RESUMO
In pharmaceutical science and drug design the versatility of the pyrrolidine scaffold relating to spatial arrangement, synthetic accessibility and pharmacological profile is a largely explored and most likely interesting one. Nonetheless, few evidences suggest the pivotal role of pyrrolidine as scaffold for multipotent agents in neurodegenerative diseases. We then challenged the enrolling in the field of Alzheimer disease of so far not ravelled targets of this chemical cliché with a structure based and computer-aided design strategy focusing on multi-target action, versatile synthesis as well as pharmacological safeness. To achieve these hits, ten enantiomeric pairs of compounds were obtained and tested, and the biological data will be here presented and discussed. Among the novel compounds, coumarin and sesamol scaffolds containing analogues resulted promising perspectives.
Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Pirrolidinas , Pirrolidinas/química , Pirrolidinas/síntese química , Pirrolidinas/farmacologia , Humanos , Doença de Alzheimer/tratamento farmacológico , Doenças Neurodegenerativas/tratamento farmacológico , Estereoisomerismo , Estrutura Molecular , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/síntese química , Animais , Relação Estrutura-AtividadeRESUMO
Cadmium (Cd) toxicity poses a significant threat to cellular health, leading to oxidative stress and cell damage. Antioxidant agents, particularly those of natural origin, have been studied as a potential alternative for mitigating heavy metal toxicity. This study aimed to evaluate the cytoprotective effects of the antioxidant melatonin (MLT) in comparison with Vitamin E (VitE) and Trolox against Cd2+-induced cellular toxicity. The MTT assay was employed to assess cell viability in neuronal SH-SY5Y, colorectal HCT 116, and hepatic HepG2 cell lines. The results showed that all three antioxidants offered some level of protection against Cd toxicity, with Vitamin E proving to be the most effective. MLT also demonstrated a substantial cytoprotective effect, especially at the highest Cd concentration of 30 µM. These findings suggest that MLT, alongside Vit E and Trolox, could be valuable in mitigating the detrimental effects of Cd exposure by reducing the oxidative stress in these cellular models.
Assuntos
Antioxidantes , Cádmio , Sobrevivência Celular , Cromanos , Melatonina , Estresse Oxidativo , Vitamina E , Humanos , Melatonina/farmacologia , Cromanos/farmacologia , Vitamina E/farmacologia , Cádmio/toxicidade , Antioxidantes/farmacologia , Células Hep G2 , Estresse Oxidativo/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Células HCT116 , Linhagem Celular TumoralRESUMO
Spirulina, a filamentous microalga, is used all over the world as a nutraceutical dietary supplement. Recent studies have focused on examining its chelating activity and antioxidant properties, especially as a candidate for protection against neurotoxicity caused by heavy metals. The MTT test and LDH assay were used to examine the viability of the SH-SY5Y cells for 24, 48, and 72 h, to Cd, Hg, and Pb, individually or in combination with Spirulina, and the effects of necrotic cell death. In comparison to the control group, the viability of SH-SY5Y cells decreased after 24 h of exposure, with Cd being more toxic than Hg and Pb being less lethal. The effects of heavy metal toxicity on cell survival were ranked in order after 72 h under identical experimental circumstances as follows: Hg, Pb, and Cd. The viability of the cells was then tested after being exposed to Spirulina at doses of 5 at 50 (%v/v) for 24, 48, and 72 h, respectively. SH-SY5Y cells that had been treated with mixtures of heavy metals and Spirulina underwent the same assay. Cell viability is considerably increased by using Spirulina treatments at the prescribed periods and doses. Instead, the same procedure, when applied to SH-SY5Y cells, caused the release of LDH, which is consistent with the reduction in cell viability. We demonstrated for the first time, considering all the available data, that Spirulina 5, 25, and 50 (%v/v) enhanced the number of viable SH-SY5Y cells utilized as a model system for brain cells. Overall, the data from the present study provide a first insight into the promising positive role of Spirulina against the potentially toxic effects of metals.
