Extract of Araçá-Boi and Its Major Phenolic Compound, Trans-Cinnamic Acid, Reduce Viability and Inhibit Migration of Human Metastatic Melanoma Cells.

Cutaneous melanoma is an aggressive type of skin cancer that is recognized for its high metastatic potential and the challenges it presents in its treatment. There has been increasing interest in plant extracts and their potential applications in melanoma. The present study aimed to investigate the content of individual phenolic compounds in araçá-boi extract, evaluate their antioxidant activity, and explore their effects on cell viability, migration properties, oxidative stress levels, and protein expression in the human metastatic melanoma cell line SK-MEL-28. HPLC-DAD analysis identified 11 phenolic compounds in the araçá-boi extract. Trans-cinnamic acid was the main phenolic compound identified; therefore, it was used alone to verify its contribution to antitumor activities. SK-MEL-28 melanoma cells were treated for 24 h with different concentrations of araçá-boi extract and trans-cinnamic acid (200, 400, 600, 800, and 1600 µg/mL). Both the araçá-boi extract and trans-cinnamic acid reduced cell viability, cell migration, and oxidative stress in melanoma cells. Additionally, they modulate proteins involved in apoptosis and inflammation. These findings suggest the therapeutic potential of araçá-boi extract and its phenolic compounds in the context of melanoma, especially in strategies focused on preventing metastasis. Additional studies, such as the analysis of specific signaling pathways, would be valuable in confirming and expanding these observations.

Defective regulation of the eIF2-eIF2B translational axis underlies depressive-like behavior in mice and correlates with major depressive disorder in humans.

Major depressive disorder (MDD) is a significant cause of disability in adults worldwide. However, the underlying causes and mechanisms of MDD are not fully understood, and many patients are refractory to available therapeutic options. Impaired control of brain mRNA translation underlies several neurodevelopmental and neurodegenerative conditions, including autism spectrum disorders and Alzheimer's disease (AD). Nonetheless, a potential role for mechanisms associated with impaired translational control in depressive-like behavior remains elusive. A key pathway controlling translation initiation relies on the phosphorylation of the α subunit of eukaryotic initiation factor 2 (eIF2α-P) which, in turn, blocks the guanine exchange factor activity of eIF2B, thereby reducing global translation rates. Here we report that the expression of EIF2B5 (which codes for eIF2Bε, the catalytic subunit of eIF2B) is reduced in postmortem MDD prefrontal cortex from two distinct human cohorts and in the frontal cortex of social isolation-induced depressive-like behavior model mice. Further, pharmacological treatment with anisomycin or with salubrinal, an inhibitor of the eIF2α phosphatase GADD34, induces depressive-like behavior in adult C57BL/6J mice. Salubrinal-induced depressive-like behavior is blocked by ISRIB, a compound that directly activates eIF2B regardless of the phosphorylation status of eIF2α, suggesting that increased eIF2α-P promotes depressive-like states. Taken together, our results suggest that impaired eIF2-associated translational control may participate in the pathophysiology of MDD, and underscore eIF2-eIF2B translational axis as a potential target for the development of novel approaches for MDD and related mood disorders.

Nutritional composition, phenolic compounds and biological activities of selected unconventional food plants.

This review highlights the nutritional content, phytochemical compounds, and biological properties of three unconventional food plants consumed in the Amazon: ora-pro-nóbis (Pereskia aculeata Mill.), taioba (Xanthosoma sagittifolium), and vitória-régia (Victoria amazonica). These plants show significant nutritional, functional, and economic potential, which can enhance the intake of daily nutrients, energy, and bioactive compounds. Ora-pro-nóbis is a rich source of caftaric acid, quercetin, and isorhamnetin; taioba contains syringic acid, caffeic acid, and quercetin; and vitória-régia shows cinnamic acid, caffeic acid, and sinapic acid in its composition. These compounds confer antioxidant, anticancer, antimicrobial, anti-inflammatory, analgesic, and antiproliferative properties on these plants. These unconventional plants can be exploited by the food industry as food and supplements and therapeutic plants to develop valuable products for food, cosmetics, pharmaceutical, and medical applications.

