects on fungal growth. The use of natural eucalyptus extract represents a feasible strategy to reduce OTA formation without disrupting fungal growth, apparently maintaining the natural microbial balance, while cistus and orange peel extracts appear promising as inhibitors of A. carbonarius mycelial growth. Our findings suggest that plant extracts may be useful sources of bioactive chemicals for preventing A. carbonarius contamination and OTA production. Nonetheless, it will be necessary to evaluate their effect on the organoleptic properties of the grapes.

Novel family of [RuCp(N,N)(P)]+ compounds with simultaneous anticancer and antibacterial activity: Biological evaluation and solution chemistry studies

A family of ten novel ruthenium(II)-cyclopentadienyl organometallics of general formula [Ru(η5-C5H5)(N,N)(PPh2(C6H4COOR)][CF3SO3] (1-10) in which (N,N) = 4,4'-R'-2,2'-bipyridyl (R = -H or -CH2CH2OH; R' = -H, -CH3, -OCH3, -CH2OH, and -CH2-biotin) was prepared from [Ru(η5-C5H5)(PPh2(C6H4COOH))2Cl]. All compounds were fully characterized by means of several spectroscopic and analytical techniques, and the molecular structures of [Ru(η5-C5H5)(PPh2(C6H4COOH))2Cl], 1, 3 and 4 have been additionally studied by single-crystal X-ray diffraction. The anticancer activity of all compounds was evaluated in sensitive and multidrug-resistant counterpart cell lines from human colorectal cancer (Colo 205 and Colo 320) and non-small cell lung cancer NSCLC (A549, NCI-H460 versus NCI-H460/R) as well. Notably, compounds 6 and 7 (R CH2CH2OH and (N,N) = bipy or Me2bipy, respectively) showed antiproliferative effect against both cell lines with high intrinsic selectivity towards cancer cells. The antibacterial activity of all compounds was also evaluated against both Gram negative and Gram positive strains, and some compounds in the series showed potent antibacterial activity against Staphylococcus aureus strains, including the methicillin-resistant MRSA strains. Solution speciation studies revealed that the complexes bearing the PPh2(C6H4COO-) ligand are neutral at physiological pH (7.4) in contrast with their ethylene glycol derivatives that have a permanent positive charge. While all compounds are lipophilic, the difference in the distribution coefficient for neutral and charged complexes is around one order of magnitude. Complexes 6 and 7 exhibited excellent biological activity and were selected for further studies. Spectrofluorometric methods were used to investigate their interaction with biomolecules such as human serum albumin (HSA) and calf thymus DNA (ct-DNA). For these complexes, binding site II of HSA is a possible binding pocket through non-covalent interactions. The release of ethidium from the DNA adduct by the charged complexes proves their interaction with DNA in contrast to the neutral ones. In conclusion, Ru(II)-cyclopentadienyl complexes with 2,2'-bipyridyl-derivatives and an ethylene glycol moiety tethered to the phenylphosphane co-ligand are very promising from a therapeutic perspective, in particular complexes 6 and 7 that display remarkable antibacterial activity with a high anti-proliferative effect against colon and non-small cell lung cancers, both clinically challenging neoplasias in need of effective solutions.

Therapeutic Strategies for Pancreatic-Cancer-Related Type 2 Diabetes Centered around Natural Products