Assuntos
Mercúrio , Metais Pesados , Neuroblastoma , Spirulina , Humanos , Mercúrio/toxicidade , Cádmio/toxicidade , Chumbo/farmacologia , Metais Pesados/toxicidade , Linhagem Celular Tumoral , Sobrevivência CelularRESUMO
Lipids from milk are important nutritional components, although their health effects, especially for animal milks, are still questioned. Four types of commercial milks, two semi-skimmed animal milks (bovine and goat) and two vegetable ones (soy and rice), along with their total and free lipid fractions recovered by sequential centrifugation or by ethyl acetate extraction, respectively, have been analyzed. A higher antioxidant ability, reported as Trolox equivalent antioxidant capacity, was found for all raw milks compared to that of rice. This trend was confirmed, except for soy milk, as ROS reduction in Caco-2 cells. The free lipid fraction was shown to have the highest antioxidant potential in both chemical and biological tests. Moreover, goat and soy raw milks positively regulated Caco-2 cell viability after an inflammatory stimulus. This effect was lost when their total lipid fraction was tested. Finally, only the free lipid fraction from rice milk preserved the Caco-2 viability after LPS stimulation. Our data demonstrated that the lipid profile of each milk, characterized by GC-MS analysis, could contribute to dictate its biological effects, and, although additional in vitro and in vivo studies are needed, they could support the literature re-evaluating the health effects of animal-based versus plant-based milks in the intestinal cellular model.
Assuntos
Antioxidantes , Verduras , Células CACO-2 , Sobrevivência Celular , Fermentação , Humanos , Intestinos/efeitos dos fármacosRESUMO
Cancer is a complex issue and, even though the prevention basics and therapy have been implemented, it is still the second leading death cause worldwide. With the hope to discover new powerful and safer molecules to fight cancer, many researchers focused their attention on metal-based compounds, starting from the most famous and successfully employed anticancer drug, i.e. cisplatin. The current article aims to report the most recent discoveries about the use of gold, silver and copper complexes as antitumor agents, highlighting their influences on important enzymes, namely human topoisomerases. The latter are fundamental for the cell life and, if overexpressed, strongly implicated in cancer onset and progression. The identification of lead complexes targeting human topoisomerases and gifted with the appropriate chemical and pharmacological properties represents a fecund starting point to obtain new and more effective anticancer molecules.
Assuntos
Complexos de Coordenação/química , Cobre/química , DNA Topoisomerases/química , Ouro/química , Prata/química , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/metabolismo , Complexos de Coordenação/farmacologia , DNA Topoisomerases/metabolismo , Humanos , Ligantes , Relação Estrutura-AtividadeRESUMO
The indole scaffold has been recognized, over the years, as a model for the synthesis of compounds with anticancer activity by dint of its substantiated ability to act via multiple mechanisms, which also involves the inhibition of enzymes engaged in DNA replication. In this regard, a new series of indole and pyranoindole derivatives have been prepared, some of which showed good antitumor activity and proved their inhibitory effects on the tubulin target. The anticancer activity of the newly synthesized compounds has been evaluated on breast cancer cell lines, as MCF-7 and MDA-MB231, cervical cancer cells line HeLa and Ishikawa endometrial cancer cell line. Among the compounds under study, 7 exhibited a good antitumor activity on HeLa cell line (IC50 = 3.6 ± 0.5), leading to cell death by apoptosis due to the inhibition of tubulin polymerization, which demonstrated that the compound can explicate its function in a similar way to Vinblastine, a well-known inhibitor of tubulin polymerization. The data were also confirmed by in silico assays. No cytotoxicity against normal cells has been detected. Furthermore, in order to investigate the antioxidant properties, DPPH and ABTS tests were performed, together with fluorescence assays on 3T3-L1 cells. All our findings taken together led us to consider compound 7 a favourable candidate for the battle against cancer.