Therapeutic Applications of Rosmarinic Acid in Cancer-Chemotherapy-Associated Resistance and Toxicity.

Chemotherapeutic drugs and radiotherapy are fundamental treatments to combat cancer, but, often, the doses in these treatments are restricted by their non-selective toxicities, which affect healthy tissues surrounding tumors. On the other hand, drug resistance is recognized as the main cause of chemotherapeutic treatment failure. Rosmarinic acid (RA) is a polyphenol of the phenylpropanoid family that is widely distributed in plants and vegetables, including medicinal aromatic herbs, consumption of which has demonstrated beneficial activities as antioxidants and anti-inflammatories and reduced the risks of cancers. Recently, several studies have shown that RA is able to reverse cancer resistance to first-line chemotherapeutics, as well as play a protective role against toxicity induced by chemotherapy and radiotherapy, mainly due to its scavenger capacity. This review compiles information from 56 articles from Google Scholar, PubMed, and ClinicalTrials.gov aimed at addressing the role of RA as a complementary therapy in cancer treatment.

Rosmarinic acid turned α-syn oligomers into non-toxic species preserving microtubules in Raw 264.7 cells.

Parkinson's disease (PD) is the second most prevalent neurodegenerative disorder worldwide, and the therapeutic is focused on several approaches including the inhibition of fibril formation by small compounds, avoiding the formation of cytotoxic oligomers. Thus, we decided to explore the capacity of compounds carrying catechol moieties to inhibit the progression of α-synuclein. Overall, the compounds rosmarinic acid (1), carnosic acid (2), carnosol (3), epiisorosmanol (4), and rosmanol (5) avoid the progression of fibril formation assessed by Thiofavine T (ThT), and atomic force microscopy images showed that morphology is influenced for the actions of compounds over fibrillization. Moreover, ITC experiments showed a Kd varying from 28 to 51 µM, the ΔG showed that the reaction between compounds and α-syn is spontaneous, and ΔH is associated with an exothermic reaction, suggesting the interactions of hydrogen bonds among compounds and α-syn. Docking experiments reinforce this idea showing the intermolecular interactions are mostly hydrogen bonding within the sites 2, 9, and 3/13 of α-synuclein, and compounds 1 and 5. Thus, compound 1, rosmarinic acid, interestingly interacts better with site 9 through catechol and Lysines. In cultured Raw 264. 7 cells, the presence of compounds showed that most of them can promote cell differentiation, especially rosmarinic acid, and rosmanol, both preserving tubulin cytoskeleton. However, once we evaluated whether or not the aggregates pre-treated with compounds could prevent the disruption of microtubules of Raw 264.7 cells, only pre-treated aggregates with rosmarinic acid prevented the disruption of the cytoskeleton. Altogether, we showed that especially rosmarinic acid not only inhibits α-syn but stabilizes the remaining aggregates turning them into not-toxic to Raw 264.7 cells suggesting a main role in cell survival and antigen processing in response to external α-syn aggregates.

In silico and in vitro elastase inhibition assessment assays of rosmarinic acid natural product from Rosmarinus officinalis Linn.

The use of various herbs and their compounds has been a strategy widely used in the fight against various human diseases. For example, rosmarinic acid, a bioactive phenolic compound commonly found in Rosemary plants (Rosmarinus officinalis Labiatae), has multiple therapeutic benefits in different diseases, such as cancer. Therefore, the study aimed to evaluate in silico and in vitro the inhibition potential of the enzyme Elastase from the porcine pancreas by rosmarinic acid isolated from the plant species R. officinalis Linn. Through Molecular Docking, the mechanism of action was investigated. In addition, rosmarinic acid presented a range of 5-60 µg/mL and significantly inhibited Elastase. At 60 µg/mL, there was an inhibition of 55% on the enzymatic activity. The results demonstrate the inhibition of Elastase by rosmarinic acid, which can lead to the development of new enzyme inhibitors that can be an inspiration for developing various drugs, including anticancer drugs.