Pancreatic ductal adenocarcinoma (PDAC), a highly malignant neoplasm, is classified as one of the most severe and devastating types of cancer. PDAC is a notable malignancy that exhibits a discouraging prognosis and a rising occurrence. The interplay between diabetes and pancreatic cancer exhibits a reciprocal causation. The identified metabolic disorder has been observed to possess noteworthy consequences on health outcomes, resulting in elevated rates of morbidity. The principal mechanisms involve the suppression of the immune system, the activation of pancreatic stellate cells (PSCs), and the onset of systemic metabolic disease caused by dysfunction of the islets. From this point forward, it is important to recognize that pancreatic-cancer-related diabetes (PCRD) has the ability to increase the likelihood of developing pancreatic cancer. This highlights the complex relationship that exists between these two physiological states. Therefore, we investigated into the complex domain of PSCs, elucidating their intricate signaling pathways and the profound influence of chemokines on their behavior and final outcome. In order to surmount the obstacle of drug resistance and eliminate PDAC, researchers have undertaken extensive efforts to explore and cultivate novel natural compounds of the next generation. Additional investigation is necessary in order to comprehensively comprehend the effect of PCRD-mediated apoptosis on the progression and onset of PDAC through the utilization of natural compounds. This study aims to examine the potential anticancer properties of natural compounds in individuals with diabetes who are undergoing chemotherapy, targeted therapy, or immunotherapy. It is anticipated that these compounds will exhibit increased potency and possess enhanced pharmacological benefits. According to our research findings, it is indicated that naturally derived chemical compounds hold potential in the development of PDAC therapies that are both safe and efficacious.

In Vitro and In Silico Activities of E. radiata and E. cinerea as an Enhancer of Antibacterial, Antioxidant, and Anti-Inflammatory Agents

Eucalyptus, a therapeutic plant mentioned in the ancient Algerian pharmacopeia, specifically two species belonging to the Myrtaceae family, E. radiata and E. cinerea, were investigated in this study for their antibacterial, antioxidant, and anti-inflammatory properties. The study used aqueous extracts (AE) obtained from these plants, and the extraction yields were found to be different. The in vitro antibacterial activity was evaluated using a disc diffusion assay against three typical bacterial strains. The results showed that the two extracts were effective against all three strains. Both extracts displayed significant antioxidant activity compared to BHT. The anti-inflammatory impact was evaluated using a protein (BSA) inhibition denaturation test. The E. radiata extract was found to inhibit inflammation by 85% at a concentration of 250 µg/mL, significantly higher than the Aspirin. All phytoconstituents present good pharmacokinetic characteristics without toxicity except very slight toxicity of terpineol and cineol and a maximum binding energy of -7.53 kcal/mol for its anti-TyrRS activity in silico. The study suggests that the extracts and their primary phytochemicals could enhance the efficacy of antibiotics, antioxidants, and non-steroidal anti-inflammatory drugs (NSAIDs). As pharmaceutical engineering experts, we believe this research contributes to developing natural-based drugs with potential therapeutic benefits.

Phenolic metabolites as therapeutic in inflammation and neoplasms: molecular pathways explaining their efficacy

Polyphenols, also known as phenolic compounds, are chemical substances containing aromatic rings as well as at least two hydroxyl groups. Natural phenolic compounds exist widely in plants, which protect plants from ultraviolet radiation and other insults. Phenolic compounds have superior pharmacological and nutritional properties (antimicrobial, antibacterial, antiviral, anti-sclerosis, antioxidant, and anti-inflammatory activities), which have been paid more and more attention by the scientific community. Phenols can protect key cellular components from reactive free radical damage, which is mainly due to their property to activate antioxidant enzymes and alleviate oxidative stress and inflammation. It can also inhibit or isolate reactive oxygen species and transfer electrons to free radicals, thereby avoiding cell damage. It has a regulatory role in glucose metabolism, which has a promising prospect in the prevention and intervention of diabetes. It also prevents cardiovascular disease by regulating blood pressure and blood lipids. Polyphenols can inhibit cell proliferation by affecting Erk1/2, CDK, and PI3K/Akt signaling pathways. Polyphenols can function as enhancers of intrinsic defense systems, including superoxide dismutase (SOD) and glutathione peroxidase (GPX). Simultaneously, they can modulate multiple proteins and transcription factors, making them promising candidates in the investigation of anti-cancer medications. This review focuses on multiple aspects of phenolic substances, including their natural origins, production process, disinfection activity, oxidative and anti-inflammatory functions, and the effects of different phenolic substances on tumors.