Assuntos
Antineoplásicos/síntese química , Antioxidantes/síntese química , Indóis/síntese química , Moduladores de Tubulina/síntese química , Tubulina (Proteína)/metabolismo , Células 3T3 , Animais , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Apoptose , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Peróxido de Hidrogênio/metabolismo , Indóis/farmacologia , Camundongos , Simulação de Acoplamento Molecular , Estrutura Molecular , Espécies Reativas de Oxigênio/metabolismo , Moduladores de Tubulina/farmacologiaRESUMO
Ellagic acid (EA), a polyphenolic constituent of plant origin, has been thoroughly investigated for its hypothesised pharmacological properties among which antioxidant and neuroprotective activities are included. The present study was designed to explore whether EA could attenuate heavy metal (cadmium, mercury, and lead)-induced neurotoxicity in SH-SY5Y cells, which were utilized as a model system for brain cells. MTT and LDH assays were performed to examine the viability of the SH-SY5Y cells after exposure to Cd, Hg, and Pb (either individually or in combination with EA) as well as the effects of necrotic cell death, respectively. Furthermore, 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA), a cell-based assay, was performed to determine whether EA could protect SH-SY5Y from heavy metal-induced oxidative stress. Results allowed us to assess the capability of EA to enhance the number of viable SH-SY5Y cells after exposure to heavy metal toxicity. Pre-treatment with EA showed a considerable, concentration-dependent, cytoprotective effect, particularly against Cd2+-induced toxicity. This effect was confirmed through the reduction of LDH release after the simultaneous cell treatment with Cd2+ and EA compared with Cd2+-treated cells. Furthermore, a significant, concentration-dependent decrease in reactive oxygen species (ROS) production, induced by H2O2 or heavy metals, was observed in the same model. Overall, the obtained results provide further insight into the protective role of EA against heavy metal-induced neurotoxicity and oxidative stress, thus indicating the potential beneficial effects of the consumption of EA-rich foods. However, to confirm its effects, well-designed human randomized controlled trials are needed to fill the existing gap between experimental and clinical research.
RESUMO
The present study aims to highlight the cell protective effect of Tropea red onion (TRO) hydroalcoholic extract and some of its components against "non-essential" heavy metals. For this purpose, the cytoprotective roles of cyanidin, cyanidin-3-O-glucoside and quercetin against Cd, Hg and Pb and of TRO extract against Hg and Pb have been investigated, and data are reported here. To the best of our knowledge, this is the first detailed evaluation of the protective effect against cell damage induced by "non-essential" heavy metals through the simultaneous administration of cyanidin, cyanidin-3-O-glucoside and quercetin with CdCl2, HgCl2 or PbCl2 and the TRO extract against HgCl2 and PbCl2. Present data are also compared with our previous results from the TRO extract against Cd. The antioxidant capacity of the extract was also determined by the ferric reducing antioxidant power (FRAP) and the bovine brain peroxidation assay. Both of the assays indicated a good antioxidant capacity of the extract. Cell viability and the impact on necrotic cell death were examined by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) test and lactate dehydrogenase (LDH) release assay. After 24 h of exposure, Caco-2 cell viability decreased by approximately 50% at 0.25 µM for Cd, Hg and Pb and, after 72 h, the ranking order of "non-essential" heavy metal toxicity on cell viability was PbCl2 > CdCl2 > HgCl2. Cell viability was assessed by treating the cells with the biomolecules at doses of 25, 50 and 100 µg/mL for 24 and 72 h. The same analysis was carried out on Caco-2 cells treated with combinations of TRO extract, cyanidin, cyanidin-3-O-glucoside, or quercetin and "non-essential" heavy metals. Treatments with the bioactive metabolites did not significantly improve cell viability. The identical treatment of Caco-2 cells produced instead LDH release, suggesting a decrease in cell viability. Consistently with the finding that TRO extract showed a good antioxidant activity, we suggest that its higher cytotoxicity, compared to that of the individual assayed phytochemicals, may be derived by the combined antioxidant and chelating properties of all the molecules present in the extract. Therefore, from all the acquired experimental evidence, it appears that the TRO extract may be a better promising protective agent against the toxic effect of Cd, Hg and Pb compared to its bioactive metabolites.