Nanoemulsions and Solid Microparticles Containing Pentyl Cinnamate to Control Aedes aegypti.

The Aedes aegypti mosquito is a vector of severe diseases with high morbidity and mortality rates. The most commonly used industrial larvicides have considerable toxicity for non-target organisms. This study aimed to develop and evaluate liquid and solid carrier systems to use pentyl cinnamate (PC), derived from natural sources, to control Ae. aegypti larvae. The liquid systems consisting of nanoemulsions with different lecithins systems were obtained and evaluated for stability over 30 days. Microparticles (MPs) were obtained by the spray drying of the nanoemulsions using maltodextrin as an adjuvant. Thermal, NMR and FTIR analysis indicated the presence of PC in microparticles. Indeed, the best nanoemulsion system was also the most stable and generated the highest MP yield. The PC larvicidal activity was increased in the PC nanoemulsion system. Therefore, it was possible to develop, characterize and obtain PC carrier systems active against Ae. aegypti larvae.

Finding a Novel Chalcone-Cinnamic Acid Chimeric Compound with Antiproliferative Activity against MCF-7 Cell Line Using a Free-Wilson Type Approach.

In this work, we carried out the design and synthesis of new chimeric compounds from the natural cytotoxic chalcone 2',4'-dihydroxychalcone (2',4'-DHC, A) in combination with cinnamic acids. For this purpose, a descriptive and predictive quantitative structure-activity relationship (QSAR) model was developed to study the chimeric compounds' anti-cancer activities against human breast cancer MCF-7, relying on the presence or absence of structural motifs in the chalcone structure, like in a Free-Wilson approach. For this, we used 207 chalcone derivatives with a great variety of structural modifications over the α and ß rings, such as halogens (F, Cl, and Br), heterocyclic rings (piperazine, piperidine, pyridine, etc.), and hydroxyl and methoxy groups. The multilinear equation was obtained by the genetic algorithm technique, using logIC50 as a dependent variable and molecular descriptors (constitutional, topological, functional group count, atom-centered fragments, and molecular properties) as independent variables, with acceptable statistical parameter values (R2 = 86.93, Q2LMO = 82.578, Q2BOOT = 80.436, and Q2EXT = 80.226), which supports the predictive ability of the model. Considering the aromatic and planar nature of the chalcone and cinnamic acid cores, a structural-specific QSAR model was developed by incorporating geometrical descriptors into the previous general QSAR model, again, with acceptable parameters (R2 = 85.554, Q2LMO = 80.534, Q2BOOT = 78.186, and Q2EXT = 79.41). Employing this new QSAR model over the natural parent chalcone 2',4'-DHC (A) and the chimeric compound 2'-hydroxy,4'-cinnamate chalcone (B), the predicted cytotoxic activity was achieved with values of 55.95 and 17.86 µM, respectively. Therefore, to corroborate the predicted cytotoxic activity compounds A and B were synthesized by two- and three-step reactions. The structures were confirmed by 1H and 13C NMR and ESI+MS analysis and further evaluated in vitro against HepG2, Hep3B (liver), A-549 (lung), MCF-7 (breast), and CasKi (cervical) human cancer cell lines. The results showed IC50 values of 11.89, 10.27, 56.75, 14.86, and 29.72 µM, respectively, for the chimeric cinnamate chalcone B. Finally, we employed B as a molecular scaffold for the generation of cinnamate candidates (C-K), which incorporated structural motifs that enhance the cytotoxic activity (pyridine ring, halogens, and methoxy groups) according to our QSAR model. ADME/tox in silico analysis showed that the synthesized compounds A and B, as well as the proposed chalcones C and G, are the best candidates with adequate drug-likeness properties. From all these results, we propose B (as a molecular scaffold) and our two QSAR models as reliable tools for the generation of anti-cancer compounds over the MCF-7 cell line.

Antileishmanial Activity of Cinnamic Acid Derivatives against Leishmania infantum.