Antiproliferative Activities of the Lipophilic Fraction of Eucalyptus camaldulensis against MCF-7 Breast Cancer Cells, UPLC-ESI-QTOF-MS Metabolite Profile, and Antioxidative Functions

Although a number of pharmacological properties have been linked to Eucalyptus camaldulensis leaf essential oil and extracts, the biological attributes of the lipophilic fraction remain unknown. Moreover, only a limited number of active compounds have so far been identified. This work aimed to investigate the anti-oxidative, anti-aggregation, and cytotoxic properties as well as profile the secondary metabolites in the lipophilic fraction of E. camaldulensis leaf extract (Lipo-Eucam) using UHPLC-ESI-QTOF-MS and gas chromatography-mass spectrometry (GC-MS). It was found that Lipo-Eucam possessed potent antioxidant properties against DPPH, ABTS, and FRAP with IC₅₀ values of 31.46, 32.78, and 10.12 μg/mL, respectively. The fraction was able to attenuate metal-catalyzed oxidation of bovine serum albumin (BSA) in a dose-dependent manner (p < 0.05) and abrogated the aggregation of amyloidogenic BSA as revealed by the Congo red assay and transmission electron microscopy. Furthermore, Lipo-Eucam demonstrated potent cytotoxic effects against MCF-7 (IC₅₀ 7.34 μg/mL) but was noncytotoxic at used concentrations against HEK-293 cells (IC₅₀ > 80 μg/mL), suggestive of its selective anticancer properties. Spectrophotometric, UHPLC-MS, and GC-MS analysis revealed that Lipo-Eucam is rich in phenolics, flavonoids, terpenoids, volatile constituents, and a plethora of active metabolites, probably responsible for the observed activities. These findings indicate that Lipo-Eucam is endowed with pharmacologically relevant active principles with strong potential for use in the amelioration of disease conditions related to oxidative stress, protein aggregation, and breast cancer and therefore worthy of further investigations.

Establishing and characterizing a novel doxorubicin-resistant acute myeloid leukaemia cell line

Drug resistance is a major setback in cancer treatment, thus models to study its mechanisms are needed. Our work aimed to establish and characterize a resistant cell line from a sensitive acute myeloid leukaemia (AML) cell line - HL60 - by treating the sensitive cells with increasing concentrations of doxorubicin. We confirmed (cell viability assays) that the established subline, HL60-CDR, was resistant to doxorubicin for at least 30 days without drug treatment. The HL60-CDR cells were also resistant to three other drugs (cisplatin, etoposide and daunorubicin), exhibiting a multidrug resistant (MDR) profile. We verified (Western Blotting) that the MDR cells do not express drug efflux pumps, nor present altered expression of apoptotic proteins, when compared with the parental cell line. HL60-CDR cells presented alterations in the cell cycle profile, and in the expression levels of proteins involved in DNA repair mechanisms and drug metabolism, when compared with their drug sensitive counterpart. Proteomic analysis revealed that HL60-CDR cells presented an upregulation of proteins involved in oncogenic pathways, such as TSC2, PDPK1, Annexin A2, among others. Overall, we established an AML MDR subline - HL60-CDR - which presents several resistance mechanisms, providing an in vitro model to test new compounds to circumvent MDR in AML.

Prospective Medicinal Plants and Their Phytochemicals Shielding Autoimmune and Cancer Patients Against the SARS-CoV-2 Pandemic: A Special Focus on Matcha

Background

Being "positive" has been one of the most frustrating words anyone could hear since the end of 2019. This word had been overused globally due to the high infectious nature of SARS-CoV-2. All citizens are at risk of being infected with SARS-CoV-2, but a red warning sign has been directed towards cancer and immune-compromised patients in particular. These groups of patients are not only more prone to catch the virus but also more predisposed to its deadly consequences, something that urged the research community to seek other effective and safe solutions that could be used as a protective measurement for cancer and autoimmune patients during the pandemic.