RESUMO
The emergence and spread of drug-resistant pathogens, resulting in antimicrobial resistance, continue to compromise our capability to handle commonly occurring infectious diseases. The rapid global spread of multi-drug-resistant pathogens, particularly systemic fungal infections, presents a significant concern, as existing antimicrobial drugs are becoming ineffective against them. In recent decades, there has been a notable increase in systemic fungal infections, primarily caused by Candida species, which are progressively developing resistance to azoles. Moreover, Candida species biofilms are among the most common in clinical settings. In particular, they adhere to biomedical devices, growing as a resilient biofilm capable of withstanding extraordinarily high antifungal concentrations. In recent years, many research programs have concentrated on the development of novel compounds with possible antimicrobial effects to address this issue, and new sources, such as plant-derived antimicrobial compounds, have been thoroughly investigated. Essential oils (EOs), among their numerous pharmacological properties, exhibit antifungal, antibacterial, and antiviral activities and have been examined at a global scale as the possible origin of novel antimicrobial compounds. A recent work carried out by our research group concerned the synergistic antibacterial activities of commercially available and chemically characterized Cinnamomum verum L. essential oil (C. verum EO) in association with sertraline, a selective serotonin reuptake inhibitor whose repositioning as a non-antibiotic drug has been explored over the years with encouraging results. The aim of this work was to explore the synergistic effects of C. verum EO with sertraline on both planktonic and sessile Candida species cells. Susceptibility testing and testing of the synergism of sertraline and C. verum EO against planktonic and sessile cells were performed using a broth microdilution assay and checkerboard methods. A synergistic effect was evident in both the planktonic cells and mature biofilms, with significant reductions in fungal viability. Indeed, the fractional inhibitory concentration index (FICI) was lower than 0.5 for all the associations, thus indicating significant synergism of the associations with the Candida strains examined. Moreover, the concentrations of sertraline able to inhibit Candida spp. strain growth and biofilm formation significantly decreased when it was used in combination with C. verum EO for all the strains considered, with a reduction percentage in the amount of each associated component ranging from 87.5% to 97%.
RESUMO
Waste from the agri-food chain represents a valuable reservoir of organic compounds with health-promoting properties. Momast Plus 30 Bio (MP30B) is a derivative obtained from olive-oil wastewater. Its enrichment in hydroxytyrosol (HT) via a patented technique has paved the way for its potential application as a dietary supplement in preventing cardiovascular diseases. MP30B demonstrates no significant alteration in cardiac and vascular parameters in "ex vivo" studies. However, it exhibits a strong ability to remove reactive oxygen species and exerts anti-inflammatory effects, notably reducing the concentration of iNOS and mitigating heart infections in "in vitro" experiments. Furthermore, MP30B slightly decreases the stiffness of the "ex vivo" thoracic aorta, potentially resulting in lowered arterial pressure and enhanced energy transfer to a normal ventricle. Based on these findings, we posit MP30B as a promising extract for cardiovascular disease prevention, and its specific antibacterial properties suggest its utility in preventing cardiac infections.
Assuntos
Doenças Cardiovasculares , Olea , Águas Residuárias , Águas Residuárias/química , Doenças Cardiovasculares/prevenção & controle , Olea/química , Humanos , Azeite de Oliva/química , Animais , Álcool Feniletílico/análogos & derivados , Álcool Feniletílico/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Suplementos Nutricionais , Resíduos Industriais/análise , Anti-Inflamatórios/farmacologiaRESUMO
This study explores how a simple argentometric titration-like approach could be evolved into a versatile, scalable, fast, and robust strategy for the production of AgCl/quaternary ammonium compounds (QACs) colloidal nanoantimicrobials (NAMs). These systems, which are green, stable, cost-effective, and reproducible are found to be effective against a wide range of food pathogenic bacteria and biofilms. The option of a large-scale production for such colloidal suspensions was explored via the use of a peristaltic pump. The utilization of various types of biosafe QACs and a wide range of solvents including aqueous and organic ones renders this system green and versatile. Nanocolloids (NCs) were characterized using UV-Vis, X-ray photoelectron and Fourier transform infrared (FTIR) spectroscopies. Their morphology and crystalline nature were investigated by transmission electron microscopy (TEM) and selected area diffraction pattern (SAED). Nanoparticle (NP) size distribution and hydrodynamic radius were measured by dynamic light scattering (DLS), while the ζ-potential was found to be highly positive, thus indicating significant colloidal stability and antimicrobial activity. In fact, the higher the NP surface charge, the stronger was their bioactivity. Furthermore, the antibacterial and antibiofilm effects of the as-prepared NCs were tested against Gram-positive bacteria, such as Staphylococcus aureus (ATCC 29213) and Listeria monocytogenes 46, and Gram-negative bacteria, such as Escherichia coli (ATCC 25922) and Pseudomonas aeruginosa (ATCC 27853). The results clearly indicate that AgCl/QACs provide pronounced antibiofilm activity with long-term bacteriostatic effects against foodborne pathogenic bacteria rendering them an ideal choice for active food packaging systems.