Leishmania infantum is the etiological agent of visceral leishmaniasis (VL) in South America, the Mediterranean basin, and West and Central Asia. The most affected country, Brazil, reported 4297 VL cases in 2017. L. infantum is transmitted by female phlebotomine sand flies during successive blood meals. There are no validated vaccines to prevent the infection and the treatment relies on drugs that often present severe side effects, which justify the efforts to find new antileishmanial drugs. Cinnamic acid derivatives have shown several pharmacological activities, including antiparasitic action. Therefore, in the present study, the biological evaluation of cinnamic acid and thirty-four derivatives against L. infantum is reported. The compounds were prepared by several synthesis methods and characterized by spectroscopic techniques and high-resolution mass spectrometry. The results revealed that compound 32 (N-(4-isopropylbenzyl)cinnamamide) was the most potent antileishmanial agent (IC50 = 33.71 µM) with the highest selectivity index (SI > 42.46), followed by compound 15 (piperonyl cinnamate) with an IC50 = 42.80 µM and SI > 32.86. Compound 32 was slightly less potent and nineteen times more selective for the parasite than amphotericin B (MIC = 3.14 uM; SI = 2.24). In the molecular docking study, the most likely target for the compound in L. infantum was aspartyl aminopeptidase, followed by aldehyde dehydrogenase, mitochondrial. The data obtained show the antileishmanial potential of this class of compounds and may be used in the search for new drug candidates against Leishmania species.

Synthetic Cinnamides and Cinnamates: Antimicrobial Activity, Mechanism of Action, and In Silico Study.

The severity of infectious diseases associated with the resistance of microorganisms to drugs highlights the importance of investigating bioactive compounds with antimicrobial potential. Therefore, nineteen synthetic cinnamides and cinnamates having a cinnamoyl nucleus were prepared and submitted for the evaluation of antimicrobial activity against pathogenic fungi and bacteria in this study. To determine the minimum inhibitory concentration (MIC) of the compounds, possible mechanisms of antifungal action, and synergistic effects, microdilution testing in broth was used. The structures of the synthesized products were characterized with FTIR spectroscopy, 1 H-NMR, 13 C-NMR, and HRMS. Derivative 6 presented the best antifungal profile, suggesting that the presence of the butyl substituent potentiates its biological response (MIC = 626.62 µM), followed by compound 4 (672.83 µM) and compound 3 (726.36 µM). All three compounds were fungicidal, with MFC/MIC ≤ 4. For mechanism of action, compounds 4 and 6 directly interacted with the ergosterol present in the fungal plasmatic membrane and with the cell wall. Compound 18 presented the best antibacterial profile (MIC = 458.15 µM), followed by compound 9 (550.96 µM) and compound 6 (626.62 µM), which suggested that the presence of an isopropyl group is important for antibacterial activity. The compounds were bactericidal, with MBC/MIC ≤ 4. Association tests were performed using the Checkerboard method to evaluate potential synergistic effects with nystatin (fungi) and amoxicillin (bacteria). Derivatives 6 and 18 presented additive effects. Molecular docking simulations suggested that the most likely targets of compound 6 in C. albicans were caHOS2 and caRPD3, while the most likely target of compound 18 in S. aureus was saFABH. Our results suggest that these compounds could be used as prototypes to obtain new antimicrobial drugs.

In silico design, synthesis and evaluation of a less toxic octinoxate alternative with suitable photoprotection properties.