Aim

The authors aimed to turn the spotlight on specific herbal remedies that showed potential anticancer activity, immuno-modulatory roles, and promising anti-SARS-CoV-2 actions.

Methodology

To attain the purpose of the review, the research was conducted at the States National Library of Medicine (PubMed). To search databases, the descriptors used were as follows: "COVID-19"/"SARS-CoV-2", "Herbal Drugs", "Autoimmune diseases", "Rheumatoid Arthritis", "Asthma", "Multiple Sclerosis", "Systemic Lupus Erythematosus" "Nutraceuticals", "Matcha", "EGCG", "Quercetin", "Cancer", and key molecular pathways.

Results

This manuscript reviewed most of the herbal drugs that showed a triple action concerning anticancer, immunomodulation, and anti-SARS-CoV-2 activities. Special attention was directed towards "matcha" as a novel potential protective and therapeutic agent for cancer and immunocompromised patients during the SARS-CoV-2 pandemic.

Conclusion

This review sheds light on the pivotal role of "matcha" as a tri-acting herbal tea having a potent antitumorigenic effect, immunomodulatory role, and proven anti-SARS-CoV-2 activity, thus providing a powerful shield for high-risk patients such as cancer and autoimmune patients during the pandemic.

New Monoterpene Acid and Gallic Acid Glucose Esters with Anti-Inflammatory Activity from Blue Gum (Eucalyptus globulus) Leaves

Blue gum (Eucalyptus globulus) is a widely used botanical in the cosmeceutical and food industries. Although blue gum leaves are known for abundant essential oils, their nonvolatile phytochemical constituents and bioactivities remain unclear. Herein, a phytochemical investigation of blue gum leaves led to the identification of eight new monoterpene acid and gallic acid glucose esters (1-4 and 14-17; glubosides A-H, respectively) and 12 known analogues (5-13 and 18-20). Their structures were determined based on extensive spectroscopic data analysis, chemical degradation, and chiral separation. Oleuropeic acid conjugated glucose esters (1-13, 15, 16, 18, and 20) are reported as epimeric mixtures. Compounds 7, 12, 14, 19, and 20 (at 30 μM) inhibited nitrite release in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Compounds 7 and 14 (at 3-30 μM) also down-regulated proinflammatory biomarkers, including cytokines (TNF-α, IL-6, and IL-1β), protein expression (iNOS and COX-2), and transcription factor nuclear translocation (NF-κB) in LPS-stimulated RAW264.7 cells. This work highlights the anti-inflammatory potential of phytochemicals from blue gum leaves, which supports their further development as cosmeceutical and/or nutraceutical products.

Pirfenidone Sensitizes NCI-H460 Non-Small Cell Lung Cancer Cells to Paclitaxel and to a Combination of Paclitaxel with Carboplatin

Pirfenidone, an antifibrotic drug, has antitumor potential against different types of cancers. Our work explored whether pirfenidone sensitizes non-small cell lung cancer (NSCLC) cell lines to chemotherapeutic treatments. The cytotoxic effect of paclitaxel in combination with pirfenidone against three NSCLC cell lines (A549, NCI-H322 and NCI-H460) was evaluated using the sulforhodamine B assay. The effects of this combination on cell viability (trypan blue exclusion assay), proliferation (BrdU incorporation assay), cell cycle (flow cytometry following PI staining) and cell death (Annexin V-FITC detection assay and Western blot) were analyzed on the most sensitive cell line (NCI-H460). The cytotoxic effect of this drug combination was also evaluated against two non-tumorigenic cell lines (MCF-10A and MCF-12A). Finally, the ability of pirfenidone to sensitize NCI-H460 cells to a combination of paclitaxel plus carboplatin was assessed. The results demonstrated that pirfenidone sensitized NCI-H460 cells to paclitaxel treatment, reducing cell growth, viability and proliferation, inducing alterations in the cell cycle profile and causing an increase in the % of cell death. Remarkably, this combination did not increase cytotoxicity in non-tumorigenic cells. Importantly, pirfenidone also sensitized NCI-H460 cells to paclitaxel plus carboplatin. This work highlights the possibility of repurposing pirfenidone in combination with chemotherapy for the treatment of NSCLC.