RESUMO
Oxidative stress has been reported to be involved in the onset and development of several diseases, including neurodegenerative and cardiovascular disorders, some types of cancer, and diabetes. Therefore, finding strategies to detoxify free radicals is an active area of research. One of these strategies is the use of natural or synthetic antioxidants. In this context, melatonin (MLT) has been proven to possess most of the required characteristics of an efficient antioxidant. In addition, its protection against oxidative stress continues after being metabolized, since its metabolites also exhibit antioxidant capacity. Based on the appealing properties of MLT and its metabolites, various synthetic analogues have been developed to obtain compounds with higher activity and lower side effects. This review addresses recent studies with MLT and related compounds as potential antioxidants.
RESUMO
The benzothiazole nucleus is a major heterocyclic scaffold whose therapeutic potential has been thoroughly explored due to its structural simplicity and ease of synthesis. In fact, several benzothiazole derivatives have been synthesized over time, demonstrating numerous pharmacological properties such as anticancer, antimicrobial, anti-inflammatory, and antioxidant activities. Herein, we propose a new series of benzothiazole-phthalimide hybrids obtained by linking the phthalimide moiety to differently substituted benzothiazole nuclei through the N atom. These compounds have been screened for their anticancer properties against two human breast cancer cell lines. Furthermore, we delved into the mechanism of action of the most active hybrid, compound 3h, by assessing its capability to damage the nuclear DNA, trigger the apoptotic process in the high metastatic MDA-MB-231 cells, and prevent cellular migration. Moreover, in view of the documented antimicrobial activities of the two scaffolds involved, we explored the antibacterial and antifungal effects of the studied compounds by means of the broth microdilution method. Among the studied compounds, 3h showed the highest antimicrobial activity, both against gram-positive and gram-negative bacterial strains belonging to the ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) and against fungal strains of the Candida species with MICs values ranging from 16 to 32 µg/mL.
RESUMO
Systemic fungal infections have risen in recent decades and most of them are caused by Candida species, which are becoming increasingly resistant to conventional antifungal drugs. Biofilm production has been considered the most common growth form of Candida cells and is associated with a high level of antifungal resistance. At present, international research reports on the antifungal activity of non-traditional antimicrobial drugs and their potential use against life-threatening resistant fungal infections. Indeed, drug repurposing has led to the consideration of well-known compounds as a last-line therapy. The goal of this work is to evaluate the potential synergistic antifungal biofilm activity of new combinations between diclofenac sodium salt (DSS), a widely used non-steroidal anti-inflammatory drug (NSAID), with the essential oils (EOs) of Mentha piperita, Pelargonium graveolens, and Melaleuca alternifolia, whose antifungal activity has been well documented over the years. The in vitro antifungal activity of DSS and EOs was determined on different Candida strains. Susceptibility testing and the synergism of DSS and EOs versus biofilm cells was performed by using the broth microdilution assay and checkerboard methods. Minimum inhibitory concentrations (sMIC50) of DSS alone ranged from 1.25 to 2.05 mg/mL for all the strains considered. These values significantly decreased when the drug was used in combination with the EOs. The fractional inhibitory concentration index (FICI) was lower than 0.5 for almost all the associations, thus indicating a significant synergism, particularly for the DSS-Pelargonium graveolens combination towards the Candida strains examined. These preliminary results show that the combination of the EOs with DSS improves the antifungal activity on all the tested Candida strains, significantly lowering the concentrations of the components used and thus allowing any toxic effects to be overcome.