Excessive UV exposure leads to several skin pathologies such as sunburns, photoaging and carcinogenesis. Currently, sunscreen use is the most important factor in protecting skin from photoinduced damage. Octinoxate is a commonly used UV filter, but its use has become controversial because it acts as an endocrine disruptor in both humans, and marine animals. Research has relied on biotechnology, structure activity relationship (SAR) studies and combinatorial chemistry to find new and less toxic UV filters. However, there are no current examples that describe the possible applications of in silico techniques for obtaining these compounds. Thus, this project sought to design an octinoxate analog that could be used as a less toxic, but equally effective, photoprotective alternative through ligand based virtual screening (LBVS). We designed 213 novel molecules based on the (E)-cinnamoyl moiety of octinoxate, but only 23 were found to be less toxic than the parent compound. Then, an artificial neural network (ANN) based model was built to predict the molar absorptivity of those 23 molecules, and the molecule that presented a similar molar absorptivity to that of octinoxate was chosen for synthesis (analog 4, 3-phenylpropyl (E)-3-(4-methoxyphenyl)acrylate). Synthesis for analog 4 resulted in a 90% yield, and its photoprotective properties, lipophilicity and cytotoxicity were then evaluated. Analog 4 absorbed UV radiation in the range of 250-340 nm, and it presented a molar absorptivity of 36,155 M - 1cm-1. Its lipophilicity was evaluated with RP-HPLC resulting in a logkw of 2.49 and its LC50 was greater than octinoxate's (67.41 nM vs. 45.67 nM). Therefore, results showed that ligand based virtual screening is an effective strategy for the development of new organic UV filters, because it guided the design of less toxic analogs and pinpointed the most likely analog to exhibit UV properties similar to those of octinoxate. In this case, analog 4 is a promising alternative to its parent compound since it proved to be more effective and less toxic.

Methyl benzoate and cinnamate analogs as modulators of DNA methylation in hepatocellular carcinoma.

Phenolic acids represent a large collection of phytochemical molecules present in the plant kingdom; they have an important role as epigenetic regulators, particularly as inhibitors of DNA methylation. In the present study, 14 methyl benzoate and cinnamate analogs were synthesized (11-24). Their cytotoxic activity on hepatocellular carcinoma cells (Hep3B) and immortalized human hepatocyte cells was then evaluated. In addition, its effect on the inhibition of global DNA methylation in Hep3B was also determined. Our results showed that the cinnamic derivatives 11-14 and 20-22 were more potent than the free caffeic acid (IC50 109.7-364.2 µM), being methyl 3,4-dihydroxycinammate (12) the most active with an IC50  = 109.7 ± 0.8 µM. Furthermore, 11-14, 20-23 compounds decreased overall DNA methylation levels by 63% to 97%. The analogs methyl 4-hydroxycinnamate (11), methyl 3,4,5-trimethoxycinnamate (14), methyl 4-methoxycinnamate (21), and methyl 3,4-dimethoxycinnamate (22) showed relevant activities of both cytotoxicity and global DNA methylation inhibition. The molecular docking of 21 and 14 suggested that they partly bind to the SAH-binding pocket of DNA methyltransferase 1. These results emphasize the importance of natural products and their analogs as potential sources of DNA methylation modulating agents.

In vitro evidence that the anti-inflammatory effect of synthetic cinnamate-derived dienes is directly linked to a macrophage repolarization.

The inflammatory process is a mammalian physiological reaction against infectious agents or injuries. Among the cells involved, the macrophages have a highlighted role during this process. Depending on the inflammatory context, they can polarize into pro- or anti-inflammatory profiles (M1 and M2). In this context, compounds derived from cinnamic acid have demonstrated strong evidence of anti-inflammatory activity; however, the mechanism responsible for this effect remains unclear. In this study, we investigated the anti-inflammatory activity of five cinnamate-derived dienes of synthetic origin. The compounds that did not demonstrate significant cytotoxicity were tested to assess anti-inflammatory activity (NOx ) in RAW 264.7 cells stimulated with LPS. Then, the selected compound (diene 1) was evaluated as to its ability to inhibit the secretion of pro-inflammatory cytokines (IL-1ß, TNF-α, INF-γ, MCP-1, and IL-6) and increase the production of anti-inflammatory cytokines (IL-13, IL-4, and IL-10). Finally, diene 1 was able to reduce the expression of TLR4 and increase the phagocytic activity of the macrophages. Gathering these results together, we conclude that diene 1 showed an important anti-inflammatory effect, and this effect is linked to its immunomodulatory characteristic. Since the M1 markers were reduced at the same time, M2 markers were increased by the treatment of the macrophages with diene 1.