Cheminformatics Application in the Phytochemical and Biological Study of Eucalyptus globulus L. Bark as a Potential Hepatoprotective Drug

Natural products are considered as a good source of antifibrotic agents, but identifying and isolating bioactive molecule(s) is still challenging. Fortunately, numerous computational techniques have evolved to save time and efforts in this field. The aim of the current study was to utilize several cheminformatics software to study the chemical and biological features of the bark of Eucalyptus globulus cultivated in Egypt. Sirius software, with the aid of online databases, was used to process liquid chromatography-mass spectrometry (LC-MS) chemical profiling and predict precise molecular formulae, chemical classes, and structures. Accordingly, 37 compounds were tentatively identified, including 15 reported here for the first time from this species. Also, the BioTransformer tool was successfully applied for in silico virtual study of the human metabolism of these compounds, and 1960 different products were obtained through various metabolic pathways. Finally, an electronic library of the identified compounds and their metabolites were developed and docked in silico against eight different protein targets that are involved in the liver fibrosis process. The results revealed that the extract may have a potential hepatoprotective effect through several mechanisms and that the metabolites have the highest binding affinities to the relevant enzymes than their parent compounds. The extract was found to show potent cytotoxic activity against the liver cancer cell lines HEPG2 and HUH-7, and its absorption was enhanced through nanoformulation, as proved using the ex vivo everted gut sac method.

Synthesis of Novel Methyl 7-[(Hetero)arylamino]thieno[2,3-b]pyrazine-6-carboxylates and Antitumor Activity Evaluation: Effects in Human Tumor Cells Growth, Cell Cycle Analysis, Apoptosis and Toxicity in Non-Tumor Cells

Several novel methyl 7-[(hetero)arylamino]thieno[2,3-b]pyrazine-6-carboxylates were synthesized by Pd-catalyzed C–N Buchwald–Hartwig cross-coupling of either methyl 7-aminothieno[3,2-b]pyrazine-6-carboxylate with (hetero)arylhalides or 7-bromothieno[2,3-b]pyrazine-6-carboxylate with (hetero)arylamines in good-to-excellent yields (50% quantitative yield), using different reaction conditions, namely ligands and solvents, due to the different electronic character of the substrates. The antitumoral potential of these compounds was evaluated in four human tumor cell lines: gastric adenocarcinoma (AGS), colorectal adenocarcinoma (CaCo-2), breast carcinoma (MCF7), and non-small-cell lung carcinoma (NCI-H460) using the SRB assay, and it was possible to establish some structure–activity relationships. Furthermore, they did not show relevant toxicity against a non-tumor cell line culture from the African green monkey kidney (Vero). The most promising compounds (GI₅₀ ≤ 11 µM), showed some selectivity either against AGS or CaCo-2 cell lines without toxicity at their GI₅₀ values. The effects of the methoxylated compounds 2b (2-OMeC₆H₄), 2f and 2g (3,4- or 3,5-diOMeC₆H₃, respectively) on the cell cycle profile and induction of apoptosis were further studied in the AGS cell line. Nevertheless, even for the most active (GI₅₀ = 7.8 µM) and selective compound (2g) against this cell line, it was observed that a huge number of dead cells gave rise to an atypical distribution on the cell cycle profile and that these cells were not apoptotic, which points to a different mechanism of action for the AGS cell growth inhibition.