RESUMO
Alzheimer's disease is becoming a growing problem increasing at a tremendous rate. Serotonin 5-HT6 receptors appear to be a particularly attractive target from a therapeutic perspective, due to their involvement not only in cognitive processes, but also in depression and psychosis. In this work, we present the synthesis and broad biological characterization of a new series of 18 compounds with a unique 1,3,5-triazine backbone, as potent 5-HT6 receptor ligands. The main aim of this research is to compare the biological activity of the newly synthesized sulfur derivatives with their oxygen analogues and their N-demethylated O- and S-metabolites obtained for the first time. Most of the new triazines displayed high affinity (Ki < 200 nM) and selectivity towards 5-HT6R, with respect to 5-HT2AR, 5-HT7R, and D2R, in the radioligand binding assays. For selected, active compounds crystallographic studies, functional bioassays, and ADME-Tox profile in vitro were performed. The exciting novelty is that the sulfur derivatives exhibit an agonistic mode of action contrary to all other compounds obtained to date in this chemical class herein and previously reported. Advanced computational studies indicated that this intriguing functional shift might be caused by presence of chalcogen bonds formed only by the sulfur atom. In addition, the N-demethylated derivatives have emerged highly potent antioxidants and, moreover, show a significant improvement in metabolic stability compared to the parent structures. The cholinesterase study present micromolar inhibitory AChE and BChE activity for both 5-HT6 agonist 19 and potent antagonist 5. Finally, the behavioral experiments of compound 19 demonstrated its antidepressant-like properties and slight ability to improve cognitive deficits, without inducing memory impairments by itself. Described pharmacological properties of both compounds (5 and 19) allow to give a design clue for the development of multitarget compounds with 5-HT6 (both agonist and antagonist)/AChE and/or BChE mechanism in the group of 1,3,5-triazine derivatives.
Assuntos
Doença de Alzheimer , Calcogênios , Humanos , Doença de Alzheimer/tratamento farmacológico , Serotonina , Estrutura Molecular , Relação Estrutura-Atividade , Receptores de Serotonina/metabolismo , Ligantes , Triazinas/química , Éteres , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/uso terapêutico , Acetilcolinesterase/metabolismoRESUMO
INTRODUCTION: Thalidomide is an old well-known drug firstly used as morning sickness relief in pregnant women and then withdrawn from the market due to its severe side effects on fetal normal development. However, over the last few decades, the interest in this old drug has been renewed because of its efficacy in several important disorders as, for instance, multiple myeloma, breast cancer, and HIV-related diseases due to its antiangiogenic and immunomodulatory properties. Unfortunately, even in these cases, many after effects as deep vein thrombosis, peripheral neuropathy, constipation, somnolence, pyrexia, pain, and teratogenicity have been reported showing the requirement of careful and monitored use. For this reason, research efforts are geared toward the synthesis and optimization of new thalidomide analogues lacking in toxic effects, able to erase these limits and improve the pharmacological profile. AIMS: This review aims to examine the state-of-the-art concerning the current studies on thalidomide and its analogues towards cancer diseases focusing the attention on the possible mechanisms of action involved and the lack of toxicity. CONCLUSION: In the light of the collected data, thalidomide analogues and their ongoing optimization could lead, in the future, to the realization of a promising therapeutic alternative for fighting cancer.
Assuntos
Antineoplásicos , Mieloma Múltiplo , Doenças do Sistema Nervoso Periférico , Inibidores da Angiogênese/uso terapêutico , Antineoplásicos/uso terapêutico , Feminino , Humanos , Mieloma Múltiplo/tratamento farmacológico , Gravidez , Talidomida/uso terapêuticoRESUMO
The worldwide scenario of antibiotic resistance and the falling number of funds for the development of novel antibiotics have led research efforts toward the study of specific cost-effective strategies aimed at discovering drugs against microbial infections. Among the potential options, drug repositioning, which has already exhibited satisfactory results in other medical fields, came out as the most promising. It consists of finding new uses for previously approved medicines and, over the years, many "repurposed drugs" displayed some encouraging in vitro and in vivo results beyond their initial application. The principal theoretical justification for reusing already existing drugs is that they have known mechanisms of action and manageable side effects. Reuse of old drugs is now considered an interesting approach to overcome the drawbacks of conventional antibiotics. The purpose of this review is to offer the reader a panoramic view of the updated studies concerning the repositioning process of different classes of non-antibiotic drugs in the antimicrobial field. Several research works reported the ability of some non-steroidal anti-inflammatory drugs (NSAIDs), antidepressants, antipsychotics, and statins to counteract the growth of harmful microorganisms, demonstrating an interesting winning mode to fight infectious diseases caused by antimicrobial resistant bacteria.