Synthesis of cinnamic acid ester derivatives with antiproliferative and antimetastatic activities on murine melanoma cells.

Melanoma is the most aggressive skin cancer, and its incidence has continued to rise during the past decades. Conventional treatments present severe side effects in cancer patients, and melanoma can be refractory to commonly used anticancer drugs, which justify the efforts to find new potential anti-melanoma drugs. An alternative to promote the discovery of new pharmacological substances would be modifying chemical groups from a bioactive compound. Here we describe the synthesis of seventeen compounds derived from cinnamic acid and their bioactivity evaluation against melanoma cells. The compound phenyl 2,3-dibromo-3-phenylpropanoate (3q) was the most effective against murine B16-F10 cells, as observed in cytotoxicity and cell migration assays. Simultaneously, this compound showed low cytotoxic activity on non-tumor cells. At the highest concentration, the compound 3q was able to trigger apoptosis, whereas, at lower concentrations, it affected the cell cycle and melanoma cell proliferation. Furthermore, cinnamate 3q impaired cell invasion, adhesion, colonization, and actin polymerization. In conclusion, these results highlight the antiproliferative and antimetastatic potential of cinnamic acid derivatives on melanoma.

A study on the antioxidant activity of rosmarinic acid against carbon tetrachloride-induced liver toxicity in adult male albino rats / Estudio sobre la actividad antioxidante del ácido rosmarínico contra la toxicidad hepática inducida por tetracloruro de carbono en ratas albinas macho adultas

SUMMARY: Carbon tetrachloride (CCl4) is a manufactured chemical and does not occur naturally in the environment. CCl4 is a clear liquid that evaporates very easily. It has a sweet odor. CCl4 is toxic to the mammalian liver and is hepatocarcinogenic in both rats and mice. Rosemary (Rosmarinus Officinalis) is commonly used as a spice and flavoring agent in food processing. It is known for its antioxidant properties. The present study aims to investigate the antioxidant activity of rosmarinic acid (RA) on CCl4-induced liver toxicity in adult male albino rats. Forty adult male albino rats were divided into 4 groups with 10 rats in each group. Group I (control group). Group II animals received RA at a dose of 50 mg/kg/day by oral gavage for 4 weeks. Group III animals received CCl4 intraperitoneally at a dose of 3ml/kg twice weekly for 4 weeks. Group IV animals received CCl4 Plus RA. At the end of the experiment, liver specimens are processed for histological, immunohistochemical, EM and biochemical studies. Administration of RA deceased the elevated serum liver enzymes (AST, ALT, and ALP), elevated MDA level and immunoexpression of the proapoptotic protein (Bax) induced by CCl4. It increased reduced glutathione (GSH), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and immunoexpression of the antiapoptotic protein (Bcl2). It also improved the histological and ultrastructural changes induced by CCl4. It appears that Rosmarinic acid has protective effects against CCl4-induced hepatotoxicity as indicated by biochemical, histological, immunohistochemical and ultrastructural results.

RESUMEN: El tetracloruro de carbono (CCl4) es un producto químico fabricado y no se encuentra de forma natural en el medio ambiente. CCl4 es un líquido transparente que se evapora fácilmente; tiene un olor dulce. CCl4 es tóxico para el hígado de los mamíferos y es hepatocarcinogénico tanto en ratas como en ratones. El romero (Rosmarinus officinalis) se usa comúnmente como condimento y agente aromatizante en el procesamiento de alimentos. Es conocido por sus propiedades antioxidantes. El presente estudio tuvo como objetivo investigar la actividad antioxidante del ácido rosmarínico (RA) sobre la toxicidad hepática inducida por CCl4 en ratas albinas macho adultas. Se dividieron cuarenta ratas albinas macho adultas en 4 grupos con 10 ratas en cada grupo. Grupo I (grupo control). Los animales del grupo II recibieron AR a una dosis de 50 mg / kg / día por sonda oral durante 4 semanas. Los animales del grupo III recibieron CCl4 por vía intraperitoneal a una dosis de 3 ml / kg dos veces por semana durante 4 semanas. Los animales del grupo IV recibieron CCl4 Plus RA. Al final del experimento, las muestras de hígado se procesaron para estudios histológicos, inmunohistoquímicos, EM y bioquímicos. La administración de AR eliminó las enzimas hepáticas séricas elevadas (AST, ALT y ALP), el nivel elevado de MDA y la inmunoexpresión de la proteína proapoptótica (Bax) inducida por CCl4. Aumentó el glutatión reducido (GSH), glutatión peroxidasa (GSH-Px), la superóxido dismutasa (SOD) y la inmunoexpresión de la proteína antiapoptótica (Bcl2). También mejoró los cambios histológicos y ultraestructurales inducidos por CCl4. El ácido rosmarínico puede tener efectos protectores contra la hepatotoxicidad inducida por CCl4, tal como lo indican los resultados bioquímicos, histológicos, inmunohistoquímicos y ultraestructurales.