Synthesis of Novel Methyl 3-(hetero)arylthieno[3,2-b]pyridine-2-carboxylates and Antitumor Activity Evaluation: Studies In Vitro and In Ovo Grafts of Chick Chorioallantoic Membrane (CAM) with a Triple Negative Breast Cancer Cell Line

A series of novel functionalized methyl 3-(hetero)arylthieno[3,2-b]pyridine-2-carboxylates 2a–2h were synthesized by C-C Pd-catalyzed Suzuki-Miyaura cross-coupling of methyl 3-bromothieno[3,2-b]pyridine-2-carboxylate with (hetero)aryl pinacol boranes, trifluoro potassium boronate salts or boronic acids. Their antitumoral potential was evaluated in two triple negative breast cancer (TNBC) cell lines—MDA-MB-231 and MDA-MB-468, by sulforhodamine B assay. Their effects on the non-tumorigenic MCF-12A cells were also evaluated. The results demonstrated that three compounds caused growth inhibition in both TNBC cell lines, with little or no effect against the non-tumorigenic cells. The most promising compound was further studied concerning possible effects on cell viability (by trypan blue exclusion assay), cell proliferation (by bromodeoxyuridine assay) and cell cycle profile (by flow cytometry). The results demonstrated that the GI₅₀ concentration of compound 2e (13 μM) caused a decreased in MDA-MB-231 cell number, which was correlated with a decreased in the % of proliferating cells. Moreover, this compound increased G0/G1 phase and decreased S phases, when compared to control cells (although was not statistic significant). Interestingly, compound 2e also reduced tumor size using an in ovo CAM (chick chorioallantoic membrane) model. This work highlights the potential antitumor effect of a novel methyl 3-arylthieno[3,2-b]pyridine-2-carboxylate derivative.

Value-Added Compound Recovery from Invasive Forest for Biofunctional Applications: Eucalyptus Species as a Case Study

From ancient times, the medicinal properties of the different Eucalyptus species are well known. In fact, plants from this family have been used in folk medicine as antiseptics, and to treat different ailments of the upper respiratory tract such as sinus congestion, common cold, or influenza. Moreover, other biological activities were described for Eucalyptus species such as antioxidant and antimicrobial properties. In the last few decades, numerous investigations revealed that the compounds responsible for these properties are secondary metabolites that belonging to the group of phenolic compounds and are present in different parts of the plants such as leaves, bark, wood, fruits, and stumps. The increasing demand for natural compounds that can substitute synthetic antioxidants and the increase in resistance to traditional antibiotics have boosted the intense search for renewable natural sources containing substances with such bioactivities, as well as greener extraction technologies and avant-garde analytical methods for the identification of the target molecules. The literature data used in this paper were collected via Scopus (2001-2020) using the following search terms: Eucalyptus, extraction methods, phenolic compounds, and biological activities. This review collects the main studies related to the recovery of value-added compounds from different Eucalyptus species, as well as their biofunctional applications.

Molecular Insights into Potential Contributions of Natural Polyphenols to Lung Cancer Treatment

Naturally occurring polyphenols are believed to have beneficial effects in the prevention and treatment of a myriad of disorders due to their anti-inflammatory, antioxidant, antineoplastic, cytotoxic, and immunomodulatory activities documented in a large body of literature. In the era of molecular medicine and targeted therapy, there is a growing interest in characterizing the molecular mechanisms by which polyphenol compounds interact with multiple protein targets and signaling pathways that regulate key cellular processes under both normal and pathological conditions. Numerous studies suggest that natural polyphenols have chemopreventive and/or chemotherapeutic properties against different types of cancer by acting through different molecular mechanisms. The present review summarizes recent preclinical studies on the applications of bioactive polyphenols in lung cancer therapy, with an emphasis on the molecular mechanisms that underlie the therapeutic effects of major polyphenols on lung cancer. We also discuss the potential of the polyphenol-based combination therapy as an attractive therapeutic strategy against lung cancer.