RESUMO
Cancer represents one of the major causes of mortality worldwide; indeed, 19.3 million new cases and almost 10.0 million deaths were estimated last year. Among the different type of cancers, malignant melanoma represents the most aggressive and deadly skin cancer. Unfortunately, the long-term efficacy of melanoma treatments is limited by the lack of clinical efficacy, onset of side effects and resistance. The latter is a major obstacle for the success of the melanoma therapy; thus, the exploration of new potent and safer anticancer agents is of great importance. Recently, numerous plant species, used for therapeutic purposes and containing various non-toxic nutraceuticals have been widely studied. Herein, we investigated the antioxidant and anticancer properties on melanoma cells of the ethanolic, methanolic and aqueous Annona cherimola leaf extracts (ACE, ACM and ACW, respectively). The ethanolic extract showed higher anticancer activity, mostly against the malignant A2058 melanoma cell line (IC50 = 5.6 ± 0.8 ng/mL), together with a very low activity on the normal cells. It blocks the melanoma cells migration process, and induces a clear disorganization of cytoskeleton, triggering cell apoptosis. Finally, some bioactive compounds were identified in the studied extracts.
RESUMO
Cinnamomum verum L. essential oil (CEO), commonly known as Ceylon cinnamon or cinnamon tree, is regarded as one of the most employed essential oils in the field of aromatherapy. It is usually applied externally as astringent, antipruritic, rubefacient, and anti-septic agent. Furthermore, both in vitro and in vivo research have demonstrated its numerous pharmacological effects, including the potentiality for treating neuralgia, myalgia, headache, and migraine. Several pieces of research also corroborated its significant antiviral and antimicrobial properties. Cinnamaldehyde, eugenol, caryophyllene, cinnamyl acetate, and cinnamic acid are the most representative compounds that are generally found in greater quantities in CEO and play a pivotal role in determining its pharmacological activities. Due to the global antibiotic resistance scenario and the dwindling amount of funding dedicated to developing new antibiotics, in recent years research has concentrated on exploring specific economic approaches against microbial infections. In this context, the purpose of this study was the investigation of the synergistic antibacterial activities of commercially available and chemically characterized CEO in combination with sertraline, a selective serotonin reuptake inhibitor (SSRI), whose repositioning as a non-antibiotic drug has been explored over the years with encouraging results. In vitro effects of the titled combination were assessed toward a wide panel of both Gram-positive and Gram-negative bacteria. The antimicrobial efficacy was investigated by using the checkerboard microdilution method. The interesting preliminary results obtained suggested a synergistic effect (fractional inhibitory index, FICI < 0.5) of sertraline in combination with CEO, leading to severe growth inhibition for all bacterial species under investigation.
RESUMO
Alzheimer's disease (AD) is a complex multi-factorial neurodegenerative disorder for which only few drugs (including donepezil, DPZ) are available as symptomatic treatments; thus, researchers are focusing on the development of innovative multi-target directed ligands (MTDLs), which could also alter the course of the disease. Among other pathological factors, oxidative stress has emerged as an important factor in AD that could affect several pathways involved in the onset and progression of the pathology. Herein, we propose a new series of hybrid molecules obtained by linking a phenothiazine moiety, known for its antioxidant properties, with N-benzylpiperidine or N-benzylpiperazine fragments, mimicking the core substructure of DPZ. The investigation of the resulting hybrids showed, in addition to their antioxidant properties, their activity against some AD-related targets, such as the inhibition of cholinesterases (both AChE and BChE) and in vitro Aß1-40 aggregation, as well as the inhibition of the innovative target fatty acid amide hydrolase (FAAH). Furthermore, the drug-likeness properties of these compounds were assessed using cheminformatic tools. Compounds 11d and 12d showed the most interesting multi-target profiles, with all the assayed activities in the low micromolar range. In silico docking calculations supported the obtained results. Compound 13, on the other hand, while inactive in the DPPH assay, showed the best results in the in vitro antioxidant cell assays conducted on both HepG2 and SHSY-5Y cell lines. These results, paired with the low or absent cytotoxicity of these compounds at tested concentrations, allow us to aim our future research at the study of novel and effective drugs and pro-drugs with similar structural characteristics.