Curcumin induces peripheral antinociception by opioidergic and cannabinoidergic mechanism: Pharmacological evidence.

BACKGROUND: Curcumin is one of the compounds present in plants of the genus Curcuma sp., being very used not only as condiment but also with medicinal purposes. As an analgesic, papers highlight the efficacy of curcumin in the treatment of various types of pain. AIMS: In this study we evaluated the peripheral antinociceptive effect of curcumin and by which mechanisms this effect is induced. MAIN METHODS: The mice paw pressure test was used on animals which had increased pain sensitivity by intraplantar injection of carrageenan. All the drugs were administered in the right hind paw. KEY FINDINGS: Curcumin was administered to the right hind paw animals induced antinociceptive effect. Non -selective antagonist of opioid receptors naloxone reverted the antinociceptive effect induced by curcumin. Selective antagonists for µ, δ and κ opioid receptors clocinnamox, naltrindole and nor- binaltorphimine, respectively, reverted the antinociceptive effect induced by curcumin. Bestatin, enkephalinases inhibitor that degrade peptides opioids, did not change the nociceptive response. Selective antagonists for CB1 and CB2 cannabinoid receptors, AM251 and AM630, respectively, reversed the antinociceptive effect induced by curcumin. The MAFP inhibitor of the enzyme FAAH which breaks down anandamide, JZL184, enzyme inhibitor MAGL which breaks down the 2-AG, as well as the VDM11 anandamide reuptake inhibitor potentiated the antinociceptive effect of curcumin. SIGNIFICANCE: These results suggest that curcumin possibly peripheral antinociception induced by opioid and cannabinoid systems activation and possibly for endocannabinoids and opioids release.

Antidepressant-like effect of rosmarinic acid during LPS-induced neuroinflammatory model: The potential role of cannabinoid receptors/PPAR-γ signaling pathway.

Rosmarinic acid (RA), an ester of caffeic acid and 3, 4-dihydroxyphenyllactic acid, has anti-inflammatory and neuroprotective activities. Herein, this study investigated in silico the drug-likeness and the potential molecular targets to RA. Moreover, it tested the antidepressant-like potential of RA in the lipopolysaccharide (LPS)-induced depression model. RA (MW = 360.31 g/mol) meets the criteria of both Lipinski's rule of five and the Ghose filter. It also attends to relevant pharmacokinetic parameters. Target prediction analysis identified RA's potential targets and biological activities, including the peroxisome proliferator-activated receptor (PPAR) and the cannabinoid receptors CB1 and CB2 . In vivo, RA's acute, repetitive, and therapeutic administration showed antidepressant-like effect since it significantly reduced the immobility time in the tail suspension test and increased grooming time in the splash test. Further, the pretreatment with antagonists of CB1 , CB2 , and PPAR-γ receptors significantly blocked the antidepressant-like effect of RA. Altogether, our findings suggest that cannabinoid receptors/PPAR-γ signaling pathways are involved with the antidepressant-like effect of RA. Moreover, this molecule meets important physicochemical and pharmacokinetic parameters that favor its bioavailability. RA constitutes a promising, innovative, and safe molecule for the pharmacotherapy of major depressive disorder.

Artepillin C, a major component of Brazilian green propolis, inhibits endoplasmic reticulum stress and protein aggregation.

Propolis, a compound produced by honeybees, has long been used in food and beverages to improve health and prevent diseases. We previously reported that the ethanol extracts of Brazilian green propolis and its constituents artepillin C, kaempferide, and kaempferol mitigate oxidative stress-induced cell death via oxytosis/ferroptosis. Here, we investigated the potential of Brazilian green propolis and its constituents to protect against endoplasmic reticulum stress in the mouse hippocampal cell line HT22. Ethanol extracts of Brazilian green propolis, artepillin C, and kaempferol attenuated tunicamycin-induced unfolded protein response and cell death. Interestingly, artepillin C inhibited both tunicamycin-induced protein aggregation in HT22 cells and the spontaneous protein aggregation of mutant canine superoxide dismutase 1 (E40K-SOD1-EGFP) in Neuro2a cells. These findings indicate that in addition to oxidative stress, the ethanol extracts of Brazilian green propolis help prevent endoplasmic reticulum stress-related neuronal cell death, which is proposedly involved in several neurodegenerative diseases. Moreover, artepillin C, a major constituent of Brazilian green propolis, may exhibit chemical chaperone-like properties.

Synthesis, antitumor activity and in silico analyses of amino acid derivatives of artepillin C, drupanin and baccharin from green propolis.

Breast cancer has the highest incidence and mortality in females, while prostate cancer has the second-highest incidence in males. Studies have shown that compounds from Brazilian green propolis have antitumor activities and can selectively inhibit the AKR1C3 enzyme, overexpressed in hormone-dependent prostate and breast tumors. Thus, in an attempt to develop new cytotoxic inhibitors against these cancers, three prenylated compounds, artepillin C, drupanin and baccharin, were isolated from green propolis to synthesize new derivatives via coupling reactions with different amino acids. All obtained derivatives were submitted to antiproliferative assays against four cancer cells (MCF-7, MDA MB-231, PC-3, and DU145) and two normal cell lines (MCF-10A and PNT-2) to evaluate their cytotoxicity. In general, the best activity was observed for compound6e, derived from drupanin, which exhibited half-maximal inhibitory concentration (IC50) of 9.6 ± 3 µM and selectivity index (SI) of 5.5 against MCF-7 cells.In silicostudies demonstrated that these derivatives present coherent docking interactions and binding modes against AKR1C3, which might represent a possible mechanism of inhibition in MCF-7 cells.

Larvicidal activity and in silico studies of cinnamic acid derivatives against Aedes aegypti (Diptera: Culicidae).

Cinnamic acid derivatives (CAD's) represent a great alternative in the search for insecticides against Aedes aegypti mosquitoes since they have antimicrobial and insecticide properties. Ae. aegypti is responsible for transmitting Dengue, Chikungunya, and Zika viruses, among other arboviruses associated with morbimortality, especially in developing countries. In view of this, in vitro analyses of n-substituted cinnamic acids and esters were performed upon 4th instar larvae (L4) of Ae. aegypti, as well as, molecular docking studies to propose a potential biological target towards this mosquitoes species. The larvicide assays proved that n-substituted ethyl cinnamates showed a more pronounced activity than their corresponding acids, in which p-chlorocinnamate (3j) presented a LC50 value of 8.3 µg/mL. Thusly, external morphologic alterations (rigid and elongated body, curved bowel, and translucent or darkened anal papillae) of mosquitoes' group exposed to compound 3j, were observed by microscopy. In addition, an analytical method was developed for the quantification of the most promising analog by using high-performance liquid chromatography with UV detection (HPLC-UV). Molecular docking studies suggested that the larvicide action is associated with inhibition of acetylcholinesterase (AChE) enzyme. Therefore, expanding the larvicidal study with the cinnamic acid derivatives against the vector Ae. aegypti is important for finding search for more effective larvicides and with lower toxicity, since they have already shown good larvicidal properties against Ae. aegypti.